ABSTRACT
Aims: To evaluate blood glucose-lowering ability of leaf ashes and compare anti-hyperglycaemic activities of Annona muricata leaf extract and ash. Study Design: Ashes and extract of medicinal plants were assayed using glucose-loaded rats model. Place and Duration of Study: Department of Pharmacognosy, Obafemi Awolowo University, Ile-Ife, Nigeria, between March 2017 and February 2020. Methodology: Adequately prepared ashes of seven plants and A. muricata methanol extract were assayed for anti-hyperglycaemic potentials, using glucose-loaded (10 g/kg, p.o.) Wistar rats that were hyperglycaemic [blood glucose levels ? 7.0 mmol/L] thirty minutes thereafter (T0.0). Groups of 5 rats each, were administered 100, 150, 200 mg/kg of different ashes and A. muricata extract (200 mg/kg). Normal saline and glibenclamide (5 mg/kg) were negative and positive controls, respectively. Their blood glucose levels were determined at 0-4 hours post-extract/ash/drug administration; results analysed using ANOVA followed by the Student-Newman-Keuls’ and Dunnett post-hoc tests. P ? .05 was considered significantly different. Results: 100 mg/kg of Momordica charantia, Azadirachta indica and Eugenia malaccensis leaf ashes was their most active dose, indicating significantly higher extrapancreatic activity. 32, 37, 54, 59 and 36, 43, 50, 48 % reductions elicited by Chromolaena odorata (COLA) and A. muricata (AMLA) ashes (200 mg/kg) at 0.5, 1, 2 and 4 hours, respectively made them the most active ashes. Also, blood glucose levels in glibenclamide (5 mg/kg)-, COLA-, AMLA- and its extract (200 mg/kg)-treated rats were comparable (P > .05) and their anti-hyperglycaemic activity was suggested to be due to the pancreatic (insulinotropic) and extra-pancreatic actions of their constituents. Conclusion: Study justified anti-diabetic ethnomedicinal use of plant-ashes in Nigeria, while doses were recommended for the optimum folkloric usage of these leaf ashes in managing diabetes in the rural areas of Nigeria. The leaf ashes may contain elements with glucose postprandial tolerance factor and insulin stimulating properties.
ABSTRACT
Aims: Appropriate ratios for combining some African ethnomedicinal plants with proven anti-plasmodial activity were determined with the aim of obtaining herbal remedies with higher efficacies. Place and Duration of the Study: Study was conducted in the Department of Pharmacognosy, Obafemi Awolowo University, Ile-Ife Nigeria. Study Design: Infusions of dried powders of three Nigerian ethnomedicinal plants, Eugenia uniflora leaf, Gongronema latifolium root and stem and Artocarpus altilis stem bark, were separately evaluated and in varied combination ratios for their anti-plasmodial activities Methodology: The infusions were separately prepared, concentrated in vacuo, freeze-dried and evaluated at 400mg/kg against Plasmodium berghei berghei parasites, using the Peter’s four-day chemosuppressive mice model. Normal saline and chloroquine (10mg/kg) were negative and positive controls, respectively. 2- and 3-combinations of the infusions were similarly tested. Results: Of the 2-plant combination ratios, 1:1, 1:3, 2:3 of EG and GA elicited percentage chemo suppressions which were comparable (P=.28; P=.07) to those of the single drugs. Only the EG ratios gave activities that were comparable (P=.28) to the positive control in addition to double survival times and high survivor values by EG 2:3 and GA 1:3. However, those of the EA group, gave relatively low values, barely above 20% with only the ratios 2:3 and 3:2 giving values which were significantly (P=.00) higher than negative control with double survival times. The 3-plant combination ratios, EGA 2:1:2 and 3:3:2 gave suppressions that were significantly (P=.00) higher than the negative control with others but comparable (P=.33) activities to those of the individual drugs. The other ratios with low suppression values were relatively inactive. But three ratios, EGA 3:1:2, 2:1:1, 1:1:1 elicited survival times doubled (204, 242 and 202 %) that of the negative control without commensurate high antiplasmodial activities. Conclusion: Ethnomedicinal antimalarial plants should not be combined without a data of previous scientific evaluations.