• 미생물학회지
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• 제40권2호
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• pp.100-103
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• 2004

Inonotus mikadoi IMSNU 32058의 최적 균사생장을 위한 배양학적 특성 및 세포효소 활성의 최적 조건을 조사하였다. 균사 생장을 위한 최적온도는 $27^{\circ}C$였고, 실험한 pH 범위중pH 4.5에서 최적균사 생장을 나타내었다. 사용된 복합배지 중 malt extract media (MEM)와Phellinus igniarius media (PIM)에서 가장 좋은 균사 생장을 나타내었다. 최소배지로써 Czapek-Dox 한천배지를 사용하여 탄소원으로 단당류, 이당류 및 다항류를 침가하였을 때 xylose, raffinose 및 carboxymethyl cellulose (CMC)에서 가장 좋은 생장을 나타내었다. 일반적으로 유기질소원이 무기질소원보다 생장을 더 촉진하였다. 유기질소원으로는 yeast extract, soytone, proteose peptone 및 bacto peptone을 사용하였을 때 균사생육이 우수하였다. 무기질소원으로는 ammonium sulfate를 사용했을 때 균사생육이 촉진되었으며, 가장 우수한 비타민원은 p-aminobenzoic acid (PABA)이었다. MEM 액체(pH 4.5) 배지를 이용하여 $27^{\circ}C$에서 5일간 배양하였을 때, I. mikadoi의 균사외 분비효소 및 균사내 효소의 활성도를 측정하였다. 균사내 분비 효소중 laccase 의 활성도가 다른 효소에 비해 상대적으로 높았다. 균사외 분비 효소도 균사내 분비효소와 마찬가지로 laccase의 활성도가 다른 효소에 비해 상대적으로 높았으며 protease, chitinase 그리고 lipase의 활성도는 낮거나 없었다.

• Journal of Microbiology and Biotechnology
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• 제32권5호
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• pp.630-637
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• 2022

The objective of this study was to optimize industrial-grade media for improving the biomass production of Weissella cibaria JW15 (JW15) using a statistical approach. Eleven variables comprising three carbon sources (glucose, fructose, and sucrose), three nitrogen sources (protease peptone, yeast extract, and soy peptone), and five mineral sources (K₂HPO₄, potassium citrate, ⳑ-cysteine phosphate, MgSO₄, and MnSO₄) were screened by using the Plackett-Burman design. Consequently, glucose, sucrose, and soy peptone were used as significant variables in response surface methodology (RSM). The composition of the optimal medium (OM) was 22.35 g/l glucose, 15.57 g/l sucrose, and 10.05 g/l soy peptone, 2.0 g/l K₂HPO₄, 5.0 g/l sodium acetate, 0.1 g/l MgSO₄·7H₂O, 0.05 g/l MnSO₄·H₂O, and 1.0 g/l Tween 80. The OM significantly improved the biomass production of JW15 over an established commercial medium (MRS). After fermenting OM, the dry cell weight of JW15 was 4.89 g/l, which was comparable to the predicted value (4.77 g/l), and 1.67 times higher than that of the MRS medium (3.02 g/l). Correspondingly, JW15 showed a rapid and increased production of lactic and acetic acid in the OM. To perform a scale-up validation, batch fermentation was executed in a 5-l bioreactor at 37℃ with or without a pH control at 6.0 ± 0.1. The biomass production of JW15 significantly improved (1.98 times higher) under the pH control, and the cost of OM was reduced by two-thirds compared to that in the MRS medium. In conclusion, OM may be utilized for mass producing JW15 for industrial use.

• 한국식품영양과학회지
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• 제33권2호
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• pp.439-442
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• 2004

재래식 된장으로부터 혈전용해능과 $\beta$-glucosidase효소를 생산하는 미생물을 분리하였으며, 분리한 균의 형태학적, 생화학적인 분류를 수행하여 Bacillus속으로 동정하였으며, Bacillus sp. KHI-15로 명명하였다 그리고 분리한 균주의 효소생산을 위한 배지조건과 배양조건을 측정하였다. 선발균주는 2% glucose, 0.5% yeast extract, 0.1% calcium chloride의 최적 배지에서 최대의 효소생산을보였다. 초기 pH7∼8과 4$0^{\circ}C$에서는 혈전용해능이 최대를 보였으며, 초기 pH6∼8과 30∼4$0^{\circ}C$에서는 $\beta$-glucosidase 효소활성의 생산이 가장 높았다.

• 한국미생물·생명공학회지
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• 제17권5호
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• pp.468-474
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• 1989

Pseudomonas delafieldii이 다당류 생산을 위한 배양조건을 검토하였다. 최적 배지조성은 glucose 25g/$\ell$, peptone 2.06 g/$\ell$, yeast extract 0.5g/$\ell$, KH$_2$PO$_4$2g/$\ell$, MgSO$_4$2g/$\ell$, CaCO$_3$2.5g/$\ell$이며 교반속도는 300rpm, 온도는 30도, pH는 6.5이었다. 이 조건에서는 flask culture를 할 경우 5.91g/$\ell$가 생산되며 이 때 수율은 23.65%, overall productivity는 50.98mg/g/h이었다.

• Journal of Microbiology
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• 제34권4호
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• pp.363-369
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• 1996

As basic study to evaluate the treatability of oil-contaminated environment with bacteria, isolation and characterization of crude oil-degrading bacterium were carried out. A bacterial strain SH-14 capable of degrading crude oil was isolated from contaminated soils by enrichment culture technique and identified as Acinetobacter sp. by morphological, cultural and biochemical characteristics, and so named Acinetobacter sp. SH-14. The optimal medium composition and cultural conditions for the growth and emulsification of crude oil by Acinetobacter sp. SH-14 used were crude oil of 2.0%, $KNO_3$ of 0.2%, $K_2HPO_4$ of 0.05%, and $MgSO_4\;{\cdot}\;7H_2O$ of 1.0%, along with initial pH 7.0 at $30^{\circ}C$. Acinetobacter sp. SH-14 showed to be resistant to chloramphenicol and utilized various hydrocarbons such as dodecane, hexadecane, isooctane, cyclo-hexane etc., as a sole carbon source. Acinetobacter sp. SH-14 harbored a single plasmid. By agarose gel electrophoresis and curing experiment it was found that the genes for crude oil components degradation were encoded on the plasmid.

• 한국식품과학회지
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• 제21권5호
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• pp.619-623
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• 1989

토양으로부터 분리 동정된 Pseudomonas mendocina의 다당류 생산조건을 검토하였다. 최적 배지조성은 Sucrose 23.75g/L, $(NH_4)_2SO_4$ 1.57g/L, Yeast extract 0.5g/L, $KH_2PO_4\;2.0g/L,\;MgSO_4.\;7H_2O\;1.0g/L,\;CaCO_3$ 2.5g/L이었으며, 최적 pH 및 배양온도는 6.5 및 $30^{\circ}C$이었다. 이 조건에서 다당류의 생산량은 5.98g/L이며 대당 수율은 25.18%, 비생산속도는 32.83mg/g-cell/h이었다.

• KSBB Journal
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• 제13권4호
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• pp.343-351
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• 1998

About 75 strains which utilize cholesterol as sole carbon and energy source were isolated from 10 samples of Kimchi and 18 samples of fermented fish food (2 Ojingo-jeots, salt-fermented squid ; 5 Changran-jeots, salt-fermented pollack tripe ; 5 Myungran-jeots, salt-fermented Alaska pollack roe ; 3 Gajami-sikhae-jeots, fermented flat fish ; 2 Gul-jeots, salt-fermented oyster ; a Juneo-jeots, salt-fermented shad). Among them tested, the 3T6-5Mj strain isolated from Changran-jeot showed the highest activity on cholesterol degradation. The optimal composition of medium for the producing cholesterol degradation enzyme by 3T6-5Mj strain was 1.0 g/L NH4NO3, 1.0 g/L K2HPO4, 0.1 g/L MgSO4.7H2O, 1.0 g/L FeSO4.7H2O, 1 g/L NaCl, 5 g/L Trypton, 1 g/L Cholesterol, and 5 g/L Maltose at 30$^{\circ}C$, pH 7.5, and the enzyme production reached a maximum level at 140 hours of cultivation.

• Membrane and Water Treatment
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• 제6권4호
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• pp.277-292
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• 2015

The extraction of lactic acid by an emulsion liquid membrane (ELM), in batch and continuous mode, has been reported. On the basis of preliminary experiments, the optimum composition of the organic phase (membrane) is determined. When the SPan 80 is used as surfactant, the emulsion breakage exceeds 50%, but only 10% is obtained when the ECA4360 is used. The effects of surfactant, carrier and solute concentrations, phase volume ratio, and stirring speed on the extraction yield were examined and optimized. Surfactant, carrier and diluent used were ECA4360, trilaurylamine (TLA) and dodecane, respectively; 2-ethylhexane-1,3-diol (EHD) is used as a co-surfactant. Under optimal conditions, emulsion breaking is very low and the swelling is kept at its lowest level. Under the pH conditions of fermentation medium, the extraction yield is lower. A mixer-settler continuous system was used for testing these conditions. The residence time, the number of extraction stages and the stability of the emulsion were studied and optimized. The extraction yield obtained exceeds 90%.

• Journal of Applied Biological Chemistry
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• 제58권1호
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• pp.81-88
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• 2015

Bacillus pumilus IJ-1의 생물계면활성제 생산을 위한 배지 조성의 특성을 조사하기 위하여 다양한 탄소원, 질소원 및 무기염이 미치는 영향을 검토하였다. 그 결과 B. pumilus IJ-1은 0.5%(w/v) tryptone을 첨가하여 배양하였을 때 가장 많은 생물계면활성제를 생산하였다. B. pumilus IJ-1은 0-10% (w/v)의 NaCl 농도와 pH 5-10, $20-45^{\circ}C$의 환경에서 생장이 가능하였다. 그리고 생물계면활성제 생산은 pH 9.0의 초기 배지에서 $20^{\circ}C$, 72시간 동안 배양했을 때 최대였으며, 이러한 배양 조건 하에서 얻어진 배양액의 표면장력은 27.0 dyne/cm이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.139-147
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• 1999

Peptides are formed in the rumen as the result of microbial proteinase activity. The predominant type of activity is cysteine ptoteinase, but others, such as serine proteinases, are also present. Many species of protozoa, bacteria and fungi are involved in ptoteolysis; large animal-to-animal variability is found when proteinase activities in different animals are compared. The peptides formed from proteolysis are broken down to amino acids by peptidases. Different peptides are broken down at different rates, depending on their chemical composition and particularly their N-terminal structure. Indeed, chemical addition to the N-terminus of small peptides, such as by acetylation, causes the peptides to become stable to breakdown by the rumen microbial population; the microorganisms do not appear to adapt to hydrolyse acetylated peptides even after several weeks exposure to dietary acetylated peptides, and the amino acids present in acetylated peptides are absorbed from the small intestine. The amino acids present in some acetylated peptides remain available in nutritional trials with rats, but the nutritive value of the whole amino acid mixture is decreased by acetylation. The genus Prevotella is responsible for most of the catabolic peptidase activity in the rumen, via its dipeptidyl peptidase activities, which release dipeptides rather than free amino acids from the N-terminus of oligopeptides. Studies with dipeptidyl peptidase mutants of Prevotella suggest that it may be possible to slow the rate of peptide hydrolysis by the mixed rumen microbial population by inhibiting dipeptidyl peptidase activity of Prevotella or the rate of peptide uptake by this genus. Peptides and amino acids also stimulate the growth of rumen microorganisms, and are necessary for optimal growth rates of many species growing on tapidly fermented substrates; in rich medium, most bacteria use pre-formed amino acids for more than 90% of their amino acid requirements. Cellulolytic species are exceptional in this respect, but they still incorporate about half of their cell N from pre-formed amino acids in rich medium. However, the extent to which bacteria use ammonia vs. peptides and amino acids for protein synthesis also depends on the concentrations of each, such that preformed amino acids and peptides are probably used to a much lesser extent in vivo than many in vitro experiments might suggest.