Effects of Solvent Type and their Purity on the Yields of Total Phenolic, Total Flavonoids and Antioxidant Activity in Extracts of Longan and Lotkon Peels

Abstract

Lotkon and longan are popular plants with fruits that are rich in nutrients. The pulp is the most commonly ingested component of both fruits. The potential of additional fruit components, such as the peel and the seed, as repositories of significant bioactive substances has not yet been adequately investigated.The objectives of this study was to investigate how three types of solvent (ethanol, methanol, and acetone) affected the yield of total phenolic content (TPC), total flavonoids content (TFC) and DPPH radical scavenging activity of extracts from lotkon and longan peels. Using the maceration process, antioxidant and bioactive chemicals were extracted from fruit samples. For this procedure, 10 ml of solvent (1:10 w/v) was applied to universal bottles containing 1 gm of peel powder. The total phenolic content was calculated using a modified Folin-Ciocalteu method. The results showed that the 50% methanol extracts for longan peel displayed the highest levels of TPC, TFC, and DPPH free radical scavenging activities. The TPC varied for both peel extracts (longan and lotkon) from 343.39±0.22j to 425.55±0.19a, 121.63±0.29j to 321.54±0.12a mg GAE/100g dry weight;TFC from 48.24±0.09j to 86.24±0.11a , 6.47±0.37g to 15.37±0.11a mg QE/100g dry weight and DPPH radical scavenging activity from 30.79±0.03j to 60.01±0.02a %,25.84±0.01j to 54.76±0.03a % respectively. Total phenolic content extraction yields from lotkon and longan peels were significantly (p<0.05) affected by solvent type and their purity.The findings demonstrated that longan peel extract had significantly more total phenolic content than lotkon peel extract. All of the available solvents were used to evaluate the extracts of longan and lotkon peels, 50% methanol was shown to be the most effective at extracting total phenolic, total flavonoid and antioxidant activity (DPPH). The results of this study provide a useful roadmap for the food industry in identifying the best conditions for extracting antioxidants and desirable phenolic compounds from lotkon and longan peels, as well as a strong basis for additional research in the future.