In Vitro and In Vivo Comparative Evaluation of Biological Activities in Freshly Homogenized and Oven-Dried Chrysophyllum albidum G. Don Fruits Extracts and Their Ethyl Acetate Fractions

Abstract

Chrysophyllum albidum (African star apple) is an edible fruit, found in tropical regions of the world. C. albidum fruits wastages have been reported at its peak season in Nigeria. Conventional oven drying has been reported to impart on the nutritional quality and heat-labile bioactive constituents in fruits. This study was designed to comparatively evaluate the in vitro and in vivo biological activities of extracts and fractions from freshly homogenized and oven-dried fruits of C. albidum. C. albidum fruits were obtained from a farm stead at Oyo town, Oyo state, Nigeria. The fruits were rinsed, deseeded and separated into two parts. One part was homogenized, the second part was oven-dried at 40oC for one week. The homogenized and oven dried fruits were extracted in ethanol (70%) for 72-hours and the extracts obtained were sequentially partitioned in n-hexane and ethyl acetate. The phenolic contents were determined spectrophotometrically. The extracts and ethyl acetate fraction were tested for in vitro antioxidant activity using DPPH, NO, phosphomolybdate activity assays. In-vitro acetylcholinesterase inhibitory activity assay was also determined. Antidepressant-like effect of the extracts and ethyl acetate fraction were determined in male Swiss mice using the TST, FST and OFT. The oven-dried extract and its ethyl acetate fraction gave a higher extraction yield than the homogenized extract and its ethyl acetate fractions. Total phenolic content and in vitro antioxidant activity were significantly higher in homogenized extract and fraction than the corresponding oven-dried extract and fraction. The oven-dried ethyl acetate fraction had a higher total flavonoid content and flavonoid: phenolic ratio than the corresponding homogenized ethyl acetate fraction. The ethyl acetate fraction of oven-dried extract exhibited a significantly greater reduction in immobility time in the FST than the corresponding fraction of the homogenized extract. The results suggest that oven drying processing of fruits of Chrysophyllum albidum might affect the total phenolic content and in vitro antioxidant activity but not the in vivo biological activity.