• Applied Biological Chemistry
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• v.35 no.3
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• pp.173-178
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• 1992

A bacterium having CMCase activity was isolated form soil and identifed as a Pseudomonas sp YD-15. The optimum conditions for the production of CMCase were avicel 1.2%, yeast extract 0.5%, $KNO_3$ 0.06%, $K_2HPO_4$ 0.2%, $MgSO_4$ $7H_2O$ 0.15%, pH 8.0, $30^{\circ}C$ and 60 hours cultivation. The CMCase was purified 15.2 folds with 14ft yield through ammonium sulfate precipitation, DEAE-sepharose column chromatography and sephadex G-100 gel filtration chromatography. The optimum pH and temperature for the enzyme activity were 6.0 and $50^{\circ}C$, respectively. The enzyme was stable between pH 5.0 and 8.0, below $50^{\circ}C$. The molecular weight was calculated about 100,000 by SDS-polyacrylamide gel electrophoresis. $K_m$ value for CMC used as a substrate was 40 mg/ml.

• Microbiology and Biotechnology Letters
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• v.18 no.6
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• pp.599-606
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• 1990

A chitinase-producing bacterium, Aeromonas salmonicida YA7-625, was isolated from domestic seashore muds. The preferable medium composition for the production of chitinase was as follows: colloidal chitin 1.26% (w/v), tryptone 2.95% (w/v), $MgSO_4-7H_20$ 0.15% (w/v) and $K_2HP0_4$, 0.15% (w/v) (pH 8.5). The highest enzyme production was observed after cultivation of 48 hours at 27OC. The chitinase of Aeromonas salmonicida YA7-625 was purified successively by ammonium sulfate precipitation, affinity adsorption, hydroxylapatite column chromatography and gel filtration. The optimal temperature and pH for the activity of purified chitinase were $50^{\circ}C$ and 7.0, respectively. The molecular weight of purified chitinase was ca. 200,000 daltons and apparent Km value of it was 1.276 mglml on colloidal chitin.

• Analytical Science and Technology
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• v.12 no.3
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• pp.203-208
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• 1999

The ion-pair high performance liquid chromatographic elution behavior of salicylic acid and its derivatives was studied with measuring capacity factor, k', changing the concentration of ion-pairing reagent (tetrabutylammonium chloride, TBACl) in mobile phase. As a result, it was found that k' of the samples increase at pH 7.2 as the TBACl concentration increases. The derivatives of salicylic acid were separated each other at an optimum mobile phase condition which was found from the observation of the retention behavior. The optimum mobile phase condition was methanol solution($MeOH:H_2O_2$ 30:70) containing 20 mM TBACl for the determination of salicylic acid and methanol solution($MeOH:H_2O_2$ 20:80) containing 40 mM TBACl for p-aminosalicylic acid at pH 7.2. The method has been applied for the analysis of the contents of salicylic acid derivatives in an aspirin tablet and a tuberculosis curing agent.

• Korean Journal of Food Science and Technology
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• v.9 no.1
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• pp.31-35
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• 1977

As a study on the acid protease production by Rhizopus japonicus S-62, the culture conditions for the enzyme production and characteristics of the crude enzyme were investigated. The results are summarized as follows: 1. The optimum conditions for solid culture on wheat bran were 48 hrs of culture period and $100{\sim}120%$ addition of tap water. 2. Of the several media, wheat bran medium was the most excellent in the enzyme production. 3. The addition of sucrose, fructose, $NH_4Cl$ and $NaH_2PO_4$ on wheat bran, respectively, increased largely the enzyme production. 4. The optimum pH for the enzyme action was pH $2.4{\sim}2.6$, the optimum temperature was about $40^{\circ}C$, and the stable pH range was $pH\;2.5{\sim}5.0$, the enzyme was stable below $40^{\circ}C$ and was inactivated abruptly above $40^{\circ}C$.

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.51-55
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• 2003

To develop environment-friendly biofertilizer solubilizing insoluble phosphates, a bacterium possessing a high ability to solubilize $Ca_{3}(PO_{4})_{2}$) was isolated from the rhizosphere of peas. On the basis of its morphological, cultural, physiological characteristics, and Vitek analysis, this bacterium was identified as Pantoea agglomerans. The optimal medium composition and cultural conditions for the solubilization of insoluble phosphate by P. agglomerans R-38 were 3% of glucose.0.1% of TEX>$NH_{4}NO_{3}$, 0.02% of $MgSO_{4}\cdot\7H_{2}O$, and 0.06% of $CaCl_{2}\cdot\2H_{2}O$ along with initial pH 7.5 at $30^{\circ}C$. The highest soluble phosphate production under optimum condition was 898 mg/L after 5 days of cultivation. The solubilization of insoluble phosphate was associated with a drop in the pH of the culture medium. The strain produced soluble phosphate to the culture broth with the concentrations of 698 mg/L against CaHPO$_4$, 912 mg/L against hydroxyapatite, 28 mg/L against $FePO_{4}\cdot\4H_{2}O$, and 19 mg/L against $AIPO_{4}$, respectively.

• Current Research on Agriculture and Life Sciences
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• v.16
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• pp.45-54
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• 1998

A thermotolerant bacterium, Streptomyces thermocyaneoviolaceus which produced xylan-degrading enzymes, utilized excellently xylan of wheat bran by producing the enzymes in comparison with that of birchwood or oat spelts. Optimal enzyme production was achieved in WB medium containing 0.8% wheat bran, 0.06% yeast extract, 0.06% bactopeptone, 0.05% $MgSO_4{\cdot}7H_2O$, 0.05% $FeSO_4{\cdot}7H_2O$, 0.05% $KH_2PO_4$ and, 0.2% $K_2HPO_4$(pH 7.0) at $50^{\circ}C$ for 24 hrs. The optimal pH and temperature for the hydrolysis of xylan were pH 5.5 and $65^{\circ}C$, respectively. The enzyme activity was retained more than 80% at the range from pH 4.5 to pH 9.5 at $4^{\circ}C$ for 12 hrs and 94% on the heat-treatment at $65^{\circ}C$ for 1 hr. Xylobiose, xylotriose, xylose, and other xylooligosaccharides were produced as end products from hydrolysis of birchwood xylan by the xylanase of S. thermocyaneoviolceus.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.05a
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• pp.86-86
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• 2003

본 연구는 고추냉이(Wasabia japonica matsum)가 동치미의 발효 중 저장성에 미치는 영향을 알아보고 고추냉이의 최적사용량을 찾아내고자 하였다. 고구냉이는 무 무게에 대하여 0, 3, 5, 7, 9% 첨가하여 동치미를 담그어 1$0^{\circ}C$에서 50일간 발효시키면서 이화학적 특성을 알아보았다. pH의 경우 발효 초기에는 고추냉이 첨가한 처리구가 대조구에 비해 낮게 나타났다. 발효 10일 이후에는 대조구의 pH가 가장 낮게 나타났고 고추냉이 첨가량이 증가할수록 높은 pH를 나타내었다. (중략)

• Journal of the Korean Chemical Society
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• v.49 no.3
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• pp.325-328
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• 2005

• Journal of Life Science
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• v.14 no.4
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• pp.560-566
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• 2004

Agrocybe aegerita is Hymenomycetes fungus belonging to the order Agaricales and family of Bolbitiaceae. Much less is known about liquid culture of Agrocybe aegerita. Thus, the present study was to investigate the liquid cultural characteristics of Agrocybe aegerita my-celium. The optimal medium for the mycelial growth and density was ME medium, optimal tem-perature and initial pH were 25$\pm$1$^{\circ}C$ and 5.5, respectively. And optimal culture time for mycelial growth was 12 days. The modified optimal medium compositions were dextrin 3% (w/v), yeast extract 2% (w/w), MgSO$_4$0.05% (w/v), and KH$_2$PO$_4$0.15% (w/v). Under optimal culture conditions, the mycelial growth of modified optimal medium was higher than that of ME medium.

• KSBB Journal
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• v.13 no.4
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• pp.399-403
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• 1998

This study was carried out to optimize the concentration of Ca2+ and pH of fusion medium which affected electrofusion frequency of protoplasts isolated from Nicotiana tabacum L. (cv. BY4) mesophyll cells and callus. The protoplasts were electrofused in the fusion media containing two different Ca2+ concentrations and three different pH regions. Fusion frequency was lower in the fusion medium containing only 13% mannitol as osmotic stabilizer. However, higher degree of fusion frequency (47.3%) was observed in the fusion medium containing 50mM CaCl2 at pH 10.5 than any other conditions. Cell viability was decreased by Ca2+ and high pH treatment in the fusion media, while fusion frequency was increased. It is concluded that Ca2+ is involved in electrofusion of protoplasts.