Functional and antioxidant characteristics of the dietary fiber extracted from pearl millet

Abstract

The envisioned research aims to investigate the functional characteristics of pearl millet's dietary fiber to meet the growing demand for nutraceutical dietary fibers. Our results demonstrate that fiber extracted using various chemical-intensive and enzymatic methods possesses an impressive prebiotic index, cholesterol-absorbing capacity, and remarkable oil and water-holding capabilities (WHC), making it a valuable asset for the food processing industry. The fiber extracted through the alkali-mediated (alkSDF) approach demonstrated the highest WHC (9.22 g/g) compared to the lowest values (1.01 g/g) observed through enzymatic treatment. Likewise, the highest free radical scavenging activity (92%) using ABTS assay was noted for alkSDF, whereas the enzymatic approach exhibited the lowest antioxidant characteristics (11%). A comprehensive morphological analysis indicated smooth surface with acid extracted fiber as compared to rough surface and higher crystallinity obtained by alkali treatment. Specifically, dietary fiber obtained through amylase-assisted ultrasonication exhibits improved thermal properties and superior abilities to absorb glucose (7.53 mM/g) and cholesterol (1.43 mg/g). Moreover, in-silico analysis has revealed the crucial active site amino acids involved in amylose binding and substrate catalysis, facilitating the release of reducing sugars into the medium. The structural and functional properties of pearl millet fiber establish it as a highly effective and accessible food supplement for various biomedical applications.