Novel lactic acid bacterium

Abstract

This invention provides lactic acid bacteria that have one or more effects selected from among fatigue-ameliorating effect, blood circulation-improving effect, stool odor-reducing effect, and growth-promoting effect and that can be used with high safety. This invention further provides a pharmaceutical preparation comprising, as an active ingredient, lactic acid bacteria that have one or more effects selected from among fatigue-ameliorating effect, blood circulation-improving effect, stool odor-reducing effect, and growth-promoting effect. According to the invention, novel lactic acid bacteria belonging to the Enterococcus faecium species having particular mycological properties and exhibiting viability of 40% or higher when freeze-dried in the absence of a dispersion medium and viability of 80% or higher in a probiotic preparation when stored at 40° C. for 4 months, a composition comprising such lactic acid bacteria, an agent for ameliorating fatigue, improving blood circulation, reducing stool odor or promoting growth comprising, as an active ingredient, such composition, and use of such composition for food and other products.

1 . Lactic acid bacteria belonging to the  Enterococcus faecium  species having the mycological properties described below and exhibiting viability of 40% or higher when freeze-dried in the absence of a dispersion medium and viability of 80% or higher in a probiotic preparation when stored at 40° C. for 4 months:
 morphologic properties 
 1) gram stain: positive 
 2) sporulation potential: none 
 3) motility: none 
 physiological properties 
 1) catalase: negative 
 2) sodium pyruvate degradation: positive 
 3) esculin hydrolysis: positive 
 4) pyrrolidonyl-2-naphthylamide degradation: positive 
 5) 2-naphthyl-β-D-galactopyranoside degradation: positive 
 6) L-leucine-2-naphthylamide degradation: positive 
 7) L-alginic acid degradation: positive 
 8) degradability of various carbohydrates
 D-ribose: + 
 D-mannitol: + 
 lactose: + 
 D-sorbitol: − 
 D-trehalose: − 
 D-raffinose: − 
 
 
     
     
         2 . The lactic acid bacteria belonging to the  Enterococcus faecium  species according to  claim 1  having the chemotaxonomic properties described below:
 the lactic acid bacteria have the nucleotide sequence as shown in SEQ ID NO: 1 or a nucleotide sequence showing 90% or higher sequence identity with SEQ ID NO: 1. 
 
     
     
         3 . The lactic acid bacteria belonging to the  Enterococcus faecium  species according to  claim 1 , which are  Enterococcus faecium  R30 strain (NITE BP-01362),  Enterococcus faecium  R28 strain (NITE BP-01361), or a variant thereof having a DNA mutation. 
     
     
         4 . A composition comprising the lactic acid bacteria according to  claim 1  or a processed product or extraction residue of the lactic acid bacteria. 
     
     
         5 . The composition according to  claim 4 , which further comprises a protective agent. 
     
     
         6 . The composition according to  claim 5 , wherein the content of the protective agent is 1% by weight or more relative to the dry weight of bacteria. 
     
     
         7 . The composition according to  claim 5 , wherein the protective agent is at least one member selected from the group consisting of sucrose, trehalose, sodium glutamate, histidine, and malic acid. 
     
     
         8 . An agent for ameliorating fatigue comprising, as an active ingredient, the composition according to  claim 4 . 
     
     
         9 . An agent for improving blood circulation comprising, as an active ingredient, the composition according to  claim 4 . 
     
     
         10 . An agent for reducing stool odor comprising, as an active ingredient, the composition according to  claim 4 . 
     
     
         11 . An agent for promoting growth comprising, as an active ingredient, the composition according to  claim 4 . 
     
     
         12 . A food product comprising the composition according to  claim 4 . 
     
     
         13 . A feed or veterinary drug comprising the composition according to  claim 4 . 
     
     
         14 . A pharmaceutical product comprising the composition according to  claim 4 . 
     
     
         15 . A method for screening lactic acid bacteria having at least one effect selected from among fatigue-ameliorating effect, blood circulation-improving effect, stool odor-reducing effect, and growth-promoting effect, comprising the following steps:
 (1) freeze-drying a bacterial concentrate of test lactic acid bacteria in the absence of a dispersion medium;   (2) selecting lactic acid bacteria exhibiting viability of 40% or higher when freeze-dried in step (1);   (3) preparing a probiotic preparation comprising freeze-dried bacterial strains obtained by adding a dispersion medium to the lactic acid bacteria selected in step (2), and then freeze-drying the resultant; and   (4) storing the probiotic preparation prepared in step (3) at 40° C. for 4 months, and then selecting lactic acid bacteria exhibiting viability of 80% or higher in the probiotic preparation.