牛瘤胃中琥珀酸产生菌的分离鉴定研究

Screening and identification of the succinic acid-producing bacterium from bovine rumen

通过添加地克球利进行富集培养,结合溴甲酚绿中性平板从牛瘤胃中初步筛选得300株产酸菌,TLC法点样分离出31株菌有不同程度的琥珀酸生产能力,进一步地HPLC法定性定量,复筛得8株发酵性状较优菌株,其中最有潜力的一株菌NO.4发酵琥珀酸累积产量达16.8 g/L。针对菌株的细胞及菌落形态研究表明,菌落为圆形凸起,表面光滑,不透明或半透明,呈浅兰色或乳白色,边缘整齐,菌体呈球状,细胞大多数单个或成双甚至成串出现,菌体兼性厌氧,呈革兰氏阳性,无内生芽孢,有荚膜,可运动。对菌株的进一步生理生化和16s-rRNA分析确认为Leuconostoc mesenteroides,最终将菌株NO.4命名为L.mesenteroides JST。

Dikezhuli was added into the enrichment medium at the primary step, and about 300 strains were gained from bovine rumen with the bromocresol green medium as the selective mark. Then 31 strains were selected at the following period with the TLC method by the appearance of the succinic acid spot in the plate. Eight high yield strains were gained with the HPLC analysis method. The potential strain was the strain NO. 4 and its succinic acid yield was 16.8 g/L. The individual cell and colonies morphologic characteristics of the strain NO. 4 were studied. Surface colonies are orbicular, smooth,convex, translucent or opaque and light blue or milk white in colour. Arrangement of cells is as singles, dilops, and clumps. It is facultatively anaerobic, Gram-positive, motile and non-spore-forming. Further API tests and 16s-rRNA sequence analysis indicate that this strain belongs to Leuconos- toc mesenteroides genus and has been named L. mesenteroides JST.