• JSTS:Journal of Semiconductor Technology and Science
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• v.7 no.3
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• pp.151-160
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• 2007

We report the label-free biomolecules detection based on nanomechanical micro cantilevers operated in dynamic mode for detection of two marker proteins (myoglobin and creatin kinase-MB (CK-MB)) of acute myocardical infarctions. When the specific binding between the antigen and its antibody occurred on the fuctionalized microcantilever surface, mechanical response (i.e. resonant frequency) of microcantilevers was changed in lower frequency range. We performed the label-free biomolecules detection of myoglobin and CK-MB antigen in the low concentration (clinical threshold concentration range) as much as 1 ng/ml from measuring the dynamic response change of micro cantilevers caused by the intermolecular force. Moreover, we estimate the surface stress on the dynamic microcantilevers generated by specific antibody-antigen binding. It is suggested that our dynamic microcantilevers may enable one to use the sensitive label-free biomolecules detection for application to the disease diagnosis system based on mechanical immuno-sensor.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1527-1534
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• 2010

The conventional peptide modification process of guanidination, in which the amino groups of lysine residues are converted to guanidino groups using O-methylisourea to create more basic homoarginine residues, is often used to improve the signal intensity of lysine-containing peptides in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Here, we used three different protease enzymes (trypsin, Lys-C, and Glu-C) to evaluate the effects of guanidination on the MS signals of two enzymatically digested proteins. Horse heart myoglobin and bovine serum albumin were guanidinated either before or after digestion with trypsin, Lys-C, or Glu-C. The resulting peptides were subjected to MALDI-MS, and signal intensities and sequence coverage were systematically evaluated for each digest. Guanidination prior to Glu-C digestion improved sequence coverage for both proteins. For myoglobin, guanidination before enzymatic digestion with trypsin or Lys-C also enhanced sequence coverage, but guanidination after enzymatic digestion enhanced sequence coverage only with Lys-C. For albumin, guanidination either before or after Glu-C digestion increased sequence coverage, whereas pre- or post-digestion guanidination decreased sequence coverage with trypsin and Lys-C. The amino acid composition of a protein appears to be the major factor determining whether guanidination will enhance its MALDI-MS sequence coverage.

• Journal of Animal Science and Technology
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• v.63 no.1
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• pp.160-169
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• 2021

Boiled feed is obtained by mixing and boiling agricultural by-products such as rice straw, rice bran, and bean curd with grains. The study explored the change in fatty acid, free amino acid, nucleotide, mineral, cholesterol, myoglobin and collagen of longissimus dorsi muscle in Hanwoo steers fed with boiled feed. Forty steers, 20 heads per group, were divided into two groups: a control group and a boiled feed group. The steers were raised for 10 months. The boiled feed group was enriched with palmitoleic acid, oleic acid, arachidonic acid and unsaturated fatty acids compared with the control group. There were no significant differences in amino acid and nucleic acid composition between the two groups. The boiled feed group contained higher levels of iron and manganese in the boiled feed group compared with the control group. The total cholesterol level was significantly increased, whereas calorie levels, myoglobin and collagen composition showed no differences. As the supply of boiled feed increases the content of fatty acids, unsaturated fatty acids and minerals related to flavor, it should be a feed that leads to the production of high-quality beef.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.2
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• pp.188-193
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• 2016

This study was conducted to investigate the antioxidant activities of 70% ethanol extracts from different parts (root, stem, and leaf) of Epimedium koreanum Nakai. Ethanol extracts from the three parts of Epimedium koreanum Nakai were assessed for total phenolic content, total flavonoid content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, myoglobin protective ratio, and ferric reducing antioxidant power (FRAP). Root part showed the highest total phenolic content ($2.468{\pm}0.017mg$ chlorogenic acid equivalent/g) and total flavonoid content ($2.071{\pm}0.002mg$ quercetin equivalent/g). Leaf part showed the strongest radical scavenging activities (DPPH radical; 80%, myoglobin protective ratio; 90% and FRAP; 98.7% at 20 mg/mL). Root part showed the highest ABTS radical scavenging at 1 mg/mL. Therefore, the results of the antioxidant activity test were correlated with total phenolic and flavonoid content values. Thus, Epimedium koreanum Nakai has great potential as a natural source for human health.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.177-182
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• 1990

The changes in the partition coefficient of model proteins (lysozyme, myoglobin, conalbumin, bovine serum albumin) in an aqueous two·phase system formed by polyethylene glycol and dextran were examined in order to improve the capacity of counter current distribution (CCD) for the protein fractionation and concentration . The protein distribution pattern in CCD with 30 tubes varied with the pH (4.5, 5.5, 6.5, 9.0, 12.0) and KCl concentration (0mM, 50mM, 250mM, 500mM) of the system. From the mixture of model proteins, pure myoglobin was appeared at the upperphase of 14th tube having 50mM of KCl at pH 5.5 and the upper-phase of 13th tube having 250mM of KCl at pH 6.5. Similarly pure BSA was obtained at the 14th tube having KCl 250mM with pH 4.5, pure lysozyme at the 19th tube having 500mM of KCl at pH 4.5 and the upper-phase of 16th tube 50mM of KCl at pH 5.5.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.4
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• pp.207-211
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• 2004

The purpose of the present study was to evaluate the expression of cardiac marker protein in rabbit cardiac tissue that was exposed to ischemic preconditioning (IPC), or ischemiareperfusion injury (IR) using two-dimensional gel electrophoresis (2DE) and matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). We compared 2DE gels of control (uninjured) cardiac tissue with those of IPC and IR cardiac tissue. Expression of one protein was detected in IR heart tissue, however the protein was not detected in the samples of control and IPC tissue. To further characterize the detected protein molecule, the protein in the 2D gel was isolated and subjected to trypsin digestion, followed by MALDI-MS. The protein was identified as myoglobin, which was confirmed also by Western blot analysis. These results are consistent with previous studies of cardiac markers in ischemic hearts, indicating myoglobin as a suitable marker of myocardial injury. In addition, the present use of multiple techniques indicates that proteomic analysis is an appropriate means to identify cardiac markers in studies of IPC and IR.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.222-227
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• 2002

Efficacy of submersion aging in chilled water of vacuum-packed Hanwoo beef was investigated. At 24 hours post-mortem, the somimemebranosus portion of Hanwoo carcass was excised and sliced (2.5cm, thickness). After beef core samples(6$\textrm{cm}^2$${\times}$2cm) were prepared and vacuum packed, the samples were randomly assigned to the four treatments which were conventional refrigerator at 4$^{\circ}C$(control), conventional refrigerator at 1$^{\circ}C$(T1), submersion in chilled water at 4$^{\circ}C$(T2) and submersion in chilled water at 1$^{\circ}C$(T3). Samples were stored for 3, 7, 10 and 14 days to measure meat color(CIE L*, a*, b*), deoxymyoglobin, oxymyoglobin and metmyoglobin percentage, thiobarbituric acid reactive substance (TBARS) value, purge loss(%) and total heam pigment content. CIE a* value of samples was not significantly changed by treatment during the storage. However, metmyoglobin content of T2 samples was significantly (p<0.05) lower than those of control and T1,T3 during storage. Also, TBARS value of T3 samples was significantly (p<0.05) lower than those of control and T2 samples. T3 showed the lowest purge loss%, whereas control remarked the highest purge loss(%). Total heam pigment of all samples were not significantly changed during the storage. These results suggested that submersion aging in chilled water could keep the myoglobin stability and reduce lipid oxidation and purge loss of vacuum packed beef during storage.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.287-293
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• 2013

This study was conducted to investigate the effect of quality grade on the physicochemical and sensory properties of Hanwoo beef on the basis of four quality grades (grade $1^{{+}{+}}$, $1^{+}$, 1, and 2). Significantly decreased levels of myoglobin content (from 12.73 mg/g to 7.90 mg/g) and Warner-Bratzler shear force (WBs) (from 28.01 kg to 14.03 kg) were found with reduction in quality grade (p<0.05). In contrast, increasing quality grade correlated with significant increase in crude fat contents (from 8.18% to 19.55%). Crude fat contents showed a negative correlation with moisture content (r=-0.966), myoglobin content (r=-0.998), and WBs (r=-0.969). In sensory evaluation experiments it was revealed that quality grades were associated with significantly altered (all p<0.05) flavor, taste, juiciness, tenderness, and overall acceptability. Moisture contents showed negative correlation with taste (r=-0.969) and overall acceptability (r=-0.988). Crude fat contents showed significant correlation with taste (r=0.971), tenderness (r=0.983) and overall acceptability (r=0.968). WBs showed negative correlation with taste (r=-0.957) and overall acceptability (-0.978). The marbling score of fresh meat showed significant correlation with taste (r=0.958), juiciness (r=0.953), and overall acceptance of cooked meat. These results could be used as a fundamental dataset to evaluate the effect of quality grade on the physicochemical and sensory characteristics of Hanwoo beef.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.427-434
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• 2010

This study was conducted to investigate the changes in haem pigments, peroxide value, TBARS, free fatty acid contents and fatty acid composition of five muscles from low fat pork cuts during storage at $4^{\circ}C$ for 14 d. The myoglobin contents (Oxy, Met and Total) did not change significantly (p>0.05) as storage time increased. In addition, the peroxide value did not change significantly (p>0.05), but the thiobarbituric acid reactive substances were significantly (p<0.05) upregulated during chilled storage. The total free fatty acid contents of the longissimus dorsi muscle were significantly (p<0.05) upregulated, but the saturated, unsaturated, mono-unsaturated and poly-unsaturated fatty acid composition of the muscles did not change significantly (p>0.05) during chilled storage.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2003.06a
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• pp.157-157
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• 2003