Physicochemical Characteristics, Total Phenolic Content and Free Radical Scavenging Activity of Apple (Malus Domestica) Peel Powder

Abstract

Apple peel is considered as a waste product in many fruit industries but it is a noteworthy source of nutrients and phytochemicals, particularly polyphenols which have the ability to scavenge free radicals. Objectives: To study the physicochemical properties of apple (Malus domestica) peel powder, as well as its TPC and free radical scavenging activities. Methods: Proximate analysis of the apple peels powder was carried out. Total polyphenol content of apple peel powder was determined. The total content of phenolic compounds was expressed as gallic acid equivalent, i.e. mg GAE/100g of extract dry weight of sample. Results: The results of physicochemical characteristics moisture (7.65±0.88%), ash (2.50±0.35%), fat (1.18±0.02%), fiber (15.25±1.03%), protein (2.79±0.05%), carbohydrates (71.0±2.30%) and energy were 312±4.70 Kcal/100g. The total phenolic contents in the methanolic extract of apple peel powder were 320±5.4 mg GAE/100g while in H2O extract 201±4.20 mg/100g. The findings of the apple peel powder's methanolic extract's capacity to scavenge free radicals varied from 25.40±1.30—69.2±3.80%, while those of the water extract were 14.30±1.05—45.62±1.90%  and BHT were 17.8±1.15—51.62±2.15%  at concentration 20-100 µg/ml. Conclusions: The outcomes showed that both apple peel powder extracts had promising total polyphenols and have strong free radical scavenging activity. These findings suggest that the apple peel powder act as robust naturally occurring antioxidants and may be employed as a preventative therapy for several oxidative stress-related degenerative disorders.