• Analytical Science and Technology
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• v.18 no.5
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• pp.396-402
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• 2005

We try to look for optimum conditions of pre-reductants like L-Cysteine, KI and $FeSO_4$ when analyzing inorganic arsenic by using hydride generation-atomic absorption spectrometry, and run a comparative study of effect in the analysis of them. Also, we separated and analyzed only inorganic arsenic by using $H_2SO_4$-trap to eliminate organic arsenic which are MMA(monomethylarsonate) and DMA(dimethylarsinate). Under the conditions of mixture acid of 1.8 M HCl and 0.08 M $HNO_3$, arsenic standard solution of 20 ppb have more higher absorbance than without adding acid. In case of L-Cysteine, As(V) completely reduces into As(III) when 0.5 g of L-Cysteine is reacted more than 30 mins. in weak acid condition of approximately 0.07 M $HNO_3$ or HCl. In the event of KI, As(V) completely reduces into As(III) when 3 g of KI is reacted more than 1hour in acid condition of 0.8 M $HNO_3$. On the occasion of $FeSO_4$, the inside of tube is blocked by precipitation by mixture reaction of $NaBH_4$ and $Fe^{2+}$, therefore, comparing to other pre-reductants, reproducibility of efficiency of reducing As(V) to As(III) is low. To evaluate the accuracy of the analytical results, we use NIST SRM 1643C Trace Elements in Water ($82.1{\pm}1.2ng/mL$). The results are satisfactory.

• Microbiology and Biotechnology Letters
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• v.48 no.4
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• pp.463-470
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• 2020

The JS18 strain was isolated from an old tree forest and produced extracellular enzymes that decolorize synthetic melanin. Phylogenetic analysis, based on the internal transcribed spacer (ITS) sequence, indicate that JS18 belongs to the Trametes velutina species. JS18 demonstrated laccase activity but no manganese peroxidase or lignin peroxidase activity. Batch culture indicated that the melanin decolorization activity of JS18 strain originated from the laccase. Syringic acid and CuSO4 induced maximum laccase production, yielding 98 U/ml laccase activity after cultivation for 7 days at 25℃. T. velutina secretes an extracellular laccase in GYP medium, and this enzyme was purified using (NH4)2SO4 precipitation, Hi-trap Q Sepharose columns and gel filtration. The molecular weight of the purified enzyme was estimated to be 67 kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis. This enzyme produced 80% of its melanin decolorization activity within the first 24 h of evaluation in the presence of 1-hydroxybenzotriazole (HBT), while only about 4% of the melanin was decolorized in the absence of the mediator. The greatest decolorization was observed at 1.5 mM/l HBT, which decolorized 81% of the melanin within the first 24 h. The optimum pH and temperature for this decolorization were found to be 5.0 and 37℃, respectively. Our results suggest the possibility of applying HBT induced T. velutina JS18 laccase-catalyzed melanin decolorization.

• Korean journal of food and cookery science
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• v.29 no.5
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• pp.453-462
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• 2013

Recently, two formulas of sulgidduk added to pine needle juice (PNJ) with various physiological activities were developed for metabolic syndrome patients in our lab. According to previous studies, cooking may alter antioxidant properties by initiating destruction, release or transformation of antioxidant compounds contained in food. Therefore, the aim of this study was to compare the antioxidant activities and antigenotixic effects of sulgidduk with/without PNJ and to note changes in these activities after cooking. The ingredients of sulgidduk was added on the basis of 100% rice flour as follows: conventional sulgidduk (S): 1.5% salt, 30.0% sugar; PNJ added to sulgidduk A (PS-A): 1.4% salt, 30.0% sugar, and 1.0% PNJ; PNJ added to sulgidduk B (PS-B): 1.5% salt, 21.4% sugar, and 1.4% PNJ. Ethanol and water extracts of sulgidduk were analyzed for the total phenolic content (TPC), DPPH radical scavenging activity (DPPH RSA), total radical-trapping antioxidant potential (TRAP), oxygen radical absorbance capacity (ORAC), and antigenotoxic effect by comet assay. The ethanol extracts PS-A and PS-B showed higher TPC and antioxidant activities (DPPH RSA, TRAP, and ORAC) than did the S ethanol extract before cooking. The more PNJ was added, the higher TPC and anitoxidant activities were observed in sulgidduk (PS-A$200{\mu}M$ of $H_2O_2$. Taken together, this study suggests that sulgidduk added to 1.44% of pine needle juice may be a good option antioxidant and antigenotoxic source.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1370-1377
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• 2013

Rice is widely grown in Asia and is one of the major dietary staples in the world. Also, rice contains antioxidants which can prevent from oxidative stress related diseases, including cancer, atherosclerosis, and diabetes. Because the rice is consumed cooked, the effect of the cooking process on the antioxidative and antigenotoxic properties of rice is lacking. The aim of this study was to determine the effects of cooking on the antioxidant and antigenotoxic effects of white rice (WR), brown rice (BR), and germinated brown rice (GBR). The antioxidant activities were measured for total phenolic content (TPC), DPPH radical scavenging activity (DPPH RSA), total antioxidant capacity (TRAP), and oxygen radical absorbance capacity (ORAC). The highest TPC was found in uncooked BR (18.4 mg gallic acid equivalent/100 g). After cooking, the TPC of WR significantly increased, while the TPC of BR and GBR were reduced by 47.7% and 36.7%, respectively. The $IC_{50}$ for DPPH RSA was not significantly different in uncooked rice, while the DPPH RSA of WR and GBR decreased after cooking and the DPPH RSA of BR significantly increased. TRAP values in BR and GBR increased after cooking, while the value of WR decreased. The ORAC values of uncooked WR, BR, and GBR were 5.3, 4.3, and $3.9{\mu}M$ trolox equivalent at the concentration of $50{\mu}g/mL$. After cooking, the ORAC value of BR remained unchanged, while the value of GBR increased and the value of WR decreased. The antigenotoxic activities of WR, BR, and GBR were determined by measuring the inhibitory effects of $H_2O_2$-induced DNA damage on human leukocytes using the comet assay. The results showed that all rice tested showed a significant antigenotoxic effect against oxidative stress, except for the cooked white rice. Overall, our results indicate the addition of brown rice and/or germinated brown rice to cooked white rice is a good option for improving the benefits of rice.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.583-591
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• 2002

Biodegradation of fat, oil, and grease (FOGs) plays an Important role in wastewater management and water pollution control. However, many industrial food-processing and food restaurants generate FOG-containing waste waters for which there Is no acceptable technology for their pretreatment. To solve these problems, this study evaluated the feasibility of effective FOG-degrading microorganisms on the biodegradation of olive oil and FOG-containing wastewater. Twenty-two strains capable of degrading FOGs were isolated from five FOG-contaminated sites for the evaluation of their FOG degradation capabilities. Among twenty-two strains tested, the lipase-producing Pseudomonas sp. strain D2D3 was selected for actual FOG wastewater treatment. Its biodegradability was performed at 3$0^{\circ}C$ and pH 8. The extent of FOG removal efficiency was varied for each FOG tested, being the highest for olive oil and animal fat (94.5% and 94.4%), and the lowest for safflower oil (62%). The addition of organic nitrogen sources such as yeast extract, soytone, and peptone enhanced the removal efficiency of FOGs, but the addition of the inorganic nitrogen nutrients such as $NH_4$Cl and $(NH_4)_2SO_4$ did not increase. The $KH_2PO_4$ sources in 0.25% to 0.5% concentrations showed more than 90% degradability. As a result, the main pathway for the oxidation of fatty acids results in the removal of two carbon atoms as acetyl-CoA with each reaction sequence: $\beta$-oxidation. Its lipase activity showed 38.5 U/g DCW using the optimal media after 9 h. Real wastewater and FOGs were used for determining the removal efficiency by using Pseudomonas sp. strain D2D3 bioadditive. The degradation by Pseudomonas sp. strain D2D3 was 41% higher than that of the naturally occurring bacteria. This result indicated that the use of isolated Pseudomonas sp. strain D2D3 in a bioaugmentating grease trap or other processes might possibly be sufficient to acclimate biological processes for degrading FOGs.

• Journal of Life Science
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• v.13 no.3
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• pp.308-313
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• 2003

The collagenase gene from Vibrio parahaemolyticus 04 was subcloned into an expression vector pET-29b. The recombinant collagenase was expressed in Escherichia coli BL2l(DE3) and partially purified by Hi-Trap affinity and Sephacryl S-100 size exclusion chromatographies. The recombinant enzyme was purified by 43.7-fold and the yield was 73%. SDS-PAGE revealed that the molecular weight of the enzyme was approximately 35 kDa. Substrate specificity study of the enzyme displayed that the enzyme showed the highest activity with the type I collagen and the synthetic peptide, Z-GPGGPA, indicating that the enzyme was indeed a collagenase. The enzyme showed broad pH optimum around pH 6-12 and was stable between pH 5.5 and 11.5. The optimum temperature for the type I collagen degradation was $35^{\circ}C$. The thermostability measurement of the enzyme indicated that the enzyme was stable up to $55^{\circ}C$, but the activity was diminished quickly above $60^{\circ}C.$

• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1120-1127
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• 2017

Marasmius scorodonius secretes an extracellular laccase in potato dextrose broth, and this enzyme was purified up to 206-fold using $(NH_4)_2SO_4$ precipitation and a Hi-trap Q Sepharose column. The molecular mass of the purified laccase was estimated to be ~67 kDa by SDS-PAGE. The UV/vis spectrum of the enzyme was nontypical for laccases, and metal content analysis revealed that the enzyme contains 1 mole of Fe and Zn and 2 moles of Cu per mole of protein. The optimal pH for the enzymatic activity was 3.4, 4.0, and 4.6 with 2,2'-azino-bis(3-ethylbenzothazoline-6-sulfonate) (ABTS), guaiacol, and 2,6-dimethoxy phenol as the substrate, respectively. The optimal temperature of the enzyme was $75^{\circ}C$ with ABTS as the substrate. The enzyme was stable in the presence of some metal ions such as $Ca^{2+}$, $Cu^{2+}$, $Ni^{2+}$, $Mg^{2+}$, $Mn^{2+}$, $Ba^{2+}$, $Co^{2+}$, and $Zn^{2+}$ at a low concentration (1 mM), whereas $Fe^{2+}$ completely inhibited the enzymatic activity. The enzymatic reaction was strongly inhibited by metal chelators and thiol compounds except for EDTA. This enzyme directly decolorized Congo red, Malachite green, Crystal violet, and Methylene green dyes at various decolorization rates of 63-90%. In the presence of 1-hydroxybenzotriazole as a redox mediator, the decolorization of Reactive orange 16 and Remazol brilliant blue R was also achieved.

• Korean journal of applied entomology
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• v.14 no.3 s.24
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• pp.137-140
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• 1975

Field experiments on red-pepper were conducted in Suweon area during 1972-1974 to determine the seasonal fluctuation of Heliothis assulta H. using black light traps and direct counts. Adult moths emerged in late May, and showed three peaks of fluctuation from late June to middle July, from middle August to late August, and in mid-September. Eggs were first discovered in the field in early July, with peak incidence Iron late August to early September. Larval peaks occurred in late July to early August, in late August and mid-September to mid-October Initial hatching in the field occurred in early July. The numbers of the first larval generation were the highest. The parasitization ratio of Trichogramma spp. on eggs averaged 51 percent during mid-July to mid-September. The numbers of Trichogramma spp. emerging from one tobacco bud-worm egg ranged from one to four, but in most cases one or two egg parasitizing wasps emerged.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.325-334
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• 2013

The objective of this study was to compare the content and metabolic activities between fresh pine needle juice (PNJ) and fermented pine needle juice (FPNJ). A variety of factors were measured, including total phenolic content (TPC), antioxidant activity [DPPH radical scavenging activity (RSA), total radical-trapping antioxidant potential (TRAP), oxygen radical absorbance capacity (ORAC), cellular antioxidant capacity (CAC)], anti-genotoxic activity, ${\alpha}$-glucosidase inhibitory activity, and angiotensin converting enzyme (ACE) inhibitory activity. The TPC was $17.3{\pm}0.2$ and $4.6{\pm}0.0$ mg GAE/g in PNJ and FPNJ, respectively. The DPPH RSA, TRAP, and ORAC values increased in a dose-dependent manner for both PNJ and FPNJ, with significantly higher activities in PNJ than FPNJ. The CAC against AAPH-induced oxidative stress in HepG2 cells was protected by both PNJ and FPNJ. Pretreatment with PNJ and FPNJ in human leukocytes produced significant reductions in $H_2O_2$-induced DNA damage at a concentration of $50{\mu}g/mL$. ${\alpha}$-Glucosidase inhibitory activity was significantly higher in FPNJ than PNJ. The ACE inhibitory activity was about 87.1% and 60.0% in 1:1 diluted PNJ and FPNJ, respectively. This study suggests that the fermentation of PNJ could enhance the regulation of blood glucose metabolism and both PNJ and FPNJ might be a new potential source of natural antioxidant, anti-diabetic, and anti-hypertensive agents applicable to food.

• Korean journal of applied entomology
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• v.16 no.3 s.32
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• pp.171-179
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• 1977

Since the outbreak of the brown planthopper (Nilaparvata lugens) in 1915 caused tremendous losses in rice production, one of the more effective method of prevention of such a disaster could be the establishment of longterm forecasting system, In 1916 the author indicated there was a correlation between sunspot activities and brown planthopper and the white back planthopper outbreaks. However, the examples seem to be too small size to state a definite correlation. The purpose of the present study IS to revi~w the history of the brown planthopper outbreaks, and to establish a more effective forcasting system. The present forcasting methods are based on light trap catches of adults which already migrate into this country from mainland China. The regular cycle of 11.2 years of sunspot activity began in 1710, and was continued to present. To gather more records of brown planthopper, the author checked 'Joseon Wangjo Silrok' and analized the so-called 'Hwang' 'Hwang-chung' and 'Chung' which have multiple meanings, together with 'Samguk Sagi' 'Goryo Sa' and 'Munheon Bigo.' The results obtained by the about from review of these old literature citations revealed that ten species of insect and unknown species were involved: i. e., pine moth (Dendrolimus spectabilis), army worm (Mythimna separata), brown planthopper (Nilarvata lugens), white-back planthopper (Sogatella furcifera), migratory locust (Locutsa migratoria), rice stem borer (Chilo suppressalis,), mole cricket (Gryllotalpa africana), rice-plant weevil (Echinocnemus squameus), cut worm (Euxoa segetum), and mulberry pyralid Margaronia pyloalis) The suspected incidence of planthopper in old records expressed by 'Hwang' or 'Chung' revealed a total or 25 out of 37 in 'Samguk sagi,' 21 out of 49 in 'Goryo sa,' 9 of 73 in 'Wanjo-silrog,' and none of 8 in 'Munheon bigo' were planthoppers. Therefore, a total of 36 out of 167 records of insect incidence in the old literature can be possibly attributed to planthoppers. The brown planthopper and white-back planthopper migrate together to Korea every year from mainland China, However, the number of each species are differ by year. In 1975 outbreak the brown planthopper was dominant; and the white-back planthopper prevailed in 1946 and 1977 outbreaks, During the course of this study, the author was able to add a new record of outbreak of planthop per. In 1916 the white-back planthopper outbreak caused serious losses in Chungcheong-namdo and Jeonla-namdo, with losses estimated as high as 160 and 190 thousand seok (23.2 and 27.5 thousand M/T), in Naju and Secheon county, respectively. Since 1912, major outbreaks of brown planthopper or white-back planthopper have been recored 5 times. These occurrences coincide and well matched the period of minimum number of sunspots, With these authenticated records of planthoppers, the author believes there is a close correlation between brown planthopper and white-back planthopper outbreaks in Korea and sunspot activities. Therefore, in years of low number of sunspots, we should watch for and expect outbreaks of these. insects. At this time, it will be necessary to provide all possible prevention measures.