• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.111-118
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• 1988

The growth inhibition of enteropathogenic Escheriohia coli $A_2$and Escherichia coli G$_7$, causing the diarrhea in piglets, by the organic acid producing bacteria was studied in vitro. The metabolites of the organic acid bacteria, such as lactic acid, acetic acid inhibited the growth of E. coli $A_2$and E. coli G$_7$ in BL medium. The more the organic acid producing bacteria have ability to produce the organic acids, the higher these bacteria excelled the inhibitory efficacy against enteropathogenic E. coli. Among the strains examined, Lactobacillus casei Y and Streptococcus faecium C showed relatively strong growth inhibition against enteropathogenic E. coli.. When the organic acid producing bacteria and the enteropathogenic E. coli were incubated simultaneously in BL medium, bacteriostasis of E. coli was observed when the pH of BL culture was lowered to 5.0, and bacteriocidal effect was observed when the pH became Bess than 4.5, E. coli. $A_2$was more resistant to the organic acid bacteria than E. coli G$_7$.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.4
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• pp.973-981
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• 2007

In the present study, we investigated the antiproliferative activity of the water extract of Samgibopae-tang (SGBPT) in NCI-H460 and A549 non-small-cell lung cancer cell lines. We found that exposure of A549 cells to SGBPT resulted in the growth inhibition in a dose-dependent manner as measured by MTT assay, however SGBPT did not affect the growth of NCI-H460 cells. The antiproliferative effect by SGBPT treatment in A549 cells was associated with morphological changes such as membrane shrinking and cell rounding up. SGBPT treatment did not induce the cell cycle arrest in both cell lines, however the frequency of sub-G1 population was concentration-dependently increased by SGBPT treatment in A549 cells. SGBPT treatment partially induced the expression of tumor suppressor p53 in A549 cells and the expression of cyclin-dependent kinase inhibitor p21(WAF1/CIP1) was markedly increased in both transcriptional and translational levels in A549 cells. The up-regulation of p21 by SGBPT occurred in a similar a concentration dependent manner to that observed with the inhibition of cell viability and induction of sub-G1 population of the cell cycle. However SGBPT treatment did not affect other growth regulation-related genes such as early growth response-1 (Egr-1), nonsteroidal anti-inflammatory drug-activated gene-1 (NAG-1), inducible nitric oxide synthease (iNOS), cyclooxygenases (COXs), telomere-regulatory factors in A549 as well as NCI-H460 cells. Taken together, these findings suggested that SGBPT-induced inhibition of human lung carcinoma A549 cell growth was aoosciated with the induction of p21 and the results provided important new insights into the possible molecular mechanisms of the anti-cancer activity of SGBPT.

• Journal of Environmental Science International
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• v.24 no.10
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• pp.1309-1313
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• 2015

The effects of Houttuynia cordata powder on the growth performance of ducks were investigated. Ninety ducks were assigned into one of three dietary treatments as a completely randomized design for 6 weeks: feeds supplemented with 1% or 2% H. cordata and a control group. No significant difference was observed in feed conversion among the three groups (p > 0.05), but addition of H. cordata had a significantly positive effect (p < 0.05) on initial and final body weight, weight gain, and feed intake of the ducks. Furthermore, the effects of chemical treatment (comprising 50 g and 100 g aluminum chloride [$AlCl_3$] per kilogram litter) on the ammonia ($NH_3$) flux in duck litters were also investigated. Duck litter was treated with $AlCl_3$ at a depth of 8 cm by top-dressing; this resulted in a significant difference on $NH_3$ flux (p < 0.05) during the experimental period (but not at 2 weeks). $NH_3$ flux at 6 weeks were reduced by 25.4% and 37.5% by treatment with 1% and 2% H. cordata, respectively, compared with the control groups. In conclusion, enriching the diets of the ducks with 2% H. cordata and adding 100 g $AlCl_3$ to their litter has beneficial effects on increasing their growth performance and reducing $NH_3$ flux in their environment.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.5
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• pp.607-613
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• 2010

The influence of dietary supplementation with blended essential oil on growth performance, nutrient digestibility, blood profiles and fecal characteristics was evaluated in 125 crossed ((Duroc ${\times}$Yorkshire) ${\times}$Landrace) pigs (6.21${\pm}$0.20 kg initial body weight and 21 d average age). The pigs were allotted to the following treatments: i) NC (antibiotic free diet), ii) PC (NC diet+44 ppm tylosin), iii) T1 (NC diet+0.1% essential oil), iv) T2 (NC diet+0.1% essential oil (with 0.3% Benzoic acid)) and v) T3 (NC+22 ppm tylosin and 0.05% essential oil). Average daily gain (ADG) was improved in the T2 group on d 14 (p<0.05). In addition, nutrient digestibility was partially affected (both positively and negatively) by the treatments. Furthermore, the immune system was stimulated and the fecal pH and fecal noxious gases were improved in pigs that received the diets supplemented with essential oil (p<0.05). The appearance and score of diarrhea also tended to be lower in pigs that were subjected to the essential oil treatments. Collectively, the results of this study indicate that supplementation of the diet with blended essential oils could replace treatment with antibiotics to improve growth performance and fecal characteristics.

• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.131-137
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• 2021

This study aimed at isolating lactic acid bacteria with anti-MRSA (methicillin-resistant Staphylococcus aureus) bacteriocin activity from fermented shrimp. We selected three strains, named Weissella sp. S1, S2, and S3, using analysis based on 16S rRNA gene sequences. All strains showed appropriate growth in an MRS medium containing 5% (w/v) NaCl and showed antibacterial activities against Bacillus cereus, Escherichia coli, Staphylococcus aureus, and MRSA. The strains exhibited similar growth rates at 0-5% NaCl, with approximate reduction in growth rate observed at 9% NaCl. Weissella sp. S1, S2, and S3 exhibited maximum growth rates at pH 7, 9, and 8, respectively. The crude bacteriocin was prepared from Weissella sp. S3 and subjected to characterization. The remaining activities after 30 min of exposure at each temperature were 100%, beyond 75%, and 49% at 4℃ and 37℃, 50℃ and 70℃, and 100℃, respectively. The remaining activities after 24 h of exposure at each pH were 100%, 75%, and 49% at pH 3 and 5, 7 and 9, and 10, respectively. Use of 50% (v/v) ethanol or isopropanol treatment did not diminish the antibacterial activity of the bacteriocin, while the 50% (v/v) hexane treatment reduced the activity by 51%. The molecular weight of the bacteriocin was nearly 6 kDa that was quantified using tricine-SDS-PAGE. Our findings suggest that Weissella sp. S3 may be considered a probiotic and useful source of antimicrobial substances in the development of bio-preservatives for food or in MRSA treatment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.2
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• pp.153-159
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• 2017

We examined changes in the physiological responses of gray mullet Mugil cephalus exposed to acidic seawater (pH 6.0, 6.5, 7.0) and normal seawater (pH 8.0, control) for 15 days. As pH decreased, survival rate and body weight also decreased. Levels of aminotransferase, total protein and triglycerides also differed significantly with changes in pH, presumably due to stress caused by exposure to acidic water. The level of osmotic pressure was significantly higher in the pH 6.0 group than in other groups. Superoxide dismutase was significantly higher in the pH 6.5 and 7.0 groups than in the pH 8.0 group, and glutathione level was lowest in the pH 6.0 group. We conclude that decreasing the pH level of seawater induces a stress response in fish, damaging their ability to control their hematological and osmotic pressure. Antioxidant enzymes are generally sensitive to osmotic stress; in this study, antioxidant activity significantly changed with pH level. These results indicate that physiological stress induced by exposure to acidification reduces survival rates and inhibits growth in M. cephalus.

• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.95-100
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• 2001

In countries that consumes rice as a main staple, rice hulls are natural resources composed of a large amount of organic compounds and high uniformity in size. Rice hulls are expanded to get rid of a defect in untreated rice hulls and to be used as a hydroponic substrate. Research on rice hulls is continuing for the agricultural application. This research was conducted to stabilize rhizosphere pH of the expanded rice hull substrates because of high pH caused by repeated use in ERH(expanded ride hull) substrates and without increasing the cost of developing new substrates. Sphagnum peatmoss (pH 3.0-4.0) wee mixed with the expanded rice hull substrate in the ratio of 10% (v/v), and this ratio kept the pH range of 6.0 to 6.5 in the root area of tomato plants during growth and at the time of harvest of tomato fruits. Also absorbtion of nutrients was highly increased. The yield increased from 1,051 to 1,266 kg per tomato plant which were harvested by two clusters.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1436-1438
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• 1997

In this paper, CdS thin films, which were widely used window layer of the CdS/CdTe and the CdS/$CuInSe_2$ heterojunction solar cell, were grown by chemical bath deposition, and The properties were investigated in detail. Cadmium acetate and thiourea were used as cadmium and sulfur source, respectively. And Ammonium acetate was used as the buffer solution. Also Ammonia was used for controlling pH concentration. The reaction velocity was increased with increasing reaction temperature and decreasing pH concentration. The crystal structure of CdS films grown with various pH concentration had the hexagonal structure with (002) plane peak. In the range of pH $9{\sim}9.5$, the intensity of the peak was highest, and as increasing pH concentration, decreased the intensity of the peak except pH12.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.1
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• pp.48-53
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• 2001

An in vitro study was conducted to examine the effect of sources and the addition levels of carbohydrates on fermentation characteristics, bacterial growth, and hydrogenation of linoleic acid ($C_{18:2}$) by mixed ruminal bacteria. Starch and cellobiose were added to the 200 ml non-selective basal media at the levels of 0.20 and 0.35% (w/v), respectively. Linoleic acid (66.8~79.6 mg) in the absorbed form into the pieces of nylon cloth was also added to the media of 5 treatments including control which was not added with carbohydrate. Three mls of rumen fluid strained through 12 layers of cheese cloth were added to each medium, and were incubated anaerobically in the shaking incubator of $39^{\circ}C$ for 24 hours. During 24 h incubation the pH in incubation media of all treatments was maintained above 6.6 by the addition of sodium bicarbonate. The pH and ammonia concentration of incubation media were not clearly influenced by the sources and addition levels of carbohydrates while additions of carbohydrates increased (p<0.0001) VFA concentration at the 24 h incubation. Molar proportions of acetate were reduced (p<0.0004) while those of propionate were increased (p<0.0006) by the addition of carbohydrates. But the differences in concentration and molar proportions of the VFA were small between the sources or the addition levels. Bacterial growth was faster (p<0.0004) in the starch added treatments than in the cellobiose added ones and control, but no differences were found between addition levels. Increased (p<0.0487) hydrogenation was observed from the starch added treatments compared to the cellobiose added ones, but there was no difference between addition levels.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.67-76
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• 2022

This study aimed to determine the photosynthesis and growth characteristics of Peucedanum japonicum T. grown under aquaponics in a plant factory (AP) by comparing those grown under hydroponic cultivation system (HP). The AP system raised 30 fishes at a density of 10.6 kg·m^-3 in a 367.5 L tank, and at HP, nutrient solution was controlled with EC 1.3 dS·m^-1 and pH 6.5. The pH level ranged from 4.0 to 7.1 for the AP system and 4.0 to 7.4 for the HP system. The pH level in the AP began to decrease with an increase in nitrate nitrogen (NO₃-N) and lasted bellower than pH 5.5 for 15-67 DAT. It was found that ammonium nitrogen (NH₄-N) continued to increase even under low pH conditions. EC was maintained at 1.3 to 1.5 dS·m^-1 in both systems. The concentration of major mineral elements in the fish tank was higher than that of the hydroponics, except for K and Mg. There was no significant difference in the photosynthesis characteristics, but the PIABS parameters were 30.4% lower in the AP compared to the HP at the 34DAT and 12.0% lower at the 74DAT. There was no significant difference in the growth characteristics, but the petiole length was 56% longer in the leaf grown under the AP system. While there was no significant difference in the fresh and dry weights of leaf and root, the leaf area ratio was 36.43% higher in the AP system. All the integrated results suggest that aquaponics is a highly-sustainable farming to safely produce food by recycling agricultural by-products, and to produce Peucedanum japonicum as much as hydroponics under a proper fish density and pH level.