Microwave hydrodiffusion and gravity model with a blend of high and low power microwave firing for improved yield of phenolics and flavonoids from oyster mushroom

Abstract

Oyster mushrooms are a globally important entity both commercially and therapeutically with immense food value. The work describes a successful application of a unique method of microwave hydrodiffusion and gravity combining optimal mix of high and low power microwave firing for the extraction of phenolics and flavonoids principles from oyster mushroom for the first time. Initial firing of microwaves at higher power level (510 W for 2 min and 340 W for 2 min) was applied followed by sustained microwave firing at 170 W till the completion of the extraction as indicated by physical oozing out of the aqueous extract. Such a combination of microwave firing in microwave hydrodiffusion and gravity (MHG) method (26 min) successfully produced two times more yield of extract with 57.7% ± 2.8 and 82.3% ± 3.7 more content of phenolics and flavonoids, respectively, when compared to 5 h Soxhlet extraction and that too with a better reproducibility. Mapping of individual phenolics/flavonoids were carried out and SEM images were studied for better understanding of the operational aspects. The research aims towards canvassing green technologies as in the near future only those technologies shall survive which are in tandem with environment.