• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.216-223
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• 2012

Dextran was produced by $Leuconostoc$ $mesenteroides$ SM with various contents of yeast extract and its rheological properties were modulated, via an addition of hydroxypropyl methylcellulose (HPMC) of different viscosities. The conversion yield reached 90% after adding 3% yeast extract, which remained constant, thereafter. The acidity of the cultures was approximately 1.4 and 0.9% after fermentation for 24 h at 25 and $30^{\circ}C$, respectively. The total dextran content (107.3 g/kg) was the highest in the presence of the 3% yeast extract. Under the same conditions, the consistency, viscous modulus (G"), and elastic modulus (G') of the cultures were $37.6\;Pa{\cdot}s^n$, 38 Pa, and 50 Pa, respectively. The rheological properties of the culture were changed drastically by the fortification with HPMC of higher concentration and viscosity. The addition of 10% HPMC (4,000 cp) resulted in a significant increase in G" to 1,950 Pa. Furthermore, adding HPMC to a viscous culture resulted in a remarkable increase in both hardness and firmness.

• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.214-222
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• 2016

This study was performed to increase the production of ${\gamma}$-aminobutyric acid (GABA) by lactic acid bacteria (Lactobacillus brevis CFM11) and manufacture an optimum medium using the sap from Darae (Actinidia arguta). The concentration of GABA in the fermented sap was determined using GABase enzymatic assay. The isolated L. brevis CFM11 produced $605.67{\mu}g/mL$ GABA after incubation for 24 hours at $37^{\circ}C$ in broth. The sap was fermented by L. brevis CFM11 under optimum conditions of $32^{\circ}C$ for 48 hours with 40% rice bran extract, 1.0% sucrose, 3.0% soytone, 0.2% magnesium sulfate, and 0.2% MSG. The fermented sap produced a concentration of $1366.13{\mu}g/mL$ GABA. These results demonstrate that fermenting Darae sap using L. brevis CFM11 can produce a fermented sap beverage with increased GABA content.

• Food Science and Preservation
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• v.16 no.2
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• pp.266-275
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• 2009

To develop new high-quality Yakchobugak, features of Lactococcus lactis-fermented waxy rice paste after addition of some colored powdered agro-food products were investigated. Total and reducing sugars of waxy rice paste fermented by lactic acid bacteria were higher than those of control raw waxy rice paste. Total acidity gradually increased as powder concentration rose, being 1.02-1.56% and 0.96-1.87% in samples fermented with Cucurbita maxima and Capsicum annuum powders, respectively; these values were 3-4 times those in rice fermented with other powders. Fermented waxy rice paste viscosities were lower than those of non-fermented samples. The viscosities of samples fermented with Curcuma longa and Opuntia ficus powders were in the range $100-160{\times}10^4$ centipoise($mPa{\cdot}s$), and those of pastes fermented with Robus coreanus and Camellia sinensis extracts were under $40{\times}10^4mPa{\cdot}s$. Hunter color lightness(L) values decreased and yellowness(b) values rose after fermentation. Waxy rice paste fermented with Robus coreanus showed uniform particle size distribution, and many pores, by scanning electron micrography.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.583-588
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• 2002

Two microorganisms isolated from soybean curd residue (biji) were identified as Enterococcus faecium (51% homology) and Lactobacillus rhamnosus (99.5% homology) by using gram positive identification (GPI) card and API 50 CHL kit, respectively. Ent. faecium grew well in micronized full-fat soyflour (MFS) milk, indicating pH 4.9, 0.38% acidity and 1.8$\times$10$^{9}$ CFU/$m\ell$ of viable cell counts after fermentation for 20 hr. L. rhamnosus LL showed pH 6.5 and 4.6$\times$10$^{8}$ CFU/$m\ell$ viable cell counts, but enhanced acid production in MFS milk mixture fortified with skim milk or by the addition of 1% of glucose and lactose. On the other hand, Ent. faecium LL did not show increased acid production in MFS/skim milk and MFS milk fortified with sugar. The MFS/skim milk fermented by L. rhmnosus LS and Ent. faecium LL showed 600 mg% and 350 mg% lactic acid, respectively.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.438-445
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• 2015

The production of GABA was optimized by co-cultivation of immobilized Lactobacillus plantarum K154 (ILK) with Ceriporia lacerata cultures. The mycelial culture of C. lacerata was performed in a defined medium containing 3% glucose, 3% soybean flour, and 0.15% $MgSO_4$ in a submerged condition for 7 days at $25^{\circ}C$, resulting in the production of 29.7 g/L mycelia, 3.1 g/L exopolysaccharides, 2% (w/w) ${\beta}$-glucan, 68.96 unit/mL protease, and 10.37 unit/mL ${\alpha}$-amylase. ILK in C. lacerata culture showed viable cell counts of $3.13{\time}10^9CFU/mL$ for immobilized cells and $1.48{\time}10^8CFU/mL$ for free cells after 1 day. GABA production in the free and immobilized cells was 9.96 mg/mL and 6.30 mg/mL, respectively, after 7 days. A recycling test of ILK in the co-fermentation was consequently performed five times at $30^{\circ}C$ for 15 days, resulting in the highest production of GABA. GABA could also be efficiently overproduced by co-cultivation with the produced polysaccharides, ${\beta}$-glucan, peptides, and probiotics.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.308-315
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• 2011

The purpose of this work was to examine the antimicrobial activity derived from the lactic acid bacterium, UK-3 isolated from the vaginas of women of childbearing age. Various physiological and biochemical properties of this strain were characterized. Both the BIOLOG system and phylogenetic analysis using 16S rRNA sequencing were utilized for identification, and the strain was designated as Lactobacillus plantarum UK-3, and registered in GenBank as [JK266589]. Growth rate, production of organic acids (e.g., lactic acid and acetic acid), and pH during growth were monitored. The maximum concentrations of lactic acid and acetic acid were approximately 684.11 mM and 174.26 mM, respectively, and pH changed from 7.0 to 3.7 after 72 h of incubation. High performance liquid chromatography was used to confirm lactic acid and acetic acid production. Significant antimicrobial activity of the concentrated supernatant was demonstrated against various Gram-positive (e.g., Staphylococcus aureus, Staphylococcus epidermidis, Methicillin-resistant Staphylococcus aureus, Enterococcus faecalis, Neisseria species., Listeria monocytogenes), Gram-negative bacteria (e.g., Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis), and yeast (e.g., Candida albicans) by the plate diffusion method. As a result, the concentrated L. plantarum UK-3 cultures had lower acidity and inhibited the growth of all microorganisms tested, whereas the growth of L. acidophilus was not affected.

• Journal of Animal Science and Technology
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• v.50 no.4
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• pp.573-580
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• 2008

This study was aimed to investigate that training of horses is related with the activity of superoxide dismutase(SOD) in erythrocyte of racing horses. The SOD activity was assayed from erythrocyte of six Thoroubred horses having final stage of training, about 21 month-old, 474~509 kg body weight for race trainig. During 7 weeks of training period from 24th Sep. to 6th Nov, horses were bled very carefully 4 times at 1st Oct, 16th Oct, 30th Oct. and 6th Nov. As the training period passed, erythrocyte of the horses have gradually increased the MnSOD activity(p<0.05) and lowered the CuZnSOD activity. The plasma ceruloplasmin and peroxidase activities, and lactate levels were reduced gradually while peroxide and glucose levels gradually increased. The calculated oxygen consumption(Eaton, 1995) for training of horses were linearly related with the MnSOD activity(r=0.650, n=32) but negatively with CuZnSOD activity in erythrocyte and lactate levels(r=－349, n=32) in plasma. Also, peroxide levels in plasma of horses had positive relation with the MnSOD activity in erythrocyte(r=0.616, n=48). In conclusions, as the training is progressed, the raised MnSOD activity in erythrocytes and peroxide levels in plasma indicated balances between oxidant and antioxidants for the protection from ROS during race of horses. The results showed that the MnSOD activity in erythrocyte and peroxide levels in plasma may be used as marker for the intensity of training racing horses.

• Korean Chemical Engineering Research
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• v.56 no.4
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• pp.453-460
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• 2018

Owing to rising oil prices and anthropogenic global warming, focused attempts are being made toward production of industrially important compounds by using renewable biomass. In this context, algal biomass as third-generation biomass is important because it doesn't compatible with food resource, has high yield, and helps abate greenhouse gases. Here, we investigate whether Undaria has the highest sugar content, which would make it the most suitable biomass for lactic acid production among the four algal biomasses tested. For effective pretreatment of Undaria, the response surface methodology was used. The amount of solid loaded and catalyst concentration were related to the extraction rate of total sugar. Lactic acid was produced by pretreatment of Undaria by using four Lactobacilli, and L. alimentarius and L. brevis were found to be suitable for lactic acid production.

• The Korean Journal of Zoology
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• v.32 no.1
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• pp.34-39
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• 1989

Ouabain, strychnine sulfate, caffeine sodium benzoate and chlorpromazine hydrochloride were introduced intraperitoneally into male mice for 7, 14 and 21 days to induce the changes in the relative percentages of lactate dehydrogenase isozymes. The five isozymes in brain, heart and kidney tissues were electrophoresed on cellulose acetate strip and subjected to densitometry. Ouabain caused a drastic increase of B$_4$isozymes only in brain tissues. The two stimulants altered the relative percentages of $A_4$and B$_4$isozymes conspicuously in brain tissues, whereas virtually no redistributions of five isozymes were occurred by the depressant except B$_4$isozymes in brain and heart tissues. On the basis of these observations, it might be suggested that the changes in intracellular concentration of sodium and calcium ions are not the cause of the isozyme redistributions and that Organization of plasma membrane could be one of the factors involved in the tissue specificity of lactate dehydrogenase isozymes in vertebrates.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.476-482
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• 2006

This paper studied the recovery of organic acid from organic acid salt by using bipolar membrane electrodialysis. Acetic acid and lactic acid was used as for organic acid. Organic acid concentration, sodium hydroxide concentration and pH values were measured at various current density. Organic acid salt was effectively converted to organic acid and sodium hydroxide. Based on the experimental results, mathematical models were developed, in which time changes in ion balance were considered. Model predictions of organic acid concentration, sodium hydroxide concentration and pH values were in good agreement with the experimental data.