• Applied Biological Chemistry
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• v.33 no.1
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• pp.8-13
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• 1990

The solid and protein yields and extraction properties of color pigments were compared for 7 varieties of soybeans during soaking in water at $4-100^{\circ}C$. The varieties investigated were Paldal, Danyeob, Jangbaek, Baegun, Jangyeob and 2 cultivars of Local 1 and Local 2. The Hunter values showed that Jangbaek was the highest in 'L' value while other varieties except Local 1 and Local 2 were comparatively high in 'L' value. Local 1 and Local 2 were low in 'b' value. The yields of solid and protein during water extraction showed that most of solids and proteins were recovered with three consecutive extractions. The cumulated yields were 73.2 % for solid and 83.2 % for protein. Extraction of color pigments of seed coats in $4-100^{\circ}C$ water showed that the extraction rate was very much dependent on extraction time and temperature. A linear relationship of A=aT+b was obtained for equilibrated absorbance(A) and extraction temperature(T). The activation energy calculated from initial extraction rate of cole. pigments and temperature had two different values of low($4-60^{\circ}C$) and high($60-100^{\circ}C$) temperature range.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.387-392
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• 1992

In order to improve the solids and protein concentration and their yields in sea mustard extracts, HCl, sucrose, NaCl, EDTA, and SHMP were added during aqueous extraction and studied their effects on quality characteristics of the extracts. The extracts were prepared by 2 hours of boiling of ground sea mustard and centrifugation. Addition of HCl at $0.1{\sim}0.5N$ level was found that the solids and protein yields was significantly improved along with the ratio of supernatant seperated. The maximum solids and protein yields obtained were 52.48%, 36.73%, respectively, while those values of the aqueous extract without HCl were 23.20%, and 4.87%. Viscosity was reduced from 450 cps to less than 20 cps by HCl addition. When NaCl, sucrose, SHMP, and $Na_2EDTA$ were added in the concentration of range of $0.5{\sim}3.0%$, solid concentration and yields were also significantly improved by the order of $Na_2EDTA-SHMP-sucrose-NaCl$ in their effect. The highest solid yield of 55.0% was obtained from 3% addition of $Na_2EDTA$. Viscosity and turbidity were also reduced by addition of SHMP and $Na_2EDTA$.

• KSBB Journal
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• v.18 no.6
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• pp.500-505
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• 2003

‘LK (lipoprotein kringle) 68’is a polypeptide of a modified ansiostatin consisting of three kringle structures that might be clinically useful as a potential cancer therapeutics. It can be produced by overexpressing it as inclusion body in recombinant E. coli. In this study, solid-phase refolding processes using packed bed adsorption (PBA) and expanded bed adsorption (EBA) column were carried out to compare their refolding yields with that of the conventional, solution-phase refolding process, For the solution-phase and the PBA-mediated processes employing Q-Sepharose, washed inclusion body was used as the starting material, whereas both washed inclusion body and E. coli homogenate were used for the EBA-mediated process employing streamline DEAE. On the final recovery LK68 per unit mass of wet cell basis, the EBA- and PBA-mediated processes showed about 2.7- and 1.5-fold higher yields, respectively, than the solution-phase refolding method. The solid-phase refolded LK68 demonstrated the same Iysine binding bioactivity and the retention time in the RP-and SEC-HPLC as those of the native protein.

• Journal of the Korean Magnetic Resonance Society
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• v.18 no.2
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• pp.58-62
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• 2014

Human transmembrane proteins (hTMPs) are closely related to transport, channel formation, signaling, cell to cell interaction, so they are the crucial target of modern medicinal drugs. In order to study the structure and function of these hTMPs, it is important to prepare reasonable amounts of proteins. However, their preparation is seriously difficult and time-consuming due to insufficient yields and low solubility of hTMPs. We tried to produce large amounts of Syndecan-4 transmembrane domain (Syd4-TM) that is related to the healing wounds and tumor for a long time. In this study, we performed the structure determination of Syd4-TM combining the Polarity Index at Slanted Angle (PISA) wheel pattern analysis based on $^{15}N-^1H$ 2D SAMPI-4 solid-state NMR of expressed Syd4-TM and Molecular Dynamics (MD) simulation using Discovery Studio 3.1.

• KSBB Journal
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• v.16 no.2
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• pp.146-152
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• 2001

To avoid the intrinsic problem of aggregation associated with the traditional solution-phase refolding process, we propose a solid-phase refolding method integrated with expanded bed adsorption chromatography. The model protein used was a fusion protein of recombinant human growth hormone and a glutathione S transferase fragment. It was demonstrated that the EBA-mediated refolding technique could simultaneously remove cellular debris and directly renature the fusion protein inclusion bodies in the cell homogenate with much higher yields and less agregation. To demonstrate the applicability of the method, we successfully tested the three representative types of starting materials, i. e., rhGH monomer, washed inclusion bodies, and the E. coli homogenate. This direct and simplified refolding process could also reduce the number of renaturation steps required and allow refolding at a higher concentration, at approximately 2 mg fusion protein per ml of resin. To the best of our knowledge, it is the first approach that has combined the solid-phase refolding method with expanded bed chromatography.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.433-440
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• 1988

Dried anchovy (Engraulis japonica) was ground and treated with 0.3N NaOH solution and then hydrolyzed with proteolytic enzymes. Extracts obtained by centrifugation of alkali-enzyme treated anchovy slurry was compared with water extract for the yields of soluble solid, protein and ashes and organoleptic characteristics. The data for the yields of the soluble solids, protein and ash showed that a 2-3 folds increase in those yields was resulted by combined alkali-enzyme treatments when it was compared to water only extract. The organoleptic evaluation on the alkali-enzyme treated anchovy extracts also showed a 2-3 folds in flavor strength of all descriptions in odor and taste and a significant improvement in total odor or taste acceptability.

• BMB Reports
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• v.41 no.3
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• pp.194-203
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• 2008

Nitrosative modifications regulate cellular signal transduction and pathogenesis of inflammatory responses and neuro-degenerative diseases. Protein tyrosine nitration is a biomarker of oxidative stress and also influences protein structure and function. Recent advances in mass spectrometry have made it possible to identify modified proteins and specific modified amino acid residues. For analysis of nitrated peptides with low yields or only a subset of peptides, affinity 'tags' can be bait for 'fishing out' target analytes from complex mixtures. These tagged peptides are then extracted to a solid phase, followed by mass analysis. In this review, we focus on protein tyrosine modifications caused by nitrosative stresses and proteomic methods for selective enrichment and identification of nitrosative protein modifications.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.382-386
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• 1992

Effect of temperature on some quality characteristics of aqueous extracts of sea mustard was investigated. The concentration of total solids and protein and their yields in the extracts were increased as the extraction temperature raised from $50^{\circ}C$ to $100^{\circ}C$ during initial period of extraction. However the lower values of the percent of supernatant was obtained at $50^{\circ}C$ and $100^{\circ}C$. The percent of yields of solids and protein for 1 hour extraction at $100^{\circ}C$ were 21.56% and 4.7%, respectively. The highest viscosity, which was $2.5{\sim}4.0$ times of higher values of the other extracts, was obtained by 2 hours extraction at $100^{\circ}C$. The turbidity was gradually decreased after 1 hour extraction. The activation energy calculated for initial increase rate of solid and protein concentration were 1.18 and 3.90 Cal/mole, respectively.

• KSBB Journal
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• v.18 no.4
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• pp.306-311
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• 2003

Solid-phase refolding of immobilized proteins can be an effective way to reuse an immobilized enzyme column. Oriented immobilization methods are known to provide higher activity of the immobilized enzymes. In this study, using recombinant EK (enterokinase) as a model enzyme and a fusion protein, that consisted of recombinant human growth hormone and six His tag that was linked by the peptide of EK-specific recognition sequence, as a model substrate, we evaluated two oriented immobilization methods, i. e., reductive alkylation of N-terminus ${\alpha}$-amine and affinity interaction between poly-histidine tag and Ni-NTA (nickel-nitrilotriacetic acid). The immobilization yield, activity and cleavage of the immobilized enzymes, and the yield of solid-phase refolding were compared. The Ni affinity immobilization and the covalent immobilization yields were about 100％ and 65％, respectively. But the specific activities were the same, about 50％ of that of the soluble enzyme. The cleavage rate by the covalently immobilized EK was higher than the soluble enzyme and the side reaction of cryptic cleavage was significantly decreased. Covalently immobilized EK showed almost 100％ refolding yield but the affinity immobilized EK showed only 70％ yield, which suggested the covalent conjugation provided more rigid ‘reference structure’ for the solid-phase refolding. The monomeric hGH could be easily obtained by capturing the cleaved poly Histidine tag by the Ni affinity column.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.184-189
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• 1994

The possibility of solid-substrate fermentation of Coriolus versicolor for the production of protein-bound polysaccharides(PBP) was studied. Zeolite and orchid-pot soil were used as solid materials for the culture because of the desirable physical properties. Glucose, sucrose and starch showed to be good carbon sources for the production of PBP by the solid-substrate fermantation of C. versicolor. Among the nitrogen sources, bactosoyton and peptone were very effective for the PBP production. The optimum pH for solid-substrate culture for the production of PBP was at the range of 5-6. The yields of PBP reached to 5-6 mg per 100 g solid-substrate.