• Food Science and Biotechnology
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• v.18 no.2
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• pp.519-525
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• 2009

A bacterial strain (Strain N-08) capable of extracellularly producing high level of non-reducing oligosaccharide (NR-OS) isolated from soil. The strain was identified phylogenetically by 16S rDNA sequence analysis and found to be very close to Arthrobacter crystallopoietes. The high production of NR-OS was observed in the basal culture medium containing maltose as a sole carbon source. The NR-OS in culture supernatant was purified by glucoamylase treatment and Dowex-1 (OH.) ion exchange chromatography and its structure was characterized. This oligosaccharide consisted of only glucose. Methylation analysis indicated that this fraction was composed mainly of non-reducing terminal glucopyranoside. Matrixassisted laser-induced/ionization time-of-flight (MALDI-TOF) and electrospray ionization-mass spectrometry (ESI-MS)/MS analyses suggested that this oligosaccharide comprised non-reducing disaccharide unit with 1,1-glucosidic linkage. When this disaccharide was analyzed by $^1H$-NMR and $^{13}C$-NMR, it gave the same signals with $\alpha$-D-glucopyranosyl-(1,1)-$\alpha$-Dglucopyranoside. These results indicated that the NR-OS produced by A. crystallopoietes N-08 was ${\alpha}1$,${\alpha}1$-trehalose. This is the first report of the trehalose which can be produced directly from maltose by A. crystallopoietes N-08.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.572-575
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• 2007

The angiontensin converting enzyme (ACE) inhibitory peptides were separated from beef sarcoplasmic protein extract and their amino acid sequences were identified as GFHI, DFHINQ, FHG, and GLSDGEWQ. The 4 peptides were synthesized in a laboratory and the ACE inhibitory activities of pep tides was measured after 2 months of storage at $4^{\circ}C$ under different pH conditions (6.0, 6.5, 7.0, 7.5, and 8.0) and the exposure of different temperatures (70, 80, 90, and $100^{\circ}C$) for 20 min to evaluate industrial use. No significant difference was detected by pH and temperature abuse for 20 min during storage. When the synthetic peptides were digested by pepsin, trypsin, and chymotrypsin, the ACE inhibitory activity was not changed. These results indicated that the 4 synthetic peptides with ACE inhibitory activity were pH-stable, heat-stable, and resistant to proteinases in gastro-intestinal tracts. Therefore, those 4 peptides can be used as a source for functional food product with various applications.

• Food Science of Animal Resources
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• v.31 no.2
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• pp.176-182
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• 2011

The bacteriocin-producing lactic acid bacteria Enterococcus faecium DB1 was isolated from Korean traditional gajami sikhae. Culture conditions were optimized by response surface methodology (RSM) to maximize bacteriocin DB1 production. E. faecium DB1 displayed the highest bacteriocin activity when grown in modified MRS medium containing sucrose, rather than glucose, as a carbon source. The effects of temperature, initial pH, and sucrose concentration were tested to determine the optimum conditions for maximum bacteriocin production by E. faecium DB1. A central composite design was used to control the three variables in the experiment. RSM revealed that the optimum values for bacteriocin production were 27.66 g/L sucrose, temperature of $34.37^{\circ}C$, and an initial pH of 6.54. A 2.08-fold increase in bacteriocin production was obtained with sucrose-containing MRS medium compared to production in standard MRS medium.

• Journal of the Korean Home Economics Association
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• v.39 no.12
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• pp.51-63
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• 2001

With the development of information technology, more and more internet sites are available to consumers. Increasing on the interests of diet and health in modem society, there are numerous internet sites dealing with food, nutrition and health. Considering the importance and expected roles of internet sites in information dissemination in the future world, it is important to put more efforts to encourage internet sites with more accurate an useful information. Up to present, not much work has been done on quality analysis and evaluation of the internet information. This study aimed to develop a model to evaluate and rank the internet information according to its quality so that consumers can be guided toward correct information source. Three models were adapted from the literature for pilot study to develop a model suitable for evaluation of contents of sites related to food and nutrition information. From the pilot study, a evaluation model was developed with criteria more relevant to Korean internet site by expert panel. Evaluation criteria of the model is authority, accuracy, objectivity, coverage, and user-friendliness. For the objective and systematic evaluation, scores were assigned totaling maximum 100 point to each evaluation criteria factors. The model developed in this study could be used as one for other internet sites in area other than food and nutrition.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.644-649
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• 2007

In this study a purified protein was prepared from pork meat. The product consisted of 0.5% moisture, 3.0% ash, 5.5% ether extract and 88.7% crude protein. Also, a meat oligopeptide mixture was prepared from a pepsin digest of the protein preparation. The two preparations were colorless and odorless powders with low fat contents. The nutritive values of the pork meat protein and oligopeptide mixture were estimated by two methods, one using biological value(BV) and the other employing net protein utilization(NPU) by the nitrogen balance method. The meat oligopeptide mixture showed an excellent nutritive value by both methods. The true digestibilites of both the pork meat protein and the oligopeptide mixture were more than 98%. The above results indicate that the oligopeptide mixture is an excellent material as a dietary nitrogen source for many purposes.

• Korean Journal of Medicinal Crop Science
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• v.18 no.6
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• pp.373-378
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• 2010

In order to obtain basic data for utilization of the aerial parts of Cnidium officinale Makino (APCO), the antioxidant properties of the aerial parts and rhizomes of C. officinale were measured using DPPH and ABTS radicals, and nitrite scavenging assays. The ethyl acetate (EA) fraction prepared from the aerial parts of APCO showed the strongest antioxidant activities, and contained high level of total phenolic compounds (325.81 mgTE/g) and flavonoids (259.16 mgRE/g). The concentrations for 50% reductions ($RC_{50}$) values of the DPPH and ABTS radicals, and nitrite by the EA fraction of APCO were $11.27\;{\mu}g/m{\ell}$, $14.34\;{\mu}g/m{\ell}$, and $10.26\;{\mu}g/m{\ell}$, respectively. APCO exhibited approximately 3-9 times higher antioxidant activity than rhizomes of C. officinale. The antioxidant capacities of APCO were positively correlated with its total phenolic contents. Therefore, it was concluded that the aerial parts of C. officinale can be a useful and cost-effective source of natural antioxidant for food or cosmetics.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.81-81
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• 2018

The present study was investigated on in vitro anti-obesity effect of 4-hydroxybenzyl alcohol from Cudrania tricuspidata. We isolated various compounds from Cudrania tricuspidata. Among these compounds, anti-obesity effects of 4-hydroxybenzyl alcohol was examined by lipase activity assay, cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase type IV (PDE4) activity assay, and citrate synthase activity assay. 4-hydroxybenzyl alcohol and Cudrania tricuspidata extracts inhibited the enzymatic activities of lipase, PDE4, and citrate synthase. Lipase is known to mediate the hydrolysis of triacylglycerol in adipose tissue and cholesterol esters in other tissue or cells. Also, PDE4 hydrolyses cAMP, a crucial secondary messenger for in metabolic pathways including glucose and lipid metabolism, lipolysis, and thermogenic function. 4-hydroxybenzyl alcohol and Cudrania tricuspidata extracts induced the inhibitory effect against each enzymatic activity on several specific substrates as observed by detection at 405 or 412 nm. These findings might be attributable to the inhibition of adipogenesis, and partial prevention of obesity. In conclusion, these results show that 4-hydroxybenzyl alcohol and Cudrania tricuspidata may be a critical candidate as a natural anti-obesity source.

• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.414-419
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• 1987

Cultural conditions for the polysaccharide production by Pseudomonas elodea ATCC 31461, a thermogellable polysaccharide producer, were investigated. Optimum condition for polysaccharide production were: temperature; $30^{\circ}C$, pH; 6.5, glucose; 25 g/L. nitrogen source; peptone, C/N ratio; 5.0. Maximum production and yield at this condition were ca. 32 g/L and 128%, viscosity of 1% polysaccharide solution was 837 mPas at 35/sec.. Consistency index and flow behaviour index were 2570 mPas and 0.66

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.195-201
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• 2007

This study investigated the effects of various culture parameters (carbon sources, temperature, initial pH of culture, NaCl concentration, and light) on the growth and canthaxanthin production by Dietzia natronolimnaea HS-1. The results showed that the most effective carbon source for growth and canthaxantin production was glucose, and the best pH and temperature were 7 and $31^{\circ}C$, respectively. In addition, the biomass and canthaxanthin production increased in a medium without NaCl and in the presence of light. Under the optimized conditions, the maximum biomass, total carotenoid, and canthaxanthin production were $6.12{\pm}0.21g/l,\;4.51{\pm}0.20mg/l,\;and\;4.28{\pm}0.15mg/l$, respectively, in an Erlenmeyer flask system, yet increased to 7.25 g/l, 5.48 mg/l, and 5.29 mg/l, respectively, in a batch fermenter system.

• Preventive Nutrition and Food Science
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• v.17 no.2
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• pp.172-176
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• 2012

Doenjang is a traditional Korean fermented soybean product that provides a major source of protein. In this study, a total of 18 different home-made doenjang samples were examined for the presence of foodborne pathogens and the total aflatoxin levels. Using an enzyme-linked immunosorbent assay to assess microbial quality and potential public health risk, we showed that total coliform levels in the doenjang samples ranged from 0 to $4.43{\pm}2.32{\times}10^6\;CFU/g$, and the maximum limit of Bacillus cereus was $4.67{\pm}2.0{\times}10^5\;CFU/g$. However, other foodborne pathogens, such as Staphylococcus aureus, Escherichia coli O157:H7 and Salmonella spp., were not detected among the tested samples. One of the samples (S3) showed a maximum limit of $42.2{\pm}9.1\;{\mu}g/kg$ for aflatoxin levels, which was above the safety limit allowed by the Codex Alimentarius Commission (CAC) regulatory agency. Further research is necessary to determine whether and how doenjang safety can be improved via elimination/reduction of microbial contamination during fermentation and storage or using microbial starter cultures for its fermentation.