• Molecules and Cells
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• v.46 no.7
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• pp.451-460
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• 2023

Animals generally prefer nutrients and avoid toxic and harmful chemicals. Recent behavioral and physiological studies have identified that sweet-sensing gustatory receptor neurons (GRNs) in Drosophila melanogaster mediate appetitive behaviors toward fatty acids. Sweet-sensing GRN activation requires the function of the ionotropic receptors IR25a, IR56d, and IR76b, as well as the gustatory receptor GR64e. However, we reveal that hexanoic acid (HA) is toxic rather than nutritious to D. melanogaster. HA is one of the major components of the fruit Morinda citrifolia (noni). Thus, we analyzed the gustatory responses to one of major noni fatty acids, HA, via electrophysiology and proboscis extension response (PER) assay. Electrophysiological tests show this is reminiscent of arginine-mediated neuronal responses. Here, we determined that a low concentration of HA induced attraction, which was mediated by sweet-sensing GRNs, and a high concentration of HA induced aversion, which was mediated by bitter-sensing GRNs. We also demonstrated that a low concentration of HA elicits attraction mainly mediated by GR64d and IR56d expressed by sweet-sensing GRNs, but a high concentration of HA activates three gustatory receptors (GR32a, GR33a, and GR66a) expressed by bitter-sensing GRNs. The mechanism of sensing HA is biphasic in a dose dependent manner. Furthermore, HA inhibit sugar-mediated activation like other bitter compounds. Taken together, we discovered a binary HA-sensing mechanism that may be evolutionarily meaningful in the foraging niche of insects.

• Korean Journal of Organic Agriculture
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• v.5 no.2
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• pp.141-152
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• 1997

This experiment was conducted to know the effects of foliar applicated bio-enzyme on the early growth of cucumber and red pepper seedlings. Bio-enzyme was manufactured by the culture and proliferation of Bacillus genus and foliar applicated by the concentration of 0.075, 0.15, 0.3 g.$\ell$-1. Foliar application of bio-enzyme had great influenced to the early growth both cucumber and red pepper seedlings. Optimum concentrations of bio-enzyme applicated for the growth of plant height were determined as of 0.075 g.$\ell$-1 in cucumber but in red pepper seedlings 0.15g.$\ell$-1 was more favored. However, foliar application of 0.15g.$\ell$-1 of bio-enzyme was recommended for both cucumber and red pepper seedlings. Especially, leaf area and total dry weight which are main indices of good seedling were highest in the plot of standard concentrations(0.15g.$\ell$-1)of bio-enzyme.

• Biomolecules & Therapeutics
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• v.13 no.1
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• pp.41-47
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• 2005

The study was conducted to determine whether oak wood vinegar extract influences blood alcohol concentration and hangover syndrome in healthy volunteers. 2% wood vinegar extract was effective to inhibit increase of blood alcohol concentration after alcohol intake and showed significantly different (P<0.1) compared to placebo. By result of questionnaire of volunteers, wood vinegar extract showed effects improving hangover syndrome. In comparative study about blood alcohol concentration and hangover syndrome of wood vinegar extract and other extract that hangover improvement effect was reported, average maximum blood alcohol concentration was lowered in those taking wood vinegar extract than those taking other extract. At drinking completion 210minutes (T210), blood alcohol concentration of those taking wood vinegar extract was the lowest by 0.063% compared with other extract but was not significantly different between in those taking wood vinegar extract and in those taking other extract. However, wood vinegar extract's experimental group was the highest by 0.462 in decrement rate of blood alcohol concentration and, when did P<0.1 by significance level, indicated difference that mean statistically compared to placebo group uniquely. At those taking wood vinegar extract, the improvement rate and the aggravation rate of hangover syndrome was each 87%, 2%. Thus it was concluded that wood vinegar extract showed excellent alcohol oxidation and was effective in hangover improvement.

• Journal of Korean Society on Water Environment
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• v.32 no.3
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• pp.303-309
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• 2016

This study aimed to assay the biological removal of TDS (total dissolved solids) from RO (reverse osmosis) rejected water. Following bio-sorption of TDS with AGS (aerobic granular sludge), the effects of TDS on biological nitrogen removal were examined. The bio-sorption of TDS after AGS treatment was confirmed by checking for TDS removal efficiency and surface analysis of microorganisms with SEM and EDS. Then, the effects of TDS on biological nitrogen removal and the denitrification efficiency were evaluated using the MBR reactor. According to the results, the bio-sorption of TDS with AGS was 0.1 mg TDS/mg AGS, and we confirmed that the microorganism surfaces had adsorbed the TDS. Biological nitrogen removal efficiency was measured at inhibiting denitrification at 4,000 mg/L of TDS-injected material. Based on this study, it is necessary to pretreat TDS-containing RO rejected water and to maintain TDS concentration lower than a specific value (≤4,000 mg/L), when considering biological nitrogen removal.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.466-468
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• 2006

The antimicrobial effect of a novel flavonoid (7-O-butyl naringenin) on Helicobacter pylori ATCC 26695 and its inhibitory effects on the urease activity of the strain were evaluated by comparing with quercetin and naringenin. H. pylori was cultured with brain heart infusion supplemented with 5% horse serum at $37^{\circ}C$ under 10% $CO_2$ atmosphere and the inhibitory effects of flavonoids against the strain were detected using micro-plate methods. During 12 hr of incubation time, the optical densities of phenol red reduced (pink color) in the urea broth by producing ammonia were detected at 560 nm with a spectrophotometer. The results indicated that both quercetin and 7-O-butyl naringenin were effective against the growth of H. pylori. Moreover, inhibitory effect of 7-O-butyl naringenin on the growth of H. pylori was about two-fold higher than quercetin at the same concentration. With regard to H. pylori urease activity, 7-O-butyl naringenin had a greater inhibitory effect than did naringenin or quercetin at the same concentration.

• Journal of environmental and Sanitary engineering
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• v.24 no.4
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• pp.102-111
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• 2009

In this study, Particulate carbon were determined from 1990 to 1995. The annual variation were investigated. The sampling was carried out using high volume air sampler. Average concentrations of EC and OC during the yellow sand event were $25.70{\mu}g/m^3$ and $13.91{\mu}g/m^3$, respectively, $22.10{\mu}g/m^3$ and $10.33{\mu}g/m^3$ during the non-yellow sand event. TC concentration of TSP were 10.7% during the yellow sand event and 20.6% during the non-yellow sand event. Average concentration rate of EC and OC of TC were 64.9% and 35.1%, respectively during the yellow sand event, 67.6% and 32.4% during the non-yellow sand event.

• Journal of Microbiology and Biotechnology
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• v.34 no.3
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• pp.562-569
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• 2024

Xanthomonas oryzae pv. oryzae (Xoo) causes a devastating bacterial leaf blight in rice. Here, the antimicrobial effects of ᴰ-limonene, ᴸ-limonene, and its oxidative derivative carveol against Xoo were investigated. We revealed that carveol treatment at ≥ 0.1 mM in liquid culture resulted in significant decrease in Xoo growth rate (> 40%) in a concentration-dependent manner, and over 1 mM, no growth was observed. The treatment with ᴰ-limonene and ᴸ-limonene also inhibited the Xoo growth but to a lesser extent compared to carveol. These results were further elaborated with the assays of motility, biofilm formation and xanthomonadin production. The carveol treatment over 1 mM caused no motilities, basal level of biofilm formation (< 10%), and significantly reduced xanthomonadin production. The biofilm formation after the treatment with two limonene isomers was decreased in a concentration-dependent manner, but the degree of the effect was not comparable to carveol. In addition, there was negligible effect on the xanthomonadin production mediated by the treatment of two limonene isomers. Field emission-scanning electron microscope (FE-SEM) unveiled that all three compounds used in this study cause severe ultrastructural morphological changes in Xoo cells, showing shrinking, shriveling, and holes on their surface. Moreover, quantitative real-time PCR revealed that carveol and ᴰ-limonene treatment significantly down-regulated the expression levels of genes involved in virulence and biofilm formation of Xoo, but not with ᴸ-limonene. Together, we suggest that limonenes and carveol will be the candidates of interest in the development of biological pesticides.

• Journal of Power System Engineering
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• v.6 no.3
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• pp.11-16
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• 2002

This paper describes the power performance and emission characteristics of the high speed direct injection diesel engine (2.9 litter displacements) driven by soybean oil asknown a bio diesel fuel. The results were compared to diesel fuel with blending bio diesel fuels. The soybean bio diesel fuel was added in the diesel fuel in concentration varying from 25% to 75% volume rates. We measured the emissions according to ECE 13 mode and full load, fixedengine speed. When the 25% bio diesel fuel was used, NOx emission at the ECE 13 mode test slightly decreased compared with diesel base engine. Over engine speed of 2000 rpm, the level of unburned hydrocarbon(HC) and carbon monoxide(CO) were the same to the diesel engine. Smoke emission decreased asthe blending bio diesel fuel rate increased.

• Korean Journal of Ichthyology
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• v.34 no.4
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• pp.253-261
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• 2022

After exposing Olive flounder and Korean rockfish to the concentration ranges of control (0 mg/L), 100 mg/L, 250 mg/L, 500 mg/L, and 1,000 mg/L, to investigate the physiological properties of suspended load on fish AST/GOT, ALT/GPT, ALP and cortisol were analyzed. As a result of the analysis, the AST/GOT, ALT/GPT, ALP and cortisol values were higher in the suspended load concentration section than in the control group. After artificial infection with S. parauberis for Olive flounder and V. harveyi for Korean rockfish exposed to suspended load, the survival rate was higher in the control group than in the suspended load concentration section. These results are related to the previously study results of suspended load that adversely affect fish, suggesting that suspended load affects the health of fish.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.244.1-244.1
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• 2010

Bio energy development by using Low Calorific Gas Turbine(LCGT) has been developed for New & Renewable energy source for next generation power system, low fuel and operating cost method by using the renewable energy source in landfill gas (LFG), Food Waste, water waste and Livestock biogas. Low calorific fuel purification by pretreatment system and carbon dioxide fixation by green house system are very important design target for evaluate optimum applications for bio energy. Main problems and accidents of Low Calorific Gas Turbine system was derived from bio fuel condition such as hydro sulfide concentration, siloxane level, moisture concentration and so on. Even if the quality of the bio fuel is not better than natural gas, LCGT system has the various fuel range and environmental friendly power system. The mechanical characterisitics of LCGT system is a high total efficiency (>70%), wide range of output power (30kW - 30MW class) and very clean emmission from power system (low NOx). Also, we can use co-generation system. A green house designed for four different carbon dioxide concentration from ambient air to 2000 ppm by utilizing the exhaust gas and hot water from LCGT system. We look forward to contribute the policy for Renewable Portfolio Standards(RPS) by using LCGT power system.