• Korean Chemical Engineering Research
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• v.56 no.5
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• pp.711-717
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• 2018

Human epidermal growth factor (hEGF) can stimulate the division of various cell types and has potential clinical applications. Since the protein contains three intra-molecular disulfide bonds, the high expression of active hEGF in Escherichia coli has not been well researched, We fused the hEGF gene with a small ubiquitin-related modifier gene (SUMO) by synthesizing an artificial SUMO-hEGF fusion gene that was highly expressed in E. coli (DE3) strain. The optimal expression level of the soluble fusion protein, SUMO-hEGF with IPTG (Isopropyl-${\beta}$-D-Thiogalactopyranoside), was up to 38.9% of the total cellular protein. The fusion protein was purified by Ni-NTA affinity chromatography and cleaved by a SUMO-specific protease to obtain the native hEGF, which was further purified by Ni-NTA affinity chromatography. The result of the reverse-phase HPLC showed that the purity of the recombinant cleaved hEGF was greater than 98%.

• Journal of dental hygiene science
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• v.19 no.3
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• pp.198-204
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• 2019

Background: Oxidative stress is a known to be associated with in the pathogenesis of many inflammatory diseases, including periodontitis. Ursolic acid is a pentacyclic triterpenoid with has antimicrobial, antioxidative, and anticancer properties. However, the role of ursolic acid in the regulating of osteogenesis remains undetermined. This study was aimed to elucidate the crucial osteogenic effects of ursolic acid and its ability to inhibit oxidative stress by targeting the immediate early response 3 (IER3)/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Methods: Cell proliferation was determined using water-soluble tetrazolium salt assay, cell differentiation was evaluated by alkaline phosphatase (ALP) activity, and formation of calcium nodules was detected using alizarin red S stain. Generation of reactive oxygen species (ROS) was determined using by DCFH-DA fluorescence dye in hydrogen peroxide ($H_2O_2$)-treated MG-63 cells. Expression levels of IER3, Nrf2, and heme oxygenase-1 (HO-1) were analyzed using western blot analysis. Results: Our results showed that ursolic acid up-regulated the proliferation of osteoblasts without any cytotoxic effects, and promoted ALP activity and mineralization. $H_2O_2$-induced ROS generation was found to be significantly inhibited on treatment with ursolic acid. Furthermore, in $H_2O_2$-treated cells, the expression of the early response genes: IER3, Nrf2, and Nrf2-related phase II enzyme (HO-1) was enhanced in the presence of ursolic acid. Conclusion: The key findings of the present study elucidate the protective effects of ursolic acid against oxidative stress conditions in osteoblasts via the IER3/Nrf2 pathway. Thus, ursolic acid may be developed as a preventative and therapeutic agent for mineral homeostasis and inflammatory diseases caused due to oxidative injury.

• Biomolecules & Therapeutics
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• v.1 no.2
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• pp.188-195
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• 1993

In order to understand the machanism of action and regulation of ${\beta}$-adrenergic receptor in terms of molecular level, the purification of receptor protein has a fundamental importance. Moreover, species differences among avian, amphibian and mammalian ${\beta}$-adrenergic receptors make it more important to purify mammalian ${\beta}$-adrenergic receptor. Because ${\beta}$-adrenergic receptor is an integral membrane protein, it must be solubilized from the membrane for the purification. The purpose of the present study was to solubilize and characterize the mammalian $\beta$-adrenergic receptor from guinea pig lung in quantities by more efficient and practical method eventually to purify receptor. Guinea pig lung membrane preparation was solubilized by sequential treatment of buffers containing low and high concentration of digitonin which are 0.2 and 1.2% respectively. About 50% of the total receptor pool was released by this double extraction procedure. The $\beta$-adrenoceptors in the digitonin extract were identified using the ${\beta}$-adrenergic antagonist, (-)-[$^3H$]-dihydroalprenolol ([$^3H$]DHA). The solubilized receptor retained all of the essential characteristics of membrane-bound receptor, namely saturability; stereoselectivity; high affinity to ${\beta}$-adrenergic drugs. For the measurement of soluble receptor activity, Sephadex G-50 chromatography method has been widely used. Inspite of its accuracy and wide acceptance, this technique employed troublesome column work which required long time to assay the activity of receptor. We employed another methods to measure receptor activity. When using 0.5% polyethylenimine pretreated GF/B glass fiber filter, filtration technique could be used to measure soluble receptor activity. This technique enabled us to reduce the total amount of time to assay by a factor of 4 as well as to detect soluble receptor. In the present study, we could establish more efficient and practical solubilization method of mammalian $\beta$-adrenergic receptor. The rapidity and high yield of this solubilization scheme, together with the favorable recovery of the receptor activity, are significant steps toward the ultimate purification of the mammalian $\beta$-adrenergic receptor. The result of this study together with more convenient purification method could provide large amount of purified receptor with ease for various research purposes.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.690-695
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• 1994

The perilla seed and the germinated perilla seed $(25{\sim}28^{\circ}C$, $2{\sim}3\;days)$ were extracted by n-hexane, and from the extracted oil the antioxidative components were separated, and then the effect of the change in the contents of antioxidative components by germination on the oxidative stability of the perilla oil was studied. The perilla oils were solved acetone and methanol, and kept at $-60^{\circ}C$ overnight and separated into the frozen oil fraction and unfrozen solvent soluble fraction. By comparing the antioxidative stability of the frozen oil fraction the antioxidative components in the perilla oil were found to be methanol soluble. The methanol soluble fraction of perilla oil was applied to silica gel column chromatography and the separated fractions were compared in terms of antioxidative activity. The fraction of n-hexane : ethyl acetate (7 : 3, v/v) showing the highest antioxidative activity was further separated by TLC. The components included in the band $(R_f\;0.71)$ showing the highest antioxidative activity was separated by HPLC. Four peaks were observed on the HPLC chromatogram and the peak areas were changed by germination (perilla seed : peak 1; 46.5%, peak 2; 25.6%, peak 3; 22.6%, germinated perilla seed : peak 1; 43.8%, peak 2; 20.6%, peak 3; 29.8%). The comparative change in the contents of these components was considered to be one factor affecting the antioxidative stability of perilla oil by germination.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.473-477
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• 2001

Chitosan has been used as an effective adsorbant for the treatment of wastewater from seafood processing. We investigated the effects of deacetylation degree (DD) and molecular weight (MW) of chitosan on protein adsorption ability and also the optimum conditions of chitosan treatment for protein adsorption in 3 kinds of protein (albumin, hemoglobin and albumin-myoglobin mixture) solutions. The higher deacetylation degree and the lower molecular weight chitosan, the higher adsorption for water soluble proteins was accomplished. The optimum pHs for adsorption of albumin, hemoglobin and albumin-myoglobin mixture (4: 1, w/w) were 4.0, 7.0 and 4.0 respectively and the optimum time was $3\~4$ hrs for all proteins. Sodium chloride in the model system of protein solution was a preventing factor for protein adsorption ability of chitosan (DD=$80\%$, MW=350 kDa).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.463-468
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• 1987

The present paper was investigated to elucidate the nitrite-scavenging ability of vegetable extracts. Vegetable extracts possessed the scavenging ability of nitrite. By fractionatioh of vegetable extracts,nitrite-scavenging ability of garlic (Allitum sativum for. Pekinense), chinese pepper (Zanthexylum schinifolium), onion (Allium cepa), welsh onion (Allium fistulosum) and ginger (Zingiber officinale) extracts were effective in the water-soluble fraction, but carrot (Daucus carota uar. sativa) in the methanol-soluble fraction. Nitrite-scavenging ability of vegetable extracts was also pH-dependent, highest at pH 1.2 and lowest at pH 6.0. Particularly, nitrite-scavenging abilities of water-soluble fractions obtained from garlic and chinese pepper were similar to that of L-ascorbic acid at pH 1.2. After vegetable extracts were treated with sodium borohydride, nitrite-scavenging ability was remarkably decreased at pH 1.2. It is assumed that reducing powers of vegetable extracts participated in their nitritescavenging abilities.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.469-475
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• 1987

The present paper was investigated to elucidate the nitrite-scavenging ability of seaweed extracts. Seaweed extracts possessed the scavenging ability of nitrite. By fractionation of seaweed extracts, nitrite-scavenging ability of laver(Porphyra tenera), sea lettuce(Enteromorpha compresa) extracts were effective in the water-soluble fraction, but sea mustard (Undaria pinnatifida), sea staghorn (Codium fragile) extracts in the methanol-soluble fraction. Nitrite scavenging ability of seaweed extracts was also pH-dependent, highest at pH1.2 and lowest at pH6.0. Particularly, nitrite-scavenging abilities of water-soluble fractions obtained from laver and sea lettuce were similar to that of L-ascorbic acid at pHl.2. After seaweed extracts were treated with sodium borohydride, nitrite-scavenging ability was remarkably decreased at pH1.2. It is assumed that reducing powers of seaweed extracts participated in their nitrite-scavenging abilities.

• Korean Journal of Microbiology
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• v.43 no.3
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• pp.166-172
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• 2007

ERM proteins transfer the methyl group to $A_{2058}$ in 23S rRNA, which reduces the affinity of MLS (macrolide-lincosamide-streptogramin B) antibiotics to 23S rRNA, thereby confer the antibiotic resistance on micro-organisms ranging from antibiotic producers to pathogens and are classified into monomethyltransferase and dimethyltransferase. To investigate the differences between mono- and dimethyltransferase, tirD, a representative monomethylase gene was cloned in Escherichia coli from Streptomyces fradiae which contains ermSF, dimethylase gene as well to overexpress the TlrD for the first time. T7 promoter driven expression system successfully overexpress tlrD as a insoluble aggregate at $37^{\circ}C$ accumulating to around 55% of the total cell protein but unlike ErmSF, culturing at temperature as low as $18^{\circ}C$ did not make insoluble aggregate of protein into soluble protein. Coexpression of Thioredoxin and GroESL, chaperone was not helpful in turning into soluble protein either as in case of ErmSF. These results might suggest that differences between mono- and dimethylase could be investigated on the basis of the characteristics of protein structure. However, a very small amount of soluble protein which could not be detected by SDS-PAGE conferred antibiotic resistance on E. coli as in ErmSF which was expected from the activity exerted by monmethylase in a cell.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.2
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• pp.109-114
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• 2021

The characteristics of vibrational stress (shock and vibration) during transport and the possibility of damage to the packaged pears by functional PLA tray were investigated. And this study was conducted to analyze how environmental conditions by simulated transport environment affect quality factors such as weight loss (%) and soluble solid content (SSC, %), and firmness (bioyield strength, kPa) of packaged pears by PLA tray and Expanded PET foam pad (Group 1), EPE cushion cup pad and net (Group 2) for exporting. Pears with or without vibration stress were stored for 30 days at low temperatures (5 ± 0.8℃, 80 ± 5% relative humidity). There was the statistically significant difference (p ≤ 0.05) between pears with and without vibration stress for weight loss, soluble solid content, and firmness (bioyield strength) after 30 days storage. Vibration stress accelerated pear quality deterioration during storage, resulting in increased weight loss, soluble solids content, and reduced hardness. The firmness (bioyield strength) and weight changes of pears with PLA trays were smaller than those of conventional packaging box systems. It was determined that the firmness of agricultural products was a quality factor closely related to the storage period and that PLA could be applied.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1278-1288
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• 2023

Hesperidin(HD) is a a potent antioxidant flavonoid found in various plants. In this study, the recovery of cell death, anti-inflammatory, and melanogenesis inhibitory activities of Hesperidin glucoside (HDG), a water-soluble HD, were compared with HD in vitro. HDG was prepared by an enzymatic glycosylation reaction from HD, and the water solubility of HDG was increased by more than 20,000 times compared to HD. Cell toxicity was significantly lower for HDG than HD. Both HD and HDG increase cell viability in UV damaged HaCaT cells. HD and HDG also reduced an inflammatory mediator such as nitric oxide (NO), and pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the cells irradiated with UV, and the reducing effect of HDG was slightly higher than that of HD. In the melanogenesis inhibition assay using the Melanoma B16F10 cells, HDG showed a superior inhibitory activity compared to HD. In conclusion, HDG, a glucosylated product of HD with high water solubility showed more than equal ability of cell recovery and anti-inflammatory potential, and higher melanogenesis inhibition activity compared to HD in vitro.