• Journal of Microbiology and Biotechnology
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• v.19 no.1
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• pp.42-50
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• 2009

Fifty-four Pectobacterium carotovorum subsp. carotovorum strains isolated in Korea were characterized by a spectrum of antibacterial activities against 7 indicator strains chosen to represent various regions and host plants. All P. carotovorum subsp. carotovorum isolates tested could be grouped into 4 classes depending on the pattern of antibacterial substance production. All tested strains had DNA fragment(s) homologous to the genes encoding carotovoricin and 21 of them had genes homologous to DNA invertase. Sixteen strains had genes homologous to the genes encoding carocin S1. Several isolates produced antibacterial substances active against strains in Brenneria, Pantoea, and Pectobacterium genera that belonged formerly to the genus Erwinia. Strains in Pseudomonas or Xanthomonas sp. were not sensitive to the antibacterial substances produced by P. carotovorum subsp. carotovorum, except for X. albilineans that was sensitive to antibacterial substances produced by most strains in P. carotovorum subsp. carotovorum and P. betavasculorum KACC10056. These results demonstrated the diverse patterns of antibacterial substance production and the possibility of the existence of new antibacterial substance(s) produced by P. carotovorum subsp. carotovorum isolated in Korea.

• Microbiology and Biotechnology Letters
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• v.5 no.1
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• pp.36-45
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• 1977

A piscicidal substance was isolated from the culture medium of Streptomyces umbrosus by avicel column chromatography and avicel thin layer chromatography after extration with chroloform. Bluegreen fluorescence was emitted under UV irradiation. Factors which govern toxin production and nutrition requirement for high toxin titres were observed. Nutritional uptake for toxin production was not curresponded with that for cell growth. Alanine, valine, serine asparagine, arginine, histidine, urea and sodium nitrate as a carbon source and glucose, mannose, rhamnose, xylose, arabitol and starch as a carbon source were recognized as a favorable nutrient for high toxin production. Magnesium was essential factor whereas vitamins were not of effective. Most of toxin was formed simultaneously with cell growth in esponential phase. Maximal production was observed for six day culture at 3$0^{\circ}C$. Tissues of gill, kidney and pnacreas in Cyprinus carpio were denatured extreamly after treating with the substance. Atrophied nucleous, indented membrane and degradated cytoplasm with necrotic affectness were noted on each tissue. The chemical formula of the substance was designated as $C_{38}$ $H_{66}$ $NO_4$.

• The Korean Journal of Food And Nutrition
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• v.8 no.1
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• pp.43-49
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• 1995

This studies were carried out to purification and seperation of chitooligosaccharides which containing excellent biological active substance. After deacetylation of chitosan (DAC%), DAC-45%, DAC-70%, DAC-95% and DAC-99% were used substrates and hydrolyzed by chitosanase (Bacillus pumilus BN-262) DAC-99% has excellent hydrolyzate which contained several chitooligosaccharides. Therefore, chitosan was hydrolyzed DAC-90 as substrate by chitosanase, and then purified and seperated of chitooligosaccharides Gel filteration and HPLC. This oligosaccharides composed with GlcN0, GlcN2, GlcN3, Glc5 and GlcN6.

• Preventive Nutrition and Food Science
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• v.10 no.1
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• pp.95-102
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• 2005

The term pharmacognosy as applied to a constituent scientific discipline of Korean Medical Food (KMF) has been in use for nearly several years, and it refers to studies on the pharmacological properties of natural products foods. During the last half of the 20th century, pharmacognosy for KMF evolved from being a descriptive botanical subject to one having a more chemical and biological focus. At the beginning of the 21st century, teaching pharmacognosy for KMF teaching in academic culinary arts and natural healing institutions has been given new relevance as a result of the explosive growth in the use of herbal foods (health foods) in modern KMF practice. In turn, pharmacognosy for KMF research areas are continuing to expand, and now include aspects of cellular and molecular biology in relation to natural products, ethnobotany and phytotherapy, in addition to the more traditional analytical method development and phytochemistry. Examples are provided in this review of promising bioactive compounds obtained in two multidisciplinary natural product KMF development and discovery projects, aimed at the elucidation of new plant-derived cancer chemotherapeutic agents and novel cancer chemopreventives, respectively. The systematic study of KMF offers pharmacognosy groups an attractive new area of research, ranging from investigating the biologically active principles of KMF and their mode of action and potential active substance interactions, to sanitary and quality control, and involvement in clinical trials.

• Korean Journal of Clinical Pharmacy
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• v.21 no.2
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• pp.49-56
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• 2011

The family of bile acids belongs to a group of molecular species of acidic steroids with very peculiar biological characteristics. They are synthesized by the liver from cholesterol through several complementary pathways and secreted into small intestine for the participation in the digestion and absorption of fat. The bile acids are mostly confined to the territories of the so-called enterohepatic circulation, which includes the liver, the biliary tree, the intestine and the portal blood with which bile acids are returned to the liver. In patients with bile acid malabsorption, the amount of primary bile acids in the colon is increased compared to healthy controls. Although the increase in the secondary bile acids including deoxycholic acid, is reported to have the potency to affect tumorigenesis in gastrointestinal tracts, there is no firm evidence that clinically relevant concentrations of the bile acids induce cancer. The list of their physiological roles, as well as that of the pathological processes is long and still not complete. There is no doubt that many new concepts, pharmaceutical tools and pharmacological uses of bile acids and their derivatives will emerge in the near future.

• Journal of Applied Biological Chemistry
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• v.49 no.3
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• pp.110-113
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• 2006

Prolyl endopeptidase (PEP, EC 3.4.21.26, also referred to as prolyl oligopeptidase) degrades proline containing, biologically active neuropeptides such as vasopressin, substance P and thyrotropin-releasing hormone by cleaving peptide bonds on carboxyl side of prolyl residue within neuropeptides of less than 30 amino acids. Evaluation of PEP levels in postmortem brains of Alzheimer's disease patients revealed significant increases in PEP activity. Therefore, a specific PEP inhibitor can be a good candidate of drug against memory loss. Upon our examination for PEP inhibitory activity from micronutrients, ascorbic acid (vitamin C) showed small but significant PEP inhibition (13% PEP inhibition at $8{\mu}g{\cdot}ml^{-1}$). Palmitic acid showed almost no PEP inhibition. However, 6-O-palmitoyl ascorbic acid ($\underline{1}$) showed 70% PEP inhibition at $8{\mu}g{\cdot}ml^{-1}$ indicating that hydrophobic portion of the compound $\underline{1}$ may facilitate the inhibitory effect. $IC_{50}$ value of compound $\underline{1}$ was $12.6{\pm}0.2{\mu}M$. The primary and secondary Lineweaver Burk and Dixon plots for compound $\underline{1}$ indicated that it is a non-competitive inhibitor with inhibition constant (Ki) value of $23.7{\mu}M$.

• Journal of Applied Biological Chemistry
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• v.60 no.3
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• pp.265-269
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• 2017

Environment-friendly, commercially-available agricultural products were investigated for antimicrobial activity against Sclerotinia sclerotiorum, as a pathogen of sclerotium disease. Then ${\beta}$-thujaplicin from Chamaecyparis obtuse was investigated for antifungal activity against six kinds of pathogenic fungi. It showed a statistically significant (p <0.001) growth inhibition effect on Sclerotinia sclerotiorum as a pathogen of sclerotium disease, Rhizoctonia solani AG-4 as a pathogen of damping off, Phytophthora capsici as a pathogen of phytophthora blight, and Colletotrichum coccodes as a pathogen of anthracnose at a concentration of 50 ppm and on Stemphylium solani as a pathogen of spotting disease and Alternaria alternata as a pathogen of black mold at a concentration of 100 ppm. In conclusion, these results indicate that it may be possible to develop environment-friendly agricultural products using ${\beta}$-thujaplicin compounds.

• Korean Journal of Pharmacognosy
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• v.26 no.2
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• pp.122-129
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• 1995

The study on phytochemical analysis and the biological activity of Kalopanacis Cortex was carried out in this research. As a phytochemical result, liriodendrin as a lignan glycoside was isolated and characterized. Two subfraction separated from the acidic substance of $CHCl_3$ fraction were saturated and unsaturated fatty acid, respectively. Saturated fatty acid mixture identified from GC-MS tool was as follows: palmitic acid, stearic acid, arachidic acid, heneicosanoic acid, docosanoic acid, tricosanoic acid, tetracosanoic acid, pentacosanoic acid, hexacosanoic acid and octacosanoic acid. Unsaturated fatty acid was found to be linoleic acid on the basis of spectroscopic method. An active principle of liriodendrin exhibited significant antihepatotoxic activity but failed to show a considerable antiedemic activity. In this paper, the result of writhing test on liriodendrin was also described.

• Journal of Korean Biological Nursing Science
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• v.24 no.2
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• pp.77-85
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• 2022

Purpose: Aging process comes with cognitive impairment due to decreased neuronal cell number, activity, and neuronal circuit. Alteration of inhibitory neurons contributes to cognitive impairment in normal aging and is responsible for disrupting the excitation/inhibition balance by reducing the synthesis of gamma-aminobutyric acid (GABA). Morus nigra (Mulberry) is a natural physiologically active substance that has been proven to have anti-oxidant, anti-diabetic, and anti-inflammatory effects through many studies. This study aimed to evaluate the effects of the mulberry extract (ME) on cognitive function through anti-oxidant enzyme and GABAergic neuronal activity in aged rat brain. Methods: Sprague Dawley rats were randomly assigned as the young group (8 weeks, n= 8), aging group (67 weeks, n= 8), and aging+ mulberry extract group (67 weeks, n= 8). The aging+ mulberry extract group was orally administered 500 mg/kg/d mulberry extract for 6 weeks. Results: The aging+ mulberry extract group improved spatial and short-term memory. The antioxidant potential of ME increased the expression of superoxide dismutase-1 (SOD-1) and decreased inducible nitric oxide synthase (iNOS). Also, the aging+ mulberry extract group significantly increased the expression of GABAergic interneuron in hippocampus cornu ammonis1 (CA1) compared to the aging group. Conclusion: The number of GABAergic inhibitory interneurons was deceased and memory functions in the aging process, but those symptoms were improved and restored by mulberry extract administration.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.509-516
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• 2007

Starters of lactic acid bacteria(LAB) were isolated from the commercial yoghurt products and the four isolates have been studied on their identification and some physiological characteristics. For the purpose of identification, microscopic examination, API test, and 16s rRNA gene sequencing were conducted. Isolate A from a yogurt product of local dairy company A was shown to be Gram-positive rod-shaped bacterium. All strains isolated were turned out to be as Lactobacillus paracasei by using a API 50 CHL kit. In contrast, isolate A was identified as a strain of Lactobacillus helveticus based on the 16S rRNA sequencing data, and L. casei ssp. casei for both B and D and L. paracasei for C. All the isolates survived the simulated gastric juice, pH 2.0 within 3 hours and sharply decreased in viability so that no viable cell was observed after 4.5 hours incubation. In addition, the four isolated strains were almost identical in antibiotic susceptibility to six different kinds of antibiotics including erythromycin ($15\;{\mu}g$), ampicillin ($10\;{\mu}g$), gentamycin ($10\;{\mu}g$), neomycin ($30\;{\mu}g$), but rather resistant to colistin ($10\;{\mu}g$) and streptomycin ($10\;{\mu}g$). It was noteworthy that four isolates were confirmed to produce antibacterial substance against foodborne pathogens of Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli 0157:H7 as test organisms based on the inhibitory zones on an MRS soft agar medium. At presence, the inhibitory factor is unknown so that further studies are required to ascertain the active factor responsible for the inhibitory activities.