• 제목/요약/키워드: Incubation Temperature

검색결과 838건 처리시간 0.028초

Xylanase생산성 Bacillus sp. GS의 분리 및 동정 (Isolation and identification of Bacillus sp, GS Producing Xylanase)

  • 안준배;박헌국;이계호
    • 한국식품영양학회지
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    • 제7권1호
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    • pp.8-15
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    • 1994
  • To utilize hemicellulosic biomass efficiently, the microorganism producing xylanase was isolated from fermented sawdust. It was a Gram positive, aerobic and rod shape bacterium. It had endospore and secreted strong hydrolases, such as amylase and protease. Through morphological, cultural and physiological tests, it was identified as Bacillus sp. GS. To increase the productivity of xylanase from Bacillus sp. GS, the enzyme production medium was optimized. The composition of the medium and incubation conditions were like follows xylan 1.25%, yeast extract 0.1%, NaN030.2%, K2HP04 0.1%, MgSO4 0.02%, mineral salt 0.005%, pH 6.5, incubation temperature 37$^{\circ}C$.

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양파검은무늬병균의 포자발아에 마치는 물리적 요인 (Physical Factors in Relation to Conidial Germination in Alternaria porri, the Incitant of Purple Blotch of Onion)

  • R.B.L. 굽타;V.N. 파닥;O.P. 베르마
    • 한국응용곤충학회지
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    • 제24권3호
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    • pp.135-139
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    • 1985
  • Influence of temperature, relative humidity, spore washing and spore drying on conidial germination of Alternaria porri(Ell.) Cif. was studied. Maximum conidial germination occurred at 100% relative humidity prevailing for 6 hours or more at $25^{\circ}C$. Conidial germination decreased with increase in number of spore washings. Drying of conidia for more than half an hour caused significant decrease in germination. In all the experiments, conidial germinatio increased with increase in incubation period.

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Benzoic Acid Production with Respect to Starter Culture and Incubation Temperature during Yogurt Fermentation using Response Surface Methodology

  • Yu, Hyung-Seok;Lee, Na-Kyoung;Jeon, Hye-Lin;Eom, Su Jin;Yoo, Mi-Young;Lim, Sang-Dong;Paik, Hyun-Dong
    • 한국축산식품학회지
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    • 제36권3호
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    • pp.427-434
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    • 2016
  • Benzoic acid is occasionally used as a raw material supplement in food products and is sometimes generated during the fermentation process. In this study, the production of naturally occurring yogurt preservatives was investigated for various starter cultures and incubation temperatures, and considered food regulations. Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus reuteri, Lactobacillus plantarum, Bifidobacterium longum, Bifidobacterium lactis, Bifidobacterium bifidum, Bifidobacterium infantis, and Bifidobacterium breve were used as yogurt starter cultures in commercial starters. Among these strains, L. rhamnosus and L. paracasei showed the highest production of benzoic acid. Therefore, the use of L. rhamnosus, L. paracasei, S. thermophilus, and different incubation temperatures were examined to optimize benzoic acid production. Response surface methodology (RSM) based on a central composite design was performed for various incubation temperatures (35-44℃) and starter culture inoculum ratios (0-0.04%) in a commercial range of dairy fermentation processes. The optimum conditions were 0.04% L. rhamnosus, 0.01% L. paracasei, 0.02% S. thermophilus, and 38.12℃, and the predicted and estimated concentrations of benzoic acid were 13.31 and 13.94 mg/kg, respectively. These conditions maximized naturally occurring benzoic acid production during the yogurt fermentation process, and the observed production levels satisfied regulatory guidelines for benzoic acid in dairy products.

Low incubation temperature successfully supports the in vitro bovine oocyte maturation and subsequent development of embryos

  • Sen, Ugur;Kuran, Mehmet
    • Asian-Australasian Journal of Animal Sciences
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    • 제31권6호
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    • pp.827-834
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    • 2018
  • Objective: The aim of this study was to compare the effects of $36.5^{\circ}C$ and $38.5^{\circ}C$ incubation temperatures on the maturation of bovine oocytes and developmental competence of embryos. Methods: In experiment 1, oocytes were maturated in bicarbonate-buffered TCM-199 for 22 hours in a humidified atmosphere of 5% $CO_2$ in the air at either $36.5^{\circ}C$ or $38.5^{\circ}C$ and nuclear maturation status were determined. In experiment 2, in vitro fertilized oocytes were allocated randomly into synthetic oviductal fluid medium with or without a mixture of 1 mM L-glutathione reduced and 1,500 IU superoxide dismutase and cultured in a humidified atmosphere of 5% $CO_2$, 5% $O_2$, and 90% $N_2$ in the air at $38.5^{\circ}C$ for 8 days. Results: There were no significant differences between incubation temperatures in terms of oocyte maturation parameters such as cumulus expansion, first polar body extrusion and nuclear maturation. Incubation temperatures during in vitro maturation had no effects on developmental competence of embryos, but supplementation of antioxidants increased (p<0.05) developmental competence of the embryos. Blastocysts from oocytes matured at $38.5^{\circ}C$ had comparatively higher inner cell mass, but low overall and trophectoderm cell numbers (p<0.05). Conclusion: The results of present study showed that maturation of bovine oocytes at $36.5^{\circ}C$ may provide a suitable thermal environment for nuclear maturation and subsequent embryo development.

Modified Drum Priming and Exogenous Application of 24-Epibrassinolide (24-EBL) for Enhancing Germination under High Temperature Condition in Lettuce Seeds

  • Kang, Won Sik;Kim, Min Geun;Kim, Du Hyun
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2018년도 추계학술대회
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    • pp.86-86
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    • 2018
  • This study was conducted to investigate the effects of modified drum priming and 24-Epibrassinolide (24-EBL) treatment to improve the seed quality for export. 40, 50 and 60% seed moisture content (SMC) of hydrated seeds were incubated for 16 and 24 h in a container with a relative humidity of 99% at 26 rpm for a modified drum priming treatment. The treated seeds were sown at $20^{\circ}C$ and $30^{\circ}C$ (12/12h, light/dark) with four replications of 25 seeds on pleated paper. The seeds were hydrated with water or 24-EBL solutions of $10^{-7}$, $10^{-8}$ and $10^{-9}M$, respectively. The germination of the modified drum primed seeds (24 h incubation after 60% SMC hydration) improved to 1.6 days mean germination time (MGT) and $46%{\cdot}day^{-1}$ germination rate (GR), while the untreated seeds showed 2.1 days MGT and $28%{\cdot}day^{-1}$ GR. The modified drum priming (60% SMC and 24 h incubation with $10^{-9}M$ 24-EBL) showed improved results in MGT (1.8 days) and GR (55%) at $20^{\circ}C$, whereas untreated seeds showed 2.3 days MGT and 44% GR. Under $30^{\circ}C$, germination of modified drum primed seeds was significantly improved in GP (80%), GR ($31%{\cdot}day^{-1}$), HS (55%) and MGT (3.3 days), however, untreated seeds showed decreased GP (27%), GR ($22%{\cdot}day^{-1}$), HS (55%) and MGT (4.8 days). This study showed that the germination of lettuce seeds is enhanced by 24 h drum incubation with 24-EBL and this method can be used effectively to achieve the benefits of early germination and uniform seedling development. In addition, these treatments circumvent thermo-dormancy of lettuce seed and have a possibility of high-quality and environment-friendly seed processing.

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표고골목 해균인 주홍꼬리버섯을 방제하기 위한 저항성 표고균주 선발 (Control of Diatrype stigma occurred on the bed-log of Shiitake by resistant Shiitake strains)

  • 이봉훈;박원철;가강현;윤갑희;박현;차병진
    • 한국버섯학회지
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    • 제3권3호
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    • pp.109-114
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    • 2005
  • 표고골목 해균인 주홍꼬리버섯을 방제하기 위해 저항성 표고균주 선발을 시도하였다. 저항성 표고균주 선발 시험에서, 사용된 77개 균주 중 67개 균주가 저항력을 가지는 것으로 확인되었다. 이들 67개 균주 중 KFRI 5를 포함한 13개 균주가 주홍꼬리버섯균의 접근을 막는데 가장 큰 영향을 미쳤고 KFRI 180을 포함한 7개 균주가 주홍꼬리버섯의 영역으로 가장 많이 침범했다. 교잡을 통해 만든 31개 균주 중 KFRI 537을 포함한 8개 균주가 주홍꼬리버섯균의 접근을 막는데 가장 큰 영향을 미쳤고 KFRI 545를 포함한 4개 균주가 주홍꼬리버섯의 영역으로 가장 많이 침범했다. 온도와 접종순서의 변화에 따른 각 균주의 저항력 차이를 확인하기 위해 PDA 평판배지와 상수리나무톱밥을 넣은 시험관배지를 사용했다. PDA 평판배지 시험결과, 대부분의 처리구에서 KFRI 137은 주홍꼬리버섯에 대해 뛰어난 접근 억제력을 보였고 KFRI 180은 뛰어난 침범력을 보였다. 교잡균인 KFRI 545, 546, 547은 모균주들인 KFRI 488과 405에 비해 높은 저항력을 보였다. 시험관배지 시험결과, 표고균과 주홍꼬리버섯균이 대치를 하는 시점부터 $25^{\circ}C$에 두었을 때 모든 균주가 높은 저항력을 나타냈다. KFRI 393은 $25^{\circ}C$에서 지속 배양할 때 다른 균주에 비해 높은 저항력을 나타냈다. 또한 모든 균주들에서, $25^{\circ}C$ 배양 후 두 균이 대치를 할 시기에 $14^{\circ}C$로 옮겨 배양한 처리구는 다른 처리구들에 비해 낮은 저항력을 보였다. 이때의 저항력 정도는 각 균주 최고치의 7-20%에 불과했다. 또한 KFRI 259는 PDA 평판배지에서와 달리, 주홍꼬리버섯의 영역을 침범했다.

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Effects of Processing Methods and Variety of Rapeseed Meal on Ruminal and Post Ruminal Amino Acids Digestibility

  • Chen, Xibin;Qin, S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권6호
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    • pp.802-806
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    • 2005
  • The objective of this study was to determine the effects of processing method and rapeseed variety on ruminal and intestinal protein digestibility of rapeseed meal in steers. Intestinal amino acid digestibility was assessed with an in situ ruminal incubation and precision-fed rooster bioassay. In this experiment one traditional rapeseed meal sample (sample A, prepress extraction) and three double low rapeseed meal samples (sample B, prepress extraction, sample C, screw press and sample D, low temperature press) were placed in polyester bags(8 cm${\times}$12 cm) and suspended in the ventral rumen of steers for 16 h. The residues of in situ incubations were intubated to roosters. Total excreta were collected for 48 h after incubation and then desiccated and amino acid concentrations were determined. Results showed that in ruminal incubation the degradation rate of amino acid and crude protein was higher for traditional rapeseed meal sample A than for double low rapeseed meal sample B, but was much lower than for double low sample C and D. In the group of double low rapeseed meal samples, sample D processed by low temperature press had the highest degradation rate of amino acids in the rumen. For all amino acids, the digestibility of the residual protein as measured by the precision-fed rooster bioassay tended to be lower for sample B than for sample A, which had the same processing method with sample B, and in the group of double low rapeseed meals, sample B had similar digestibility of amino acid in residual protein to sample D and higher than that of sample C. However, although the total amino acid availability involving the digestibility of amino acids in the rumen and rooster bioassay of double low rapeseed meal sample D (low temperature press) was higher than those of the other three samples by 7 to 9 percent, there were no significant differences. Results indicated that processing method markedly affected ruminal and post ruminal amino acid digestibility of rapeseed meal when the temperature exceeded 110$^{\circ}C$. Rapeseed meal that had a high content of fiber was not suitable for dry heat treatment at higher temperatures or the amino acids digestibility in rumen and total availability of amino acids could be reduced. Results also suggested the variety of rapeseed meal had no significant effect on the digestibility and availability of amino acids.

표고 톱밥재배용 균주의 육종과 재배특성에 관한 연구 (Studies on Breeding and Cultivation Characteristics of Lentinula edodes Strains for Sawdust Cultivation)

  • 유성열;박원철;구창덕;이봉훈
    • 한국균학회지
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    • 제37권1호
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    • pp.65-72
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    • 2009
  • 톱밥배지에 적합한 품종 구비 조건으로서 요구되는 신규성, 구별성, 균일성, 안정성에 대해 교잡균주제조에 따른 균사생장, 배양일수, 생산성, 온도형 등을 비교하여 톱밥배지에 적합한 균주육종을 시도하였다. 본 실험에서는 Di-mon교배법을 이용하여 이핵 균주 21개와 일핵 균주 2개 사이의 상호교배에서 19개의 새로운 균주를 만들었다. 이 가운데 균사생장과 목재 부후력이 활발한 10개 균주를 선발하였다. 이 선발된 균주들은 100일, 125일, 150일 등으로 배양일수를 달리하여 생산성 검정을 하였다. 그 결과 100일 처리에서 KFRI 960, 961, 962, 963, 964, 971, 973균주가 생산성이 우수하였으며, 125일 처리에서 KFRI 968, 970균주가 생산성이 우수하였다. 배양일수에 따른 생산성은 100일과 150일 처리사이에서 차이가 났다. 교배 온도형의 비교는 고온성 사이의 교배와 저온성과 고온성 사이의 교배, 아직 결정되지 않은 온도형과 고온성 간의 교배의 생산성차이는 없었으며, 중온성과 고온성과의 교배로 만들어진 균주들과는 생산성 차이가 났다. 교잡균주들의 온도형 분석은 고온성 균주가 다른 온도형에 비해 우성형질을 가졌다.

경주에서 분리된 탄저균에 대한 연구 (Investigation on Bacillus anthracis isolated from Kyong-Ju)

  • 이준규;이은미;차우양;김정화;김영환;이양수;김우현;정종식
    • 한국동물위생학회지
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    • 제18권1호
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    • pp.41-56
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    • 1995
  • The present study was conducted to investigate results of B. anthracis isolated from Anthrax in the Kyong-Ju of Feb. 12. 1994. 1. In biochemical feature, B. anthracis was a gram-positive rod, non-motility, sporulation, capsulation. It was positive in gelatinase, starch hydrolysis, glucose. But negative in urease, arabinose, mannitol, xylose. 2. B. anthracis grew well on B4 Br A TSA after incubation for 24 hours. The organisim grew well on BA, Br. A, NA, TSA after incubation for 72 hours. The media grew well on Br A instead of BA. 3. On 5% blood agar by laboratory animal, ${\beta}$ -hemolysis was produced from 36 hours to 48 hours incubation. There was perfect ${\beta}$-hemolysis after incubation for 48 hours. On the other side ${\beta}$-hemolysis was begun on 5% goat blood agar after incubation for 60 hours. 4. In the test of antimicrobial susceptibility, B. anthracis was very sensitive to AM, CF, TE, ENR, GM, AN, DFX, S, P, TYLO, N, KM, C, E, Lins+Sp, NN, CC, CFP, CB were sensitive one by one. B. anthracis was no-sensitive to L, XNL, TIA, CL, SXT 5. B. anthracis had never sensitivity to direct inoculation of rat and chicken, after subcutanous inj. It was very sensitive to mouse and goat, hamster, guinea pig, rabbit had a sensibility one by one. 6. The dead laboratory animal which had been inoculated with B. anthracis preserved at $37^{\circ}C$ incubation, B. anthracis didn't cultivate on non-dissected animal after 80 hours but cultivate on dissected animal after 360 hours. 7. The rapidly death could cause high concentration, died from 420 after S. C. 8. The blood smeared samples of hamster from inoculation with B. anthracis, spore germinated In 37$^{\circ}C$ after 5 hours, in $32^{\circ}C$ after 6 hours, in room temperature after 9 hours, in $-4^{\circ}C$ to $-20^{\circ}C$ after 10 hours. 9. B, anthracis inoculated to laboratory animal after SC or PO. Mice and rats feces didn't cultivated with B. anthracis after SC, but did cultivated with B. anthracis after PO. 10. In the test of disinfectant, B. anthracis was high effective to $HgC1_2$, formalin, effect phenol, cresol, but non-effect NaOH, ethanol.

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Transglutaminase를 첨가한 돈육 근원섬유단백질과 카제인염 혼합물의 배양온도와 시간에 따른 물성변화 (Rheological Properties of Pork Myofibrillar Protein and Sodium Caseinate Mixture as Affected by Transglutaminase with Various Incubation Temperatures and Times)

  • 황지숙;이홍철;진구복
    • 한국축산식품학회지
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    • 제28권2호
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    • pp.154-159
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    • 2008
  • 근육단백질과 카제인염 단백질간의 상호작용의 촉매제로서 TGase의 배양시간과 온도에 따른 물성효과를 측정하기 위하여 본 연구를 실시하였다. 돈육 등심부위의 근원섬유단백질을 추출하였고 배양온도는 $4^{\circ}C$, $37^{\circ}C$로, 배양시간은 0, 0.5, 2, 4시간으로 단백질의 열량분석, 점도, 겔 강도, 전기영동상 패턴의 변화를 측정하였다. 단백질열량변화는 각 단백질 별로 열량변화 패턴이 상이하게 나타났으며 근원섬유와 카제인염의 혼합액은 각각의 단백질 피크와 유사하게 나타났고 배양시간과 온도에 따라 차이를 보여 $4^{\circ}C$에 비하여 $37^{\circ}C$에서 열량변화의 차이가 크게 나타났다. 점도의 경우 배양하지 않은 것과 비교했을 때 $37^{\circ}C$에서 2시간 배양했을 때부터 유의적인 차이를 보이며 증가하였다. 근원섬유단백질을 4.5%의 농도로 가열에 의한 겔의 강도를 측정한 결과, 배양시간이나 온도에 따른 뚜렷한 차이를 보이지 않았다. 전기영동의 경우에도 $4^{\circ}C$$37^{\circ}C$의 배양의 경우 myosin heavy chain과 카제인 염 단백질 분획이 배양시간이 경과함에 따라 점차 감소하였고, 특히 $37^{\circ}C$에서 30분까지는 큰 변화를 나타내지 않았으나 2시간부터 32-34 kDa 분자량을 갖는 카제인 염단백질의 저분자의 밴드가 사라지고 고분자의 biopolymer를 형성하였다. 이상의 결과를 종합하면 $4^{\circ}C$보다 $37^{\circ}C$에서 단백질 분자간의 상호작용에 의한 TGase의 효과가 뚜렷하였으며 $37^{\circ}C$에서 2시간 이상 배양시 TGase에 의한 현저한 물성의 차이를 보인 것으로 평가된다.