Biologic Propensities and Phytochemical Profile ofVangueria madagascariensisJ. F. Gmelin (Rubiaceae): An Underutilized Native Medicinal Food Plant from Africa

Abstract

Vangueria madagascariensis (VM), consumed for its sweet-sour fruits, is used as a biomedicine for the management of diabetes and bacterial infections in Africa. The study aims to assess the potential of VM on α-amylase, α-glucosidase, glucose movement, and antimicrobial activity. The antioxidant properties were determined by measuring the FRAP, iron chelating activity, and abilities to scavenge DPPH, HOCl, ∙OH, and NO radicals. Leaf decoction, leaf methanol, and unripe fruit methanol extracts were observed to significantly inhibit α-amylase. Active extracts against α-glucosidase were unripe fruit methanol, unripe fruit decoction, leaf decoction, and ripe fruit methanol, which were significantly lower than acarbose. Kinetic studies revealed a mixed noncompetitive type of inhibition. Leaf methanolic extract was active against S. aureus and E. coli. Total phenolic content showed a strong significant positive correlation (r = 0.88) with FRAP. Methanolic leaf extract showed a more efficient NO scavenging potential and was significantly lower than ascorbic acid. Concerning ∙OH-mediated DNA degradation, only the methanol extracts of leaf, unripe fruit, and ripe fruit had IC50 values which were significantly lower than α-tocopherol. Given the dearth of information on the biologic propensities of VM, this study has established valuable primary information which has opened new perspectives for further pharmacological research.

Characteristics of proanthocyanidins in leaves of Chamaecyparis obtusa var. formosana as strong α‐glucosidase inhibitors

“…However, there was a significant and moderate correlation between proanthocyanidin contents and log(1/IC 50 ) values ( R = 0.6) without the extreme values. Some studies have demonstrated a positive correlation between α ‐glucosidase‐inhibitory activities and proanthocyanidin contents, whereas others have reported no positive relationship . In our study, α ‐glucosidase‐inhibitory activities and proanthocyanidin contents might be related.…”

Evaluation of antioxidant, enzyme inhibition, and cytotoxic activity of three anthraquinones (alizarin, purpurin, and quinizarin)

“…[35][36][37][38] On the other hand, several studies showed lower correlation between antioxidant and enzyme inhibitory effects. 39,40 At this point, it seems to the contradictory results are most probably due to differences in chemical structure, functional groups, and in the methodology used. Up to date, there have been a few reports on enzyme inhibitory effects of AQs.…”

Free radical scavenging, α-glucosidase inhibitory and lipase inhibitory activities of eighteen Sudanese medicinal plants

“… MAPRI-H.Y.6/005 17 Vangueria madagascariensis J.F.Gmel. Rubiaceae Fruit El-Kirkir Used in the treatment of diabetes mellitus and bacterial infections [ 61 ]. MAPRI-H.W.45/95 18 Ziziphus spina-christi L. Rhamnaceae Roots Sidir Used in the treatment of gonorrhea, fever, as anti-spasmodic and anti-purgative [ 17 , 62 ].…”