Ultrasound-assisted green extraction of antioxidant and antimicrobial resins from Cannabis sativa for potential pharmaceutical applications

Abstract

Objective: To develop a green and efficient ultrasound-assisted extraction (UAE) process to obtain bioactive resins from Cannabis sativa with potential pharmaceutical applications, optimizing extraction parameters to maximize antioxidant capacity and total polyphenol content. Significance: UAE using ethanol under mild temperature and time conditions as a green technique was applied to reduce solvent consumption, energy demand, and extraction time while preserving thermolabile bioactive compounds. Optimizing UAE enables the recovery of cannabinoid- and terpene-rich extracts that may serve as natural active pharmaceutical ingredients or functional excipients for drug development. This study integrates a Doehlert-based optimization of UAE with a functional evaluation of antioxidant efficiency and antimicrobial activity, providing a comprehensive framework for the development of cannabis-derived pharmaceutical ingredients. Methods: A Doehlert experimental design combined with response surface methodology was employed to optimize temperature and extraction time. The optimized extract was characterized for its phytochemical composition. Antimicrobial activity was evaluated against Gram-positive and Gram-negative bacterial strains to assess potential therapeutic relevance. Results: Under optimal conditions (54.5°C, 28min 25s), the extract showed a total phenolic content of approximately 0.11mg gallic acid/mg resin and an IC50 value of about 0.24mg resin/ mL extract, indicating enhanced antioxidant performance compared to non-optimized conditions. Also, it showed selective bactericidal activity against Staphylococcus aureus ATCC 25923 and Staphylococcus epidermidis ATCC 12228, while Gram-negative strains remained resistant. Conclusion: UAE extraction efficiently recovered antioxidant and selectively antimicrobial compounds from Cannabis sativa resins under mild, eco-friendly conditions, supporting their potential use as bioactive ingredients in pharmaceuticals.