Water-soluble non-starch polysaccharides of root and tuber crops: extraction, characteristics, properties, bioactivities, and applications.

This review critically evaluates and discusses groundwork and recent studies on the extraction, characteristics, properties, bioactivities, and applications of the water-soluble non-starch polysaccharides (WS-NSPs) of root and tuber crops. Early studies have focused on the use of conventional extraction methods for the extraction of the WS-NSPs and there are limited information on the characteristics and properties of the extracted materials. In recent years, novel extraction techniques such as microwave, ultrasound, and enzyme-assisted extractions have been utilized to improve the yield and functionality of the WS-NSPs. However, low yield and co-extraction of other biological compounds remain a challenging obstacle for commercial uses. A better understanding of the characteristics and properties was recently afforded by employing advanced analytical techniques to investigate the chemical composition and molecular structures of the WS-NSPs. Recent bioactivities of the WS-NSPs that demonstrated their potential in the prevention and management of metabolic diseases like diabetes, obesity, cancer, and in improving gut health and immunity had received considerable attention. Also, many studies have confirmed the potential use of the WS-NSPs of root and tuber crops in a wide range of food and pharmaceutical applications. These bioactivities of WS-NSPs warrant further investigations on this interesting biomaterial.