Potential prebiotic and antibacterial activities of fucoidan from Laminaria japonica

Fucoidan from Laminaria japonica became sterilized with an autoclave and ultraviolet (UV) radiation. Potential prebiotic and antibacterial activities of sterilized fucoidans (SF) were the subject of investigation. Molecular weight, monosaccharide composition, FTIR, and NMR spectra of SF underwent evaluations to elucidate the relationship between the structure and activities of SF. The growth of Lactobacillus rhamnosus GG and L. acidophilus with autoclave sterilized fucoidan (ASF) and the growth of L. plantarum, L. gasseri, L. paracasei, and L. reuteri with UV sterilized fucoidan (USF) increased significantly. Also, fucoidan was vastly more effective than fructooligosaccharides in improving the growth of L. gasseri, L. reuteri, and L. paracasei. The growth of Escherichia coli and Bacillus cereus decreased at each SF concentration. ASF was more effective against E. coli, B. cereus, and Staphylococcus aureus than the USF efficiency. However, USF exhibited more inhibitory effects on the growth of Enterobacteriaceae compared to the ASF efficiency. When comparing the ASF and USF, autoclave caused a considerable decrease in molecular weight and uronic acid content, increased fucose and galactose, and made no significant changes in NMR spectra. Fucoidan effectively promoted probiotic bacterial growth and reduced pathogenic outbreaks in the medium. Therefore, it can occur as a new algal prebiotic and antibacterial agent.