• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.96-101
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• 1992

Two strains of polyvinyl alcohol (PVA) utilizing bacteria were isolated from the waste water and soil. These strains, G5Y and PW, were able to utilize PVA symbiotically as a carbon source, but could not utilize PVA separately. In the mixed culture of these strains, 0.5 percent of PVA was almost completely degraded in 3 days. Effect of degree of PVA polymerization on the its utilization was examined, and there was no remarkable difference among three kind of PVA (PVA 500, 1500, a d 2000). These bacteria were able to utilize PV,4 in the desizing waste water of factory as well as enrichment PVA medium. These strains, C5Y and PW, were identified as Pseudomonas cepucia and Pseudomonus pseudomallei, respectively, based on morpholofical and biological characteristics.

• Microbiology and Biotechnology Letters
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• v.27 no.2
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• pp.172-178
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• 1999

In this study, we tested possibility of replacing nitrite salts, which were always added during the meat product processing, with the metabolites produced by antimicrobial and red pigment producing Monascus strains. We have already shown that Monascus No. 116 strain has the highest antimicrobial activity among the strains isolated from Ang-Khak. Monascus isolate No. 229 was chosen due to its outstanding red pigment producing ability. The red pigment production by No. 229 was highest in the medium containing 8% sucrose, 2% yeast extract, 0.1% K2HPO4, 0.5% MgSO4. Optimum pH and temperature for the red pigment production were pH 6.2 and 3$0^{\circ}C$, was found in spot or Rf value 0.54 on TLC plate using ethyl acetate-acetone-water (4:4:1, v/v/v) as development solvent system. Isolate No. 116 and No. 229 were cultured in a optimal condition for the antimicrobial activity and red pigmentation. The culture concentrates were applied in situ to the production of instantly processed ham. Mixed application of 89 ppm Na-nitrite and 300 ppm of culture broth concentrate of Monascus isolate No. 116 and 500 ppm of red color produced by Monascus isolate No. 229 showed similar results with the single application of 94 ppm Na-nitrite. These results confirmed that the antimicrobial activity and red pigment of Monascus strains might be valuable to replace Na-nitrite salt in meat processing.

• KSBB Journal
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• v.18 no.6
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• pp.479-484
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• 2003

34 strains were isolated from dyeing wastewater in order to improve treatment efficiency of dyeing wastewater containing PVA. Two strains of them were finally selected through the PVA degrading test, and identified as Microbacterium barkeri LCa and Paenibacillus amylolyticus LCb. As a result, optimal conditions for microbial growth and PVA degradation were 30$^{\circ}C$, neutral pH, starch as a carbon source, and peptone as a nitrogen source. And it was concluded that these two strains have good ability for PVA degradation. And 90% over PVA was degraded by single culture as well as a mixed culture of 2 different strains.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.419-426
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• 2015

The aims of this study were to isolate spore-forming Bacillus strains that exhibit high digestibility and anti-pathogenic bacteria toward feed for calves. Total 136 spore-forming strains were isolated from finished feeds and their ingredients. Among them, 93 strains were identified as Bacillus species when analyzed by 16S rRNA sequencing. For industrial use, three strains named as Bacillus licheniformis SHS14, B. subtilis LCB7, B. amyloliquefaciens LCB10 were selected after evaluating the industrial standards that are related with heat and acid resistance, enzyme activities, and anti-pathogenic activities against Samonella dublin ATCC15480 and E. coli K99. After each culture, 3 selected strains were mixed together at 1:1:1 (v/v/v) ratio and then prepared as the mixed starter culture for feeding. The changes in microbial community were analyzed via 16S rRNA metagenomics. The initial community ratio among three strains was maintained even after manufacturing into final products. Also, in vitro, enzymatic and anti-pathogenic activities were almost same as those when cultured in single culture, and results of anti-pathogenic activities conducted with calves showed 90% activities against lincomycin, which would be indicative of a promising feed starter.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.660-665
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• 2008

The aim of this work was to investigate the microbiological and physicochemical properties of the rice sourdough for Jeungpyun prepared by mixed culture of Saccharomyces cerevisiae (S. cerevisiae) and Leuconostoc mesenteroides (L. mesenteroides) strains. The rice sourdough was fermented with S. cerevisiae and L. mesenteroides strains in rice dough for 24 hours at $30^{\circ}C$. Growth of L. mesenteroides strain was decreased after inoculation, however, it increased again after 18 hours of dough fermentation, and the growth of S. cerevisiae showed a typical growth pattern. Also, total aerobic microorganisms counts in rice sourdough were decreased due to the produced organic acids and ethanol during dough fermentation. These products led to a favorable fermentative quotient (FQ; molar ratio between lactic to acetic acid) value of $1.9{\sim}3.2$ and more stable fermentation for rice sourdough formation. The expansion ratio and viscosity were considerably increased by mixed cultivation of S. cerevisiae and L. mesenteroides strains. Addition of the brown rice at 10% (w/w) to dough preparation increased the relative expansion ratio to the highest value.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.1
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• pp.100-110
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• 2020

Objective: The objective of this study was to isolate proteolytic microorganisms and evaluate their effects on proteolysis in total mixed ration (TMR) silages of soybean curd residue. Methods: TMRs were formulated with soybean curd residue, alfalfa or Leymus chinensis hay, corn meal, soybean meal, a vitamin-mineral supplement, and salt in a ratio of 25.0: 40.0:30.0:4.0:0.5:0.5, respectively, on a basis of dry matter. The microbial proteinases during ensiling were characterized, the dominate strains associated with proteolysis were identified, and their enzymatic characterization were evaluated in alfalfa (A-TMR) and Leymus chinensis (L-TMR) TMR silages containing soybean curd residue. Results: Both A-TMR and L-TMR silages were well preserved, with low pH and high lactic acid concentrations. The aerobic bacteria and yeast counts in both TMR silages decreased to about 10⁵ cfu/g fresh matter (FM) and below the detection limit, respectively. The lactic acid bacteria count increased to 10⁹ cfu/g FM. The total microbial proteinases activities reached their maximums during the early ensiling stage and then reduced in both TMR silages with fermentation prolonged. Metalloproteinase was the main proteinase when the total proteinases activities reached their maximums, and when ensiling terminated, metallo and serine proteinases played equally important parts in proteolysis in both TMR silages. Strains in the genera Curtobacterium and Paenibacillus were identified as the most dominant proteolytic bacteria in A-TMR and L-TMR, respectively, and both their proteinases were mainly with metalloproteinase characteristics. In the latter ensiling phase, Enterococcus faecium strains became the major sources of proteolytic enzymes in both TMR silages. Their proteinases were mainly of metallo and serine proteinases classes in this experiment. Conclusion: Proteolytic aerobic bacteria were substituted by proteolytic lactic acid bacteria during ensiling, and the microbial serine and metallo proteinases in these strains played leading roles in proteolysis in TMR silages.

• Archives of Pharmacal Research
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• v.15 no.1
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• pp.30-34
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• 1992

In order to obtain acetaminophen, a popular analgesic-antipyretic, through microbial p-hydroxylation and N-acetylation of aniline, various fungi and bacteria were secreened. Among them, Streptomyces species were chosen for strain improvement by the use of interspecific protoplast fusion technique. Two interspecific fused strains were developed between S. rimosus (N-cetylation function) and S. aureofaciens (p-hydroxylation function) and also between S. lividans and S. globisporus. For efficient protoplast fusion and cell wall regeneration, various conditions were examined. In a typical experiment of mixed S rimosus ($pro^- \;his^-$) and S. aureofaciens ($ilv^-$) protoplasts with 40% (w/v) polythylene glycol 3350 (PEG) for 3 min gave $8.3\times10^{-7}$ of fusion frequency. Treatment of mixed S. lividans (pant-) and S. globisporus (leu-) protoplasts with 50% (w/v) PEG for 3 min at $30^\circ{C}$ gave $1.2\times10^{-6}$ of frequency. Among the fused strains, up to 40-50% increase in p-hydroxylation power was observed. To investigate the possibility of plasmid involvement in p-hydroxylation power was observed. To investigate the possibility of plasmid involvement in p-hydroxylation of acetanilide, plasmid curing was attempted. We found that cells treated with acriflavine (at the frequency of 100%) and cells regenerated from protoplsts of S. auroefaciens (2% frequency) lost their p-hydroxylation function.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.722-728
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• 2002

Eight strains producing bacterial cellulose (BC) were isolated from rotten fruits and traditionally fermented vinegars. One of the isolated strains from the rotten grape in Gwangju, Korea, maintained a relatively stable BC production in shaking cultures. This isolated strain proved to be Acetobacter xylinum, based on several biochemical and morphological tests. It was shown that the slant-baffled flask was more efficient than the conventional flask for the BC production in shaking cultures. To determine the most suitable carbon and nitrogen sources for the production of BC, various compounds were examined. Fructose was found to be the most effective carbon source with an optimal concentration of 2%. Mixed carbon source (glucose:fructose=1:3) was also better than glucose or fructose alone. Optimal nitrogen source, when basal medium was used, was 10% (v/v) com steep liquor (CSL). When com steep liquor was used with a mixed carbon source (glucose:fructose=1 :3),4% CSL exhibited the best BC production. Based on these results, a defined medium was developed for the BC production by Acetobacter xylinum KJ-1. When this medium was used under optimal culture conditions, the BC production was 7.2 g/1, which was approximately 3 times higher than that with the traditional HS medium.

• Food Science of Animal Resources
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• v.43 no.5
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• pp.877-888
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• 2023

We studied the proteolysis and conducted a sensory evaluation of fermented sausages using strains derived from Kimchi [Pediococcus pentosaceus-SMFM2021-GK1 (GK1); P. pentosaceus-SMFM2021-NK3 (NK3)], Doenjang [Debaryomyces hansenii-SMFM2021-D1 (D1)], and spontaneous fermented sausage [Penicillium nalgiovense-SMFM2021-S6 (S6)]. Fermented sausages were classified as commercial starter culture (CST), mixed with GK1, D1, and S6 (GKDS), and mixed with NK3, D1, and S6 (NKDS). The protein content and pH of GKDS and NKDS were significantly higher than those of CST on days 3 and 31, respectively (p<0.05). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the NKDS had higher molecular weight proteins than the GKDS and CST. The myofibrillar protein solubility of the GKDS and NKDS was significantly higher than that of the CST on day 31 (p<0.05). The GKDS displayed significantly higher pepsin and trypsin digestion than the NKDS on day 31 (p<0.05). The hardness, chewiness, gumminess, and cohesiveness of the GKDS were not significantly different from those of the CST. The GKDS exhibited the highest values for flavor, tenderness, texture, and overall acceptability. According to this study, sausages fermented using lactic acid bacteria (GK1), yeast (D1), and mold (S6) derived from Korean fermented foods displayed high proteolysis and excellent sensory evaluation results.

• KSBB Journal
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• v.6 no.4
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• pp.363-368
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• 1991

PVA degrading bacteria were isolated from water system, and identified as Pseudomonas cepacia and Pseudmonas pseudomallei, which were named as Pseudomonas sp. G5Y and Pseudomonas sp. PW. It was found out that those two kinds of bacteria have a symbiotic relationship to degrade PVA. For the mixed culture of these bacteria, the optimal conditions of pH, temperature, nitrogen source, and polymerization degree of PVA were found to be 7.5, $35^{\circ}C$, ammonium sulfate, and 500, respectively. Also, the growth of these bacteria was promoted by trace elements such as vitamin B1, B12, pyridoxine, and p-aminobenzoate, respectively. The specific growth rate of mixed bacteria was inhibited when the concentration of PVA was more than 20g/l. The substrate inhibition kinetics of the mixed culture was $${\mu}=\frac{0.065S}{2.56+S+(S^2/156}hr^{-1}$