Daegu Technical College

Daegu, South Korea

Daegu Technical College

Daegu, South Korea

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Kim J.H.,Korea University | Lee H.-J.,Korea University | Park Y.,Korea University | Ra K.S.,Daegu Technical College | And 3 more authors.
LWT - Food Science and Technology | Year: 2013

The present study describes the use of polysaccharide degrading enzymes (Celluclast 1.5 L, Cytolase PCL5, Spezyme Prime, Econase CE, Optidex L-400, Pectinex 5XL, Rapidase TF, Ultraflo L, and Viscozyme L) to remove pectic mucilage from cactus cladodes to improve extraction and recovery of its components. The cactus cladode homogenate treated with a mixture of Rapidase and Viscozyme (1:3, v/v) showed the lowest viscosity and highest levels of total sugars and polyphenols. After enzymatic hydrolysis, quercitrin content decreased from 66.20 μg mL-1 to 18.76 μg mL-1 and quercetin and isorhamnetin contents increased from 23.24 to 23.18 μg mL-1 to 45.44 and 244.23 μg mL-1, respectively. The increases in isorhamnetin and quercetin aglycon content contributed to increase radical scavenging activity in the cactus hydrolysate after enzyme hydrolysis. The cactus hydrolysis was effective for reducing viscosity and increasing active components and radical scavenging activity. This standard process for removing mucilage from cactus should be available to extend cactus extract applications. © 2012 Elsevier Ltd.


Choi J.W.,Daegu University | Ra K.S.,Daegu Technical College | Kim S.Y.,Korea University | Yoon T.J.,Yuhan University | And 4 more authors.
Bioresource Technology | Year: 2010

To investigate the optimal conditions for the production of Cordyceps sinensis by the submerged culture method, glucosamine and exopolysaccharide (EPS) productivities were determined in culture broth containing different carbon sources, principally rice bran and citrus peel. An optimal medium composition (1.5% rice bran, 0.5% molasses, 3% CSL, 0.1% KH2PO4, and 0.05% MgSO4) and the optimal condition (25 °C and 5-6 d culture time) for high EPS productivity with potent immune-stimulating activities were obtained. The addition of citrus peel to the culture of C. sinensis under the optimized conditions improved EPS productivity and glucosamine content. Furthermore, anti-complementary activity was higher (58.0-80.8%) using citrus peel as compared to no addition of citrus peel (48.2-68.7%). Antioxidant activity (AEAC value) of the citrus peel culture was high (284.3-384.6 mg/100 g) compared to that of the culture without citrus peel (142.8-219.5 mg/100 g), indicating that the citrus peel helped enhance the anti-complementary and antioxidant activities of C. sinensis. © 2010 Elsevier Ltd. All rights reserved.


Kim B.-G.,Yonsei University | Shin K.-S.,Kyonggi University | Yoon T.J.,Yuhan University | Yu K.-W.,Korea University | And 4 more authors.
Applied Biochemistry and Biotechnology | Year: 2011

We investigated ginsenoside transformation by fermentation of red ginseng with Lactobacillus plantarum M-2. We also examined the anti-metastasis and immune-stimulating activities of EtOH extracts of fermented red ginseng (FRG-E) in animal and human subjects. Total sugar decreased from 85.5 mg mL -1 to 44.1 mg mL -1 with increasing culture time during the fermentation with L. plantarum M-2. Uronic acid content reached a maximum level (534.3 μg mL -1) at 3 days of fermentation and decreased thereafter. Ginsenoside metabolites increased from 4,637.0 to 7,581.1 μg mL -1 after 4 days. The prophylactic intraperitoneal injection of FRG-E (500 μg mouse -1) inhibited lung metastasis about 81.1%, while the inhibitory effect against tumor metastasis by treatment of EtOH extract from non-fermented red ginseng (NFRG-E) was 66.9%. Immunoglobulin A (IgA) and G (IgG) levels in the serum of healthy subjects were higher after FRG-E administration than at baseline, whereas NFRG-E induced reductions of these variables related to immunity. At 1 week, the change in IgA level by FRG-E (5.14 mg mL -1) was significantly higher than that by NFRG-E (-14.50 mg mL -1; p<0.05). It was concluded that the immunological activities of FRG-E were higher than those of NFRG-E, indicating that fermentation helped enhance the immunological activities of red ginseng. © 2011 Springer Science+Business Media, LLC.


Joo H.-S.,C and J Biotech | Ra K.S.,Daegu Technical College | Park H.S.,Catholic University of Daegu | Choi J.W.,Daegu University
Biotechnology and Bioprocess Engineering | Year: 2013

Full-length cDNA encoding a fibrinolytic protease (PLFP) from the cDNA library of the polychaete, Periserrula leucophryna was cloned, sequenced and expressed in Escherichia coli. The entire cDNA of the PLFP clone was 921 bp (CDS: 41-837), including a coding nucleotide sequence of 798 bp, a 5′-untranslaed region of 40 bp, and a 3′-noncoding region of 83 bp. The ORF encoded a 265-amino acid polypeptide precursor consisting of a 36-residue signal sequence and a 229-residue mature polypeptide. The sequence alignment results of PLFP revealed sequence similarity with several fibrinolytic enzymes. Sequence analysis revealed a conserved catalytic triad of His78, Asp126 and Ser219 residues, suggesting that PLFP is a serine protease. Mature PLFP had an apparent molecular weight of approximately 25 kDa and was produced in inclusion bodies when expressed in E. coli. Substrate specificity results that recombinant PLFP was active towards Arg-X or Lys-X and did not hydrolyze substrates with nonpolar amino acids at the P1 site. Recombinant PLFP was strongly inhibited by typical serine protease inhibitors, further indicating that PLFP is a member of the serine protease family. PLFP was able to dissolve artificial plasminogenfree fibrin, and its fibrinolytic behavior was similar to that of plasmin. Taken these results together, PLFP is a new member of the fibrinolytic enzyme family with selective specificity on fibrin, and the availability of PLFP offers an attractive alternative approach for thrombolysis therapy because rPLFP is believed to have advantages over currently used plasminogen activators, that is, lower price and lower side effect. © 2013 The Korean Society for Biotechnology and Bioengineering and Springer-Verlag Berlin Heidelberg.


Bae S.H.,Hankyong National University | Choi J.W.,Daegu University | Ra K.S.,Daegu Technical College | Yu K.-W.,Korea University | And 3 more authors.
Journal of the Science of Food and Agriculture | Year: 2012

Background: Makgeolli brewed from rice contains about 150 g kg -1 alcohol and has a fragrance as well as an acidic and sweet taste. During the brewing process, by-products such as rice bran and brewery cake are produced. At the end of fermentation the matured mash is transferred to a filter cloth and the Makgeolli is squeezed out from the cake, leaving the lees of the mash. These by-products have continued to increase every year, resulting in an ecological problem. It is therefore important to develop new uses for them. The objective of this study was to use the by-products from the brewing of Makgeolli as a valuable functional food or nutraceutical. Results: The anti-complementary activities of crude polysaccharides isolated from Cytolase hydrolysates of Makgeolli lees at concentrations of 1000 and 500 μg mL -1 were 84.15 and 78.70% respectively. The activity of polysaccharide krestin (PSK) was 60.00% at 1000 μg mL -1. The active polysaccharide obtained with Cytolase comprised mainly glucose and mannose (molar ratio 1.00:0.62). Conclusion: Glucose- and mannose-rich crude polysaccharides were isolated from the Cytolase hydrolysate of Makgeolli lees. The polysaccharides retain anti-complementary activity to enhance the immune system as a functional food or nutraceutical. © 2011 Society of Chemical Industry.


Bon K.,Daegu University | Suh H.J.,Korea University | Ra K.S.,Daegu Technical College | Choi J.W.,Daegu University
Journal of Microbiology and Biotechnology | Year: 2011

Cyclo(His-Pro) (CHP) is a naturally occurring, cyclic dipeptide structurally related to thyrotropin-releasing hormone (TRH). CHP was efficiently obtained from soybean meal by hydrolysis with flavourzyme and alcalase. In this study, the effects of CHP on streptozotocin (STZ)-induced β-cell dysfunction and apoptosis were investigated in rat insulinoma cells (RINm5F) secreting insulin. When the RINm5F cells were treated with 2mM STZ, insulin secretion decreased to approximately 54% that of control cells. However, CHP treatment restored the insulin-secreting activity of RINm5F cells to approximately 71% that of the untreated control cells. Moreover, CHP significantly protected the cells from STZ-mediated cytotoxicity via reduction of nitric oxide (NO) production (2.3-fold) and lipid peroxidation (1.9-fold), which were induced by STZ. Moreover, CHP treatment also attenuated STZ-induced apoptotic events, such as activation of caspase-3, poly(ADP-ribose) polymerase (PARP) cleavage, and DNA fragmentation in RINm5F cells, indicating that CHP could protect the cells from apoptotic cell death induced by oxidative stress of STZ by increasing the expression of an anti-apoptotic protein, Bcl-2. These results suggest that CHP could be a candidate material for a protective and therapeutic agent against STZ-mediated cytotoxicity and apoptosis © 2009 by the Korean Society for Microbiology and Biotechnology.


Ra K.S.,Daegu Technical College | Suh H.J.,Korea University | Choi J.W.,Daegu University
Biotechnology and Bioprocess Engineering | Year: 2012

The effects of Cyclo (His-Pro) (CHP), a cyclic dipeptide structurally related to thyrotropin-releasing hormone (TRH), on glucose metabolism, blood insulin level, lipid profile, and the viability of pancreatic cells were investigated in streptozotocin (STZ)-induced diabetic rats. The rats (Sprague-Dawley) with a blood glucose level above 300 mg/dL after induction with STZ (50 mg/kg of body weight) were considered to be diabetic and used for the treatment with CHP (4 mg/day/kg of body weight). The blood glucose level in the CHP-fed rats was reduced remarkably by approximately 56% as compared to the untreated diabetic group at 21 days of feeding. In an oral glucose tolerance test, blood glucose levels were restoredto baseline at 120 min after CHP treatment, although the levels increased significantly after 30 min. Plasma insulin levels in the CHP-treated group were also enhanced by 2-fold compared to the untreated group. Triglyceride and total cholesterol levels in CHP-treated rats almost returned to normal levels. Moreover, histological examination showed that CHP treatment restored impaired β-cells in the pancreas up to two-thirds of the normal level. The transcriptional level of C-reactive protein (CRP), used mainly as a marker of inflammation, was also restored mimicking normal level in the CHP-treated-group, suggesting that the β-cells destroyed by STZ were, at least in part, recovered. Accordingly, CHP was concluded to have an excellent hypoglycemic effect by lowering average plasma glucose levels, increasing insulin secretion, and restoring the viability of pancreatic β-cells in diabetic rats. We suggest that CHP might be a potential candidate to control Type I diabetes mellitus. © 2012 The Korean Society for Biotechnology and Bioengineering and Springer.


Lee H.J.,Korea University | Lee H.-S.,Korea University | Choi J.W.,Daegu University | Ra K.S.,Daegu Technical College | And 2 more authors.
Journal of Agricultural and Food Chemistry | Year: 2011

Active compounds with antidiabetic potential were isolated from silk peptide E5K6 by consecutive ultrafiltration and gel filtration using Biogel P-2 and RS-HPLC using a YMC-Pack Pro C18 column. The highest α-glucosidase inhibitory activity of silk peptide E5K6 resulted from fractions with MW <1 kDa. The activities of gel-filtered fractions from silk peptide E5K6 of <1 kDa were assayed in vitro, demonstrating that the fourth peak (F4) had the highest α-glucosidase inhibitory activity (IC 50 = 37.1 mg/mL). F4 of silk peptide E5K6 was separated by HPLC into two peaks. Moreover, the purified compounds were identified as Gly-Glu-Tyr (GEY, MW = 367 Da) and Gly-Tyr-Gly (GYG, MW = 295 Da) according to amino acid sequences, and their α-glucosidase inhibitory activities (IC 50) were 2.7 and 1.5 mg/mL, respectively. © 2011 American Chemical Society.


Han J.H.,Korea University | Choi H.-S.,Korea University | Ra K.S.,Daegu Technical College | Chung S.,KC Feed Co. | Suh H.J.,Korea University
Journal of the Korean Society of Food Science and Nutrition | Year: 2014

In this study, we examined the ionization rate and permeability of nanocalcium prepared from oyster shells with various particle sizes. Four particle sizes of the calcium samples were prepared by centrifugation according to their density disparity in alcoholic solution: NC (normal calcium), C-1 (supernatant of 1,000 rpm), C-2 (supernatant of 2,000 rpm), and C-3 (supernatant of 3,000 rpm). Particle sizes of NC, C-1, C-2, and C-3 were 2,280.3±64.3 nm, 521.3±83.3 nm, 313.9±29.5 nm, and 280.0±3.4 nm, respectively. C-3 showed a slight increase in ionization rate compared with the other calcium samples, but their differences were not significant. Dialysis membrane-employed analysis showed that nanocalcium permeability increased as its particle size smaller; 32% of C-3 nanocalcium was transported to the outside of the membrane, whereas C-1 showed a 25% transport rate. We determined the permeability of the nanocalciums by using rat intestinal sacs, in order to provide different intestinal environments depending on pH level. Nanocalcium generally showed a higher permeability at pH 7, which represents an ileum environments compared to the duodenum and jejunum environments at pH 4.2 and pH 6.2, respectively. However, C-3 calcium showed the highest permeability, followed by C-2, C-1 and NS calciums. This result shows that the size of calcium positively affected its permeability in the intestinal sac. Taken together, nano-sized calcium derived from discarded oyster shell shows improved permeability in intestinal environments.


Moon Y.-H.,Kyungsung University | Jung I.-C.,Daegu Technical College
Journal of the Korean Society of Food Science and Nutrition | Year: 2011

TMR (total mixed ration) feed was developed by adding mugwort (Artemisia capillaris Thunb.) and was fed to Hanwoo cattle. We investigated the effects of feeding mugwort on the physicochemical properties and sensory scores of the Hanwoo beef, as well as the feasibility of producing beef with high quality and function. Samples included Hanwoo loin fed with fattening cattle TMR feed with (treatment) or without mugwort (control). The content of total catechin in Hanwoo loin fed with the treatment and control was 0.516 and 0.307 mg/kg, respectively, while the content of epicatechin was 0.116 and 0.087 mg/kg, respectively, both of which were significant increase from feeding TMR with mugwort (p<0.05). There was no significant difference between the control and treatment in terms of b* value, VBN content, EDA, total bacterial numbers, freezing loss, thawing loss, cooking loss, hardness, cohesiveness, gumminess, chewiness, shear force, or sensory score of boiled meat. L*, a* and pH value for the treatment were significantly higher than the control (p<0.05). TBARS and springiness for the control were significantly higher than the treatment (p<0.05). The aroma of the raw meat and the taste, tenderness, juiciness, and palatability of the roasted meat for the treatment were significantly superior to the control (p<0.05). These results suggest that giving feed containing mugwort inhibits lipid oxidation, increases water holding capacity, and improve sensory scores.

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