Synergistic Polyphenol Recovery From Embelia ribes Using MP-UAE, UAE, and MAE and In Silico Studies Against HCV Protease.

Abstract

Embelia ribes (ER) is well regarded in herbal medicine for its therapeutic properties, making the development of efficient methods to obtain its bioactive extracts of high yield essential. This study evaluated and optimized three extraction techniques, microwave-pretreated ultrasound-assisted extraction (MP-UAE), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE), to isolate bioactive compounds from ER seeds. Embelin, a primary bioactive, was quantified in the optimized extracts, while 13 bioactives, including embelin, were analyzed through in silico studies targeting HCV NS3 protease. Process optimization using response surface methodology (RSM) focused on key parameters: total phenolic content (TPC), total flavonoid content (TFC), DPPH radical scavenging activity (DRSA), and ABTS radical scavenging activity (ARSA). Experimental results validated the models, with MP-UAE yielding the highest TPC (183.00 mg GAE/g DW), TFC (54.54 mg RE/g DW), DRSA (72.80%), and ARSA (81.33%). Optimized conditions included microwave power of 238 W, 48-min sonication, and a 19-mL/g solvent-to-plant ratio for MP-UAE. Embelin content, measured spectrophotometrically, was highest in MP-UAE at 39.98 ± 0.97 mg/g DW. Molecular docking using Maestro 12.5 identified amentoflavone (-8.991 kcal/mol), embelin (-8.152 kcal/mol), quercetin (-8.107 kcal/mol), and aloe-emodin (-8.014 kcal/mol) as top compounds, surpassing the standard drug boceprevir (-5.342 kcal/mol). This study establishes a green, efficient extraction method for ER seed bioactives, highlighting the antiviral potential of embelin and contributing to herb-based pharmaceutical advancements, particularly in antiviral drug development.