• Korean Journal of Microbiology
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• v.14 no.2
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• pp.49-49
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• 1976

Enzyme activities, such as glucoamylase dextrinogenic amylase, cellulase, acid protase and neutral protease, of Rhizopus isolated from various substrates collected throughout South Korea are measured, and their enzyme activities are surveyed from taxonomical, ecological and physiological viewpoint. Effect of carbon sources and phytohormones on the amylalse production of Rhizopus are also measured. Among the 735 strains of Phizopus isolated, strain number 587 exhibiting most prominent dextrinogenic amylase and netral protease activity is selected as the best strain, and the strain number 673, 108, 329, 165 and 728 are seleted for their predominant cellulase, acid protease, glucoamylase, dextrinogenic amylase and neutral protease activities, respectively. R.acidus and R.nigricans which exhibited relatively higher callulalse activity, showed lower activities for both amylase. R.tritici exhibited higher protease activity. The relations between activities and various substrates of wild strains are not outstnading difference, although the strains isolated from inland region exhibited more or less higher amylase and cellulase activities, than those of coast region, generally. Lactose and dextrin are most effective carbon sources for glucoamylase and dextrinogenic amylase production of the Rhizopus niveus, respectively. Although all phytohormones tested are effective for production of amylase by the Rhizopus strains, except nicotinamide for glucoamylase production, biotin and ascorbate are most effective for dextrinogenic amylase and glucoamylase production, respectively.

• Korean Journal of Microbiology
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• v.14 no.2
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• pp.47-56
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• 1976

Enzyme activities, such as glucoamylase dextrinogenic amylase, cellulase, acid protase and neutral protease, of Rhizopus isolated from various substrates collected throughout South Korea are measured, and their enzyme activities are surveyed from taxonomical, ecological and physiological viewpoint. Effect of carbon sources and phytohormones on the amylalse production of Rhizopus are also measured. Among the 735 strains of Phizopus isolated, strain number 587 exhibiting most prominent dextrinogenic amylase and netral protease activity is selected as the best strain, and the strain number 673, 108, 329, 165 and 728 are seleted for their predominant cellulase, acid protease, glucoamylase, dextrinogenic amylase and neutral protease activities, respectively. R.acidus and R.nigricans which exhibited relatively higher callulalse activity, showed lower activities for both amylase. R.tritici exhibited higher protease activity. The relations between activities and various substrates of wild strains are not outstnading difference, although the strains isolated from inland region exhibited more or less higher amylase and cellulase activities, than those of coast region, generally. Lactose and dextrin are most effective carbon sources for glucoamylase and dextrinogenic amylase production of the Rhizopus niveus, respectively. Although all phytohormones tested are effective for production of amylase by the Rhizopus strains, except nicotinamide for glucoamylase production, biotin and ascorbate are most effective for dextrinogenic amylase and glucoamylase production, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.1
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• pp.18-22
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• 2011

Study on extraction and color characteristics of mulberry fruit pigment(C3G; cyanidin-3-glucoside) was performed to increase utilization as new source of natural food colorant. C3G was extracted with 0.1 % citric acid-70% EtOH. Then it was evaporated with large scale evaporation system. After adding dextrin to C3G concentration materials, we made pigment powder with freezing dryer.

• Mycobiology
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• v.31 no.4
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• pp.214-220
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• 2003

The fruiting body of Paecilomyces fumosoroseus was collected at Mt. Mani, Ganghwa Island, Korea in September, 2001. This study was carried out to obtain the basic informations for the mycelial growth and fruiting body production of P. fumosoroseus in artificial media. The optimal conditions for the mycelial growth were obtained at $25^{\circ}C$ and in the range of pH $6{\sim}9$, respectively. P. fumosoroseus showed the favorable growth on Hamada medium. The carbon and nitrogen source favorable for mycelial growth were dextrin and histidine, respectively. Optimum C/N ratio suitable for optimal growth of P. fumosoroseus was observed on the culture media adjusted to the ratio of 40:1. The mycelial growth of P. fumosoroseus was optimal on corn meal agar supplemented with 30% of silkworm pupae. The most favorable fruiting body formation of P. fumosoroseus was obtained in the medium containing unpolished rice supplemented with 20%(w/w) silk worm pupae at $25^{\circ}C$ under 100 lux.

• Mycobiology
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• v.36 no.1
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• pp.28-33
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• 2008

Ganoderma lucidum (Fr.) Karst (Polyporaceae), belonging to basidiomycota, is one of the most famous medicinal mushrooms. This study was carried out to investigate favorable mycelial growth conditions, such as pH, temperature, growth media, carbon sources and nitrogen sources of Korean strains in G. lucidum. The most suitable temperature for the mycelial growth was obtained at $30^{\circ}C$. In general, optimal temperature range for the mycelial growth was found at $25{\sim}30^{\circ}C$. This Mushroom has a broad pH range ($5{\sim}9$) for its mycelial growth and mostly favorable growth was found at pH 5. Generally, Hamada, Glucose peptone, YM, Mushroom complete and Lilly media were the most suitable for the mycelial growth of G. lucidum. Among 10 different carbon sources, dextrin, galactose and fructose were best but the rest of other carbon sources also facilitated the growth of mycelia. The most suitable nitrogen sources were ammonium acetate, glycine, arginine and calcium nitrate, but to a certain extent, all of the supplemented nitrogen sources also stimulated the mycelial growth.

• Journal of Microbiology
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• v.44 no.3
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• pp.276-283
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• 2006

The thermophilic fungus Thermoascus aurantiacus 179-5 produced large quantities of a glucosidase which preferentially hydrolyzed maltose over starch. Enzyme production was high in submerged fermentation, with a maximal activity of 30 U/ml after 336 h of fermentation. In solid-state fermentation, the activity of the enzyme was 22 U/ml at 144 h in medium containing wheat bran and 5.8 U/ml at 48 h when cassava pulp was used as the culture medium. The enzyme was specific for maltose, very slowly hydrolyzed starch, dextrins (2-7G) and the synthetic substrate (${\alpha}$-PNPG), and did not hydrolyze sucrose. These properties suggest that the enzyme is a type II ${\alpha}$-glucosidase. The optimum temperature of the enzyme was $70^{\circ}C$. In addition, the enzyme was highly thermostable (100% stability for 10 h at $60^{\circ}C$ and a half-life of 15 min at $80^{\circ}C$), and stable within a wide pH range.

• Journal of Applied Biological Chemistry
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• v.59 no.4
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• pp.289-298
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• 2016

FK506 hyper-yielding mutant, called the TCM8594 strain, was made from Streptomyces tsukubaensis NRRL 18488 by mutagenesis using N-methyl-N'-nitro-N-nitrosoguanidine, ultraviolet irradiation, and FK506 sequential resistance selection. FK506 production by the TCM8594 strain improved 45.1-fold ($505.4{\mu}g/mL$) compared to that of S. tsukubaensis NRRL 18488 ($11.2{\mu}g/mL$). Among the five substrates, wheat bran was selected as the best solid substrate to produce optimum quantities of FK506 ($382.7{\mu}g/g$ substrate) under solid-state fermentation, and the process parameters affecting FK506 production were optimized. Maximum FK506 yield ($897.4{\mu}g/g$ substrate) was achieved by optimizing process parameters, such as wheat bran with 5 % (w/w) dextrin and yeast extract as additional nutrients, 70 % (v/w) initial solid substrate moisture content, initial medium pH of 7.2, $30^{\circ}C$ incubation temperature, inoculum level that was 10 % (v/w) of the cell mass equivalent, and a 10 day incubation. The results showed an overall 234 % increase in FK506 production after optimizing the process parameters.

• Microbiology and Biotechnology Letters
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• v.21 no.1
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• pp.6-12
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• 1993

Among 294 Actinomycetes isolated from soil, a strain that had appeared to produce the highest level of chitinase selected for further studies. The selected strain was identified as a Streptomyces lydicus based on the data obtained from the morphological, biochemical and cultural experiments. The cultural conditions for the enzyme production were also examined, and the results obtained were as follows: the maximal enzyme production was attained when the cells were cultured at $30^{\circ}C$ for 6 days in the medium supplemented with 2% of colloidal chitin. The optimum initial pH of the medium was observed to be 8. It was also found that the most effective carbon and nitrogen sources were soluble starch and ammonium oxalate, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.1
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• pp.98-103
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• 1994

Some quality characteristics of tofu prepared with soyprotein isolate (SPI) were investigated to study the effects of various ratio of coagulants mixture and addition of oil, sucrose and dextrin. The tofu was prepared by addition of coagulants into the boiled SPI suspension and compression. The results showed that the mixed coagulants of CaCl $_2$-GDL(50 :50) and CaSO$_4$-GDL(25 :75) resulted the highest volume yield of 4.23g/g SPI among the various ratios of CaCl$_2$-CaSO$_4$, CaCl$_2$-GDL and CaSO$_4$-GDL. The water holding capacity(WHC) expressed as the area of water absorbed on filter paper was relatively high for those tofu coagulation with CaCl$_2$-GDL(75 : 25) and CaSO$_4$ -GDL(75 : 25). Addition of sucrose or oil-sucrose (1 : 1) decreased the yield wihle WHC was improved. Their addition also caused less hard and cohesive tofu which was coagulated by CaCl$_2$-GDL(75 : 25) and CaSO$_4$-GDL(75 : 25).

• Mycobiology
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• v.37 no.2
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• pp.94-102
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• 2009

Ganoderma applanatum is one of the most popular medicinal mushrooms due to the various biologically active components it produces. This study was conducted to obtain basic information regarding the mycelial culture conditions of Ganoderma applanatum. Based on the colony diameter and mycelial density, PDA, YMA and MCM media were suitable for the mycelial growth of the mushroom. The optimum temperature for mycelial growth was found to be $25{\sim}30^{\circ}C$. The optimum carbon and nitrogen sources were mannose and dextrin, respectively, and the optimum C/N ratio was 2 to 10 when 2% glucose was used. Other minor components required for the optimal growth included thiamine-HCl and biotin as vitamins, succinic acid and lactic acid as organic acids, and $MgSO_4$ $7H_2C$, $KH_2PO_4$ and NaCl as mineral salts.