PHYTOTHERAPY RESEARCH Phytother. Res. (2014) Published online in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/ptr.5147
Preliminary Safety Evaluation and Biochemical Efficacy of a Carum carvi Extract: Results from a Randomized, Triple-Blind, and Placebo-Controlled Clinical Trial Mahnaz Kazemipoor,1* Che Wan Jasimah Bt Wan Mohamed Radzi,1 Majid Hajifaraji2 and Geoffrey A. Cordell3 1
Department of Science and Technology Studies, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia National Nutrition and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran 1981619573, Iran 3 Natural Products Inc., Evanston, IL 60203, USA 2
Carum carvi L. (Apiaceae) is known as caraway, and its derivatives find wide medicinal use for health purposes, including for gastrointestinal problems and obesity. Since there is inconsistency among the reports on the safety of this plant in humans, this research was aimed at assessing the safety of a characterized caraway aqueous extract (CAE) in a randomized, triple-blind, placebo-controlled study. Seventy, overweight and obese, healthy women were randomly assigned into placebo (n = 35) and plant extract (n = 35) groups. Participants received either 30 ml/day of CAE or placebo. Subjects were examined at baseline and after 12 weeks for changes in heart rate, blood pressure, urine test, 25-item blood chemistries, and general health status. No significant changes of blood pressure, heart rate, urine specific gravity, and serum blood tests were observed between the two groups before and after treatment. However, in the complete blood count test, red blood cell levels were significantly (p < 0.01) increased, and platelet distribution width was significantly decreased after the dietary CAE treatment, as compared with placebo. No negative changes were observed in the general health status of the two groups. This preliminary study suggests that the oral intake of CAE appears to be without any adverse effects at a dosage of 30 ml daily for a period of 12 weeks. Copyright © 2014 John Wiley & Sons, Ltd. Keywords: Carum carvi; caraway aqueous extract; volatile compounds; safety; obesity; phytotherapy.
INTRODUCTION Primary health care based on plant extracts, or isolated natural products, is a popular and sometimes the only treatment approach available to communities all over the world. Indeed, approximately 25% of modern prescription medicines are derived from plants (Farnsworth et al., 1985). Plant-based medications are frequently perceived as being a natural and harmless (safe) form of therapy. However, medicinal plants and their extracts contain numerous phytochemicals, including toxins of exceptional potency, which target a diverse array of human genomic sites. Consequently, their consumption might result in a range of unpleasant reactions, or cause interactions, synergistic or antagonistic, with other medications. Therefore, scientifically establishing the safety of the constituents in a particular preparation must be a primary consideration in the delivery of phytotherapeuticals (Cordell and Colvard 2012). It is important to acknowledge that the safety of a plant cannot be assumed based on historical usage, especially if a different plant part or extraction methodology is * Correspondence to: Mahnaz Kazemipoor, Department of Science and Technology Studies, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia. E-mail: [email protected]
Copyright © 2014 John Wiley & Sons, Ltd.
employed. In addition, there is significant evidence accumulating to show that the ingestion of some plantbased products causes side effects and adverse reactions (Calixto 2000; Ernst 1998; Kazemipoor et al., 2012). Thus, characterization of a plant preparation being biologically evaluated is critical for reproducibility. Caraway, Carum carvi L. (Apiaceae), is a common and ancient medicinal plant. It is recommended as being safe in the form of a spice, as an extract, or as an essential oil, or in combination with other phytochemicals, for the treatment of a range of health problems (Sadowska and Obidoska 2003; Westphal et al., 1996). In addition, a variety of in vitro and in vivo studies have examined a range of different biological and pharmacological activities and health benefits of caraway ingredients. Several animal and human studies have suggested the efficacy of caraway preparations in the treatment of a number of diseases, including gastrointestinal problems (Khayyal et al., 2001; Thompson Coon and Ernst 2002), hyperglycemia (Ene et al., 2007), cancer (Kamaleeswari et al., 2006; Mazaki et al., 2006), and obesity (Kazemipoor et al., 2013). A number of studies have also reported on the safety and tolerability of caraway, along with its hepatoprotective potential (Sadowska and Obidoska 2003; Samojlik et al., 2010; Westphal et al., 1996). Therefore, caraway, by having a promising safety profile, has been recommended as an encouraging ingredient for safe usage as a traditional Received 08 November 2013 Revised 21 February 2014 Accepted 25 February 2014
M. KAZEMIPOOR ET AL.
medicine, and in the pharmaceutical and food manufacturing industries (Johri 2011; Thompson Coon and Ernst 2002). On the other hand, there are also warnings of possible allergic reactions, especially for children below 2 years of age, when the purified volatile oil is consumed (Taheri et al., 2011). Such negative reports are rare, and no scientifically valid clinical trial supports the claims regarding the negative reactions of caraway extract (CE) in humans (Nicotra 2012). Because of the paucity of information, and the concerns regarding the safety and tolerability of CE in humans, a randomized, triple-blind, placebo-controlled clinical trial was conducted to examine the safety and tolerability of aqueous extract of this plant through its effects on blood, and para-clinical, and clinical parameters in a study group receiving a caraway aqueous extract (CAE) compared with a placebo (control) group, over a 12-week experimental period. The anti-obesity property of CAE has been reported in the recent clinical trial. The primary outcomes of this study showed a significant reduction of 1.9 ± 1.77 kg weight in the overweight and obese women who consumed CAE during this limited treatment period (Kazemipoor et al., 2013). In further examining the clinical results of that trial, this study examined the safety of CEA in overweight and obese women.
of the biochemical tests in the fasting condition. The blood chemistry and urine tests were examined by the ELITech diagnostics Kits (ELITech Group, 92800 Puteaux, France). The possible existence of adverse effects and the occurrence of changes in general health status of participants were monitored weekly by the physician and an investigator through physical examination during the period of the study.
Intervention feature. The eligible volunteers were randomly assigned to either the CAE or placebo groups in which they received bottled and coded CAE and placebo samples as a 14-day supply of 500 ml in sealed PET bottles. Subjects were instructed to drink either 30 ml of the CAE or placebo sample per day, 20 min before lunch, for 12 weeks. Participants, investigators, and data gatherers were all masked to the intervention procedures. The data analyser, who was not involved in the study, analysed the gathered data statistically, which made this study triple-blinded. Subjects were visited continuously at baseline (week 0), and every week up to the end of the 12 weeks of intervention by a physician, along with the investigators, to accomplish monitoring and data collection. Subjects were asked to record the occurrence of any side or adverse events related to the consumption of samples during the course of the study.
MATERIALS AND METHODS Study design. This study used a randomized, tripleblinded, placebo-controlled design involving 70 healthy women from Yazd, Iran with a body mass index (BMI) greater than 25 kg/m2 between the ages of 20 and 55 years, with a mean age of 37.1 years, a weight of 75.5 kg, and a BMI of 29.8. The study groups were randomized into a CAE group and a placebo group, with 35 participants in each group. The study was established to estimate the potential side-effects of the CAE compared with placebo. The protocol was approved by the Medical Ethics Committee of the University of Malaya Medical Centre (UMMC) with the protocol number 925/15, and the Protocol ID: NCT01833377 was approved by the clinicaltrial.gov protocol registration system. All of the subjects were asked to sign the informed consent form in consultation with their personal physician or healthcare provider. Pregnant or breast-feeding women, and subjects who were suffering from any severe health problem, including hormonal, cardiovascular, renal and hepatic disorders, those using alcohol, cigarettes, or any medication, or having an allergy to the CAE or the placebo products, were excluded from the trial.
Clinical and para-clinical valuations. Assessments, including heart rate, systolic and diastolic blood pressure, 25-item chemistry blood test, and urine specific gravity, were measured at baseline, and at the end of the 12-week intervention period. Cardiovascular measurements were performed by a physician using a calibrated mercury sphygmomanometer, and subjects were examined in a resting condition. Systolic and diastolic blood pressure was defined according to phase I and phase V Korotkoff sounds, respectively. Subjects were asked to refer to the reference laboratory of Shahid Sadoughi Hospital in Yazd, Iran for conduct Copyright © 2014 John Wiley & Sons, Ltd.
Test materials. The CAE product (0.1 w/v) was obtained through steam distillation of caraway seeds provided by the Baharan factory, in the Province of Yazd, Iran (Health Ministry license number 35/10500 and Industrial Ministry license number 28/1232). To profile the phytochemical constituents of the CAE, the samples were analysed by gas chromatography–mass spectrometry (GC–MS) using a flame ionization detector and then extracted by HS-SPME with subsequent hexane extraction (Kazemipoor et al., 2013). For the preparation of the placebo sample, the investigators provided the edible caraway essence produced by the Givaudan Flavours Company (Kempthal, Switzerland) and dissolved the essence (1 g) in drinking water (1 l) to achieve 1% g/l. The colour and flavour of the placebo thus prepared were indistinguishable from the CAE. Measuring bottles were given to participants, and they were requested to take 30 ml of either the placebo or the CAE and dissolve it in an equal amount of water using the measuring bottles. Brochures with written instructions were given to the participants before starting the intervention.
Statistical analysis. All statistical analyses were performed using SPSS software version 18.0.0 (SPSS Inc., Chicago, IL, USA). For removing outliers and for standardization of all outcome measures, Z-scores and the normal distribution (Kolmogorov–Smirnov) test were applied. A change from baseline to the end of the study was attained for each subject for each variable. Comparisons were made between the CAE and the placebo group, and also within each treatment group, during the treatment period. Those variables, which were either significantly increased or decreased from baseline compared with placebo, or were outside (above or below) the normal reference Phytother. Res. (2014)
CLINICAL TRIAL ON SAFETY AND BIOCHEMICAL EFFICACY OF CARUM CARVI
range, could reveal a negative or positive effect. In order to identify the significant differences in values between the two treatment groups, Student’s t test was used with a confidence interval of 99%. Also, the paired t test was applied to inspect the mean differences within each treatment group during the 12-week study period. All values are stated as mean ± standard deviation (SD). Differences with a P < 0.01 were considered to be clinically significant, and equal variances were assumed (Table 1).
RESULTS Of the 70 participants who were originally enrolled in the study, a total of 60 subjects completed the 12 weeks of treatment with the CAE or placebo. No adverse events were reported by any of the participants during the 12 weeks of CAE intervention. Table 1 shows the
baseline and concluding clinical and para-clinical variables, including heart rate, systolic and diastolic blood pressure, urine specific gravity, and 25-item blood test measurements for the two groups. No clinically significant effects from baseline were observed in the general health status between the placebo and the CAE groups. Also, no statistically noticeable effects were observed in the heart, liver, and kidney functions between the groups. However, after the 12-week trial, remarkable changes in red blood cell (RBC) and platelet distribution width (PDW) levels were observed between the CAE and placebo groups. The level of RBC in the CAE group was significantly increased, while the PDW was decreased in the CE group as compared to the placebo group. The phytochemicals present in the CAE, as detected by GC–MS, were the known volatile compounds shown in Fig. 1, based on the determination of these constituents in CAE (Kazemipoor et al., 2013).
Table 1. Measured variables (mean ± SD) at baseline and after intervention period Week 0 Variables
Reference range
Blood serum assessments Blood glucose 70–110 Liver function test Aspartate aminotransferase 5–40 Alanine aminotransferase 5–40 Alkaline phosphatase 64–306 Bilirubin, direct
Preliminary Safety Evaluation and Biochemical Efficacy of a Carum carvi Extract: Results from a Randomized, Triple-Blind, and Placebo-Controlled Clinical Trial Mahnaz Kazemipoor,1* Che Wan Jasimah Bt Wan Mohamed Radzi,1 Majid Hajifaraji2 and Geoffrey A. Cordell3 1
Department of Science and Technology Studies, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia National Nutrition and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran 1981619573, Iran 3 Natural Products Inc., Evanston, IL 60203, USA 2
Carum carvi L. (Apiaceae) is known as caraway, and its derivatives find wide medicinal use for health purposes, including for gastrointestinal problems and obesity. Since there is inconsistency among the reports on the safety of this plant in humans, this research was aimed at assessing the safety of a characterized caraway aqueous extract (CAE) in a randomized, triple-blind, placebo-controlled study. Seventy, overweight and obese, healthy women were randomly assigned into placebo (n = 35) and plant extract (n = 35) groups. Participants received either 30 ml/day of CAE or placebo. Subjects were examined at baseline and after 12 weeks for changes in heart rate, blood pressure, urine test, 25-item blood chemistries, and general health status. No significant changes of blood pressure, heart rate, urine specific gravity, and serum blood tests were observed between the two groups before and after treatment. However, in the complete blood count test, red blood cell levels were significantly (p < 0.01) increased, and platelet distribution width was significantly decreased after the dietary CAE treatment, as compared with placebo. No negative changes were observed in the general health status of the two groups. This preliminary study suggests that the oral intake of CAE appears to be without any adverse effects at a dosage of 30 ml daily for a period of 12 weeks. Copyright © 2014 John Wiley & Sons, Ltd. Keywords: Carum carvi; caraway aqueous extract; volatile compounds; safety; obesity; phytotherapy.
INTRODUCTION Primary health care based on plant extracts, or isolated natural products, is a popular and sometimes the only treatment approach available to communities all over the world. Indeed, approximately 25% of modern prescription medicines are derived from plants (Farnsworth et al., 1985). Plant-based medications are frequently perceived as being a natural and harmless (safe) form of therapy. However, medicinal plants and their extracts contain numerous phytochemicals, including toxins of exceptional potency, which target a diverse array of human genomic sites. Consequently, their consumption might result in a range of unpleasant reactions, or cause interactions, synergistic or antagonistic, with other medications. Therefore, scientifically establishing the safety of the constituents in a particular preparation must be a primary consideration in the delivery of phytotherapeuticals (Cordell and Colvard 2012). It is important to acknowledge that the safety of a plant cannot be assumed based on historical usage, especially if a different plant part or extraction methodology is * Correspondence to: Mahnaz Kazemipoor, Department of Science and Technology Studies, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia. E-mail: [email protected]
Copyright © 2014 John Wiley & Sons, Ltd.
employed. In addition, there is significant evidence accumulating to show that the ingestion of some plantbased products causes side effects and adverse reactions (Calixto 2000; Ernst 1998; Kazemipoor et al., 2012). Thus, characterization of a plant preparation being biologically evaluated is critical for reproducibility. Caraway, Carum carvi L. (Apiaceae), is a common and ancient medicinal plant. It is recommended as being safe in the form of a spice, as an extract, or as an essential oil, or in combination with other phytochemicals, for the treatment of a range of health problems (Sadowska and Obidoska 2003; Westphal et al., 1996). In addition, a variety of in vitro and in vivo studies have examined a range of different biological and pharmacological activities and health benefits of caraway ingredients. Several animal and human studies have suggested the efficacy of caraway preparations in the treatment of a number of diseases, including gastrointestinal problems (Khayyal et al., 2001; Thompson Coon and Ernst 2002), hyperglycemia (Ene et al., 2007), cancer (Kamaleeswari et al., 2006; Mazaki et al., 2006), and obesity (Kazemipoor et al., 2013). A number of studies have also reported on the safety and tolerability of caraway, along with its hepatoprotective potential (Sadowska and Obidoska 2003; Samojlik et al., 2010; Westphal et al., 1996). Therefore, caraway, by having a promising safety profile, has been recommended as an encouraging ingredient for safe usage as a traditional Received 08 November 2013 Revised 21 February 2014 Accepted 25 February 2014
M. KAZEMIPOOR ET AL.
medicine, and in the pharmaceutical and food manufacturing industries (Johri 2011; Thompson Coon and Ernst 2002). On the other hand, there are also warnings of possible allergic reactions, especially for children below 2 years of age, when the purified volatile oil is consumed (Taheri et al., 2011). Such negative reports are rare, and no scientifically valid clinical trial supports the claims regarding the negative reactions of caraway extract (CE) in humans (Nicotra 2012). Because of the paucity of information, and the concerns regarding the safety and tolerability of CE in humans, a randomized, triple-blind, placebo-controlled clinical trial was conducted to examine the safety and tolerability of aqueous extract of this plant through its effects on blood, and para-clinical, and clinical parameters in a study group receiving a caraway aqueous extract (CAE) compared with a placebo (control) group, over a 12-week experimental period. The anti-obesity property of CAE has been reported in the recent clinical trial. The primary outcomes of this study showed a significant reduction of 1.9 ± 1.77 kg weight in the overweight and obese women who consumed CAE during this limited treatment period (Kazemipoor et al., 2013). In further examining the clinical results of that trial, this study examined the safety of CEA in overweight and obese women.
of the biochemical tests in the fasting condition. The blood chemistry and urine tests were examined by the ELITech diagnostics Kits (ELITech Group, 92800 Puteaux, France). The possible existence of adverse effects and the occurrence of changes in general health status of participants were monitored weekly by the physician and an investigator through physical examination during the period of the study.
Intervention feature. The eligible volunteers were randomly assigned to either the CAE or placebo groups in which they received bottled and coded CAE and placebo samples as a 14-day supply of 500 ml in sealed PET bottles. Subjects were instructed to drink either 30 ml of the CAE or placebo sample per day, 20 min before lunch, for 12 weeks. Participants, investigators, and data gatherers were all masked to the intervention procedures. The data analyser, who was not involved in the study, analysed the gathered data statistically, which made this study triple-blinded. Subjects were visited continuously at baseline (week 0), and every week up to the end of the 12 weeks of intervention by a physician, along with the investigators, to accomplish monitoring and data collection. Subjects were asked to record the occurrence of any side or adverse events related to the consumption of samples during the course of the study.
MATERIALS AND METHODS Study design. This study used a randomized, tripleblinded, placebo-controlled design involving 70 healthy women from Yazd, Iran with a body mass index (BMI) greater than 25 kg/m2 between the ages of 20 and 55 years, with a mean age of 37.1 years, a weight of 75.5 kg, and a BMI of 29.8. The study groups were randomized into a CAE group and a placebo group, with 35 participants in each group. The study was established to estimate the potential side-effects of the CAE compared with placebo. The protocol was approved by the Medical Ethics Committee of the University of Malaya Medical Centre (UMMC) with the protocol number 925/15, and the Protocol ID: NCT01833377 was approved by the clinicaltrial.gov protocol registration system. All of the subjects were asked to sign the informed consent form in consultation with their personal physician or healthcare provider. Pregnant or breast-feeding women, and subjects who were suffering from any severe health problem, including hormonal, cardiovascular, renal and hepatic disorders, those using alcohol, cigarettes, or any medication, or having an allergy to the CAE or the placebo products, were excluded from the trial.
Clinical and para-clinical valuations. Assessments, including heart rate, systolic and diastolic blood pressure, 25-item chemistry blood test, and urine specific gravity, were measured at baseline, and at the end of the 12-week intervention period. Cardiovascular measurements were performed by a physician using a calibrated mercury sphygmomanometer, and subjects were examined in a resting condition. Systolic and diastolic blood pressure was defined according to phase I and phase V Korotkoff sounds, respectively. Subjects were asked to refer to the reference laboratory of Shahid Sadoughi Hospital in Yazd, Iran for conduct Copyright © 2014 John Wiley & Sons, Ltd.
Test materials. The CAE product (0.1 w/v) was obtained through steam distillation of caraway seeds provided by the Baharan factory, in the Province of Yazd, Iran (Health Ministry license number 35/10500 and Industrial Ministry license number 28/1232). To profile the phytochemical constituents of the CAE, the samples were analysed by gas chromatography–mass spectrometry (GC–MS) using a flame ionization detector and then extracted by HS-SPME with subsequent hexane extraction (Kazemipoor et al., 2013). For the preparation of the placebo sample, the investigators provided the edible caraway essence produced by the Givaudan Flavours Company (Kempthal, Switzerland) and dissolved the essence (1 g) in drinking water (1 l) to achieve 1% g/l. The colour and flavour of the placebo thus prepared were indistinguishable from the CAE. Measuring bottles were given to participants, and they were requested to take 30 ml of either the placebo or the CAE and dissolve it in an equal amount of water using the measuring bottles. Brochures with written instructions were given to the participants before starting the intervention.
Statistical analysis. All statistical analyses were performed using SPSS software version 18.0.0 (SPSS Inc., Chicago, IL, USA). For removing outliers and for standardization of all outcome measures, Z-scores and the normal distribution (Kolmogorov–Smirnov) test were applied. A change from baseline to the end of the study was attained for each subject for each variable. Comparisons were made between the CAE and the placebo group, and also within each treatment group, during the treatment period. Those variables, which were either significantly increased or decreased from baseline compared with placebo, or were outside (above or below) the normal reference Phytother. Res. (2014)
CLINICAL TRIAL ON SAFETY AND BIOCHEMICAL EFFICACY OF CARUM CARVI
range, could reveal a negative or positive effect. In order to identify the significant differences in values between the two treatment groups, Student’s t test was used with a confidence interval of 99%. Also, the paired t test was applied to inspect the mean differences within each treatment group during the 12-week study period. All values are stated as mean ± standard deviation (SD). Differences with a P < 0.01 were considered to be clinically significant, and equal variances were assumed (Table 1).
RESULTS Of the 70 participants who were originally enrolled in the study, a total of 60 subjects completed the 12 weeks of treatment with the CAE or placebo. No adverse events were reported by any of the participants during the 12 weeks of CAE intervention. Table 1 shows the
baseline and concluding clinical and para-clinical variables, including heart rate, systolic and diastolic blood pressure, urine specific gravity, and 25-item blood test measurements for the two groups. No clinically significant effects from baseline were observed in the general health status between the placebo and the CAE groups. Also, no statistically noticeable effects were observed in the heart, liver, and kidney functions between the groups. However, after the 12-week trial, remarkable changes in red blood cell (RBC) and platelet distribution width (PDW) levels were observed between the CAE and placebo groups. The level of RBC in the CAE group was significantly increased, while the PDW was decreased in the CE group as compared to the placebo group. The phytochemicals present in the CAE, as detected by GC–MS, were the known volatile compounds shown in Fig. 1, based on the determination of these constituents in CAE (Kazemipoor et al., 2013).
Table 1. Measured variables (mean ± SD) at baseline and after intervention period Week 0 Variables
Reference range
Blood serum assessments Blood glucose 70–110 Liver function test Aspartate aminotransferase 5–40 Alanine aminotransferase 5–40 Alkaline phosphatase 64–306 Bilirubin, direct
