• Microbiology and Biotechnology Letters
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• v.8 no.3
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• pp.181-191
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• 1980

For the purpose of studies on the citric acid production, some experiments were carried out with isolated strains. The results obtained were as follows. 1) The optimal culture media of the strain M-80 in surface culture contained 140g of sucrose, 3.0g of (N $H_4$)$_2$S $O_4$, 1.5g of K $H_2$P $O_4$, 0.2g of MgS $O_4$.7$H_2O$, 3.0mg of F $e^{++}$, 1.0mg of Z $n^{++}$, 0.5N HCI to a pH of 5.0 and distilled water to 1.0 liter; and that of the strain M-315 in surface culture contained 140g of sucrose, 2.0g of N $H_4$N $O_3$, 1.0g of K $H_2$P $O_4$, 0.25g of MgS $O_4$. 7$H_2O$, 2.0mg of F $e^{++}$, 2.0mg of Z $n^{++}$, 0.05mg of C $u^{++}$, 0.5N HCI to a pH of 4.5 and distilled water to 1.0 liter. While that of the strain M-315 in submerged culture contained 140g of sucrose, 2.5g of N $H_4$N $O_3$, 1.5g of K $H_2$P $O_4$, 0.3g of MgS $O_4$. 7$H_2O$, 3.0mg of F $e^{++}$, 0.1mg of C $u^{++}$, 0.5N HCI to a pH of 4.5 and distilled water to 1.0 liter. The optimal temperature and size of inoculum were mostly 28-3$0^{\circ}C$, 10$^{7}$ -10$^{8}$ spores/50ml, respectively. 2) Through the course of citric acid production, the growth of strains had nearly been completed, pH value was rapidly decreased below 2.0 and the content of sugar was also reduced, while the accumulation of citric acid in media was remarkably begun in about 3-4 days. The yields of citric acid generally reached the maximum level in 8-10 days in surface or submerged fermentation process. 3) Methanol was effective citric acid production when they were added to fermentation media. In the case of surface culture, by addition of 2％ (strain M-80), 3％ (strain M-315), the yields of citric acid was increased 6.5％, 20.6%, respectively and 5.0% yield was increased by addition of 3% methanol in submerged culture media of the strain M-315. 4) Chromatography analysis of culture broth after fermentation under optimal culture conditions detected that the majority of acid in media was citric acid. 72.1mg/ml, 98.1mg/ml, of citric acid were determined in surface culture media by strains of M-80, M-315, and 59.8 mg/ml of citric acid was contained in the submerged culture media by the strain M-315. strain M-315.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.594-597
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• 2001

RhodopseudolllOllas palustris P4 was studied for $H_2$ production from glucose in batch culture. Important conditions studied include phosphate concentration, initial pH, temperature, glucose concentration, and gas-phase replacement. Optimal $H_2$ production was observed at 60 - 300 mM of phosphate and 7.8 - 8.6 of initial pH. The effect of culture temperature was negligible When glucose concentration increased from 0.1 to 5% (w/v), $H_2$ production increased up to 2% and remained constant thereafter. Intermittent purging of the reaction botlle with Ar gas stimulated the Hl production by alleviating the inhibition by $H_2$. The maximum productivity was 111.1 ml $H_2$/h-1.

• KSBB Journal
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• v.20 no.1 s.90
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• pp.66-70
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• 2005

Optimization of culture conditions for pigment production of Monascus purpureus P-57 mutant was investigated in liquid culture. The optimum composition of medium for the pigment production was $4\%$ rice power, $0.1\%$ beef extract, $0.03\%$ glutamic acid, $0.1\%\;MgSO_4{\cdot}7H_2O,\;0.25\%\;KH_2PO_4$, the optimum initial pH was 5.0. And the optimum culture conditions was at $30^{\circ}C$ for 8 days under 150 rpm with shaking. M. purpureus P-57 mutant produced the highest pigment as 356.04 units at red pigment and as 268.20 units at yellow pigment, and produced high cell mass as 15.00 g/L in liquid culture under the optimum conditions.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.189-194
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• 1998

The experiment was tried to identify culture media which was suitable for seed germination and seedling growth of wild orchids, Calanthe discolor and Habenaria radiata. When seeds of Calanthe discolor, which was treated with ultrasonics for 30 minutes, were sowed in Murashige and SKoog(MS) medium, germination was much more promoted than other treatments. Seedling of C. discolor grew more rapidly in 3g/L Hyponex and 2g/L tryptone(H$_3$T$_2$) medium and 3g/L Hyponex and 2g/L peptone(H$_3$P$_2$) medium, especially in H$_3$P$_4$ medium among those media, pseudobulb became more corpulent. Habenaria radiata, whose tubers were obtained from seedlings, were sprouted more vigorously in 3g/L Hyponex and 1g/L peptone(H$_3$P$_1$) medium and 1g/L Hyponex and 2g/L peptone(H$_1$P$_2$) medium; but multiplication of tubers, growth of daughter tubers and its corpulence were well established in 1g/L Hyponex and 2g/L peptone(H$_1$P$_2$) medium.

• YAKHAK HOEJI
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• v.36 no.4
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• pp.390-396
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• 1992

Streptomyces minoensis DMCJ-144 isolated from soil produces the ${\alpha}-amylase$ inhibitor. Optimum culture conditions for ${\alpha}-amylase$ inhibitor production of the strain were determined in this experiment. The optimum composition of the culture medium was studied by supplementing various carbon sources, nitrogen sources, vitamins, and metal salts to the basal medium containing 1% glucose, 0.1% asparagine, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $K_2HPO_4$, 0.005% NaCl. Other culture conditions such as the culture temperature, initial pH of the medium, aeration, and culture time were also investigated. When the strain was cultured in a 100 ml flask containing 20 ml of 2% glucose, 0.5% beef extract, 0.0002% riboflavin, 0.0002% thiamine HCI, 0.01% $ZnCl_2$, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $CuSO_4{\cdot}5H_2O$, 0.005% NaCl, pH 7.2, 180 rpm at $30^{\circ}C$, the maximum production of the ${\alpha}-amylase$ inhibitor was observed after 5 days of the cultivation.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.207-210
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• 2000

Pseudomonas oleovorans was cultivated to produce medium chain length polyhydroxyalkanoates (MCL-PHA) fram octanoic acid and ammonium nitrate as carbon and nitrogen source, respectively, by a pH-stat fed-batch culture technique. The octanoate concentration of the culture broth was maintained below 4 g/L by feeding the mixture of octanoic acid and ammonium nitrate when the culture pH rose above high limit. The effect of the ratio of octanoic acid to ammonium nitrate (C/N ratio) in the feed on the PHA production was examined. The final cell concentrations of 62.5, 54.7, and 9.5 g/L, PHA contents of 62.9, 75.1, and 67.6% of dry cell weight, and productivities of 1.03, 0.632, and 0.161 g/L/h were obtained when the C/N ratio in the feed were 10, 20, and 100 g octanoic acid/g ammonium nitrate, respectively.

• BMB Reports
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• v.40 no.3
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• pp.333-340
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• 2007

Gene encoding cyclodextrin glycosyltransferase (CGTase), from thermotolerant Paenibacillus sp. T16 isolated from hot spring area in northern Thailand, was cloned and expressed in E. coli (JM109). The nucleotide sequences of both wild type and transformed CGTases consisted of 2139 bp open reading frame, 713 deduced amino acids residues with difference of 4 amino acid residues. The recombinant cells required 24 h culture time and a neutral pH for culture medium to produce compatible amount of CGTase compared to 72 h culture time and pH 10 for wild type. The recombinant and wild-type CGTases were purified by starch adsorption and phenyl sepharose column chromatography and characterized in parallel. Both enzymes showed molecular weight of 77 kDa and similar optimum pHs and temperatures with recombinant enzyme showing broader range. There were some significant difference in pH, temperature stability and kinetic parameters. The presence of high starch concentration resulted in higher thermostability in recombinant enzyme than the wild type. The recombinant enzyme was more stable at higher temperature and lower pH, with lower $K_m$ for coupling reaction using cellobiose and cyclodextrins as substrates.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.380-383
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• 2000

The effect of on the cell growth, the elaboration of pullulan, the morphology and were the effect of on the molecular weight of pullulan were investigated. A. pullulans showed maximum pullulan production when initial pH 6.5 was 11.98 g/l in shake-flask culture. In batch culture, the maximum pullulan production of 15.16 g/l was obtained at an aeration rate of 0.5 vvm. The mixture of yeast-like form and mycelial form of cells was found at the constant pH 4.5, at which condition, the elaboration of pullulan was high, about 13.31 g/l. However, pullulan with its higher molecular weight (>1,000,000) was produced at the constant pH 6.5.

• The Research Journal of the Costume Culture
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• v.13 no.2 s.55
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• pp.248-254
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• 2005

In this study, wool fabric specimens were pre-mordanted using Sn, Al, Cu, Cr, and Fe, and subsequently dyed using cochineal, maintaining the pH of the dye bath constant using pH buffer solutions of 4, 5, 6, 7, and 8. In the case of wool fabric specimen, regardless of the type of mordanting agents, peak dye-uptake amount was obtained at the acidic region, pH 4, and above pH 6, the dye-uptake amount decreased remarkably. Differing from the cotton fabric case, the dyed wool fabric specimen exhibited red shade even in the case of non-mordanting, at the region of pH values of 4 and 5. It is presumed that in the acidic dye bath the effect of cationic amine group present in the structure of wool fiber molecules took place. The amount of color difference, among the mordanting agents, due to the increase of pH value, was highest for the Fe mordanting case. It seems, therefore, that the Fe mordanting is affected most by the pH value.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1381-1388
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• 2012

An in vitro experiment was conducted to examine the effects of defaunation (removal of protozoa) on ruminal fermentation characteristics, $CH_4$ production and degradation by rumen microbes when incubated with cereal grains (corn, wheat and rye). Sodium lauryl sulfate as a defaunation reagent was added into the culture solution at a concentration of 0.000375 g/ml, and incubated anaerobically for up to 12 h at $39^{\circ}C$. Following defaunation, live protozoa in the culture solution were rarely observed by microscopic examination. A difference in pH was found among grains regardless of defaunation at all incubation times (p<0.01 to 0.001). Defaunation significantly decreased pH at 12 h (p<0.05) when rumen fluid was incubated with grains. Ammonia-N concentration was increased by defaunation for all grains at 6 h (p<0.05) and 12 h (p<0.05) incubation times. Total VFA concentration was increased by defaunation at 6 h (p<0.05) and 12 h (p<0.01) for all grains. Meanwhile, defaunation decreased acetate and butyrate proportions at 6 h (p<0.05, p<0.01) and 12 h (p<0.01, p<0.001), but increased the propionate proportion at 3 h, 6 h and 12 h incubation (p<0.01 to 0.001) for all grains. Defaunation increased in vitro effective degradability of DM (p<0.05). Production of total gas and $CO_2$ was decreased by defaunation for all grains at 1 h (p<0.05, p<0.05) and then increased at 6 h (p<0.05, p<0.05) and 12 h (p<0.05, p<0.05). $CH_4$ production was higher from faunation than from defaunation at all incubation times (p<0.05).