为筛选调制优质动物苜蓿青贮饲料的优良乳酸菌，本试验以从郑州地区9个苜蓿样品中分离得到的乳酸菌为试验材料，经抗菌活性、生长特性及产酸特性筛选菌株，根据16S rDNA序列，结合生理生化特征进行菌种鉴定，并通过发酵苜蓿粉考察菌株的发酵特性。结果表明，从分离的19株乳酸菌中筛选到4株具有高抗菌活性的菌株，其中菌株ZZU 457和ZZU 466在MRS液体培养基中生长及产酸性能较好，均能够耐受6.5%的盐浓度环境；菌株ZZU 457耐受10~45℃，以及pH为3.5的环境，而菌株ZZU 466能够耐受5~50℃，以及pH为4.0的环境；苜蓿粉发酵结果表明接种ZZU 457或ZZU 466在发酵18 h内均能快速产酸，其中接种ZZU 466的苜蓿粉发酵36 h时pH值达到4.2；结合理化特征及16S rRNA序列分析结果，ZZU 466被鉴定为融合魏斯氏菌。优良菌株ZZU 466在苜蓿青贮饲料调制加工中具有潜在的应用价值。%The purpose of this research was to screen high quality lactic acid bacterias for alfalfa silage.9 alfalfa sam-ples of Zhengzhou area were selected by comparing of their antimicrobial activity or growth features and acid production features.Stains of the ideal samples were identified according to the sequence of 16S rDNA and the physiological and bio-chemical characteristics.The fermentation features of alfalfa meal for the excellent strains were also studied.We got 4 lactic acid bacterias that performed a higher activity to inhibit of indicator bacterias.Only ZZU 457 and ZZU 466 of 4 strains showed high rate of growth and acidification in MRS liquids.ZZU 457 could tolerant temperature of 10 ~ 4.5 ℃ and low pH environment(pH 3.5).Strain of ZZU 466 could survive in temperature of 5~50 ℃and low pH environment(pH 4.0). Results of the alfalfa meal fermentation indicated that both two strains could produce acid quickly within 18 hours ,espe-cially for strains of ZZU 466.It could reduce the pH to the lowest value of 4.2 for the alfalfa meal fermentation liquids at 36 hours.According to the physiological and biochemical test,analysis of the 16S rRNA sequence identified that this strains was W.corfusa.The strain of ZZU 466 had potential value of application as an additive in alfalfa silage.
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