VOLUME 16 NUMBER 2 (July to December 2023)

Optimized green extraction method for the recovery of phenolics from bignay [Antidesma bunius (L.) Spreng] pomace

The main objective of this research was to optimize a green extraction technique for the recovery of phenolic compounds from freeze-dried bignay [Antidesma bunius (L.) Spreng.] pomace. Plackett-Burman design (PBD) was used to screen significant factors affecting the recovery of phenolic compounds from bignay pomace and Response Surface Methodology (RSM), specifically Box-Behnken design (BBD), was used to determine the optimum levels of the identified significant factors. The influence of solvent concentration (water/ethanol 0–100% [v/v]), sample concentration (1–15 % [w/v]), solvent pH (pH 2–7), incubation time (13–180 min), incubation temperature (30–70 °C), sonication time (0–90 min), and agitation (0–300 rpm) on the total phenolic compounds of the extract were investigated. The total monomeric anthocyanins, flavonoids, catechin contents, and antioxidant properties of the optimized extract were also determined. Results of PBD (adjusted R²= 0.9820) and BBD (adjusted R²= 0.8838) experiments were validated and the optimum conditions for phenolic compound extraction from bignay pomace were achieved with 10.41% sample in distilled water incubated at 30 °C for 13 min. Higher recovery of phenolics was attained when water was used as an extraction solvent under optimal extraction conditions. The bignay pomace extract features significant amounts of phenolic compounds and exhibits high antioxidant activities relative to other fruit peels reported in literature. The resulting extract is free of organic solvent residues and features significant polyphenolic compounds with high antioxidant activities, indicating its potential as a functional food ingredient. This optimized green extraction method offers an economical and sustainable alternative for recovering phenolic compounds from bignay pomace.