• Korean Journal of Weed Science
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• v.16 no.2
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• pp.150-159
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• 1996

This study was conducted to investigate the inhibition of protox activity and the PPIX accumulation of the oxyfluorfen-tolerant and-susceptible rice cultivars with barnyardgrass, a typical susceptible weed in accordance by oxyfluorfen treatment. The susceptible rice cultivars and barnyardgrass showed more inhibition of protox activity due to the treatment of oxyfluorfen than the tolerant rice cultivars. Especially in the concentration at $10^{-6}$M treatment, protox activity of the susceptible rice cultivars and barnyardgrass were the completely inhibited but the tolerant rice cultivars kept 32~59% of activity compared to the control. As the treatment concentration increased, the content of PPIX accumulation increased and it increased untill four hours of light exposure but it tended to decrease these after. The content of PPIX accumulation by the treatment of oxyfluorfen was more pronounced in the light condition than in the dark. Under the light and dark conditions, the susceptible rice cultivars and barnyardgrass showed more PPIX accumulation than the tolerant rice cultivate. Especialiy the susceptible barnyardgrass had more than the rice. With the treatment of GC and DA, tetrapyrrole biosynthesis inhibitor, the herbicidal activity by oxyfluorfen was inhibited, and the susceptible rice cultivars and barnyardgrass tended to have less effective than the tolerant rice cultivars and the content of chlorophyll or PPS accumulation tended to be similar.

• Korean Journal of Agricultural Science
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• v.32 no.2
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• pp.233-241
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• 2005

The objective of this study was to investigate the effect of odor removal such as $NH_3$, volatile organic acid (VOA) during the pig manure composting using of the Pyroligneous acid liquor (PAL). The odor removal efficiencies were evaluated throughout the dilution rates (${\times}0$, ${\times}100$, ${\times}300$) of PAL. The results of the study are as followings. $NH_3$ content in all treatments (volume 10L) was approximately 8 mg/kg in compost piles on the first day. In the case of control treatment, it was increased by 46 mg/kg within 10 days and was not detected after 25 days. In contrast, those levels in PA-100 and PA-300 treatments were similar values at 38 mg/kg within 6 days and decreased after 15 days. And GC. equipment was used to analyze the volatile organic acids (acetic acid, butyric acid, isobutyric acid, isovaleric aicd, 2,3-methylbutyric aicd, and propionic acid). The concentration of acetic acid and butyric acid were the higher than other VOAs during the initial composting day and sharply declined after 15 days. The VOAs in the control treatment were detected until 40 days, but PA-100 and PA-300 treatments were not measured after 15 days. The PA-100 in all treatments was the most effective treatment for $NH_3$ gas and VOAs reduction during composting. In addition, these studies for the odor reduction in compost manufacture process would have to research on more effective methods for the PAL utilization in agro-biological aspects.

• KSBB Journal
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• v.24 no.1
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• pp.41-46
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• 2009

Vegetable oils are desirable inexpensive feedstocks for various bioproducts. The content of unsaturated fatty acids such as oleic and linoleic acids are 22% and 55% for soybean oil, 26% and 60% for corn oil, and 61% and 21% for canola oil, respectively. Keto and hydroxy fatty acids are useful industrial chemicals, used in plasticizer, surfactant, lubricant and detergent formulations because of their special chemical properties such as higher viscosity and reactivity compared with other fatty acids. In this study, a microbial isolate, Flavobacterium sp. strain DS5 (NRRL B-14859), was used to convert oleic acid to 10-ketostearic acid (10-KSA) via 10-hydroxystearic acid (10-HSA). Two bioconversion products, 10-KSA and 10-HSA, were quantitatively and qualitatively analyzed using gas chromatography, gas chromatography-mass spectrometry, and $^1H-$ and $^{13}C$-nuclear magnetic resonance. The maximum production of 10-KSA and 10-HSA in flask cultures were 3.4 g/L and 0.5 g/L, respectively. The optimum concentrations of glucose and yeast extract, addition time and volume of oleic acid for 10-KSA production were less than 20 g/L, more than 5 g/L, 18 hand 0.3 ml/50 ml, respectively.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.827-833
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• 1996

Along with the increased necessity for an efficient utilization of Korean wild edible plants growing in fields and mountains, attempts were made to investigate the patterns of flavor changes accompanied hy various conditions of dispersion medium. The effect of various pH values and concentration of sucrose or NaCl of dispersion medium on volatile flavor patterns was investigated to evaluate the applicability of flavor components extracted from Capsella bursa-pastoris for food industry. Essential oils from this wild plant were isolated by simultaneous steam distillation-extraction (SDE) method using diethyl ether as solvent. Concentrated samples were analyzed s chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS). Most volatile flavor components of Capsella bursa-pastoris showed good recovery when steam distilled at pH 7 by SDE method. Increasing concentration of sucrose and 15% by NaCl, resulted in greater numbers of identified flavor components from Capsella bursa-pastoris.

• Journal of the Korean Wood Science and Technology
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• v.39 no.1
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• pp.95-103
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• 2011

We have investigated pretreatment of waste wood using milling refinery combined with poping method, which can save energy for pretreatment and enzyme loading for enzymatic hydrolysis. The chemical analysis of holocellulose of non and popping treated waste wood showed 65.9% and 58.8%, and the lignin, organic extracts and ash were increased by 3%, 4% and 0.7% after pretreatment, respectively. The reducing sugar yields of pretreated waste wood were increased four times more than non-pretreated one and the synergistic effect of cellulase and xylanase were evaluated compare with individual enzyme treatment. Especially, enzyme cocktail (cellulase 50 U and xylanase 50 U) treatment was very efficient in 1% substrate (50 mg). Also, glucose and xylose conversion rate of pretreated waste wood by GC analysis were 45.9% and 38.7%, respectively.

• Korean Journal of Microbiology
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• v.50 no.3
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• pp.210-215
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• 2014

Pseudomonas nitroreducens TX1 was isolated from a rice field drainage in Taiwan. The bacterium is of special interest because of its capability to use a group of nonionic surfactants such as alkylphenol polyethoxylates even at high concentrations as a sole carbon source. In this study, a small cryptic circular plasmid, pTX1, was characterized from P. nitroreducens TX1. It is 2,286 bp in length with a GC content of 63.3% and harbors three open reading frames, $Rep_{pTX1}$ and functionally unidentified ORF1 and ORF2. The predicted $rep_{pTX1}$ gene product is homologous to Rep proteins of plasmids belonging to the pC194/pUB110 family, which is predominantly found in Gram-positive bacteria and is known to replicate by the rolling-circle mechanism. The copy number of pTX1 was estimated to be about 150 in each cell. Based on the genetic fingerprints and comparison with other plasmids, it is concluded that pTX1 replicates by a rolling circle mechanism which is rarely found for Pseudomonas plasmids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.513-518
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• 2005

Volatile compounds of $\gamma-irradiation$ leeks (Aillum tuberosum R.) were isolated by simultaneous steam distillation and extraction method (SDE) and analyzed by gas chromatography/mass spectrometry (GC/MS) along with the non-irradiated sample. Leeks were irradiated at dose of 20 kGy and non-irradiated samples were considered as control sample. 56 and 54 compounds were identified in non-irradiated and irradiated samples, respectively. These components included the functional groups; alcohols, aldehydes, esters, ketones, N- and S-containing compounds. S-containing compounds such as dimethyl trisulfide, methyl-(Z)-l-proenyl trisulfide, dimethyl disulfide, 3-ethyl-l,2-dithi-5-ene and methyl allyl disulfide were the major compounds. Methyl-(Z)-l-propenyl trisulfide, diallyl trisulfide, (E)-2-hexanal and 3-ethyl-l,2-dithi-5-ene were clearly decreased by the $\gamma-irradiation$, but dimethyl disulfide, diallyl sulfide, allyl methyl sulfide and pyridine were increased by the $\gamma-irradiation$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.775-783
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• 2015

This study was carried out to investigate the physicochemical properties and volatile ingredients of Jeju Apple mango subjected to different extraction methods and GC/MS. The crude protein, fat, and ash contents were $0.22{\pm}0.01$, $0.09{\pm}0.00$, and $0.27{\pm}0.02%$, respectively, and contents of free sugar increased in the order of sucrose, fructose, and glucose, whereas maltose, lactose, and galactose were not detected. The numbers of volatile flavor compounds obtained by the SE (solvent extraction), SDE (simultaneous steam distillation extraction), and SPME (solid-phase micro-extraction) methods were 51, 59, and 71, respectively. The percentages of extracted volatile flavor compounds in mango were 11.44, 15.68, and 73.54% by the SE, SDE, and SPME methods, respectively. The most abundant compounds found in Jeju Apple mango were terpenes and their derivatives, which accounted for 44.49~94.57% of total volatiles obtained. SPME method was considered to be the most effective extraction method in terms of the numbers of detected compounds and their amounts. ${\delta}$-3-Carene was identified as the dominant compound in mango, whereas ${\alpha}$-phellandrene, ${\gamma}$-terpinene, trans-${\beta}$-ocimene, ${\alpha}$-terpinolene, limonene, ${\alpha}$-pinene, and furaneol were the next important compounds.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.337-345
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• 1996

This study was conducted to investigate the protox activity, the PPIX accumulation and the activity of antioxidative enzymes of the oxyfluorfen-tolerant and -susceptible rice cultivars by oxyfluorfen and oxytluorfen-similar herbicides treatment. When treated with acifluorfen, bifenox or oxadiazon, the oxyfluorfen-tolerant rice cultivars showed less decreased in fresh weight than the susceptible rice cultivars. The inhibition of protox activity was in the order of acifluorfen > oxyfluorfen > bifenox > oxadiazon, and the PPIX accumulation was in the sequence of oxadiazon > acifluorfen > oxyfluorfen > bifenox. The inhibition of protox activity and the PPIX accumulation by the herbicide was greater in the susceptible rice cultivars than in the tolerant rice cultivars. The effect inhibiting the decrease of chlorophyll content resulting from the treatment of GC, tetrapyrrole biosynthesis inhibitor, was in the order of oxyfluorfen > acifluorfen > bifenox > oxadiazon, and the tolerant rice cultivar had more than the susceptible rice cultivar. In the treatment of DPE and oxadiazon, the activities of MDAR, POX and GR was higher in the tolerant rice cultivar than in the susceptible rice cultivar, and in the case of POX isozyme the activities of main D and E bands increased in the tolerant rice cultivars at tested herbicides but they didn't in the susceptible rice cultivar.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.123-131
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• 2018

The objective of this study was to evaluate the effect of roasting degree of barley on aroma characteristics of boricha (barley tea) using solvent-assisted flavor evaporation-gas chromatography-mass spectrometry and gas chromatography-olfactometry. Fifteen volatile compounds including pyrazine, ethylpyrazine, butyrolactone, and guaiacol were considered important volatile compounds, which are generated by roasting barley, because concentrations of those volatiles were significantly increased (p<0.05) as roasting degree of barley was darker. Guaiacol (smoky), furfuryl alcohol (burnt sugar), and furfural (caramel) were detected as aroma-active compounds of boricha with high intensity. Aroma intensity of aroma-active compounds in boricha increased with increase in roasting degree of barley. However, one unknown compound with burnt smell was detected as off-flavor in dark roasted barley. Therefore, it is implied that medium roasting of barley is desirable during boricha manufacturing. Furthermore, boricha manufactured with steamed barley contained more abundant volatile flavor compounds, which may lead to better aroma quality of boricha.