Journal of Ethnopharmacology 155 (2014) 1450–1466

Contents lists available at ScienceDirect

Journal of Ethnopharmacology journal homepage: www.elsevier.com/locate/jep

Ethnobotanical survey of usage of fresh medicinal plants in Singapore Yin-Yin Siew a, Sogand Zareisedehizadeh a, Wei-Guang Seetoh a, Soek-Ying Neo a, Chay-Hoon Tan b, Hwee-Ling Koh a,n a b

Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore 117543, Singapore Department of Pharmacology, Yong Loo Lin School of Medicine, 10 Medical Drive, Block MD11, #05-09, Singapore 117597, Singapore

art ic l e i nf o

a b s t r a c t

Article history: Received 2 May 2014 Received in revised form 25 June 2014 Accepted 14 July 2014 Available online 22 July 2014

Ethnopharmacological relevance: The use of medicinal plants in human health has been documented since ancient times and they provide a useful source of new therapeutics. In Singapore, despite the accessibility to modern healthcare, there still exist pockets of the population who choose to use locally grown fresh medicinal plants for health promotion and even therapeutic purposes. However to date, there is no published report of first-hand account of their usage in Singapore. As land is scarce and rapidly used for re-development, such important knowledge may be lost if not properly documented in time. This work safeguards the local folk knowledge, and provides information on common and scarcely reported fresh medicinal plants. The objective of this study is to gather information regarding the usage of fresh medicinal plants in Singapore through face-to-face interviews. Materials and Methods: Information on demographic data and plant-use methods were collated via faceto-face interviews of 200 fresh medicinal plant users who have used fresh medicinal plants in the last five years. The survey protocol was approved by the National University of Singapore Institutional Review Board and informed consent was obtained from every participant. Results: A total of 414 plants represented by 104 plant species from 44 families were reportedly used by the 200 participants. The five most commonly used plants were Clinacanthus nutans (34 users), Strobilanthes crispus (31 users), Pereskia bleo (25 users), Aloe vera (18 users) and Zingiber officinale (16 users). Leaves were the most commonly used plant part while preparing a decoction was the most common method of preparation. The majority of interviewees used plants for general health purposes and to treat diseases related to the respiratory system and cancer. Conclusions: Our survey has successfully documented the rich wealth of traditional usage and knowledge on 414 fresh medicinal plants grown in Singapore through face-to-face interviews with 200 users. This study will serve as a useful resource for identifying promising plants for future drug discovery efforts. Scientific evaluations of these medicinal plants are warranted and should be carried out. & 2014 Elsevier Ireland Ltd. All rights reserved.

Keywords: Survey Traditional medicine Cold and influenza Cancer Cardiovascular Traditional Chinese medicine

1. Introduction Medicinal plants have been used for the treatment of diverse ailments for thousands of years (Sofowara, 1982; Hill, 1989). Even with the advent of allopathic medicine, using plants for medicinal purposes is still prevalent in many parts of the world. Singapore, a city-state island country, is situated off the southern tip of the Malay Peninsula. It is highly urbanized and has the third highest per capita income in the world (IMF, 2014). As the country's primary health care system is based on allopathic medicine, traditional herbal medicine is often termed “complementary and alternative medicine (CAM)” (WHO, 2000). Although allopathic medicine is the

n

Corresponding author. Tel.: þ 65 6516 7962. E-mail address: [email protected] (H.-L. Koh).

http://dx.doi.org/10.1016/j.jep.2014.07.024 0378-8741/& 2014 Elsevier Ireland Ltd. All rights reserved.

primary form of healthcare in Singapore, there are patients who choose herbal medicine for health promotion or for treatment of diseases (Koh et al., 2004; Lim et al., 2006; Chan et al., 2012). For example, the local Chinese use Traditional Chinese Medicine (TCM), the Malays use Jamu Medicine and the Indians use Ayurvedic Medicine to complement the allopathic medicine. Most of the herbs are used or consumed in the dried forms imported from countries of origin where the therapeutic systems are established. Alternatively, some of the herbal medicines are sold as finished products. Interestingly, some locals still resort to using fresh medicinal plants. The herbal folk knowledge is handed down verbally from the older generations who used to reside in many kampong villages of Singapore and neighbouring country, Malaysia. Now, all the villages have practically disappeared to make way for rapid urbanisation in land scarce Singapore. Given the fast rate of habitat loss and change, coupled with easy accessibility to modern healthcare, the local herbal

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

usage knowledge may be permanently lost if not properly collated in time. Singapore (11170 N, 1031500 E) has a land area of 715.8 km2 and has a tropical climate characterised by uniform temperature (average annual temperature between 25.0 1C and 31.2 1C), high humidity (average of 80%) and abundant rainfall (2160 mm of rain fall per year) (Singapore Department of Statistics, 2013a). Its total vascular plant flora consists of 4180 species from 1580 genera, 243 families and 6 phyla (Kwek et al., 2009). However, many pharmacological effects of the medicinal plants grown locally are not well-studied. To date, no comprehensive literature is available concerning their usage in Singapore. In addition, there is a dearth of systematic documentation on the usage along with subsequent effects of using fresh medicinal plants grown in this region. It is thus important to preserve valuable herbal knowledge which could be useful for future drug discovery efforts. The objective of this study is to gather information regarding the usage of fresh medicinal plants in Singapore through face-toface interviews.

2. Materials and methods 2.1. Study design The study was conducted between the period of August 2010 and May 2013. Face-to-face interviews were carried out using a standard questionnaire to collect information about people's knowledge and usage of medicinal plants growing in Singapore and the region. Members of the public were recruited via two mainstream local newspapers (The Straits Times and Lian He Zao Bao), or by word of mouth. Various recruitment advertisements were also mounted in the Traditional Chinese Medicine (TCM) clinics and community gardens. Interviews were conducted in English or Mandarin by 3 trained interviewers. Explanations regarding the purpose of the survey were given and informed consent was obtained from every participant prior to the interview. Each interview lasted 1–3 h. A copy of the participant's medical report was requested for wherever possible for a better appraisal and objective reporting of health status. The protocol was approved by the National University of Singapore (NUS) Institutional Review Board. Participants aged 18 and above, who were currently using or had used a fresh medicinal plant grown in Singapore or the region within the past 5 years for health promotion or therapeutic purposes, were interviewed. A sample of the live plant or a photograph of it must be made available for verification purposes. The plant voucher specimens were deposited at the Department of Pharmacy Herbarium at the National University of Singapore. People who used/ consumed only dietary supplements, Chinese proprietary medicine (final dosage forms) and dried herbs obtained from the Chinese medical halls were excluded. Data obtained from the plant-use section comprised of local common names of the plants, plant sources, patterns, reasons and methods of use, dosages, conditions used for, current health status, and other concomitant medications. The data were compiled using the Microsoft Office Excel 2010 programme. 2.2. Identification of plants Plant species were identified according to standard taxonomic methods, literature and plant databases from The Plant List (The Plant List, 2010), The International Plant Names Index (IPNI) (The International Plant Names Index, 2012), National Parks Board (National Parks Board, 2010), Germplasm Resources Information Network's (Germplasm Resources Information Network's (GRIN),

1451

2013), eFloras (eFloras, 2013) and Missouri Botanical Garden (Missouri Botanical Garden, 2013). The nomenclature follows IPNI (The International Plant Names Index, 2012). Both common and scientific plant names were compiled.

3. Results and discussion 3.1. Demographic characteristics A total of 200 users of fresh medicinal plants were interviewed. Of the respondents, 125 (62.5%) were females and 75 (37.5%) were males. The majority were females as they were typically in charge of preparing herbal preparations in the domestic setting. The majority of the respondents were Chinese (190, 95.0%). The Singapore population is slightly over 5 million with highly diverse cultural backgrounds. The majority were Chinese, with Malays and Indians forming significant minorities. In this survey, the median age was 57 years (range: 18–97 years). There was an average of 4 people per household. The median monthly household income from participants in this survey was S$3500. This was considerably lower than the 2011 national consensus (median: S$7040) (Singapore Department of Statistics, 2013b). This suggests that the majority of the plant users interviewed were from a lower income family. Another possible reason was that approximately one-third of the participants were retired, many of whom did not have much income, if any at all. The lower socioeconomic profile may also contribute to the use of herbal medicine as a cheaper and more familiar form of health care. In Singapore, contemporary modern lifestyle and conventional western medicine being the primary healthcare may suggest that herbal medicine is not as widely practiced and accepted as in many other rural communities. However, there were still pockets of the population, especially the elderly, who were using herbal medicine and were interested to share their wealth of information. This study is not intended to be representative of all the fresh medicinal plant users in Singapore. It was conducted over a span of 3 years. Recruitment was conducted by word of mouth and via advertisements at herb gardens. Besides, two mainstream local newspapers were also used as a platform for recruitment. All efforts were made to recruit as many participants as possible. While 200 users is not a big number, it is however not a small number either, considering that the primary form of healthcare in Singapore is allopathic medicine. Moreover, our target subjects are users of fresh medicinal plants and not users of the more commonly used and recognised forms of herbal therapy, e.g. herbal products and dried herbs bought from Chinese medical halls. Therefore, the former constitutes a small group of people in Singapore. The rapid rate of urbanisation coupled with the lack of a concerted effort to record the information put the local herbal wisdom under threat from being lost. Therefore, there is an imperative need for herbal usage documentation and the vast amount of data collected in this study is important to show and to document the use of fresh medicinal plants in a modern society like Singapore. 3.2. Fresh medicinal plants A comprehensive list of all the plants with their scientific and vernacular names, plant parts being used, forms of usage and indications cited by the participants are presented in Table 1. A total of 414 plants represented by 104 plant species from 44 families were reportedly used by the 200 participants. From this study, a great variety of Compositae (10 species) and Lamiaceae (10 species) were reported to be used for their medicinal properties. The third most represented botanical family was Acanthaceae, with

1452

Table 1 Medicinal plant species listed alphabetically and their purpose of use. Species (Family)

Local name(s)

Plant part(s) used

No. of users

Preparation (no. of users)

General health application (no. of users)

Medical application (no. of users)

Acalypha wilkesiana Müll. Arg. (Euphorbiaceae) Acmella uliginosa (Sw.) Cass. (Compositae) Allium ascalonicum L. (Amaryllidaceae)

金边桑 (Jin Bian Sang) 天文草 (Tian Wen Cao) 红葱 (Hong Cong) Shallot Red Onion 红葱 (Hong Cong) Bawang Merah 韭菜 (Jiu Cai) Spring Onion Chinese Chives Aloe vera 芦荟 (Lu Hui) Lidah Buaya

Leaves Flowers Bulbs

1 1 2

– – –

Bulbs (papery skin)

1

Decoction (1) Topical (1) Cooked (1) Decoction (1) Decoction (1)

Hyperlipidemia (1) Toothache (1) Stomach bloatedness (1) Undiagnosed chest pain (1) Vasculitis (1)

Leaves

1

Decoction (1)

Leaves

18

Topical (13) Decoction (10) Eaten raw (1) Juice (1)

General detoxification (1) Prevent seafood allergy (1) 活血 "Invigorate blood circulation" (1) Antibacterial (1) Boost immunity (1) General detoxification (5) Hair care (1) Health promotion (6) Skin care (12) 清热 "Clear heat" (1) 通血 Promote blood circulation (1)

Allium cepa L. (Amaryllidaceae)

Allium tuberosum Rottler ex Spreng. (Amaryllidaceae) Aloe vera (L.) Burm. f. (Asparagaceae)





Alternanthera sessilis (L.) R. Br. ex DC. (Amaranthaceae)

红田乌 (Hong Tian Wu) Red Sessile Joyweed

Whole-plant Leaves and stems

13

Decoction (12) Tea (2)

Ananas comosus (L.) Merr. (Bromeliaceae)

Pineapple 黄梨 (Huang Li) Indian Snake Grass 穿心莲 (Chuan Xin Lian) 苦草 (Ku Cao) Hempedu Bumi Sambiloto

Fruits

1

Juice (1)

Leaves Whole-plant

13

General detoxification (1) 清热 "Clear heat" (1)

Chronic tonsillitis (1) Cold & flu symptoms (1) Diabetes (1) Shingles (1) Sore throat (7)

Peanut 花生 (Hua Sheng) Jering Djenkol Bean 珍珠花菜 (Zhen Zhu Hua Cai) White Mugwort 艾草 (Ai Cao) Mugwort

Seeds

1

Encapsulation (3) Eaten raw (6) Tea (1) Soften in hot hot water, then eaten (1) Macerate in alcohol, then apply alcohol topically (1) Decoction (1)



Cold & flu symptoms (1)

Fruits

1

Eaten raw (1)



Leaves and stems

1

Cooked (1)

清血 "Purify blood" (1)

Diabetes (1) Hypertension (1) –

Whole-plant Leaves and stems Leaves

4

Decoction (2) Cooked (2)

Boost immunity (1) General detoxification (1) Health promotion (2) Skin care (1) 祛风 "Dispel wind" (1)

Andrographis paniculata (Burm. f.) Nees (Acanthaceae)

Arachis hypogaea L. (Leguminosae) Archidendron jiringa (Jack) I. C. Nielsen (Leguminosae) Artemisia lactiflora Wall. ex DC. (Compositae) Artemisia argyi H. Lév. & Vaniot (Compositae)

Boost immunity (1) General detoxification (4) Health promotion (4) Lower cholesterol (1) Prevent hair fall (1) Promote bowel movement (1) Reduce skin hyperpigmentation (1) 清热 "Clear heat" (1) 清血 "Purify blood" (2) 通血 Promote blood circulation (4) –

Uterine cancer (1)

Cold & flu symptoms (1) Irregular menstruation (1)

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Acne (1) Burns (3) Constipation (1) Contact dermatitis (2) Coughs (1) Dry skin (2) Insect bites (1) Itchiness due to rashes (1) Open wound with bleeding (4) Hyperlipidemia (1) Hypertension (2) Nose bleeds (1)

Averrhoa carambola L. (Oxalidaceae)

Azadirachta indica A. Juss. (Meliaceae)

Bergera koenigii L. (Rutaceae) Beta vulgaris L. (Amaranthaceae)

Callicarpa formosana Rolfe (Lamiaceae) Callisia repens (Jacq.) L. (Commelinaceae)

Capsicum annuum L. (Solanaceae) Carica papaya L. (Caricaceae)

Catharanthus roseus (L.) G. Don (Apocynaceae) Centella asiatica (L.) Urb. (Apiaceae)

Cinnamomum cassia (Nees & T. Nees) J. Presl (Lauraceae) Citrus hystrix DC. (Rutaceae) Citrus limon (L.) Burm. f. (Rutaceae) Clinacanthus nutans (Burm. f.) Lindau (Acanthaceae)

Fruits

1

Juice (1)



Lupus nephritis (1)

Leaves Flowers

2

Bath (1) Eaten raw (1) Cooked (1)



Curryleaf 咖哩叶 (Ga Li Ye) Beetroot

Leaves and stems Leaves Roots

2 1

Decoction (1) Tea (1) Juice (1)

Antibacterial (1) Boost immunity (1) Skin care (1) Source of nutrients (1) –

鬼针草 (Gui Zhen Cao) 咸丰草 (Xian Feng Cao) 米碎花 (Mi Sui Hua) 杜虹花 (Du Hong Hua) 水龟草 (Shui Gui Cao) Turtle Vine Inch Plant

Leaves and stems

1

Decoction (1)

Boost immunity (1� Decrease weight (1) Health promotion (1) Lower cholesterol (1) –

Leaves

1

Decoction (1)



Uterine cancer (1)

Leaves and stems Whole-plant Leaves

11

Decoction (11)

Benign growth: Pituitary gland (1) Renal problems (4)

Leaves

1

Cooked (1)

Boost immunity (1) General detoxification (6) Health promotion (3) Prevent urinary tract infection (1) Promote bowel movement (2) 利尿 Diuresis (1) 清血 "Purify blood" (2) –

Dengue (1) Goitre (1) Lichen planus (1) Nasopharyngeal cancer (1) Pre-menstrual symptoms (1) Uterine cancer (1) Diabetes (1)

Bird's Eye Chili 小辣椒 (Xiao La Jiao) Papaya 木瓜 (Mu Gua) Pawpaw

Unripened fruits (skin & seeds) 6 Leaves and stems Leaves

Decoction (1) Juice (4) Decoction, then gargle (1) Tea (1)

Boost immunity (1) General detoxification (1) Health promotion (1)

Madagascar Periwinkle 长春花 (Chang Chun Hua) Gotu Kola Asiatic Pennywort

Roots

1

Decoction (1)



Whole-plant

1

Eaten raw (1) Tea (1)

Cinnamon 肉桂 (Rou Gui) Kayu Manis Hutan Kaffir Lime Limau Purut Lemon 柠檬 (Ning Meng) 忧遁草 (You Dun Cao) Sabah Snake Grass 沙巴蛇草 (Sha Ba She Cao)

Leaves

1

Decoction (1)

Anti-inflammatory (1) Antioxidant (1) Health promotion (1) Lower blood pressure (1) Skin care (1) –

Fruits Leaves Fruits

2

Decoction (1) Eaten raw (1) Juice (1) Tea (1) Decoction (14) Eaten raw (5) Juice (19) Topical (1) Tea (1) Bath (1)

Leaves Leaves and stems Stems

3 34



Hyperlipidemia (2) Hypertension (1) Hyperlipidemia (1)

Benign growth: Thyroid gland (1)

Asthma (1)



Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Bidens pilosa L. (Compositae)

Starfruit 杨桃 (Yang Tao) Belimbing Carambola Neem

Cough (1)

General detoxification (1)

Cold & flu symptoms (1) Mouth ulcers (1) Hypertension (2)

Boost immunity (6) General detoxification (9) Health promotion (9) Prevent cancer (2) Promote bowel movement (1) Skin care (1)

Benign growth: Pituitary gland (1) Benign growth: Thyroid gland (1) Breast cancer (1) Broken capillaries on feet (1) Cold & flu symptoms (2) Goitre (2)

1453

1454

Table 1 (continued ) Species (Family)

Local name(s)

Plant part(s) used

No. of users

Preparation (no. of users)

Medical application (no. of users)

利尿 Diuresis (1) 清血 "Purify blood" (1) 补肾 "Tonify the kidney" (1)

Hypertension (1) Itchiness due to skin rashes (1) Lungs cancer (1) Lymphoma (2) Nasopharyngeal cancer (2) Ovarian cancer (1) Papillary thyroid carcinoma (1) Prostate cancer (1) Renal problems (4) Shingles (1) Stomach cancer (1) Sudden joint weakness in walking (1) Urethral cancer (1) Uterine cancer (1) Uterine fibroid (1) Hyperlipidemia (1)

Cucumis sativus L. (Cucurbitaceae)

Cucumber 黄瓜 (Huang Gua)

Fruits

1

Juice (1)

Curcuma longa L. (Zingiberaceae)

Turmeric 黄姜 (Huang Jiang)

Leaves Roots

3

Cyanthillium cinereum (L.) H. Rob. (Compositae) Cymbopogon citratus (DC.) Stapf (Poaceae)

肖山虎 (Xiao Shan Hu) Lemongrass 香茅 (Xiang Mao)

Leaves Leaves Stems

1 10

Tea (1) Eaten raw (1) Juice (1) Cooked (1) Topical (1) Decoction (9) Tea (1) Gargle (1)

Eleocharis dulcis (Burm. f.) Trin. Ex Hensch. (Cyperaceae)

Chinese Water-chestnut 马蹄 (Ma Ti)

Fruits

1

Eaten raw (1)

Elephantopus scaber L. (Compositae)

地胆草 (Di Dan Cao) Tapak Sulaiman Elephant's Foot 苦粒心 (Ku Li Xin) 三加皮 (San Jia Pi)

Whole-plant

2

Decoction (2)

Leaves and stems

1

Decoction (1)

爬树龙 (Pa Shu Long) Dragon Tail 龙尾草 (Long Wei Cao) Flame-violet 飞扬草 (Fei Yang Cao) Asthma Weed

Leaves Leaves and stems

4

Decoction (4)

General detoxification (1) Liver health (1) Lower blood pressure (1) Lower cholesterol (1) 清热 "Clear heat" (1) 清肝明目 "Clear the liver and improve vision" (1) Cancer prevention (1)

Leaves Leaves Stems Flowers Whole-plant

1 2

Decoction (1) Decoction (1) Topical (1)

– Health promotion (1) 清热 "Clear heat" (1)

Eleutherococcus trifoliatus (L.) S. Y. Hu (Araliaceae)

Epipremnum pinnatum (L.) Engl. (Araceae)

Episcia cupreata (Hook.) Hanst. (Gesneriaceae) Euphorbia hirta L. (Euphorbiaceae)

Boost immunity (1) Decrease weight (1) Health promotion (1) Lower cholesterol (1) 清热 "Clear heat" (1) General detoxification (1) Health promotion (2) Improve energy (1) 清血 "Purify blood" (1) – Aid in digestion (1) General detoxification (3) Health promotion (1) Prevent cancer (1) 清热 "Clear heat" (2) 祛风 "Dispel wind" (2) Health promotion (1) Hypertension prevention (1) Improves energy (1) Promote blood circulation (1) Decrease weight (1) General detoxification (1)

Cold & flu symptoms (1) Colon polyps (1)

Paronychia (1) Cold & flu symptoms (1) Insect bites (1) Sore and itchy throat (1) Stomach bloatedness (2) Swollen gums (1) Uterine cancer (2) –

Cold & flu symptoms (1) Psoriasis (1) Hyperlipidemia (1)

Breast cancer (1) Lungs cancer (1) Uterine cancer (1) Cough (1) Itchiness due to rashes (1) Piles (1)

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

General health application (no. of users)

Ficus deltoidea Jack (Moraceae) Graptophyllum pictum (L.) Griff. (Acanthaceae) Gynostemma pentaphyllum (Thunb.) Makino (Cucurbitaceae) Gynura japonica (Thunb.) Juel (Compositae)

Mas Cotek Mistletoe Fig 紫苋草 (Zi Xian Cao) Caricature-plant 绞股蓝 (Jiao Gu Lan)

Leaves Fruits Leaves

1

Eaten raw (1)

1

Decoction (1)

Leaves and stems Leaves Leaves

2

– Uterine cancer (1)

Health promotion (1)

Benign growth: Pituitary gland (1)

Promote blood flow (1)

Bruises (3) Insect bites (1)

General detoxification (2) Health promotion (4) Uterine cancer (1)

Benign growth: salivary gland (1) Hyperlipidemia (1)



Benign growth: Thyroid gland (1) –

Cold & flu symptoms (1) Lungs cancer (1) Fever (1)

Gynura procumbens (Lour.) Merr. (Compositae)

尖尾凤 (Jian Wei Feng) 救命草 (Jiu Ming Cao)

Leaves

6

Hemigraphis alternate (Burm. f.) T. Anderson (Acanthaceae) Hibiscus sabdariffa L. (Malvaceae)

Red-flame-ivy

Whole-plant

1

Eaten raw (2) Decoction (1) Topical use (3) Cooked (1) Decoction (1) Eaten raw (5) Decoction (2) Soften in hot water, then eaten (1) Decoction (1)

洛神花 (Luo Shen Hua) Roselle

Fruits

2

Decoction (2)

Houttuynia cordata Thunb. (Saururaceae)

鱼腥草 (Yu Xin Cao)

Leaves and stems

4

Decoction (4)

Hydrocotyle sibthorpioides Lam. (Araliaceae)

盆上芫荽 (Pen Shang Yan Sui) Lawn Pennywort Pegaga Embun Sweet-potato Leaves 番薯叶 (Fan Shu Ye) 山莲藕 (Shan Lian Ou) 刺芋 (Ci Yu) 岩陀 (Yan Tuo) Bandicoot-berry Memali 半边莲 (Ban Bian Lian) Singapore-holly 满天星 (Man Tian Xin)

Whole-plant

1

Decoction (1)

Health promotion (1) Improve blood circulation (1) Source of nutrients (1) General detoxification (2) Health promotion (2) 清热 "Clear heat" (1)

Leaves

1

Juice (1)



Bladder cancer (1)

Whole-plant

1

Decoction (1)



Hyperlipidemia (1)

Leaves Leaves and stems

5

Health promotion (2) Prevent cancer (1)

Leaves Whole-plant Leaves and stems

1 5

Eaten raw (3) Decoction (1) Topical (1) Juice (1) Decoction (5)

Benign growth: Salivary gland (1) Benign growth: Thyroid gland (1) Open wound with bleeding (1) Colonic diverticulosis (1) –

Ipomoea batatas (L.) Poir. (Convolvulaceae) Lasia spinosa (L.) Thwaites (Araceae) Leea indica (Burm. f.) Merr. (Vitaceae)

Lobelia chinensis Lour. (Campanulaceae) Malpighia coccigera L. (Malpighiaceae)

菊三七 (Ju San Qi)

3

Melastoma malabathricum L. (Melastomataceae)

白花野牡丹 (Bai Hua Ye Mu Dan) Senduduk Putih

Roots Roots and stems

2

Mentha spicata L. (Lamiaceae)

Spearmint 薄荷 (Bo He)

Leaves

5

Momordica charantia L. (Cucurbitaceae)

Bitter Gourd 苦瓜 (Ku Gua)

Fruits

6

Juice (4) Cooked (2) Decoction (1)

Morinda citrifolia L. (Rubiaceae)

Noni Mengkudu Indian Mulberry

Fruits Leaves Fruit and leaves

4

Moringa oleifera Lam. (Moringaceae)

辣木 (La Mu)

Seeds

4

Juice (3) Cooked (1) Decoction (2) Bath (1) Eaten raw (2)

Decoction (2) Macerate in alcohol, then drunk (1) Tea (2) Decoction (2) Cooked (1) Eaten raw (1)

– General detoxification (3) Kidneys health (1) Liver protection (1) Remove toxins from liver (2) –

Benign growth: Thyroid gland (1) Sexual dysfunction (1)

Cold & flu symptoms (1) Hyperlipidemia (1) Insect bites (1) Laryngitis (1)

General detoxification (1) Health promotion (1) Mood lifting (1) Promote sleep (1) Soothe the stomach (1) 清热 "Clear heat" (2) Boost immunity (1) Decrease weight (1) General detoxification (2) Health promotion (4) Lower cholesterol (1) Skin care (1) 清热 "Clear heat" (2) Anticancer (1) Boost immunity (1)

Constipation (1) Hyperlipidemia (2) Hypertension (2)

Boost immunity (1)

Rheumatoid arthritis (1)

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Health promotion (1) Prevent diabetes (1) –

Cold & flu symptoms (1) Itchiness due to skin rashes (1)

1455

1456

Table 1 (continued ) Species (Family)

Plant part(s) used

Drumsticktree

Leaves Leaves and stems

Morus alba L. (Moraceae)

桑 (Sang) Mulberry

Leaves Stems Leaves and stems

8

Decoction (5) Eaten raw (2) Tea (1)

Murdannia bracteata (C. B. Clarke) J. K. Morton ex D. Y. Hong (Commelinaceae)

北京草 (Bei Jing Cao)

Whole-plant

1

Decoction (1)

Nasturtium officinale R. Br. (Brassicaceae) Ocimum basilicum L. (Lamiaceae)

Watercress 九层塔 (Jiu Ceng Ta) 金不唤 (Jin Bu Huan) Basil

Leaves and stems Leaves

2 4

Ocimum tenuiflorum L. (Lamiaceae)

Holy Basil Leaves Tulsi 白花蛇舌草 (Bai Hua She She Cao) Whole-plant Leaves and stems

2 3

Decoction (2) Cooked (1) Decoction (1) Tea (1) Eaten raw (1) Eaten raw (1) Tea (2) Decoction (3)

2

Decoction (2)

1 8

Topical (1) Decoction (4) Eaten raw (2) Tea (4)

Oldenlandia diffusa (Willd.) Roxb. (Rubiaceae)

No. of users

Preparation (no. of users)

General health application (no. of users)

Medical application (no. of users)

Tea (2) Cooked (1) Decoction (1)

General detoxification (2) Health promotion (2) Improve energy (1) Neutralise acidity in stomach: seeds (1) Prevent cancer (1) Reduce constipation (1) Skin care (1) Anticancer (2) Boost immunity (1) Decrease weight (2) General detoxification (2) Health promotion (1) Lower blood pressure (2) Prevent fever (1) Souce of antioxidant (1) 清肝明目 "Clear the liver and improve vision" (1) 祛湿 "Clear damp" (1) Boost immunity (1) General detoxification (1) Health promotion (1) Prevent colon cancer (1) – Health promotion (2) Promote blood circulation (1) Spurt growth in adolescence (1)

Uterine cancer (1)

Ophiopogon japonicas (Thunb.) Ker Gawl. (Asparagaceae) Opuntia ficus-indica (L.) Mill. (Cactaceae) Orthosiphon aristatus (Blume) Miq. (Lamiaceae)

Mondo-grass 麦冬 (Mai Dong) Prickly-pear 猫须草 (Mao Xu Cao) Cat's-whiskers

Leaves Roots tuber Stems Leaves and stalks Leaves

Paederia foetida L. (Rubiaceae)

鸡矢藤 (Ji Shi Teng) Skunkvine Pandan Leaves 班兰叶 (Ban Lan Ye)

Leaves

2

Leaves

5

Bath (1) Decoction (1) Decoction (5)

Pandanus amaryllifolius Roxb. (Pandanaceae)

Parkia speciosa Hassk. (Leguminosae)

Petai 臭豆 (Chou Dou)

Seeds

3

Eaten raw (3)

Polyscias fruticosa (L.) Harms (Araliaceae)

福禄桐 (Fu Lu Tong)

Leaves and stems

1

Decoction (1)

– –

General detoxification (1) 清热 "Clear heat" (1) Skin care (1) General detoxification (2) Health promotion (3) Lower blood pressure (1) Prevent diabetes (1) 清热 "Clear heat" (1) 清肝明目 "Clear the liver and improve vision" (1) General detoxification (1) General detoxification (1) Health promotion (1) Kidneys health (1) Prevent diabetes (1) Remove toxins from liver (1) General detoxification (1) Health promotion (2) Prevent diabetes (1) Promote bowel movement (1) –

Benign growth: Pituitary gland (1) Insect bites (1)



Cold & flu symptoms (2) Insect bites (1)

Cold & flu symptoms (2) Fever (1) Benign growth: pituitary gland (1) Breast cancer (1) Uterine cancer (1) Cold & flu symptoms (1) Acne (1) Gout (1) Hypertension (1) Renal problems (1)

Itchiness due to skin rashes (1) Insect bites (1) Stomach bloatedness (2)

Diabetes (1) Hypertension (1)

Cough (1)

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Local name(s)

牧草 (Mu Cao) 马草 (Ma Cao)

Leaves and stems Stems

8

Juice (1) Decoction (7)

Peperomia pellucida (L.) Kunth (Piperaceae)

丁草 (Ding Cao) 草胡椒 (Cao Hu Jiao) Seven Star Needle Rose Cactus 七星针 (Qi Xin Zhen)

Whole-plant

1

Decoction (1)

Leaves Flowers Leaves Fruits

25

Leaves

Pereskia bleo (Kunth) DC. (Cactaceae)

Pereskia grandifolia Haw. (Cactaceae) Perilla frutescens (L.) Britton (Lamiaceae)

七星针 (Qi Xin Zhen) Rose Cactus 紫苏 (Zi Su) Perilla

Boost immunity (2) General detoxification (2) Health promotion (3) Lower blood pressure (2) 清热 "Clear heat" (2) –

Benign growth: pituitary gland (1) Renal problems (1) Stomach bloatedness (1) Uterine cancer (1)

Eaten raw (16) Decoction (5) Topical (2) Juice (1) Cooked (2)

Boost immunity (1) Cartilage formation (1) Detoxify nicotine (1) General detoxification (5) Health promotion (8) Prevent cancer (5) Prevent cancer relapse (2) Prevent gastritis (1) Promote bowel movement (6) Replenish enzymes (1) 活血化瘀 "Activate blood and dissolve stasis" (2)

1

Eaten raw (1)



Benign growth: Salivary gland (2) Benign growth: Thyroid gland (1) Benign growth: Upper palate (1) Breast cancer (2) Cold & flu symptoms (1) Cold sores (1) Constipation (3) Diabetes (1) Leukemia (1) Lungs cancer (1) Lymphoma (1) Osteoarthritis (1) Prostate cancer (1) Renal problems (1) Uterine cancer (1) Benign growth: Thyroid gland (1)

Leaves

1

Joint pain (1)



Peristrophe roxburghiana (Schult.) Bremek. (Acanthaceae)

红丝线 (Hong Si Xian)

Whole-plant

2

Persicaria chinensis (L.) H. Gross (Polygonaceae)

穷人燕窝 (Qiong Ren Yan Wo) 火炭母 (Huo Tan Mu)

Leaves

5

Phyla nodiflora (L.) Greene (Verbenaceae)

过江藤 (Guo Jiang Teng)

Leaves and stems

2

Decoction (1) Clear the colon (1) Garnish on fish (1) General detoxification (1) Health promotion (1) Remove toxins from seafood (1) 祛风 "Dispel wind" (1) Decoction (2) General detoxification (1) Health promotion (2) 清热 "Clear heat" (1) Decoction (2) Boost immunity (2) Eaten raw (2) General detoxification (1) Health promotion (1) Skin care (2) 补肺 "Tonify the lung" (3) Decoction (2) –

Phyllanthus urinaria L. (Phyllanthaceae)

叶下珠 (Ye Xia Zhu) Underleaf Pearl Betel Leaves Daun Sirih Pepper 胡椒 (Hu Jiao) 车前草 (Che Qian Cao) Common Plaintain Daun Sejumbok

Whole-plant

1

Decoction (1)



Benign growth: Thyroid gland (1) Uterine cancer (1) Liver cirrhosis (1)

Leaves

1

Topical use (1)



Acne (1)

Seeds

1

Decoction (1)



Toothache (1)

Whole-plant

3

Decoction (3)

General detoxification (2) Health promotion (1) 利尿 Diuresis (1) 清热 "Clear heat" (2) General good lung function (1) Health promotion (2) Reduces phlegm (1) Source of nutrients (1) General detoxification (1) Liver health (1) Lower blood pressure (1) Lower cholesterol (1) 清热 "Clear heat" (1) 清肝明目 "Clear the liver and improve vision" (1) General detoxification (2)

Difficulty in urination (1) Lupus nephritis (1) Stinging sensation in urination (1)

Piper betle L. (Piperaceae) Piper nigrum L. (Piperaceae) Plantago major L. (Plantaginaceae)

Indian-borage 印度薄荷 (Yin Du Bo He)

Leaves Whole-plant

13

Pluchea indica (L.) Less. (Compositae)

栾樨 (Luan Xi)

Leaves and stems

1

Decoction (9) Cooked (1) Tea (4) Eaten raw (1) Decoction (1)

Prunella vulgaris L. (Lamiaceae)

夏枯草 (Xia Ku Cao)

Leaves and stem

6

Decoction (6)

Cold & flu symptoms (12)

Hyperlipidemia (1)

Benign growth: Pituitary gland (1)

1457

Plectranthus amboinicus (Lour.) Spreng. (Lamiaceae)

Cold & flu symptoms (1) Difficulty in urination (1) Stinging sensation in urination (1) –

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Pennisetum purpureum Schumach. (Poaceae)

1458

Table 1 (continued ) Species (Family)

Local name(s)

Plant part(s) used

No. of users

Preparation (no. of users)

Selfheal

白鹤灵芝 (Bai He Ling Zhi)

Leaves

2

Decoction (2) Bath (1)

Rorippa indica (L.) Hiern (Brassicaceae)

野葛菜 (Ye Ge Cai) 蔊菜 (Han Cai)

Whole-plant

1

Decoction (1)

Ruta graveolens L. (Rutaceae)

臭草 (Chou Cao) Common Rue 龙脷叶 (Long Li Ye)

Whole-plant

1

Decoction (1)

Leaves

2

Decoction (2)

半枝莲 (Ban Zhi Lian) 黄花母 (Huang Hua Mu) Cherry Tomato 小番茄 (Xiao Fan Qie) 玉龙鞭 (Yu Long Bian)

Whole-plant Leaves and stems Fruits

1 1 1

Decoction (1) Decoction (1) Eaten raw (1)

Whole-plant Leaves

3

Decoction (2) Eaten raw (1)

Strobilanthes crispus (L.) Blume (Acanthaceae)

黑面将军 (Hei Mian Jiang Jun) Black Face General

Leaves and stems Leaves

31

Decoction (23) Juice (5) Dried & encapsulation (1) Tea (3) Eaten raw (1)

Swietenia macrophylla King (Meliaceae)

指天果 (Zhi Tian Guo) Mahogany 向天果 (Xiang Tian Guo)

Seeds

4

Eaten raw (4)

Sauropus spatulifolius Beille (Phyllanthaceae)

Scutellaria barbata D. Don (Lamiaceae) Sida rhombifolia L. (Malvaceae) Solanum lycopersicum Lam. (Solanaceae) Stachytarpheta jamaicensis (L.) Vahl (Verbenaceae)

Medical application (no. of users)

Health promotion (1)

Benign growth: Salivary gland (1) Benign growth: Thyroid gland (1) Fever (1) Hypertension (1) Stroke (1) Psoriasis (1)

Decrease weight (1) General detoxification (2) Health promotion (1) Boost immunity (1) General detoxification (1) Health promotion (1) 清热 "Clear heat" (1) General detoxification (1) Boost immunity (1) General detoxification (1) Health promotion (2) Improves blood circulation (1) 清热 "Clear heat" (1) 祛寒 "Dispel cold" (1) – – Eye health (1) Skin care (1) General detoxification (2) Health promotion (1) Liver health (1) Lower blood pressure (1) Lower cholesterol (1) 清热 "Clear heat" (2) 清肝明目 "Clear the liver and improve vision" (1) Boost immunity (2) General detoxification (9) Health promotion (9) Lower blood pressure (2) Prevent cancer (3) Prevent cold and flu (1) Prevent gall stones (1) Promote bowel movement (1) Skin care (1) 清热 "Clear heat" (2)

Health promotion (1) Mental alertness (1) Reduce blood sugar (1) Reduce cholesterol (1)



– Coughs (2)

Benign growth: Pituitary gland (1) Benign growth: Thyroid gland (1) – Hyperlipidemia (1) Toothache (1)

Benign growth: Neck (1) Benign growth: Pituitary gland (1) Benign growth: Salivary gland (1) Benign growth: Thyroid gland (1) Contact dermatitis (1) Diabetes (1) Goitre (1) Hyperlipidemia (1) Lungs cancer (1) Lymphoma (2) Nasopharyngeal cancer (2) Skin allergies (1) Sore and itchy throat (1) Stomach bloatedness (1) Urethral cancer (1) Uterine cancer (2) Coronary heart disease (1) Diabetes (1) Hyperlipidemia (1) Hypertension (3)

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Rhinacanthus nasutus (L.) Kurz (Acanthaceae)

General health application (no. of users)

Tinospora crispa (L.) Hook. f. & Thomson (Menispermaceae)

过江龙 (Guo Jiang Long) 苦藤 (Ku Teng) Akar Patawali Akar Seruntum

Tradescantia pallida (Rose) D. R. Hunt (Commelinaceae) Purpleheart Trandescantia spathacea Sw. (Commelinaceae) 红竹叶 (Hong Zhu Ye) 蚌兰 (Bang Lan) Moses-in-the-cradle Oyster Plant Triticum aestivum L. (Poaceae) Wheatgrass 小麦草 (Xiao Mai Cao)

Vernonia amygdalina Delile (Compositae)

Vigna radiate (L.) R. Wilczek (Leguminosae)

Vitex trifolia L. (Lamiaceae)

Zingiber officinale Roscoe (Zingiberaceae)

地桃花 (Di Tao Hua) Pepulut 南非叶 (Nan Fei Ye) African Leaves Bitterleaf

Mung-bean Green beans 绿豆 (Lu Dou) 三叶蔓荆 (San Ye Man Jing) Simpleleaf Chastetree Ginger 姜 (Jiang) Halia

2

Decoction (2)

Leaves Leaves

1 2

Tea (1) Decoction (2)

Leaves

1

Juice (1)

Leaves

1

Eaten raw (1)

Leaves Leaves and stems

13

Eaten raw (9) Decoction (3) Juice (1)

Seeds

1

Decoction (1)

Leaves

2

Decoction (1) Tea (2)

Boost immunity (2) General detoxification (6) Health promotion (6) Lower blood pressure (1) Prevent cancer (2) Prevent hypertension (1) Remove bad breath (1) 清热 "Clear heat" (1) 清血 "Purify blood" (1) 降肝火 "Reduce liver fire" (1) General detoxification (1) Health promotion (1) 清热 "Clear heat" (1) Health promotion (1) 清热 "Clear heat" (1)

Rhizomes

16

Cooked (5) Eaten raw (2) Tea (1) Topical (2) Decoction (10) Juice (1)

Cancer prevention (1) Boost immunity (1) Health promotion (5) Promote digestion (1) 祛寒 "Dispel cold" (1) 祛风 "Dispel wind" (4)

Sexual dysfunction (2) –

– –

Fatty liver (1)

Benign growth: Salivary gland (1) Benign growth: Salivary gland (1) Cold & flu symptoms (1) Diabetes (2) Hypertension (1) Insomnia (1) Uterine cancer (2)

Food poisoning (1)

Diabetes (1)

Bruises (1) Cold & flu symptoms (3) Fever (1) Fibromyalgia (1) Gastroenteritis (1) Hair loss (1) Hyperlipidemia (1) Menopause symptom: Chills (1) Menstrual cramps (2) Smoking cessation (1)

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Urena lobata L. (Malvaceae)

Skin care (1) Boost immunity (1) Diabetes prevention (1) General detoxification (1) Health promotion (2) Skin care (1) Health promotion (1) Boost immunity (1) General detoxification (1) Health promotion (1) 清热 "Clear heat" (2) Decrease weight (1) General detoxification (1) Promote bowel movement (1) –

Leaves Vines

1459

1460

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

7 species reported. The main sources of these plants were own residences (127 plants), local markets (124 plants), community gardens (131 plants), other people's residences (28 plants), roadside (13 plants), local farms (6 plants), community parks (4 plants), and forests (2 plants). Plants were also harvested from community gardens maintained by volunteers growing a variety of vegetables and herbs. The community gardens served as a fertile ground for the exchange of information about plant usage. A total of 154 (37.2%) of 414 plants were used for general health, 195 (47.1%) for treatment of medical conditions and 65 (15.7%) for both purposes depending on the user's situation of use. The top five commonly used plants were Clinacanthus nutans, Strobilanthes crispus, Pereskia bleo, Aloe vera and Zingiber officinale. The following is a short review of these five plants. 3.2.1. Clinacanthus nutans (Sabah Snake Grass) Clinacanthus nutans had the highest number of users (34 users, 17.0%) in this study. Twelve cancer patients reported using the plant for treatment or to prevent relapse. In our study, many participants shared that word of mouth sharing by friends, e-mail circulation and blog entries of success stories by cancer survivors have led them to take the plants. Traditionally, the leaves are used in herpes simplex virus treatment in Thailand (Vachirayonstien et al., 2010). They are also used in folk medicine for their antidiabetic, blood pressure lowering, antilytic and diuretic properties (Wanikiat et al., 2008; Yong et al., 2013). In Malaysia and Singapore, the leaves are frequently juiced to treat or prevent cancer. So far, there is a dearth of information with regards to its efficacy as an anticancer herb. The advent of the internet has facilitated free sharing of information with far-reaching impact, which on the one hand is educational, but on the other hand, could be detrimental to health if followed indiscriminately or if information is erroneous. Clinacanthus nutans could be effective against certain, albeit not all, cancer cell lines. A study has demonstrated that the chloroform extract has exerted the highest antiproliferative effect on human erythroleukemia K-562 cell line (IC50 value¼47.70 μg/ml) and human Burkitt's lymphoma Raji cell line (IC50 value¼47.31 μg/ml), but not on human neuroblastoma IMR-32 cell line (Yong et al., 2013). The plant could have exerted its anticancer effect via other mechanism of actions and further studies are warranted in these regards. Besides anticancer activity, other studies conducted thus far were related to its anti-herpes simplex (Janwitayanuchit et al., 2003; Sakdarat et al., 2009; Vachirayonstien et al., 2010; Kongkaew and Chaiyakunapruk, 2011; Kunsorn et al., 2013), anti-inflammatory (Wanikiat et al., 2008) and antioxidant (Yong et al., 2013) activities. 3.2.2. Strobilanthes crispus (Black Face General) In our study, 31 participants used Strobilanthes crispus. Eight of them took the plant for the treatment of cancer. The most common method of preparation was to boil the leaves and stems, and then the resulting decoction was consumed. The leaves of Strobilanthes crispus are used in folk medicine for their anticancer, antidiabetic, blood pressure lowering, antilytic and diuretic properties (Yaacob et al., 2010; Chong et al., 2012). Commercially, the leaves are available as herbal tea product (Fadzelly et al., 2006). Both fermented and unfermented teas were reported to improve lipid profiles, and this may in part be due to the antioxidant and polyphenol contents that were present in the extracts (Fadzelly et al., 2006). In addition, the catechins isolated demonstrated higher antioxidant activity than vitamin E (Ismail et al., 2000). The scientific studies conducted thus far include anticancer (Yaacob et al., 2010), antidiabetic (Fadzelly et al., 2006), antioxidant (Ismail et al., 2000; Iqbal et al., 2010) and cytotoxicity (Chong

et al., 2012) studies. It has been shown that the leaf extract killed breast and prostate cancer cells, but was non-cytotoxic to the normal breast epithelial cells (Yaacob et al., 2010). In vitro study on hormone dependent breast cancer cell line MCF-7 suggested that the plant extract could induce apoptosis and DNA fragmentation via mitochondria dependent p53 apoptosis pathway (Chong et al., 2012). 3.2.3. Pereskia bleo (Seven Star Needle) A total of 25 participants used Pereskia bleo, of which 16 of them ate and chewed the fresh fleshy leaves. The most commonly mentioned indications for leaves consumption were for cancer prevention (5 users, 25.0%), relapse prevention (2 users, 1.0%), treatment of benign growths (4 users, 2.0%) and cancer (7 users, 35.0%). The leaves of Pereskia bleo are commonly boiled or consumed raw to treat diabetes, hypertension, rheumatism, cancer-related diseases, inflammation, gastric pain, ulcers and for revitalizing the body by local communities in Malaysia (Abdul-Wahab et al., 2012, Zareisedehizadeh et al., 2014). In a survey of 9 users of Pereskia bleo in Malaysia, it was reported that the plant was used to treat cancer, muscular ache, hypertension, gestational diabetes, cyst, boils or as health supplement (Khor et al., 2013). Pereskia bleo has been studied for its antinociceptive (AbdulWahab et al., 2012), antiproliferative (Er et al., 2007), apoptotic (Tan et al., 2005), cytotoxicity (Malek et al., 2009) and mutagenic (Er et al., 2007) activities. In concordance with the traditional use of Pereskia bleo in the treatment of cancer, the extracts were shown experimentally in vitro to present anticancer properties. In this survey, two breast cancer patients shared that they consumed the leaves to prevent relapse of the cancer. Previous studies showed that the crude methanol leaf extract demonstrated anticancer activity against human hormone-dependent breast cancer cell lines, with an IC50 value of 39.0 μg/mL in MCF7 cells and EC50 value of 2.0 μg /mL in T47-D cells (Tan et al., 2005; Malek et al., 2009). The compound, di-tert-butylphenol, isolated from leaves had the strongest cytotoxic activity against nasopharyngeal epidermoid carcinoma (KB) cells (IC50 value ¼0.81 μg/mL), amongst other human carcinoma cell lines (KB, CasKi, HCT 116, MCF7, and A549) tested (Malek et al., 2009). 3.2.4. Aloe vera In the survey, 18 participants (9.0%) used Aloe vera. The fleshy leaves of Aloe vera were generally indicated for health promotion, general detoxification, skin care and healing of wounds or skinrelated conditions. It was commonly used given its flexibility in usage, either orally or topically. Good reviews of Aloe vera have been published (Richardson et al., 2005; Surjushe et al., 2008). Aloe vera is traditionally used for the treatment of pimples, acne and mouth ulcers. It has also been used to control bleeding, itching of piles and relief from arthritic pain. The Chinese use the plant juice as a mild laxative, wash for piles, abscesses and scabies. In the Philippines, it is used to treat dysentery and pain in the kidneys (Koh et al., 2010). Due to the prevalence of its use, many studies have been conducted to assess its efficacy in treatment. Some examples of the studies include angiogenic (Lee et al., 1998; Moon et al., 1999; Choi et al., 2002), anti-angiogenic (Cárdenas et al., 2006; Suboj et al., 2012a), antiinflammatory (Yagi et al., 2002; Park et al., 2009), antileishmanial (Dutta et al., 2008), antioxidant (Hu et al., 2003; Anilakumar et al., 2010), antiproliferative (Kuo et al., 2002; Woo et al., 2002; Nićiforović et al., 2007; El-Shemy et al., 2010; Saini et al., 2010; Tabolacci et al., 2010, 2011; Popadic et al., 2012; Suboj et al., 2012b; Tabolacci et al., 2013), chemopreventive (Chaudhary et al., 2007), immunomodulatory (Zhang et al., 2006; Rishi et al., 2008), radioprotective (Goyal and

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Gehlot, 2009) and wound healing (Feily and Namazi, 2009; Takzare et al., 2009; Hosseinimehr et al., 2010; Atiba et al., 2011; Dat et al., 2012; Inpanya et al., 2012). 3.2.5. Zingiber officinale (ginger) Zingiber officinale was used by 16 participants (8.0%) in this study. Ginger was used to treat a myriad of conditions, for example, cold and flu, fibromyalgia, menstrual cramps, gastric problem and bruises (Table 1). Four users reported that ginger dispels “wind” and “cold” in accordance to TCM theory. Ginger has a long history of use as herbal medicine to treat a variety of ailments including vomiting, pain, indigestion, and coldinduced syndromes (Wang and Wang, 2005; White, 2007). The medicinal importance of ginger is widely acknowledged in many traditional herbal systems, including TCM, whereby dried ginger (ganjiang) warms the spleen and stomach, dissipates cold, restores yang, unblocks the channels, warms the lung, and transforms fluids (Zhao and Xiao, 2009); raw ginger (shengjiang) dispels windcold, warms the spleen and stomach, stops vomiting, warms the lung and stops coughing (Zhao and Xiao, 2009). Reviews on specific aspects of the actions of ginger, for example, anti-inflammatory (Grzanna et al., 2005), cancer prevention (Shukla and Singh, 2007) and antiemetic (Ernst and Pittler, 2000; Bryer, 2005; Chaiyakunapruk et al., 2006), have been published. 3.2.6. Other plant species Culturally, the different ethnic groups may use specific plants. For example, the Malays take Parkia speciosa (Petai) and Archidendron jiringa (Jering) raw as ulam (traditional Malay salad) for their supposed health benefits. Plectranthus amboinicus (Indian Borage), Azadirachta indica (Neem) and Ocimum tenuiflorum (Holy Basil) are traditionally used by the Indians. Plants constitute an important aspect of natural treatment in human history, and this could partly explain the divergent species used. Their prevalence of use as reported in our study, coupled with the introduction of in vitro assays to determine whether plants could exert a biological activity, will pave the path for the discovery of bioactive molecules from plants. From our survey, we noted that most of the plants were simply identified by their common names. Many species that look alike can be misidentified, especially for wild plants. Paederia foetida (Skunk Vine) was incorrectly identified by a participant in this study who intended it for contact dermatitis. Although the plant that was used by mistake did not improve her contact dermatitis condition, it did not cause any adverse reaction either. Paederia foetida is known for the strong, sulphurous odour exuded when its

1461

leaves are crushed. This is because the oil responsible for the smell contains sulphur compounds, mainly dimethyl sulphide (Wong and Tan, 1994). The plant Oldenlandia corymbosa (水线草 Shui Xian Cao) was mistakenly identified as Oldenlandia diffusa (白花蛇舌草 Bai Hua She She Cao), the intended plant, and consumed by a user for cancer prevention. The user was subsequently notified of the mistake. In addition, the use of a common name for different species may cause confusion and result in wrong usage. For example, the common name “Seven Star Needles” (七星针 Qi Xin Zhen) was being used interchangeably in reference to Pereskia bleo and Pereskia grandifolia. These two plant species appear vegetatively similar but they can be distinguished by botanical differences in their flowers, leaves and spines. Pereskia bleo has thinner, corrugated leaves and orangy-red flowers, with shorter spines compared to Pereskia grandifolia. In contrast, Pereskia grandifolia has thicker, uncorrugated leaves and purplish-pink flowers, with longer and fewer spines (Sim et al., 2010). Both plants exhibited no evidence of adverse effects or mortalities observed in mice after acute oral administration at the highest dose of 2500 mg/ kg crude extracts (Sim et al., 2010). 3.3. Pattern of plant use In this survey, the participants were asked whether the plants were used for general health purposes or for specific medical conditions. Participants could give more than one reason of use, where applicable. Fig. 1 shows the pattern of plant use for general health purposes. The top 3 general health categories for which plants were used were health promotion, detoxification and boost immunity. Many users have particularly expressed the desire to further improve their health status so as to continue enjoying good health as they age. Interestingly, there were 9 users who perceived that some of the mildly intolerable gastrointestinal and urinary manifestations, such as diarrhoea and increased urination, were positive signs of detoxification. Besides general health, plants were also used for the treatment of medical conditions. Table 2 summarises the medical conditions for which fresh medicinal plants were used, according to the International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) disease categories (WHO, 2014). The majority of participants used plants to treat disease related to the respiratory system. Medicinal plants were often used to treat simple ailments such as cold and flu that were mostly self-limiting and did not warrant the need to seek medical help. Surprisingly, fresh medicinal plants were applied not only in minor ailments, but also in major conditions such as neoplasm. In our survey, medicinal

Fig. 1. Pattern of fresh medicinal plant use for general health purposes.

1462

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Table 2 Medical conditions for which fresh medicinal plants were used and the respective no. of users and species. No.

Disease category

Disease

No. of plant species

No. of users

Total no. of users

1

Diseases of respiratory system

Neoplasm

3

Diseases of circulatory system

4

Diseases of digestive systems

5

Endocrine, nutritional and metabolic disorders

6

Diseases of skin and subcutaneous tissue

7

Injury, poisoning and consequences of external causes

8

Diseases of genitourinary system

9

Diseases of musculoskeletal system and connective tissue

1 26 3 1 1 1 1 1 1 1 9 9 14 1 1 4 1 5 3 4 1 2 1 1 2 14 1 1 1 11 2 1 3 1 2 8 2 1 3 9 3 14 4 7 1 1 1 2 3 2 1 7 2 2 1 2 1 7 2 4 1 2 2 1 1 2 1 2 1 1 1

1 42 3 1 1 1 1 1 1 1 1 1 1 1 1 4 1 4 2 3 1 2 1 1 1 1 1 1 1 14 2 1 5 1 2 7 2 1 1 7 2 10 4 5 1 1 1 1 3 4 3 3 5 2 2 3 1 6 1 4 1 1 2 1 1 3 1 2 1 1 1

50

2

Asthma (chronic) Cold and flu symptoms Cough (dry or wet) Laryngitis Nose blockage Tonsillitis (chronic) Tonsillitis (post radiotherapy) Benign Breast nodule Multiple colonic polyposis Palate Pituitary macroadenoma Salivary gland cyst Thyroid cyst Uterine fibroid Malignant Bladder Breast Leukaemia Lungs Lymphoma Nasopharynx Ovary Prostate Stomach Thyroid Urethra Uterus Angina Cerebrovascular stroke Haemorrhoid Hypertension Thrombosis Vasculitis Constipation Diverticulitis Fatty liver and cirrhosis Gastritis and gastric distension Mouth ulcer and gingivitis Reflux Toothache Diabetes mellitus Goitre Hyperlipidaemia Acne Allergic dermatitis Hair loss Lichen planus Paronychia Psoriasis Rash and itchiness due to different reasons Bruise Burn (hot water) Insect bite Wound Abnormal uterine bleeding Dysmenorrhoea Male erectile dysfunction Premenstrual symptoms Renal problems (haematuria and renal failure) Urinary tract infection Arthritis, Chondrocalcinosis, Gout Joint weakness Lupus nephritis Myalgia Dengue Gastroenteritis Herpes zoster Cold sores Insomnia Depression Diabetic retinopathy Restlessness and agitation

10

Infectious and parasitic diseases

11 12 13 14

Diseases of nervous system Mental behavioural diseases Diseases of eye and adnexa Clinical and preclinical finding without specific diagnosis

29

20

19

17

16

15

15

8

6

2 1 1 1

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

plants were taken by cancer patients in their belief that the plants can control cancer, keep cancer in remission or alleviate the side effects of chemotherapy and radiotherapy. In particular, 14 of the cancer patients in the study were suffering from either advanced or metastatic cancers. The fear of adverse effects from radio- and chemotherapy, a belief that medicinal plants can potentiate the clinical effects of chemotherapeutic drugs and success stories from other plant users were three commonly cited reasons which have prompted them to use herbal medicine in cancer. Fresh medicinal plants were also used in chronic conditions, for example hypertension (14 users), hyperlipidaemia (10 users) and diabetes mellitus (7 users). This is in agreement with a published report that most of the total disease burden in Singapore was attributed to chronic conditions, with the leading contributors being hypertension (23.5%), high total cholesterol (17.4%) and diabetes (11.3%) (Ministry of Health Singapore, 2012). A study in Singapore on patients with chronic conditions found that the use of CAM is strongly determined by the “chronic disease triad” (arthritis, musculoskeletal disorder and stroke), strong adherence to cultural health beliefs and perceived satisfaction with care (Lee et al., 2004). Some patients may experience dissatisfaction related to the inability of conventional medicine to adequately treat and control symptoms such as debilitating pain (Astin, 1998). As a result, many plant species were used complementarily with western medicine in the control of chronic conditions. The plant-use information section consisted of open-ended questions, which allowed room for a greater breadth of answers. In particular, we have documented the traditional healing practices by collecting data on preparatory procedures and administration of herbal remedies. The information shared by all the study participants may be analysed as a whole, yet at the same time every individual recounted real life plant usage situations that could be considered as a standalone case study. This is unlike most

Table 3 Patterns of fresh medicinal plant use for conditions based on TCM diagnosis. Condition based on TCM diagnosis

No. of users

No. of plant species

Heat syndrome Wind syndrome Blood syndrome Dampness Phlegm Cold syndrome Qi deficiency Others (supplement lung and kidney, increase urine flow)

36 9 6 3 3 2 1 9

31 5 6 3 3 1 1 7

1463

other ethnobotanical surveys where selected informants were surveyed about their knowledge of herbs in general. In this study, plants were also used for conditions based on TCM diagnosis (Wiseman, 1995; Men and Guo, 2010), as shown in Table 3. These conditions were most of the time self-diagnosed, with the aim to supplement the body by restoring the balance of yin and yang (which should be balanced for a healthy life), removing “heat” and “wind” etc. Some users opined that fresh herbs were used instead of dried herbs as the former were in nature more “cooling”, and thus capable of clearing excessive “heat” from the body. 3.4. Method of preparation and use The most commonly used botanical part was the leaves (212 plants), followed by the stems with leaves (83 plants), whole plants (44 plants), stems (30 plants), fruits (25 plants), seeds (11 plants) and roots (5 plants). The specific part used in each species is detailed in Table 1. Traditionally, specific botanical parts were sometimes utilised to treat ailments. Variations in types and concentrations of phytoconstituents derived from botanical parts in a species may result in distinct pharmacological activities. The method of administration can be broadly divided into two categories: oral ingestion and topical application, as shown in Table 4. Preparing a decoction was the most common preparative method, and it involved boiling the plant parts in water. The duration required for preparing a decoction varied from half an hour to as long as 20 h. The use of clay pots was preferred over metallic pots to minimise leaching of metallic elements which may catalyse undesirable reactions affecting the efficacy of the herbs (Rubin and Gold, 2002). Stems from Pennisetum purpureum (马草 Ma Cao), Strobilanthes crispus (Black Face General) and Malpighia coccigera (满天星 Man Tian Xing) required boiling for a longer period of time (up to 3 h) to soften the plant materials. Infusions were appropriate for delicate plants such as Orthosiphon aristatus (Cat's-whiskers) and Mentha spicata (Spearmint). Encapsulation of the dried plant materials in gelatin capsules was sometimes employed to mask the bitterness of the plants, as in the case of Andrographis paniculata (穿心莲 Chuan Xin Lian). The softer leaves of Plectranthus amboinicus (Indian Borage), Clinacanthus nutans (Sabah Snake Grass), Vernonia amygdalina (African Leaves), Andrographis paniculata (Indian Snake Grass), Gynura procumbens (尖尾凤 Jian Wei Feng) and Pereskia bleo (Seven Star Needle) were commonly taken fresh. Users cited reasons such as convenience and avoidance of potential degradation of heat-sensitive compounds. Interestingly, users also mentioned the need to ingest an odd number of leaves, i.e. 1, 3, 5 or 7, although the rationale behind this

Table 4 Methods and number of preparations. Type of preparation Oral

No. of preparations Heating involved

No heating involved

Topical

Heating involved No heating involved

Boiled plants, then drank liquid Tea (infused leaves in boiling water, then drank liquid) Cooked (stir fry) plants, then eaten Sun dried and crushed plants, followed by encapsulation Blanched plants, then eaten Boiled plants, then gargle liquid Chewed/swallowed plants raw Juice/blending plants raw Macerate plants in alcohol, then drunk liquid Boiled plants, then bathed in liquid Direct application of plants on skin Bath Macerate plants in alcohol, then apply liquid topically

229 39 20 4 2 2 86 50 1 4 29 1 1

1464

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Table 5 Reported outcomes of plant usage. Reported outcomes

No. of participants

No. of plants

Condition improved/Symptomatic relief Well-being Complete cure No effect Condition under control Condition worsened Unsure about effect

118 98 31 13 11 5 4

185 193 45 13 14 5 4

was unknown. This practice was especially prevalent when taking the raw leaves of Andrographis paniculata and Pereskia bleo. The methods of preparation were often suited for the purpose of use. The bland-tasting leaves of Pereskia bleo when chewed would exude sticky sap capable of absorbing water to become a gelatinous, viscous substance, which may explain its use in promoting bowel movement by 6 users. In the treatment of sore throat, leaves of Andrographis paniculata were deliberately chewed to allow the sap to trickle down and exert its effect on the throat. The chewed material is very bitter, hence its Chinese name “Ku Cao”, which literally means “bitter grass”. The treatment of skinrelated conditions would entail topical application of preparations. Bathing in boiled concoction of plants such as Paederia foetida (Skunk vine) and Rhinacanthus nasutus (白鹤灵芝 Bai He Ling Zhi) was traditionally used to relieve skin itchiness and rashes. In this study, Aloe vera is commonly cut and applied on open wounds to facilitate healing. Topical aloe gel may help to heal burns and abrasions (NCCAM, 2014). However, contradictory results have also been reported. A study has shown that aloe dermal wound gel is associated with a delay in wound healing (Schmidt and Greenspoon, 1991). Also, aloe gel has not been shown to prevent burns from radiation therapy (NCCAM, 2014). Combination ingredients were often added to the preparation to complement the therapeutic effect of other plants. Many users believed that fresh plants were “cooler” in nature, in comparison to their dried counterparts. Hence, Chinese red dates (35 preparations) were often present in brewed herbal preparations to counter the “cooling effect” of the plants. In Chinese herbal text, red dates were always mentioned for strengthening the spleen and stomach Qi (energy)—which in turns helps to digest food, tonify blood and tranquilise the mind (Chinese Pharmacopoeia 2010; Xie, 1996). Uniquely, black/brown sugar (49 preparations) was purported to neutralise toxins and to enhance the efficacy of the herbs. Other common forms of sweeteners added to enhance the taste of preparations include honey (22 preparations), rock sugar 冰糖 (23 preparations) and golden thread preserved dates 金 丝蜜枣 (7 preparations). Rock sugar was considered a tonic by many users as it strengthens and cools the constitution. A popular folk remedy in Singapore and Malaysia to treat and prevent cancer involved blending the fresh leaves of Clinacanthus nutans with a green apple (23 preparations), with many who reported that the green apple can mask the grassy smell and taste of the leaves. In this study, fresh leaves ranging from 20 to 50 pieces were blended and drunk each time by the participants. The recommended dose is currently debatable and unknown. Some herbal preparations were ingested with special attention to the timing of food intake. Most of the preparations (248 preparations) were taken without regards to timing of food intake, whereas 85 preparations were taken after food to minimise stomach irritation. On the other hand, 50 herbal preparations were taken before food mainly for enhanced absorption. A total of 21 herbal preparations were taken with a meal as salad or vegetable dish, of which examples of plant species were Pereskia bleo, Parkia speciosa and Mormodica charantia. Besides being used

for their nutritional properties, herbs such as Artemisia argyi and Ocimum basilicum were also used as ingredients in food to impart flavour. 3.5. Undesirable effects and plant toxicity Our study also looked at the various unwanted effects reported by the users. A majority of the users (171 users, 85.5%) stated that they did not experience any undesirable effect after ingesting fresh medicinal plants. Others (28 users, 14.0%) reported having experienced mild, self-resolving symptoms with a total of 16 species of plants. There was no report of any significant adverse effect which required medical attention, except in one incident of hyponatremia. However, it was not clinically confirmed if the adverse effect indeed arose from using the plant, Clinacanthus nutans. None of the user reported any toxic effect. 3.6. Reported outcomes The participants were asked about the outcome of the plant usage. The reported outcomes are shown in Table 5. A majority of the participants reported that their conditions improved or symptomatic relief was achieved (118, 59.0%) while 98 participants (49.0%) achieved a sense of wellbeing. A minority of 5 users informed that their medical condition and state of well-being worsened after taking the plants, prompting them to stop the usage. Some participants failed to experience any effect from using the plants. Our finding is in agreement with other studies on the usage of CAM which have shown that the majority of CAM users appeared satisfied with their therapies (Oldendick et al., 2000; Rafferty et al., 2002). The results of this study suggest that fresh medicinal plants have a role to play in healthcare even in modern society where allopathic medicine is the primary form of healthcare and is readily available. As the efficacy of many medicinal plants has not yet been proven in scientific studies and multi-centred, placebo controlled, double-blind clinical trials have not been carried out, more research is warranted. Health professionals and the general public should be aware of the usage of such plants by patients for therapeutic effects as well as by healthy individuals for prophylactic purposes and health maintenance. Qualified practitioners should be consulted with regards to the safe and appropriate use of these plants.

4. Conclusions Two hundred participants who used a total of 104 fresh medicinal plant species within the last five years were successfully interviewed. To the best of our knowledge, this is the first survey of its kind whereby the users are interviewed in person for details of the plant usage using an Institutional Review Board approved protocol. The extensive knowledge recorded is important to show and to systematically document the ethnic use of fresh medicinal plants for their pharmacological effects in a modern society like Singapore. This knowledge will remain an important cultural legacy for future generations and will serve as a useful resource for future drug discovery efforts.

Acknowledgements The authors thank all the study participants who selflessly shared their experiences, the National University of Singapore (NUS) Academic Research Fund (R-148-000-137-112 to KHL), the NUS Provost Industrial PhD Programme Research Scholarship (to

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

SYY) and Singapore International Graduate Award (to SZ). The authors declare no conflict of interest.

References Abdul-Wahab, I.R., Guilhon, C.C., Fernandes, P.D., Boylan, F., 2012. Anti-nociceptive activity of Pereskia bleo Kunth (Cactaceae) leaves extracts. Journal of Ethnopharmacology 144 (3), 741–746. Anilakumar, K.R., Sudarshanakrishna, K.R., Chandramohan, G., Ilaiyaraja, N., Khanum, F., Bawa, A.S., 2010. Effect of Aloe vera gel extract on antioxidant enzymes and azoxymethane-induced oxidative stress in rats. Indian Journal of Experimental Biology 48 (8), 837–842. Astin, J.A., 1998. Why patients use alternative medicine: results of a national study. The Journal of the American Medical Association 279, 1548–1553. Atiba, A., Ueno, H., Uzuka, Y., 2011. The effect of aloe vera oral administration on cutaneous wound healing in type 2 diabetic rats. Journal of Veterinary Medical Science 73 (5), 583–589. Bryer, E., 2005. A literature review of the effectiveness of ginger in alleviating mildto-moderate nausea and vomiting of pregnancy. Journal of Midwifery & Women's Health 50, e1–e3. Cárdenas, C., Quesada, A.R., Medina, M.A., 2006. Evaluation of the anti-angiogenic effect of aloe-emodin. Cellular and Molecular Life Sciences 63 (24), 3083–3089. Chaiyakunapruk, N., Kitikannakorn, N., Nathisuwan, S., Leeprakobboon, K., Leelasettagool, C., 2006. The efficacy of ginger for the prevention of postoperative nausea and vomiting: a meta-analysis. American Journal of Obstetrics and Gynecology 194, 95–99. Chan, A., Lin, T.H., Shih, V., Ching, T.H., Chiang, J., 2012. Clinical outcomes for cancer patients using complementary and alternative medicine. Alternative Therapies in Health and Medicine 18 (1), 12–17. Chaudhary, G., Saini, M.R., Goyal, P.K., 2007. Chemopreventive potential of Aloe vera against 7,12-dimethylbenz(a)anthracene induced skin papillomagenesis in mice. Integrative Cancer Therapies 6 (4), 405–412. Chinese Pharmacopoeia. Pharmacopoeia of the People's Republic of China. Beijing, China: China Medical Science Press; 1, 2010. Choi, S., Kim, K.W., Choi, J.S., Han, S.T., Park, Y.I., Lee, S.K., Kim, J.S., Chung, M.H., 2002. Angiogenic activity of beta-sitosterol in the ischaemia/reperfusiondamaged brain of Mongolian gerbil. Planta Medica 68 (4), 330–335. Chong, H.Z., Rahmat, A., Yeap, S.K., Md Akim, A., Alitheen, N.B., Othman, F., Gwendoline-Ee, C.L., 2012. In vitro cytotoxicity of Strobilanthes crispus ethanol extract on hormone dependent human breast adenocarcinoma MCF-7 cell. BMC Complementary & Alternative Medicine 12, 35. Dat, A.D., Poon, F., Pham, K.B.T., Doust, J., 2012. Aloe vera for treating acute and chronic wounds. Cochrane Database of Systematic Reviews 2, CD008762. Dutta, A., Sarkar, D., Gurib-Fakim, A., Mandal, C., Chatterjee, M., 2008. In vitro and in vivo activity of Aloe vera leaf exudate in experimental visceral leishmaniasis. Parasitology Research 102 (6), 1235–1242. eFloras, 2013. 〈http://www.efloras.org〉 (accessed 26.03.13.). El-Shemy, H.A., Aboul-Soud, M.A.M., Nassr-Allah, A.A., Aboul-Enein, K.M., Kabash, A., Yagi, A., 2010. Antitumor properties and modulation of antioxidant enzymes' activity by Aloe vera leaf active principles isolated via supercritical carbon dioxide extraction. Current Medicinal Chemistry 17 (2), 129–138. Er, H.M., Cheng, E.H., Radhakrishnan, A.K., 2007. Anti-proliferative and mutagenic activities of aqueous and methanol extracts of leaves from Pereskia bleo (Kunth) DC (Cactaceae). Journal of Ethnopharmacology 113 (3), 448–456. Ernst, E., Pittler, M.H., 2000. Efficacy of ginger for nausea and vomiting: a systematic review of randomized clinical trials. British Journal of Anaesthesia 84, 367–371. Fadzelly, A.B.M., Asmah, R., Fauziah, O., 2006. Effects of Strobilanthes crispus tea aqueous extracts on glucose and lipid profile in normal and streptozotocininduced hyperglycemic rats. Plant Foods for Human Nutrition 61 (1), 7–12. Feily, A., Namazi, M.R., 2009. Aloe vera in dermatology: a brief review. Giornale Italiano di Dermatologia Venereologia 144 (1), 85–91. Germplasm Resources Information Network's (GRIN), 2013. 〈http://www.ars-grin. gov/〉 (accessed 26.03.13.). Goyal, P.K., Gehlot, P., 2009. Radioprotective effects of Aloe vera leaf extract on Swiss albino mice against whole-body gamma irradiation. Journal of Environmental Pathology, Toxicology and Oncology 28 (1), 53–61. Grzanna, R., Lindmark, L., Frondoza, C.G., 2005. Ginger – an herbal medicinal product with broad anti-inflammatory actions. Journal of Medicinal Food 8, 125–132. Hill, A.F., 1989. Economic Botany: A Text Book of Useful Plants and Plant Products, 2nd ed. McGraw Hill Book Company, Inc., New York. Hosseinimehr, S.J., Khorasani, G., Azadbakht, M., Zamani, P., Ghasemi, M., Ahmadi, A., 2010. Effect of aloe cream versus silver sulfadiazine for healing burn wounds in rats. Acta Dermatovenerologica Croatica 18 (1), 2–7. Hu, Y., Xu, J., Hu, Q., 2003. Evaluation of antioxidant potential of Aloe vera (Aloe barbadensis miller) extracts. Journal of Agricultural and Food Chemistry 51 (26), 7788–7791. Inpanya, P., Faikrua, A., Ounaroon, A., Sittichokechaiwut, A., Viyoch, J., 2012. Effects of the blended fibroin/aloe gel film on wound healing in streptozotocininduced diabetic rats. Biomedical Materials 7 (3), 035008. International Monetary Fund (IMF), 2014. World Economic Outlook Database. Database updated on 8 April 2014 (accessed 10.04.14.).

1465

Iqbal, M., Shah, M.D., Lie, C.A., San, C.K., 2010. Strobilanthes crispus attenuates renal carcinogen, iron nitrilotriacetate (Fe-NTA)-mediated oxidative damage of lipids and DNA. Molecular and Cellular Biochemistry 341 (1–2), 271–277. Ismail, M., Manickam, E., Danial, A.M., Rahmat, A., Yahaya, A., 2000. Chemical composition and antioxidant activity of Strobilanthes crispus leaf extract. The Journal of Nutritional Biochemistry 11 (11–12), 536–542. Janwitayanuchit, W., Suwanborirux, K., Patarapanich, C., Pummangura, S., Lipipun, V., Vilaivan, T., 2003. Synthesis and anti-herpes simplex viral activity of monoglycosyl diglycerides. Phytochemistry 64 (7), 1253–1264. Khor, P.Y., Abdullah, M.S.B., Syafri, S., Kula Raju, S., Che Yahya, C.A.H., 2013. A preliminary survey on the medicinal uses and effectiveness of Pereskia bleo used by people of three villages in the State of Kelantan, Malaysia. International Journal of Herbal Medicine 1 (3), 1–4. Koh, H.L., Chua, T.K., Tan, C.H., 2010. A Guide to Medicinal Plants: An illustrated, Scientific and Medicinal Approach. World Scientific, Singapore p. 311. Koh, H.L., Ng, H.L., Teo, H.H., 2004. A survey on knowledge, attitudes and usage of complementary and alternative medicine in Singapore. Asia Pacific Biotech News 8, 1266–1270. Kongkaew, C., Chaiyakunapruk, N., 2011. Efficacy of Clinacanthus nutans extracts in patients with herpes infection: systematic review and meta-analysis of randomised clinical trials. Complementary Therapies in Medicine 19 (1), 47–53. Kunsorn, P., Ruangrungsi, N., Lipipun, V., Khanboon, A., Rungsihirunrat, K., Chaijaroenkul, W., 2013. The identities and anti-herpes simplex virus activity of Clinacanthus nutans and Clinacanthus siamensis. Asian Pacific Journal of Tropical Biomedicine 3 (4), 284–290. Kuo, P.L., Lin, T.C., Lin, C.C., 2002. The antiproliferative activity of aloe-emodin is through p53-dependent and p21-dependent apoptotic pathway in human hepatoma cell lines. Life Sciences 71 (16), 1879–1892. Kwek, Y.C., Tan, T.W.H., Richard, T.C., 2009. A checklist of the total vascular plant flora of Singapore: native, naturalised and cultivated species. Raffles Museum of Biodiversity Research. National University of Singapore, Singapore (accessed 2.01.14.). Lee, G.B.W., Charn, T.C., Chew, Z.H., Ng, T.P., 2004. Complementary and alternative medicine use in patients with chronic diseases in primary care is associated with perceived quality of care and cultural beliefs. Family Practice 21, 654–660. Lee, M.J., Lee, O.H., Yoon, S.H., Lee, S.K., Chung, M.H., Park, Y.I., Sung, C.K., Choi, J.S., Kim, K.W., 1998. In vitro angiogenic activity of Aloe vera gel on calf pulmonary artery endothelial (CPAE) cells. Archives of Pharmacal Research 21 (3), 260–265. Lim, J., Wong, M., Chan, M.Y., Tan, A.M., Rajalingam, V., Lim, L.P., Lou, J., Tan, C.L., 2006. Use of complementary and alternative medicine in paediatric oncology patients in Singapore. Annals Academy of Medicine Singapore 35 (11), 753–758. Malek, S.N.A., Shin, S.K., Wahab, N.A., Yaacob, H., 2009. Cytotoxic components of Pereskia bleo (Kunth) DC. (Cactaceae) leaves. Molecules 14 (5), 1713–1724. Men, J., Guo, L., 2010. A General Introduction to Traditional Chinese Medicine. Science Press, United States. Ministry of Health Singapore, 2012. Disease burden. 〈http://www.moh.gov.sg/ content/moh_web/home/statistics/Health_Facts_Singapore/Disease_Burden.html〉 (accessed 3.11.13.). Moon, E.J., Lee, Y.M., Lee, O.H., Lee, M.J., Lee, S.K., Chung, M.H., Park, Y.I., Sung, C.K., Choi, J.S., Kim, K.W., 1999. A novel angiogenic factor derived from Aloe vera gel: beta-sitosterol, a plant sterol. Angiogenesis 3 (2), 117–123. National Center for Complementary and Alternative Medicine (NCCAM), 2014.U.S. Department of Health & Human Services, National Institutes of Health. 〈http:// nccam.nih.gov/〉 (accessed 20.02.14.). National Parks Board, 2010. 〈http://www.nparks.gov.sg/〉 (accessed 26.03.13.). Nićiforović, A., Adzić, M., Spasić, S.D., Radojcić, M.B., 2007. Antitumor effects of a natural anthracycline analog (Aloin) involve altered activity of antioxidant enzymes in HeLaS3 cells. Cancer Biology & Therapy 6 (8), 1200–1205. Oldendick, R., Coker, A.L., Wieland, D., Raymond, J.I., Probst, J.C., Schell, B.J., Stopskopf, C.H., 2000. Population-based survey of complementary and alternative medicine usage, patient satisfaction, and physician involvement. Southern Medical Journal 93, 375–381. Park, M.Y., Kwon, H.J., Sung, M.K., 2009. Evaluation of aloin and aloe-emodin as anti-inflammatory agents in aloe by using murine macrophages. Bioscience, Biotechnology, and Biochemistry 73 (4), 828–832. Popadic, D., Savic, E., Ramic, Z., Djordjevic, V., Trajkovic, V., Medenica, L., Popadic, S., 2012. Aloe-emodin inhibits proliferation of adult human keratinocytes in vitro. Journal of Cosmetic Science 63 (5), 297–302. Rafferty, A.P., McGee, H.B., Miller, C.E., Reyes, M., 2002. Prevalence of complementary and alternative medicine use: state-specific estimates from the 2001 behavioral risk factor surveillance system. American Journal of Public Health 92, 1598–1600. Richardson, J., Smith, J.E., McIntyre, M., Thomas, R., Pilkington, K., 2005. Aloe vera for preventing radiation-induced skin reactions: a systematic literature review. Clinical Oncology 17, 478–484. http://dx.doi.org/10.1016/j.clon.2005.04.013. Rishi, P., Rampuria, A., Tewari, R., Koul, A., 2008. Phytomodulatory potentials of Aloe vera against Salmonella OmpR-mediated inflammation. Phytotherapy Research 22 (8), 1075–1082. Rubin, R., Gold, S.A., 2002. Tea Chings: The Tea and Herb Companion—Appreciating the Varietals and Virtues of Fine Tea and Herbs, second ed. Newmarket Press, New York p. 116. Saini, M., Goyal, P.K., Chaudhary, G., 2010. Anti-tumor activity of Aloe vera against DMBA/croton oil-induced skin papillomagenesis in Swiss albino mice. Journal of Environmental Pathology, Toxicology and Oncolology 29 (2), 127–135.

1466

Y.-Y. Siew et al. / Journal of Ethnopharmacology 155 (2014) 1450–1466

Sakdarat, S., Shuyprom, A., Pientong, C., Ekalaksananan, T., Thongchai, S., 2009. Bioactive constituents from the leaves of Clinacanthus nutans Lindau. Bioorganic & Medicinal Chemistry 17 (5), 1857–1860. Schmidt, J., Greenspoon, J., 1991. Aloe vera dermal wound gel is associated with a delay in wound healing. Obstetrics & Gynecology 78, 115–117. Shukla, Y., Singh, M., 2007. Cancer preventive properties of ginger: a brief review. Food and Chemical Toxicology 45, 683–690. Sim, K.S., Sri Nurestri, A.M., Sinniah, S.K., Kim, K.H., Norhanom, A.W., 2010. Acute oral toxicity of Pereskia bleo and Pereskia grandifolia in mice. Pharmacognosy Magazine 6 (21), 67–70. Singapore Department of Statistics, 2013a. Singapore in Figures 2013. 〈http://www. singstat.gov.sg/publications/publications_and_papers/reference/sif2013.pdf〉 (accessed 15.04.14.). Singapore Department of Statistics, 2013b. Key Household Income Trends, 2013. 〈http://www.singstat.gov.sg/Publications/publications_and_papers/househol d_income_and_expenditure/pp-s20.pdf〉 (accessed 15.04.14.). Sofowara, A., 1982. Medicinal Plants and Traditional Medicinal in Africa. John Wiley and Sons, New York p. 256. Suboj, P., Babykutty, S., Valiyaparambil Gopi, D.R., Nair, R.S., Srinivas, P., Gopala, S., 2012a. Aloe emodin inhibits colon cancer cell migration/angiogenesis by downregulating MMP-2/9, RhoB and VEGF via reduced DNA binding activity of NF-κB. European Journal of Pharmaceutical Sciences 45 (5), 581–591. Suboj, P., Babykutty, S., Srinivas, P., Gopala, S., 2012b. Aloe emodin induces G2/M cell cycle arrest and apoptosis via activation of caspase-6 in human colon cancer cells. Pharmacology 89 (1–2), 91–98. Surjushe, A., Vasani, R., Saple, D.G., 2008. Aloe vera: a short review. Indian Journal of Dermatology 53, 163–166. http://dx.doi.org/10.4103/0019-5154.44785. Tabolacci, C., Lentini, A., Mattioli, P., Provenzano, B., Oliverio, S., Carlomosti, F., Beninati, S., 2010. Antitumor properties of aloe-emodin and induction of transglutaminase 2 activity in B16-F10 melanoma cells. Life Sciences 87 (9–10), 316–324. Tabolacci, C., Oliverio, S., Lentini, A., Rossi, S., Galbiati, A., Montesano, C., Mattioli, P., Provenzano, B., Facchiano, F., Beninati, S., 2011. Aloe-emodin as antiproliferative and differentiating agent on human U937 monoblastic leukaemia cells. Life Sciences 89 (21–22), 812–820. Tabolacci, C., Rossi, S., Lentini, A., Provenzano, B., Turcano, L., Facchiano, F., Beninati, S., 2013. Aloin enhances cisplatin antineoplastic activity in B16-F10 melanoma cells by transglutaminase-induced differentiation. Amino Acids 44 (1), 293–300. Takzare, N., Hosseini, M.J., Hasanzadeh, G., Mortazavi, H., Takzare, A., Habibi, P., 2009. Influence of Aloe Vera gel on dermal wound healing process in rat. Toxicology Mechanisms and Methods 19 (1), 73–77. Tan, M.L., Sulaiman, S.F., Najimuddin, N., Samian, M.R., Muhammad, T.S.T., 2005. Methanolic extract of Pereskia bleo (Kunth) DC. (Cactaceae) induces apoptosis in breast carcinoma, T47-D cell line. Journal of Ethnopharmacology 96 (1–2), 287–294. The International Plant Names Index, 2012. 〈http://www.ipni.org/〉 (accessed 26.03.13.). The Plant List, 2010. Version 1. 〈http://www.theplantlist.org/〉 (accessed 01.01.14.).

Tropicos.org. Missouri Botanical Garden, 2013. 〈http://www.tropicos.org〉 (assessed 26.03.13.). Vachirayonstien, T., Promkhatkaew, D., Bunjob, M., Chueyprom, A., Chavalittumrong, P., Sawanpanyalert, P., 2010. Molecular evaluation of extracellular activity of medicinal herb Clinacanthus nutans against herpes simplex virus type-2. Natural Product Research 24 (3), 236–245. Wang, W.H., Wang, Z.M., 2005. Studies of commonly used traditional medicineginger. Zhongguo Zhongyao Zazhi 30 (20), 1569–1573. Wanikiat, P., Panthong, A., Sujayanon, P., Yoosook, C., Rossi, A.G., Reutrakul, V., 2008. The anti-inflammatory effects and the inhibition of neutrophil responsiveness by Barleria lupulina and Clinacanthus nutans extracts. Journal of Ethnopharmacology 116 (2), 234–244. White, B., 2007. Ginger: an overview. American Family Physician 75 (11), 1689–1691. Wiseman, N., 1995. Fundamentals of Chinese Medicine. Paradigm. Publications, Brookline, Massachusetts, U.S.A.. Wong, K.C., Tan, G.L., 1994. Steam volatile constituents of the aerial parts of Paederia foetida L. Flavour and Fragrance Journal 9 (1), 25–28. Woo, S.W., Nan, J.X., Lee, S.H., Park, E.J., Zhao, Y.Z., Sohn, D.H., 2002. Aloe emodin suppresses myofibroblastic differentiation of rat hepatic stellate cells in primary culture. Pharmacology & Toxicology 90 (4), 193–198. World Health Organisation (WHO), 2000. WHO Traditional Medicine Strategy 2002–2005. 〈http://www.wpro.who.int/health_technology/book_who_traditio nal_medicine_strategy_2002_2005.pdf〉 (accessed 14.04.14.). World Health Organisation (WHO), 2014. International Classification of Diseases (ICD) 〈http://www.who.int/classifications/icd/en/〉 (accessed 14.04.14.). Xie, Z.W., 1996. Compilation of Chinese Herbal Medicine. Beijing, People's Medical Publishing House Co. Ltd. p. 1050. Yaacob, N.S., Hamzah, N., Kamal, Nik Mohamed, Zainal Abidin, N.N., Lai, S.A., Navaratnam, C.S., Norazmi, M.N., V., 2010. Anticancer activity of a sub-fraction of dichloromethane extract of Strobilanthes crispus on human breast and prostate cancer cells in vitro. BMC Complementary & Alternative Medicine 10, 42. Yagi, A., Kabash, A., Okamura, N., Haraguchi, H., Moustafa, S.M., Khalifa, T.I., 2002. Antioxidant, free radical scavenging and anti-inflammatory effects of aloesin derivatives in Aloe vera. Planta Medica 68 (11), 957–960. Yong, Y.K., Tan, J.J., Teh, S.S., Mah, S.H., Ee, G.C., Chiong, H.S., Ahmad, Z., 2013. Clinacanthus nutans extracts are antioxidant with antiproliferative effect on cultured human cancer cell lines. Evidence-Based Complementary and Alternative Medicine 2013, 462751. Zareisedehizadeh S., Tan C.H. and Koh H.L., A review of botanical characteristics, traditional usage, chemical components, pharmacological activities, and safety of Pereskia bleo (Kunth) DC, Evidence-Based Complementary and Alternative Medicine 2014, 2014, 326107. Zhang, X.F., Wang, H.M., Song, Y.L., Nie, L.H., Wang, L.F., Liu, B., Shen, P.P., Liu, Y., 2006. Isolation, structure elucidation, antioxidative and immunomodulatory properties of two novel dihydrocoumarins from Aloe vera. Bioorganic & Medicinal Chemistry Letters 16 (4), 949–953. Zhao, Z.Z., Xiao, P.G., 2009. Encyclopedia of Medicinal Plants. Hong Kong Jockey Club Institute of Chinese Medicine Limited, Hong Kong.

Ethnobotanical survey of usage of fresh medicinal plants in Singapore.

The use of medicinal plants in human health has been documented since ancient times and they provide a useful source of new therapeutics. In Singapore...
600KB Sizes 5 Downloads 17 Views