Phenolic Composition and Inhibitory Ability of Methanolic Extract from Pumpkin (Cucurbita pepo L) Seeds on Fe-induced Thiobarbituric acid reactive species in Albino Rat’s Testicular Tissue In-Vitro.

Pumpkin seed has been associated with myriad of medicinal uses in different part of the world. In this study, phenolic composition and Fe2+ induced thiobarbituric acid reactive species (TBARS) inhibitory ability of methanolic extract from pumpkin seeds in rat’s testes homogenates were determined. The extract was prepared with 80% methanol (v/v) and the radicals [(1,1-diphenyl–2 picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS)] scavenging, Fe2+ chelation and ferric reducing abilities of the extract were carried out. The phenolics composition was also investigated using gas chromatography couple with flame ionization detector (GC-FID). The GC analysis revealed the presence of vallinic, coumaric protocatechuic, caffeic, ferulic and sinapinic acids, and apigenin, quercetin, luteolin, kaempferol as the dominant phenolic compounds. The results revealed that the extract inhibited Fe2+-induced TBARS, scavenge DPPH radical and chelate Fe2+ in a dose dependent manner. The extract also scavenged ABTS radical and reduced Fe2+ to Fe3+. Although, the standard used had higher effect compared to the extract, nevertheless, the TBARs inhibitory potential of the extracts clearly gives an insight on the protective potentials against oxidative induce testicular damage that might lead to male infertility if unchecked. These abilities could however be linked to the presence of polyphenolic compounds.

Antioxidant properties and in vitro alpha-amylase and alpha-glucosidase inhibitory properties of phenolics constituents from different varieties of corchorus spp.

This study investigated the phenolic constituents, antioxidant properties and effect of aqueous extracts from some Corchorus species [C. aestuans, C. bougoudo, C. capsularis, C. olitorius and C. urtifolicus] on alpha-amylase and alpha-glucosidase activities in vitro. Gas Chromatography with Flame Ionization Detector [GC-FID] was used to characterize the phenolic constituents. Aqueous extracts were prepared weight/volume [w/v] and their effects on alpha-amylase and alpha-glucosidase activities, Fe[2+] induced lipid peroxidation, and 1,1-diphenyl[-2] picrylhydrazyl [DPPH] radical scavenging properties were determined. Fe[2+] chelating abilities and Ferric Reducing Antioxidant Power [FRAP] properties were also studied. The predominant phenolics detected by GCFID were kaempferol, rutin, apigenin, luteolin, caffeic acid and quercetin. The results showed that all the Corchorus species significantly [P < 0.05] inhibited alpha-amylase and alpha-glucosidase activities dose-dependently [0-8 micro g/ml]. C. olitorius had the highest alpha-amylase inhibitory ability while C. bougoudo demonstrated the maximum alpha-glucosidase inhibition. However, all the Corchorus species inhibited alpha-glucosidase better than alpha-amylase and also exhibited antioxidant properties. The enzyme inhibitory and antioxidant properties exhibited by the Corchorus species could be attributed to their phenolic constituents and vitamin C content; a possible mechanism by which Corchorus species could elicit therapeutic effects on type 2 diabetes mellitus as obtained in folklore medicine