JPH03285675A - New lactobacillus - Google Patents

Abstract

PURPOSE:To surely accelerate the lactic acid fermentation immediately after the start of fermentation by using Lactobacillus KB-473 strain having specific mycological properties such as asporous and Gram-positive nature. CONSTITUTION:Lactobacillus KB-473 (FERM P-10476) which is a lactic bacteria belonging to genus Lactobacillus and having specific mycological properties such as asporous nature and homo-type brevi-form Gram-positive bacteria can rapidly accumulate a large amount of lactic acid in aerobic condition as well as in anaerobic condition. The lactic acid accumulation rate of the strain the higher than that of standard strain. The pH of the medium is lowered by the produced lactic acid. When the strain is used in the lactic acid fermentation of silage, etc., the proliferation of putrefying bacteria can be suppressed at the initial stage of preparation. Accordingly, the subject lactobacillus is effective in preventing the deterioration of the taste of silage, etc., caused by the substance formed by the putrefying bacteria. The present lactobacillus is extremely useful for the stable preparation of a high-quality silage, fermented sausage, pickles, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a novel lactic acid bacterium belonging to the genus Lactobacillus and mainly used in the preparation of silage-fermented sausages, pickles, etc.

[Conventional technology]

The preparation of silage, etc. mentioned above all have in common that it is required to secure a large amount of lactic acid accumulation from the early stage of fermentation. Silage is produced by harvesting grass, etc. and storing it in silos and fermenting it mainly in anaerobic conditions.

[Problem to be solved by the invention]

However, immediately after silage raw materials such as grass are harvested, they are exposed to the air, resulting in an aerobic atmosphere, making it impossible to carry out the desired anaerobic fermentation from the beginning. Therefore, in order to be used as feed for livestock, the respiration of the cut feed itself must progress and the oxygen between the stacked raw materials must be sufficiently consumed to reach an anaerobic atmosphere. It took a considerable amount of time for anaerobic fermentation to proceed. In such cases, aerobic bacteria with strong reproductive capacity may proliferate by the time the silage raw material reaches an anaerobic atmosphere, and the growth of lactic acid bacteria may be delayed.

In addition, even if an anaerobic atmosphere is reached, the number of viable aerobic bacteria does not decrease rapidly, and while the growth of lactic acid bacteria does not proceed smoothly, bacteria such as butyric acid bacteria, which emit an odor that livestock do not like, Putrefaction bacteria sometimes proliferate before lactic acid bacteria, and it has not always been possible to achieve good anaerobic fermentation.

Therefore, the present invention solves the above-mentioned problems of the conventional technology, and provides a highly nutritious and delicious flavor that livestock and humans like from the start of fermentation for silage raw materials such as grass, while suppressing the growth of other bacteria. The purpose of the present invention is to provide a novel lactic acid bacterium that reliably promotes lactic acid fermentation that gives .

[Means to solve the problem]

In order to achieve the above object, the novel lactic acid bacteria according to the present invention are characterized by the fact that they belong to the genus Lactobacillus, do not produce spores, and are homozygous Gram stain-positive short rods. Lactobacillus KB-4 has the following characteristics and has the ability to accumulate lactic acid quickly after the start of fermentation.
73 strain (Feikoken Bibori No. 10476).

[Action/Effect]

The present inventors have made extensive efforts to discover lactic acid bacteria that actively promote lactic acid fermentation from the early stages of storage of silage raw materials. We succeeded in finding a bacterium that has a sufficient ability to accumulate lactic acid, especially in the early stages of fermentation.

The lactic acid bacterium according to the present invention, Lactobacillus KB473 strain, has the following properties.

Medium: LCM (Lactohacillus cassomedium) medium pH: 6.8, showing good growth when cultured at 37°C for 124 hours.

Short bacillus spores None Gram staining Positive Physiological properties Lactic acid fermentation Homomorphic catalase None Suitable growth temperature 30-35°C Growth temperature 15-40°C Sugar assimilation (For this, see Hokkaido University Department of Applied Mycology Conservation) Table 1 shows the results of comparison with the Lactobacillus plantarum standard strain. + + ± 1, -arabinose'' - Repose + ±rhamnose
± Ethanol Glycerol Erythritol Galactitol Mannitol α-Me-Glycoside Salicin + + Inositol Citrate Mannose + + Regarding the assimilation of the above sugars, BTB was added to the basic medium with the following composition and sterilized for 121°CCl2O minutes. After cooling, each saccharide was added at a concentration of 2%, and then a suspension of lactic acid bacteria was inoculated drop by drop and cultured at 30°C for investigation.

After 7 days of culture, as a result of proliferation, the color of the medium changed from green to yellow, which was judged to be assimilable.

Basic medium polypeptone 0.5% yeast extract
0.5% dipotassium phosphate 0.5% or more From the results of 2, it is clear that the lactic acid bacteria of the present invention belong to the genus Lactobacillus, and Lactobacillus branfrum A++j+=1526 (hereinafter abbreviated as 17. branfrum) ) is recognized as a similar fungal species. However, 17. Branflume differs in its ability to assimilate the sugars sorbose, trehalose, raffinose, scootchi, L-arabinose, ribose, and rhamnose, and as detailed in the examples, it can be grown in either aerobic or anaerobic conditions at the initial stage of culture. suddenly in the atmosphere of
It is recognized that rapid and large amounts of lactic acid accumulate. 1, whose lactic acid accumulation rate is the standard strain.

Compared to Branflume, the KB-473 of the present invention requires approximately 2 lbs. to accumulate the same amount of lactic acid under both aerobic and anaerobic conditions.
It is observed that each test is performed 4 hours faster (see Table 4).

In the lactic acid fermentation of the above-mentioned silage, etc., after the pi drops to around 4, the growth of bacteria including lactic acid bacteria is inhibited and a stable state is reached, which suppresses the growth of spoilage bacteria in the early stage of fermentation, and the substances produced by these spoilage bacteria. It is a crucial element to prevent the taste of silage, fermented sausage, etc. from deteriorating due to this. Therefore, as described in Section 2, the accumulation of lactic acid and the concomitant drop in pl+ occur approximately 24 hours earlier than in the standard strain, and the rapid drop in pl+ inhibits the growth of other spoilage bacteria in the early stages of fermentation. As a result, the KB-473 of the present invention, which can effectively suppress the effects of oxidation, can supply silage, etc., which is the final product of lactic acid fermentation, in a high-quality state. Moreover, as shown in FIG. 2 and Table 3 of Examples, KB-473 of the present invention can be used even under aerobic conditions with 1 standard strain.
7. Plantarum, which causes lactic acid accumulation and pH drop more quickly, and even if the transition from aerobic conditions to anaerobic conditions is delayed, the pH drop due to lactic acid accumulation will occur, so the growth of other aerobic bacteria will be sufficient. silage etc. can be prepared with stable quality.

The present bacterial strain, Uctobacillus Kn-473, has been deposited at the Institute of Microbial Technology, Agency of Industrial Science and Technology as Microbiological Research Institute No. 10476.

〔Example〕

Next, the specific lactic acid production ability of this strain will be explained based on experimental results.

[Experimental example 1] Lactic acid accumulation amount (%) of sugars with assimilability
Measurement of the amount of lactic acid accumulated in Table 1 above was further measured for the sugars that were found to be assimilated by both KB-473, the standard strain, and Branfrum. Add 2.0% sugar to the above basic medium at 30°C.
The amount of lactic acid accumulated was measured after 48 hours and 96 hours of culture.

The results are shown in Table 2.

Table 2 *L:L, Blankrum These results confirmed that KB-473 of the present invention is a standard strain for all of the above sugars, and that it has a greater ability to assimilate sugars than Branfrum.

[Experimental Example 2] Comparison of growth performance The above basic medium contains 2.0% glycose and 0 calcium carbonate.
．． The number of viable bacteria was determined by the usual dilution plate culture method using a medium containing 5% agar and 1.3% agar. The results are shown in Figure 1.

From this result, KB-473 of the present invention is a standard strain.

The initial growth rate is higher than Branfrum, and even the number of viable bacteria under pl+4.0, which suppresses the growth of lactic acid bacteria, is p.
20°C, which is the normal condition in steady state after H reduction.
It was confirmed that the strain was superior to the standard strain at 30°C and 30°C.

[Experimental Example 3] Comparison of lactic acid accumulation (%) and pH 2.0% glucose was added to the basic medium, inoculated with KB473, Branfrum, and incubated at temperatures of 20°, 30°, and 37°C over time. The amount of lactic acid accumulated was measured.

The amount of lactic acid accumulated was measured using a titration method and calculated using the following formula.

Lactic acid amount - N/10 Sodium hydroxide titration number x fx0.0
The measurement results of 09xlOO/sample amount are shown in Table 3, and the time-dependent changes in pl+ and lactic acid amount at 30°C are shown in FIG.

Table 3 L: Branhulme 1 2 From this result, KB-473 of the present invention is a standard strain.

pH at which the growth of lactic acid bacteria itself is inhibited more than that of branfrum
It was confirmed that lactic acid was rapidly accumulated until the pH reached around 4, lowering the pH. This early drop in pi+ is the optimum pH.
It is advantageous in suppressing the growth of many bacteria around 7.

[Experimental Example 4] Relationship between lactic acid production and oxygen 2.0% glucose was added to the basal medium, three strains of lactic acid bacteria were inoculated, and aerobic static culture and anaerobic culture (manufactured by BBL) were carried out at 30°C. (in an anaerobic jar) static culture was performed. The results are shown in Table 4 and FIG.

Table 4 □□1 From the above results, it was confirmed that KB-473 accumulates lactic acid more rapidly than the standard strain Branfrum under both aerobic and anaerobic conditions.

(Experimental Example 5) The culture conditions were set as shown in (1) to (2) below, and the culture characteristics of the standard strain Branfrum and KB-473 were compared.

■ Medium: PYG (polypeptone yeast glucose) medium ■ Culture temperature: 30°C ■ Culture time Near 2 hours The results are shown in Table 5.

Table 5 Tatami From the above results, it was quantitatively confirmed that KB-473 produced more lactic acid and grew faster than the standard strain.

3 4 4 As is clear from the results in section 2, the lactic acid bacteria K according to the present invention
B-473 has the excellent property of rapidly accumulating a large amount of lactic acid and causing a concomitant pH drop from the beginning of fermentation. It is extremely advantageous to do so. Although KR-473 of the present invention can be used alone, it may also be used in combination with other lactic acid bacteria having different properties. Furthermore, KB-473 of the present invention is also useful in the production of foods such as lactic acid bacteria drinks and yogurt.

[Brief explanation of drawings]

Figure 1 (A), (II), and (C) are at 20'C and 130°C.
A diagram showing the change in the number of viable bacteria at each temperature of 137°C.
FIG. 3 is a diagram showing changes in the amount of lactic acid and pH in a culture medium at various temperatures of 7°C.

Claims (1)

[Claims] Lactobacillus is a lactic acid bacterium belonging to the genus Lactobacillus, which has the biological characteristics of not producing spores and being a homozygous Gram-staining positive short bacillus, and has the ability to accumulate lactic acid quickly after the start of fermentation. A novel lactic acid bacterium characterized by being the KB-473 strain (Feikoken Bacteria No. 10476).