• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1188-1192
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• 2003

Chitinase producing bacteria, Arthrobacter nicotianae CH4 and A. nicotianae CH13, were isolated from small crabs by an enrichment culture using chitin as the sole carbon source. Crude chitinases from the two isolated strains, A. nicotianae CH4 and A. nicotianae CH13, were stable in the pH range of $3.0{\sim}9.0$ and in the temperature range of $20{\sim}60^{\circ}C$. The reducing sugar $(GlcNAc)_1$, or $(GlcNAc)_4$, corresponding to over 98% of the enzyme reaction products, was obtained. The production of functional $(GlcNAc)_1$ and $(GlcNAc)_4$ from A. nicotianae CH13 and A. nicotianae CH4, respectively, from the chitinases was useful. The chitinase system of A. nicotianae CH13 was supposed to be endo- and exo-chitinase, and N-acetylglucosaminidase.

• Journal of Ginseng Research
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• v.40 no.3
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• pp.237-244
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• 2016

Background: Ginsenoside Rg3 and arginine-fructose (Arg-Fru) are known as the hypotensive compounds of Panax ginseng; however, their efficacy on antihypertension has not been reported yet to our best knowledge. Thus, hypotensive components-enriched fraction of red ginseng (HCEF-RG) was prepared from fine root concentrate (FR) and their antihypertensive effects were investigated in spontaneously hypertensive rats (SHR). Methods: Male SHRs were divided into six groups: control (Wistar Kyoto, SHR); FR 500; FR 1,000; HCEF-RG 500; and HCEF-RG 1,000; samples (mg/kg body weight) were orally administered every day for 8 wk. Blood pressure was monitored at 1 wk, 2 wk, 3 wk, 4 wk, 6 wk, and 8 wk by tail cuff method. At 8 wk after samples administration, mice were killed for the measurement of renin activity (RA), angiotensin-I converting enzyme inhibition, angiotensin II, and nitric oxide (NO) levels in plasma. Results: HCEF-RG with four-fold more Rg3 and 24-fold more Arg-Fru contents was successfully prepared from reacted mixtures of FR and persimmon vinegar (12 times against FR, v/v) at $80^{\circ}C$ for 18 h. Both FR 1,000 and HCEF-RG 1,000 showed lowered systolic blood pressure than SHR control group and HCEF-RG 1,000 group exhibited a significant decrease in diastolic blood pressure. RA was significantly lowered in all treated groups, while angiotensin II did not affect by FR and HCEF-RG treatment. However, angiotensin-I converting enzyme inhibition and NO in FR 1,000 and HCEF-RG 1,000 were significantly increased compared with SHR control group. Conclusion: HCEF-RG is more effective and useful for alleviating hypertension than FR, implying the health benefit of Rg3 and Arg-Fru.

• Journal of Nutrition and Health
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• v.16 no.4
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• pp.243-252
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• 1983

This study was undertaken to invesigate the effect of early nutritional deprivation and environment on neurotransmitter concentrations and behavior in later life. The restoring process of rats fed foods ad libitum after 50% restriction of the casein or the Korean diet during the prenatal and/or the lactating periods was observed. There were two rearing conditions, isolated and enriched, after weaning. Behavioral development was measured by the Y- shaped water maze and the open field test. The neurotransmitters were analyzed after sacrifice at the age of 21 weeks. The results are summarized as follows. 1) The body weight impairment by dietary restriction during the prenatal and lactating periods could be restored within 18 weeks after weaning in case of living in a classical cage. The effect of quantitative restriction was bigger in the Korean diet than in the casein diet. 2) The brain weight was decreased by nutritional deprivation. Environmental enrichment increased it slightly. 3) The concentration of neurotransmitters, norepinephrine, dopamine, and serotonin, were not shown any traces of the dietary restriction at the age of 21 weeks. 4) In the maze test, the deprived rats made more errors than the nourished and the rats fed the Korean diet more than those fed the cascin dict. The environmental enrichment could decrease the number of errors. 5) In the open field test, the dietary deprived groups showed less reaction time, more squares entered in the field, and less number of fecal boli than the nourished among the environmentally isolated rats. However, rats living in the enriched cage without experience of nutritional stress showed the lowest emotionality and the elevated exploratory activity.

• Journal of Ginseng Research
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• v.42 no.1
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• pp.98-106
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• 2018

Panax ginseng has been used since ancient times based on the traditional Asian medicine theory and clinical experiences, and currently, is one of the most popular herbs in the world. To date, most of the studies concerning P. ginseng have focused on specific mechanisms of action of individual constituents. However, in spite of many studies on the molecular mechanisms of P. ginseng, it still remains unclear how multiple active ingredients of P. ginseng interact with multiple targets simultaneously, giving the multidimensional effects on various conditions and diseases. In order to decipher the systems-level mechanism of multiple ingredients of P. ginseng, a novel approach is needed beyond conventional reductive analysis. We aim to review the systems-level mechanism of P. ginseng by adopting novel analytical framework-network pharmacology. Here, we constructed a compound-target network of P. ginseng using experimentally validated and machine learning-based prediction results. The targets of the network were analyzed in terms of related biological process, pathways, and diseases. The majority of targets were found to be related with primary metabolic process, signal transduction, nitrogen compound metabolic process, blood circulation, immune system process, cell-cell signaling, biosynthetic process, and neurological system process. In pathway enrichment analysis of targets, mainly the terms related with neural activity showed significant enrichment and formed a cluster. Finally, relative degrees analysis for the target-disease association of P. ginseng revealed several categories of related diseases, including respiratory, psychiatric, and cardiovascular diseases.

• Journal of Aquaculture
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• v.11 no.4
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• pp.437-447
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• 1998

In mass production of larval rockfish, Sebastes schlegeli, high mortality had been observed frequently. This may be the consequence of the low nutritional quality of the live feeds used. This experiment was designed to find out a suitable diet for the mass production of rockfish larvae. Three kinds of live feeds were tested ; plutei of sea urchin (Hemicentrotus pulcherrimus), L-type rotifers (Brachionus plicatiilis) and Artemia naupii. The latter two were enriched with ${\omega}$-yeast, Spirulina platensis and Super Selco before feeding to rockfish larvae. The sea urchin plutei caused to poor survival and growth rates for larval rockfish, and therefore, they were not seemed as proper feed for rockfish larvae. Enrichments of rotifers and Artemia nauplii with ${\omega}$-yeast, Spirulina platensis, or Super Selco improved survival and growth rate. But, rotifers enriched with Super Selco resulted in better rockfish larvae survival than those enriched with ${\omega}$-yeast. A sudden increase of mortality occurred around 11 days after birth. In this critical period, a shift feed such as Artemia nauplii had been supplemented with rotifers. After this critical transition period, the moratality gradually decreased by feeding Artemia nauplii enriched with PUFA. Feeding of mixed feed with rotifers and Artemia nauplii resulted in better larval survival and growth than those of each live food alone.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.494-499
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• 2009

To improve phenylalanine ammonia lyase (E.C.4.3.1.5-PAL) activity in recombinant Escherichia coli, Some approaches for improving phenylalanine ammonia lyase (PAL) activity in recombinant E. coli were developed following preliminary studies by means of response surface method. The results shown that permeabilization with combination of Triton X-100, cetyl trimethyl ammonium bromide (CTAB), and acetone enriched cellular recombinant PAL activity significantly, which improved over 10-fold as compared with the control (untreat cell), as high as 181.37 U/g. The optimum values for the tested variables were Triton X-100 0.108 g/L, CTAB 0.15 g/L, and acetone 45.2%(v/v). Furthermore, a second-order model equation was suggested and then validated experimentally. It was indicated that addition of surfactants and organic solvents made the cells more permeable and therefore allowed easier access of the substrate to the enzyme and excretion of the product, which increased the rate of transport of L-phenylalanine and trans-cinnamic acids. These improved methods of PAL activity enrichment could serve as a rich enzyme source, especially in the biosynthesis of L-phenylalanine.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.114-119
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• 2011

In this study, two duplex real-time PCR approach with melting curve analysis is presented for the detection of Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp. and Staphylococcus aureus, which are important food-borne bacterial pathogens usually present in fresh and/or minimally processed vegetables. Reaction conditions were adjusted for the simultaneous amplification and detection of specific fragments in the ${\beta}$-glucuronidase (uidA, E. coli), thermonuclease (nuc, S. aureus), hemolycin (hly, L. monocytogenes) and tetrathionate reductase (ttr, Salmonella spp.) genes. Melting curve analysis using a SYBR Green I real-time PCR approach showed characteristic $T_m$ values demonstrating the specific and efficient amplification of the four pathogens; $80.6{\pm}0.9^{\circ}C$, $86.9{\pm}0.5^{\circ}C$, $80.4{\pm}0.6^{\circ}C$ and $88.1{\pm}0.11^{\circ}C$ for S. aureus, E. coli O157:H7, L. monocytogenes and Salmonella spp., respectively. For all the pathogens, the two duplex, real-time PCR was equally sensitive to uniplex real-time PCR, using same amounts of purified DNA, and allowed detection of 10 genome equivalents. When our established duplex real-time PCR assay was applied to artificially inoculated fresh lettuce, the detection limit was $10^3$ CFU/g for each of these pathogens without enrichment. The results from this study showed that the developed duplex real-time PCR with melting curve analysis is promising as a rapid and cost-effective test method for improving food safety.

• BMB Reports
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• v.45 no.1
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• pp.14-19
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• 2012

A feruloyl esterase encoding gene (designated fae6), derived from a leachate metagenomic library, was cloned and the nucleotide sequence of the insert DNA determined. Translational analysis revealed that fae6 consists of a 515 amino acid poly-peptide, encoding a 55 kDa pre-protein. The Fae6 primary structure contained the G-E-S-A-G sequence, which corresponds well with a typical catalytic serine sequence motif (G-x-S-x-G). The fae6 gene was successfully over-expressed in E. coli and the recombinant protein was purified to 8.4 fold enrichment with 17% recovery. The $K_M$ data showed Fae6 has a high affinity to methyl sinapate while thermostability data indicated that fae6 was thermolabile with a half life ($T_{1/2}$) < 30 min at $50^{\circ}C$. High affinity for Fae6 against methyl sinapate, methyl ferulate and ethyl ferulate suggest that the enzyme can be useful in hydrolyzing ferulated polysaccharides in a biorefinery process.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.207-215
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• 2011

An endosulfan degrading bacterial strain, K-1321, was isolated by endosulfan-enrichment culture from a seaside sediment collected at Dadaepo Beach, Busan, Korea. The strain was identified as a Serratia sp. based on the results of morphological, biochemical and 16S rDNA homology analyses. Serratia sp. K-1321 was able to completely degrade 50 ppm endosulfan in culture media and soil within 6 weeks at $25^{\circ}C$. GC/MS analysis revealed that endosulfan diol was an intermediate of the bacterial endosulfan degradation. Considering the above results, we concluded that Serratia sp. K-1321 utilized endosulfan as a carbon source and metabolized endosulfan via a less toxic pathway, such as the formation of endosulfan diol as an intermediate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.2
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• pp.84-88
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• 2008

A bacterium growing on formaldehyde as a sole carbon source was isolated by the dilution method from an enrichment culture containing formaldehyde. The isolated strain, YK-32, was identified as Pseudomonas sp. by morphological, biochemical, and genetic analyses. Pseudomonas sp. YK-32 completely degraded 0.05% formaldehyde within 24 hrs. The isolated strain had a high level of formaldehyde dehydrogenase activity, which is thought to be one of the important factors for formaldehyde degradation, when cells were cultivated in the presence of formaldehyde.