• Journal of Microbiology
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• v.39 no.4
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• pp.254-264
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• 2001

Sponges are host organisms for various symbiotic microorganisms such as archaea, bacteria, cyano-bacteria and microalgae. Sponges are also sources of a wide variety of useful natural products like cyto-toxins. antifouling agents, antibiotics, and anti-inflammatory and antiviral compounds, Symbiotic microorganisms is sponges can be sources of various natural products, because metabolites previously ascribed to sponges have recently been demonstrated to be biosynthesized by symbionts. If a symbiotic microorganisms from which some natural products are derived can be cultured, the microorganism could be used in a mass production of the bioactive comopounds. We summarize recent research on iso-lation and cultivation of sponge-symbiotic microorganisms and the symbiotic relationship.

• YAKHAK HOEJI
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• v.45 no.3
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• pp.245-250
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• 2001

Aminoacyl tRNA synthetases of bacteria are known as potential targets for new anti-microbial agents. To isolate new inhibitors of bacterial methionyl-tRNA synthetases from natural sources, a new target-oriented screening system using whole cells which are over-expressing a target enzyme was developed. Approximately 8,000 culture broths of microorganisms from soils were tested by this screening system. Among them, ten culture broths was found to contain inhibitory activity against methionyl -tRNA synthetases of Escherichia coli. For the validation of the screening system, this new method was compared with in vitro enzymatic method. Seven out of 10 culture broths showed inhibitory activity against methionyl-tRNA synthetases of E. coli. This result showed that the new screening system was comparable to the enzyme assay. Thus we believe that our screening system as a new method can be applied for the screening of new antibiotics inhibiting bacterial methionyl-tRNA synthetases from natural products.

• Journal of the Korean Chemical Society
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• v.57 no.2
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• pp.221-226
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• 2013

A series of some novel 2-[5-(substituted phenyl)-[1,3,4]oxadiazol-2-yl]-benzoxazoles were synthesized by using benzoxazole-2-carboxylic acid on reaction with thionyl chloride in presence of ethanol solvent at room temperature gave benzoxazole-2-carbonyl chloride, which is turned into benzoxazole-2-carboxylic acid hydrazide on reaction with hydrazine hydrate in ethanol solvent under reflux. The subsequent treatment of benzoxazole-2-carboxylic acid hydrazide with an appropriate aromatic carboxylic acid in presence of polyphosparic acid under reflux afforded the title compounds. The chemical structures of the newly synthesized compounds were elucidated by their IR, $^1H$ NMR and Mass spectral data analysis. Further the compounds are used to find out their ability towards anti microbial and nematicidal activity.

• KSBB Journal
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• v.27 no.1
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• pp.9-15
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• 2012

Antimicrobial peptides are widely used in various organisms as a defense system against infection. The peptides are lethal towards bacteria and fungi, however have minimal toxicity in mammalian and plant cells. In this aspect, it is considered that antimicrobial peptides are new alternative materials for defensing against microbial infection. Here, we describe overall characteristics of antimicrobial peptides based on the mechanism of action, classification of the peptides, report detection/screening methods and chemical/biological production. It is expected that understanding of innate immune system based on antimicrobial peptides tends to develop novel natural antimicrobial agents, which might be applied for defensing pathogenic microorganisms resistant to conventional antibiotics.

• Korean Journal of Pharmacognosy
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• v.50 no.3
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• pp.159-164
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• 2019

Zanthoxylum Peel is widely used as a common spice for a variety of foods. In the orient, it has also been used as traditional agents for treating diseases such as indigestion. Recently, Zanthoxylum Peel has been reported to have anti-cancer activity, anti-microbial activity, and anti-inflammatory activity. Chemical components are known sanshool compounds and xanthoxylin. In this study, we were carried out to investigate the constituents of inhibiting a drug metabolizing enzyme CYP3A4 from Zanthoxylum Peel. CYP3A4 is known as an enzyme involved in drug metabolism as monooxygenase containing the heme. As a result of experiment, we found that bergapten ($IC_{50}=18.21{\mu}M$) and quercetin ($IC_{50}=17.27{\mu}M$) isolated from EtOAc extract of Zanthoxylum Peel showed remarkable CYP3A4-inhibiting activities. Structures of the isolated active compounds were established by chemical and spectroscopic means.

• Food Science and Industry
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• v.50 no.2
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• pp.27-36
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• 2017

Today, the food packaging industry has a great interest in using active packaging to fresh food product as a solution for the future to positively provide its quality, safety and shelf life. Many researches have extensively studied functional packaging strategies in recently years. Controlled release packaging (CRP) is an innovative packaging technology in the packaging polymer matrix from which can active agents are delivered in a controlled way into the product. CRP technology is well-suited for controlling release of antimicrobial compounds and antioxidants to prevent food degradation reactions such as microbial growth and lipid oxidation. Advances in CRP technology allow food packaging manufacturers to challenge the development of better functional food packaging systems. This overview examines the most recent developments and technologies of active packaging for applying the food industry. The scope of this article has mainly been focused on controlled releasing systems.

• Journal of Sensor Science and Technology
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• v.32 no.4
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• pp.213-218
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• 2023

Triboelectric nanogenerators (TENGs) have emerged as a highly promising energy harvesting technology capable of harnessing mechanical energy from various environmental vibrations. Their versatility in material selection and efficient conversion of mechanical energy into electric energy make them particularly attractive. TENGs can serve as a valuable technology for self-powered sensor operation in preparation for the IoT era. Additionally, they demonstrate potential for diverse applications, including energy sources for implanted medical devices (IMDs), neural therapy, and wound healing. In this review, we summarize the potential use of this universally applicable triboelectric energy harvesting technology in the disinfection and blocking of pathogens. By integrating triboelectric energy harvesting technology into human clothing, masks, and other accessories, we propose the possibility of blocking pathogens, along with technologies for removing airborne or waterborne infectious agents. Through this, we suggest that triboelectric energy harvesting technology could be an efficient alternative to existing pathogen removal technologies in the future.

• The Plant Pathology Journal
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• v.40 no.3
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• pp.322-328
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• 2024

Soybean (Glycine max), a crucial global crop, experiences yearly yield reduction due to diseases such as anthracnose (Colletotrichum truncatum) and root rot (Fusarium spp.). The use of fungicides, which have traditionally been employed to control these phytopathogens, is now facing challenges due to the emergence of fungicide-resistant strains. Streptomyces bacillaris S8 strain S8 is previously known to produce valinomycin t through a nonribosomal peptide synthetase (NRPS) pathway. The objective of this study was to evaluate the antifungal activity of S. bacillaris S8 against C. truncatum and Fusarium sp., assessing its efficacy against soybean pathogens. The results indicate that strain S8 effectively controlled both above-ground and underground soybean diseases, using the NRPS and NRPS-related compound, suggesting its potential as a biological control in plant-microbe interactions. These findings underscore the pivotal role of the stain S8 in fostering healthy soybean microbial communities and emphasize the significance of microbiota structure studies in unveiling potent biocontrol agents.

• Korean Journal of Poultry Science
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• v.8 no.1
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• pp.7-14
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• 1981

The experiment using Anake broiler strain chicks was conducted to study the effort fungistatic agents on microbial counts, Ins of nutrient, growth rate and feed efficiency of the broiler. Feed was adjusted to 12% and 15% moisture level during hot and high humidity season and sorbic acid at the level of 0.02%, 0.04% and Ca-propionic acid at the level 0.1% 0.2% was added. The results obtained were as follows. 1, The Addition of fungistatic agents could slightly reduce mold and yeast counts. The highest effect on inhibition of mold and yeast counts was observed for the addition of sorbic acid at 0.04% level to the fled contained 15% moisture. 2, Approximately 14% starch loss of ground corn was observed from the fred contained 15% moisture and the loss could be diminished to 3-7% by the addition of fungistatic agents with the superior effect of sorbic acid to Ca-propionic acid. 3. Approximately 15% fat loss was detected when high moisture fled was und and this was reduced to 7% by the addition of 0.04% sorbic acid to the feed. 4. Significantly higher growth rate (p＜0.05) during starter period was observed for low moisture feed added by sorbic acid compared with that for high moisture diet without fungistatic agents or with Ca-propionate at the level of 0.1%. 5. Significantly lower feed efficiency (p＜0.05) during starter period of high moisture feed without fungistatic agents was observed; hower no significant different response was detected by either moisturer level of kinds and levels of fungistatic agents used. 6. Significantly higher growth rate (p＜0.05) during finisher period of lower moisture feed with 0.04% sorbic acid was observed compared with that of high moisture fled without fungistatic agents or the feed added by 0.1% Ca-propionate level. 7. Significantly higher feed efficiency (p＜0.05) during finisher period of low moisture feed added by sorbic acid 0.02% or 0.04% level was found compared with that of high moisture feed without fungistatic agents and low moisture feed added by Ca-propionate at the level of 0.1% or 0.2%. 8. Mort bacteria, mold and yeast were observed in the ceca than in small intestine. The. moisture content of dict had no effect on intestinal microfloral counts. However, numbers of mold and yeast of intestine could slightly be reduced by fungistatic agents administration. 9. Nothing but encephalomalacia to chicks fed feed contained 15% moisture without addition of fungistatic agents was observed. In conclusion, addition of either sorbid acid at 0.04% level and Ca-propionate at 0.2% level to high moisture feed or reduced moisture level to 12% could be con-sidered more effective to enhance growth rate and fled efficiency of broilers during summer period.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.258-266
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• 2014

Sweet potato soju (SPS), a form of traditional distilled alcoholic liquor in Korea, is manufactured by the distillation of fermented broth under normal pressure, thus providing it for a uniquely smooth taste infused with the flavor of sweet potato. After distillation, the lees of SPS is produced as by-product and discarded. In this study, the ethanol and hot water extracts of lees of SPS, and their subsequent organic solvent fractions using hexane, ethylacetate (EA), butanol, and water residue were prepared in an effort at the efficient re-use of the lees of SPS. The ethanol extraction yield was 1.36-fold higher than that of the hot water extraction, and the EA fraction revealed the highest total polyphenol content among the solvent fractions. The various extracts and solvent fractions did not demonstrate hemolytic activity at up to 0.5 mg/ml concentrations against human red blood cells. In the bioactivity assay, only the EA fraction displayed a broad spectrum of anti-microbial activity against different pathogenic and food spoilage bacteria, and demonstrated significant anti-coagulation activity by inhibitions of thrombin, prothrombin and blood coagulation factors. Furthermore, only the EA fraction from the hot water extract of the lees of SPS showed anti-platelet aggregation activity, which is comparable to aspirin (a commercially available drug). Our results suggest that the EA fraction of the hot water extract prepared from the lees of SPS has a high potential as a novel resource for anti-microbial and anti-thrombosis agents.