@article {2040, title = {Antidiabetic and Hypoglycaemic Activities of Commonly Used African Traditional Vegetables}, journal = {Pharmacognosy Journal}, volume = {15}, year = {2023}, month = {June 2023}, pages = {339-356}, type = {Research Article}, chapter = {339}, abstract = {

Introduction: Diabetes mellitus is a common and complex metabolic disorder associated with high blood glucose levels leading to complications. Adopting a sedentary lifestyle characterized by low physical activity and consumption of high-energy diets contributes to the development of diabetes mellitus. Lifestyle changes and the use of pharmacological agents that target particular biochemical pathways involved in nutrient metabolism are currently used as management guidelines for managing risk factors associated with diabetes mellitus. The use of prescription medications for an extended period is linked to several negative side effects. Alternative management strategies of risk factors linked to diabetes mellitus involve the use of African leafy vegetables. African leafy vegetables contain a variety of biologically active compounds that provide health benefits. These crops have the potential to be a valuable source of new oral hypoglycemic agents for diabetes management. This review analyses the antidiabetic activities of nine African leafy vegetables whilst also defining the gap areas for future research. Methods: Data was acquired via electronic search engines of which only peer-reviewed papers published in journals were considered. Results: African traditional vegetables showed diverse in vitro and in vivo antidiabetic activities. Conclusions: There is an urgent need to document and use the knowledge of African leafy vegetables that have potential in the treatment and management of diabetes mellitus.

}, keywords = {African traditional vegetables, Antidiabetic, Diabetes mellitus, Hypoglycaemic, Phytochemicals.}, doi = {10.5530/pj.2023.15.84}, author = {Nolitha Nkobole and Lavhelesani R. Managa and Gerhard Prinsloo} } @article {1724, title = {In vitro α-Glucosidase and α-Amylase Activities of Wild and Cultivated Amaranthus spp. and Isolated Compounds}, journal = {Pharmacognosy Journal}, volume = {13}, year = {2021}, month = {December 2021}, pages = {1614-1620}, type = {Original Article}, chapter = {1614}, abstract = {

Introduction: Diabetes mellitus is a serious metabolic disorder that affects many South Africans. There is urgent need for alternative and affordable diabetic therapy from edible wild plants which have been used by the indigenous people for many years. This study presents in vitro antidiabetic effects of methanol leaf extracts of wild and cultivated Amaranthus spp. and isolated compounds. Methods: The inhibitory effects against yeast α-glucosidase and porcine α-amylase were determined using a dilution series of ethanolic extracts of wild and cultivated leaf extracts and isolated compounds of Amaranthus spp. The aerial parts of the plant material were subjected to silica gel chromatography to yield three compounds. Results: Wild A. hybridus showed potent α-glucosidase enzyme activity (89.92{\textpm}0.04\%) at the lowest concentration tested (0.125 mg/mL) in comparison to acarbose which exhibited 80.20{\textpm}0.13\% inhibition at the same concentration. Cultivated A. cruentus extracts inhibited α-glucosidase enzyme activity (84.95 {\textpm} 0.04\%) at the lowest concentration compared to cultivated A. hybridus which exhibited inhibitory activities of 72.28 {\textpm} 0.06\%. In addition, three compounds namely, α-spinasterol, palmitic acid and pheophorbide A-methyl ester isolated from wild A.cruentus were tested for in vitro antidiabetic activity. Palmitic acid demonstrated the highest inhibition against α-glucosidase for all the concentrations tested. Tested separately, the isolated compounds were weaker α-amylase enzyme inhibitors however, when the compounds were combined, inhibition of α-amylase increased to 58.49{\textpm} 002\% at 0.5 mg/mL. Conclusions: Extracts and compounds of Amaranthus showed strong α-glucosidase activity inhibition and mild α-amylase activity inhibition suggesting that the extracts and compounds slow glucose absorption.

}, keywords = {α-Amylase; α-glucosidase; Blood glucose; Diabetes mellitus; Hyperglycemia; Phytochemicals.}, doi = {10.5530/pj.2021.13.208}, author = {Nolitha Nkobole and Olusola Bodede and Ahmed A Hussein and Gerhard Prinsloo} }