• 제목/요약/키워드: 산 생성

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Aspergillus kawachii S-27에 의한 Rice-Koji의 제조에 관한연구

  • 소명환
    • Proceedings of the Korean Society for Applied Microbiology Conference
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    • 1979.10a
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    • pp.243.2-243
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    • 1979
  • 현재 우리나라의 탁약주 용 Rice-Koji 제조 용종국균으로 널리 분양되고 있는 분양되고 있는 fawachi, S-27 균주가 생성하는 Amylase의 효소학적 특성과 Rice-Koji i제조 시 유기산 및 당화 효소의 생성 조건을 검토했다. 1. 본 균은 유기산 생성력이 강하고 또 생성하는 당화효소 및 액화효소는 내산성이 극히 강하며 pH3~5의 범위내에서 최고 활성을 나타내었으므로 탁약주 제조 용 종국균으로 아주 적합하였다. 2. 본 균의 발아 최적온도는 36$^{\circ}C$이었으며 Rice -Koji제조시 제국시간을 40시간으로 볼 때 유기산 생성의 최적온도는 32$^{\circ}C$이었고 당화효소 생성의 최적온도는 36$^{\circ}C$이었으며 고온인 4$0^{\circ}C$에서는 유기산 생성이 극히 불량하였다. 3. Rice-Kojiw제조시 당화효소의 생성은 배지의 수분함량 35%일 때 최고치를 보였으며 유기산 생성은 이 보다 높은 조건인 수분함량 40%일 때 이었고 비교적 건조한 조건인 수분함량 30%일 때는 유기산 생성이 특히 불량하였다. 4. 배지의 두께가 3cm이상이 되면 유기산 및 당화효소 생성에 않은 지장을 주었다. 5. 종국균의 점종량은 유기산 및 당화효소의 생성에 별로 영향을 미치지 못했다.

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Effects of Milk Products on Acid Production by Lactic Acid Bacteria in Soy Milk and Quality of Soy Yogurt (두유(豆乳)에 첨가된 유제품이 젖산균의 산생성(酸生成)과 대두요구르트의 품질에 미치는 영향)

  • Ko, Young-Tae
    • Korean Journal of Food Science and Technology
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    • v.22 no.2
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    • pp.183-191
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    • 1990
  • Soy milk prepared from soy protein concentrate was added with each of four types of milk products. Acid production and growth of five species of lactic acid bacteria(LAB) in soy milk and sensory property of soy yogurt were investigated. Acid production by LAB increased in proportion to concentration of milk products added to soy milk. Among the four milk products tested, whey powder or skim milk powder stimulated acid production by LAB more than whole milk powder or modified milk powder. Stimulating effect by whey powder on acid production by LAB was greater than other milk products at low concentration. Acid production by LAB in soy milk added with glucose or milk products significantly increased during fermentation. Sensory property of soy yogurt added with whole milk powder or skim milk powder was better than that of reference (soy yogurt added with glucose) while sensory property of soy yogurt added with whey powder or modified milk powder was Inferior to that of reference.

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Effects of Chitosan on the Production of Th1 and Th2 Cytokines in Mice (키토산이 Th1과 Th2 사이토카인 생성에 미치는 효과)

  • Kim, Kwang-Hyuk
    • Journal of Life Science
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    • v.19 no.3
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    • pp.411-416
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    • 2009
  • Chitosan is derived from chitin by a process of controlled deacetylation. In the present study, we investigated the effects of chitosan on the production of cytokines such as interleukin-2 (IL-2), interferon-$\gamma$ (IFN-$\gamma$), interleukin-4 (IL-4), and interleukin-10 (IL-10) in mice. The culture supernatants of splenocytes exposed with chitosan alone or chitosan plus cell stimulants, lipopolysaccharide (LPS), concanavalin A (Con A), and phytohemagglutinin-P (PHA-P) were harvested to assay IL-2, IFN-$\gamma$, IL-4, and IL-10 production. IL-2, IFN-$\gamma$, and IL-4 from splenocytes exposed to chitosan showed a greater increase compared to the PBS control group. IL-2 and IFN-$\gamma$ levels in the culture supernatants from splenocytes exposed to LPS+chitosan were higher than those of the groups exposed to LPS alone. IL-4 and IL-10 levels in the culture supernatants from splenocytes exposed to LPS+chitosan were lower than those of the groups exposed to LPS only. These findings demonstrate that chitosan upregulates the immune responses by Th1 cytokines (IL-2 and IFN-$\gamma$) and downregulates those by Th2 cytokines (IL-4 and IL-10) in LPS-associated immunity. These results show the potential of its usefulness for balancing the Th1/Th2 immune response, if more research results were accumulated.

Study on Growth and Acid Production by Lactic Acid Bacteria in Soy Milk (두유(豆乳)에서 젖산균의 생육(生育)과 산생성(酸生成)에 관한 연구)

  • Kim, Kyung-Hee;Ko, Young-Tae
    • Korean Journal of Food Science and Technology
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    • v.19 no.2
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    • pp.151-156
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    • 1987
  • Four types of soy milk prepared from soybean, defatted soybean, soy protein concentrate (SPC) or soy protein isolate (SPI) were fermented with Lactobacillus acidophilus, L. bulgaricus, L. casei, Leuconostoc mesenteroides or Streptocroccus lactis. Growth and acid production by each organism in soy milks were investigated. Acid production by L. acidophilus was miximum in soy milk while acid production by other organisms was maximum in defatted soy milk. All the organisms produced least amount of acid in SPI-milk. Addition of yeast extract (0.5) to four types of soy milks stimulated acid production by lactic acid bacteria, particularly in case of L. acidophilus. Higher concentration of total solids in soy milks resulted in better growth and more acid production by L. acidophilus and L. bulgaricus.

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Occurrence of acid producing bacteria in Meju leaves (재래식 메주중의 산생성균의 분포)

  • Hur, Sung-Ho;Ha, Duk-Mo
    • Applied Biological Chemistry
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    • v.34 no.2
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    • pp.130-133
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    • 1991
  • The distribution of acid producing bacteria and general bacteria in 23 samples of Korean traditional Meju loaves was investigated and the strains isolated from the samples identified. The acid producing bacteria occurred more in outer part than inner part and anaerobic acid producing bacteria showed higher tendency of occurrence compared with the aerobes in each part. The average number of nonhalophilic and halotolerant bacteria belonging to aerobes were counted as $24{\times}10^6$ and $33{\times}10^5$ and the average number of those belonging to anaerobes $10{\times}10^7$ and $58{\times}10^5$ cells/g, respectively. The general bacteria isolated more in outer part than inner part and its average number was $62{\times}10^7$ cells/g. In the isolates, 2 aerobic acid producing strains were identified as Micrococcus spp., 3 anaerobic acid producing strains as Streptococcus sp., Pediococcus sp. and Lactobacillus sp., and 2 strains of aerobic general bacteria as Bacillus spp.

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실리콘계 고분자 복합막을 통한 유기산 수용액의 분리

  • 남상용;심진기;최철호;이영무
    • Proceedings of the Membrane Society of Korea Conference
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    • 1998.04a
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    • pp.95-96
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    • 1998
  • 1. 서론 : 발효조를 통해서 생성되는 유기산은 주로 아세트산과 프로피온산으로 나타나는데 이는 배양액중에 2-3% 정도로 희석되어 있다. 이러한 유기산을 선택적으로 분리하여 농축시켜야만 제설제로 사용되는 유기산 염을 제조하는 공정에 적용할 수 있다. 일반적으로 유기산은 석유화합물로부터 얻어지는 것을 사용하여 왔는데 발효조를 통하여 얻어지는 유기산을 이용하는 경우 자원의 재활용을 통하여 얻어지는 생성물을 이용한다는 측면외에도 에너지를 절약할 수 있는 장점을 가질 수 있어서 에너지환경적인 측면에서 기대되는 공정이다. (생략)

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우유와 쌀을 이용한 요구르트의 제조에 관한 연구

  • 홍외숙;고영태
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.10a
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    • pp.216.3-217
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    • 2003
  • 본 연구에서는 우유에 탈지분유 또는 4종의 쌀을 각각 2%(w/v)첨가하여 커드상의 요구르트를 만들고, 대조군(우유로만 만든 요구르트)과 비교하여 쌀의 첨가가 젖산균의 산생성 및 커드상 요구르트의 품질(관능성, 저장성에 미치는 영향을 조사하였으며, HPLC를 이용하여 몇 가지 유기산을 분석하였다. 쌀의 첨가로 젖산균의 산생성이 대조군보다 촉진되었는데 현미의 촉진효과가 가장 현저하였다. 접종된 4종의 젖산균(Lacttobacillus 3종, Leuconostoc 1종) 중에서는 Lenc. mesenteroides 와 L. bulgaricus 의 산생성도가 높았다. HPLC에 의한 유기산 분석의 결과를 보면 우유나 2% 현미를 첨가한 우유에 L. bulgaricus를 접종하여 24시간 발효하는 동안 lactic acid 는 젖산균에 의해 생성되어 그 양이 현저하게 증가하였으나, 우유 중에 들어있는 citric acid 는 젖산균에 의해 이용되어 그 양이 현저히 감소하였다. 커드상 요구르트의 관능성은 쌀의 첨가로 표준시료보다 다소 저하되었으며, 쌀 첨가시료 중에서는 통일벼 참가시료가 다른 시료보다 우수하였다. 커드상의 요구르트를 2주일 간 5$^{\circ}C$냉장고에 저장하는 동안 산생성과 pH, 생균수에 거의 변화가 없어 저장성은 매우 우수한 것으로 나타났다.

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Effects of Methionine Supplemented to Soy Milk on Growth and Acid Production by Lactic Acid Bacteria (두유(豆乳)에 첨가된 Methionine이 유산균의 생육과 산생성에 미치는 영향)

  • Ko, Young-Tae
    • Applied Biological Chemistry
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    • v.30 no.1
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    • pp.17-23
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    • 1987
  • Soy milk prepared from soy protein concentrate was fermented with each of the following lactic acid bacteria: Lactobacillus acidophilus KFCC 12731, L. acidophilus AKU 1122, L. bulgaricus, L. casei, Leuconostoc mesenteroides and Streptococcus lactis. The effects of methionine supple mented to soy milk on the growth and acid production by each organism. were investigated. L-methionine reduced the acid production by two strains of L. acidophilus while it had no apparent. effects on the other test cultures. The inhibitory effects of L-methionine on L. acidophilus KFCC 12731 was greater than on L. acidophilus AKU 1122. The acid production by L. acidophilus KFCC 12731 was also reduced substantially by DL-methionine supplemented to soy milk while it was not affected by D-methionine. Supplementation of L-cysteine to soy milk resulted in slight reduction of acid production by L. acido philus KFCC 12731.

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Effects of Denitrification on Acid Production in a Two-phase Anaerobic Digestion Process (2상 혐기성 소화공정에서 탈질반응이 산생성에 미치는 영향)

  • Park, Sang-Min;Park, Noh-Back;Seo, Tae-Kyeong;Jun, Hang-Bae
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.6
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    • pp.628-636
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    • 2008
  • Anaerobic denitrification in a two phase anaerobic digestion(TPAD) process combined with biological nutrients removal (BNR) system was studied for a piggery wastewater treatment. Denitrification efficiency and the effects of the nitrified effluent on acidification was investigated by recycling the nitrified effluent to the acidogenic reactor. Recycle of the nitrified effluent to the acidogenic reactor enhanced the conversion efficiency of the influent COD into volatile fatty acids(VFAs) in the TPAD-BNR system treating the piggery wastewater. Acidification rate of the acidogenic sludge acclimated with the nitrified effluent showed 6 times higher than that acclimated without it. VFA could be used for denitrification as carbon sources, however, nitrate could enhance acidification activity in the acidogenic reactor. VFA production rate was affected on the COD/Nitrate(COD/N) ratio, however, it depended much more whether the acidogenic sludge acclimated with nitrate or not. Denitrification with the acidogenic sludge acclimated without nitrified effluent followed zero-order reaction and the reaction rate constants were in the range of 1.31$\sim$1.90 mg/L$\cdot$h. Denitrification reaction rate constants of the acidogenic sludge acclimated with nitrified effluent were 3.30 mg/L$\cdot$h that showed almost twice of them evaluated from the previous tests. The stoichiometric ratios of utilized COD to removed nitrate showed similar in both tests which were in the range of 5.1$\sim$6.4 at COD/N ratio of 10.

Characteristics of Chlorination Byproducts Formation of Amino Acid Compounds (아미노산 성분에서의 염소 소독부산물 생성 특성)

  • Son, Hee-Jong;Choi, Young-Ik;Bae, Sang-Dae;Jung, Chul-Woo
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.5
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    • pp.332-340
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    • 2009
  • This study was conducted to analyze and determine formation potentials for chlorination disinfection by-products (DBPs) from twenty amino acid compounds with or without $Br^-$. Two of twenty amino acid compound were tryptophan and tyrosine that were relatively shown high for formation of trihalomethanes (THMs)/dissolved organic carbon (DOC) whether or not $Br^-$ presented. Other 18 compounds were shown low for formation of THMs/DOC whether or not $Br^-$ presented. Five amino acid compounds that were tryptophan, tyrosine, asparagine, aspartic acid and histidine were shown high for formation of haloacetic acids (HAAs)/DOC whether or not $Br^-$ presented. Although formation of dichloroacetic acid (DCAA) was dominated in asparagine, aspartic acid and histidine, trichloroacetic acid (TCAA) was dominated in tryptophan and tryptophan. The formation of haloacetnitriles (HANs)/DOC whether or not $Br^-$ presented was high in Aspartic acid, histidine, asparagine, tyrosine and tryptophan. Specially, aspartic acid was detected 660.2 ${\mu}$g/mg (HAN/DOC). Although the formation of chloralhydrate (CH)/DOC was shown high in asparagine, aspartic acid, histidine, methionine, tryptophan and tyrosine, the formation of Chloropicrin (CP)/DOC was low (1 ${\mu}$g/mg) in twenty amino acid compounds. The formations of THM, HAA and HAN were also investigated in functional groups of amino acids. The highest formation of THM was shown in amino acids compounds (tryptophan and tyrosine) with an aromatic functional group. Highest, second-highest, third-highest and fourth-highest functional groups for formation of HAA were aromatic, neutral, acidic and basic respectively. In order of increasing functional groups for formation of HAN were acidic, basic, neutral and aromatic.