Abstract: Polyhydroxybutyrate (PHB) is an important lipophilic carbon-based energy storage polymer in microbial cells. It is biodegradable and biocompatible, serving as a new type of prebiotic, also known as a “ketogenic substance”. PHB is a natural product existing in microorganisms. In food processing, PHB can be used as a functional additive, which can not only improve the texture and taste of foods, but also regulate the human intestinal microecology through its prebiotic function. Consequently, it plays a positive role in maintaining intestinal health and enhancing the body’s immunity. This article mainly reviews the functional mechanism, production and application of PHB in foods, and explores the production and optimization strategies for PHB. Through analyzing the functional mechanism of PHB as a prebiotic and its application effects in different fields, this article aims to provide a theoretical reference for the application research of PHB.

Key words: polyhydroxybutyrate; prebiotics; gut health; immunomodulation; food processing