Aim To isolate, screen and identify the lactic acid bacteria (LAB) from elephant silage during the process of the fermentation and their effects on the fermentation quality of sweet sorghum silage. Methods and Results The isolated strains were identified based on morphological, physiological and biochemical characteristics as well as 16S rRNA analysis. Seven LAB strains were isolated from elephant grass silage. Three strains (Pediococcus acidilactici (AZZ1), Lactobacillus plantarum subsp. plantarum (AZZ4), L. plantarum subsp. argentoratensis (AZZ7) and one commercial bacteria L. plantarum, ecosyl MTD/1(CB)) were chosen as additives at 6 log colony forming units per gram of fresh sweet sorghum grass in laboratory silos (680 g). Silos for each treatment were opened after 5, 7, 14, 30 and 60 days, respectively. All isolates were characterized as Gram‐positive, catalase‐negative and grow normally in 6·5% NaCl. The strains AZZ1, AZZ2 and AZZ5, were identified as Pediococcus genus while AZZ3, AZZ4, AZZ6 and AZZ7 were Lactobacillus genus. Compared to the control, all the isolates improved the silage quality of sweet sorghum silage, indicated by significantly (P < 0·05) lower pH and ammonia‐nitrogen contents and undesirable micro‐organism counts, and higher lactic acid (LA) contents and ratios of lactic acid/acetic acid. During ensiling, AZZ4 performed better among all of inoculants, indicated by significantly (P < 0·05) decreased on pH and ammonia‐N contents and higher increased on LA contents. Conclusion Strain AZZ4 is recommended as starter culture for sweet sorghum. Significance and Impact of the Study This is the first time to investigate the effects of LAB isolates from elephant grass silage and use them as additives, which is to find out how LAB inoculants improve the fermentation quality of sweet sorghum silage.

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How to Cite This ArticleSifeeldein A, Yuan X, Dong Z, Li J, Shao T: Effect of applying Lactobacillus plantarum and Pediococcus acidilactici Isolated on fermentation dynamics, microbial community and aerobic stability of napier grass (Pennisetum purpureum) silage. Kafkas Univ Vet Fak Derg, 24 (3): 371-378, 2018. DOI: 10.9775/kvfd.2017 AbstractThe aim of this study was to determine the effect of applying three of lactic acid bacteria isolates AZZ1, AZZ4, AZZ7 and one commercial (CB) on the fermentation dynamics, microbial community and aerobic stability of Napier grass silage. The grass was ensiled with or without the addition of a lactic acid bacteria inoculant at 1.0×106 CFU/g of fresh material to Napier grass silage. Napier grass was ensiled in laboratory silos and treated as follows: no additives (control), Pediococcus acidilactici (AZZ1), Lactobacillus plantarum subsp. plantarum (AZZ4), Lactobacillus plantarum subsp. argentoratensis (AZZ7) and Lactobacillus plantarum, Ecosyl MTD/1 (CB). To follow the fermentation dynamics during ensiling samples were taken on days 7, 14, 30, 60 and 90 of ensiling for chemical and microbiological analysis. Aerobic stability was determined on day 90 of ensiling. The experimental design was a completely randomized design, with a 5 × 5 × 3. The inoculant resulted in a more decreased (P<0.0001) in pH, water soluble carbohydrate, ammonia nitrogen, organic acid, aerobic bacteria and yeast, while a higher (P<0.0001) level of lactic acid content and lactic acid bacteria compared with control group. Treatment with AZZ4 had the better (P<0.0001) fermentation results. The aerobic stability of Napier silage was reduced with strains treatment compared with the control. In conclusion, the addition of bacteria inoculant resulted in better preservation and reduced the aerobic stability of silage.

The purpose of this study is to isolate and identify lactic acid bacteria from elephant grass (Pennisetum purpureum) silage and examine their effect on the silage fermentation quality. Three of lactic acid bacteria strains were isolated from elephant silage and their characterization, identification, and influence on silage quality after 90 d of ensiling was studied. All three strains were Gram-positive, catalase-negative, and were grown in 6.5% NaCl and pH 4.00. Strains AZZ1, was identified as for genus pediococcus, whereas, AZZ4 and AZZ7 strains were classified as genus Lactobacillus according to the phenotype, 16S rRNA, and RecA gene analysis. Three strains were used as additives at 1.0×106 CFU/g of fresh material of elephant grass. Strain AZZ4 is found to be the most effective in improving the fermentation quality of the elephant grass silage, as indicated by a lower (P<0.0001) dry matter losses, pH value, water-soluble carbohydrates, acetic acid content, butyric acid, propionic acid and ammonia-N. However, the lactic acid content was higher (P<0.0001) compared to the control and other treatments. In conclusion, these results suggest that, for well-preserved silage, the isolates may be useful as inoculants for silage making, and could play a major role in developing silage production.