No abstract

To understand the biological roles of Pediococcus pentosaceus strains as probiotics isolated from the traditional Korean fermented food, Jangajji, Pediococcus pentosaceus was selected based on its high cinnamoyl esterase (CE) and antioxidant activities. The acid and bile stability, intestinal adhesion, antagonistic activity against human pathogens, cholesterol-lowering effects, and immune system stimulation without inflammatory effects were evaluated. Nitric oxide (NO) levels were measured in co-culture with various bacterial stimulants. Fermentation ability was measured by using a broccoli matrix and the sulforaphane levels were measured. Resistance to acidic and bilious conditions and 8% adherence to Caco-2 cells were observed. Cholesterol levels were lowered by 51% by assimilation. Moreover, these strains exhibited immunomodulatory properties with induction of macrophage TNF-α and IL-6 and had microstatic effects on various pathogens. Co-culture with various bacterial stimulants resulted in increased NO production. Fermentation activity was increased with the strains, and higher sulforaphane levels were observed. Therefore, in the future, the applicability of the selected strain to broccoli matrix-based fermented functional foods should be confirmed.

The stability of Saccharomyces cerevisiae is important for industrial usage as a starter culture for the rice wine fermentation process. This study evaluates the effects of diverse protective agents and storage conditions after freeze-drying of the high ethanol-producing S. cerevisiae JBCC-95 strain isolated from traditional rice wine. Four single cryoprotective freeze-drying agents (viz., 10% each of skim milk, lactose, trehalose, and sorbitol) were evaluated, and 10% lactose was determined to be an excellent single protectant. Moreover, the stability of S. cerevisiae JBCC-95 after freeze-drying with 5% skim milk with lactose was greatly enhanced up to 70%, which is 2.5 times higher than the single treatment of lactose. During long-term storage of 30 days at low temperatures, S. cerevisiae JBCC-95 showed less than 13% survival with single protectants, whereas 26% survival was obtained with combined protectants. Physicochemical analysis revealed that freezing of S. cerevisiae JBCC-95 with the selected protectant of 5% skim milk and lactose had no significant effect on the rice wine fermentation (P<0.05). However, the rice wine fermented by freeze-drying S. cerevisiae JBCC-95 with skim milk and lactose as protectants revealed increased levels of esters such as ethyl acetate, isoamyl acetate, and ethyl 2-methylbutyrate and decreased aldehyde contents, indicating that freeze-drying with 5% skim milk and lactose positively affected rice wine fermentation without any significant physicochemical change.