• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.450-455
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• 1998

Aspergillus oryzae M-2-3 strain (argB$\^$-/) was transformed with pTAalp plasmid which was constructed for expression of the alkaline pretense gene, alpA, and 16 transformants were selected on arginine minus medium. When these transformants were tested for productivity of alkaline proteases using agar plate containing skim milk, the halo was observed around each colony of transformants, but not observed around the host strain in this condition. Southern analysis showed that the pTAalp plasmid having alpA gene was integrated into the chromosome of the host strain. The highest level of alkaline protease production was obtained in the culture filtrate of the transformant No. 14, which was estimated to 80-90% of total secreted proteins, and the enzyme activity was 64-450 times higher than those of host strain and industrial strain. Total nitrogen content and the digestion rate in soybean Koji extracts were also increased to 1.5 times in Aspergillus oryzae transformant No. 14.

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.524-534
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• 2017

The development and utilization of crop straw biogas resources can effectively alleviate the shortage of energy, environmental pollution, and other issues. This study performed a continuous batch test at $35^{\circ}C$ to assess the methane production potential and volatile organic acid contents using the modified Gompertz equation. Illumina MiSeq platform sequencing, which is a sequencing method based on sequencing-by-synthesis, was used to compare the archaeal community diversity, and denaturing gradient gel electrophoresis (DGGE) was used to analyze the bacterial community diversity in rice straw, dry maize straw, silage maize straw, and tobacco straw. The results showed that cumulative gas production values for silage maize straw, rice straw, dry maize straw, and tobacco straw were 4,870, 4,032.5, 3,907.5, and $3,628.3ml/g{\cdot}VS$, respectively, after 24 days. Maximum daily gas production values of silage maize straw and rice straw were 1,025 and $904.17ml/g{\cdot}VS$, respectively, followed by tobacco straw and dry maize straw. The methane content of all four kinds of straws was > 60%, particularly that of silage maize straw, which peaked at 67.3%. Biogas production from the four kinds of straw was in the order silage maize straw > rice straw > dry maize straw > tobacco straw, and the values were 1,166.7, 1,048.4, 890, and $637.4ml/g{\cdot}VS$, respectively. The microbial community analysis showed that metabolism was mainly carried out by acetate-utilizing methanogens, and that Methanosarcina was the dominant archaeal genus in the four kinds of straw, and the DGGE bands belonged to the phyla Firmicutes, Bacteroidetes, and Chloroflexi. Silage maize is useful for biogas production because it contains four kinds of straw.

• Journal of Pharmaceutical Investigation
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• v.35 no.6
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• pp.453-460
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• 2005

4-Aminopyridine (AP) is a potassium channel blocker used in the treatment of neurological disorders such as multiple sclerosis and Alzheimer disease. AP‘s window of therapeutic effect appears to correlate with its plasma halflife (3.5 hours). It demonstrates pH-dependent solubility because of a weakly basic drug. In addition, the resulting release from conventional matrix tablets decreases with increasing pH-milieu of the gastrointestinal tract. The aim of this study is to design sustained release matrix tablet containing AP, overcoming this problem. $Eudragit^{\circledR}$ L 100 (EuL) and sodium alginate were used in an effort to achieve pH independent drug release. The effect of sodium alginate and EuL on drug release from matrix tablet was investigated. The drug release behavior from the different tablets was analyzed by $t_{20%},\;t_{40%},\;t_{60%}$, The exponential diffusion coefficient n, kinetic constant K were calculated according to the Korsmeyer-Peppas equation. The drug release from matrix tablets prepared with sodium alginate was decreased with increasing the content of sodium alginate in pH 7.4 while there is no significant difference in pH 1.2. The exponent n values were determined to be approximately 0.5 and 0.8 respectively, in both pH 1.2 and 7.4. These values indicate diffusion-based anomalous mechanism and erosion-based anomalous mechanism, respectively. The drug release from sodium alginate matrix tablets prepared with solid dispersion of EuL containing drug showed a slow drug release in an acidic medium and a more fast drug release in phosphate medium, compared with sodium alginate matrix tablets prepared with physical mixture. These results may be attributed to the gel forming ability of sodium alginate and pH dependent solubility of EuL. Therefore, sustained-release AP matrix tablets using sodium alginate and EuL were successfully prepared.

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.32-38
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• 2006

A series of organic-inorganic hybrids, PCL/EP/$SiO_2$, involving epoxy resin and triethoxysilane-terminated polycaprolactone elastomer (PCL-TESi) were prepared via polymerization of diglycidyl ether of bisphenol A (DGEBA) with amine curing agent KB-2 and sol-gel process of PCL-TESi. The curing reactions were started from the initially homogeneous mixture of DGEBA, KB-2 and the PCL-TESi. The organicinorganic hybrids containing up to 4.95% (wt) of $SiO_2$ were obtained and characterized by FT-IR, transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). It was experimentally shown that the swelling property in toluene, morphologies and thermal properties of the resulting hybrids were quite dependent on the contents of $SiO_2$. The crosslink network density decreases with increasing of the PCL-TESi. And in TEM, the phase separated morphology of these hybrids was found, which resulted from the coagulation of Si-O-Si networks resulting from $-Si(OC_2H_5)_3$ of PCL-TESi self-curing by hydrolytic silanol condensation, with the advancement of the curing reaction in the modified epoxy resin systems. Meanwhile, the change of the $SiO_2$ content made the morphologies changed from aggregated particles of Si-O-Si in the hybrid to nanocluster of interconnected Si-O-Si particles, then to aggregated Si-O-Si dispersing in the continuous cured epoxy phase again, and last to co-continuous interpenetrating network. The glass transition behavior of the hybrid material was cooperative motion of large chain segments, which were hindered by the inorganic Si-O-Si network. And in TG analysis, the characteristic temperature at 5% of weight loss was evidently increased from $120.5^{\circ}C$ of pure cured epoxy to $277.6^{\circ}C$ of 3.84% (wt) of $SiO_2$ modified epoxy due to the existence of Si-O-Si when PCL-TESi was added in the hybrid.

• Journal of the Korean Ceramic Society
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• v.36 no.2
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• pp.159-166
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• 1999

The physical properties and microstructural changes with heat-treatment of opacified silica aerogels doped by TiO2 were investigated. Monolithic SiO2-TiO2 aerogels were prepared by supercritical drying (25$0^{\circ}C$, 1250 psig) of wet gel obtained by adding titanium isopropoxide to prehydrolyzed TEOS-isopropanol solutions. The density and the porosity of SiO2-10 mol% TiO2 aerogels were 0.23 g/㎤ and 90%, respectively. During supercritical drying, the linear shrinkage of aerogels increased with increase in the titanium content an TiO2 was transformed to the anatase phase as well as particls agglomerates led to TiO2 clusters of 100~800 nm dispersed homogeneoulsy in the silica matrix. The IR transmittance of opacified silica aerogels was very low in the region of wavelengths below 8 ${\mu}{\textrm}{m}$ compared with pure silica aerogels and SiO2-TiO2 aerogels showed the high thermal stability of microstructures up to $600^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.2
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• pp.133-142
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• 1990

This study was attempted to compare the nutritive value of leaf with stem of the water cress Oenanthe stolonifera DC. in order to improve the eating habits and as a part of studying on the effective curing nutrients for the damaged liver. The contents of moisture crude proteinon the effective curing nutrients for the damaged liver. The contents of moisture crude protein crude fat and crude ash were 90.40% 2.85%, 0.42% and 0.74% in leaf while the contents of moisture crude protein crude fat and crude ash were 95.15% 0.77% 0.09%, and 0.64% of moisture crude protein crude fat and crude ash were 95.15% 0.77% 0.09% and 0.64% in stem respectively. The quantitative fractionation of proteini of both leaf and stem ranked albumin the highest content followed globulin prolamin and glutelin in order. It has been sh-own by SDS-polyacrylamide gel electrophoresis that water extractable protein of leaf 11 bands but those of stem were not detected. The scope of molecular weight for the main protein of water extractable protein of leaf was between 34.700 and 45,000. The amounts of extractive-nitrogen from leaf and stem of the water cress were 241.02mg% and 271.67mg% respec-tively. The amounts of free amino acid-nitrogen from the leaf and stem were 89.02mg% and 32.02mg% respectively. In free amino acid-nitrogen from the leaf and stem were 89.02mg% and 32.02mg% respectively. In free amino acid composition of both leaf and stem the major components were aspartic acid and glutamic acid. In total amino acid composition of water cress leaf aspartic and glutamic acid were the major components. Whereas alanine and thr-eonine were the major components in stem The assessment of water cress leaf and stem with chemical score. EAAl Rl showed that the values of stem were lower tendancy than those of leaf. Limiting amino acid of leaf was tryptophan while that of stem was lysine.

• Genomics & Informatics
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• v.10 no.4
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• pp.249-255
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• 2012

In this study, fosmid cloning strategies were used to assess the microbial populations in water from the International Space Station (ISS) drinking water system (henceforth referred to as Prebiocide and Tank A water samples). The goals of this study were: to compare the sensitivity of the fosmid cloning strategy with that of traditional culture-based and 16S rRNA-based approaches and to detect the widest possible spectrum of microbial populations during the water purification process. Initially, microbes could not be cultivated, and conventional PCR failed to amplify 16S rDNA fragments from these low biomass samples. Therefore, randomly primed rolling-circle amplification was used to amplify any DNA that might be present in the samples, followed by size selection by using pulsed-field gel electrophoresis. The amplified high-molecular- weight DNA from both samples was cloned into fosmid vectors. Several hundred clones were randomly selected for sequencing, followed by Blastn/Blastx searches. Sequences encoding specific genes from Burkholderia, a species abundant in the soil and groundwater, were found in both samples. Bradyrhizobium and Mesorhizobium, which belong to rhizobia, a large community of nitrogen fixers often found in association with plant roots, were present in the Prebiocide samples. Ralstonia, which is prevalent in soils with a high heavy metal content, was detected in the Tank A samples. The detection of many unidentified sequences suggests the presence of potentially novel microbial fingerprints. The bacterial diversity detected in this pilot study using a fosmid vector approach was higher than that detected by conventional 16S rRNA gene sequencing.

• BMB Reports
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• v.38 no.5
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• pp.526-532
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• 2005

A lectin with in-vitro anticancer activity against established human cancer cell lines has been purified by affinity chromatography on asialofetuin-linked amino activated silica beads from the tubers of Arisaema tortuosum, popularly known as Himalayan Cobra lily, a monocot plant from the family Araceae. The bound Arisaema tortuosum lectin (ATL) was eluted with glycine-HCl buffer, pH 2.5. ATL was effectively inhibited by asialofetuin, a complex desialylated serum glycoprotein as well as by N-acetyl-D-lactosamine, a disaccharide. It gave a single band corresponding to a subunit molecular weight of 13.5 kDa in SDS-PAGE, pH 8.8 both under reducing and non reducing conditions. When subjected to gel-filtration on Biogel P-200, it was found to have a molecular weight of 54 kDa, suggesting a homotetramer structure, in which individual polypeptides are not bound to each other with disulfide bonds. ATL is a glycoprotein with 0.9% carbohydrate content, stable up to $55^{\circ}C$ and at pH 2 to 10. The lectin had no requirement for divalent metal ions i.e. $Ca^{2+}$ and $Mn^{2+}$ for its activity. However, as reported for other monocot lectins, ATL gave multiple bands in isoelectric focusing and Native PAGE, pH 8.3. The lectin was found to inhibit in vitro proliferation of human cancer cell lines HT29, SiHa and OVCAR-5.

• BMB Reports
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• v.36 no.2
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• pp.230-236
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• 2003

Hot water-soluble crude polysaccharide (HCAP-0) that was obtained from the fruits of Capsicum annuum showed potent anti-complementary activity. The activity was unchanged by pronase digestion, but decreased by periodate oxidation. The HCAP-0 was fractionated by DEAE ion-exchange chromatography to give two major fractions, HCAP-II and III. These two fractions were finally purified by gel filtration to give HCAP-IIa, HCAP-IIIa1, and IIIa2 fractions that had high anti-complementary activities. The HCAP-IIIa1 and IIIa2 consisted of homogeneous polysaccharides. The anti-complementary activities were unaffected by treatment with polymyxin B, indicating that the modes of complement activation were not due to preexisting lipopolysaccharide. The molecular weight and sugar content of HCAP-IIIa2 had potent anti-complementary activity. The highest yields were 55 kDa and 75.9%, and the molar ratio of galactose (Ara:Gal, 1.0:4.6) was higher than other sugars. The crossed immuno-electrophoresis showed that both classical and alternative pathways were activated by HCAP-IIIa2.

• Food Science of Animal Resources
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• v.34 no.4
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• pp.543-551
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• 2014

The aim of this study was to evaluate the effect of proteolytic (Serratia liquefaciens, match %: 99.39) or lipolytic (Acinetobacter genomospecies 10, match %: 99.90) psychrotrophic bacteria (bacterial counts, analysis of free fatty acids (FFA) and analysis of free amino acids) on the microbial and chemical properties (yogurt composition), and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of yogurt during storage. Yogurts were prepared with raw milk preinoculated with each psychrotrophic bacteria. The total solid, fat, and protein content were not affected by preinoculation, but the pH of yogurt preinoculated with psychrotrophic bacteria was higher than in control. There was a dramatic increase in short chain free fatty acids among FFA in yogurt with Acinetobacter genomospecies 10. For 14 d of cold storage condition, SCFFA was 25.3 mg/kg to 34.4 mg/kg (1.36 times increased), MCFFA was 20.4 mg/kg to 25.7 mg/kg (1.26 times increased), and LCFFA was 240.2 mg/kg to 322.8 mg/kg (1.34 times increased). Serratia liquefaciens (match %: 99.39) in yogurt caused a greater accumulation of free amino acids (FAA), especially bitter peptides such as leucine, valine, arginine, and tyrosine, but SDS-PAGE showed that the inoculation of Serratia liquefaciens did not affect the degree of casein degradation during storage. Taken together, the excessive peptides and FFA in yogurt generated from psychrotrophic bacteria could develop off-flavors that degrade the quality of commercial yogurt products.