• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.734-738
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• 1999

Bacterial strain showing the ropy characteristics was isolated from Korean wheat bread. Morphology of the isolate was rod and biochemical test revealed that the isolate was Bacillus subtilis. Growth of rope bacteria was about the same as other Bacillus species and inhibited below pH 5.6. Rope bacteria isolated from Korean wheat bread could not survive under the heat treatment of 10 min at $100^{\circ}C$, but could survive at $90^{\circ}C$.

• Journal of Life Science
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• v.8 no.2
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• pp.145-157
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• 1998

We isolated 100 Vobrio sp. from marine products and sea from July to September, 1997. We attemped on purification of hemolysin produced by Vibrio sp. The growth, hemolysin production patterns by the 100 strains of Vibrio sp. showed identical, in general. V. unlnificus ys-1 produced hemolysis as the higtest titer. The optimal culture conditions for the hemolysin production by the V. vunificus ys-1 are followings; 1. Hemolysin production was optimal dering the late exponetial phage. 2. Maximal growth, hemolysin production were in heart infusion broth. 3. Maximal yields of hemolysin was obtained when the heart infusion broth had an intial pH of 8.0, 3$0^{\circ}C$, 3% NaCL. Hemolysin was purified from culture filtrate of the strain by ammonium sulfate recipitation, ion exchange and hydrophobic interaction chromatography. The results were as follows; 1. Hemogeneity of the purified hemolysin was demonstrated by revealing single band on SDS-PAGE. The molecular weight of purified hemolysin was 45KDa. 2. The absorbance rattern in ultraviolet wsa typical of those seen with most proteinb with 280nm. 3. Purified hemolysin was atable at 5$0^{\circ}C$ but 7$0^{\circ}C$ of the acivity was lost by heating for 30 min at 6$0^{\circ}C$/ Optimal temperature of purified hemolysin was 35$^{\circ}C$. 4. Purified hemolysin was stable at the pH range of 6~9, but in the less the pH5.0. above the pH 9.0, the hemolysin activity was lost completely.

• Journal of Plant Biology
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• v.22 no.1_2
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• pp.21-27
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• 1979

Sandy loam plots of pH 5.5, which was created by the reclamation of highlands in Yongin county, Kyeonggi province, was selected for the present experimental study. Sugar beet was cultured in these plots by treating them with calcium hydroxide and 3 replications to maintain pH 5.5, 6.4, 6.8, 7.2, and 7.6, respectively. The growth and yield of sugar beet were investigated and the results obtained showed a great deal of boron deficiency. The growth in its early stage was favorable in high pH plots, while no significant difference was observed in sugar content, root weight and sugar production at the time of harvest in each treated plot. The tendency of sugar accumulation appeared to be identical in terms of pattern in each treated plot; i.e. sugar was accumulated until early September but declined momentarily from the middle of September and then the sugar accumulation was resumed from the middle of October. The number of individuals in boron deficiency was larger in high pH plots and the condition of such boron deficiency was also severe. The result of analysis of boron contained in plant body revealed that the boron content of individuals caused boron deficiency by water culture and that occurred in the plots was small alike. The appearance of boron deficiency is characterized by the emergence of black stripes on the surface of the basal part of petiole, severe necrosis of young leaves in the area of growing point and severe wrinkles. Therefore it is felt necessary to pay particular attention to boron deficiency in the culture of sugar beet in our country.

• Journal of the Korean Ceramic Society
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• v.35 no.8
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• pp.783-790
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• 1998

The characterization of the complexation reaction of PVA and Al(III) ion at different pH and the sint-ering behaviour of UO2 containing the PVA-Al(III) complexes were investigated. Compared with pure PVA powder the complexed PVA-Al(III) powder had compacter shape and lower decomposition temperature The major phase of PVA-Al(III) complex decomposed at 90$0^{\circ}C$ was $\alpha$-Al2O3 The PVA-Al(III) complex formed at pH 9 had the lowest relative viscosity the highest Al content of 36% and the smallest particle size of 19${\mu}{\textrm}{m}$ While the pure UO2 pellet appeared with bimodal one. The grain size of the pure UO2 pellet was 7${\mu}{\textrm}{m}$ but that of the PVA-Al(III) complex added UO2 pellet was increased up to 36${\mu}{\textrm}{m}$ The largest grain size was ob-tained when the PVA-Al(III) complex formed at pH9 was added and the PVA-Al(III) complex formed at pH 11 had the greatest effect on increasing pore size.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.3
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• pp.198-200
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• 2007

Cultivation of a $Q_{10}$-producing photosynthetic bacterium, Rhodobacter sphaeroids, was carried out in a 1-L flask to characterize its cellular growth reaction. The result of experiment showed that dissolve oxygen in the broth was depleted within 7 h. ORP decreased with decrease of DO, and recovered somewhat with increase of pH. The growth of R. spahaeroids reached at late-log phase in 140 h of reaction. The final pH and dry-cell weight were 7.62 and 2.2 mg/mL, respectively. The $Q_{10}$ content in the final broth was 2.35 mg/g dry cell weight, which was higher than that obtained in tube culture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1113-1118
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• 2010

The antioxidative activities and growth inhibitory effects of fermented soymilk (FS) by Bacillus subtilis KC-3 (KCCM 42923) in AGS human gastric adenocarcinoma cells were studied during fermentation at pH 5.5, 5.25 and 5.0. The pH of B. subtilis KC-3 from Cheonggukjang, decreased from 6.8 to 5.0 during the fermentation. The acidity decreased, but amino and ammonia type nitrogen contents increased significantly as pH decreased. FS at pH 5.0 (FS 5.0) exhibited the highest DPPH free radical scavenging activities among other samples. The hydroxy radical scavenging activity of FS 5.0 was found to be approximately 2.5 times higher than that of the non-fermented soymilk (NFS). The SOD-like activity of FS 5.0 was 32.1% at 1.0 mg/mL and 50.6% at 2.0 mg/mL compared to the NFS of 9.1% and 17.3%, respectively. FS, especially FS 5.0, showed increased anticancer effect in AGS human gastric adenocarcinoma cells. These results suggest that soymilk fermented by B. subtilis KC-3 has increased antioxidative activities and anticancer effects during fermentation (pH 6.0 to pH 5.0).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.4
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• pp.166-173
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• 2021

The rutile phase of TiO₂ forms a stable phase at high temperatures compared to anatase phase, but the stable temperature range of anatase changes depending on the synthesis conditions. In this study, nano-sized TiO₂ was synthesized by the Sol-gel method using TiOSO₄ and a mixed solvent of ethanol and distilled water, and the phase change of anatase and rutile according to pH and heat treatment temperature was investigated. Changes in the ratio of anatase and rutile were observed by changing the pH (3, 5, 7, 9) and heat treatment temperature (500, 600, 700, 800, 900℃) conditions of the prepared TiO₂. As a result of observing these changes through XRD and FE-SEM analysis, anatase TiO₂ at 500℃ and rutile TiO₂ at 900℃ were observed. According to the pH, at these intermediate temperatures of 600, 700 and 800℃, the ratio of anatase and rutile changes. At 700℃, it was concluded that pH = 3~5 had a larger ratio of anatase TiO₂, and pH = 7~9 had a larger ratio of rutile TiO₂.

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.874-878
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• 2012

In the submerged fermentation of fungi, it was known pH had significant effect on the citric acid production. Various growth conditions were applied with different buffer on citric acid production by Aspergillus niger NRRL 567 grown on peat moss to find the optimum pH and most effective buffer solution. The initial pHs of different buffer solutions significantly influenced on the citric acid production and A. niger NRRL 567 produced citric acid more efficiently at high pHs. A phosphate buffer and a carbonate buffer with pH 8.6 and pH 10.0 were identified as suitable buffer solutions for citric acid production. The maximal citric acid production of 564.3 g/kg solid substrate was achieved employing carbonate buffer at pH 10.0.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.1
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• pp.131-139
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• 2014

This study was performed to determine the effect of dietary supplementation of procyanidin on growth performance, blood characteristics, and immune function in growing pigs. In experiment 1 (Exp. 1), thirty-two crossbred pigs with an initial BW of $19.2{\pm}0.3$ kg were allocated into 4 treatments for an 8-wk experiment: i) CON (basal diet), ii) MOS 0.1 (basal diet+0.1% mannanoligosaccharide), iii) Pro-1 (basal diet+0.01% procyanidin), and iv) Pro-2 (basal diet+0.02% procyanidin). Pigs fed Pro-1 and Pro-2 diets had greater (p<0.05) gain:feed ratio compared with those fed CON or MOS 0.1 diets. Serum creatinine concentration was less (p<0.05) in Pro-2 treatment than those in CON, MOS 0.1 and Pro-1 treatments. In Exp. 2, twelve pigs (BW $13.4{\pm}1.3$ kg) received basal diet with i) 0 (CON), ii) 0.02% (Pro-0.02%), and iii) 0.04% procyanidin (Pro-0.04%) for 4 wk. Concentration of platelets was lower (p<0.05) in the Pro-0.04% group compared to CON at 24 h after lipopolysaccharide (LPS) challenge. In addition, secretion of cytokines from cultured peripheral blood mononuclear cells (PBMC) in the presence or absence of procyanidin was examined. The levels of interleukin (IL)-$1{\beta}$, IL-6 and tumor necrosis factor (TNF)-${\alpha}$ were lower (p<0.05) in Pro (LPS-stimulated PBMCs+procyanidin) than those in CON (LPS-stimulated PBMCs+PBS) at 4 h after LPS challenge. These data suggest that dietary addition of procyanidin improves feed efficiency and anti-inflammatory cytokines of pigs.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.307-312
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• 2009

The study of candidate genes is an important tool to identify genes associated with economic traits. Three genes were selected to study the association between polymorphism and economic traits and breed of pigs. Growth hormone releasing hormone (GHRH) takes part in growth metabolism and is one of the candidate genes known to be highly associated with economic traits in pigs. Heart fatty acid-binding protein (H-FABP) is related to back fat thickness and intramuscular fat (IMF) content, and myogenin (MYOG) is associated with the amount of growth rate and lean yield in pigs. By PCR-RFLP analysis, the association between the genotypes of the three genes and the average daily gain, back fat thickness, feed conversion, body length and meat percent in 352 pigs (112 Duroc pigs, 132 Landrace pigs and 108 Yorkshire pigs) were analyzed. GHRH polymorphisms showed differences depending on breed (p<0.01) and were associated with meat percent. H-FABP polymorphisms also showed significant differences among breeds and sex (p<0.01), and were highly associated with average daily gain, feed conversion and back fat thickness (p<0.01) and even showed an association with meat percent (p<0.05). However, the MYOG gene showed no significant effect in this study. These results reconfirmed that GHRH and H-FABP are potential major genes or markers for economic traits.