Comparison of Microbial Diversity of Korean Commercial Makgeolli Showing High ß-Glucan Content and High Antihypertensive Activity, Respectively.

We measured physiological functionalities, including antihypertensive angiotensin I-converting enzyme inhibitory activity and immun-stimulating ß-glucan content for sixty kinds of Makgeolli that is commercially available from the market. As a result, we selected R-12 commercial raw Makgeolli, with a high content of immuno-stimulating ß-glucan, and R-14 commercial raw Makgeolli, exhibiting high antihypertensive activity. Due to the similarities in their overall physicochemical properties and raw materials used for fermentation, we compared the microbial flora in order to investigate the reason for the differences in their functionalities. Nested PCR and denaturing gradient gel electrophoresis for yeasts and bacteria were performed for analysis of microbial diversity of two different kinds of Makgeolli (i.e., R-12, R-14), which showed immuno-stimulating ß-glucan content and exhibited a very high level of antihypertensive activity, respectively. Analysis of the 18S rDNA amplicon revealed a major presence of the yeast strain Pichia burtonii in every Makgeolli sample. Analysis of the 16S rDNA amplicon revealed a predominance of lactic acid bacteria, and the most frequent lactic acid bacteria were Lactobacillus ingluviei, L. fermentum, and L. harbinensis, and Lactobacillus sp. Among these, L. harbinensis was detected only in R-12 and L. ingluviei was found only in R-14. Different functionalities from the individual commercially available Makgeolli may be attributed to actions of different microbial flora during fermentation.

Effect of Ganoderma lucidum on the quality and functionality of Korean traditional rice wine, yakju.

The goal of this study was to develop a high value Korean traditional rice wine possessing the pharmaceutical functionality of Ganoderma lucidum. The effects of the fruiting body of G. lucidum on the alcohol fermentation of Korean traditional rice wine, yakju, were investigated. Optimal fermentation conditions for the preparation of G. lucidum-yakju consisted of the koji added at 15% and a fermentation period of 15 d at 25 degrees C. The effects of the amount of G. lucidum added on the acceptability and functionality of G. lucidum-yakju were investigated. G. lucidum GL-1 yakju brewed by adding 0.1% G. lucidum into the mash showed the best acceptability and its angiotensin I-converting enzyme (ACE) inhibitory activity and SOD-like activity were 63% and 42%, respectively, both of which are higher than those of yakju. The high ACE inhibitory activity of G. lucidum GL-1 yakju was found to result from ganoderic acid K in G. lucidum on the basis of physical and spectral data. However, the fibrinolytic activity and antioxidant activity of G. lucidum GL-1 yakju were very low, while tyrosinase inhibitory activity was not determined. From these results, G. lucidum GL-1 yakju may become a new functional Korean traditional rice wine with antihypertensive properties.