• Korean Journal of Microbiology
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• v.49 no.4
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• pp.343-352
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• 2013

In this study, we have evaluated the effect of efficient microorganisms on odor-removal efficiency and early stabilization of the burial sites. We have developed an efficient microorganism designated as 'KEM' which have the ability to degrade organic compounds and remove odor effectively. Other efficient microorganisms already used on site, such as EM and Bacillus sp., were also compared. We preceded these experiment using lab-scale reactors under three conditions (control, only media and only body) and comparing the effect of with or without the application of tree efficient microorganisms separately. Analysis was focused on eight components (ammonia, TMA, $H_2S$, methyl mercaptan, dimethyl sulfide, dimethyl disulfide, $CO_2$ and $CH_4$), and as a result, efficient microorganisms were shown efficiency in the removal of ammonia and methyl mercaptan. The applied KEM decayed up to 71.2% of the buried meat. We were unable to observe significant differences in microbial communities between efficient microorganisms-treated and non-treated reactors due to the large presence of microorganisms in both soil and carcasses. However, it was possible to observe the effect on odor control and decay rate through the application of efficient microorganisms.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.88-95
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• 2014

In general, odorants are added to fuel gases, such as LPG, LNG and city gas, to prevent gas poisoning, ignition, explosion, or other accident caused by fuel gases, and to enable immediate and easy detection of fuel-gas leakage by emitting an offensive smell. This study describes a study on the performance and exhaust emissions (CO, THC, $CO_2$, $NO_x$, $SO_2$) characteristics of liquefied petroleum gas (LPG) engine using LPG fuel with new sulfur free odorant (K-Petro S-Free). New sulfur free odorant (40 mg/kg) was added to 2 type LPG fuels for summer, and winter and it was used in performance and exhaust emissions, compare to LPG fuel with sulfur containing odorant (EM, ethyl mercaptan). Engine performance using LPG with sulfur free odorant was similar to LPG with sulfur-containing odorant. Exhaust emissions (CO, THC, $CO_2$, $NO_x$) of LPG with sulfur free odorant were also similar characteristics, compare with sulfur containing odorant. Especially, $SO_2$ emission using LPG with K-Petro S-Free odorant was more reduced 83 % than LPG with sulfur containing odorant(EM) at 2000 rpm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8665-8672
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• 2015

In this study, to investigate the feasibility of malodorous substance and organic matter removal by digest sludge in sewage treatment plants, ammonia, methyl mercaptan(MMC), and hydrogen sulfide($H_2S$) in a reactor submerged with BIO-CLOD(BIO-CLOD) and a reactor not submerged with BIO-CLOD(Non BIO-CLOD) were measured at 24 hours, 48 hours, and 72 hours after the submergence of BIO-CLOD. Whereas the reactor in which BIO-CLOD was submerged showed an ammonia removal rate of 48% and high $H_2S$ and MMC removal rates exceeding 98% in 24 hours, the reactor in which BIO-CLOD was not submerged showed an ammonia removal rate of 45%, an $H_2S$ removal rate of 71%, and an MMC removal rate of 84% in 24 hours indicating the possibility of removal of malodor using BIO-CLOD. A nitrification was shown in which ammonia concentrations decreased over time while nitrate nitrogen concentrations increased and sulfur based malodor components were oxidation decomposed indicating that BIO-CLOD had effects to increase sulfate concentrations in the solution and that sulfate concentration increases and atmospheric $H_2S$ removal rates were correlated with each other. With regard to decreases in organic matter in reactor effluents, BIO-CLOD did not affect in a short period of time and when reactors were operated with HRT 12 hours and HRT 24 hours, HRT 12 hours was considered desirable in terms of economy.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.174-177
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• 1993

Ultara violet ray air cleaner to use as the sterilization and deodorization device in refrigerator was designed and made of UV lamp and carbon block as the main components. The intensity of the lamp was $2.38\;mW/cm^2$ and reflector was installed to increase the radation. After running the device for 12 hours, 80% of the population of airborn bacteria was sterilized both at 48 and 480 liter refrigerator chambers. Ozone production caused by UV-ray reached 0.082 ppm at holding section within a few second when the device was operated at $25^{\circ}C$ and it showed 0.06 pm at $3^{\circ}C$. Deodorization effect was 2.5 times greater than that of a device made of electrical are principle at $25^{\circ}C$. New device 2 times more effectivly decreased trimethylamine and methyl mercaptan content applied as odor indicator substance in chamber at $3^{\circ}C$ than electrical arc type.

• The Journal of Korean Medicine
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• v.31 no.4
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• pp.151-163
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• 2010

Objective: We investigated the oral malodor inhibitory effect of Scutellariae Radix (SR), Phellodendri Cortex (PC), Moutan Cortex (MTC) and Magnoliae Cortex (MGC) for the development of a gargle solution. Methods: 1. Against P. gingivalis and Pr. intermedia, the minimal bactericidal concentration (MBC) and the change of viable cells that were exposed to 1% each herbal extract were observed. 2. Deodorizing activity of 2% herbal extract and Garglin $Mint^{(R)}$ against methyl mercaptan were evaluated by gas chromatography (GC). 3. We used the salivary sediment system (SSS) as the malodor model. 4. The clinical examination was repeated 3 times by 2 subjects by $Halimeter^{(R)}$. Baseline VSC of each subject was measured. Then, the control subject gargled with cysteine for 30 sec. After 4 min, subjects would gargle for 30 seconds with herbal extracts (2%) and Garglin $Mint^{(R)}$. Subsequently, the concentration of VSC was measured at 0, 4, 8, 12, 16, 20, 40 and 60 minutes. Results: 1. Against P. gingivalis, MBC of SR, PC and MTC was 0.1%, and MBC of MGC was 1%. Removal time of P. gingivalis was as follows; 5 hr in MGC, 24 hr in SR and PC, and 48 hr in MTC. Against Pr. intermedia, MBC of SR and PC was 0.5%, and MBC of MTC, MGC was 1%. Removal time of Pr. intermedia was as follows; 5 hr in MTC and 24 hr in SR, PC and MGC. 2. Deodorizing effect of herbal extracts against methyl mercaptan was as follows; MGC and MTC had 100%, SR had 82.22%, PC had 66.60%, Garglin $Mint^{(R)}$ had 40.54%. 3. In the experiment using SSS, PC and MTC had statistically significant malodor-inhibitory effects (p<.05). 4. In the clinical examination, PC and MGC had statistically significant inhibitory effects at every elapsed time compared to the control subject. MTC had that until 40 min. SR had that at 0, 4, 8, 20, and 60 min. Conclusions: SR, PC, MTC and MGC have an antibacterial effect and the chemical removable activity of the oral malodor caused by VSC. These four herbs could have potential as effective anti-malodor agents.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.2
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• pp.71-82
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• 2006

This study was carried out to assess and analyze the overall problems of the facilities in recycling and treating of foodwaste on the basis of the unit operation facilities. It proposes effective alternatives for the high profitable management that can meet the regulation of the facilities. The study is composed of several parts including a collection of academic reports, field studies regarding the facilities operated by local government and the private sector, the analysis on odor samples from compost facilities and processing facilities for animal feed from foodwaste. Twenty facilities were surveyed on the field to find out the existing problems and to compare between facilities. Several facilities didn't meet the governmental regulation on some processes, especially the stages of input, storage, odor control and the qualities of final products under the unit equipment operation. The analysis on the odors from the phases of input, shredding and fermentation of a compost facility and processing facilities for feed, the odors from shredding equipments were higher in concentration than the others. The Major odors from the composting facility contained hydrogen sulfide ($H_2S$), methyl mercaptan ($CH_3{SH}$), Dimethyl sulfide ($(CH_3)_2S$) and Ammonia ($NH_3$) and the major odors from the animal feed facility contained methyl mercaptan ($CH_3{SH}$), Trimethylamine ($(CH_3)_3N$) and Acetaldehyde ($CH_3CHO$).

• Analytical Science and Technology
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• v.15 no.1
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• pp.80-86
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• 2002

The simultaneous analysis of the odorous compounds designated by law in Korea and Japan was examined with the thermal desorber gas chromatography-mass spectrometry using one column. The approximate concentrations of trimethyl amine, acetaldehyde, methyl mercaptan and dimethyl sulfide were estimated. Styrene, dimethyl disulfide, propionaldehyde, n-butyl aldehyde, i-butyl aldehyde, n-valeraldehyde, i-valeraldehyde, ethyl acetate, toluene, xylene, methyl i-butyl ketone and i-butanol were detected at concentrations of the detection limits of their threshold values. As a typical example of simultaneous analysis of the odorous compounds, the volatile organic compounds emitted from compost procedure of food waste were concentrated and analyzed with thermal desorber/GC/MSD, and major malodorous compounds were estimated from the concentrations and threshold values of the detected components. From the result of analysis, 34 compounds were confirmed and among them, trimethyl amine, i-valeraldehyde, methyl mercaptan, methyl allyl sulfide, dimethyl sulfide, acetaldehyde, ethanol, n-butyaldehyde were expected to attribute to the odor in order of strength.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.123-128
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• 2004

Effects of jeotkal (salted-fermented seafoods) addition on acid production, growth of lactic acid bacteria, sensory properties, and volatile odor components of kimchi were investigated. Changes in pH and acidity of kimchi added with myulchi-aekjeot, kanari-aekjeot, and aekche-Jukjeot were similar to, whereas those of saeu-jeot sample on 0, 2, and 4 days of ripening were slightly different, those of control sample. Changes in pH and acidity of jogae-jeot sample during whole ripening period were markedly different from those of other samples. Numbers of lactic acid bacteria of all samples on 0 and 4 days were $1.8-2.6{\times}10^{5}\;and\;1.0-2.5{\times}10^{9}\;CFU/mL$, respectively. Overall acceptability and taste of kimchi added with jeotkal except jogae-jeot were higher than those of control sample, with saeu-jeot-added kimchi showing the highest scores. Eight volatile odor components were identified in 6-day-ripened kimchi samples, and those of saeu-jeot sample were slightly higher than those of other samples. Diallyl sulfide and methyl propyl disulfide were produced in 6-day-ripened samples. Ethanol, methyl allyl sulfide, and dimethyl disulfide concentrations increased, whereas that of allyl mercaptan decreased in 6-day-ripened samples compared to unripened ones.

• Microbiology and Biotechnology Letters
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• v.45 no.3
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• pp.257-264
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• 2017

Mixed substrate oil cakes are known to emit sulfides, ammonia, and amines. Microorganisms capable of removing odorous gases related to these sulfur compounds were isolated from colonies enriched in vials containing oil cakes and water. Activity tests for hydrogen sulfide and methyl mercaptan reduction were performed to measure the sulfide reduction ratio of the isolates. Control groups were prepared with 0.25 g oil cakes and 10 ml water in a 100-ml vial without inoculation. The experimental groups were prepared similarly, albeit with an inoculum. Hydrogen sulfide removal efficiency of >90% was observed for an isolate, which was identified as Brevundimonas diminuta by 16S rDNA sequence analysis. The sequence was deposited in the Korean Collection for Type Cultures under the accession number KCTC11724BP. B. diminuta could remove up to 200 ppmv standard hydrogen sulfide in 24 hours and demonstrated a maximum hydrogen sulfide and methyl mercaptan removal efficiency of 100% at 453 ppmv and 98 ppmv, respectively, in vial tests. Furthermore, B. diminuta cells in 20% (v/w) medium showed removal efficiency of >85% for sulfur compounds in an odor emission chamber for swine manure.

• Korean Journal of Veterinary Research
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• v.58 no.2
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• pp.87-94
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• 2018

This study assessed the effects of Weissella cibaria (W. cibaria) CMU on oral health in male and female beagles (n = 18) by measuring oral malodor and periodontal disease-related parameters (calculus, plaque, and gingivitis indices). Oral malodor and indicators of periodontal disease were assessed in five treatment groups: negative control (scaling and 0.24 mg of maltodextrin, n = 3), positive control (0.24 mg of maltodextrin, n = 3), and W. cibaria CMU groups (each n = 4) at low (CMU-L, $2{\times}10^7$ colony forming unit [CFU]), medium (CMU-M, $2{\times}10^8CFU$), and high (CMU-H, $2{\times}10^9CFU$) concentrations. After feeding with W. cibaria CMU for 6 weeks, total volatile sulfur compound concentrations in the CMU-L ($2.0{\pm}1.04ng/10mL$), CMU-M ($2.4{\pm}1.05ng/10mL$), and CMU-H ($2.6{\pm}1.33ng/10mL$) groups were significantly lower than in the positive control group ($3.2{\pm}1.65ng/10mL$). Also, CMU-L ($1.4{\pm}0.83ng/10mL$) and CMU-H ($1.9{\pm}1.14ng/10mL$) groups had methyl mercaptan levels lower than that in the positive control group ($2.4{\pm}1.21ng/10mL$) at week 2. The plaque index was significantly lower in the CMU-H group ($4.5{\pm}0.28$) than in the positive control group ($5.9{\pm}1.08$) at week 6. W. cibaria CMU could be useful as a novel oral hygiene probiotics for reducing volatile sulfur compounds production and inhibiting plaque growth in companion animals.