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Natural Product Research: Formerly Natural Product Letters Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/gnpl20
Chemical composition, antimicrobial and antioxidant activities of the essential oil of Psammogetoncanescens a
a
Mohsen Kazemi & Hajar Rostami a
Department of Horticultural Science, Faculty of Agricultural Science and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran, Iran Published online: 26 Aug 2014.
To cite this article: Mohsen Kazemi & Hajar Rostami (2014): Chemical composition, antimicrobial and antioxidant activities of the essential oil of Psammogetoncanescens, Natural Product Research: Formerly Natural Product Letters, DOI: 10.1080/14786419.2014.951357 To link to this article: http://dx.doi.org/10.1080/14786419.2014.951357
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
Natural Product Research, 2014 http://dx.doi.org/10.1080/14786419.2014.951357
SHORT COMMUNICATION Chemical composition, antimicrobial and antioxidant activities of the essential oil of Psammogeton canescens Mohsen Kazemi* and Hajar Rostami
Downloaded by [Florida Institute of Technology] at 14:22 26 August 2014
Department of Horticultural Science, Faculty of Agricultural Science and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran, Iran (Received 24 July 2014; final version received 31 July 2014) This study reports the chemical composition, antimicrobial activity and antioxidant properties of Psammogeton canescens essential oil (EO) and its main compounds. The EO was obtained from the aerial parts of P. canescens by hydrodistillation and analysed by using GC/MS. The main constituent was b-bisabolene (25%), followed by a-pinene (20%), apiole (15.34%), g-terpinene (7.34%), p-cymene (5.35%), b-pinene (5.41%), camphene (5.12%), dill apiole (5%), myrcene (4.54%), colchicine (0.56), sylvestrene (0.56%), b-caryophyllene (0.45%), caryophyllene oxide (0.43%), (Z)-b-farnesene (0.32%), cembrene (0.21%), folic acid (0.21%), germacrene D (0.14) and bsesquiphellandrene (0.13). b-Bisabolene exhibited strong antioxidant activity (14 ^ 0.8 mg/mL). The EO of P. canescens was particularly active against Candida albicans and Escherichia coli, with the lowest minimum inhibitory concentration and minimum bactericidal/fungicidal concentration values. In conclusion, these results support the use of the EO and its main compounds for their antioxidant properties and antimicrobial activity. Keywords: Psammogeton canescens; chemical composition; antioxidant activity; antimicrobial activity
1. Introduction Natural products have played an important role worldwide in the treatment and prevention of fungal infections and pathologies with a strong inflammatory component, with several studies referring the therapeutic properties of these metabolites (Adorjan & Buchbauer 2010). Since ancient times, herbs and spices have been used in different types of food to improve flavours and are well known for their antioxidant and antimicrobial capacities (Madsen & Bertelsen 1995). Recent research is now directed towards finding naturally occurring antimicrobials and antioxidants of plant origin. Among these, the antioxidant properties of many aromatic and medicinal plants have been shown to be effective in retarding the process of lipid peroxidation in oils and fatty foods and have gained the interest of many research groups (Kulisic et al. 2004). The family Umbelliferae is an extended family comprising 300 genera and more than 3000 species. For the family Umbelliferae, Iran is a major centre of diversification. The genus Psammogeton Edyew., which belongs to the Umbelliferae family, is found in areas of Central Asia. This genus consists of six species widespread in the sandy dunes of deserts. Among the four species present in Iran, Psammogeton canescens (DC.) Vatke is distributed in regions of central Iran (Rahimi-Nasrabadi et al. 2009). In Iran, dried fruits and leaves of this plant are added to soup, cheese and yoghurt for flavouring and fragrances. Also, dried fruit of P. canescens is
*Corresponding author. Email: [email protected] q 2014 Taylor & Francis
2
M. Kazemi and H. Rostami
traditionally used for the treatment of stomach ache in Iranian folk medicine (Zargari 1991). However, studies to support antimicrobial properties of the volatile oil have not yet been reported. The main objectives of this study were to evaluate the antioxidant and antimicrobial properties of the essential oil (EO) from P. canescens aerial parts and to determine the compounds that contributed to the effects.
Downloaded by [Florida Institute of Technology] at 14:22 26 August 2014
2. Results and discussion 2.1. Chemical composition of EO The EO from the aerial parts of Iranian P. canescens obtained using hydrodistillation was isolated in high yield (0.8%). Results of GC/MS analysis of the EO (Table S1) indicate that the EO was characterised mainly by sesquiterpenoids. The major constituent of the oil was b-bisabolene, with a relative concentration of 25%. The GC/MS analysis of P. canescens oil revealed 18 compounds representing 96.11% of the total oil; b-bisabolene was the main constituent (25%), followed by a-pinene (20%), apiole (15.34%), g-terpinene (7.34%), p-cymene (5.35%), b-pinene (5.41%), camphene (5.12%), dill apiole (5%), myrcene (4.54%), colchicine (0.56), sylvestrene (0.56%), b-caryophyllene (0.45%), caryophyllene oxide (0.43%), (Z)-b-farnesene (0.32%), cembrene (0.21%), folic acid (0.21%), germacrene D (0.14) and b-sesquiphellandrene (0.13). Previous studies have shown that b-bisabolene (33.35%), apiole (28.34%), a-pinene (11.86%) and dill apiole (8.17%) were major constituents in the volatile oil of P. canescens (Rahimi-Nasrabadi et al. 2009). According to the report of Karim and Bhatty (1977), limonane (58.10%) and elimicin (11.8%) were among the main components of P. canescens, whereas they were not detected in this study. Our results reinforce previous data on the variability in the volatile oils of the aerial parts, depending on the origin of the samples, environmental and climatic conditions. The high level of p-cymene in the EO could contribute to the valorisation of Iranian P. canescens species, since this monoterpene is of great importance in industry as an intermediate for the synthesis of fragrances, pharmaceuticals and herbicides. 2.2. Antimicrobial activity The in vitro antimicrobial activities of P. canescens EO against the studied microorganisms were assessed by the minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) (Table S2). According to the results given in Table S2, P. canescens EO exhibited significant antimicrobial activity against all tested strains. Inhibition values were in the following range: MIC 2 ^ 0.00 (Escherichia coli and Bacillus cereus) 2 10 ^ 0.5 mg/mL (Pseudomonas aeruginosa) and MBC 2.5 ^ 0.00 mg/L (E. coli) 2 10.00 mg/mL (Staphylococcus aureus) for bacteria, and MIC 1 ^ 0.5 (Candida albicans) 2 5 ^ 0.5 mg/mL (Candida parapsilosis) and MFC 1 ^ 0.5 (C. albicans) 2 5 ^ 0.5 mg/mL (C. parapsilosis) for fungi. Results obtained from MIC and MBC/MFC indicated that C. albicans and E. coli are the most sensitive microorganisms tested, with the lowest MIC and MBC/MFC values (Table S2) in the presence of the oil isolated from P. canescens. Comparing the results of EOs with that of standard, streptomycin and fluconazole, it was concluded that the oils possess more potent antioral-pathogen activity. The EOs of P. canescens expressed higher antibacterial activity than both antibiotics tested. Overall, the EOs of P. canescens exhibited significant antibacterial activity, especially against E. coli and C. albicans. The oils also efficiently inhibited the growth of Candida spp., which is crucial since C. albicans, Candida tropicalis and C. parapsilosis proved to be involved in the disease course, and together with C. albicans represent more than 80% of human cavity clinical isolates (Akpan & Morgan 2002). It is clear from these studies that these secondary plant metabolites have potential uses in medical procedures and applications in the cosmetic, pharmaceutical and food industries (Lo Cantore et al. 2004). Biological activity of the
Natural Product Research
3
EOs depends on their chemical composition which is determined by the genotype and influenced by environmental and agronomic conditions (Marotti et al. 1992). Correlation between the achieved antimicrobial activity of selected EOs of P. canescens and their chemical composition insinuates that the activity may be easily ascribed to phenolic compound b-bisabolene and apinene present in high percentage in the oils. In our study, most of the antimicrobial activity in EOs from P. canescens appears to be associated with phenolic compounds (b-bisabolene and apinene).
Downloaded by [Florida Institute of Technology] at 14:22 26 August 2014
2.3. Antioxidant activity Antioxidant activity is a complex process usually occurring through several mechanisms. Due to its complexity, the evaluation of the antioxidant activity for pure compounds or extracts should be carried out by more than one test method (Aruoma 2003). The lower IC50 value indicates a stronger ability of the extract to act as a DPPH scavenger while the higher IC50 value indicates a lower scavenging activity of the scavengers as more scavengers were required to achieve 50% scavenging reaction. The results presented in Table S3 revealed that P. canescens EO and its main constituents exhibited a remarkable activity. In particular, b-bisabolene exhibited clearly a higher activity (IC50 ¼ 14 ^ 0.8 mg/mL) followed by P. canescens EO (15 ^ 0.3 mg/mL) and a-pinene (14.4 ^ 0.7 mg/mL) (Table S3), while the activities of other terpenoids were weak. The positive controls BHT and ascorbic acid exhibited IC50 values equal to 14 ^ 0.5 mg/mL and 10 ^ 0.3 mg/mL, respectively. The monoterpene hydrocarbons, p-cymene and b-pinene were inactive (Table S3), despite previous reports of their in vitro antioxidant activities (Ruberto & Baratta 2000). Because of high antioxidant and free radical-scavenging activities of P. canescens EO, further investigation was carried out to identify its active constituents. Therefore, a preliminary screening was initially carried out using the dot-blot DPPHz staining method on PTLC. As the EO presented a significant antioxidant activity in the assays and bioautography test, it was subjected to the PTLC for isolation of the active compounds. Components identified and their antioxidant activity relative percentages have been shown in Table S4. The major compound found in the active band was b-bisabolene (86%). According to these results, there is a relationship between total phenol contents and antioxidant activity. Phenolic compounds, biologically active components, are the main agents that can donate hydrogen to free radicals and thus break the chain reaction of lipid oxidation at the first initiation step. This high potential of phenolic compounds to scavenge radicals may be explained by their phenolic hydroxyl groups (Oke et al. 2009). 3. Conclusion Our data indicate that the EO extracted from P. canescens exhibits potent biological activities, which support their use in traditional medicine. Moreover, results regarding the bioactivities of the main volatile components suggest that the observed activities of the EO are connected to its chemical composition, where b-bisabolene and a-pinene have been found to be the most active compounds. There was a good correlation between total phenol content and antimicrobial and antioxidant capacity of the extracts. In conclusion, P. canescens extracts appear to contain compounds with antimicrobial and antioxidant activities. Supplementary material Experimental materials relating to this article are available online, alongside Tables S1 –S4. References Adorjan B, Buchbauer G. 2010. Biological properties of essential oils: an updated review. Flavour Frag J. 25:407–426.
Downloaded by [Florida Institute of Technology] at 14:22 26 August 2014
4
M. Kazemi and H. Rostami
Akpan A, Morgan R. 2002. Oral candidiasis. Postgrad Med J. 78:455–459. Aruoma OI. 2003. Methodological considerations for characterizing potential antioxidant actions of bioactive components in plant foods. Mutat Res Fund Mol Mech Mutagen. 523:9– 20. Karim A, Bhatty MK. 1977. Studies on the essential oils of the Pakistan species of the family Umbelliferae part 7 Psammogeton canescens khushbui seed oil. Pak J Sci Ind Res. 20:55–56. Kulisic T, Radonic A, Katalinic V, Milos M. 2004. Use of different methods for testing antioxidative activity of oregano essential oil. Food Chem. 85:633–640. Lo Cantore P, Iacobellis NS, De Marco A, Capasso F, Senatore F. 2004. Antibacterial activity of Coriandrum sativum L. and Foeniculum vulgare Millar Var. vulgare (Millar) essential oils. J Agric Food Chem. 52:862–7866. Madsen HL, Bertelsen G. 1995. Spices as antioxidants. Trends Food Sci Technol. 6:271–277. Marotti M, Dellacecca V, Piccaglia R, Giovanelli E. 1992. Agronomic and chemical evaluation of three varieties of Foeniculum vulgare Mill. In: Presented at first world congress on medicinal and aromatic plants for human welfare. Maastricht, The Netherlands; pp. 19–25. Oke F, Aslim B, Ozturk S, Altundag S. 2009. Essential oil composition, antimicrobial and antioxidant activities of Satureja cuneifolia Ten. Food Chem. 112:874–879. Rahimi-Nasrabadi M, Gholivand MB, Batooli H, Vatanara A. 2009. Chemical composition of the essential oil from leaves and flowering aerial parts of Psammogeton canescens (DC.) vake from Iran. J Med Plants. 8:81–86. Ruberto G, Baratta MT. 2000. Antioxidant activity of selected essential oil components in two lipid model systems. Food Chem. 69:167–174. Zargari A. 1991. Medicinal plant. Tehran: Tehran University Publication; p. 942.
Natural Product Research: Formerly Natural Product Letters Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/gnpl20
Chemical composition, antimicrobial and antioxidant activities of the essential oil of Psammogetoncanescens a
a
Mohsen Kazemi & Hajar Rostami a
Department of Horticultural Science, Faculty of Agricultural Science and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran, Iran Published online: 26 Aug 2014.
To cite this article: Mohsen Kazemi & Hajar Rostami (2014): Chemical composition, antimicrobial and antioxidant activities of the essential oil of Psammogetoncanescens, Natural Product Research: Formerly Natural Product Letters, DOI: 10.1080/14786419.2014.951357 To link to this article: http://dx.doi.org/10.1080/14786419.2014.951357
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
Natural Product Research, 2014 http://dx.doi.org/10.1080/14786419.2014.951357
SHORT COMMUNICATION Chemical composition, antimicrobial and antioxidant activities of the essential oil of Psammogeton canescens Mohsen Kazemi* and Hajar Rostami
Downloaded by [Florida Institute of Technology] at 14:22 26 August 2014
Department of Horticultural Science, Faculty of Agricultural Science and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran, Iran (Received 24 July 2014; final version received 31 July 2014) This study reports the chemical composition, antimicrobial activity and antioxidant properties of Psammogeton canescens essential oil (EO) and its main compounds. The EO was obtained from the aerial parts of P. canescens by hydrodistillation and analysed by using GC/MS. The main constituent was b-bisabolene (25%), followed by a-pinene (20%), apiole (15.34%), g-terpinene (7.34%), p-cymene (5.35%), b-pinene (5.41%), camphene (5.12%), dill apiole (5%), myrcene (4.54%), colchicine (0.56), sylvestrene (0.56%), b-caryophyllene (0.45%), caryophyllene oxide (0.43%), (Z)-b-farnesene (0.32%), cembrene (0.21%), folic acid (0.21%), germacrene D (0.14) and bsesquiphellandrene (0.13). b-Bisabolene exhibited strong antioxidant activity (14 ^ 0.8 mg/mL). The EO of P. canescens was particularly active against Candida albicans and Escherichia coli, with the lowest minimum inhibitory concentration and minimum bactericidal/fungicidal concentration values. In conclusion, these results support the use of the EO and its main compounds for their antioxidant properties and antimicrobial activity. Keywords: Psammogeton canescens; chemical composition; antioxidant activity; antimicrobial activity
1. Introduction Natural products have played an important role worldwide in the treatment and prevention of fungal infections and pathologies with a strong inflammatory component, with several studies referring the therapeutic properties of these metabolites (Adorjan & Buchbauer 2010). Since ancient times, herbs and spices have been used in different types of food to improve flavours and are well known for their antioxidant and antimicrobial capacities (Madsen & Bertelsen 1995). Recent research is now directed towards finding naturally occurring antimicrobials and antioxidants of plant origin. Among these, the antioxidant properties of many aromatic and medicinal plants have been shown to be effective in retarding the process of lipid peroxidation in oils and fatty foods and have gained the interest of many research groups (Kulisic et al. 2004). The family Umbelliferae is an extended family comprising 300 genera and more than 3000 species. For the family Umbelliferae, Iran is a major centre of diversification. The genus Psammogeton Edyew., which belongs to the Umbelliferae family, is found in areas of Central Asia. This genus consists of six species widespread in the sandy dunes of deserts. Among the four species present in Iran, Psammogeton canescens (DC.) Vatke is distributed in regions of central Iran (Rahimi-Nasrabadi et al. 2009). In Iran, dried fruits and leaves of this plant are added to soup, cheese and yoghurt for flavouring and fragrances. Also, dried fruit of P. canescens is
*Corresponding author. Email: [email protected] q 2014 Taylor & Francis
2
M. Kazemi and H. Rostami
traditionally used for the treatment of stomach ache in Iranian folk medicine (Zargari 1991). However, studies to support antimicrobial properties of the volatile oil have not yet been reported. The main objectives of this study were to evaluate the antioxidant and antimicrobial properties of the essential oil (EO) from P. canescens aerial parts and to determine the compounds that contributed to the effects.
Downloaded by [Florida Institute of Technology] at 14:22 26 August 2014
2. Results and discussion 2.1. Chemical composition of EO The EO from the aerial parts of Iranian P. canescens obtained using hydrodistillation was isolated in high yield (0.8%). Results of GC/MS analysis of the EO (Table S1) indicate that the EO was characterised mainly by sesquiterpenoids. The major constituent of the oil was b-bisabolene, with a relative concentration of 25%. The GC/MS analysis of P. canescens oil revealed 18 compounds representing 96.11% of the total oil; b-bisabolene was the main constituent (25%), followed by a-pinene (20%), apiole (15.34%), g-terpinene (7.34%), p-cymene (5.35%), b-pinene (5.41%), camphene (5.12%), dill apiole (5%), myrcene (4.54%), colchicine (0.56), sylvestrene (0.56%), b-caryophyllene (0.45%), caryophyllene oxide (0.43%), (Z)-b-farnesene (0.32%), cembrene (0.21%), folic acid (0.21%), germacrene D (0.14) and b-sesquiphellandrene (0.13). Previous studies have shown that b-bisabolene (33.35%), apiole (28.34%), a-pinene (11.86%) and dill apiole (8.17%) were major constituents in the volatile oil of P. canescens (Rahimi-Nasrabadi et al. 2009). According to the report of Karim and Bhatty (1977), limonane (58.10%) and elimicin (11.8%) were among the main components of P. canescens, whereas they were not detected in this study. Our results reinforce previous data on the variability in the volatile oils of the aerial parts, depending on the origin of the samples, environmental and climatic conditions. The high level of p-cymene in the EO could contribute to the valorisation of Iranian P. canescens species, since this monoterpene is of great importance in industry as an intermediate for the synthesis of fragrances, pharmaceuticals and herbicides. 2.2. Antimicrobial activity The in vitro antimicrobial activities of P. canescens EO against the studied microorganisms were assessed by the minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) (Table S2). According to the results given in Table S2, P. canescens EO exhibited significant antimicrobial activity against all tested strains. Inhibition values were in the following range: MIC 2 ^ 0.00 (Escherichia coli and Bacillus cereus) 2 10 ^ 0.5 mg/mL (Pseudomonas aeruginosa) and MBC 2.5 ^ 0.00 mg/L (E. coli) 2 10.00 mg/mL (Staphylococcus aureus) for bacteria, and MIC 1 ^ 0.5 (Candida albicans) 2 5 ^ 0.5 mg/mL (Candida parapsilosis) and MFC 1 ^ 0.5 (C. albicans) 2 5 ^ 0.5 mg/mL (C. parapsilosis) for fungi. Results obtained from MIC and MBC/MFC indicated that C. albicans and E. coli are the most sensitive microorganisms tested, with the lowest MIC and MBC/MFC values (Table S2) in the presence of the oil isolated from P. canescens. Comparing the results of EOs with that of standard, streptomycin and fluconazole, it was concluded that the oils possess more potent antioral-pathogen activity. The EOs of P. canescens expressed higher antibacterial activity than both antibiotics tested. Overall, the EOs of P. canescens exhibited significant antibacterial activity, especially against E. coli and C. albicans. The oils also efficiently inhibited the growth of Candida spp., which is crucial since C. albicans, Candida tropicalis and C. parapsilosis proved to be involved in the disease course, and together with C. albicans represent more than 80% of human cavity clinical isolates (Akpan & Morgan 2002). It is clear from these studies that these secondary plant metabolites have potential uses in medical procedures and applications in the cosmetic, pharmaceutical and food industries (Lo Cantore et al. 2004). Biological activity of the
Natural Product Research
3
EOs depends on their chemical composition which is determined by the genotype and influenced by environmental and agronomic conditions (Marotti et al. 1992). Correlation between the achieved antimicrobial activity of selected EOs of P. canescens and their chemical composition insinuates that the activity may be easily ascribed to phenolic compound b-bisabolene and apinene present in high percentage in the oils. In our study, most of the antimicrobial activity in EOs from P. canescens appears to be associated with phenolic compounds (b-bisabolene and apinene).
Downloaded by [Florida Institute of Technology] at 14:22 26 August 2014
2.3. Antioxidant activity Antioxidant activity is a complex process usually occurring through several mechanisms. Due to its complexity, the evaluation of the antioxidant activity for pure compounds or extracts should be carried out by more than one test method (Aruoma 2003). The lower IC50 value indicates a stronger ability of the extract to act as a DPPH scavenger while the higher IC50 value indicates a lower scavenging activity of the scavengers as more scavengers were required to achieve 50% scavenging reaction. The results presented in Table S3 revealed that P. canescens EO and its main constituents exhibited a remarkable activity. In particular, b-bisabolene exhibited clearly a higher activity (IC50 ¼ 14 ^ 0.8 mg/mL) followed by P. canescens EO (15 ^ 0.3 mg/mL) and a-pinene (14.4 ^ 0.7 mg/mL) (Table S3), while the activities of other terpenoids were weak. The positive controls BHT and ascorbic acid exhibited IC50 values equal to 14 ^ 0.5 mg/mL and 10 ^ 0.3 mg/mL, respectively. The monoterpene hydrocarbons, p-cymene and b-pinene were inactive (Table S3), despite previous reports of their in vitro antioxidant activities (Ruberto & Baratta 2000). Because of high antioxidant and free radical-scavenging activities of P. canescens EO, further investigation was carried out to identify its active constituents. Therefore, a preliminary screening was initially carried out using the dot-blot DPPHz staining method on PTLC. As the EO presented a significant antioxidant activity in the assays and bioautography test, it was subjected to the PTLC for isolation of the active compounds. Components identified and their antioxidant activity relative percentages have been shown in Table S4. The major compound found in the active band was b-bisabolene (86%). According to these results, there is a relationship between total phenol contents and antioxidant activity. Phenolic compounds, biologically active components, are the main agents that can donate hydrogen to free radicals and thus break the chain reaction of lipid oxidation at the first initiation step. This high potential of phenolic compounds to scavenge radicals may be explained by their phenolic hydroxyl groups (Oke et al. 2009). 3. Conclusion Our data indicate that the EO extracted from P. canescens exhibits potent biological activities, which support their use in traditional medicine. Moreover, results regarding the bioactivities of the main volatile components suggest that the observed activities of the EO are connected to its chemical composition, where b-bisabolene and a-pinene have been found to be the most active compounds. There was a good correlation between total phenol content and antimicrobial and antioxidant capacity of the extracts. In conclusion, P. canescens extracts appear to contain compounds with antimicrobial and antioxidant activities. Supplementary material Experimental materials relating to this article are available online, alongside Tables S1 –S4. References Adorjan B, Buchbauer G. 2010. Biological properties of essential oils: an updated review. Flavour Frag J. 25:407–426.
Downloaded by [Florida Institute of Technology] at 14:22 26 August 2014
4
M. Kazemi and H. Rostami
Akpan A, Morgan R. 2002. Oral candidiasis. Postgrad Med J. 78:455–459. Aruoma OI. 2003. Methodological considerations for characterizing potential antioxidant actions of bioactive components in plant foods. Mutat Res Fund Mol Mech Mutagen. 523:9– 20. Karim A, Bhatty MK. 1977. Studies on the essential oils of the Pakistan species of the family Umbelliferae part 7 Psammogeton canescens khushbui seed oil. Pak J Sci Ind Res. 20:55–56. Kulisic T, Radonic A, Katalinic V, Milos M. 2004. Use of different methods for testing antioxidative activity of oregano essential oil. Food Chem. 85:633–640. Lo Cantore P, Iacobellis NS, De Marco A, Capasso F, Senatore F. 2004. Antibacterial activity of Coriandrum sativum L. and Foeniculum vulgare Millar Var. vulgare (Millar) essential oils. J Agric Food Chem. 52:862–7866. Madsen HL, Bertelsen G. 1995. Spices as antioxidants. Trends Food Sci Technol. 6:271–277. Marotti M, Dellacecca V, Piccaglia R, Giovanelli E. 1992. Agronomic and chemical evaluation of three varieties of Foeniculum vulgare Mill. In: Presented at first world congress on medicinal and aromatic plants for human welfare. Maastricht, The Netherlands; pp. 19–25. Oke F, Aslim B, Ozturk S, Altundag S. 2009. Essential oil composition, antimicrobial and antioxidant activities of Satureja cuneifolia Ten. Food Chem. 112:874–879. Rahimi-Nasrabadi M, Gholivand MB, Batooli H, Vatanara A. 2009. Chemical composition of the essential oil from leaves and flowering aerial parts of Psammogeton canescens (DC.) vake from Iran. J Med Plants. 8:81–86. Ruberto G, Baratta MT. 2000. Antioxidant activity of selected essential oil components in two lipid model systems. Food Chem. 69:167–174. Zargari A. 1991. Medicinal plant. Tehran: Tehran University Publication; p. 942.
