• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.514-519
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• 1990

Some chemical constituents were monitored to evaluate the biochemical and nutritional aspects of ${\gamma}-irradiated$ mushrooms associated with shelf-life extension. Volatile components identified by GC and GC-MS were composed primarily of 1-octen-3-ol(68%)). benzaldehyde(13%), 3-octanone(8%), benzyl alcohol(5%), 3-octanol(2%)). 1-octen-3one(1%). etc. Treatment with 2kGy-irradiation and subsequent storage for 17 days at $(9{\pm}1^{\circ}C\;and\;80{\pm}7%$ RH resulted in appreciable changes In their contents. even though negligible changes were observed in GC patterns between the nonirradiated and 2 kGy-irradiated samples. Most of the amino acids were resistant to ionizing energy of 2 kGy, while sulfur-containing free amino acids were affected significantly by ${\gamma}-irradiation$.

• Food preservation and processing industry
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• v.7 no.1
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• pp.33-44
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• 2008

마늘의 저장 중 생리활성과 향미에 중요한 영향을 미치는 성분의 변화를 발표된 논문을 중심으로 정리하여 살펴보았다. 또한 마늘의 냄새를 최소화하고 생리활성을 극대화할 수 있는 기능성식품의 소재개발 타당성을 살펴보기 위하여 열처리(blanching)로 마늘 중의 효소를 모두 불활성화 시킨 후, 이에 마늘로부터 추출한 alliinase를 가하여 반응조건에 따른 alk(en)yl thiosulfinates 생성 및 이들의 분해산물인 휘발성 황함유화합물의 함량변화를 측정하였다. 수확한 마늘의 최종 저장물질로 알려진 -glutamyl-S-alk(en)yl-L-cysteines는 마늘중에 존재하는 -glutamyl-transpeptidase 및 oxidase의 작용에 의하여 감소한 반면 S-alk(en)yl cysteine sulfoxide는 감소한 만큼 증가하였으며, 이는 $-3^{\circ}C$ 및 실온($23^{\circ}C$)에서 보다도 냉장온도($4^{\circ}C$)에서 가장 많이 변화하는 것으로 나타났다. 이러한 감소 및 증가현상은 -glutamyl-S-(2-popenyl)-L-cysteine이 -glutamyl-S-(trans-1-propenyl)-L- cysteine이나 -glutamyl-S-methyl-L-cysteine보다 더 컸다. -glutamyl-S-(2-propen yl)-L-cysteine은 $4^{\circ}C$에서 저장 60일 만에 66%가 감소한 반면 이로부터 생성된 S-(2- popenyl)-L-cysteine sulfoxide는 그 만큼 증가하였다. -glutamyl-S-(trans-1-propenyl)-L-cysteine 및 -glutamyl-S-methyl-L-cysteine도 $4^{\circ}C$에서 150일간 저장한 경우 각각 81% 및 39%가 감소하고, 이들로부터 각각 생성된 S-(trans-1- propenyl)-L-cysteine sulfoxides 및 S-methyl-L-cysteine sulfoxide는 증가하였다. 한편 열처리 마늘에 alliinase를 가하여 함황화합물을 재생성 시킨 결과 8종의 S-alk(en)yl cysteine sulfoxides를 확인할 수 있었다. S-(2-propenyl)-L-cysteine sulfoxide은 전체 thiosulfinates함량의 약 60%를 차지하는 것으로 나타났다. 100, 200, 300 및 400 unit의 alliinase를 첨가하여 15분간 반응시킨 결과 총 thiosulfinates는 생마늘(대조구)에 비하여 각각 37, 68, 77 및 80%가 생성되는 것으로 나타났다. GC/MSD를 이용하여 대조구 및 효소를 첨가하여 반응시킨 시료의 휘발성 향기성분을 분석한 결과 alliinase를 100, 200, 300 및 400 unit 첨가하여 15분간 반응시키면 각각 마늘의 휘발성 향기성분이 25, 36, 66및 76% 씩 재 생성되는 것으로 나타났다. 이상의 결과를 종합해 볼 때 마늘을 이용한 제품개발이나 연구를 할 경우 마늘의 저장조건에 따른 생리활성물질의 분석결과를 근거로 하여 이루어져야 하며, 또한 효소를 이용하여 적절히 반응시키면 마늘 냄새를 $30{\sim}80%$ 범위 내에서 조절이 가능한 것으로 나타났다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.358-359
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• 2003

산업화가 급속히 진행됨에 따라 삶의 질은 향상된 반면, 대기오염으로 인한 피해는 증가하고 있다. 대기 중 존재하는 휘발성 유기화합물 (VOCs)은 인체에 독성을 가지며 암을 유발하고, 오존의 전구물질(precursor), 광화학 스모그의 원인물질, 성층권의 오존층 파괴 및 지구온난화에도 영향을 미칠 뿐 아니라 (Derwent et al., 1996) 악취를 유발하기도 한다. 악취는 황화수소(hydrogen sulfide), 메르캅탄류(mercaptans), 아민류(amines) 등 기타 자극성 있는 기체상 물질이 사람의 후각을 자극하여 불쾌감과 혐오감을 주는 냄새로 정의되며, 주로 인체의 위해성보다는 정신적ㆍ심리적인 피해를 일으키는 감각공해라고 할 수 있다 (환경부, 2002). (중략)

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.116-122
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• 1977

The volatile flavor components of Kimchis were identified and the volatiles of fermented Kimchis (1.29% NaCl and 4.89 NaCl) were compared with those of raw Kimchi (1.29% NaCl). After the existence of carbonyls and sulfur compounds were confirmed by precipitation method, vacuum distillation was carried out to collect the volatiles of Kimchis in traps submerged in ice+salt, dryice-acetone and liquid N, respectively. The volatile flavor components were identified by GLC. The results were; 1. 17 volatile flavor components of Kimchis were identified by comparison of retention time with those of known compounds and acetaldehyde, acetone, ethanol, ethyl sulfide were positively identified by m.p., IR, UV, TLC. etc. 2. Ethanol was the most abundant volatiles of Kimchis and the content was much higher in fermented low salt Kimchi than in unfermented low salt Kimchi. 3. On the contrary, acetaldehyde and volatile sulfur compounds were reduced in fermented Kimchis, especially in fermented low salt Kimchi.

• Journal of Periodontal and Implant Science
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• v.37 no.1
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• pp.1-10
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• 2007

연구 목적 : 구취의 주된 화학적 요소는 휘발성 황 화합물 (VSCs)들이다. 이들은 치태, 설태, 타액과 혈액, 상피세포의 혐기성 그람 음성 세균에 의한 단백분해 변성으로 만들어 진다. 또한 구취는 치주질환과 타액내의 세균의 증가를 야기하는 불량한 구강 위생상태에서 기인한다고 보고되고 있다. 이 연구의 목적은 VSCs를 측정함으로 구취에 대한 비외과적 치주 치료의 영향을 평가하고, 타액내의 세균 수를 측정함으로써 VSCs와의 상관관계를 살펴보고자 하는 것이다. 연구 대상 및 방법 : 중등도의 만성치주염을 가지는 23명의 참가자들이 대조군과 실험군으로 분류되었다. 대조군은 구강위생교육 (치간청결기구와 혀세정 포함)만을 시행하였고 실험군은 구강위생교육과 함께 24시간 내에 전악 치석제거술과 치근활택술을 시행하였다. 치료 전과 치료 4주 후에 VSCs 농도를 $Halimeter^{(R)}$(Interscan Corp., CA, USA)를 사용하여 측정하였고 타액 시료는 혐기성과 호기성 조건에서 배양되었다. 결과 : 4주 후에 두 군 모두에서 휘발성 황화합물의 농도가 유의하게 감소하였고, 실험군에서의 감소량이 통계적으로 유의하게 더 크게 나타났다. 타액 내 세균의 배양에서 총세균수에 대한 혐기성 세균의 비율이 실험군에서만 통계적으로 유의하게 감소하였다. 그러나 세균의 비율과 휘발성 황화합물의 농도와의 상관관계는 낮게 나타났다. 즉 구취의 감소는 타액 요인 보다는 치주치료에 의한 다른 복합적인 인자의 작용에 의한 것으로 추론할 수 있었다. 결론 : 본 연구는 중등도의 치주염환자에서 구강위생교육만으로도 구취의 주요 화학적 요인인 휘발성 황화합물의 농도를 감소시킬 수 있으나 비외과적 치주치료를 동반하였을 때 더욱 큰 효과를 얻을 수 있는 것으로 해석된다. 그러나 실험 참가자의 수가 적었고 장기간의 분석이 이루어지지 않았으므로 앞으로 더 많은 연구가 구취에 대한 치주치료의 영향을 이해하기 위해서 필요할 것으로 사료된다.

• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.126-133
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• 2022

The objective of this study was to analyze volatile and aroma-active compounds in Korean wild chive (Allium monanthum Maxim.) cultivated in open-fields or greenhouse systems using solvent-assisted flavor evaporation-gas chromatography (GC)-mass spectrometry and GC-olfactometry. Aroma-active compounds were evaluated using aroma extract dilution analysis (AEDA). Twenty-two aroma-active compounds with log₂ flavor dilutions (FD) of 1-10 were detected in Korean wild chive, which was cultivated in an open-field or a greenhouse. 2-Isopropyl-3-methoxypyrazine ("earthy"), 2-sec-butyl-3-methoxypyrazine ("earthy", "musty"), and dipropyl disulfide ("sulfurous") were the most predominant aroma-active compounds with log₂FD of 9-10; this was followed by dimethyl trisulfide ("onion-like") and (E)-1-propenyl propyl disulfide ("fresh onion-like"). The "sulfurous", "earthy", "pungent", and "cabbage-like" aroma notes were strong in Korean wild chive. More intense "pungent" odors were detected in Korean wild chive cultivated in an open-field, whereas more intense "cabbage-like" odors were detected in Korean wild chive cultivated in a greenhouse.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.2
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• pp.187-193
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• 2008

Biological removal capacities for volatile organic compounds (VOCs) were determined using a yeast strain, Candida tropicalis. In this study, VOCs including toluene, benzene, p-xylene, and styrene as single substrates or mixtures were tested in the batch culture of the yeast strain. In addition, a kinetic model was applied to evaluate substrate interactions between the VOCs. The yeast strain was able to biodegrade each VOC effectively as a growth substrate, implying it could applied to wide range of VOCs. When the yeast strain was subjected to VOCs in mixtures, the biodegradation rate of one substrate were either increased (stimulated) or decreased (inhibited) by the presence of the others. Both benzene and toluene were inhibited by the other VOCs, and substrate interaction parameters estimated in the model indicated that styrene was the strongest inhibitor for the benzene and toluene biodegradation. Meanwhile, the biodegradation of p-xylene and styrene was stimulated by the presence of either benzene or toluene. The biodegradation rate of p-xylene was significantly increased especially by the presence of toluene, and the styrene biodegradation was enhanced greatly by the benzene addition. The results of the substrate interaction by the yeast strain suggest that the biodegradation rates for the VOCs in mixtures should be carefully evaluated. Furthermore, the competitive inhibition coefficient could be applied as a useful index to determine the substrate interaction

• Journal of Korean Society of Environmental Engineers
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• v.29 no.6
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• pp.678-683
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• 2007

We isolated a toluene-degrading bacterium, TDB-4, from a bioreactor which designed to remove volatile organic compounds (VOCs) from the contaminated air. Based on the results of 16S rRNA gene analysis, it was classified as Pseudomonas sp. The toluene degradability was estimated in the variable toluene and bacterial concentrations. The bacterial growth and degradation rate was higher in the samples supplied with 50 ${\mu}mole/vial$ of toluene than with 10 ${\mu}mole/vial$. It was decreased, however, in the samples with 100 ${\mu}mole/vial$, indicating that toluene inhibit the growth or degradation activity of TDB-4 at high concentration. When the degradation ability of other compounds was examined, TDB-4 can degrade other VOCs such as styrene, benzene, and xylene. These results will be helpful to optimize the operating conditions to improve the efficiency of a bioreactor in detoxification of VOCs.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.8
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• pp.603-610
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• 2009

This research was performed to improve removal efficiency of toluene and methyl ethyl ketone (MEK) using Candida tropicalis, one of the yeast species. An airlift loop bioreactor (ALB) was employed to enhance the capability of mass transfer for toluene and MEK from the gas phase to the liquid, microbial phase. Polymer gel media made from PAC, alginate and PEG was applied for the effective immobilization of the yeast strain on the polymer gel media. The experimental results indicated that the mass transfer coefficient of toluene without polymer gel media was 1.29 $min^{-1}$ at a gas retention time of 15 sec, whereas the KLa value for toluene was increased to 4.07 $min^{-1}$ by adding the media, confirming the enhanced mass transfer of volatile organic compounds between the gas and liquid phases. The removal efficiency of toluene and MEK by using yeast-immobilized polymer gel media in the ALB was greater than 80% at different pollutant loading rates (5, 10, 19 and 37 g/$m^3$/hr for toluene, 4.5, 8.9, 17.8 and 35.1 g/$m^3$/hr for MEK). In addition, an elimination capacity test conducted by changing inlet loading rates stepwise demonstrated that maximum elimination capacities for toluene and MEK were 70.4 and 56.4 g/$m^3$/hr, respectively.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.814-821
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• 1996

An attempt was made to determine the effects of drying methods including shady air drying, presteamed and shady air drying, microwave drying, and freeze drying on the volatile flavor components of Capsella bursapastoris. Essential oils from the samples were isolated by Simultaneous steam distillation-extraction (SDE) method using diethyl ether as solvent. Concentrated samples were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS). Respective 30, 18, 29, and 26 volatile flavor components were identified in shady air dried samples, presteamed and shady air dried samples, microwave dried samples, and freeze dried samples. The kinds and amounts of volatile flavor components evidently depended upon the drying methods. Trimethyl sulfide was regarded as the most abundant component in shady air dried samples, dimethyl trisulfide in presteamed and shady air dried samples, and phytol in microwave or freeze dried samples.