title: Natural populations of lactic acid bacteria associated with silage fermentation as determined by phenotype, 16S ribosomal RNA and recA gene analysis.
abstract: One hundred and fifty-six strains isolated from corn (Zea mays L.), forage paddy rice (Oryza sativa L.), sorghum (Sorghum bicolor L.) and alfalfa (Medicago sativa L.) silages prepared on dairy farms were screened, of which 110 isolates were considered to be lactic acid bacteria (LAB) according to their Gram-positive and catalase-negative characteristics and, mainly, the lactic acid metabolic products. These isolates were divided into eight groups (A-H) based on the following properties: morphological and biochemical characteristics, γ-aminobutyric acid production capacity, and 16S rRNA gene sequences. They were identified as Weissella cibaria (36.4%), Weissella confusa (9.1%), Leuconostoc citreum (5.3%), Leuconostoc lactis (4.9%), Leuconostoc pseudomesenteroides (8.0%), Lactococcus lactis subsp. lactis (4.5%), Lactobacillus paraplantarum (4.5%) and Lactobacillus plantarum (27.3%). W. cibaria and W. confusa were mainly present in corn silages, and L. plantarum was dominant on sorghum and forage paddy rice silages, while L. pseudomesenteroides, L. plantarum and L. paraplantarum were the dominant species in alfalfa silage. The corn, sorghum and forage paddy rice silages were well preserved with lower pH values and ammonia-N concentrations, but had higher lactic acid content, while the alfalfa silage had relatively poor quality with higher pH values and ammonia-N concentrations, and lower lactic acid content. The present study confirmed the diversity of LAB species inhabiting silages. It showed that the differing natural populations of LAB on these silages might influence fermentation quality. These results will enable future research on the relationship between LAB species and silage fermentation quality, and will enhance the screening of appropriate inoculants aimed at improving such quality.
authors.affiliation: National Institute of Livestock and Grassland Science, Nasushiobara 329-2793, Japan.
authors.forename: Huili
authors.initials: H
authors.lastname: Pang
authors.forename: Guangyong
authors.initials: G
authors.lastname: Qin
authors.forename: Zhongfang
authors.initials: Z
authors.lastname: Tan
authors.forename: Zongwei
authors.initials: Z
authors.lastname: Li
authors.forename: Yanping
authors.initials: Y
authors.lastname: Wang
authors.forename: Yimin
authors.initials: Y
authors.lastname: Cai
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D001647:Bile Acids and Salts / Q000378:metabolism; D044822:Biodiversity; D005285:Fermentation; D019344:Lactic Acid / Q000378:metabolism; D056546:Lactobacillales / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D000455:Medicago sativa / Q000378:metabolism / Q000382:microbiology*; D008969:Molecular Sequence Data; D012275:Oryza / Q000378:metabolism / Q000382:microbiology*; D010641:Phenotype; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D011938:Rec A Recombinases / Q000235:genetics; D017422:Sequence Analysis, DNA; D012820:Silage / Q000032:analysis / Q000382:microbiology*; D045868:Sorghum / Q000378:metabolism / Q000382:microbiology*; D003313:Zea mays / Q000378:metabolism / Q000382:microbiology*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D001647:Bile Acids and Salts; D012336:RNA, Ribosomal, 16S; D019344:Lactic Acid; D005680:gamma-Aminobutyric Acid; D011938:Rec A Recombinases