A “PAKU-PAKU KOUBO-KUN” containing yeast and mulberry extract postprandial glycemic control in healthy Japanese men and women: a randomized, placebo-controlled, crossover study

Objective: This study’s purpose was to verify the PAKU-PAKU KOUBO-KUN (PPKK) containing yeast and mulberry extract concentrate’s effects on suppressing elevated postprandial blood glucose (PBG).Methods: Two randomized, placebo-controlled, crossover studies (TRIAL-1 and TRIAL-2) were conducted. Both studies included healthy Japanese adults with a maximum PBG concentration (Cmax) in the range of 140–199 mg/dL. Study subjects were randomly assigned to take PPKK or placebo food. Then subjects consumed 200 g of cooked rice within 10 minutes of test food consumption. Blood glucose (BG) levels were evaluated before intervention, and 30 min, 60 min, 90 min, and 120 min after consumption. The main endpoint was the incremental area under the curve (IAUC) of PBG.Results: The analysis included 36 subjects in TRIAL-1 and 41 subjects in TRIAL-2. A combined analysis (n = 71) was conducted. Both individual studies and combined analysis showed that PPKK significantly reduced the IAUC of PBG. In particular, BG levels were significantly lower at 30 min, 60 min, and 90 min after intervention. No adverse effects were identified. Conclusions:These results indicated that PPKK moderated the increase in PBG and enhanced glucose metabolism.Trial registration: UMIN-CTR: UMIN000042445 and UMIN000045341Foundation: Mainichiegao Co., Ltd.Keywords: postprandial blood glucose, yeast, mulberry, prediabetes, glycemic control