Effects of three different doses of a fruit extract of Terminalia chebula on metabolic components of metabolic syndrome,in a rat model

There is documented evidence of the use of Terminalia chebula for various ailments in the Ayurvedic literature. The extract has been shown to possess glucose lowering activity and to improve insulin sensitivity in animal models of type 2 diabetes mellitus. The present study was carried out to study the dose response relationship of this extract in a rat model of metabolic syndrome. Six groups of rats were fed a high fructose diet (HFD) for a period of 20 days to induce metabolic syndrome. Three doses of fruit extract of T. chebula 50, 100 and 200 mg/kg were administered orally and pioglitazone 2.7 mg/kg was used as a positive control. Blood samples were collected at days 0, 20 and 40 from the tail vein. Systolic blood pressure (SBP) was measured using the tail cuff method and an oral glucose tolerance test (OGTT) was done on the day of blood collection. Administration of HFD for 20 days significantly increased fasting blood glucose (FBG), SBP and the area under the curve of OGTT. On day 40 the FBG in the 50, 100 and 200 mg/kg group was 97.33 ± 5.82 (NS), 86.83 ± 5.08 (p = 0.038) and 85.67 ± 6.74 (p = 0.15), respectively. These results show that the fruit extract of T. chebula exerts a significant and dose‐dependent glucose lowering effect in the rat model of metabolic syndrome. Copyright © 2009 John Wiley & Sons, Ltd.     

Acute and Sub‐Acute Oral Toxicity Assessment of the Hydroalcoholic Extract of Withania somnifera Roots in Wistar Rats

Withania somnifera is a widely used medicinal plant for several disorders. Toxicity studies on Withania somnifera are not available. Acute and sub‐acute oral toxicities of Withania somnifera root extract in Wistar rats were evaluated in the present study. In the acute toxicity study, WSR extract was administered to five rats at 2000 mg/kg, once orally and were observed for 14 days. No toxic signs/mortality were observed. In the sub‐acute study, WSR extract was administered once daily for 28 days to rats at 500, 1000 and 2000 mg/kg, orally. No toxic signs/mortality were observed. There were no significant changes (P < 0.05) in the body weights, organ weights and haemato‐biochemical parameters in any of the dose levels. No treatment related gross/histopathological lesions were observed. The present investigation demonstrated that the no observed adverse effect level was 2000 mg/kg body weight per day of hydroalcoholic extract of W. somnifera in rats and hence may be considered as non‐toxic. Copyright © 2012 John Wiley & Sons, Ltd.     

Bitter melon fruit extract has a hypoglycemic effect and reduces hepatic lipid accumulation in ob/ob mice

Bitter melon (Momordica charantia L.) is a vegetable and has been used as traditional medicine. Recently, we reported that bitter melon fruit extracts and its ethyl acetate (EtOAc)‐soluble fraction markedly suppressed the expression of proinflammatory genes, including the inducible nitric oxide synthase gene. However, it is unclear whether bitter melon exhibits antidiabetic effects. In this study, we showed that cucurbitacin B, a cucurbitane‐type triterpenoid, was present in an EtOAc‐soluble fraction and suppressed nitric oxide production in hepatocytes. When the EtOAc‐soluble fraction was administered for 7 days to ob/ob mice, a type 2 diabetes mellitus model, the mice fed with this fraction exhibited a significant decrease in body weight and blood glucose concentrations compared with the mice fed without the fraction. The administration of the fraction resulted in significant increases in serum insulin concentrations and the levels of both insulin receptor mRNA and protein in the ob/ob mouse liver. The EtOAc‐soluble fraction decreased the interleukin‐1β mRNA expression, as well as hepatic lipid accumulation in hepatocytes. Taken together, these results indicate that administration of an EtOAc‐soluble fraction improved hyperglycemia and hepatic steatosis, suggesting that this fraction may be responsible for both the antidiabetic and anti‐inflammatory effects of bitter melon fruit.     

Anxiolytic activity of a supercritical carbon dioxide extract of Souroubea sympetala (Marcgraviaceae)

The purpose of this work was to develop an extraction technique to yield a betulinic acid‐(BA) enriched extract of the traditional anti‐anxiety plant Souroubea sympetala Gilg (Marcgraviaceae). Five extraction techniques were compared: supercritical carbon dioxide extraction (SCE), conventional solvent extraction with ethyl acetate (EtOAc), accelerated solvent extraction (ASE), ultrasonic assisted extraction (UAE) and soxhlet extraction (Sox). The EtOAc and SCE extraction methods resulted in BA‐enriched extracts, with BA concentrations of 6.78 ± 0.2 and 5.54 ± 0.2 mg/g extract, respectively, as determined by HPLC‐APCI‐MS. The bioactivity of the BA‐enriched extracts was compared in the elevated plus maze (EPM), a validated rodent anxiety behaviour assay. Rats orally administered a 75 mg/kg dose of SCE extract exhibited anxiolysis as compared with vehicle controls, with a 50% increase in the percent time spent in the open arms, a 73% increase in unprotected head dips and a 42% decrease in percent time spent in the closed arms. No significant differences were observed between the SCE and EtOAc extracts for these measures, but the animals dosed with SCE extract had significantly more unprotected head dips than those dosed with the EtOAc extract. The SCE extract demonstrated a dose‐response in the EPM, with a trend toward decreased anxiety at 25 mg/kg, and significant anxiolysis was only observed at 75 mg/kg dose. This study demonstrates that SCE can be used to generate a betulinic acid‐enriched extract with significant anxiolysis in vivo. Further, the study provides a scientific basis for the ethnobotanical use of this traditional medicine and a promising lead for a natural health product to treat anxiety. Copyright © 2010 John Wiley & Sons, Ltd.     

诃子的研究进展及质量标志物的预测

诃子是我国传统中药材,在云南、广东、广西、西藏等地均有分布,诃子在我国中医临床用药广泛,在蒙药、藏药中占有非常重要的地位。诃子化学成分丰富多样,主要包括酚酸类、鞣质类、三萜类、脂肪族类、黄酮类、挥发油、氨基酸类、微量元素、碳水化合物等。现代药理学研究表明,诃子提取物具有抗氧化、抗癌抗肿瘤、解毒、抗菌、强心、抗炎、免疫调节、抗微生物、促进支气管平滑肌收缩等多种药理活性。通过查阅文献,从本草考证、化学成分、药理作用等方面对诃子研究进展进行阐述,根据质量标志物的核心理念,从植物亲缘学及化学成分特有性、传统功效、药性、药动学、新临床用途和化学成分可测性等方面对诃子质量标志物预测分析,为诃子质量评价研究提供参考。     

New Activities for Isolated Compounds from Convolvulus austro‐aegyptiacus as Anti‐ulcerogenic,Anti‐Helicobacter pylori and Their Mimic Synthesis Using Bio‐guided Fractionation

Bio‐guided fractionation of the total alcoholic extract of Convolvulus austro‐aegyptiacus was screened for its anti‐ulcerogenic activity, using an absolute‐ethanol‐induced ulcer model at 500 and 1000 mg/kg doses. Two compounds were isolated from the butanol extract of C. austro‐aegyptiacus and identified by ¹H and ¹³C nuclear magnetic resonance as scopoletin and scopolin. The isolated compounds (50 mg/kg) showed a remarkable anti‐ulcerogenic activity because they exhibited control‐ulcer protection by 16.7% and 90.8%, respectively. The acute toxicity study showed that the extract is highly safe; the median lethal dose (LD₅₀₎ was more than 4000 mg/kg. Moreover, the obtained results were confirmed by the sub‐chronic toxicity because the rats that have been administered 1000 mg/kg of the extract for 15 consecutive days showed no alteration in the liver and kidney functions. Copyright © 2015 John Wiley & Sons, Ltd.     

Hypoglycaemic activity of Geranium core-core,Oxalis rosea and Plantago major extract in rats

The hypoglycaemic activity of ‘Core-core’ (Geranium core-core, Geraniaceae), ‘Culle’ (Oxalis rosea, Oxalidaceae) and ‘Llantén’ (Plantago major, Plantaginaceae) crude extracts was assessed in normoglycaemic rats. Furthermore, the hypoglycaemic activity of Core-core extract was evaluated in alloxan-diabetic rats. A single oral dose of 500 mg/kg Core-core extract significantly reduced glycaemia in normal rats under glucose tolerance test conditions (p < 0.01), while Culle and Llantén were devoid of activity. The effect was lower than a single oral dose of 100 mg/kg tolbutamide. After 7 days oral treatment at 250 mg extract/kg body weight, Core-core significantly reduced glycaemia (p<0.01) in normal rats under oral glucose tolerance conditions. In alloxan-diabetic rats, a single oral dose of 500 mg/kg and chronic treatment at 250 mg/kg Core-core extract significantly reduced glycaemia in glucose tolerance test conditions at p < 0.05 and p < 0.01, respectively. During the acute oral toxicity study, animals treated with Core-core extract exhibited no symptoms of drug-induced toxicity with doses up to 5 g/kg.     

诃子基原物种及其混伪品的形态鉴别与分子鉴定

目的 建立能够准确鉴别诃子、绒毛诃子及其混伪品的分子鉴定方法。方法 对诃子、绒毛诃子及其混伪品的新鲜果实进行烘干,观察其干燥前后的形态;提取样品DNA,采用DNA条形码内转录间隔区2（ITS2）序列和psbA-trnH序列进行聚合酶链式反应扩增并测序,采用DANMAN 7、MAGE 6软件对测序结果进行序列比对,计算Kimura 2-paramete遗传距离,并构建邻接法系统发育树。结果 形态观察发现,诃子、绒毛诃子果实干燥前后与混伪品有较大的差异,可以通过形态差异进行鉴别;DNA条形码序列表明,诃子和绒毛诃子ITS2序列基本一致,仅发现4个单核苷酸多态性位点,但不能由此对两者进行区分;诃子和绒毛诃子的psbA-trnH序列存在2处明显差异,可对两者进行准确区分;绒毛诃子中存在2种类型的单倍型,其明显差异在于是否在psbA-trnH序列上存在1段16 bp的串联重复序列;混伪品与诃子、绒毛诃子之间具有较大的psbA-trnH序列差异,可直接在美国国家生物技术信息中心比对进行区分;对市场上流通的诃子炮制品进行鉴定发现,其多为2种单倍型绒毛诃子,且存在毛诃子混伪的情况。结论 利用psbA-trnH序列可准确鉴别诃子、绒毛诃子及其混伪品,发现绒毛诃子中存在2种类型的单倍型。     

壮药土甘草水提物及醇提物毒理学研究

目的 观察土甘草水提物和醇提物对小鼠灌胃给药的急性毒性.方法 以土甘草水提物1.57 g/ml,醇提物2.40 g/ml,最大剂量40 ml/kg分别对小鼠灌胃给药,观察其急性毒性.结果 给药后,小鼠均蜷卧少动,24 h后此症状消失.观察7 d,小鼠的行为、进食、皮毛、眼和粘膜、呼吸、四肢活动和体重均无异常,未出现其它毒性反应.土甘草水提物对小鼠灌胃给药的最大耐受量为62.8 g生药/kg;醇提物对小鼠灌胃给药的最大耐受量为96.0 g生药/kg.结论 土甘草水提物对小鼠灌胃给药的最大耐受量为62.8 g生药/kg;醇提物对小鼠灌胃给药的最大耐受量为96.0 g生药/kg.未出现其它毒性反应.     

Preventive effects of chebulic acid isolated from Terminalia chebula on advanced glycation endproduct-induced endothelial cell dysfunction

Aim of the study

The aqueous extract of Terminalia chebular fruits was reported to have anti-hyperglycemia and anti-diabetic complication effects. The present study therefore investigated the protective mechanism of chebulic acid, a phenolcarboxylic acid compound isolated from the ripe fruits of Terminalia chebula against advanced glycation endproducts (AGEs)-induced endothelial cell dysfunction.

Materials and methods

To investigate the protective mechanism of chebulic acid against vascular endothelial dysfunction human umbilical vein endothelial cells (HUVEC) were treated with chebulic acid in the presence/absence of glyceraldehyde-related AGEs (glycer-AGEs).

Results

HUVEC incubated with 100 μg/ml of glycer-AGEs had significantly enhanced reactive oxygen species formation, whereas the treatment of chebulic acid dose-dependently reduced glycer-AGE-induced formation to 108.2 ± 1.9% for 25 μM versus 137.8 ± 1.1% for glycer-AGEs treated alone. The transendothelial electrical resistance (TER) value of the glycer-AGEs group was dramatically decreased to 76.9 ± 2.2% compared to the control, whereas chebulic acid treatment prevented glycer-AGE-induced TER change with a value of 91.3 ± 5.3%. The incubation of confluent HUVEC with 100 μg/ml of glycer-AGEs for 24 h remarkably increased the adhesion of human monocytic THP-1 cells compared to non-stimulated HUVEC. These increases in HUVEC adhesiveness were dose-dependently reduced by chebulic acid.

Conclusions

The present study shows the effects of chebulic acid against the progression of AGE-induced endothelial cell dysfunction suggesting that this compound may constitute a promising intervention agent against diabetic vascular complications.     

Toxicity studies on dermal application of plant extract of Dodonaea viscosa used in Ethiopian traditional medicine

Despite advances in the understanding of the medicinal properties of many herbs, the consumer today is confronted with the lack of or misinformation concerning the safety of these herbs that rivals the heyday of the patent medicine era. In the present study, Dodonaea viscosa (Sapindaceae), a medicinal plant commonly used for skin diseases in Ethiopia was subjected to a systematic dermatotoxicity study. To this effect, the dermatotoxicity of an 80% methanol extract of the leaf was investigated in animals following standard procedures for irritation, sensitization, acute toxicity and repeated toxicity tests. The skin irritation test in rabbits showed the extract to be a slight or negligibly slight irritant, with a primary irritation index of 0.45. A sensitization test in mice by the mouse ear swelling test method revealed the extract to be a non‐sensitizer in the dose range 12–30 mg/mL. The percent responder was zero. The acute and repeated dermal toxicity tests on rats did not show any overt sign of toxicity. The findings of this study collectively indicate that dermal application of D. viscosa is not associated with any toxicologically relevant effects and the data could provide satisfactory preclinical evidence of safety to launch a clinical trial on a standardized formulation of the plant extracts. Copyright © 2009 John Wiley & Sons, Ltd.     

Hypoglycaemic activity of Hexachlamys edulis (‘Yvahai’) extract in rats

The hypoglycaemic activity of the extract of the crude drug ‘Yvahai’ (Hexachlamys edulis, Myrtaceae) was assessed on normoglycaemic and alloxan-diabetic rats. After 7 days of oral treatment at 100 mg extract/kg body weight, Yvahai significantly reduced glycaemia in normal (p<0.02) and diabetic (p<0.05) rats during an oral glucose tolerance test. The maximum effect was observed between 1.5 and 2.5 h after glucose administration in normoglycaemic rats, and at 1.0 h in diabetic animals. The extract, however, did not have a statistically significant effect on the basal glycaemia of untreated compared with treated rats. A single oral dose of 500 mg extract/kg administered to normoglycaemic rats 1 h before glucose, elicited a significant reduction (p < 0.02) in the percent increase in glycaemia compared with vehicle-treated animals. The effect was comparable to a single oral dose of 100 mg/kg tolbutamide. During the oral toxicity study, animals exhibited no symptoms of drug-induced toxicity with doses up to 5 g/kg.     

诃子醇提物对动物胃肠运动和血清胃动素含量的影响

目的: 研究诃子醇提物对动物胃肠运动和血清胃动素含量的影响。 方法: 将实验动物随机分为空白对照组、吗丁啉（小鼠0.005 g·kg^-1,大鼠0.003 g·kg^-1）组,诃子提取物高、中、低剂量组（小鼠3.5,1.75,0.875 g·kg^-1,大鼠2.4,1.2,0.6 g·kg^-1）,按10 mL·kg^-1给药,采用小鼠在体胃肠运动实验、放免法检测大鼠血清胃动素含量和家兔离体肠平滑肌运动实验,观察诃子提取物对正常小鼠胃排空、小肠推进运动和大鼠血清胃动素含量以及家兔离体肠平滑肌收缩的影响。 结果: 诃子提取物高、中剂量对正常小鼠胃排空和小肠推进运动有显著抑制作用,可以降低大鼠血清胃动素的含量,对家兔离体肠平滑肌收缩有显著抑制作用,对氯化乙酰胆碱引起的肠平滑肌兴奋有显著拮抗作用（P<0.05或P<0.01）。 结论: 诃子醇提物对动物胃肠运动有抑制作用,其作用途径可能与M胆碱受体有关。     

Toxic effects of oral administration of extracts of dried calyx of Hibiscus sabdariffa Linn. (Malvaceae)

The effects of a 90‐day oral administration of water and alcohol extracts of dried calyx of Hibiscus sabdariffa were evaluated in albino rats. Haematological, biochemical and histopathological changes were monitored every 30 days. The death of the animals was preceded by a severe loss in weight, accompanied with diarrhoea in animals on the 2000 mg/kg dose. There was an increase in food intake (g) per kg body weight per day in the aqueous (A) and ethanol (E) 300 mg/kg extract groups. Significant reductions in the erythrocyte count with no difference in total leucocyte count were observed. The activity of aspartate aminotransferase (AST) was enhanced by the administration of aqueous and 50% ethanol extract with a significant increase in its level at higher doses (p < 0.05). Alanine aminotransferase (ALT) and creatinine levels were significantly affected by all the extracts at the different dose levels. However, aqueous extracts exhibited a significant increase in creatinine levels (p < 0.05) at higher doses. The cholesterol levels were generally not significantly affected by the extracts. No significant histopathological changes were observed, although there was a significant reduction in the weight of the spleen of the animals administered with ethanol and water extracts when compared with the control (p < 0.01). Other organs were of the same relative weight. Copyright © 2008 John Wiley & Sons, Ltd.     

Acute and subchronic oral toxicity studies of Nelumbo nucifera stamens extract in rats

Ethnopharmacological relevance

Since the use of Nelumbo nucifera stamens in herbal medicines as well as in cosmetic products are highly prevalent in Thailand and increasing worldwide, acute and subchronic toxicity studies to confirm the safe use of Nelumbo nucifera stamens are warranted.

Aim of the study

Acute and subchronic oral toxicity studies of Nelumbo nucifera stamens extract in rats were performed in the present study in order to evaluate its safety.

Materials and methods

In acute toxicity study, Nelumbo nucifera stamens extract was administered by oral gavage to Sprague-Dawley rats (5 males and 5 females) at a dose of 5000 mg/kg. In subchronic toxicity study, the extract at doses of 50, 100, and 200 mg/kg/day were given orally to groups of rats (6 rats/dose/sex) for 90 consecutive days.

Results

The extract at a dose of 5000 mg/kg produced no treatment-related signs of toxicity or mortality in any of the animals tested during 14 days of the study. In the repeated dose 90-day oral toxicity study, there was no significant difference in body weight between the control and all treatment groups with the exception of the body weight of the female group treated with 200 mg/kg/day of the extract which was statistically significantly less than that of its control counterpart on day 90 but the percent weight changes of both groups were almost similar. Some statistically significant differences in hematological and biochemical parameters as well as in some internal organ weights of both male and female rats treated with the extract at the highest dose were observed. However, no abnormality of internal organs was observed in both gross and histopathological examinations.

Conclusions

These results suggest that the oral lethal dose of Nelumbo nucifera stamens extract for male and female rats is in excess of 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is considered to be 200 mg/kg/day.     

Acute and subacute toxicity study of the ethanol extract from Lonicera japonica Thunb

The ethanol extract from the leaves of Lonicera japonica Thunb. was evaluated for acute and subacute toxicity. The single oral dose of the ethanol extract at 5,000 mg/kg did not produce mortality or significant changes in the general behaviour and gross appearance of the internal organs of rats. In subacute toxicity study, the ethanol extract was administered orally at a dose of 1,000 mg/kg/day for a period of 14 days. The satellite group was treated with the ethanol extract at the same dose and the same period and kept for another 14 days after treatment. There were no significant differences in the body and organ weights between the control and the treated group of both sexes. Hematological analysis and clinical blood chemistry revealed no toxicity effects of the extract. Pathologically, neither gross abnormalities nor histopathological changes were observed.     

β-glucuronidase inhibition and diuretic activity of Fabiana imbricata R. & P. (Solanaceae)

The hydroalcoholic extract of Fabiana imbricata inhibited the enzyme β-glucuronidase (β-gluc) in vitro. Bioassay-guided isolation led to scopoletin as the main active constituent of F. imbricata. Scopoletin was a noncompetitive inhibitor of β-D-glucuronidase with a K_i value of 4 × 10^?5 M. A single oral dose of 250 mg/kg body weight F. imbricata extract produced a significant increase (p<0.05) in the urine output of rats. The diuretic effect of the extract was weak in comparison with hydrochlorothiazide at 25 mg/kg. In the acute oral toxicity study in rats, ‘Pichi’ was shown to be a low toxicity crude drug at doses up to 5 g crude extract/kg body weight. At concentrations up to 0.50 mg/mL, the crude extract did not increase the number of chromosome aberrations in the in vitro human lymphocyte assay.     

药用拟层孔菌子实体提取物的抗肿瘤活性研究

目的:测定药用拟层孔菌子实体的石油醚粗提物、乙酸乙酯粗提物和甲醇粗提物的总三萜及总甾醇含量;研究3种粗提物及从乙酸乙酯粗提物中分离得到的三萜类单体化合物的体内抗肿瘤活性。探讨其抗肿瘤活性与总三萜和总甾醇含量的关系。方法:通过分光光度法测定3种粗提物的总三萜和总甾醇含量。通过H22荷瘤小鼠移植模型的体内抗肿瘤实验,观察该真菌子实体的石油醚提取物、乙酸乙酯提取物、甲醇提取物及三萜类单体化合物的抗肿瘤活性进行评价。结果:乙酸乙酯粗提物中总三萜含量和总甾醇含量最高,石油醚次之。从乙酸乙酯层分离得到5个单体化合物:去氢齿孔酮酸,3-酮基-去氢硫色多孔菌酸,去氢齿孔酸,阿里红酸A和阿里红酸C。在体内实验中,乙酸乙酯层抑瘤率效果最佳,当浓度达到1 000mg·kg~(-1)时抑瘤率为64.65%,与阳性药5-氟尿嘧啶(5-Fu)的抑瘤率(59.98%)接近,并且免疫器官指数均有一定的变化。单体化合物2(3-酮基-去氢硫色多孔菌酸)抑瘤率为75.13%,与阳性药物CTX(81.76%)抑瘤率接近,比阳性药5-Fu高。其余4种单体化合物也有一定作用效果。结论:乙酸乙酯提取物及这5种单体化合物能有效抑制肿瘤的生长,并且对机体的免疫力有较好的促进作用,该5种单体化合是药用拟层孔菌子实体的抗肿瘤活性成分,药用拟层孔菌的抗肿瘤活性成分可能是三萜类化合物。     

Cytochrome P450 Inhibition Assay for Standardized Extract of Terminalia chebula Retz.

The hydroalcoholic extract of fruit pulp of Terminalia chebula Retz. was standardized and evaluated for its safety through cytochrome P450 (CYP 450) inhibition assay. Standardization was performed through high performance thin layer chromatography (HPTLC) using gallic acid (GA) standard. Cytochrome P450‐CO complex microplate assay was performed using rat liver microsomes. The effect of standardized extract, its fraction and bioactive marker compound were comparatively evaluated for its effect on CYP P450 enzymes. The extract of fruit pulp was used for HPTLC, where the R_f value of the marker was found to be 0.43. The calibration plot was linear in the range of 2–14 µg of GA and correlation co‐efficient of 0.99965. The mean quantity of GA was found to be 2.5% w/w. The CYP P450 concentration of the rat liver microsome sample used in the study was found to be 0.417 nmol/mg protein. The in vitro effect of various concentrations of extracts and fractions showed a linear concentration‐dependent inhibition of cytochrome P450 up to 60 µL. The study showed more inhibition of fraction when compared to the extract and GA. Still, the inhibition showed by fraction is less when compared with standard Ketoconazole. Thus, this study indicated the in vitro cytochrome P450 inhibition potential of T. Chebula.     

Cytotoxic activity of marine macro‐algae on Artemia salina (Brine shrimp)

A total of 22 ethanol extracts of seaweed species (13 brown, 6 green and 3 red) collected from the Karachi coast were investigated for brine shrimp cytotoxicity. Of all the species, only six namely Stoechospermum marginatum, Sargassum swartzii, S. binderi, Spatoglossum asperum, Stokeyia indica (brown) and Caulerpa racemosa (green) showed significant activity. n‐Hexane‐soluble fractions of the ethanol extract of S. marginatum and S. swartzii were found to be responsible for the activity, whereas the methanol‐soluble fractions of S. asperum and S. binderi were most active. The water extract of S. indica and C. racemosa exhibited the most prominent activity (LC₅₀ value below 70 µg/mL) when compared with the ethanol extracts and their fractions. Cytotoxic activity may be due to the compounds differing in polarity. Copyright© 1999 John Wiley & Sons, Ltd.