γ-聚谷氨酸合成菌的鉴定及其对肥效的影响

Identification of γ-polyglutamic Acid Producing Strain and Its Effects on Fertilizer Efficiency

从豆豉中分离到1株产γ-聚谷氨酸（γ-polyglutamic acid,γ-PGA）的菌株JG,通过菌株形态特征和16S rDNA序列对比分析,对该菌株进行了鉴定。同时对发酵产物进行了提纯,并添加不同比例聚谷氨酸到复合肥中,进行盆栽试验。结果表明,该菌株16S rDNA序列与Bacillus subtilis HQ 327126的同源性达到99%,确定该菌株为枯草芽孢杆菌（Bacillus subtilis）。该菌株γ-PGA的发酵产量为40 g/L,对发酵产物进行提纯,获得含量为80%的γ-PGA。添加不同浓度γ-PGA的处理,芜青油菜叶绿素含量明显提高,添加0.02%-0.03%的γ-PGA,芜青油菜鲜重增加可达18.35%-19.57%,具有明显提高肥效的作用。

Abatract： One γ-polyglutamic acid（γ-PGA） producing strain JG was isolated using the conventional methods. The strain was identified through morphological and sequence contrastive analysis of 16 S rDNA. The fermenting product was purified and added into the compound fertilizer by different proportion to carry on the pot planting experiment. The results showed that,the homelogy of 16 S rDNA Sequence of this strain with Bacillus subtilis（HQ327126） reached 99%,thus strain JG was identified as Bacillus subtilis. The yield of γ-PGA was 40 g / L. The fermenting product was purified,and γ-PGA content of 80% was obtained. The adding of γ-PGA has the best effect on increasing the chlorophyll content of Brassica chinensis. Addition of0.02%-0.03% γ-PGA,fresh weight of Brassica chinensis increased by 18.35%-19.57%. γ-PGA added to compound fertilizer could obviously improve the efficiency of the role.