• Food Science of Animal Resources
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• v.30 no.1
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• pp.66-72
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• 2010

Pediococcus pentosaceus SA131 was isolated from jeotgal, is the bacteriocin producer against bovine mastitis pathogens, Streptococcus uberis E290, Enterococcus gallinarum E362, and Staphylococcus epidermidis ATCC 12228. The medium composition for pediocin SA131 production by P. pentosaceus SA131 was optimized using response surface methodology. Component of medium was studied as carbon source (glucose, fructose, lactose, glycerol, sucrose, maltose, and mannitol), nitrogen source (beef extract, yeast extract, peptone, malt extract, and tryptone), mineral and surfactant ($MgSO_4$, $KH_2PO_4$, $(NH_4)_2SO_4$, $MnSO_4$, NaCl, sodium acetate, and Tween 80). Through one factor-at-a-time experiment, glucose, fructose, yeast extract, malt extract, NaCl, $MgSO_4$, and Tween 80 were determined as the good ingredient. The effects of major factors for pediocin SA131 production were investigated by two-level fractional factorial designs (FFD). By a $2^4$ FFD, fructose, yeast extract, and $MnSO_4$ were found to be the important factors for the bacteriocin production. Subsequently, a $2^3$ central composite design (CCD) was adopted to derive a statistical model for optimizing the composition of the fermentation medium. The estimated optimum composition for the production of pediocin SA131 by P. pentosaceus SA131 was as follows; 0.13% fructose, 1% glucose, 1.8% yeast extract, 2.58% $MnSO_4$, 0.2% NaCl, and 0.2% Tween 80. The pediocin production under optimized medium was increased to 1,000 AU/mL, compared to the 400 AU/mL in MRS medium.

• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.238-242
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• 2009

Pediococci selective medium (PSM) supplemented with ampicillin (A) reported as valid for the detection and enumeration of pediococci included in foods and animal feed was evaluated for the selective detection of the genus Pediococcus in kimchi. PSM is based on the complex basal medium MRS supplemented with cysteine hydrochloride, vancomycin, novobiocin, and nystatin. In the medium evaluation with known species, the growth inhibition of leuconostocs, Pediococcus pentosaceus, Lactobacillus casei, Lactobacillus curvatus, Oenococcus oeni, and Streptococcus thermophilus was not confirmed. In the application of kimchi samples on the selective medium, leuconostocs, P. pentosaceus, Weissella koreensis, Lb. curvatus, Lactobacillus brevis, and Lactobacillus sakei were detected. PSM+A was proved to be not applicable for the detection of pediococci in kimchi.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.763-766
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• 2010

An efficient and simple fermentation process was developed for the production of ${\gamma}$-aminobutyric acid (GABA) by Lactobacillus sakei B2-16. When the L. sakei B2-16 was cultivated in the rice bran extracts medium containing 4% sucrose, 1% yeast extract, and 12% monosodium glutamate, the maximum GABA concentration reached 660.0 mM with 100% conversion yield, showing the 2.4- fold higher GABA concentration compared with the modified MRS medium without the rice bran extracts. The GABA production was scaled-up from a laboratory scale (5 l) to a pilot (300 l) and a plant (5,000 l) scale to investigate the application possibility of GABA production to industrial fields. The production yields at the pilot and plant scales were similar to the laboratory scale using rice bran extracts medium, which could be effective for the low-cost production of GABA.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.288-299
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• 2015

Lactobacillus brevis BK11 obtained from Baikkimchi was selected to study the effects of culture medium, initial pH, atmosphere composition, incubation temperature and time, and prebiotics on growth and production of antimicrobial substances. Growth and antimicrobial substances production of L. brevis BK11 were significantly higher in MRS broth than in BHI or M17 broth. The production of cell mass, lactic acid, and bacteriocin by BK11 strain was at maximum in MRS broth adjusted to pH 6.0. Aerobic and microaerobic conditions were favored cell growth and antimicrobial substances production than anaerobic condition. Biomass and lactic acid production and antimicrobial substances activity of BK 11 were significantly better at 30 and $37^{\circ}C$ than at $25^{\circ}C$. Growth of the strain BK11 entered the stationary growth stage at 24 h after inoculation, and decreased after 36 h. Antimicrobial activities of cell-free culture supernatant and bacteriocin solution were highest when cultured in MRS broth with an initial pH 6.0 for 24-30 h at $37^{\circ}C$. In addition, the highest cell number and lactic acid and bacteriocin production were recorded in the presence of 1 and 2% (w/v) fructooligosaccharide (FOS), however, inulin and raffinose did not affect biological and physicochemical characteristics and antimicrobial activities of L. brevis BK11 cultures. According to these results, production of antimicrobial substances by L. brevis KB11 was closely associated with cell density. Under optimal conditions for antimicrobial substances production, L. brevis BK11 effectively inhibited the growth of Helicobacter pylori ATCC 43504.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.1-6
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• 2006

This study was carried out to evaluate the growth characteristics of Lactobacillus acidophilus KCCM 32820 and Propionibacterium freudenreichii KCCM 31227 in MRS (De Man-Rogosa-Sharpe), RCM (Reinforced Clostridial Medium) and whey broth. Bacterial growth, increase rate of TTA (Total Titratible Acidity) and decline rate of pH in broth were the greatest in 9-21 hr after culturing Lactobacillus acidophilus KCCM 32820 in MRS. Those were the greatest in 24-60 hr after culturing Propionibacterium freudenreichii KCCM 31227 in RCM. However changes of pH and TTA of broth were the greatest in 18-54 hr after culturing Propionibacterium freudenreichii in RCM after culturing Lactobacillus acidophilus in MRS for 36 hr. Viable cells of Lactobacillus acidophilus KCCM 32820 and Propionibacterium freudenreichii KCCM 31227 revealed larger numbers in 12% whey broth than in 6% whey broth. These also showed larger numbers in pasteurized whey broth than in sterilized whey broth. Lactobacillus acidophilus KCCM 32820 and Propionibacterium freudenreichii KCCM 31227 grew best in pasteurized 12% whey broth.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.429-436
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• 2003

Pediocin K1 is a bacteriocin produced by Pediococcus sp. KCA 1303-10, isolated from traditionally fermented flatfish in Korea. Pediocin K1-dependent antibiosis and pediocin K1-independent antibiosis against Listeria monocyrogenes were investigated by comparing antibiosis potential of the ped＋ wild-type strain of Pediococcus sp. KCA1303-10 with that of the ped- mutant strain in 3 different media at 3 different temperatures. In the synthetic MRS-APT medium, bacteriocin (pediocin K1)-dependent antibiosis (BDA) acted as the major driving force of overall antibiosis at the initial stage before the pH of the media was not sufficiently lowered, while bacteriocin-independent antibiosis (BIA) took over the major role at the late stage of antibiosis by killing otherwise resistant cells in the modium. The role of BDA increased as the temperature of the system decreased. The antibiosis potential of BDA among the overall antibiosis of Pediococcus against Listeria at $37^{\circ}C$ was calculated as 46%, and as 75% at $25^{\circ}C$. In the skim milk medium, antibiosis of Pediococcus against Listeria was weakened more than 4 log cycles compared to that of the synthetic medium; however, BDA worked as the main antibiosis force regardless of the culturing temperature in the skim milk medium. In the bean soup medium, BDA also worked as the major killing mechanism against Listeria, but BIA played as another suppressing mechanism against otherwise pediocin-resistant Listeria population. These results suggest that a large portion of the inhibitory action of the ped+Pediococcus sp. KCA1303-10 was attributable to the bacteriocin produced by the strain and that viable Pediococcus sp. KCA1303-10 was superior to the purified bacteriocin in suppressing the occurrence of the bacteriocin-resistant Listeria monocytogenes in food systems.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.169-175
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• 2011

The ${\beta}$-xylosidase (EC 3.2.1.37) production capabilities of lactic acid bacteria in the genus Leuconostoc, isolated from a variety of kimchi (fermented vegetables), were examined. The intracellular levels of ${\beta}$-xylosidase were similar to the extracellular levels, when most Leuconostoc lactic acid bacteria were grown in a medium containing xylose as the carbon source. Intracellular ${\beta}$-xylosidase with a maximum activity of $1.2{\pm}0.1units/mL$ (mean${\pm}$standard error) was obtained from Leuconostoc lactis KCTC 13344, which was isolated from fermented Chinese cabbage. The optimum reaction conditions for Leu. lactis KCTC 13344 ${\beta}$-xylosidase activity were pH 6.0 and $30^{\circ}C$, and the addition of most divalent cations, except zinc, to the reaction mixture resulted in a slight increase in enzyme activity. Compared with a media containing other carbon sources, the ${\beta}$-xylosidase activity was 5 times higher when Leu. lactis KCTC 13344 was grown in a medium containing xylose as carbon source. Zymographic analysis indicated that the synthesis of Leu. lactis KCTC 13344 ${\beta}$-xylosidase (approximate size, 64 kDa) is induced by xylose. A maximum intracellular ${\beta}$-xylosidase activity of $7.1{\pm}0.3units/mL$ was obtained in a batch cultivation in an MRS medium containing 30 g/L xylose.

• Korean Journal of Agricultural Science
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• v.38 no.3
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• pp.473-477
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• 2011

A number of health benefits have been claimed for probiotic bacteria such as Bifidobacterium (B) spp. Lactobacillus(L) acidophilus, and Lactococcus(Lc) cremoris. Viability of probiotic bacteria is important in order to provide health benefits. Only a limited culture media for the test purpose of probiotic bacteria are commercially available (MRS broth), but the media for large-scale propagation of viable cells which are able to be used as food additive are not available. The manufacture of a low priced and preferred novel medium for probiotic bacteria was therefore, attempted using whey protein concentrate(WPC) and Makgeolli sludge as a starting material. The effect of WPC and Makgeolli sludge on the growth of four strains (B. bifidum 15696, B. longum 15707, L. acidophilus CH-2, and Lc. cremoris 20076) was investigated. Medium prepared such as WPC, Makgeolli sludge, and WPC+Makgeolli sludge(WPCMs). It was observed that the growth of 4 strains (B. bifidum 15696, B. longum 15707, L. acidophilus CH-2, and Lc. cremoris 20076) was stimulated by Makgeolli sludge, WPC, WPCMs. Especially, Viable cell number of 4 strains in the WPCMs were higher than that of the single media. These result suggest the possibility that Makgeolli and WPC, acts as a growth factor for the growth of probiotic bacteria.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.3
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• pp.344-348
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• 2006

This study was carried out to survey the effect of medicinal herbs on the growth of 3 strains of lactic starter cultures in MRS broth by the addition of 0, 1, 3, 5, and 10% water extract, after 30 hrs incubation. The pH, titratable acidity and O.D. of lactic acid bacteria were investigated to obtain fundamental knowledge for the development a new product. The effects of medicinal herbs extracts on the growth of lactic acid bacteria were variable depending upon the species of lactic acid bacteria and medicinal herbs extract. Growth of Str. thermohilus was activated by addition of 1 and 3% Angelica gigas water extract, but the basal medium plus 5 and 10% extract and growth of L. acidophilus and Bif. longum were depressed by the addition of extract. The pH and acid production ability dropped slightly in the basal medium plus 1 and 3% of extract. The other samples following the same trend as the control.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.384-389
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• 2009

To isolate lactic acid bacteria having high exopolysaccharides (EPS) production ability, 50 strains were initially isolated from the sourdough. Twenty-one strains formed highly mucoid colonies on the sucrose agar medium, which are indicative of active EPS synthesis. DU-07, DU-10, DU-12, DU-19, and DU-21 produced $11.51{\pm}0.167$, $13.09{\pm}0.193$, $12.72{\pm}0.108$, $11.61{\pm}0.284$, and $13.32{\pm}0.094\;g/L$ EPS, respectively, in MRS medium. The isolated strains, DU-10, DU-12, and DU-21, were identified as Enterococcus flavescens, Enterococcus faecium, and Lactobacillus amylovorus, respectively, by using API 50CHL kit and determining partial sequences of their 16S rDNA. Especially, L. amylovorus DU-21 showed the highest production of EPS, as well as the highest inhibitory activities against pathogenic (p<0.05). Interestingly, the L. amylovorus DU-21 seem to be endemic to sourdough fermentations, as they have not been isolated from other environments.