• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.304-310
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• 1995

A thermophilic bacterium producing the extracellular cellulase-free xylanase was isolated from soil and has been identified as Bacillus sp. The optimal growth temperature was 50$\circ$C and the optimal pH, 7.0. Under the optimal growth condition, maximal xylanase production was 2.2 units/ml in the flask culture. The enzyme production was induced by xylan and xylose, but was repressed by sucrose or trehalose. The partially purified xylanase was most active at 70$\circ$C. It was found that the enzyme was stable at 65$\circ$C for 10 hours with over 75% of the activity. The enzyme was most active at pH 7.0 and retained 90% of its maximum activity between pH 5.0 and pH 9.0 though Bacillus sp. was not grown on alkaline conditions (>pH 8.0). In addition, the activity of xylanase was over 60% at pH 10.0. At the ambient temperature, the enzyme was stable over a pH range of 5.0 to 9.0 for 10 h, indicating that the enzyme is thermostable and alkalotolerant. The activity of xylanase was completely inhibited by metal ions including Hg$^{2+}$ and Fe$^{2+}$, while EDTA, phenylmethylsulfonyl fluoride (PMSF), $\beta$-mercaptoethanol and SDS didn't affect its activity. The enzyme was also identified to exert no activity on carboxymethylcellulose, laminarin, galactomannan, and soluble starch.

• Microbiology and Biotechnology Letters
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• v.27 no.2
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• pp.129-135
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• 1999

EH-1 was highest at 9 days of incubation. This regrowth and enzymatic activity of Haloarcular sp. EH-1 was highest at 9 days of incubation. This amylase was purified by acetone fractionation, DEAG-Cellulose column chromatography, 1st Sephadex G-75 gel filtration, CM-Cellulose column chromatography and 2nd Sephadex G-75 gel filtration. The amylase was purified about 98.64 fold with a yield of 11.75%. The molecular weight of amylase was estimated to be about 43,000and 40,000 by gel filtration and SDS-polyacrylamide gel electrophoresis, respectively, suggesting that the enzyme was a monomer. Amylase had an optimal temperature of 4$0^{\circ}C$, and an optimum pH of 7.0, and the thermal stability was observed the above 50% at 10$0^{\circ}C$ after 1 hour, and the stable range of pH was 6.0 to 8.0. The enzymatic activity was increased in the presence of 10 mM 2-mercaptoethanol, slightly by 10 mM SnCl2.2H2O.FeCl2.4H2O.CuCl2.2H2O.HgCl2.6H2O and SDS. End products from soluble starch were glucose, maltose and maltotriose, and Km value for soluble starch was 2.5mg/ml.

• Journal of Life Science
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• v.9 no.5
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• pp.510-517
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• 1999

For the treatment of Korean food-wastes, three mesophilic and one thermophilic bacteria were isolated from soil and fermented fertilizers. The thermophilic Streptomyces sp. strain WF021 produced two enzymes which were a protease and a lipase at 55$^{\circ}C$. The mesophilic Bacillus sp. strain WF024 produced four enzymes which were a protease, a lipase, a amylase and a cellulase when the strain was grown both at 3$0^{\circ}C$ and 55$^{\circ}C$. The Bacillus sp. PY123 had produced three enzymes which were a protease, a cellulase and a lipase at 3$0^{\circ}C$. The Bacillus sp. strain CM1 produced three enzymes which were a protease, a amylase, and a cellulase at 3$0^{\circ}C$. The bacteria were grown in media containing 6% NaCl at least and did not have antagonism each other. The four isolates treated much more food-wastes than referance strains did. In a flask without aeration, three reference strains treated 15.4% of food-wastes, while four isolates treated 23.7% of food-wastes. In a flask with aeration, food-wastes were treated 67.3% by four isolates, and 64.3% by three reference strains, but 53.9% without bacteria. However, food-wastes were treated about 78% in a 200$\ell$-reactor made by Siwon Co., while 65.8% in a 20$\ell$-reactor made by Sanyo Co.

• Mycobiology
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• v.34 no.1
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• pp.14-21
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• 2006

Crude protein (CP) content of mechanically ground rice straw into small particles by an electric grinder and reducing value (RV) and soluble protein (SP) in the culture filtrate were lower than that of the chopped straw into $5{\sim}6\;cm$ lengths when both ground and chopped straws were fermented with Aspergillus ochraceus, A. terreus or Trichoderma koningii, at steady conditions. The reduction rate of RV, SP and CP was 22.2, 2.4, 7.3%; 9.1, 4.9, 8.5% or 0.0, 0.0, 3.6% for the three fungi, respectively. Chemical pretreatment of straw by soaking in $NH_{4}OH$ for a day caused significant increase in CP of the fermented straw than the other alkali and acidic pretreatments. Gamma irradiation pretreatment of dry and wet straw with water, specially at higher doses, 100, 200 or 500 kGy, caused significant increase in RV and SP as CP in the fermented straw by any of these fungi. Chemical-physical combination pretreatment of rice straw reduced the applied dose of gamma irradiation required for increasing fermentable ability of fungi from 500 kGy to 10 kGy with approximately the same results. Significant increases in RV and SP of fermented straw generally occurred as the dose of gamma irradiation for pretreated straw, which combined with $NH_{4}OH$, gradually rose. Whereas, the increase percentage in CP of fermented straw that was pretreated by $NH_{4}OH-10\;kGy$ was 12.4%, 15.4% or 8.6% for A. ochraceus, A. terreus or T. koningii, respectively.

• Journal of Microbiology and Biotechnology
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• v.5 no.1
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• pp.18-21
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• 1995

Endoglucanase gene of Pseudomonas sp. LBC505 was previously cloned in pUCl9 to yield plasmid pLC1. overproduction of endoglucanase was attempted by following ways. First, the endoglucanase gene of Pseudomonas sp. LBC505 cloned in pUCl9(pLC1) was tandemly inserted, step by step, into a expression vector pKK223-3 in a directly repeated form to enhance productivity of endoglucanase. Escherichia coli containing pKCC30 among the resulting plasm ids showed the higher yield of the endoglucanase. Ecoli harboring pKCC30 which had three inserted endoglucanase genes expressed about 12.3 times as much CMCase activity as Ecoli harboring pLCl. Second, the endoglucanase gene was subcloned into Bacillus subtilis expression vector pgnt41 for both overproduction and extracellular secretion of the endoglucanase. A resulting plasmid pgntc15 in Bacillus subtilis expressed 4.3-fold higher levels of CMCase activity than that of E.coli harboring pLCl and the endoglucanase produced was entirely secreted into the culture medium.

• Korean journal of applied entomology
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• v.29 no.1
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• pp.6-13
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• 1990

The banana insect pest species and their damages were surveyed from 9 vinyl hoses of Cheju Island on August in 18. A total of 5 pest species wre found ; banana root weevil (BRW) Cosmopolites sordidus Germar (Curculionidae) a wireworm Melonotus sp. (Elateridae), a spider mite teranychid sp. (Tetranychidae), mulberry mealybud Pseudococcus comstocki (Kuwana)(Pseudococcidae), and common cutworm Spodoptera litura (Fabricius)(Noctuidae). Among them, the BRW which attacked the rhizome of banana plant was newly recorded from Korea. It is assumed that the weevil would be introduced from Japan, Philippine or SriLan-Ka wiht the banana seedlings imported during early 1980's.

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.450-455
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• 1991

A protease hyperproducer, ampicillin resistant mutant, Serratia sp. SMNT-1 was selected from Serratia marcescens ATCC 21074 by mutagenesis. The protease productivity of this strain was about 11 times as much as that of the parental strain. The enzyme showed maximal activity at pH 9.0 and $40^{\circ}C$ and was stable over the pH range from 6.0 to 10.0 at $4^{\circ}C$, whereas it was unstable at $37^{\circ}C$ in alkaline condition. the enzyme was inactivated by heating at $60^{\circ}C$ for 10 min. The enzyme was inactivated by EDTA and reactivated by $Zn^{2+}, Co^{2+},\; and \; Mn^{2+}$, but the proteoiytic activity of the enzyme was not affected by DFP. From the above results, the protease produced by Serratia sp. SMNT-1 was classified as a metalloprotese.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.6
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• pp.1828-1833
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• 2016

The purpose of this research was to investigate the bacterial flora of healthy olive flounder larvae (Paralichthys olivaceus) and live feeds (Rotifer spp. and Artemia spp.). The total bacteria counts were $9.2{\times}10^7$ and $1.2{\times}10^{10}cfu/g$ and Vibrio sp.(82.8%) was dominant in rotifers. The total bacteria counts were $3.8{\times}10^6$ and $9.2{\times}10^6cfu/g$ and Vibrio sp.(73.3%) was dominant in artemia. In olive flounder larvae, the total bacteria counts were $1.4{\times}10^6{\sim}8.3{\times}10^7cfu/g$ and V. harveyi (38.5%) was dominant. It might be potential marker of disease outbreak in olive flounder larvae.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.158-160
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• 2018

Streptomyces sp. P3 was isolated from potato scab diseased tubers in Pyeongchang, Gangwon-do, Republic of Korea in 2017. Here, we report the draft genome sequences of P3 with 9,851,971 bp size (71.2% GC content) of the chromosome. The genome comprises 8,548 CDS, 18 rRNA and 66 tRNA genes. Although strain P3 did not show pathogenicity both potato tuber assay and radish seedling assay, it possesses tomatinase (tomA) gene among conserved pathogenicity-related genes in well characterized pathogenic Streptomyces. Thus, the genome sequences determined in this study will be useful to understand for pathogenic evolution in Streptomyces species, which already adapted to potato scab pathogens.

• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1780-1787
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• 2014

Arterial oxygen saturation ($SpO_2$) monitoring for newborns requires special attention in neonatal intensive care units (NICUs). Newborns have very low photo-plethysmogram (PPG) amplitudes and their body movements are difficult to contain. Hardware design and its associated signal processing algorithms should be robust enough so that faulty measurements can be avoided. In this study, improved designs were implemented to deal with low perfusion, motion artifact, and the influence of ambient light. Dynamic range was increased by using different LED intensities and a feedback system. To minimize the effects of motion artifact and to discard other unqualified data, four additional algorithms were used, which were based on dual-trace detection, continuity of DC level, morphology of PPG, and simultaneity check of $SpO_2$. Our $SpO_2$ system was tested with newborns with normal respiration in the NICU. Our system provided fast, real-time responses and 100% artifact detection was accomplished under 84% of $SpO_2$.