• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.58-58
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• 2002

This study was excuted to decide the physiological characteristics of Pleurotus Ferulae Lanzi. P. Ferulae Lanzi. was tested to select pertinent substract, temperature and pH range for the growth. Mycelial growth of P. Ferulae Lanzi. was mostly supported on MYPA among other tested synthetic or semi-synthetic media. The temperature range for pertinent mycelial growth was about 25~32$^{\circ}C$ and mostly stimulated at $25^{\circ}C$. And the pertinent pH range of MYPA was 5.0~6.0. The required carbon and nitrogen source for mycelial growth of P. Ferulae Lanzi. was tested. The mycelial growth was mostly stimulated by soluble starch at content. The carbon sources for pertinent mycelial growth was starch or maltose. And the nitrogen source for pertinent mycelial growth was yeast extract.

• Journal of Bio-Environment Control
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• v.12 no.2
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• pp.89-94
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• 2003

This study was conducted to identify the effect of recycling method of drained solution on the concentration of drained solution, and growth and yield of tomato in the recycling system. The recycling methods of drained solution were composed of control, MEC (measurement of EC) and ANS (analysis of nutrient solution). The plant height in the early growth stage was not different among the treatments, but plant fresh weight and dry weight were higher in the MEC or the ANS than in the control. The growth including fruit number, fruit weight, and yield of tomato in the ANS as compared with the control was favorable. The EC of drained solution tended to decrease in the early growth stage, but that of drained solution increased in the late growth stage. It was low in the MEC and the ANS as compared with the control. The pH of drained solution was maintained by 6.2 to 6.5 throughout the growth period in the MEC and the ANS, but the pH of the control increased up to 7.2 at the late growth stage. The N and K concentrations of drained solution tended to decrease in the early growth stage, while those of P, Ca and Mg increased. In the late growth stage, concentrations of N, P, Ca and Mg tended to decrease, but that of K in the ANS was very low. Concentrations of N, P, K, Ca and Mg were lower in the MEC and the ANS than in the control.

• Korean Journal of Poultry Science
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• v.27 no.3
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• pp.227-233
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• 2000

Preset study was carried out to evaluate characteristics of lactic acid producing bacteria(LAB) in hen's cecum as probiotics value. Distribution of LAB in intestinal tracts was investigated using 5∼25 weeks - old hens. So, 12 strains to LAB with different morphology were isolated purely. Acid tolerance of LAB tested at pH 1, 2, 3, and 4, and bile resistant also tested at 0, 0.3% and 0.5% bile salt concentration. Growth pattern of LAB observed to 60h. All strains of cecal LAB couldn't survive at pH 1, and decreased linearly survival colony after incubation at pH 2 although some strains could survive for 2h. Most of LAB maintained constant number at pH 3 and 4. The bacterial action could increase linearly at 0% bile salt concentration in all of tested strains. However, only one strain could multiply at 0.3% bile salt, others were influenced by bile salt. That tendency was similar at 0.5% bile salt. Growth was peaked at 12 to 18 h after innoculation. After peak, the decreasing pattern of colony was different to strains which some strains decreased rapidly or maintained for long time. The LAB of hen's cecum was similar to intolerance acidity, but different to resistant to bile salt and growth pattern by strain. So, we choose three strains which have probiocs value, and identified as Lactobacillus amylovorus LLA7, Lactobacillus crispatus LLA9 and Lactobacillus vaginalis LLA11.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.5
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• pp.451-461
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• 2005

The effect of carbon dioxide on yeast growth was investigated during the cultivation of pH 5.0 and pH 6.8. by replacing the nitrogen part with carbon dioxide under aerobic conditions. The values of the specific growth rate under pH 5.0 and pH 6.8 conditions became 64.0% and 46.9%, respectively, compared to those before the change in gas composition. This suggests that the effect of carton dioxide was greater pronounced in pH 6.8 than in pH 5.0. The genome-wide transcriptional response to elevated carbon dioxide was examined using a DNA microarray. As for upregulated genes, it was noteworthy that 3 genes were induced upon entry into a stationary phase and 6 genes were involved in stress response. Of 53 downregulated genes, 22 genes were involved in the ribosomal biogenesis and assembly and 5 genes were involved in the lipid metabolism. These facts suggest that carbon dioxide could bring the cell conditions partially to a stationary phase. The ALD6 gene encoding for cytosolic acetaldehyde dehydrogenase was downregulated, which would lead to a lack of cell components for the growth. The downregulation of ALD6 was greater in pH 6.8 than in pH 5.0. consistent with physiological response. This suggests that it might be the most effective factor for growth inhibition.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.3
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• pp.280-285
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• 1983

The effect of pH and calcium on the growth of subterraneum clover (Trifolium subteraneum L.) varieties Dwalganup, Mt. Barker, and Tallarook was determined in solution culture. At pH 4.5 and below all components of growth except germination percentage were adversely affected. The effect of lower pH was improved at high calcium level(3.0mM). There was a varietal difference in response to low pH. Mt. Barker showed the highest percent germination and produced the longest radicle length, whereas the greatest value in top dry weight, root dry weight, root length and number of laterals was obtained with Tallarook.

• KSBB Journal
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• v.11 no.6
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• pp.649-653
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• 1996

Imnmobilization characteristics of Thiobacillus sp. IW which oxidizes sulfur compound was studied to use the bacterium in odor controlling equipment for the future. The optimum growth conditions for Thiobacillus sp. IW were pH7, $30^{\circ}C$ and the generation time was 38min, which was extremely fast compared with other sulfur oxidizing bacteria. Optimum growth conditions in activated carbon as a carrier was pH5, $35^{\circ}C$ and those in bioceramics was pH 7∼8, $35^{\circ}C$. Cell growth immobilized in bioceramics was more stable in pH, temperature change than that immobilized in activated carbon and total number of cells in bioceramics were also higher. Based on these results, the bioceramics is thought to be better carrier in immobilization of Thiobacillus sp. IW.

• Korean Journal of Microbiology
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• v.41 no.2
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• pp.152-156
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• 2005

In the present study, lactic acid bacterium that has antibacterial activity against Helicobacter pylori was isolated from feces of newborn baby. The selection was based on the ability to inhibit the growth of H. pylori and to withstand harsh environmental conditions such as acidic pH and high bile concentration. By biochemical test and 16S rDNA sequencing, selected strain was turned out to be an Pediococcus acidilactici, therefore designated to P. acidilactici GMB7330. In order to investigate the inhibitory effects of P. acidilactici GMB7330 on the growth of H. pylori, we have tested in vitro studies such as cell viability and urease test. These results showed that antibacterial activity of P. acidilactici GMB7330 significantly decreased the viable cell count and urease activity of H. pylori. Antibacterial activity of P. acidilactici GMB7330 against H. pylori remained after pH adjustment to neutral, and the concentration of lactate produced from P. acidilactici GMB7330 was not enough to inhibit H. pylori. On the basis of the analysis by transmission electron microscope, it demonstrated that addition of P. acidilactici GMB7330 destroyed the cell structure of H. pylori. These results strongly suggested that P. acidilactici GMB7330 produce antibacterial substances to be able to inhibit the growth of H. pylori other than lactic acid.

• The Korean Journal of Mycology
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• v.9 no.1
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• pp.19-24
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• 1981

The mycelial growth of Agaricus bitorquis and Pleurotus ostreatus in synthetic media were carried out by ordinary methods. The optimum pH and temperature for mycelial growth were from pH 6.0 to 6.5 and 25 to $30^{\circ}C$, and from pH 5.0 to 6.5 and $25^{\circ}C$ in A. bitorquis and P. ostreatus, respectively. Among the carbon and nitrogen sources, glucose, starch, and peptone showed the good result for the mycelial growth of A. bitorquis, and glucose, fructose, starch and peptone were good for the mycelial growth of P. ostreatus. The yield of mycelium decreased under lower or higher C/N ratio. Also, at the same C/N ratio, the higher the concentration of glucose and peptone, the more the yield was increased. Among various vitamins thiamine, Ca-pantothenate and folic acid were suitable for the mycelial growth of A. bitorquis, and thiamine, folic acid and ino­sitol for the mycelial growth of P. ostreatus. Although pH, total nitrogen and glucose contents of media decreased gradually during culture period the yield of mycelium increased.

• The Korean Journal of Ecology
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• v.21 no.1
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• pp.65-72
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• 1998

Various effects of simulated acid rain by $HNO_3$ and $H_2SO_4$ with pH 3.2, 4.2 and 5.6 were investigated in Melilotus suaveolens Ledeb, a biennial legume dominating the disturbed and poor soil vegetations. The nitric acid treatment of pH 3.2 resulted in 121% increase of the plant height compared to that of pH 5.6 during early growth, although 17% decrease was detected with the sulfuric acids. During 14 days of treatment, leaf biomass and chlorophyll content increased 168% and 133% with pH 3.2 nitric acid rain but decreased 20% and 38%, respectively, with sulfuric acid rain. Nitrogen content in various organs was also determined after 42 days of nitric acid treatment. It increased 480% and 387% by pH 3.2 and 4.2 in leaves, 212% and 214% in stems and 247% and 249% in roots. However, the same treatment with the sulfuric acid showed a considerable reduction in this content, indicating that the nitric acid was a nitrogen source. Nodule formation assayed revealed 15% decrease with pH 3.2 in contrast to 157% increase in pH 4.2, further suggesting an enhancement effect by the additional nitrogen source. Contrary to this, the nodule formation was reduced up to 43-71% by sulfuric acid rains. Specific nitrogen fixation activities of nodules estimated at pH 3.2, 4.2 and 5.6 nitric acid rain were 36.7, 42.8 and 47.3 ${\mu}mol\;C_2H_4{\cdot}g^{-1}\;fw\;nodule{\cdot}h^{-1}$, while those of sulfuric acid rain exhibited 1 nmol $C_2H_4{\cdot}plant^{-1}{\cdot}h^{-1}$ with pH 3.2, 177 with pH 4.2 and 179 with pH 5.6, yet it increased 2, 115 and 286 respectively corresponding to the three sulfuric acid concentrations. Further implications of the simulated acied rain were also discussed in the study.

• Mycobiology
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• v.36 no.2
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• pp.88-92
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• 2008

Vegetative growth of four different strains of Hericium erinaceus was observed. The temperature suitable for optimal mycelial growth was determined to be $25^{\circ}C$, with growth observed in the extend temperature range of $20{\sim}30^{\circ}C$. The different strains of this mushroom showed distinct pH requirements for their optimum vegetative growth, with the most favorable growth observed at pH 6. Considering vegetative mycelial growth, PDA, YM, Hennerberg, Hamada, and Glucose peptone were the most favorable media, and Czapek Dox, Hoppkins, Glucose tryptone, and Lilly were the most unfavorable media for these mushroom strains. With the exception of lactose, most of the carbon sources assayed demonstrated favorable vegetative growth of H. erinaceus. For mycelial growth, the most suitable nitrogen source was alanine and the most unsuitable was histidine. Oak sawdust medium supplemented with $10{\sim}20%$ rice bran was the best for mycelial growth of the mushroom.