• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.518-525
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• 1988

Lactobacillus casei IFO 3012 and Kluyveromyces fragilis(KFCC 35458) were cultured together in Soymilk to investigate the growth characteristics and the conditions suitable for acid Production. L. casei produced more amount of acid rapidly when cultured with K. fragilis in soymilk than when cultured singly. The optimum conditions for acid production by the mixed cultures of L. casei and K. fragilis were achieved with a temperature of $35-37^{\circ}C$, a 1:5-1:9(O.D 660) ratio of L. casei to K. fragilis at inoculum, a 1.0 level of sucrose fortification or a 2.0% level of skim milk powder fortification and a culture time of 24hr. Under these conditions the amounts of acid produced by the single culture of L. casei and the mixed cultures with K. fragilis were 0.31% and 0.44% in soymilk, 0.43% and 0.97%, respectively, in soymilk fortified with 1.0% level of sucrose. These indicate that the amount of acid produced by mixed cultures is about 1.42 fold greater in soymilk and about 2.26 fold greater in soymilk fortified with 1.0% level of sucrose than that produced by the single culture of L. casei. The amount of acid produced in soymilk fortified with 2.0% level of skim milk powder was 1.0 level for both of the single culture of L. casei and the mixed cultures of L. casei and K. fragilis after 24hr incubation. In soymilk fortified with skim milk power less than 1.5 the mixed culture with K. fragilis showed higher content of acid than the single culture of L. casei only.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1009-1016
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• 2014

This study investigated the probiotic and functional characteristics of Mukeunji starter, Lactobacillus curvatus ML17, isolated from Mukeunji. Lb. curvatus ML17 was confirmed as a safe microorganism due to its non-hemolytic activity and non-production of harmful ${\beta}$-glucuronidase and ${\beta}$-glucosidase. Tolerance to artificial gastric and bile juice of Lb. curvatus ML17 was investigated. After incubation in artificial gastric and bile juice, the number of surviving cells was $1.38{\times}10^8$ CFU/mL. According to the results of adhesion assay, this strain also exhibited good adhesion to Caco-2 cells. Lb. curvatus ML17 showed good antimicrobial activity against food borne pathogens, especially Micrococcus luteus, Bacillus cereus, Salmonella enterica subsp. enterica, and Pseudomonas aeruginosa. Cell-free extract of Lb. curvatus ML17 exhibited high levels of DPPH scavenging capacity and inhibitory effects on growth of AGS human gastric adenocarcinoma cells and HT-29 human colon carcinoma cells. These results suggest that Lb. curvatus ML17 has potential for application in functional foods.

• Korean Journal of Environmental Agriculture
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• v.26 no.2
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• pp.124-130
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• 2007

Excess application of paper mill sludge (PMS) in field can limit phosphorus uptake by crops because aluminum presented in the sludge can fix or adsorb available phosphorus which is necessary for crop growth. To investigate phosphorus (P) adsorption characteristics of PMS, we examined P adsorption maximum $(X_m)$ using Langmuir isotherm and P adsorption energy constant $(K_f)$ using Freundlich isotherm for PMS without alum, PMS with alum, and composted PMS with alum through a laboratory incubation test. The maximum P adsorption capacities were 800 ${\mu}g\;g^{-1}$ in soil, 47 $mg\;g^{-1}$ in PMS without alum and 61 $mg\;g^{-1}$ in PMS with alum. P adsorption capacity with alum treatment for PMS increased by 30%. That of PMS compost was 68 $mg\;g^{-1}$ and showed that composting increases 11% of P adsorption. Freundlich constant $K_f$ was 22 in check soil, while $K_f$ values in PMS without alum and in PMS with alum were 398 and 426, respectively. After composting, $K_f$ value of PMS compost significantly increased as 1,819. In conclusions, p adsorption capacity for PMS were increased by alum treatment or composting and therefore excess or continuous land application of alum-amended or composted PMS can limit P uptake for crops by reducing available P in sell.

• Food Science and Preservation
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• v.24 no.7
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• pp.942-948
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• 2017

To establish manufacturing technology of tofu shake added with red rice prepared with Monascus purpureus KCCM 60570, the quality characteristics of tofu shake added with M. purpureus KCCM 60570 were investigated. Also, we determined the optimal mixing ratios of raw materials including red rice for manufacturing tofu shake. Monacolin K and mold number of red rice were increased rapidly until $8^{th}$ day of incubation and then gradually increased during the 12 day manufacturing period. As the results, it was considered to be most suitable to prepare red rice for 8 days at $25^{\circ}C$, and inoculate 1% (w/w) M. purpureus KCCM 60570. Sensory evaluation of tofu shake added with red rice and tofu shake without red rice was not significantly different at p<0.05. In sensory evaluation, tofu shake added with 0.5% (w/w) red rice was higher in taste, texture, and overall acceptability than the other. Therefore, the optimal mixing ratio of red rice and tofu shake is 0.5% (w/w). These results suggest that the addition of red rice could improve the quality of tofu shake.

• Korean Journal of Agricultural Science
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• v.13 no.2
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• pp.279-288
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• 1986

One hundred and fifty one mutant strains were obtained from the parent strain Aspergillus oryzae MF by ultra-violet ray irradiation. Among those mutants a strain, Asp. oryzae UM-36 which hyperprodued protease, was selected and its morphological characteristics and the production of enzymes protease, ${\alpha}$-amylase, and glucoamylase on wheat bran koji and on soy-sauce koji were studied. The results obtained were as follows 1. The selected mutant showed slower growth and weak sporulation on malt agar and on Czapek agar than the parent strain. 2. The conidiophores of the mutant were generally shorter than those of the parent when grown on malt agar. 3. Sectoring in colonies was not found when grown on malt agar and on Czapek agar. 4. The level of protease production by the mutant was increased approximately 1,4-fold higher on wheat bran koji and 2-fold higher on soysauce koji than by the parent. 5. The production of ${\alpha}$-amylase and glucoamylase by the mutant were also increased as compared with the parent on wheat bran koji and on soy sauce koji. 6. In the case of parent strain and mutant strain, the highest activity of protease appeared after three days in wheat bran medium at $30^{\circ}C$ incubation, but the highest activities of ${\alpha}$-amylase and glucoamylase appeared after two days.

• Journal of Life Science
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• v.25 no.2
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• pp.164-173
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• 2015

To investigate the effect of lactic acid bacteria on the heavy metal adsorption from internal organs and blood, lactic acid bacteria were isolated from human feces. Some strains resistant to heavy metals were selected by incubation in agar media containing each of chrome and cadmium salts. Among them, a strain named KP-3 was ultimately chosen due to its higher growth rate in selective broth medium containing the heavy metals at the concentration of 0.01%. The strain was identified as Lactobacillus sp. based on its morphological, cultural and physiological characteristics. For evaluating the ability to prevent accumulation of heavy metals by selected Lactobacillus sp. strain in vivo, Sprague Dawley rats were fed with heavy metal salts (cadmium, chrome and lead) with or without cultured whole cells for 7 days. The amounts of heavy metals accumulated in liver, kidney and blood were analyzed. As a result, chrome was accumulated to kidney mostly, and lead was frequently found in liver and kidney. Experimental group (rats fed with lactic acid bacteria) showed less accumulation of heavy metal than control group (rats fed with saline solution). The inhibition rates of heavy metal accumulation were calculated to 41.8% (Cd), 33.4% (Cr) and 44.2% (Pb). Especially, feeding lactic acid bacteria strongly reduced accumulation of cadmium in blood. The results showed that feeding Lactobacillus sp. KP-3 could prevent the bioaccumulation of heavy metals in the living body.

• Journal of Pharmaceutical Investigation
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• v.26 no.1
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• pp.33-41
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• 1996

In order to study the effect of phenobarbital(PB) on the hepatic transport of diltiazem(DTZ), $Ca^{2+}$ channel blocker, we used isolated hepatocytes of rat which was intraperitoneally pretreated with phenobarbital sodium(75 mg/kg) for four days once a day. For the isolation of rat liver cells, a modification of the two step procedure of Seglen was used. DTZ was dissolved in incubation buffer to the final DTZ concentrations of 200, 400, 600, 800 and 1000 ng/ml in order to elucidate the uptake characteristics of DTZ by hepatocytes. Reactions were stopped at 10, 20, 30, 45, 60, 90, 120 and 300 sec. The initial velocity was determined by disappearance of diltiazem in the hepatocyte suspension. On the other hand, to determine the effect of PB on the in vitro hepatic intrinsic clearance of DTZ we obtained the metabolism rates of DTZ in the control and the PB-pretreated rat hepatocyte at various time intervals. According to pretreatment with PB, the size of hepatocyte and the amount of protein per $10^6$ cells were significantly (p<0.01) increased from $26.92{\pm}0.1364\;m$ to $35.31{\pm}1.00\;m$ and from $468{\pm}6.5\;{\mu}g/10^6$ cells to $628.8{\pm}12.1{\mu}g/10^6$ cells, respectively. In the case or hepatic uptake of diltiazem, $K_m$ was not different in the normalization by cell numbers and increased from $2.90\;{\mu}M\;to\;13.89\;{\mu}M$ in the normalization by protein amount. $V_max$ was increased regardless of normalization by protein amount and cell numbers, from $1.21\;{\mu}mole/min \;{\cdot}\;mg\;protein\;to\;3.96\;{\mu}mole/min\;{\cdot}\;mg\;protein\;and\;from\;2.38\;{\mu}mole/min\;{\cdot}\;10^6\;cells\;to\;2.83\;{\mu}mole/min\;{\cdot}\;10^6\;cells$, respectively. The in vitro hepatic intrinsic clearance of DTZ was significantly (p<0.01) increased from $0.640{\pm}0.038\;ml/mim\;{\cdot}\;10^6\;cells\;to\;2.385{\pm}0.212\;ml/min\;{\cdot}\;10^6\;cells$ due to PB-pretreatment. These results suggest that the uptake of DTZ by hepatocyte is extremely fast and PB enhances the hepatic intrinsic metabolic clearance of DTZ.

• Microbiology and Biotechnology Letters
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• v.42 no.4
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• pp.402-406
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• 2014

Six kinds of newly recorded yeasts such as Rhodosporidium diobovatum SY4-2, Cryptococcus bestiolae SY7-1, Kazachstania unispora SY14-1, Kazachstania servazzii SY14-3, Pichia holstii SY20-2 and Cryptococcus tephrensis SY26-1 were screened from sixty one yeasts derived from wild flowers found in Seonyudo, Gogunsanyeoldo, Jeollabuk-do, Korea. All of them grew in 50% glucose-containing yeast extract-peptone-dextrose (YPD) broth and Pichia holstii SY20-2 was also halophile, growing in 20% NaCl-containing YPD broth. All of them, except Cryptococcus tephrensis SY26-1, were assimilated to glucose. Cell-free extract from Kazachstania servazzii SY14-3 showed the highest 98.6% of ${\alpha}$-glucosidase inhibitory activity and maximal production of the ${\alpha}$-glucosidase inhibitor was obtained with 24h incubation at $30^{\circ}C$. The antihypertensive angiotensin I-converting enzyme inhibitory activity of the unrecorded yeasts were showed 58.6-80.4% in their supernatants.

• Journal of Microbiology and Biotechnology
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• v.23 no.2
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• pp.225-236
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• 2013

Among several bacteria examined, an antibacterial-producing Lactobacillus strain with probiotic characteristics was selected and identified based on 16S rRNA gene sequencing. Subsequent purification and mode of action of the antibacterial compounds on target cells including E. coli were investigated. Maximum production of the antibacterial compound was recorded at 18 h incubation at $30^{\circ}C$. Interestingly, antibacterial activity remained unchanged after heating at $121^{\circ}C$ for 45 min, 24 h storage in temperature range of $70^{\circ}C$ to room temperature, and 15 min exposure to UV light, and it was stable in the pH of range 2-10. The active compounds were inactivated by proteolytic enzymes, indicating their proteinaceous nature, and, therefore, referred to as bacteriocin-like inhibitory substances. Isolation and partial purification of the effective agent was done by performing ammonium sulfate precipitation and gel filtration chromatography. The molecular mass of the GFC-purified active compound (~3 kDa) was determined by Tris-Tricine SDS-PAGE. To predict the mechanisms of action, transmission electron microscopy (TEM) analysis of ultrathin sections of E. coli before and after antibacterial treatment was carried out. TEM analysis of antibacterial compounds-treated E. coli demonstrated that the completely altered bacteria appear much darker compared with the less altered bacteria, suggesting a change in the cytoplasmic composition. There were also some membrane-bound convoluted structures visible within the completely altered bacteria, which could be attributed to the response of the E. coli to the treatment with the antibacterial compound. According to the in vivo experiments oral administration of L. plantarum HKN01 resulted in recovery of infected BALB/c mice with Salmonella enterica ser. Typhimurium.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.533-538
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• 1997

Lactobacillus bulgaricus and Kluyveromyces lactic were inoculated to Jangyeob and Jinpum soymilks single or together after the addition of different amounts of lactose to increase the formation of lactic acid and sensory evaluation. The decrease of pH and the increase of acid production during the fermentation of soy yogurts were more effective when lactose was added. And the single culture method was more effective in decreasing pH and in increasing acid production than the mixed culture method. Without lactose, the growth of lactic acid bacteria in samples increased by mixed culture method than by single culture method. However, the growth of lactic acid bacteria increased more in the by single cultured samples than in the mixed cultured samples by the addition of lactose. Beany flavor decreased more in soy yogurts compared with Jangyeob and Jinpum soy milks, and Jinpum soy yogurts had less beany flavor than Jangyeob soy yogurts. In sour taste, Jangyeob soy yogurt prepared by mixed culture for 36 hr incubation with 4% lactose showed the poorest score, while soy yogurts containing 2% lactose showed significantly better scores and no significant difference compared with milk yogurt. Soy yogurts containing 2% lactose showed no significant difference in overall acceptability compared with milk yogurt.