Preparation and structural characterization of pullulan and whey protein isolate-based electrospun nanofiber

Abstract

The impact of blended ratios was analyzed on the development and characterization of electrospun fibers using various combinations of pullulan (PUL) and whey protein isolate (WPI). The physical parameters like apparent viscosity, electrical conductivity and surface tension of blended solutions were improved after the addition of PUL in the blends, resulting in a uniform electrospun nanofiber. Scanning electron microscope (SEM) of nanofibers revealed bead-free, smooth and uniform structural conformation. Whereas, the uniformity of nanofiber was compromised by using higher concentrations of WPI in the blend. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD) and Thermogravimetry analysis further confirmed the strong molecular interaction between polysaccharide and protein. The incorporation of WPI in PUL based electrospun nanofibers enhanced hydrophobicity, potentially facilitating the delivery of bioactive compounds. The WPI and PUL:WPI-based nanofibers demonstrated robust antioxidant potential, due to the presence of total phenolic contents (TPC). The stability of PUL interaction with WPI (β-lactoglobulin and α-lactalbumin) was confirmed through hydro-carbon (C–H) and hydrogen bond interactions by molecular docking. Finally, we can conclude that polysaccharide and protein-based nanofiber can be used to deliver bioactive compounds in food and pharmaceutical industries.