• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.247-253
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• 2014

In the silage quality, the process of fermentation and use of micro-organism as starter cultures are crucial. The present study investigated the effect of homo and heterofermentative lactic acid bacteria as a starter culture strain on the silage quality and its aerobic stability using meta-analysis. Total 19 studies were used in the analysis. According to the strains of lactic acid bacteria used, experimental groups were assigned to heterofermentative (HEL), mixture of hetero and homofermentative (HHO), homofermentative (HOL) and various homofermentative (HOM). In each experimental group, standardized result of the treatment (with inoculant) was compared with the control (without inoculant) using risk ratio calculation method. The effect of experimental group was also compared. Different starter culture strains did not influence on silage pH and propionic acid production. However, lactic acid and acetic acid production were significantly (p<0.05) influenced by the start culture strains. HOM showed the greatest lactic acid production and HEL was the lowest. In contrast, HEL showed the greatest in acetic acid production and HOM and HOL were the lowest. In terms of ammonia nitrogen, HHO produced more (p<0.05) than the rest of the treatment. In crude protein and water soluble carbohydrate contents, there were no significant effects among treatments. Different strain of lactic acid bacteria significantly influenced on the effect of aerobic stability (p<0.05). Use of heterofermentative showed greater aerobic stability and the use of homofermentative lactic acid bacteria.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.410-414
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• 1999

This study was carried out to investigate distribution of homofermentative lactic acid bacteria(LAB) and heterofermentative LAB during kimchi fermentation period. The number of heterofermentative LAB was decreased during the fermentation. The ethanol extracts of Lithospermum erythrorhizon and Sophrora flavescens AITON showed strong antimicrobial activities against both homofermentative LAB and heterofermentative LAB. The extracts of Glycyrrhiza uralensis and Curcuma longa showed stronger antimicrobial activity against hetrofermentative LAB than against homofermentative LAB. the antimicrobial activities of the plant extracts against LAB were accelerated by mixing of two or three kinds.

• Microbiology and Biotechnology Letters
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• v.36 no.3
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• pp.233-239
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• 2008

A new approach to the solubilization of excess activated sludge by the inoculation of lactic acid bacteria was studied to reduce the amount of sludge produced in the activated sludge treatment process. Aerobic microorganism in sludge was lysed in anaerobic condition and the cytoplasmic substance eluted was utilized as a carbon source by lactic acid bacteria. On the basis of sludge solubilization efficiency, Lactobacillus brevis and Leuconostoc mesenteroides subsp mesenteroides were selected the best candidates among five kinds of Lactobacillus sp. and seven kinds of Leuconostoc sp. The sludge solubilization efficiency by heterofermentative lactic acid bacteria was more efficient than that of homofermentative bacteria. Initial value of soluble COD (sCOD) was 1050 mg/L at the initial inoculation time increased to 3070 mg/L (192% solubilization) at 96 h of the incubation time. The inoculation of lactobacillus brevis to the sludge resulted in 2824% increase in sCOD value after 96 h of incubation than the control experiment. Leuconostoc mesenteroides subsp mesenteroides showed 152% increase of solubilization and 30% increase of S-COD/T-COD on 96 h of incubation time. Considering the increase of S-COD by the inoculation of Leuconostoc sp. on 24 h, 10% inoculation of lactic acid bacteria to the sludge was most effective.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.62-70
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• 2011

The antibacterial effects of nine lactic acid bacteria (LAB) against Campylobacter jejuni were investigated by using agar gel diffusion and co-culture assays. Some differences were recorded between the inhibition effects measured with these two methods. Only two LAB, Lb. pentosus CWBI B78 and E. faecium THT, exhibited a clear anti- Campylobacter activity in co-culture assay with dehydrated poultry excreta mixed with ground straw (DPE/GS) as the only growth substrate source. It was observed that the supplementation of such medium with a cellulase A complex (Beldem S.A.) enhanced the antimicrobial effect of both LAB strains. The co-culture medium acidification and the C. jejuni were positively correlated with the cellulase A concentration. The antibacterial effect was characterized by the lactic acid production from the homofermentative E. faecium THT and the lactic and acetic acids production from the heterofermentative Lb. pentosus CWBI B78. The antagonistic properties of LAB strains and enzyme combination could be used in strategies aiming at the reduction of Campylobacter prevalence in the poultry production chain and consequently the risk of human infection.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.8
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• pp.1123-1132
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• 2015

Winter wheat is a suitable crop to be ensiled for animal feed and China has the largest planting area of this crop in the world. During the ensiling process, lactic acid bacteria (LAB) play the most important role in the fermentation. We investigated the natural population of LAB in whole-crop wheat (WCW) and examined the quality of whole-crop wheat silage (WCWS) with and without LAB inoculants. Two Lactobacillus plantarum subsp. plantarum strains, Zhengzhou University 1 (ZZU 1) selected from corn and forage and grass 1 (FG 1) from a commercial inoculant, were used as additives. The silages inoculated with LAB strains (ZZU 1 and FG 1) were better preserved than the control, with lower pH values (3.5 and 3.6, respectively) (p<0.05) and higher contents of lactic acid (37.5 and 34.0 g/kg of fresh matter (FM), respectively) (p<0.05) than the control. Sixty LAB strains were isolated from fresh material and WCWS without any LAB inoculation. These LAB strains were divided into the following four genera and six species based on their phenotypic, biochemical and phylogenetic characteristics: Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, Lactococcus lactis subsp. lactis, Lactobacillus buchneri, and Lactobacillus plantarum subsp. plantarum. However, the prevalent LAB, which was predominantly heterofermentative (66.7%), consisted of Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, and Lactobacillus buchneri. This study revealed that most of isolated LAB strains from control WCWS were heterofermentative and could not grow well at low pH condition; the selective inoculants of Lactobacillus strains, especially ZZU 1, could improve WCWS quality significantly.

• Food Science and Preservation
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• v.9 no.3
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• pp.292-297
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• 2002

This studies were carried out to investigate the effect of Prunus mume Sie. extract on growth of lactic acid bacteria isolated from kimchi and preservation of kimchi. Prunus mums Sie. extract inhibited the growth of homofermentative lactic acid bacteria and heterofermentative lactic acid bacteria isolated from kimchi. In early storage stage, the pH of Prunus mume Sie. extract added kimchi(PEAK) was lower than that of control. The pH of PEAK was higher than that of control after 25 days of fermentation. Titratable acidity, viable cell of total bacteria and lactic acid bacteria of the PEAK were lower than that of control during fermentation. The sensory quality of 1% PEAK was similar to control at 10 days of fermentation But overall acceptability of 3% PEAK decreased compare with l% PEAK.

• Korean Journal of Microbiology
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• v.52 no.4
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• pp.471-481
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• 2016

The primary objective of this study was to investigate the effects of the bacteriocin-producing heterofermentative lactic acid bacteria (LAB) and acid-resistant yeast isolated from Mukeunji, a Korean ripened kimchi on shelf-life extension and quality improvement of sourdough. According to gene sequence analysis the heterofermentative LAB that showed the antimicrobial activity against bread-spoilage Bacillus strains were identified as Leuconostoc mesenteroides LAS112, Lactobacillus brevis LAS129, and L. mesenteroides subsp. dextranicum LAB137. In addition, the yeasts that were able to grow at acidic pH were identified as Pichia membranifaciens YS05, Pichia fermentans YS19, and Pichia anomala YS26. During sourdough fermentation the levels of acetic acid and bacteriocin produced by L. brevis LAS129 strain were higher than those of L. mesenteroides LAS112 and L. mesenteroides subsp. dextranicum LAS 137 strains, whereas LAS112 strain produced the highest levels of lactic acid. The maximum bacteriocin activity (640 AU/g) against Bacillus subtilis ATCC 35421 was obtained in sourdough fermented by mixed culture of L. brevis LAS129 and P. membranifaciens YS05 or P. anomala YS26. After 24 h of fermentation at $30^{\circ}C$, the viable cell counts of LAS129 ($10^9CFU/g$) in sourdough were higher than those of the YS05 or YS26 ($10^7CFU/g$). Meanwhile, the viable cells of bread-spoilage strain in sourdough fermented with these strains were significantly (P < 0.05) lower than the control group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.359-364
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• 1999

The studies were carried out to investigate antimicrobial activity of mixed extracts of Lithospermum erythrorhizon and Scutellaria baicalensis G. and crab shell against lactic acid bacteria isolated from kimchi. The effects of Lithospermum erythrorhizon and Scutellaria baicalensis G. extracts and crab shell on shelf life of kimchi were also investigated. The growth of heterofermentative and homofer mentative lactic acid bacteria was inhibited by 95% ethanol extracts of Lithospermum erythrorhizon and Scutellaria baicalensis G. The pH of kimchi containing 1% of mixed extracts Lithospermum erythrorhizon. and Scutellaria baicalensis G., and crab shell was lower than control during fermentation for 25 days of 10oC. The viable cells of the kimchi samples were lower than that of control during fermentation. The sensory qualities of the kimchi samples were a little inferior to the control during shelf life of kimchi.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.404-409
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• 1999

The studies were carried out to investigate antimicrobial activity of mixture of Caesalpina sappan L. and Lithospermum erythrorhizon extracts against lactic acid bacteria isolated from Kimchi. The effects of the mixture and crab shell extracts on the shelf-life of Kimchi were also investigated. The growth of heterofermentative lactic acid bacteria and homofermentative lactic acid bacteria was inhibited by 98% ethanol extracts of Caesalpina sappan L. and Lithospermum erythrorhizon. The pH of Kimchi containing mixed extracts of Caesalpina sappan L. and Lithospermum erythrorhizon extracts (1 : 1) and crab shell was lower than that of control during fermentation for 25 days of $10^{\circ}C$. The viable cells of Lactic acid bacteria of the mixed extracts and crab shell added Kimchi were lower than that of control during fermentation. The sensory quality of the mixed extracts and Crab shell added Kimchi was a little inferior to control for during fermentation of Kimchi.

• Journal of Microbiology and Biotechnology
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• v.5 no.6
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• pp.309-314
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• 1995

Samples were collected from a commercial ethanol production plant to enumerate the bacterial contamination in each step of a starch based ethanol production process. Though the slurry of raw material used in the process carried bacteria with various colony morphology in the order of $10^4$ per ml, only the colonies of white and circular form survived and propagated through the processes to the order of $10^8$ per ml at the end of fermentation. Almost all of the bacterial isolates from the fermentation broth were lactic acid bacteria. Heterofermentative Lactobacillus fermentum and L. salivarius, and a facultatively heterofermentative L. casei were major bacteria of an ethanol fermentation. In a batch fermentation L. fermentum was more detrimental than L. casei to ethanol fermentation. In a cell-recycled fermentation, ethanol productivity of 5.72 g $I^{-1} h^{-1}$ was obtained when the culture was contaminated by L. fermentum, whilst that of the pure culture was 9.00 g $1^{-1} h^{-1}$. Similar effects were observed in a cell-recycled ethanol fermentation inoculated by fermentation broth collected from an industrial plant, which showed a bacterial contamination at the level of 10$^8$ cells per ml.