• Microbiology and Biotechnology Letters
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• v.52 no.3
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• pp.233-254
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• 2024

The microorganisms that live under extreme conditions on Earth are known as extremophiles. They possess an extraordinary capability to endure extreme conditions, including salinity, temperature variations, pH, desiccation, and nutrient scarcity, among others. These organisms, including a vast array of bacteria, eukarya, and archaea, have evolved specialized structural and functional adaptations that make them capable of thriving in extremely selective environments in such a way that they showcase remarkable adaptations that push the limits of what we consider habitable. This capability results in valuable compounds with great potential for developing novel pharmaceuticals and biotechnological innovations. The present review paper aims to summarize current knowledge on the diversity of extremophilic microorganisms and the adaptive strategies employed to face such a range of extreme conditions. Particular attention will be given to temperature, salinity, pH, and desiccation adaptation. The review also highlights their potential applications, specifically focusing on pharmaceutical and biotechnological applications.

• ALGAE
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• v.18 no.2
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• pp.157-167
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• 2003

Effect of the effluent of the sewage and wastewater plants on the algal growth was investigated from the 19 plants located in the Nakdong river basin. Most of the samples showed high values of the algal growth potential (AGP) when they were mixed with natural river water at 20% of final concentration. At 20% of the mixing ratio, the mixed effluents of sewage and wastewater showed 3.5 and 1.8 times higher AGP than those of the natural river water. The higher AGP values are attributable to the high contents of phosphorus and ammonium in the effluent. The mixing ratio of effluents of the discharge/river flow was highest in the Kumho River (42.8%) followed by the middle of Nakdong River (22.7%), Kam Stream (13.9%), Byungsung Stream (13.3%), Yangsan Stream (7.9%), and Young River (5.4%). Comparison of the trophic state of the effluents with natural river water indicated that the effluents showed higher trophic values than natural water. Concentrations of total phosphorus, total nitrogen and conductivity in the effluents were 12.3, 4.9 and 5.3 times higher than the those found in natural river water respectively. The AGP values were highly related with the trophicity of the water especially on the concentrations of phosphate and ammonium. Toxicities of the treated sewage water, wastewater and livestock waste water tested by the luminescent bacteria, Vibrio fischerii were generally low.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.510-514
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• 2011

Photodissociation dynamics of allyl alcohol ($H_2C$=CH-$CH_2OH$) has been investigated at 205 - 213 nm along the UV absorption band by measuring rotationally-resolved laser-induced fluorescence spectra of OH radicals. Observed energy partitioning of the available energy among products at all photon energies investigated was similar and the barrier energy for OH production is about 574.7 kJ/mol from the OH yield measurements. The potential energy surfaces for the $S_0$, $T_1$, and $S_1$ excited states along the dissociation coordinate were obtained by ab initio quantum chemical calculations. The observed energy partitioning was successfully modeled by the "barrier-impulsive model" with the reverse barrier and the geometry obtained by the calculated potential energy surfaces. The dissociation takes place on the $T_1$ excited state potential energy surface with an energy barrier in the exit channel and a large portion of the photon energy is distributed in the internal degrees of freedom of the polyatomic products.

• Natural Product Sciences
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• v.17 no.3
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• pp.250-255
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• 2011

The immune system is finely balanced by the activities of pro-inflammatory and anti-inflammatory mediators or cytokines. Unregulated activities of these mediators can lead to the development of various inflammatory diseases. A variety of safe and effective anti-inflammatory agents are available with many more drugs under development. Of the natural compounds, the sesquiterpenes (nootkatone, ${\alpha}$-cyperone, valencene and ${\alpha}$-selinene) isolated from C. rotundus L. have received much attention because of their potential antiinflammatory effects. However, limited studies have been reported regarding the influence of sesquiterpene structure on anti-inflammatory activity. In the present study, the anti-inflammatory potential of four structurally divergent sesquiterpenes was evaluated in lipopolysaccaride (LPS)-stimulated RAW 264.7 cells, murine macrophages. Among the four sesquiterpenes, ${\alpha}$-cyperone and nootkatone, showed stronger anti-inflammatory and a potent NF-${\kappa}B$ inhibitory effect on LPS-stimulated RAW 264.7 cells. Molecular analysis revealed that various inflammatory enzymes (iNOS and COX-2) were reduced significantly and this correlated with downregulation of the NF-${\kappa}B$ signaling pathway. Additionally, electrophoretic mobility shift assays (EMSA) elucidated that nootkatone and ${\alpha}$-cyperone dramatically suppressed LPS-induced NF-${\kappa}B$-DNA binding activity using 32Plabeled NF-${\kappa}B$ probe. Hence, our data suggest that ${\alpha}$-cyperone and nootkatone are potential therapeutic agents for inflammatory diseases.

• Journal of Microbiology and Biotechnology
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• v.34 no.6
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• pp.1239-1248
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• 2024

Peatlands are marginal agricultural lands due to highly acidic soil conditions and poor drainage systems. Drought stress is a big problem in peatlands as it can affect plants through poor root development, so technological innovations are needed to increase the productivity and sustainability of upland rice on peatlands. Rhizobacteria can overcome the effects of drought stress by altering root morphology, regulating stress-responsive genes, and producing exopolysaccharides and indole acetic acid (IAA). This study aimed to determine the ability of rhizobacteria in upland rice to produce exopolysaccharides and IAA, identify potential isolates using molecular markers, and prove the effect of rhizobacteria on viability and vigor index in upland rice. Rhizobacterial isolates were grown on yeast extract mannitol broth (YEMB) medium for exopolysaccharides production testing and Nutrient Broth (NB)+L-tryptophan medium for IAA production testing. The selected isolates identify using sequence 16S rRNA. The variables observed in testing the effect of rhizobacteria were germination ability, vigour index, and growth uniformity. EPS-1 isolate is the best production of exopolysaccharides (41.6 mg/ml) and IAA (60.83 ppm). The isolate EPS-1 was identified as Klebsiella variicola using 16S rRNA sequencing and phylogenetic analysis. The isolate EPS-1 can increase the viability and vigor of upland rice seeds. K. variicola is more adaptive and has several functional properties that can be developed as a potential bioagent or biofertilizer to improve soil nutrition, moisture and enhance plant growth. The use of rhizobacteria can reduce dependence on the use of synthetic materials with sustainable agriculture.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8007-8018
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• 2014

Cervical cancer is the most common gynecologic malignancy worldwide and development of new therapeutic strategies and anticancer agents is an urgent priority. Plants have remained an important source in the search for novel cytotoxic compounds and several polyphenolic flavonoids possess antitumor properties. In this review article, data about potential anticarcinogenic activity of common natural flavonoids on various human cervical cancer cell lines are compiled and analyzed showing perspectives for the use of these secondary metabolites in the treatment of cervical carcinoma as well as in the development of novel chemotherapeutic drugs. Such anticancer effects of flavonoids seem to differentially depend on the cellular type and origin of cervical carcinoma creating possibilities for specific targeting in the future. Besides the cytotoxic activity per se, several flavonoids can also contribute to the increase in efficacy of conventional therapies rendering tumor cells more sensitive to standard chemotherapeutics and irradiation. Although the current knowledge is still rather scarce and further studies are certainly needed, it is clear that natural flavonoids may have a great potential to benefit cervical cancer patients.

• Culinary science and hospitality research
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• v.22 no.6
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• pp.14-23
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• 2016

This purpose of this study is to examine the antioxidant and antimicrobial activities of Persicaria hydropiper L. extract in 70% ethanol and in water, a medicinal herb, as an effort to examine the potential of medicinal herbs for development of antioxidants and natural preservative substitutes. The total poly-phenol content in the 70% ethanol extract and in the water extract were 19.88 mg/g and 7.46 mg/g, respectively. The DPPH radical scavenging activity was 90.99% and 64.98% in the 70% ethanol extract and water extract, in which 70% ethanol extract showed a higher activity. The antioxidant effect of Persicaria hydropiper L. extract appears to be very good and due to its excellent growth inhibitory effect on food-poisoning-causing microorganisms in the food, it is thought to be utilized as a potential natural preservative substitute in many areas.

• YAKHAK HOEJI
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• v.14 no.3_4
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• pp.51-53
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• 1970

Alcohol extracts of six plant namely Coix agrestis L$_{OUREIRO}$, Chloranthus Japonicus (Siebi) N$_{AKAI}$, Ajuga Spectabilis N$_{AKAI}$, Juglans mandsuria Max., Cirsium Macki var Ussuriense $K_{ITA}$ and Sasamorpha Purpurascense (Hack) N$_{AKAI}$ were subjected to the screening tests for anti-tumor activities against SN-36 Leukemia, Sarcoma 180 and Ehrlich ascites carcinoma. Of the six extracts, Ajuga Spectabilis N$_{AKAI}$ and Coix agrestis L$_{OUREIRO}$ were found to be potential in survival effect of tumor transplanted mice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.4
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• pp.241-244
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• 2000

This experiment was conducted to evaluate the effect on evapotranspiration and yield of soybean according to different soil water conditions, and to find the optimum time and amount for irrigation in soybean cultivation. The difference between potential evapotranspiration (PET) and maximum evapotranspiration (MET) during growing season of soybean planted in lysimeter was higher during reproductive stage than during vegetative one. The maximum crop coefficient was obtained at beginning seed stage of soybean. Soil water coefficient of irrigation treatment was higher than that of non-irrigation treatment during soybean growth stage in field experiment. Grain yield was highest in lysimeter due to its high water use efficiency and evapotranspiration rate.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.6
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• pp.32-41
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• 1999

Natural gas is an attractive fuel in view of environment benefits due to its flow carbon-to-hydrogen ratio. However, its compositions and properties are varied depending upon production regional groups. Therefore, study on the combustion characteristics of natural gas engines with a variety of compositions has been demanded for the efficient application of gas engines. This study aims to investigate the effects of gas composition on engine combustion characteristics. It was found that , by controlling an engine with fixed fuel nozzle area, power and heat release were subject to Wobbe Index. And at fixed excess air ratios, power and heat release were subject to low heating value of unit mixture . In addition, in case of constant nozzle area, combustion duration was found to be inversely proportional to CP(Combustion Potential), and the condition of fixed excess air ratios showed no change in combustion duration, regardless of CP.