RESUMO
BACKGROUND: Psidium guajava L (Guava) belongs to the Myrtaceae family and has been claimed to possess several pharmacological properties including antidiabetic. OBJECTIVE: This study was designed to evaluate the anti-hyperglycemic activity of P guajava L leaves aqueous extract on neonatal streptozotocin-induced type 2 diabetic model rats. METHODS: Streptozotocin was induced (90 mg/kg) intraperitoneally to 48 h old Long Evans rat pups. After three months, 18 male type-2 diabetic model rats were confirmed by OGTT (FG > 7 mmol/L). Therefore, experimental rats were divided into three groups 2) Diabetic water control (10 ml/kg), 3) Gliclazide treated (20 mg/kg), and 4) Extract treated group (1.25g/kg)] Six normal female rats comprised group 1 [Non-diabetic water control (10 ml/kg)]. All rats were treated orally with their respective treatment for 28 consecutive days. Blood samples were collected on 0 days (by tail cut method) and the end day (by cardiac puncture) of the experiment. The anti-hyperglycemic activity was evaluated by measuring fasting glucose, serum insulin, lipid profile, hepatic glycogen content, and intestinal glucose absorption by standard methods. RESULTS: The serum glucose level of extract treated group was decreased by 16% as well as significantly (p<0.05) increased the serum insulin level (M±SD, 0 day vs 28thday; 0.319 ± 0.110 vs 0.600 ± 0.348, µg/L). Moreover, the extract-treated group also significantly (p<0.05) enhanced liver glycogen content and inhibited glucose absorption from the upper intestine. Besides, a significant (p < 0.05) reduction of LDL-cholesterol level was found in the extract-treated group (M±SD, 55 ± 33 vs 14 ± 9, mg/dl) compared with baseline values where other groups did not show any statistically remarkable changes. CONCLUSION: Current study concludes that P guajava leaves aqueous extract enhances insulin secretion from pancreatic beta-cells and promotes glycogen synthesis in the liver. The extract also inhibits glucose absorption from the upper intestine and improves dyslipidemia to some extent. Therefore, possesses the potential for drug development against T2DM.
RESUMO
A new phenylpropanoid glycoside, alpha-L-rhamnopyranosyl-(1 --> 3)-O-alpha-L-rhamnopyranosyl-(1 --> 6)-1-O-caffeoyl-beta-D-glucopyranoside (1) along with two known phenylethanoid glycosides (2-3) has been isolated from the aerial parts of Leucas indica Linn. Their structures were deduced from the spectroscopic studies and compared with the literature values.
Assuntos
Glicosídeos/isolamento & purificação , Lamiaceae/química , Fenilpropionatos/isolamento & purificação , Bangladesh , Glicosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Fenilpropionatos/química , EstereoisomerismoRESUMO
A new phenylethanoid glycoside, 2-(3,4-dihydroxyphenyl)-ethyl-O-alpha-L-rhamnopyranosyl-(1 --> 3)-O-alpha-L-rhamnopyranosyl-(1 --> 6)-4-O-E-feruloyl-beta-D-glucopyranoside (3-O-methyl poliu-moside, 1) along with five known phenylethanoid glycosides (2-6) were isolated from the aerial parts of Leucas indica Linn. The structure of compound 1 has been elucidated on the basis of spectral data. Compounds 1-6 exhibited significant antioxidant activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assay method. These compounds were also found to be moderate inhibitors of xanthine oxidase (XO) enzyme.
Assuntos
Inibidores Enzimáticos/isolamento & purificação , Sequestradores de Radicais Livres/isolamento & purificação , Glicosídeos/isolamento & purificação , Lamiaceae/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Bangladesh , Compostos de Bifenilo/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Glicosídeos/química , Glicosídeos/farmacologia , Hidrazinas/metabolismo , Ressonância Magnética Nuclear Biomolecular , Rotação Ocular , Fenóis/química , Picratos , Extratos Vegetais/química , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/metabolismoRESUMO
Quinovic acid-3-O-alpha-L-rhamnopyranoside (1), quinovic acid-3-O-beta-D-fucopyranoside (2), quinovic acid-3-O-beta-D-glucopyranosyl (1 --> 4)-beta-D-fucopyranoside (3), methyl gallate (4) and ethyl gallate (5) were isolated from the ethyl acetate extract of Bridelia ndellensis barks by fractionation. Compounds 1-3 showed significant inhibitory activity against snake venom phosphodiesterase-I.
Assuntos
Euphorbiaceae/química , Glicosídeos/isolamento & purificação , Fosfodiesterase I/antagonistas & inibidores , Inibidores de Fosfodiesterase/isolamento & purificação , Triterpenos/isolamento & purificação , Glicosídeos/química , Glicosídeos/farmacologia , Conformação Molecular , Ressonância Magnética Nuclear Biomolecular , Fosfodiesterase I/metabolismo , Inibidores de Fosfodiesterase/química , Inibidores de Fosfodiesterase/farmacologia , Casca de Planta/química , Saponinas/química , Saponinas/isolamento & purificação , Saponinas/farmacologia , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Triterpenos/química , Triterpenos/farmacologiaRESUMO
Caesalpinia bonducella F., is a shrub widely distributed throughout the coastal region of India and is ethnically used by the tribal people of Andaman and Nicober Island as a remedy of symptoms of diabetes mellitus. This ethnic report prompted the detail investigation of hypoglycemic activity of Caesalpinia bonducella seeds, initially on physiological hyperglycemic model and then on type 1 and type 2 sub-acute diabetic animal models which has already been reported. Evaluation of different extracts from Caesalpinia bonducella in chronic type 2 diabetic model alongwith insulin secretagogue activity of five fractions isolated from the Caesalpinia bonducella seed kernel are presented in this paper. Both the aqueous and ethanolic extracts showed potent hypoglycemic activity in chronic type 2 diabetic model. Two fractions BM 169 and BM 170 B could increase secretion of insulin from isolated islets.
Assuntos
Caesalpinia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Animais , Doença Crônica , Diabetes Mellitus Tipo 2/sangue , Modelos Animais de Doenças , Feminino , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Masculino , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Long-Evans , SementesRESUMO
Three compounds namely, (7S,8R)-dihydrodehydrodiconiferyl alcohol-9'-O-beta-D-glucopyranoside (1), 10-hydroxy-4,7-megastigmadien-3-one-9-O-beta-D-glucopyranoside (2) and 9-hydroxy-4,7-megastigmadien-3-one-10-O-beta-D-glucopyranoside (3) were isolated from the methanol extract of Pterospermum semisagittatum. The structures of these compounds were elucidated by spectroscopic methods. While glycosides 2 and 3 appear to be new, this is the third report of isolation of compound 1 from any natural source.
Assuntos
Cicloexanonas/química , Glucosídeos/química , Lignanas/química , Malvaceae/química , Norisoprenoides/química , Cicloexanonas/isolamento & purificação , Glucosídeos/isolamento & purificação , Glicosídeos/química , Glicosídeos/isolamento & purificação , Lignanas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Metanol , Norisoprenoides/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Solventes , Espectrometria de Massas de Bombardeamento Rápido de ÁtomosRESUMO
The structure of the Vibrio fluvialis M-940 O-antigen polysaccharide has been investigated by sugar and methylation analyses, specific degradations, NMR spectroscopy, and mass spectrometry. It is proposed that it consists of a heptasaccharide unit having the following structure. alpha-L-Rhap-(1-->2)-alpha-L-Fucp-(1-->2)-alpha-D-Galp-(1--> 2)-alpha-L-Fucp- (1-->3)-beta-D-GlcpA-(1-->4)-alpha-L-Rhap-(1-->3)-beta-D-Glc pNAc-(1--> The heptasaccharide is most probably linked to the 3-position of an alpha-D-galactopyranosyl residue in the core.
Assuntos
Polissacarídeos Bacterianos/química , Vibrio , Configuração de Carboidratos , Sequência de Carboidratos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular , Oligossacarídeos/genética , Oligossacarídeos/isolamento & purificação , Polissacarídeos Bacterianos/isolamento & purificação , Espectrometria de Massas de Bombardeamento Rápido de ÁtomosRESUMO
The structure of the Vibrio mimicus W-26768 O-antigen polysaccharide has been investigated by sugar and methylation analyses, Smith degradation, and NMR spectroscopy. It is proposed that it is composed of chains of beta-(1-->4)-linked 3,6-dideoxy-3-[(R)-3-hydroxybutyramido]-D-glucopyranosyl residues (D-Qui(p)3NR), approximately 60% of which are substituted in the 2-position with 2-acetamido-2-deoxy-alpha-D-galactopyranosyl groups. The polysaccharide does not seem to be composed of oligosaccharide repeating units but has a less regular structure, schematically indicated below. [formula: see text]
Assuntos
Lipopolissacarídeos/química , Polissacarídeos Bacterianos/química , Vibrio/química , Configuração de Carboidratos , Sequência de Carboidratos , Diarreia/microbiologia , Humanos , Indicadores e Reagentes , Lipopolissacarídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Polissacarídeos Bacterianos/isolamento & purificação , Vibrio/isolamento & purificaçãoRESUMO
The structure of the Shigella boydii type 5 O-antigen polysaccharide has been investigated by sugar and methylation analyses, and specific degradations. It is proposed that it is composed of hexasaccharide repeating units with the following structure. The repeating unit also contains an O-acetyl group, linked to one of the primary positions. [formula: see text]
Assuntos
Polissacarídeos Bacterianos/química , Shigella boydii/química , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência MolecularRESUMO
Caesalpinia bonducella, widely distributed throughout the coastal region of India and used ethnically by the tribal people of India for controlling blood sugar was earlier reported by us to possess hypoglycemic activity in animal model. This prompted us to undertake a detail study with the aqueous and ethanolic extracts of the seeds of this plant in both type 1 and 2 diabetes mellitus in Long Evans rats. Significant blood sugar lowering effect (P < 0.05) of C. bonducella was observed in type 2 diabetic model. Special emphasis was given on the mechanistic study by gut absorption of glucose and liver glycogen.
Assuntos
Caesalpinia/química , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Relação Dose-Resposta a Droga , Feminino , Glicogênio/metabolismo , Hipoglicemiantes/uso terapêutico , Absorção Intestinal/efeitos dos fármacos , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Ratos , Ratos Long-EvansRESUMO
The soluble dietary fibre (SDF) fraction of Trigonella foenum graecum (Tf-sdf) has previously been shown to reduce postprandial elevation in blood glucose level of Type 2 model diabetic rats by delaying the digestion of sucrose. The Tf-sdf has now been investigated for its chronic effect on serum fructosamine, insulin and lipid levels, and on platelet aggregation in Type 2 diabetic rats. Tf-sdf was administered orally twice daily at a dose of 0.5 g kg(-1) for 28 days. It lowered the serum fructosamine level (P<0.05) with no significant change in the insulin level as compared with the control. Atherogenic lipids, i.e. triglycerides, cholesterol and LDL-cholesterol were found to decrease significantly in Tf-sdf fed rats (P<0.01). HDL-cholesterol showed an opposite trend (P=0.024), but serum non-esterified fatty acid (NEFA) values paralleled the atherogenic lipids (P=0.001). No significant effect on platelet aggregation (%) was found although there was a tendency to lower the aggregation (P=0.069). It is concluded that Tf-sdf has a beneficial effect on dyslipidemia and has a tendency to inhibit platelet aggregation in Type 2 model diabetic rats.
Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fibras na Dieta/farmacologia , Fibras na Dieta/uso terapêutico , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Trigonella , Administração Oral , Animais , Esquema de Medicação , Frutosamina/sangue , Frutosamina/metabolismo , Índia , Insulina/sangue , Metabolismo dos Lipídeos , Lipídeos/sangue , Masculino , Agregação Plaquetária/efeitos dos fármacos , Ratos , Ratos Long-Evans , Sementes , Fatores de TempoRESUMO
Three novel flavonoid glycosides, 5,6-dimethyoxy-3',4''-dioxymethylene-7-O-(6''-beta-D-glucopyranosyl-beta-D-glucopyranosyl) flavanone (1), 5,4'-dihydroxy-3-O-alpha-L-rhamnopyranosyl-6-C-glucopyranosyl-7-O-(6''-para-coumaroyl-beta-D-glucopyranosyl) flavone (2) and 5,4'-dihydroxy-3-O-(2'''''-beta-glucopyranosyl-alpha-L-rhamnopyranosyl)-6-C-glucopyranosyl-7-O-(6''-para-coumaroyl-beta-D-glucopyranosyl) flavone (3) were isolated from the 1-butanol soluble fraction of the bulbs of the plant Urginea indica (Indian squill). The structures of the compounds were elucidated on the basis of spectral analysis, including homo- and heteronuclear correlation NMR experiments (COSY, NOESY, HSQC and HMBC) and mass spectra.
Assuntos
Drimia/química , Flavonoides/química , Glicosídeos/química , Raízes de Plantas/química , Espectroscopia de Ressonância Magnética , Estrutura MolecularRESUMO
The present study is aimed to assess persistent organic halogenated pollutants in humans living in Bangladesh. The results are compared to other similar studies in the region and globally. Human blood plasma were collected from groups of men and women with different occupations, i.e. being students, garment industry workers, employees at the Power Development Board (PDB), all groups in Dhaka, fishermen and fishermen wife's from Dhaka and another group from Barisal district. The plasma was analysed for hexachlorobenzene (HCB), the hexachlorocyclohexane isomers, alpha-HCH, beta-HCH, gamma-HCH and delta-HCH, the DDT group of chemicals, chlordane compounds, trans-chlordane, cis-chlordane, oxychlordane, trans-nonachlor, trans-heptachlorepoxide, methoxychlor and mirex. The most abundant contaminant, in all groups studied, p,p'-DDE is dominating, with p,p'-DDT/Sigma DDT ratios indicating recent and ongoing DDT exposure. Among the other pesticides analysed beta-HCH is the most abundant indicating the use of technical HCH products instead of Lindane (gamma-HCH). While the Sigma DDT is present in the low ppm range the beta-HCH is detected in up to approx. 400 ppb, lipid basis. The beta-HCH is most abundant in the groups of students. In contrast to the pesticides analysed very low concentrations of polychlorinated biphenyls (PCB) are present in all study groups, with e.g. CB-153 in the range of 5-30 ng g(-1) fat. The concentrations of the DDT group of chemical differ significantly between fishermen and fishermen's wives living and working in the Dhaka area versus those living and working in Barisal. Also, fishermen and their wives had significantly different concentrations of DDT compared to garment industry workers.
Assuntos
Anticonvulsivantes/sangue , Monitoramento Ambiental , Poluentes Ambientais/sangue , Hidrocarbonetos Halogenados/sangue , Inseticidas/sangue , Exposição Ocupacional/análise , Bangladesh , DDT , Diclorodifenil Dicloroetileno , Feminino , Hexaclorocicloexano , Humanos , Masculino , Ocupações , Bifenilos Policlorados , Medição de Risco , EstereoisomerismoRESUMO
The effects of Ficus racemosa Linn. fruit extract and fraction on fasting serum glucose levels of normal, type 1 and type 2 diabetic model rats are presented. The aqueous 80% EtOH extract and its water soluble fraction of F. racemosa fruit did not show any serum glucose lowering effect on non-diabetic and type 2 diabetic rats at the fasting condition, whereas the extract showed significant hypoglycaemic effect on the type 1 diabetic model rats. Both the extract and fraction were consistently active in both non-diabetic and types 1 and 2 diabetic model rats when fed simultaneously with glucose load. On the contrary, they were ineffective in lowering blood glucose levels when fed 30 min prior to glucose load. The 1-BuOH soluble part of the ethanol extract exhibited significant antioxidant activity in DPPH free radical scavenging assay. 3-O-(E)-Caffeoyl quinate (1) was isolated for the first time from this plant, which also showed significant antioxidant activity.
Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Ficus/química , Frutas/química , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Animais , Antioxidantes/isolamento & purificação , Glicemia/efeitos dos fármacos , Modelos Animais de Doenças , Hipoglicemiantes/isolamento & purificação , Espectroscopia de Ressonância Magnética , Masculino , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Long-EvansRESUMO
Six new diterpenoids were isolated from a CH(2)Cl(2)-MeOH extract of the bark of Suregada multiflora. The structures were established on the basis of one- and two-dimensional NMR and other spectroscopic studies and chemical derivatizations. Two compounds, suregadolides C (1) and D (2), were identified as new diterpene lactones of two antipodal series, containing a cyclopropane ring bridging C-3 and C-4 of the basic abietane skeleton. Suremulide A (3) was found to be a new abietene diterpene lactone. Bannaringaolide A (4), a diterpene lactone, based on a novel carbon skeleton with a seven-membered ring, possibly formed by the rearrangement of the exocyclic C-17 in ring C of an ent-pimarane framework, has also been isolated. A kaurane triol, suremulol A (5), and a kaurane diol, suremulol B (6), were also identified as new metabolites.
Assuntos
Abietanos/isolamento & purificação , Diterpenos/isolamento & purificação , Lactonas/isolamento & purificação , Plantas Medicinais/química , Suregada/química , Abietanos/química , Bangladesh , Diterpenos/química , Lactonas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Casca de Planta/químicaRESUMO
Vibrio mimicus strains W-26768 (stool isolate) and N-1301 (environmental isolate) and Vibrio fluvialis strains AA-18239 (stool isolate) and M-940 (environmental isolate) were studied for virulence properties and lipopolysaccharide composition. All four strains were hydrophobic, produced cytotoxin, adhered to HeLa cells and showed mannose-sensitive agglutination of guinea pig erythrocyte. The strains were negative for enterotoxin production and were mostly susceptible to the common antibiotics. The environmental and clinical isolates of both species were antigenically unrelated to each other. Lipopolysaccharide antigen analysis showed that O-antigen polysaccharides of two strains of V. fluvialis and two strains of V. mimicus differed with respect to the sugar components. Only LPS from V. mimicus W-26768 showed the presence of an unusual sugar, 3,6-dideoxy-3-acetamido-hexose. The sugar compositions of these V. fluvialis and V. mimicus strains differed from those of previously reported Japanese isolates. These differences probably reflect differences in the serogroup of strains.
Assuntos
Lipopolissacarídeos/química , Polissacarídeos Bacterianos/química , Vibrio/química , Vibrio/patogenicidade , Antibacterianos/farmacologia , Aderência Bacteriana , Toxinas Bacterianas/análise , Bangladesh , Células Cultivadas , Reações Cruzadas , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/isolamento & purificação , Monossacarídeos/análise , Antígenos O , Polissacarídeos Bacterianos/imunologia , Polissacarídeos Bacterianos/isolamento & purificação , Vibrio/efeitos dos fármacos , VirulênciaRESUMO
Two new diterpene lactones, suregadolides A (1) and B (2), were isolated from a dichloromethane extract of Suregada multiflora bark. These compounds possess a novel skeleton, which contains a cyclopropane ring bridging C-3 and C-4 of the abietane skeleton. The structures were established on the basis of one- and two-dimensional NMR and other spectroscopic studies. Compound 1 showed moderate inhibitory activity in a mutant yeast strain bioassay.
Assuntos
Antifúngicos/isolamento & purificação , Diterpenos/isolamento & purificação , Euphorbiaceae/química , Lactonas/isolamento & purificação , Plantas Medicinais/química , Antifúngicos/química , Antifúngicos/farmacologia , Bangladesh , Diterpenos/química , Diterpenos/farmacologia , Lactonas/química , Lactonas/farmacologia , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Organismos Geneticamente Modificados , Casca de Planta/química , Saccharomyces cerevisiae/efeitos dos fármacos , EstereoisomerismoRESUMO
Six different prepared mutant strains of Shigella dysenteriae type 1 with various combinations of 'core' plasmids of 140, 6, and 2 Mdal, were cultivated separately and their lipopolysaccharide (LPS) samples were isolated, which on delipidation afforded polysaccharides and oligosaccharides. The LPS and prepared O-antigen polysaccharides were subjected to acid hydrolysis, and the constituent sugars were analysed by paper chromatography and gas liquid chromatography (GLC), using CP Sil 8 CB fused silica capillary column equipped with a flame ionization detector. The mutant strains, harbouring the 6 Mdal plasmid, contained rhamnose, galactose, and N-acetyl glucosamine in their O-antigen polysaccharides with a minor variation in the relative proportions of these sugar constituents as compared to those of the control strain. The sugar composition of the O-antigen polysaccharides prepared from the mutant stains, without the 6 Mdal plasmid but containing 2 or 140 Mdal plasmid, contained galactose and N-acetyl glucosamine but no rhamnose. However, mutant strains with none of the core plasmids contained traces of rhamnose and were devoid of N-acetyl glucosamine, but contained heptose. These results suggest that 6 Mdal plasmid is essentially required for the complete synthesis of O-antigen polysaccharides. However, the 140 and 2 Mdal plasmids might also have an association with synthesis of carbohydrate composition of the O-antigen in S. dysenteriae type 1.
Assuntos
Plasmídeos , Shigella dysenteriae/genética , Carboidratos/química , Lipopolissacarídeos/química , Mutação , Antígenos O , Polissacarídeos Bacterianos/química , Shigella dysenteriae/imunologiaRESUMO
Rhizome of Costus speciosus, tuber of Nephrolepsis tuberosa, and bulb of Stephania hernandifolia, used by the local people and traditional healers in the Eastern Himalayan belt, were studied for their effects on serum glucose levels in nondiabetic and diabetic rat models at different prandial states. The results showed that in nondiabetic rat C speciosus and N tuberosa had no significant effect in the fasting or postprandial state when freeze-dried juices were fed simultaneously with glucose. However, when fed 30 min before the glucose load both C speciosus (p < 0.05) and N tuberosa (p < 0.003) showed hypoglycemic effect. To the contrary, S hernandifolia increased the serum glucose levels of nondiabetic rats in all the series of experiments (p < 0.05 or p < 0.01). In NIDDM model rats N tuberosa opposed the rise in serum glucose level when it was fed 30 min before the glucose load (p < 0.02), whereas S hernandifolia had a tendency to raise the serum glucose level. In IDDM model rats, none of these three freeze-dried juice showed any effect in the fasting state. However, C speciosus showed significant hypoglycemic effect (p < 0.002) when the juice was fed with simultaneous glucose load. In marked contrast to the findings with nondiabetic and NIDDM model rats S hernandifolia showed significant hypoglycemic effect (p < 0.05-0.006) in both the stages (fed simultaneously with, and 30 min before the glucose load) of prandial states of the IDDM model rats. The results indicated that these three plants have interesting possibilities as a source of oral hypoglycemic agents.