Enhancing bioactive content in Malus sylvestris peel extract for antioxidant source using microwave-assisted extraction (MAE) and predicting the potential of ant nests

Abstract

Background The apple peel is one of the byproducts of apple beverage production that is still underutilized. While considerable information regarding apple peel extract is available, its utilization remains limited. Yet, apple peel contains numerous bioactive components that offer various health benefits. Based on this, information regarding the bioactive components in apple peel and their health potential is required. Methods The research consisted of two stages, namely Stage 1, which involved in silico analysis of the bioactive content in apples and predicted the potential of ant nests using the Structural Activity Relationship (SAR) approach Pass Online. In Stage 2, in vitro analysis of apple peel extraction as a natural antioxidant source was conducted using treatment time radiation (3 minutes, 6 minutes, 9 minutes, and 12 minutes). The extract was characterized based on phenolic, flavonoid, antioxidant activity, quercetin, and functional groups using Fourier Transform Infrared Spectroscopy (FTIR). Results Stage 1: gave results that several bioactive were identified such as chlorogenic acid, epicatechin, phloridzin, catechin, hyperoside, quercitrin, quercetin, and pectin. Based on SAR, the bioactive compounds have functional potential as anti-inflammatory, lipid metabolism regulators, free radical scavengers, lipid peroxidase inhibitors, antihypercholesterolemic, and insulin promoters. Stage 2: Radiation times of the MAE method had a significant effect (P<0.05) on the phenolic content, and antioxidant activity and was highly significant (P<0.01) on the flavonoid content of Malus sylvestris. Radiation time for 12 minutes of MAE gave higher phenolic, flavonoid, and antioxidant activity of Malus sylvestris peel extract. The IR spectra of the Malus sylvestris extract increased as the radiation time increased. Conclusions The optimum radiation time was at 12 minutes with the result of phenolic content at 14.73 mg GAE/g, flavonoid content at 29,62 ppm, antioxidant activity at 95,09%, and the IR spectra at 1031.92 cm−1, 1390.68 cm−1, 2833.43 cm−1, 2945.3 cm−1, 3346.5 cm−1, 3354.21 cm−1.