• Title/Summary/Keyword: growth pH

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A Study on Listeria Strain Species for Fishes and Shellfishes on Sale (시판되는 어 .패류에 대한 Listeria 속균의 조사연구)

  • 김동필;조배식
    • The Korean Journal of Food And Nutrition
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    • v.14 no.6
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    • pp.548-561
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    • 2001
  • Listeria spp. from sea water, fishes and shellfishes have been troubled in many countries. So we exam ined its distribution rates, biochemical characteristics of a separated strain, growth curve of pH at set times to 4 species of standard strain, and yes or no of growth inhibition for precautionary measure of food poisoning by L. monocytogenes, garlic, mustard, wasabi, and green tea extracts including sensitivity of antibiotics 10 species. As its results, check numbers of its positivity to Listeria spp. were 32 species in total examination body 200 species, and its isolation rates were 16%, L. innocua was 14.0%, L. monocytogenes 1.0%, and L. seeligeri 1.0% by the strain species. All the standard strain of 4 species showed growth inhibition bellow pH 3.0, its pH conditions of the optimum growth at 7.0∼8.0, and its growth was more active in alkali co]tuition than in acid condition. Its growth inhibition examination by garlic extracts had an the worst effects with O.D values of 0.078∼0.210. But the case of mustard and wasabi had weakened effect, and the case of green tea had some effect as the time went by. The results of sensitivity examination of antibiotics 10 species were as fellows. L. innocua of the 16 cases showed sensitivity of 100% in all 5 species, Ampicillin, etc, and Ciprofloxacin showed sensitivity of 43.7% and gentamicin, 93.7%. But tetracycline showed tolerance of 31.3% , cefotaxine. 75%, nalidixic acid, 100%. L. monocytogenes of the 6 cases showed sensitivity of 100% in all 6 species, ciprofloxacin, etc.

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Effect of Sulfur Application on Mulberry Growth and Chemical Composition of Soil and Leaf. (황시용이 뽕나무의 생육 및 토양과 뽕잎의 화학성에 미치는 영향)

  • 이원주;임수호
    • Journal of Sericultural and Entomological Science
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    • v.37 no.2
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    • pp.109-113
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    • 1995
  • Effects of sulfur application on mulberry growth and soil chemical properties were examined in mulberry trees grown in a green house. Mulberry graftages were planted in Wagner pots and sulfur was applied at the levels of 0, 30, 60, or 120 kg/10a. Mulberry stem growth increased by 3.2 cm at 30 kg/ha than at 0 kg/ha sulfur application. Stem growth, however, decreased by 3.7 cm with the application of sulfur higher than at 60 kg/10a. Soil pH changed by the application of sulfur. With the application of sulfur at 120 kg/10a, soil pH decreased by 3.0. Temporal changes in the effective from sulfur content in soil indicated that sulfur dissolved between 4 to 10 days after application in the soil. Content of moisture and chemical components in mulberry leaves was also affected by the application levels of sulfur. Moisture, total-N, No3-N, K, and S content decreased, but F and Ca content increased with the application of sulfur lower than at 60 kg/10a. With the application of sulfur higher than at 60 kg/10a, P, S, and K content increased.

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Effect of Rhodophyta extracts on in vitro ruminal fermentation characteristics, methanogenesis and microbial populations

  • Lee, Shin Ja;Shin, Nyeon Hak;Jeong, Jin Suk;Kim, Eun Tae;Lee, Su Kyoung;Lee, Sung Sill
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.1
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    • pp.54-62
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    • 2018
  • Objective: Due to the threat of global warming, the livestock industry is increasingly interested in exploring how feed additives may reduce anthropogenic greenhouse gas emissions, especially from ruminants. This study investigated the effect of Rhodophyta supplemented bovine diets on in vitro rumen fermentation and rumen microbial diversity. Methods: Cannulated Holstein cows were used as rumen fluid donors. Rumen fluid:buffer (1:2; 15 mL) solution was incubated for up to 72 h in six treatments: a control (timothy hay only), along with substrates containing 5% extracts from five Rhodophyta species (Grateloupia lanceolata [Okamura] Kawaguchi, Hypnea japonica Tanaka, Pterocladia capillacea [Gmelin] Bornet, Chondria crassicaulis Harvey, or Gelidium amansii [Lam.] Lamouroux). Results: Compared with control, Rhodophyta extracts increased cumulative gas production after 24 and 72 h (p = 0.0297 and p = 0.0047). The extracts reduced methane emission at 12 and 24 h (p<0.05). In particular, real-time polymerase chain reaction analysis indicated that at 24 h, ciliate-associated methanogens, Ruminococcus albus and Ruminococcus flavefaciens decreased at 24 h (p = 0.0002, p<0.0001, and p<0.0001), while Fibrobacter succinogenes (F. succinogenes) increased (p = 0.0004). Additionally, Rhodophyta extracts improved acetate concentration at 12 and 24 h (p = 0.0766 and p = 0.0132), as well as acetate/propionate (A/P) ratio at 6 and 12 h (p = 0.0106 and p = 0.0278). Conclusion: Rhodophyta extracts are a viable additive that can improve ruminant growth performance (higher total gas production, lower A/P ratio) and methane abatement (less ciliateassociated methanogens, Ruminococcus albus and Ruminococcus flavefaciens and more F. succinogenes.

The culture conditions for mycelial growth and sclerotial formation of Polyporus umbellatus

  • Lee, Min Woong;Chang, Kwang Chun;Shin, Do Bin;Lee, Kyung Rim;Im, Kyung Hoan;Jin, Ga-Heon;Shin, Pyung Gyun;Xing, Yong Mei;Chen, Juan;Guo, Shun Xing;Lee, Tae Soo
    • Journal of Mushroom
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    • v.11 no.4
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    • pp.194-200
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    • 2013
  • Polyporus umbellatus (Syn. Grifola umbellata) is a sclerotium forming mushroom belongs to family Polyporaceae of Polyphorales, Basidiomycota. The sclerotia of P. umbellatus have long been used for traditional medicines in China, Korea and Japan. This study was initiated to obtain the basic data for artificial sclerotial production of P. umbellatus. Here, we investigated the favorable conditions for mycelial growth of P. umbellatus and its symbiotic fungus Armillaria mellea. We also evaluate the favorable carbon and nitrogen sources for sclerotial formation in dual culture between P. umbellatus and A. mellea. The favorable conditions for mycelial growth of P. umbellatus were $20^{\circ}C$ and pH 4, while optimal conditions for mycelial growth of A. mellea were $25^{\circ}C$ and pH 6. The carbon sources for optimal mycelial growth of P. umbellatus were fructose and glucose, while carbon sources for favorable mycelial growth of A. mellea were also fructose and glucose. The nitrogen sources for favorable mycelial growth P. umbellatus were peptone and yeast extract, while optimal mycelial growth of A. mellea were obtained in peptone and yeast extract. When P. umbellatus and A. mellea were dual cultured on carbon sources, sclerotia were induced on basal media supplemented with glucose, fructose and maltose at pH 4~6, while nitrogen sources inducing sclerotia were basal media supplemented with peptone and yeast extract for 60 days at $20^{\circ}C$ under dark condition.

Studies on Artificial Cultivation of Poria cocos (복령(茯岺)의 인공배양(人工培養)에 관한 연구(硏究))

  • Park, Jong-Jin;Ham, Hyung-Bae;Lee, Min-Wung
    • The Korean Journal of Mycology
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    • v.8 no.3
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    • pp.133-142
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    • 1980
  • Poria cocos, a parasite on Pinus densiflora was studied for its optimum growing condition from May 1, 1979 to November 15, 1980. 1) The optimum pH value was 5.0, and it had poor growth below pH 3.0 and no growth above pH 7.0. 2) The optimum temperatures were $25{\sim}27^{\circ}C$, and it had poor growth below $5^{\circ}C$. 3) On Robbins and Herrey's solid media, malt extract(diameter of colony at 2% of the above material was 90mm) and tomato extract(at 8% was 90mm) gave the best growth. 4) By Badcock method, the best growth was obtained in P.D.A. supplemented with accelerator 5% of the above material of liquid media(85mm in diameter of colony) and malt extract 2% of P.D.A. added with accelerator 5% of them of liquid media(410mg of hyphae of dry weight) but the growth rate was poor in the media of wood extract agar supplemented with accelerator 5% of the above material giving 30mm diameter of the colony. 5) The growth on Robbins basal medium supplemented with Quercus accutissima extract showed 305. 3mg of hyphae of dry weight and Robinia pseudoacasia was supplemented with it showed 256.3mg of them. 6) The best growth was obtained in Jennison basal medium supplemented with L-asparagine showing 44.3mg of hyphae of dry weight.

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Two-Stage Fermentation for 2-Ketogluconic Acid Production by Klebsiella pneumoniae

  • Sun, Yuehong;Wei, Dong;Shi, Jiping;Mojovic, Ljiljana;Han, Zengsheng;Hao, Jian
    • Journal of Microbiology and Biotechnology
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    • v.24 no.6
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    • pp.781-787
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    • 2014
  • 2-Ketogluconic acid production by Klebsiella pneumoniae is a pH-dependent process, strictly proceeding under acidic conditions. Unfortunately, cell growth is inhibited by acidic conditions, resulting in low productivity of 2-ketogluconic acid. To overcome this deficiency, a two-stage fermentation strategy was exploited in the current study. During the first stage, the culture was maintained at neutral pH, favoring cell growth. During the second stage, the culture pH was switched to acidic conditions favoring 2-ketogluconic acid accumulation. Culture parameters, including switching time, dissolved oxygen levels, pH, and temperature were optimized for the fed-batch fermentation. Characteristics of glucose dehydrogenase and gluconate dehydrogenase were revealed in vitro, and the optimal pHs of the two enzymes coincided with the optimum culture pH. Under optimum conditions, a total of 186 g/l 2-ketogluconic acid was produced at 26 h, and the conversion ratio was 0.98 mol/mol. This fermentation strategy has successfully overcome the mismatch between optimum parameters required for cell growth and 2-ketogluconic acid accumulation, and this result has the highest productivity and conversion ratio of 2-ketogluconic and produced by microorganism.

Effects of Liming and Nitrogen Sources on the Yield and Quality of Burley Tobacco. I. On the Growth Characteristics, Yield and Quality. (석회와 질소원이 버어리종 담배의 수량과 품질에 미치는 영향 I. 생육, 수량 및 품질에 미치는 영향)

  • 김상범;한철수;김대송
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.32 no.3
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    • pp.310-316
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    • 1987
  • A field experiment was conducted to find out the effects of liming(soil pH) and sources of N on growing characters and yield of burley tobacco. Treatments consisted of liming(nonliming, liming to soil pH5.5 and 6.5) as the main plot and N sources(compound fertilizer of containing 3.9% NH$_4$-N and 6.1% NH$_2$-N, NaNO$_3$,(NH$_2$)$_2$CO and (NH$_4$)$_2$SO$_4$as the sub-plot. The growth of vegetative growing stage of limed plots were delayed(to compare the nonlimed plot) by influence of alkali. When the source on N was NaNO$_3$ the growth of vegetative growing stage was unfavorable and the yellowing of lower leaves of maturing stage was rapid. The yield and value of cured leaf was increased by increasing the rate of Ca(OH)$_2$, but there was no significant differences among the source of N. The yield response to liming was greater when the source of N was (NH$_4$)$_2$SO$_4$ than that of any other plots.

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Isolation and Growth Characteristics of Alkalophilic Bacillus sp. for Removal of Anthraquinone Dye. (Anthraquinone계 염료의 제거를 위한 호알칼리성 Bacillus sp.의 분리와 성장 특성)

  • 김정목
    • Microbiology and Biotechnology Letters
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    • v.29 no.2
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    • pp.67-71
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    • 2001
  • Isolation and Growth Characteristics of AIkalophilic Bacillus sp. for Removal of Anthraquinone Dye. Kim, Jeong-Mog. School of Environmental Information, Taekyeung College, Kyungsan, 712-850, Korea -Alkalophilic strain degrading and decolorizing anthraquinone dye, Remazol brilliant blue R was isolated from natural system and named as Bacillus sp. ARB!. The optimal temperature and pH of Bacillus sp. ARBI were 35°C and 9.0, respectively. The pH of culture media during the fermentation were changed from 10 and 10.5 of initial values to 9.3 and 9.4 after 40 hrs, respectively. Decolorization efficiency in aerobic shaking culture of Bacillus sp. ARBI was markedly higher than that in standing culture. At the optimal culture condition, decolorization efficiency by the Bacillus sp. ARBl was 93% after 32 hrs batch culture. In the case of batch culture using real dye processing wastewater, dye decolorization efficiency of Bacillus sp. ARBl was 78% after 40 hrs.

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Culture characteristics of Leuconostoc mesenteroides WiKim32 in kimchi cabbage juice without supplements and sterilization (비살균 무첨가 배추즙에서 Leuconostoc mesenteroides WiKim32의 배양 특성)

  • Han, Eung Soo
    • Korean Journal of Food Science and Technology
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    • v.51 no.4
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    • pp.343-347
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    • 2019
  • This study was performed to develop an economical culture method of lactic acid bacteria (LAB) for kimchi fermentation. Leuconostoc mesenteroides WiKim32 was grown to $1{\times}10^9CFU/mL$ and maintained at 8.88 log CFU/mL for four days by culturing in kimchi cabbage juice (KCJ) without supplements and sterilization. Leuconostoc mesenteroides WiKim32 was cultured in 100 mL of KCJ by inoculating with 0.1% starter culture and adding 100 mL of KCJ everyday by adjusting pH to 5.5 using 1 M NaOH at $20^{\circ}C$ for four days. KCJ was prepared by extraction of kimchi cabbage leaves after washing them with citric acid and ethanol. Adjusting pH over 6.0 was favorable for the growth of LAB in the initial stage, but LAB growth was retarded in the later stage. In contrast, adjusting pH below 5.0 was not beneficial for the growth of LAB; therefore, pH was adjusted to 5.5.

Effect of plant growth regulators and carbon sources on proliferation and shoot formation of PLBs in Dendrobium candidum (철피석곡의 기내 Protocorm Like Bodys(PLBs) 재증식 및 신초형성에 미치는 생장조절제 및 탄소원의 영향)

  • Jang, Jee-woo;Kim, Chang Kil;Trinh, Ngoc Ai;Lee, Do-Jin;Chung, Mi Young
    • Journal of Plant Biotechnology
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    • v.46 no.1
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    • pp.9-16
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    • 2019
  • Dendrobium candidum Wallich ex Lindley is a traditional Chinese medicine plant and has been widely used for medicinal and ornamental purposes. In this study, several different factors affecting micro propagation of protocorm-like bodies (PLBs) such as basal media, plant growth regulators, and carbon sources. The proliferation PLB derived from seeds was the best in $H_3P_4$ basal medium containing $0.1mg{\cdot}L^{-1}$ NAA and $0.1mg{\cdot}L^{-1}$ Kinetin. PLB growth was the best when $10g{\cdot}L^{-1}$ sucrose was added to the carbon atoms in the medium. The rate of shoot formation from the propagated PLB was the highest in 1/4 MS or $H_1P_2$ medium containing $10g{\cdot}L^{-1}$ sucrose, and the shoot length was longer than the others.