• KSBB Journal
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• 제22권2호
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• pp.84-90
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• 2007

본 연구에서는 고가의 TreH를 형질전환한 대장균으로부터 생산하고 부분적으로 정제한 후, 에폭시에 고정화하고 트레할로스-FIA 시스템에 이용하였다. 산소 전극을 이용한 트레할로스 검출 방법과 분광학적 방법을 이용한 트레할로스 검출 방법을 비교하고, 공정에서의 온라인 모니터링의 가능성을 검토하였다. 산소 전극을 이용한 분석의 경우 다른 대사 물질로 인한 간섭현상이 상대적으로 적고 검출 가능한 농도가 0.1$\sim$1.0 g/L로 많은 량의 트레할로스를 생산하는 공정을 모니터링할 경우 적합한 시스템임을 알 수 있었다. 반면 분광학적 방법으로 트레할로스를 검출한 실험의 경우 TreH와 GOD/HRP를 고정하여 실험한 경우와 TreH만 고정하고 GOD와 HRP를 직접 주입하는 방식을 비교했을 때 검출 가능한 농도는 0.01$\sim$0.2 g/L로 낮은 농도의 트레할로스를 모니터링할 경우에 적합하다. 그러나 ABTS나 GOD, HRP의 주입량 등 경제성과 운전이 편이성 등을 고려할 경우 GOD와 HRP를 직접 주입하는 시스템이 가장 효과적임을 알 수 있었다. 이 시스템을 이용하여 소형 생물반응기 내 트레할로스의 농도를 온라인 모니터링한 결과는 오프라인 값과 매우 잘 일치함을 보였다. 생물공정에서 트레할로스의 온라인 모니터링이 FIA 기술에 의해 가능함을 확인하였다.

• Mycobiology
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• 제43권3호
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• pp.184-194
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• 2015

A compressive description of tropical milky white mushroom (Calocybe indica P&C var. APK2) is provided in this review. This mushroom variety was first identified in the eastern Indian state of West Bengal and can be cultivated on a wide variety of substrates, at a high temperature range ($30{\sim}38^{\circ}C$). However, no commercial cultivation was made until 1998. Krishnamoorthy 1997 rediscovered the fungus from Tamil Nadu, India and standardized the commercial production techniques for the first time in the world. This edible mushroom has a long shelf life (5~7 days) compared to other commercially available counterparts. A comprehensive and critical review on physiological and nutritional requirements viz., pH, temperature, carbon to nitrogen ratio, best carbon source, best nitrogen source, growth period, growth promoters for mycelia biomass production; substrate preparation; spawn inoculation; different supplementation and casing requirements to increase the yield of mushrooms has been outlined. Innovative and inexpensive methods developed to commercially cultivate milky white mushrooms on different lignocellulosic biomass is also described in this review. The composition profiles of milky white mushroom, its mineral contents and non-enzymatic antioxidants are provided in comparison with button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Antioxidant assay results using methanol extract of milky white mushroom has been provided along with the information about the compounds that are responsible for flavor profile both in fresh and dry mushrooms. Milky white mushroom extracts are known to have anti-hyperglycemic effect and anti-lipid peroxidation effect. The advantage of growing at elevated temperature creates newer avenues to explore milky white mushroom cultivation economically around the world, especially, in humid tropical and sub-tropical zones. Because of its incomparable productivity and shelf life to any other cultivated mushrooms in the world, milky white mushroom could play an important role in satisfying the growing market demands for edible mushrooms in the near future.

• Molecules and Cells
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• 제43권3호
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• pp.286-297
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• 2020

Mammalian patatin-like phospholipase domain containing proteins (PNPLAs) play critical roles in triglyceride hydrolysis, phospholipids metabolism, and lipid droplet (LD) homeostasis. PNPLA7 is a lysophosphatidylcholine hydrolase anchored on the endoplasmic reticulum which associates with LDs through its catalytic region (PNPLA7-C) in response to increased cyclic nucleotide levels. However, the interaction of PNPLA7 with LDs through its catalytic region is unknown. Herein, we demonstrate that PNPLA7-C localizes to the mature LDs ex vivo and also colocalizes with pre-existing LDs. Localization of PNPLA7-C with LDs induces LDs clustering via non-enzymatic intermolecular associations, while PNPLA7 alone does not induce LD clustering. Residues 742-1016 contains four putative transmembrane domains which act as a LD targeting motif and are required for the localization of PNPLA7-C to LDs. Furthermore, the N-terminal flanking region of the LD targeting motif, residues 681-741, contributes to the LD targeting, whereas the C-terminal flanking region (1169-1326) has an anti-LD targeting effect. Interestingly, the LD targeting motif does not exhibit lysophosphatidylcholine hydrolase activity even though it associates with LDs phospholipid membranes. These findings characterize the specific functional domains of PNPLA7 mediating subcellular positioning and interactions with LDs, as wells as providing critical insights into the structure of this evolutionarily conserved phospholipid-metabolizing enzyme family.

• 공업화학
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• 제27권2호
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• pp.145-152
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• 2016

본 연구에서는 전기화학적 바이오센서의 포도당 감지능을 높이고자 금 나노 입자가 분산된 다중벽탄소나노튜브(multi-walled carbon nanotube, MWCNTs)에 CuO를 도입하였다. 금 나노 입자로 인하여 나노 클러스터(cluster) 형상을 갖는 CuO가 합성되었으며, 이는 포도당 감지능력에 매우 큰 영향을 나타내었다. 0.1 mole의 CuO가 합성되었을 때 CuO/Au@MWCNTs 나노복합재를 전극재료로서 바이오센서는 $504.1{\mu}A\;mM^{-1}cm^{-2}$으로 가장 높은 민감도를 보여주었으며, 이 값은 MWCNTs만을 전극으로 이용할 때보다 약 4배 정도 컸다. 또한, 0-10 mM의 긴 선형 구간(linear range)과 0.008 mM의 낮은 LoD (limit of detection) 값을 보여주었다. 이러한 실험 결과들은 CuO/Au@MWCNTs 나노복합재가 CuO를 이용한 다른 전기화학적 바이오센서보다 우수하다는 것을 입증하였으며, 이는 나노 클러스터 형상의 CuO가 포도당 감지에서 전기화학적 반응에 유리하기 때문으로 사료된다.

• 한국식품위생안전성학회지
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• 제27권4호
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• pp.401-405
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• 2012

천연 갈변 및 미생물 억제제 소재를 발굴하기 위해 신선절단 사과에 백년초추출물을 처리하여 색도변화, peroxidase 활성, 황색포도상구균 생육을 조사하였다. 신선절단 사과의 L값은 백련초 추출물 처리구가 대조구에 비해 유의적으로 감소폭이 적어 갈변억제가 나타난 것을 확인할 수 있었으며, a값은 저장기간이 경과함에 따라 증가하였으며 백련초 추출물 처리구는 2일째부터 갈변억제효과를 보였다. Peroxidase 활성도 백년초 추출물 처리구에서 저장기간이 경과함에 따라 갈변억제효과를 확인하였다. 신선절단 사과에서 백년초 추출물 25 mg/mL 이상 처리구에서 유의적으로 황색포도상구균 생육억제 효과가 나타났으며, 온도별로는 $21^{\circ}C$ 저장시 억제효과가 더 큰 것으로 판단되었다. 특히 100 mg/mL 처리구에서 4일째부터 황색포도상구균이 검출한계 이하로 관찰되어 생육억제에 매우 효과적임을 확인 할 수 있었다. 따라서 본 연구결과, 백년초 추출물 처리는 신선절단 사과의 저장 중에 갈변억제 및 황색포도상구균의 생육억제에 효과적인 천연물이며, 향후 신선절단식품의 품질유지에 효과적인 식품첨가제로서 개발 가능하리라 판단된다.

• 한국어병학회지
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• 제21권2호
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• pp.81-91
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• 2008

Vibrio harveyi, one of the major causal agent of vibriosis, affects a diverse range of marine vertebrates and invertebrates over a wide geographical area. The aims of this study were to investigate the characteristics of extracellular products (ECPs) from an isolate of the pathogenic non‐luminous V. harveyi and the luminous V. harveyi. And ECPs of V. harveyi were examined the pathogenicity to the black rockfish, Sebastes schlegeli, and histopathological traits of internal organs injected by ECPs. Four strains of V. harveyi cultures produced ECPs showing various enzymatic activites (caseinase, gelatinase, phospholipase, lipase, haemolysin). The ECPs showed strong cytotoxicity on macrophages of black rockfish, Sebastes schlegeli and olive flounder, Paralichthys olivaceus. Especially, the virulence of ECPs from the isolate of V. harveyi FR 2 was higher in the intraperitoneally injected black rockfish. Also, the ECPs of V. harveyi FR 2 caused the expansion of sinusoids in the liver, the activation of ellipsoid in the spleen and the sloughing of the epidermal cell in the intestine. It was suggested that the ECPs from V. harveyi play an important role in the pathogenicity process of the V. harveyi.

• 한국식품영양학회지
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• 제30권5호
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• pp.853-859
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• 2017

This study was conducted in an effort to investigate the effect of Maillard reaction products (MRPs) on enzymatic browning of burdock and their anti-oxidant activity. The MRPs were prepared by heating glucose and amino acids at $90^{\circ}C$, which served to produce a strong inhibitory effect on burdock polyphenol oxidase. As the reaction time of the solution containing glucose and amino acid increased at $90^{\circ}C$, the production of MRPs increased and intensity of the brown color deepened. When MRPs were prepared by heating at $90^{\circ}C$ for five hours, the absorbance of MRPs from glucose and lysine was 6.44, while those of glucose and glycine was 1.95. The MRPs synthesized from the glucose and lysine also reduced the pH of MRPs from 5.60 to 4.51, but those from glucose and glycine decreased slightly from 5.57 to 5.33. The Michealis-Menten constant value ($K_m$) of burdock PPO with pyrocatechol as a substrate was 16.0 mM, and MRPs were a non-competitive inhibitor against burdock PPO. The anti-oxidant activity of MRPs was measured by evaluating its radical scavenging activities of DPPH radicals, ABTS radicals and reducing power. The color intensity of MRPs produced by lysine and glucose were deeper than that produced by glucose and glycine. It was also found that MRPs produced from glucose and lysine exhibited stronger anti-oxidant properties than those produced by glucose and glycine.

• Korean Chemical Engineering Research
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• 제57권5호
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• pp.606-610
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• 2019

본 연구에서 우리는 보론 도핑된 다이아몬드 나노물질을 이용하여 유연성 탄소 섬유 기반의 전극(CF-BDD 전극)을 개발하고, 이를 비효소적 글루코스 센서에 적용하여 전기화학적 특성을 확인하였다. 이 전극은 탄소 섬유 표면에 정전하 자기조립법을 이용하여 BDD 층을 증착하여 제작하였다. 이 전극 물질의 표면 구조는 주사전자 현미경(SEM)을 이용하여 분석하였으며, 전기화학적 특성 및 센싱 성능 분석은 시간대전류법(CA)와 순환전압 전류법(CV), 전기화학 임피던스(EIS)으로 실행하였다. 제작된 CF-BDD 전극은 산화-환원 화학종과 전극 계면 간의 effective direct electron transfer와 large effective surface area, high catalytic activity의 우수한 특성들을 보였다. 결과적으로, CF 센서와 비교에서 CF-BDD 센서는 더 넓은 선형 농도 범위(3.75~50 mM)와 더 빠른 감응 시간(3초 이내), 더 높은 감도(388.8 nA/mM) 등의 향상된 센싱 특성을 보였다. 따라서, 본 연구에서 개발된 전극 물질은 다양한 전기화학 센서 뿐 아니라, 웨어러블 센서 소재로도 활용 가능할 것으로 기대된다.

• 대한약침학회지
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• 제22권3호
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• pp.140-146
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• 2019

Objectives: Venomous fishes have different pharmacological effects and are useful. Among the venomous fish, stonefishes; especially Pseudosynanceia melanostigma has various pharmacological effects on the nervous, muscular and cardiovascular system of humans. In this study, toxicological characteristics, some blood effects, pharmacological and enzymatic properties of Pseudosynanceia melanostigma venom was investigated. Methods: Crude venom purified by using gel filtration chromatography and the molecular weights of the venom and its fractions were estimated. The approximate LD values of this venom were determinedand the effects of LD50 dose on the blood of rabbits were studied. Hemolytic and Hemorrhagic activity of the venom sample was determined. In this case coagulation tests were performed. Results: The LD50 of the Pseudosynanceia melanostigma crude venom was also determined to be $194.54{\mu}g/mouse$. The effect of two doses of LD50 showed a non-significant differences decrease in RBCs and MCV. In other cases, the results showed significant differences in WBC, Plt, Hb, MCH, MCHC and HCT; also it's showed a significant decrease. WBC count showed a significant increase with two doses of LD50 groups. The prothrombin time and partial prothrombin time were increased after venom treatment. As well as bleeding and clotting time were increased. According to the results, a minimum dose for Haemorrhagic effect $40{\mu}g$ was obtained. Conclusion: Venom of Pseudosynanceia melanostigma has inhibitory effect on platelet aggregation that can be used to design and develop of anticoagulant drugs.

• 대한약침학회지
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• 제22권2호
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• pp.83-89
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• 2019

Introduction: Oxidative stress (OS) during uncontrolled hyperglycemia has a pivotal role in pancreatic dysfunction. Our study aimed to demonstrate that crocin can potentiate anti-oxidant defense systems of pancreatic cells to improve oxidative stress. Methods: Male Wistar rats were divided randomly into four groups: a normal group, a normal-treated group, a diabetic group and a diabetic-treated group (n = 6 rats per group). Diabetes was induced by a single dose of streptozotocin (45 mg/kg/IV). The treated groups received crocin daily for 8 weeks (40 mg/kg/IP). At the end of the experiment, rats were sacrificed and pancreas tissue was obtained. Subsequently, the concentrations of malondialdehyde (MDA), nitrate and glutathione as well as the enzymatic activities of catalase and superoxide dismutase (SOD) were determined in all animals. Data were analyzed by two-way ANOVA with appropriate post hoc testing and a probability value of P < 0.05 was considered to represent a statistically significant difference in mean values. Results: Uncontrolled hyperglycemia weakened the anti-oxidant system by decreasing SOD and catalase enzyme activity in pancreatic tissues and induced OS by increasing the MDA content in diabetic non-treated animals. Crocin potentiated the anti-oxidant defense system by increasing the activity of both SOD and catalase, and improved OS by diminishing MDA production in pancreatic cells of rats contained in the diabetic-treated group. Conclusion: Based on our results, it is concluded that uncontrolled hyperglycemia can weaken the anti-oxidant defense system and cause the development of OS. Also, crocin can improve OS in pancreatic cells by potentiating the anti-oxidant defense system.