Crude drug analysis and elemental content of the leaves and stem bark of Adansonia digitata L. (Malvaceae), an indigenous Ghanaian medicinal plant

Adansonia digitata L. is a tree indigenous to Ghana and West Africa. It is traditionally used for medicinal, religious and nutritional purposes. Different parts of the plant are used traditionally for the treatment of diseases such as anaemia, malaria, asthma and diarrhoea among others. It is therefore necessary to provide standard parameters for identification and for the purpose of quality control. This study thus sought to investigate the pharmacognostic characteristics and elemental properties of the leaves and stem bark of A. digitata grown and used in Ghana. The macroscopic and microscopic characteristics, phytochemical, physicochemical, fluorescence and elemental properties of the leaf and stem bark were determined using standard protocols. The results of the study showed that the leaves of A. digitata were palmate compound and alternately arranged with stipules at each node. The outer bark was observed to be grey in color while the inner bark was pink to brown and laticiferous. Anomocytic stomata and stellate trichomes were also observed microscopically on the leaf surface. The powdered stem bark contained brachysclereids and prismatic calcium oxalate crystals. Saponins, tannins, flavonoids and alkaloids were detected in both leaf and stem bark. They additionally exhibited different fluorescence characters in various solvents. The plant contained major and minor nutritional elements in varying quantities. The results of this study can serve as reliable parameters for accurate identification and authentication of A. digitata L. hence ensuring quality

Myrianthus libericus: Possible mechanisms of hypoglycaemic action and in silico prediction of pharmacokinetics and toxicity profile of its bioactive metabolite, friedelan-3-one

The hypoglycaemic and anti-hyperlipidaemic effects of the 70% ethanol stem bark extract of Myrianthus libericus (MLB), used traditionally in the management of diabetes in Ghana, was evaluated in this study using streptozotocin (45 mg/kg)-induced diabetic rats. In vitro hypoglycaemic activities of the extract and one of its principal compounds, friedelan-3-one were then investigated using α-amylase inhibitory and glucose uptake assay in C2C12 myotubes. In silico analysis of the pharmacokinetic and toxicity properties of the compound was also performed. MLB significantly (p < 0.001) reduced the elevated blood glucose levels and corrected considerably (p < 0.01) the altered serum lipid profiles of the diabetic rats which was comparable to glibenclamide (5 mg/kg). Together with friedelan-3-one, the extract markedly inhibited the activity of α-amylase and promoted glucose uptake in C2C12 cells. Whereas MLB significantly (p < 0.001) up-regulated PI3K and PPARγ transcripts with a corresponding increase in GLUT-4 transcripts within the muscle cells, friedelan-3-one only up-regulated PI3K and GLUT-4 transcripts to promote glucose transport. Friedelan-3-one was shown to be non-carcinogenic, non-hepatotoxic, has decent oral bioavailability and a good compound for optimisation into a drug candidate. The study has demonstrated that MLB possess hypoglycaemic and anti-hyperlipidaemic activities and could be used as a therapeutic agent in the management of diabetes mellitus