Extraction kinetics and physicochemical characteristics of Colombian propolis

Abstract

AbstractPropolis, a resinous matter collected by Apis mellifera bees from exudates of plants, exhibits different biological properties, such as antimicrobial, antifungal, antiviral, and antioxidant activities. Standardization of the extraction of their bioactive compounds is a complex issue in particular for rural regions in developing countries due to the need for specialized equipment and personnel. Herein, kinetic extractions by maceration over 7 days were compared with ultrasound and supercritical fluids extractions in terms of the polyphenolic content obtained. Ultrasound showed the fastest kinetic extraction for each propolis without affecting the antioxidant activity. Supercritical fluids showed the lowest polyphenolic content recovery and no selectivity for antioxidant activity, in agreement with the solubility predictions. The main difference among the extraction methods was the extraction time required to reach the equilibrium concentration. No significant differences in selectivity were observed for the different methods. The antioxidant activity remained almost constant with the extraction method and extraction time, indicating similar extraction kinetics for the extracted polyphenols. We found that the physicochemical characteristics and UV‐vis spectra could be used as predictors of the polyphenolic contents for the studied samples.Practical ApplicationEven though most of the beneficial properties to the human health of the propolis extracts depend largely on the compounds present in the matrix and their extractability, the evaluation of these compounds and their biological activities might be costly and time‐consuming for beekeepers, particularly in developing countries. Also, the extraction method and the extraction time are important decisions that significantly affect the economics of the propolis production process. The main difference among extraction methods was the extraction time required to reach equilibrium and no significant differences in selectivity were observed for the different methods. Moreover, it was found that simple parameters such as ash and moisture can be used as predictors of the polyphenolic contents and antioxidant activity of the propolis, and they can provide important information about the handling during harvest, transport, and storage of the propolis.