Preliminary studies on in vitro antioxidant and retardation of essential carbohydrate hydrolysing enzymes by some indigenous South African medicinal plants

0575713 - ÚEB 2024 RIV NL eng J - Journal Article
Ogbe, A. A. - Gupta, Shubhpriya - Finnie, J.F. - Van Staden, J.
Preliminary studies on in vitro antioxidant and retardation of essential carbohydrate hydrolysing enzymes by some indigenous South African medicinal plants.
South African Journal of Botany. Roč. 159, AUG (2023), s. 686-696. ISSN 0254-6299. E-ISSN 1727-9321
Institutional support: RVO:61389030
Keywords : Antioxidants * Indigenous plants * Therapeutic agents * α-Amylase * α-Glucosidase
OECD category: Plant sciences, botany
Impact factor: 3.1, year: 2022
Method of publishing: Open access
https://doi.org/10.1016/j.sajb.2023.05.030

Diabetes mellitus (DM) is a chronic metabolic dysfunction characterised by hyperglycaemia. It is strongly linked to oxidative stress. Post-meal elevation of blood glucose levels predisposes humans to Type 2 DM. Retardation of the digestive enzymes α-glucosidase and α-amylase is an efficient therapeutic approach to regulate hyperglycaemia. Many indigenous plants are commonly used in managing DM. However, most of these claims have not been verified scientifically. This study investigated eleven indigenous South African plants for their antioxidant and hypoglycaemic potentials. The phytochemical content (total phenolics, flavonoids and condensed tannins) was quantified colormetrically. The antioxidant potential of crude leaf extracts was evaluated against ferric-reducing antioxidant power (FRAP) and 1,1-Diphenyl-2-picrylhydrazyl (DPPH•). In vitro inhibition of digestive enzymes (α-amylase and α-glucosidase) by the extracts were used to evaluate their antidiabetic activities. Six of the plant species investigated, namely, Catha edulis, Combretum kraussii, Lippia javanica, Endostemon obtusifolius, Psidium guajava and Syzygium cordatum had significant concentrations of flavonoids, total phenolics and/or condensed tannins. These six plant species generally demonstrated significantly lower IC50 values than the positive controls (butylated hydroxyl-toluene (BHT) and acarbose) in the in vitro antioxidant and antidiabetic assays. These results support the use of some of the investigated traditional plants in DM management. The antidiabetic potential of E. obtusifolius, a relatively under-utilized plant, as well as C. kraussii and C. edulis were highlighted as promising species for further investigation as hypoglycaemic agents.
Permanent Link: https://hdl.handle.net/11104/0345455