Study on the in Vitro Antioxidant and Bile Salts Binding Activity of the Dietary Fibers from Seven Edible Rraditional Chinese Medicines

The objective of this study was to explore the biological activity of dietary fiber in edible traditional Chinese medicines. Seven Chinese medicines (Codonopsis pilosula, Astragali radix, Chinese yam, liquorice, Ganoderma lucidum, Panax ginseng, Panax quinquefolium) were chose to extract the water-soluble dietary fiber (soluble dietary fiber, SDF), water-insoluble dietary fiber (insoluble dietary fiber, IDF) and total dietary fiber (total dietary fiber, TDF). The physicochemical properties, in vitro antioxidant activity and bile salts binding ability of dietary fibers were studied. The results showed that the Codonopsis pilosula TDF, Ganoderma lucidum TDF and ginseng TDF had the highest water-holding capacity (11.26 g/g), oil-holding capacity (6.36 g/g) and swelling capacity (9.12 mL/g), respectively. Astragali radix SDF, Chinese yam SDF and ginseng TDF had the highest DPPH scavenging rate (96.27%), hydroxyl radical scavenging rate (97.20%), and the superoxide anion radical scavenging rate (60.32%), respectively. Ginseng TDF had the highest total antioxidant capacity (2283.39 μmol/L/FeSO₄). Ginseng TDF had the highest binding rate to sodium glycinate (59.87%), Astragali radix TDF had the highest binding rate to sodium taurocholate (51.52%). The average binding rate of dietary fibers to sodium glycosyl cholate (34.12%~53.73%) were higher than that of sodium taurocholate (28.16%~45.47%). This study shows that seven edible traditional Chinese medicines had good physicochemical properties and biological activity, which give them development potential of functional food.