• Journal of Life Science
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• v.26 no.2
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• pp.198-203
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• 2016

This study aimed to isolate a novel agarase-producing marine bacterium and characterize its agarase, as agarases are known to produce biofunctional agarooligosaccharides or neo-agarooligosaccharides. A novel agar-degrading bacterium, SH-2, was isolated from the seawater of Namhae in Gyeongnam Province, Korea, and cultured in Marine agar 2216 medium. The 16S rRNA gene sequence represented 99% identity with that of the members of the Marinomonas genus; hence, the isolated bacterium was named Marinomonas sp. SH-2. The crude agarase was prepared from a culture medium of Marinomonas. sp SH-2, and exhibited maximum agarase activity at 170.2 units/l. The optimum conditions were pH 6.0 and 30℃ in 20 mM Tris-HCl buffer. The agarase activity of the bacterium was highly elevated from 20℃(42% relative activity) to 30℃(100%), and 82% activity was shown at 40℃. Its relative activities were less than 40% at over 40℃ after a 0.5 hr exposure. Relative activity was 100% at pH 6.0, while it was 72% and 48% at pH 5.0 and pH 7.0, respectively. The enzyme from Marinomonas sp. SH-2 degraded agarose to neoagarohexaose and neoagarotetraose, indicating that the enzyme is β-agarase. Thus, Marinomonas sp. SH-2 and its enzyme could be practical for applications in food, cosmetic, and medical research.

• The Korean Journal of Nuclear Medicine
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• v.33 no.4
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• pp.430-438
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• 1999

Purpose: We evaluated a rapid preparation procedures for the labeling and quality control of $^{99m}Tc$-ECD, $MAG_3$, and MIBI using microwave heating and Sep-Pak cartridges. Materials and Methods: $^{99m}Tc$ labeling of ECD, $MAG_3$, and MIBI kit preparation was performed according to the package inserts with microwave heating modification. Heating time was 10-15 sec, and heating was performed with 3 mm plastic bottle with screw cap to prevent radiation contamination. Labeling efficiency was obtained with $C_{18}$ or Alumina N Sep-Pak cartridges. Results: The radiochemical purity of $93{\sim}96%$ for $^{99m}Tc$-ECD and $95{\sim}99%$ for $^{99m}Tc$-MIBI was obtained using Alumina N Sep-Pak cartridge. The optimum irradiation time of microwave method for 3 ml $^{99m}Tc$-labeled radiopharmaceutical solution was 10 sec for $^{99m}Tc$-ECD and $^{99m}Tc$-MIBI, and 15 sec for $^{99m}Tc-MAG_3$. The results of quality control data with Sep-Pak cartridges were well correlated with TLC method. The total preparation time of these radiopharmcaeuticals was $5{\sim}6min$ including quality control procedure. Conclusion: This study demonstrates that radiopharmaceuticals preparation by microwave heating and quality control by Sep-Pak cartridges can be efficiently utilized as an alternative to the recommended method by manufacturer's manual.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.109-113
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• 2006

Antioxidant compound(s) were identified from the ethanol extract of wild grape (Vitis coignetiea) seed. Organic solvent fractions of n-hexane, chloroform, ethyl acetate and butanol were obtained from the ethanol extract of wild grape seed, among which ethyl acetate fraction showed the strongest reducing power. Ethyl acetate fraction was further purified through ODS column chromatography and HPLC, and isolated antioxidative active compound was identified through $^1H-NMR$ as (+)-catechin (52.7 g/100 g). (+)-Catechin and ethyl acetate fraction both showed approximately 80% scavenging effect. These results indicated (+)-catechin in the ethyl acetate fraction synergetically interacts with unknown antioxidative compound(s).

• Current Research on Agriculture and Life Sciences
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• v.14
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• pp.111-122
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• 1996

S. chibaensis J-59 produced an extracellular xylanase in a CSL medium composed of 1.5% com steep liquor, 0.1% $MgSO_4{\cdot}7H_2O$, 0.012% $CoCl_2{\cdot}6H_2O$, and 0.15% glucose containing xylan. but it did not produce in the culture medium containing xylose. The production of enzyme reached to a maximum level (0.83 uints/ml) when bacteria were cultured in 2.5 l jar fermentor for 48hrs at $30^{\circ}C$ and pH 7.0. Furthermore, S. chibaensis J-59 produced an intracellular glucose isomerase in a medium containing xylan and/or xylose. Xylanase was purified 29-fold over the culture supernatants of S. chibaensis J-59 by ammonium sulfate fractionation, chromatography on DEAE-Sephadex A-50, and gel filtration on Sephadex G-200. The purified enzyme is a monomeric enzyme with a native molecular mass of 25 kDa and a subunit molecular mass of 25 kDa. The purified enzyme requires $Mg^{2+}$ for activity, $Ca^{2+}$, $Co^{2+}$ is not an inhibitor but inhibit by $Fe^{3+}$, $Hg^{2+}$, and $Cu^{2+}$, sodium dodecyl sulfate, N-bromosuccinide. Pattern of hydrolysis demonstrated that the xylanase was an endo-splitting enzyme able to break down birchwood xylan at random giving xylobiose, xylotriose and xylotetrose as the main end products.

• Korean Journal of Food Science and Technology
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• v.10 no.3
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• pp.361-365
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• 1978

Physico-chemical characteristics of crude oil extracted from Korean Hazel nut were determined and its proximate composition was also analyzed. The proximate composition of Hazel nut was shown to be moisture 4.0%, crude protein 15.5%, crude fat 64%, nitrogen free extractive 11.7%, crude fiber 2.0% and crude ash 2.5%. The content of crude fat in Corylus sieboldiana was about 3% higher than in Corylus mandshurica.. Physico-chemical characteristics of crude oil found were: specific gravity, $0.916(15/15^{\circ}C)$; refractive index, $1.468(15^{\circ}C)$; saponification value, 184; iodine value, 94.5: acid value, 0.2; and unsaponifiable content, 0.25%. The lipid fractions in the crude oil obtained by silicic acid column chromatography were found to be composed of about 97% neutral lipids and about 3% compound lipids. Among the neutral lipids by TLC, triglycerides were 98% as the major components, free fatty acids and free strols were 0.5% and 1.3%, respectively. Esterified sterols were not found. The predominant fatty acids were oleic $(76{\sim}80%)$, linoleic (15%) and palmitic (5.0%), and the P/S ratio was $1.8{\sim}2.8$.

• 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.

• Journal of the Korean Wood Science and Technology
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• v.41 no.6
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• pp.566-575
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• 2013

The fruits of Taxus cuspidata were collected, divided into seeds and fruits, and extracted with 95% EtOH. The extracts were evaporated under the reduced vacuum pressure, concentrated, then successively fractionated with a series of n-hexane, dichloromethane, ethyl acetate and water on a separatory funnel to get some freeze dried samples. A portion of the EtOAc (arils:1.65 g, seeds:1.04 g) and $H_2O$ (arils:7 g, seeds:10 g) soluble samples were chromatographed on a Sephadex column using MeOH-$H_2O$ (1:1, 1:3, 1:5, v/v), EtOH-hexane (3:1, v/v) mixture and 100% $H_2O$ as eluting solvents to isolate pure compounds from the fractions. The isolates were developed by cellulose TLC using t-BuOH-HOAc-$H_2O$ (TBA; 3:1:1, v/v/v) and 6% aqueous HOAc. Visualization was done under ultraviolet light and by spraying the vanillin-HCl-EtOH reagent (4.8:12:480, v/v/v). followed by heating. The structures of the isolates were characterized by $^1H$- and $^{13}C$-NMR, DEPT, 2D-NMR, LC/MS and EI-MS spectra. In addition to the NMR and MS spectra, acid hydrolysis and permethylation were used to determine the correct structure of the isolated sugar compound. Their structures were elucidated as (+)-catechin (1), (-)-epicatechin (2), (+)-gallocatechin (3), (-)-epigallocatechin (4) and ${\beta}$-D-fructofuranose-($2{\rightarrow}4$)-O-${\beta}$-D-glucopyranose($1{\rightarrow}4$)-O-${\alpha}$-D-glucopyranose ($1{\rightarrow}2$)-O-${\beta}$-D-fructofuranose (5) on the basis of the above experimental evidences.

• Journal of Mushroom
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• v.19 no.3
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• pp.140-149
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• 2021

Mushroom-derived polysaccharides, which are the primary bioactive constituents, are beneficial for human health. Polysaccharides have immuno-modulation, antitumor, and antioxidant properties. Additionally, they have antiviral properties and protect against chronic radiation stress. In this study, high yield water-soluble polysaccharides were obtained from Pleurotus djamor var. roseus basidiocarps. The crude polysaccharide (CP) was extracted sequentially by hot water and ethanol precipitation. The yield of the brown CPs was 5.6% dw. Diethylaminoethyl cellulose and Sepharose-6B column chromatography of CPs generated several fractions. Total glucan content was determined in all the fractions. The F1 fraction displayed the highest sugar content and was considered as a purified polysaccharide (PP). The total glucan and β-glucan content in the four fractions ranged between 76.85-2.95% and 75.08-1.46%, respectively. The yield of the PPs was 300 mg, and it was obtained as a white powder. The PPs were characterized by Fourier-transform infrared spectroscopy (FTIR) and thin-layer chromatography. The FTIR spectral details confirmed the presence of a xylopentose polysaccharide. The antioxidant activity of the PPs was evaluated using in vitro 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay and superoxide radical scavenging assay. The PPs showed strong DPPH free radical and superoxide anion radical scavenging activities in a dose-dependent manner. Purified PPs free of phenolics, protein, and carbohydrates were mainly responsible for the radical scavenging activity. The data suggest the potential of PPs as natural antioxidants.

• Food Engineering Progress
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• v.15 no.2
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• pp.175-181
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• 2011

By using supercritical carbon dioxide fluid, an attempt was made to extract surface-active substances from defatted rice bran. Extraction was carried out according to D-optimal design and results were analyzed by response surface methodology to establish optimum condition. It was found that pressure, temperature and co-solvent (ethanol) influenced in a different extent on the extraction efficiency (i.e., yield and interfacial tension) of surface-active substances. Among them, co-solvent was found to be a major influencing factor, where maximum yield (2.62%) was observed at the highest content (250 g). In addition, it also affected most on the interfacial tension at the oil-water interface but in this case the lowest interfacial tension value (9.51 mN/m) was found when added lowest (50 g). In conclusion, it was estimated that the optimum extraction condition was to be pressure 350bar, temperature $62^{\circ}C$ and co-solvent content 50 g in this study, where extraction yield was 0.69% and interfacial tension to be 10.1 mN/m.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.572-580
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• 2018

Biologically active substances including gamma-aminobutryric acid (GABA) were added into whey by co fermentation using Bacillus subtilis HA and Lactobacillus plantarum EJ2014. The first fermentation using B. subtilis HA with 5% monosodium glutamate (MSG) and 2% glucose enhanced the production of poly-${\gamma}$-glutamic acid (PGA), resulting in higher consistency of $4.09Pas^n$ as well as whey protein peptides. After the second fermentation using L. plantarum EJ2014, the remaining MSG (3.40%) as a precursor was completely converted to 2.21% GABA. Furthermore, the lactose content in whey decreased from 6.73 to 3.68% after co-fermentation, and the tyrosine content increased from 20.47 to 38.24%. Peptides derived of whey proteins were confirmed by SDS-PAGE. Viable cell counts of B. subtilis and L. plantarum were 5.83 log CFU/mL and 9.20 log CFU/mL, respectively. Thus, co-fermentation of whey could produce the novel food ingredient fortified with biologically active compounds including GABA, ${\gamma}$-PGA, peptides, and probiotics.