Hydrothermal extraction and micronization in a one-step process for enhancement of β–glucan concentrate at subcritical water conditions

•β–glucan compounds have been extracted from Hordeum vulgare L. and Ganoderma lucidum by using subcritical water way.•The extracted β–glucan compounds were successfully concentrated in the fine particles form via micronization in one-step process.•The extraction-micronization system herein is a viable manner and may update information for the phytochemical compounds extraction-micronization in subcritical water conditions.