• Food Science of Animal Resources
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• v.30 no.6
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• pp.946-950
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• 2010

This study evaluated the antimicrobial effects of meat processing-related organic acids on Burkholderia thailandensis (Burkholderia pseudomallei surrogate) with different water activities. B. thailandensis KACC12027 (4 log CFU/mL) was inoculated in microwell plates containing tryptic soy broth pH-adjusted to 4, 5, 6, and 7 with ascorbic acid, citric acid, and lactic acid and with water activities adjusted to 0.94, 0.96, 0.98, and 1.0 with NaCl, followed by incubation at $35^{\circ}C$ for 30 h. The optical density (OD) of the samples was measured at 0, 3, 6, 12, 24, and 30 h at 595 nm to estimate the growth of B. thailandensis. Growth of B. thailandensis was observed only at water activity of 1.0. In general, more bacterial growth (p<0.05) was observed at pH 6 than at pH 7, and the antimicrobial effects of the organic acids on B. thailandensis were in the following order: Ascorbic acid > lactic acid > citric acid after incubation at $35^{\circ}C$ for 30 h. These results indicate that organic acids in meat processing-related formulations should be useful in decreasing the risk related to an emerging high risk agent (B. pseudomallei).

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.115-124
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• 1999

This study was conducted to determine the optimum root zone environment condition and proper nutrient management system for lettuce in hydroponics. For the root zone environment condition, several level of pH and electrical conductivity (EC) were treated respectively. Though all the level of pH 4 to pH 8, except pH 3, performed better growth without any visible physiological disorder, the optimum pH of the nutrient solution for lettuce production was pH 5.5 to 6.0. The optimum ionic strength of the solution was EC 1.2 to 1.6 mS $cm^{-1}$ / because higher nutrient level caused tip burn symptom by calcium deficiency. Considering the above results, it is concluded that lettuce can be efficiently mass-produced through the optimum root zone environment.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.1
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• pp.179-186
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• 1998

We have been investigated the effects of the initial pH of the aquous solution, reaction temperature and time for the flaking of the soda-lime glass container. Flaking of glass occuurred in the cases of the $121^{\circ}C$, above pH 11 of solution with no $Mg^{2+}$ ions in solution. The pH of the solution approached to pH 10 under the conditions of below pH 9 of start solution. The flaking mechanism of the glass seem to be composed of formation of leached layer of $Ca^{2+}$ and $Na^{2+}$ ion and separation of these layers during the cooling by the difference of thermal expansion between leached layer and glass surface. The leaching of alkali ions in glass depends on the pH condition of the start solution and the temperature. In the case of $Mg^{2+}$ ions are added, $Mg^{2+}$ ions accelerate the flaking of the sodalime glasses and forms the magnesium silicate compound which result in the decrease of the pH of the solution.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.144-149
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• 2006

This is a study on relationship between soil pH and flower color and growth of Hibiscus siriacus L, looking for the pH range to result the most ideal flower color. I anticipate this study result will lay a foundation of improved breeding plan of Hibiscus siriacus L. According to the result of investigation and analysis on bleeding peculiarities by each soil pH, the numbers of leaves in Honghwarang and Younggwang reached the highest at pH 7: 188.73 and 135.87 respectively. Increased pH resulted the increased number of leaves. According to the result of investigation and analysis on color changes of four kinds of Hibiscus siriacus L. at various pH level, Honghwarang's L value gradually decreased from 17.05 to 12.26 at pH increase while a value increased from 16.37 to 20.91.

• The Korean Journal of Mycology
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• v.48 no.2
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• pp.75-85
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• 2020

The collection of biological data of indigenous species must comply with the Nagoya Protocol. Fungi contain various bioactive substances making them an attractive source of several products, including food and medicines. In this study, we investigated the growth characteristics of five indigenous fungal strains, Fomitiporia punctata, Polyporus ulleungus, P. brumalis, Gymnopus subnudus, and Tyromyces kmetii, isolated from samples collected in the Ulleungdo Island. The growth rates for each strain were assessed across various temperatures (20 ℃ to 35 ℃), culture media (Potato dextrose agar, Malt extract & Yeast extract agar, Malt extract agar, Malt extract & peptone agar, Sabouraud dextrose agar, and Modified Melin-Norkrans agar), and pH conditions (4.0 to 8.0). Additionally, we assessed the mycelial growth characteristics in liquid culture. The mycelial growth in different media varied across species; specifically, F. punctata (in MMNA), G subnudus (in MMNA), and P. brumalis (in MEPA) showed rapid growth. Optimal growth temperatures ranged between 25 ℃ and 30 ℃ for most species, with the exception of T. kmetii and P. brumalis, which were able to grow across all the temperatures tested. P. brumalis showed the best growth rate, whereas P. ulleungus showed the lowest growth potential. The optimal pH conditions for mycelial growth ranged between 4.0 and 5.0. In experiments using culture flasks, the dry weight of the culture filtrates decreased with the increasing incubation time and showed a significant decrease between 1 and 6 months of incubation, indicating that the five strains take longer than a month to fully use the culture media. Our findings highlight and establish the optimal growth conditions for five different fungal species that can be used in future application studies.

• Asian Journal of Turfgrass Science
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• v.12 no.3
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• pp.237-248
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• 1998

The soil pH favored by Korean wild plants is 5.33~7.20, while naturalized invader species prefer soils of pH 3.95~6.48. The germination rate of Zoysia japonica was inhibited sharply, up to 60%, in extracts of naturalized plants of concentrations over 50%. Erigeron canadensis extract most strongly inhibited germination, while the Korean wild species, Cassia mimosoides var. nomame increased germination rates in concentrations of 30% and 50%. The seedling growth of Zoysia japonica in extracts of Korean wild species and naturalized species did not show differences, but was inhibited strongly, up to 60%, in the extract of Cassia mimosoides var. nomame concentration of over 15%. Analysis of the extract from Cassia mimosoides var. nomame identified procatechuic acid, $\rho$-hydroquinone, $\rho$-coumaric acid and ferulic acid at 254nm; and vanillic acid, hydroquinone, benzoic acid and cinnamic acid were discovered at 284nm. The seed germination and seedling growth of Zoysia japonica were investigated under different concentrations of phenolic compounds. Ferulic acid and vanillic acid were associated with an increased germination rate, while $\rho$-coumaric acid appeared to inhibit seedling growth.

• Journal of Environmental Science International
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• v.24 no.8
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• pp.1075-1084
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• 2015

This study was conducted to investigated the changes in the nutrient components ($NO_3{^-}-N$, $NH_4{^+}-N$, $PO_4{^{3-}}P$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$) and environmental parameters (electrical conductivity, total dissolved solids and pH) on the leaf lettuce (Lactuca sativa L.) grown with hydroponics. Recirculating hydroponic cultivation system was consisted of planting port, LED lamp, water tank, and circulating pump for hydroponic. Nutrient solution was used in the standard solution for Japan vegetables experimental station and commercial hydroponic. The result showed that electrical conductivity (EC), total dissolved solids (TDS) and pH, depending on the growth of lettuce decreased continuously. With the growth of the lettuce, nitrate nitrogen, ammonia nitrogen, phosphate phosphorus were required for periodic replacement. The number of pH compensation due to the growth of lettuce are the most high. The concentration of $Ca^{2+}$ and $Mg^{2+}$ during the lettuce growth showed no significant change. However, $K^+$ concentration increased due to the replacement with nitrogen and phosphorus. Electric conductivity and total dissolved solids with total nutrient concentration showed the linear relationship and the correlation coefficient $R^2$ were 0.8601 and the 0.827, respectively.

• Journal of Animal Science and Technology
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• v.57 no.9
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• pp.31.1-31.11
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• 2015

Background: This study was conducted to investigate the potential association of variation in the insulin-like growth factor binding protein 2 (IGFBP2) gene with growth, carcass and meat quality traits in pigs. IGFBP2 is a member of the insulin-like growth factor binding protein family that is involved in regulating growth, and it maps to a region of pig chromosome 15 containing significant quantitative trait loci that affect economically important trait phenotypes. Results: An IGFBP2 polymorphism was identified in the Michigan State University (MSU) Duroc ${\times}$ Pietrain $F_2$ resource population (n = 408), and pigs were genotyped by MspI PCR-RFLP. Subsequently, a Duroc pig population from the National Swine Registry, USA, (n = 326) was genotyped using an Illumina Golden Gate assay. The IGFBP2 genotypic frequencies among the MSU resource population pigs were 3.43, 47.06 and 49.51 % for the AA, AB and BB genotypes, respectively. The genotypic frequencies for the Duroc pigs were 9.82, 47.85, and 42.33 % for the AA, AB and BB genotypes, respectively. Genotype effects (P < 0.05) were found in the MSU resource population for backfat thickness at $10^{th}$ rib and last rib as determined by ultrasound at 10, 13, 16 and 19 weeks of age, ADG from 10 to 22 weeks of age, and age to reach 105 kg. A genotype effect (P < 0.05) was also found for off test Longissimus muscle area in the Duroc population. Significant effects of IGFBP2 genotype (P < 0.05) were found for drip loss, 24 h postmortem pH, pH decline from 45 min to 24 h postmortem, subjective color score, CIE $L^*$ and $b^*$, Warner-Bratzler shear force, and sensory panel scores for juiciness, tenderness, connective tissue and overall tenderness in MSU resource population pigs. Genotype effects (P < 0.05) were found for 45-min pH, CIE $L^*$ and color score in the Duroc population. Conclusions: Results of this study revealed associations of the IGFBP2 genotypes with growth, carcass and meat quality traits in pigs. The results indicate IGFBP2 as a potential candidate gene for growth rate, backfat thickness, loin muscle area and some pork quality traits.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.7
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• pp.1038-1042
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• 2009

Fifty-four cross-bred ((Landrace${\times}$Yorkshire)${\times}$Duroc) pigs (13.47${\pm}$0.03 kg average initial BW) were evaluated in a 42 d growth assay to determine the effects of the fermented soy product (FSP). The dietary treatments were: FSP 0 (corn-soybean basal diet), FSP 2.5 (FSP 0 amended with 2.5% FSP), and FSP 5 (FSP 0 amended with 5% FSP). The body weight at the end of the experiment increased linearly (p = 0.05) as the FSP levels in the diets increased. In addition, the ADG and G/F ratio also increased (linear effect, p = 0.06) as the levels of FSP increased. However, there was no effect of FSP on ADFI or DM digestibility (p>0.05). Furthermore, the N digestibility increased as the FSP levels increased (linear effect, p = 0.003), although the total protein concentration in the blood was not affected by FSP (p>0.05). Additionally, the albumin concentration was higher in pigs fed diets that contained 2.5% FSP than in pigs in the control group or the FSP 5 group (quadratic effect, p = 0.07). The creatinine concentrations were also evaluated at d 42 and found to be greater in pigs that received the FSP 2.5 diet (quadratic effect, p = 0.09). Moreover, the creatinine concentration increased linearly in response to FSP treatment (p = 0.09). Finally, although the BUN concentration on the final day of the experiment was greater in pigs that received the FSP 2.5 diet (quadratic effect, p = 0.10), there were no incremental differences in BUN concentrations among groups (p>0.05). Taken together, the results of this study indicate that feeding FSP to pigs during the late nursery phase improves growth performance and N digestibility.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.1
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• pp.34-38
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• 2005

Effects of pH level and slurry particle size on material removal rate and planarization of langasite single crystal wafer have been examined. Higher material removal rate was obtained with lower pH level slurries while the planarization was found to be determined by average particle size of colloidal silica slurries. Slurries containing 0.045 ㎛ amorphous silica particles showed the best polishing effect without any scratches on the surface. Effective particle number has a strong effect on the surface planarization and the removal rate, so that the lower effective particle numbers produced low removal rate but the better planarization results.