• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.4
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• pp.219-225
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• 2005

We studied the anticancer, antioxidative, ACE inhibitory, antithrombic, and cerebral ischemia inhibitory activities, of low molecular weight substances fractionated from the seasoned and smoked products of skipjack tuna (Euthynus pelamis). Low molecular weight substances fractionated from the liquid extract of seasoned and smoked skipjack tuna powder showed 7 peaks on gel permeation chromatography. Anticancer activity was the highest at Peak 3 $(54.23%)$ followed by Peak 4 $(41.58\%)$. The potency order of antioxidative activity was the highest at Peak 3 $(94.14\%)$ followed by Peak 2 $(82.07\%)$ and Peak 5 $(81.24\%)$. ACE inhibitory activity was the highest at Peak 3 $(67.27\%)$ followed by Peak 5 $(45.62\%)$. But there was weak anti thrombotic effect (PT and APTT) in the low molecular weight substances of the seasoned and smoked products of skipjack tuna. Cerebral ischemia inhibitory activity was the highest at Peak 3 $(80.0\%)$ followed by Peak 5 $(40.0\%)$.

• The Microorganisms and Industry
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• v.20 no.3
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• pp.14-21
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• 1994

Low molecular weight molecules and high molecular weight substances were found to have anti-tumor and immuno-modulating activity. Previously polysaccharides have been received much attention because of adhesives, food additives or animal foods (Whistler et al., 1976). In effort of developing new anti-tumor substances with low toxicity, numerous polysaccharides from yeast, algae, bacteria, higher plants and especially fungi have been investigated for anti-tumor and immuno-modulating activities. Thus the high molecular weight molecule was reported to have anti-tumor activity through host mediated immunity. In this brief article, attention will be paid to polysaccharides which is especially fungal origin.

• Journal of Korean Society on Water Environment
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• v.21 no.2
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• pp.125-131
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• 2005

Natural organic matter(NOM) is defined as the complex matrix of organic material and abundant in natural waters. It affects the performance of unit operations for water purification. Several kinds of analytical indicators such as DOC, specific ultraviolet absorbance(SUVA), apparent molecular weight (AMW), fractionation and high performance size exclusive chromatography(HPSEC) have been used to understand characteristics and variations of NOM. This study aims to evaluate the characteristics of NOM in the Geum River system comprising with stream flows and reservoirs. It was identified that SUVA denoting the portion of humic substance in water ranged within 1.60~3.36. Using resin adsorbents, dissolved organic carbon(DOC) was fractionated into three classes: hydrophobic bases(HOB), hydrophobic acids(HOA) and hydrophilic substances(HI). HI dominates in all samples, collectively accounting for more than 62% of the DOC. HOA was the second dominated fraction and it varied considerably but accounted for about 30% of the DOC. The distribution of high molecular weight(HMW) measured by HPSEC being used to determine the molecular weight distribution of aquatic humic substances was 40.1% and 38.7% in reservoir and stream flow, respectively. The distribution of low molecular weight(LMW) in stream flow was 13.2% higher than that in reservoir. And apparent molecular weight less than 1KDa, which include the molecular weight of hydrophilic organic matter, occupied with 69.2% and 68.2% in stream flow and reservoir, respectively. While the molecular weight of 1 to 100 KDa including humic substances ranged with 18.6% and 21.6% in stream flow and reservoir, respectively. Seasonal variation of refractory dissolved organic carbon was similar to that of SUVA.

• Journal of Crop Science and Biotechnology
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• v.10 no.2
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• pp.117-122
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• 2007

Distributions of physiological inhibitors of a tau-type pumpkin glutathione S-transferase(CmGSTU3) have been investigated in different organs of pumpkin plants, including the onion bulb and water hyacinth root. Inhibitory effects were observed in alcoholic extracts of all plant parts, but the extracts prepared from the roots of either water hyacinth or pumpkin plant showed the highest effect on CmGSTU3 toward 1-chloro-2,4- dinitrobenzene(CDNB). Results of various chromatographies indicated that a number of inhibitory substances were present in the alcoholic extract of each plant organ. Some macromolecules in the plant extracts exhibited inhibitory effects; however, the extracts might contain a large number of unknown low-molecular-weight inhibitory substances. Some of the low-molecular-weight inhibitors in water hyacinth root extract showed characteristics fluoresce under UV light.

• Applied Microscopy
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• v.19 no.2
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• pp.43-58
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• 1989

To investigate the effects of hexavalent chromium on mitochondrial respiration of rat kidney, various hexavalent chromium concentrations were treated, then respiration and electron transfer enzyme activities were measured. Ultrastructural changes at state IV respiration of mitochondria were also observed. Then, to investigate protective role against hexavalent chromium in the body, low-molecular-weight, chromium-binding substances (LMCr) were purified from livers of rabbits 2hr after intravenously administrated with sodium dichromate at a dose of 74mg per kg body weight. And then, respiration rates of mitochondria treated with LMCr, hexavalent chromium containing 0.7mM chromium were measured. Hexavalent chromium decreased state IV respiration rates and electron transfer enzyme activities of mitochondria, and increased labile membrane and swelling. And partial inhibitions of condensed to orthodox conformational change were observed. Respiration rates of mitochondria treated with LMCr containing 0.7mM chromium did not differ from that of the non-treated mitochondria. But respiration rates of 0.7mM hexavalent chromium-treated mitochondria decreased by 42%, compared to non-treated mitochondria. These results suggest that LMCr may play an important role in detoxification of toxic hexavalent chromium.

• Journal of Ginseng Research
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• v.17 no.3
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• pp.210-218
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• 1993

This study was conducted to investigate the effects of Korean ginseng extracts and their fractions on the growth of Saccharomyces cerevsiae and Saccharomyces uvamm, their glucose consumption and alcohol production. The growth of both yeasts were stimulated by ginseng extracts and their water soluble fractions, but were supressed by ether extracts and an n-butanol extracts. Their growth were enhanced considerably by low molecular weight fractions (< 1,000) in water solubles. Similar results were also obtained with glucose consumption by yeasts. Substances increasing the growth and glucose consumption by yeasts proved to be a low molecular weight fractions (<1,000) in water solubles not saponins. The production of n-propyl alcohol by yeast was enhanced by adding ginseng extracts into the media, but that of ism-butyl alcohol was suppressed at same condition.

• 한국균학회소식:학술대회논문집
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• 2016.05a
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• pp.13-13
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• 2016

Insects constitute the largest and most diverse group of animals in the world. They also serve as the hosts or nutrient sources for an immense assemblage of pathogens, parasites, and predators. More than 700 fungal species from 100 genera have adopted an entomopathogenic lifestyle. Although entomopathogenic fungi were studied as only biocontrol agents against a variety of pests in various countries, it has been recently focused their additional roles in nature. They are antagonists to/against plant pathogens, endophytes, and possibly even plant growth promoting agents. The potential antimicrobial effect against fungal plant pathogens by an isolate of entomopathogenic fungi including Beauveria bassiana, Lecanicillium spp., and Isaria fumosorosea have been reported since late 1990s, but wasn't reported pathogenicity of the isolate against pests. Later, a Canadian Lecanicillium sp. isolate and L. longisporium isolated from Vertalec$^{(R)}$ showed simultaneous control effect against both aphid and cucumber powder mildew. Therefore, the antimicrobial activities of 342 fungi isolates collected from various regions and conditions in Korea were evaluated against plant pathogenic fungus Botrytis cinerea using dual culture technique on agar plate. As a result, 186 isolates (54.4%) shown the antifungal activity against B. cinerea. The culture filtrates of selected fungi completely suppressed the growth of the microorganisms, indicating that suppression was due to the presence of antimicrobial substances in the culture filtrate. Mode of action of these fungi against insect involves the attachment of conidia to the insect cuticle, followed by germination, cuticle penetration, and internal dissemination throughout the insect. During infection process, secreted enzymes, proteinous toxins, and/or secondary metabolites secreted by entomopathogenic fungi can be used to overcome the host immune system, modify host behavior, and defend host resources. Recently, secondary metabolites isolated from entomopathogenic fungi have been reported as potential bioactive substances. Generally, most of bioactive substances produced by entomopathogenic fungi have reported low molecular weight (lower than 1,000 g/mol) as peptide and, in contrast the high molecular weight fungal bioactive substances are rare. Most substances based on entomopathogenic fungi were shown antimicrobial activity with narrow control ranges. In our study we analyzed the antimicrobial substances having antagonistic effects to B. cinerea. Antimicrobial substances in our fungal culture filtrates showed high thermostability, high stability to proteolytic enzymes, and hydrophilicity and their molecular weights were differed from substance. In conclusion, entomopathogenic fungi showed pathogenicity against insect pests and culture filtrate of the fungi also shown to antimicrobial activity. In the future, we can use the entomopathogenic fungi and its secondary metabolites to control both insect pest control and plant pathogenic fungi simultaneously.

• Journal of environmental and Sanitary engineering
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• v.22 no.4
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• pp.23-32
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• 2007

Changes in the characteristics of dissolved organic matter was studied at selected stations in the Nakdong river basin using physical and chemical methods. Characteristics of dissolved organic matters were analysed and assessed. Production of disinfection byproducts were also investigated. Distribution of the organic compounds according to the Molecular weight(MW) indicate that MWs higher than 100K were highest with cattle excrement wastewater and MW between 100-10K were highest with waters from forest streams. Low MW compounds (Jess than 1K) were highest with the effluents from environmental facilities. Results of resin fractionation study show that acidic hydrophobic substances(AHS) were dominant in many stations. The values were higher in the samples from mainstreams and sidestreams where the influence of organic matter is higher than the water from environmental facilities. Hydrophilic neutral substances(HoN) such as hydrocarbon, pesticides and detergents were higher in the wastewater treatment facilities. HoN values of water from the forest streams were 4.7% indicating there is no synthetic pollutant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.651-657
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• 1995

The antioxidative activity of each fraction in human milk was examined using H2O2 and FeSO4-induced lipid peroxidation of mouse liver homogenate in order to elucidate the antioxidative substances of human milk. High molecular weight(~>20KD) fraction had more antioxidative effect on lipid peroxidation than low molecular weight(~ <20KD) fraction. Furthermore, the changes of antioxidative enzyme activities were estimated during lactation to study the roles of human milk. The human milk showed high activities of catalase, glutathione(GSH) peroxidase and GSH S-transferase. These results suggest that the antioxidative activities may mostly be attributed to high molecular weight fraction containing catalase, GSH peroxidase and GSH S-transferase.

• The Journal of the Korea Contents Association
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• v.19 no.2
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• pp.277-283
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• 2019

In this study, low molecular weight chitosan (LC) was added to dental cement liquid at 0, 0.5, 1.0, and 2.0 wt% by weight for surface properties and oral bacteria adhesive of dental cement. The evaluated by net setting time and surface properties of surface energy on the surface roughness. The degree of oral bacterial adhesion was assessed using two strains of oral bacteria, S. mutans and E.coli. The results showed that the setting time at the LC0.5 group increased no statistically difference was observed (p<0.05). The surface roughness statically significant LC2.0 group and oral bacteria adhesion experiment results in contrast to the control group LC0, LC-added experimental group showed a somewhat lower adherent surface statistically significant difference was observed (p<0.05). It seems that this LC proved that surface properties and oral bacteria adhesion effect was demonstrated. Therefore, it was suggest that the additional effects of LC and research on a wide range of substances.