In South Korea, increase in kimchi import from China has emphasized the importance of noticing the origin of production area, largely because of the price and safety concerns. Nevertheless, identification of it depends on a complex physicochemical method. Hence, the objective of this study is to develop a statistical algorithm applicable for analyzing volatile compounds measured by electronic nose so that the device can be used for simple classification of kimchi by its production origin. Discriminant function analysis (DFA), one of multi-variate analysis, was mainly used for analyzing big-size data of volatile compounds detected from kimchi produced either in South Korea or China. Result showed that DFA could completely separate 69 varieties of kimchi by its origin of production (39 from South Korea and 30 from China). This result suggests that volatile compounds can be an index for identifying origin of kimchi and consequently, electronic nose is an optimal option for identifying origin of kimchi production when combined with multi-variate statistics.

This study was conducted to investigate changes in organoleptic properties and taste components including free sugar, organic acid and free amino acid with addition of walnut. Changes in total nitrogen were insignificantly different with addition of walnut. Amino type nitrogen content was decreased in proportion to supplemental level of walnut. Content of organic acids, of which three kinds were detected, such as citric acid, malic acid and lactic acid increased more than two times with addition of walnut. Contents of free sugar and amino acid were decreased with addition of walnut. The proportion of essential amino acid was 40.6~41.4 percent. Glutamic acid in total amino acid was increased in proportion with addition of walnut. The highest sensory evaluation score was recorded in soy sauce with addition of 2 percent walnut. Together, it was expected that 2 percent addition of walnut to soy sauce has a positive effect on the taste of soy sauce.

Streptomyces species have been studied to find potent pest control agents as an alternatives to chemical insecticides.Previously, one of the ethyl acetate extract of Streptomyces isolates cultured on unpolished rice medium showed highlevel of juvenile hormone antagonist and larvicidal activities against pest insects including Aedes albopictus, Plutella xylostellaand Laodelphax striatellus. It has been known that the biosynthesis of secondary metabolites of Streptomyces could beinfluenced by a variety environments such as nutritional composition and growth conditions. In this study, to optimizeculture conditions for stable production of insecticidal compounds from this isolate, binding assay and bioassay-guidedmonitoring were conducted using various culture conditions.

The aim of this study was to examine indoor fungal concentration and fungal volatile organic compounds(VOCs) in single-person households. A total of 22 houses occupied by one person were investigated in this study. 19 VOCs detected in the field were estimated as fungi-derived VOCs through a review of the literature, and 11 VOCs were confirmed as fungal VOCs by laboratory experiments. Exposure to fungal VOCs in the indoor environment has been confirmed to be highly influenced by airborne fungal concentration and indoor humidity. 3-octanone was characterized by a clear generation profile in Aspergilus versiocolor, and n-decane in Pencillum chrysogenum. ntetradecane emitted by Stachybotrys chartarum exhibited a tendency to occur consistently. The observations made in this study demonstrated that single-person households can easily be exposed to fungi, and MVOCs can be used as an indicator of fungal exposure in indoor environments.

In this work, the effects of hydrogen reduction on the microstructure and thermoelectric properties of (GeTe)0.85(AgSbTe2)0.15 (TAGS-85) were studied by a combination of gas atomization and spark plasma sintering. The crystal structure and microstructure of TAGS-85 were characterized by X-ray diffraction(XRD) and scanning electron microscopy (SEM). The oxygen content of both powders and bulk samples were found to decrease with increasing reduction temperature. The grain size gradually increased with increasing reduction temperature due to adhesion of fine grains in a temperature range of 350 to 450 °C. The electrical resistivity was found to increase with reduction temperature due to a decrease in carrier concentration. The Seebeck coefficient decreased with increasing reduction temperature and was in good agreement with the carrier concentration and carrier mobility. The maximum power factor, 3.3 × 10−3 W/mK2, was measured for the non-reduction bulk TAGS-85 at 450 °C.

식품용 금속 캔의 내면 코팅에 사용되는 에폭시 수지로 부터 용출되어 식품으로 이행될 수 있는 BPA, phenol, ptert- butylphenol과 BADGE, BFDGE 및 그 가수분해산물과 염화물 등 총 9종의 비스페놀 관련물질들을 HPLC/FLD 를 사용하여 동시 분석하는 방법을 확립하여 검량선 및 회 수율을 검토하고 식품유사용매로의 이행량을 조사하였다. 23종류의 식품용 금속 캔 총 161건을 대상으로 60oC에서 30분간 용출한 결과물, 4% 초산, 50% 에탄올 및 n-heptane 에서 전부 불검출이었다. 95oC에서 30분간 용출한 결과는 식품유사용매로 4% 초산과 50% 에탄올을 사용한 경우 BPA는 불검출~10.77 μg/L, phenol은 불검출~2.35 μg/L 검출되어 정량한계 수준이었으며, 국내 용출규격인 600 μg/ L에 비해 매우 낮은 수준임을 확인하였다. 또한 금속 캔은 저장성이 우수하여 식품을 장기간 보관하는 특징이 있어 보관기간(0~90일) 및 온도조건(4, 25, 60oC)에 따른 BPA 등 9개의 BPA 관련물질들의 이행량의 변화를 측정하였다. 온도조건이 4oC 및 25oC인 경우 90일 동안 모든 식품유 사용매에서 BPA를 비롯하여 9종의 BPA 관련물질들은 검 출되지 않았다. 식품유사용매로 물과 4% 초산을 사용하여 60oC의 온도에서 90일간 저장한 경우 BPA와 BADGE·2H2O 는 시간이 지남에 따라 약하게 증가하는 경향을 보였으나, 이행량이 70일 이후부터 급격한 증가 없이 대체로 유지되는 수준이었고, 검출값 또한 정량한계 수준으로 매우 낮 게 나타났다. 따라서 식품용 금속 캔으로부터 BPA를 비롯한 관련 물질들의 이행량은 안전한 수준으로 관리되고 있음을 알 수 있었다.

The physicochemical properties of dry wine produced from domestic kiwifruit according to production year from 2008 to 2012 were studied. pHs of wine were from 4.02(F wine, production year 2009, sterilized) to 4.11(D wine, production year 2012, non-sterilized) and their acidities were lowest in D wine(0.79%) and highest in F wine(1.18%). All the wines have the same soluble solids of 8 °brix and 12% of alcohol, respectively. The reducing sugar was lowest in A wine(production year 2008, non-sterilized) and highest in D wine. The lactic acid was detected as a main organic acid and the free sugar was detected only fructose. As main flavor components, ethyl acetate and 1-pentanol were detected and their sum of 80~90% and a small amount of phenylethyl alcohol which providing rose-like aroma was also detected. The contents of soluble phenolics were highest in D wine(1.07 g/L) and lowest in C wine(0.80 g/L), corresponding to the antioxidant activity was highest found in D wine according to their soluble phenolic contents.

The objectives of this study were to select the seeds of Cucurbitaceae and Solanaceae genotypes in terms of superior with bioactive compounds content and to inform sophisticated data for developing the high value-added products. We evaluated to aspects of the antioxidant activity, polyphenol content, and flavonoid contents in seeds from two vegetable family. We used in the Cucurbitaceae(watermelon, squash, bitter gourd, and sponge gourd) and Solanaceae(hot pepper, sweet pepper, and egg plant) the total 408 genotypes. In Cucurbitaceae, polyphenol content of watermelon and squash genotypes were ranged 19.9-343.8 and 6.1-81.2 mg·100 g-1 DW, respectively. The polyphenol content of watermelon genotypes was 12% among all genotypes over 160 mg·100 g-1 DW. The mean of flavonoid content in watermelon and squash genotypes represented 80 and 41.3 mg·100 g-1 DW, respectively. In Solanaceae, flavonoid content of hot pepper genotypes was ranged 64.4-472.5 mg·100 g-1 DW, with an average of 165.0 mg·100 g-1. The 23 hot pepper genotypes were classified over 90% antioxidant activity. The antioxidant activity of sweet pepper was ranged 35.9-90.3%, and 23% of all genotypes represented 82% antioxidant activity. The polyphenol and flavonoid content of egg plant was ranged 38.1-642.0 mg·100 g-1 DW and 14.2-1217.0 mg·100 g-1 DW, respectively. In addition, we selected that 8 egg plant with the superior genotypes for antioxidant activity, polyphenol, and flavonoid content. Results revealed that there was significant variation of antioxidant activity and bioactive compounds contents in both vegetable famaily. In addition, we suggested that selected genotypes seeds with high contain bioactive compounds will be more efficiency to develop natural value-added products.

Plant essential oils have been reported to show repellent, insecticidal and growth-reducing effect on many insect herbivores. Recently, it has been reported that plants synthesize secondary metabolites regulating insect juvenile hormone (JH) receptor complex as a part of their defense mechanisms. We tested 180 plant essential oil compounds using a yeast two-hybrid system transformed with the Aedes aegypti JH receptor as a reporter system. Among them, we identified 17 compounds that showing high JH agonist (JHA) or antagonist (JHAN) activities. They were grouped into 4 groups by their structural similarity and their insecticidal activity was tested against larvae of Aedes albopictus, Plutella xylostella, Plodia interpunctella and Laodelphax striatellus. These results could provide insights on the plant-insect coevolution and may be useful for the development of insect specific and safe pesticides.

Insect growth regulators (IGRs) are insecticides that disrupt the normal development of target insects by inducing symptoms such as premature molting or supernumerary larval stages. Juvenile hormone (JH)-based IGRs are of particular interest because they simulate or interfere with the formation of juvenile hormone receptor complex. Insect larvae generally have been poorly susceptible to JH agonists (JHAs) because endogenous JH titer is already high in the larval stage. In contrast, JH antagonists (JHANs) might be more effective for control of target pests in larval stages through interference in the status quo action of JHs. In this study, we tested 2,354 chemical compounds using the yeast-two hybrid system to identify JHANs. Among them, K265674 sample was selected and its insecticidal activity was evaluated against Aedes albopictus larvae. These results may be useful for development of novel IGR insecticide.

Insect infestation leads to huge loss of agricultural products and transmission of vector-borne diseases causing millions of deaths per annum. Juvenile hormone (JH) controls the development and reproduction of insects, therefore the grouth of insects can be inhibited by interfering the action of JH. Based on this, we developed a novel insect species-specific screening system to identify juvenile hormone antagonists (JHANs) from natural origin. These compounds can disrupt JH-mediated insect development by interfering the binding of a heterodimer, steroid receptor coactivator (SRC), with its partner protein, the methoprene-tolerant (Met) JH receptor. This screening system could be used as a new tool to develop eco-friendly and species-specific insecticides.

There has been growing concern over the emissions of formaldehyde and VOCs from automotive interior materials, as these could have an important impact on the in-vehicle air quality (IVAQ) of automotive vehicles. Odor along with VOCs refers to the automotive interior smell emitted directly or indirectly from any part of an automotive interior, based on human olfactory senses and a comfort evaluation of vehicle quality. The objective of this paper is to compare the odor intensity using GC/MS analysis method and odor sensory test in accordance with ISO 12219-2. For the compounds having low odor threshold value and high VOC concentration, it was found that there was the same tendency in each field of odor whether the instrument analysis method or the odor sensory test method was used.

This study investigated the chemical composition of Petasites japonicus (S. et Z.) Maxim essential oil. During the period 2011~2013, P. japonicus (S. et Z.) Maxim plant was investigated for composition of the essential oil. Chemical composition and characteristic compounds of the essential oils from the aerial parts of the plant according to the crop year studied. The essential oils consisted of sesquiterpene compounds, which were the most abundant components. Samples collected in 2011 were found to be richer in oxygenated sesquiterpenes, while samples collected in 2012 and 2013 were richer in diterpene alcohols and sesquiterpene hydrocarbons, respectively. Ninety-two compounds were identified in the P. japonicus (S. et Z.) Maxim essential oil of 2011, and caryophyllene oxide (20.49%), β-caryophyllene (10.28%), β-bisabolene (6.80%), and alloaromadendrene (6.50%) were the major compounds. Seventy-four compounds were identified in the plant essential oil of 2012, and phytol (17.22%), α-farnesene (15.31%), α-caryophyllene (9.93%), and β-caryophyllene (6.12%) were the major compounds. Ninety-two compounds were identified in the plant essential oil of 2013, and α-farnesene (22.42%), α- caryophyllene (21.49%), pentadecane (15.35%), and germacrene (5.70%) were the major compounds. The content of most of the chemical constituents varied significantly with different harvesting time. The content of α-caryophyllene and caryophyllene oxide was increased significantly from 2011 to 2013. The content of α-caryophyllene and isocaryophyllene was decreased significantly from 2011 to 2013.

살모넬라증은 가축에 심각한 피해를 유발하는 질병으로, 축산업과 식품산업에 많은 경제적 손실을 초래하고 있다. 본 연구에서는, 복합 인산염을 주성분으로 하는 분말 소독제의 Salmonella Typhimuriums에 대한 살균효과 시험을 수행하였다. 배지희석법을 이용한 살균효력시험은 4℃에서 30분 동안 시험 세균을 희석 소독제에 노출시켜 소독제의 가장 효과적인 낮은 희석배수를 결정하는 시험이다. 본 분말 소독제와 시험 세균을 처리조건에 따라 경수와 유기물로 희석하여 반응을 시켰다. 유기물 조건에서, Salmonella Typhimurium에 대한 소독제의 살균력은 경수조건에서의 살균력과 비교하여 낮게 나타났는데, 이는 유기물들에 의한 소독제의 살균 유효성분에 대한 저해작용에 따른 것으로 사료된다. 분말 소독제는 Salmonella Typhimurium과 같은 병원체에 대해 살균효과를 가지므로, 살모넬라증과 같은 세균성 질병의 확산을 제어하는데 효과적으로 이용될 수 있을 것으로 사료된다.

Per capita nail-products use and airborne VOCs emission in four techniques of nail care (full coat coloring, UVgel polish, repair silk, and acrylic overlay) are estimated in this study. These assessments were carried out in a sealed test chamber using artificial hand and nails. A polish remover and a gel cleanser as cleanser and acrylic liquid as solvent were the most commonly used nail products in all 4 of the nail care techniques. Acetone, isopropyl alcohol, and methanol, which are major components of a polish remover, were commonly detected in all nail care techniques while acetone was detected the most. In addition to these airborne VOCs, a variety of other components such as ethyl acetate, cyclohexane, and toluene were identified in full coat coloring technique. In the process of UV-gel polish care technique, the main airborne VOCs were caused by solvents and were not involved in the curing process of UV gels (base gel and top gel) and gel bonder. In the case of repair silk nail care techniques, which generated the most VOCs, the total amount of VOCs detected was about 1,118.8 ± 359.6 mg/capita. Of the VOCs, butane (862.2 ± 283.9 mg/capita), which is contained in glue dryer, represented the largest share. In the process of acrylic overlay nail care technique, ethyl methacrylate (EMA), which is the basic element of acrylic, and highly toxic methyl methacrylate (MMA) were detected at 396.6 ± 42.3 mg/capita and 141.8 ± 8.2 mg/capita, respectively. The per capita data is very useful in designing a ventilation system for environmental improvement of a nail shop and setting a health care policy for nail artists and customers.

This study compared the stability of odor compounds in three different types of polymer sampling bags. Tedlar, PET (polyethylene terephthalate) and aluminized polyester bag were used. A sample was collected from the interior of a new automobile which was parked in an outdoor parking lot. It was found that the Tedlar bag showed lower stability for odor active compounds than the PET bag. Meanwhile, the PET bag had good stability for odor compounds compared to the aluminized polyester bag. The PET bag showed a stability for the molecules smaller than toluene that was comparable to the canister, but showed a lower recovery for molecules bigger than C7. The FID signal of the sample in the PET bag was reduced by 1.7times after 3days storage compared to 24 h storage. The number of detected odor active compounds was reduced by half, and odor intensity was also decreased by 2~3 degrees. Considering the factors of repeated use, usability and price, a PET bag covered with a black plastic bag was the most appropriate approach for odor sampling in an automobile interior.

The consumer products in the living environments include a variety of chemicals which could be harmful in the human health. The aim of this study was to assess the inhalation exposure and risk for cleaning workers who had used bleach in the university. A total of 81 cleaning workers took part in this study. Frequency and amount of cleaning bleach during working hours were investigated by questionnaire interviews. Exposure assessment was used by the exposure algorithm and exposure factors. Used cleaning bleaches were analyzed to identify the ingredients, and risk by exposure was assessed by separating as carcinogen and non-carcinogen substances. The results of chemical substances and the questionnaire were used to assess the exposure factors, and the inhalation doses were calculated through inhalation exposure algorithm. According to the questionnaires for the cleaning workers, frequence of cleaning bleach was 11.66 ± 7.21 times per month. And average usage time and amount per cleaning work were 30.78 ± 36.00 minute and 20099.53 ± 12998.60 mg, respectively. Risks for carcinogenic substances of formaldehyde, ethylbenzene, and chloroform were exceeded by 56.79%, 27.16%, and 82.72% as the reference value of 10−6, respectively.

The objective of this experiment was to evaluate the effect of Chamaecyparis obtus extract to reduce odor emissions released from the swine feeding operations. Finisher pigs [Landrace × (Yorkshire × Duroc)] with an initial body weight averaging 50 kg were housed separately in two rooms with eighty eight pigs in each room at a swine feeding operation site. C. obtus extract was sprayed in the room by ceiling sprayer for one minute at twice per day during two months. Concentrations of odorous compounds from air in the room of the swine feeding operation were analyzed at four times during two months. Levels of butyric acid, valeric acid, i-butyric acid, ivaleric acid, skatole, methylmercaptan, and trimethylamine tended to decrease in C. obtus extract spray treatment group compared to the non-spray treatment group (P > 0.05). Odor activity values of butyric acid, valeric acid, skatole and trimethylamine were higher than other odorous compounds and decreased by 72%, 76%, 54% and 20%, respectively, in C. obtus extract spray treatment group compared to the non-spray group. Taken together, C. obtus extract showed an odor reducing capability in the air of a swine feeding operation suggesting that it possesses anti-bacterial properties as well as having a dust removal and masking effect.