著者

原 昌道 水野 昭博

出版者

公益社団法人日本生物工学会

雑誌

醗酵工学会誌 : hakkokogaku kaishi (ISSN:03856151)

巻号頁・発行日

vol.59, no.1, pp.17-22, 1981-01-25

被引用文献数

1

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Most of the lactate formed by malo-lactic fermentation (MLF) during storage of the red wines produced at our Institute was the L(+)-isomer. From these MLF wines, a malo-lactic bacterium which produced mainly D-lactate from glucose by lactic acid fermentation was isolated and classified as Leuconostoc mesenteroides. The production of L-or D-lactate from L-malate was examined in the isolated MLF bacterium (MLB-S-6 strain) and the culture strains Leuc. mesenteroides IAM 1233,Lactobacillus casei IAM 1118,Lactobacillus plantarum IAM 1216,Lactobacillus arabinosus IAM 1041,and Streptococcus lactis RIB 806. All of the tested strains preadapted to malic acid converted L-malate to L-lactate within the range of pH 3.2-7.0. the optimal pH was 4-5 and the reaction was not inhibited by semicarbazide. On the other hand, D-lactate and acetate were produced from L-malate at higher pH, though generally much less D-lactate was formed than L-lactate. Leuc. mesenteroides also converted pyruvate to D-lactate and acetate whthin the range of pH 5-7. The optimal pH was 6.0 and the reaction was completely inhibited by semicarbazide (2,000ppm). A cell-free extract of Leuc. mesenteroides strain (MLB-S-6,IAM 1233) converted L-malate to L-lactate in the presence of NAD, Mn^〓 and semicarbazide. The specific activities were higher than those of the other tested strains. These results suggest than L-lactate in the wine was formed mainly from L-malate by malo-lactic enzyme, which directly converted L-malate to L-lactate. D-or L-lactate migth also in part be formed via pyruvate by the consecutive action of malic enzyme and D- or L-lactate dehydrogenase, especially in wine of high pH or when undesirable lactic aicd bacteria grow in the wine.