• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.33 no.3
• /
• pp.198-204
• /
• 2000

In order to utilize by-products which would normally be discarded in marine processing plants, cod teiset protein was hydrolyzed and antioxidative actiTity of the hydrolysate was investigated. AntioxidatiTe peptide was isolated using ultrafiltration membrane, ion-exchange chromatography on a SP-Sephadex C-25 column, gel filtration on a Sephadex G-15 column, high performance liquid chromatography on an ODS column, and capillary electrophoresis chromatography. Antioxidative activities of the cod teiset hydrolysate were compared with ${\alpha}-tocopherol$, one of the commercial antioxidant. The hydrolysate passed through a membrane with molecular weight cut-off (MWCO) 1 kDa was shown the strongest antioxidative activity, and the activity was higher $10{\%}$ as compared with ${\alpha}-tocopherol$. In addition, the peptide isolated by ion-exchange chromatography, gel filtration, and HPLC, respectively, was higher $53{\%}$ as compared with ${\alpha}-tocopherol$, and the amino acid sequence was Ser-Asn-Pro-Glu-Trp-Ser-Trp-Asn.

• Reproductive and Developmental Biology
• /
• v.35 no.3
• /
• pp.265-271
• /
• 2011

This study was undertaken to find out the effect of methyl-beta-cyclodextrin (MBCD) on cold shock and membrane cholesterol quantity of sperm during the freezing process in miniature pigs. For this study, semen ejaculated from PWG M-type miniature pig was diluted that freezing solution (with egg yolk group) and m-Modena B (without egg yolk group) treated with 0, 1, 5, 10 and 20 mM MBCD before freezing process. The diluted semen was monitored sperm ability at room temperature, after cooled until $5^{\circ}C$ and after forzen-thawed for cold shock test of spermatozoa. Also, membrane cholesterol of sperm was extracted by folch solution at the same time sperm ability was assessed for viability and acrosomal status. The membrane cholesterol quantity was measured by thin-layer chromatography (TLC) method. The result, viability and acrosome integrity in semen diluted without egg yolk groups were decreased at all temperature range by increasing of MBCD concentration. In particular, sperm of egg yolk group was showed that significantly higher viability and lower acrosome damage when treated with 5 mM MBCD (p<0.05). The results of TLC experiment, cholesterol amounts were increased with MBCD cocentration in egg yolk, and decreased with MBCD concentration in m-Modena B. In cryopreservation efficiency, there was no significant difference at viability, and acrosomal state of sperm in 5 mM MBCD concentration was significantly lower in acrosome damage than other groups (p<0.05). Therefore, the addition MBCD in egg yolk was protected spermatozoa from cold shock injury. This protective effect of MBCD may be due to addition of sperm membrane cholesterol.

• BMB Reports
• /
• v.39 no.5
• /
• pp.516-521
• /
• 2006

Modifications in dietary fatty acid intake might lead to a modification in membrane phospholipid fatty acid composition. The purpose of this study was to investigate relationship between different type of oil consumption and leukocyte membrane phospholipid composition. This study was carried out in subjects utilizing butter (n = 15), margarine (n = 15), fluid oil (n = 15) and mixed types of oils (n = 15) in total 60 subjects. Leukocytes were separated from total blood by dextran sedimentation method. Membrane lipids and proteins were isolated following the cell disruption. Fatty acids of membrane phospholipids were isolated by hydrolysation with phospholipase B under ultrasonic dismembranator. Free fatty acids were identified with gas chromatography at chloroform phase. The results obtained were compared with data obtained by chromatograms of the standards. Results more prominent values of arachidic, dihomo-$\gamma$-linolenic and palmitoleic acids were found in butter-or mixed oil-user groups; eicosadienoic, eicosamonoenoic, dihomo-$\gamma$-linolenic and behenic acids in fluid oil; heptanoic, valeric, eicosadienoic and linolenic acids in margarine groups. The fatty acid composition of mixed oil was similar to butter, while other two oils were so different. From this study, it was concluded that the type of oil consumption might have an influence on phospholipid components of plasma membranes.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.8
• /
• pp.1299-1306
• /
• 2015

This study aims to investigate the mechanism of action of the cinnamon bark essential oil (CB), when used singly and also in combination with piperacillin, for its antimicrobial and synergistic activity against beta-lactamase TEM-1 plasmid-conferred Escherichia coli J53 R1. Viable count of bacteria for this combination of essential oil and antibiotic showed a complete killing profile at 20 h and further confirmed its synergistic effect by reducing the bacteria cell numbers. Analysis on the stability of treated cultures for cell membrane permeability by CB when tested against sodium dodecyl sulfate revealed that the bacterial cell membrane was disrupted by the essential oil. Scanning electron microscopy observation and bacterial surface charge measurement also revealed that CB causes irreversible membrane damage and reduces the bacterial surface charge. In addition, bioluminescence expression of Escherichia coli [pSB1075] and E. coli [pSB401] by CB showed reduction, indicating the possibility of the presence of quorum sensing (QS) inhibitors. Gas-chromatography and mass spectrometry of the essential oil of Cinnamomum verum showed that trans-cinnamaldehyde (72.81%), benzyl alcohol (12.5%), and eugenol (6.57%) were the major components in the essential oil. From this study, CB has the potential to reverse E. coli J53 R1 resistance to piperacillin through two pathways; modification in the permeability of the outer membrane or bacterial QS inhibition.

• Korean Journal of Food Science and Technology
• /
• v.31 no.2
• /
• pp.458-464
• /
• 1999

The value of lysozyme as a natural food preservative is continuously increased due to its unique antimicrobial activity. To determine the optimum separation concentration among the various hen egg white protein (HEWP) concentrations (0.25, 0.5, 1.0, w/v), protein concentrations, lysozyme concentrations, specific activities (SA), and purification factors of prefiltered solution (PFS) and PM30 permeate solution (PMS) were compared. The purity of lysozyme separated at each step was analyzed and confirmed by gel permeation chromatography and electrophoresis. The fouling deposits on membrane were observed by SEM. The non-enzymatic proteins were removed over 99% by ultrafiltration (UF). The increased feed concentration did not contribute to the increase of SA. SA of PMS was 18 to 31 times higher than that of PFS. The optimum feed concentration was decided as 0.25% based on SA and purification factor. The non-enzymatic region of gel chromatogram was proved to be ovalbumin. The thickness of deposit on the UF membrane was approximately $0.9{\mu}m$ and removed by cleaning with 0.1 N NaOH. Therefore, UF using PM30 membrane was very effective to separate the antimicrobial lysozyme from various HEWPs.

• KSBB Journal
• /
• v.18 no.3
• /
• pp.190-196
• /
• 2003

An analytical system detecting DNA particularly utilizing a concept of membrane strip chromatography initially applied to home-version tests for, such as, pregnancy and ovulation has been developed. We have chosen S. typhimurium as model analyte among food-contaminating microorganisms that occurred in high frequencies, and invA gene, as a detection target, specific to Salmonella species. This gene was able to be amplified by PCR under optimal conditions employing newly designed primers in our laboratory. The PCR product was specifically measured via hybridization between the analyte and a DNA probe, which was a totally different feature from the conventional gel electrophoresis detecting the products based only on the molecular size. It is notable thar the DNA probe sequence was specially designed such that no separation of excess primers present after PCR was required. This was immobilized on a nitrocellulose (NC) membrane via streptavidin-biotin linkage minimizing a steric effect when the hybridization with the amplified DNA took place. The analyrical system detected the microorganism in a concentration of minimum $10^3$ cfu/mL (i.e., 10 cells per system), estimated from the standard curve, 20 to 40 minutes after adding the sample. This sneitivity was approximately 10 times higher than that of gel electrophoresis as an analytical tool conventionally used. Furthermore, the assay was able to be run at room temperature, which would ofter an extra advantage to users.

• KSBB Journal
• /
• v.14 no.5
• /
• pp.528-533
• /
• 1999

Membrane-bound alcohol dehydrogenase(ADH) was purified to homogeneity from the acetic acid producing bacteria, Acetobacter sp. CS5. The enzyme was solubilized and extracted with Trition-X and purified using the DEAE-Sephacel chromatography and Sephacryl S-200 chromatography. The enzyme was purified to 14-fold with a yield of 15%. The molecular weight of the purified enzyme was to be 332 KDa. SDS-PAGE of the enzyme showed three subunits with molecular weights of 79 KDa, 49KDa and 46K Da. It indicated that enzyme consisted of three subunits of the 79 KDa, two subunits of the 49 KDa and. 46 KDa, respectively. The apparent Km value for ethanol was 0.77 mM and the optimum pH and temperature was 4.0-5.0 and 35$^{\circ}C$, respectively.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.6
• /
• pp.929-935
• /
• 2007

The objective of this study was to develop a rapid, simple, and qualitative acetylcholinesterase (AChE)- detection kit, based on a modification of the Ellman and ELISA methods, for the detection of organophosphorus (OP) and carbamate (CB) pesticide. The developed kits were used to screen a large number of agricultural samples (spiked and real) for OP and CB pesticide residues. AChE was extracted from the heads of honeybees (Apis mellifera L.) using Triton X-100, and was purified through 3 steps: diethylaminoethylcellulose chromatography (DEAE), affinity chromatography and membrane filtering, and Mono-Q column chromatography. Epoxy-activated Sepharose 6B affinity chromatography was used for large-scale purification. The presence of OP and CB pesticide residues in agricultural samples was assayed on the basis of AchE inhibition value. The presence (6 bands) or absence of some colored bands on the test line indicated a negative or positive result, respectively. The limits of detection for measured organophosphorus (OP) and carbamates (CB) pesticide residues in standard pesticide solutions and fortified samples were ranged from 0.50 to 2.50 ppm and 0.50 to 4.75 ppm, respectively.

• Journal of the Korean Magnetic Resonance Society
• /
• v.16 no.1
• /
• pp.34-45
• /
• 2012

Melanocortin-4 receptor (MC4R) subtype is associated with obese humans. Especially, in a patient with severe early-onset obesity, novel heterozygous mutation in the MC4R gene was detected, resulting in an exchange of aspartic acid to asparagine in $90^{th}$ amino acid residue located in the predicted second trans-membrane domain (TM2). Mutations in the melanocortin-4 receptor (MC4R) gene are the most frequent monogenic causes of severe obesity which have been described as heterozygous with loss of function. In order to compare structure difference between MC4R wild type (MC4R-TM2-wt) and mutant (MC4R-TM2-D90N), we designed both MC4R-TM2-wt and MC4R-TM2-D90N construct in pET 21b vector. In this study, we optimized high-yield purification procedure for recombinant TM2-D90N. Eluted recombinant protein was resolubilized under urea condition for thrombin cleavage reaction and we conducted the high-performance liquid chromatography (HPLC) with reverse phase column under 1% acetonitrile, 0.01% TFA buffer solution. The molecular size of purified target peptide was confirmed by Tricine-SDS page analysis. To characterize MC4R-TM2-D90N, we have performed $^{15}N$-isotope labeling of peptide using M9 media and purified labeled target peptide for hetero-nuclear NMR spectroscopy.

• KSBB Journal
• /
• v.16 no.6
• /
• pp.533-537
• /
• 2001

${\alpha}$-lactalbumin and ${\beta}$-lactoglobulin in whey proteins were separated by high performance membrane chromatography (HPMC). The separation mechanism involved anion-exchange, and the stationary phase was anion CIM (Convective Interaction Media) DEAE, QA disk and cation exchanger SO$_3$(16${\times}$3 mm). Two types of mobile phase were used, buffer A (20 mM Tris-HCI, pH 7.3) and buffer B(buffer A + 1 M NaCl), As the amount of NaCl dissolved in buffer linearly increased, which enabled a gradient elution mode. The optimum mobile phase and operating condition (Buffer A/Buffer B = 100/0 - 30/70 vol%, gradient time 1 min, 30/70 - 10/90 vol.%, gradient time 2 min) were experimentally determined. In this experimental condition, ${\alpha}$-lacta1bumin, ${\beta}$-lactoglobulin were separated within 5 min at a mobile phase flow rate of 4 mL/min.