Objective:To study the antidiabetic and antioxidant activities of nipa palm vinegar (NPV) used in traditional Malay medicine for treating diabetes.Methods:NPV was extracted using liquid-liquid extraction method and the obtained samples were subjected to antidiabetic studies using normal and streptozotocin-induced diabetic rat models whereas antidoxidant activities were investigated viain vitroantioxidant tests namely 2,2-diphenyl-1-picrylhydrazyl and 2,2’-azinobis-3-ethylbenzothiozoline-6-sulfonic acid free radicals scavenging activities and the reducing power assay.Results:Single administration of NPV and its extracts were not effective in both normal and diabetic rats. In intraperitoneal glucose tolerance test, NPV and its aqueous extract showed significant blood glucose lowering effect. In the sub-acute study, compared with the diabetic control, aqueous extract of NPV showed the most notable blood glucose lowering effect (56.6%) and a significant improvement in serum insulin levels (79.8%, P<0.05). To assess NPV’s antioxidant activity, threein vitro antioxidant tests were employed:2,2-diphenyl-1-picryhydrazyl and 2,2’-azinobis-3-ethylbenzothiozoline-6-sulfonic acid free radical-scavenging assays, and the reducing power assay. Ethyl acetate extract had the greatest antioxidant potential and content of phenolic and flavonoid compounds. A linear positive correlation between the antioxidant parameters was observed. Chemical profiling analysis of aqueous extract of NPV revealed the presence of acetic acid (35.25%), the main active constituent which significantly contributed to the observed antidiabetic activity.Conclusions:Aqueous extract of NPV possesses antihyperglycaemic activities comparable to the metformin, while the ethyl acetate extract precipitated significant antioxidant effects attributable to its high phenolic content. These findings suggest that antioxidant compounds of NPV do not contribute much towards the overall observed antidiabetic effect.

Objective: To elucidate the in vivo hypoglycemic capability, antihyperglycemic and antihyperlipidemic activities of Pereskia bleo (Kunth) leaves extracts and bioactive fraction. Methods: The various solvent extracts of Pereskia bleo were investigated for the hypoglycemic and antihyperglycemic activities using a relevant in vivo normal rat model and streptozotocin-induced diabetic rat model with glibenclamide and metformin utilized as positive controls. The effects of the most potent extract and its bioactive fraction on the insulin level, lipid profile and body weight of the diabetic rats were also analyzed. Results: All the extracts showed no hypoglycemic effect while petroleum ether, chloroform and aqueous extracts demonstrated significant (P<0.05) reduction in blood sugar level in the intraperitoneal glucose tolerance test. Aqueous extract and aqueous fraction significantly (P<0.05) reduced the blood glucose level in streptozotocin-induced diabetic rats as early as day 6 compared to the diabetic control as well as significantly restored the serum insulin of diabetic rats. Moreover, the aqueous extract and aqueous fraction disclosed a significant (P<0.05) reduction in total cholesterol, triglycerides, and low-density lipoprotein levels. An elevation in high-density lipoprotein as well as improved body weight loss of the diabetic rats were also observed. Conclusions: In summary, Pereskia bleo appears effective in the management of diabetes and correlated impairments arising from high blood sugar level. Further studies will possibly bring about the discovery of effective and secure plant derived antidiabetic drugs.

Objectives: To study the antidiabetic and antioxidant activities of nipa palm vinegar (NPV) used in traditional Malay medicine for treating diabetes. Methods: NPV was extracted using liquid-liquid extraction method and the obtained samples were subjected to antidiabetic studies using normal and streptozotocin-induced diabetic rat models whereas antidoxidant activities were investigated via in vitro antioxidant tests namely 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis-3-ethylbenzothiozoline-6-sulfonic acid free radicals scavenging activities and the reducing power assay. Results: Single administration of NPV and its extracts were not effective in both normal and diabetic rats. In intraperitoneal glucose tolerance test, NPV and its aqueous extract showed significant blood glucose lowering effect. In the sub-acute study, compared with the diabetic control, aqueous extract of NPV showed the most notable blood glucose lowering effect (56.6%) and a significant improvement in serum insulin levels (79.8%, P < 0.05). To assess NPV's antioxidant activity, three in vitro antioxidant tests were employed: 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis-3-ethylbenzothiozoline-6-sulfonic acid free radical-scavenging assays, and the reducing power assay. Ethyl acetate extract had the greatest antioxidant potential and content of phenolic and flavonoid compounds. A linear positive correlation between the antioxidant parameters was observed. Chemical profiling analysis of aqueous extract of NPV revealed the presence of acetic acid (35.25%), the main active constituent which significantly contributed to the observed antidiabetic activity. Conclusions: Aqueous extract of NPV possesses antihyperglycaemic activities comparable to the metformin, while the ethyl acetate extract precipitated significant antioxidant effects attributable to its high phenolic content. These findings suggest that antioxidant compounds of NPV do not contribute much towards the overall observed antidiabetic effect.