• Food Science of Animal Resources
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• v.29 no.5
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• pp.633-639
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• 2009

The principal objective of the current study was to prepare low molecular weight peptides from milk proteins using enzymatic hydrolysis techniques, in an effort to assess the antioxidant activity of these peptides. The casein and whey proteins isolated from fresh milk were treated with several proteolytic enzymes, such as chymotrypsin, pepsin, and trypsin and the resulting low molecular weight peptides were collected by TCA precipitation. Their identity was confirmed by SDS-PAGE analysis. The hydrolysis experiments indicated that whey protein treated with chymotrypsin displayed the highest degree of protein hydrolysis. The antioxidant activity of milk protein hydrolysates was determined by measuring the ABTS-radical scavenging activity. The results of these experiments showed that hydrolysis of the milk protein was effective in increasing their antioxidant activities. Especially, the tryptic digested casein displayed the highest radical scavenging activity (80.7%). The hydrolyzed low molecular weight milk protein was isolated using an ultrafiltration membrane. The casein hydrolysate passed through a membrane with molecular weight cut-off (MWCO) of 3 kDa displayed the strongest antioxidant activity.

• Journal of the Korean Magnetic Resonance Society
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• v.25 no.4
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• pp.58-63
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• 2021

Apolipoprotein B-100 (apo B-100), the main protein component that makes up LDL (Low density lipoprotein), consists of 4,536 amino acids and serves to combine with the LDL receptor. The oxidized LDL peptides by malondialdehyde (MDA) or acetylation in vivo act as immunoglobulin (Ig) antigens and peptide groups were classified into 7 peptide groups with subsequent 20 amino acids (P1-P302). The biomimetic peptide P143 (IALDD AKINF NEKLS QLQTY) out of C-group peptides carrying the highest value of IgG antigens were selected for structural studies that may provide antigen specificity. Experimental results show that P143 has β-sheet in Ile[1]-Asn[9] and α-helice in Gln[16]-Tyr[20] structure. Homonuclear 2D-NMR (COSY, TOCSY, NOESY) experiments were carried out for NMR signal assignments and structure determination for P143. On the basis of these completely assigned NMR spectra and proton distance information, distance geometry (DG) and molecular dynamic (MD) were carried out to determine the structures of P143. The proposed structure was selected by comparisons between experimental NOE spectra and back-calculated 2D NOE results from determined structure showing acceptable agreement. The total Root-Mean-Square-Deviation (RMSD) value of P143 obtained upon superposition of all atoms were in the set range. The solution state P143 has a mixed structure of pseudo α-helix and β-turn(Phe[10] to Glu[12]). These results are well consistent with calculated structure from experimental data of NOE spectra. Structural studies based on NMR may contribute to the prevent oxidation studies of atherosclerosis and observed conformational characteristics of apo B-100 in LDL using monoclonal antibodies.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.4
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• pp.321-326
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• 2012

Recent studies have revealed that collagen peptide plays a protective role on skin by improving the activity of antioxidants and acts as an inducer of skin regeneration. To evaluate the efficacy of low molecular weight collagen peptide for skin recovery after non-ablative 1550 nm fractional photothermolysis laser. 10 volunteers were randomly divided into two groups. Both control and experimental groups received fractional photothermolysis treatment. In the experimental group, 5 subjects received oral collagen peptide 1,000 mg/day for 8 weeks. Before and after the treatment, we measured elastic recovery of skin, transepidermal water loss (TEWL) and erythema index (EI) for each patients. The evaluation of clinical results showed that elastic recovery of skin is higher in the experimental group than the control group (p < 0.05). TEWL have no significancy between two groups and erythema rapidly disappeared in the experimental group. On the quartile grading scale, the mean patient satisfaction 4 weeks after the fractional photothermolysis treatment was 2.0 in experimental group and 1.2 in control group. The low molecular weight collagen peptide appears to be an effective conservative therapy for skin recovery after non-ablative 1550 nm fractional photothermolysis treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1124-1129
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• 2005

Functional activities of low molecular weight substances purified from pepsin hydrolysates of four different seaweeds; Costaria costata, Enteromorpha prolifera, Grateloupia filicina and Porphyra tenera, were inves-tigated. Each pepsin hydrolysate of Costaria costata, Enteromorpha prolifera, and Grateloupia filicina resulted in three peptide peaks on Bio-Rad P2 gel chromatography pattern, while that of Porphyra tenera showed 2 peaks. Peak 1 of Porphyra tenera showed the highest antioxidative activity followed by peak 2 of Porphyra tenera and peak 2 of Costaria costata in order Peak 1 of Porphyra tenera showed the highest ACE inhibitory activity followed by peak 3 and peak 2 of Enteromorpha prolifera in order. Peak 1 and peak 2 of Porphyra tenera, and peak 2 of Enteromorpha prolifera showed the highest antityrosinase activity followed by peak 3 of Enteromorpha prolifera. Peak 1 of Enteromorpha prolifera showed the highest antitumor activity followed by peak 2 of Costaria costata, peak 3 of Enteromorpha prolifera, and peak 3 of Grateloupia filicina in order. Porphyra tenera showed the highest functional activities, which is thought to be due to its high protein content. Structure and amino acid sequence of low molecular weight peptide of Porphyra tenera should be analyzed in the further study.

• Journal of Microbiology and Biotechnology
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• v.31 no.10
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• pp.1401-1408
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• 2021

This study examined whether the oral administration of low-molecular-weight collagen peptide (LMCP) containing 3% Gly-Pro-Hyp with >15% tripeptide (Gly-X-Y) content could ameliorate osteoarthritis (OA) progression using a rabbit anterior cruciate ligament transection (ACLT) model of induced OA and chondrocytes isolated from a patient with OA. Oral LMCP administration (100 or 200 mg/kg/day) for 12 weeks ameliorated cartilage damage and reduced the loss of proteoglycan compared to the findings in the ACLT control group, resulting in dose-dependent (p < 0.05) improvements of the OARSI score in hematoxylin & eosin (H&E) and Safranin O staining. In micro-computed tomography analysis, LMCP also significantly (p < 0.05) suppressed the deterioration of the microstructure in tibial subchondral bone during OA progression. The elevation of IL-1β and IL-6 concentrations in synovial fluid following OA induction was dose-dependently (p < 0.05) reduced by LMCP treatment. Furthermore, immunohistochemistry illustrated that LMCP significantly (p < 0.05) upregulated type II collagen and downregulated matrix metalloproteinase-13 in cartilage tissue. Consistent with the in vivo results, LMCP significantly (p < 0.05) increased the mRNA expression of COL2A1 and ACAN in chondrocytes isolated from a patient with OA regardless of the conditions for IL-1β induction. These findings suggest that LMCP has potential as a therapeutic treatment for OA that stimulates cartilage regeneration.

• KSBB Journal
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• v.23 no.5
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• pp.439-444
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• 2008

In this study, hair care effects of the hair cosmetics including low molecular weight silk peptide, hydrolysate which is produced from cocoon were investigated. After producing the hair cosmetics including silk peptide which has 300-500 molecular weight, we measured its hair care effects through the various tests; change of the hair weight, hair thickness, absorbance rate and hair moisture value and micro structure analysis. As a result, S.P.T. (Silk peptide Treatment) was effectively penetrated into the hair which has been damaged by chemical treatments, increased the hair weight, thickness and hair moisture value and also recovered the cuticle of the hair. Thus, the treatment of hair with silk peptide hydrolysate would be effective to recover the damaged hair into the normal conditions.

• Journal of the Korean Magnetic Resonance Society
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• v.24 no.4
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• pp.136-142
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• 2020

Apolipoprotein B-100 (apo B-100), the main protein component that makes up LDL (Low density lipoprotein), consists of 4,536 amino acids and serves to combine with the LDL receptor. The oxidized LDL peptides by malondialdehyde (MDA) or acetylation in vivo were act as immunoglobulin (Ig) antigens and peptide groups were classified into 7 peptide groups with subsequent 20 amino acids (P1-P302). The biomimetic peptide P99 (KGTYG LSCQR DPNTG RLNGE) out of B-group peptides carrying the highest value of IgM antigens were selected for structural studies that may provide antigen specificity. Circular Dichroism (CD) spectra were measured for peptide secondary structure in the range of 190-260 nm. Experimental results show that P99 has pseudo α-helice and random coil structure. Homonuclear (COSY, TOCSY, NOESY) 2D-NMR experiments were carried out for NMR signal assignments and structure determination for P99. On the basis of these completely assigned NMR spectra and proton distance information, distance geometry (DG) and molecular dynamic (MD) were carried out to determine the structures of P99. The proposed structure was selected by comparisons between experimental NOE spectra and back-calculated 2D NOE results from determined structure showing acceptable agreement. The total Root-Mean-Square-Deviation (RMSD) value of P99 obtained upon superposition of all atoms were in the set range. The solution state P99 has mixed structure of pseudo α-helix and β-turn(Gln[9] to Thr[13]). These NMR results are well consistent with secondary structure from experimental results of circular dichroism. Structural studies based on NMR may contribute to the prevent oxidation studies of atherosclerosis and observed conformational characteristics of apo B-100 in LDL using monoclonal antibodies.

• Journal of Integrative Natural Science
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• v.10 no.3
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• pp.154-161
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• 2017

An antimicrobial peptides-producing Bacillus strain CBS73 was isolated from fermented food (kimchi) that produces low-molecular-weight proteins with broad-spectrum antimicrobial activity. Our goal was to explore the therapeutic potential of antimicrobial substances produced by Bacillus species. Peptide CBS73 was purified from Bacillus subtilis subsp. subtilis with identity of 99.79%. It was found to be stable at pH 4.0-10.0 and temp $20-60^{\circ}C$. A protein band around 5.2 kDa was detected in tricine-SDS-PAGE and band was confirmed by MALDI-TOF test. Peptide CBS73 showed antimicrobial activity against MDR bacteria. The minimal inhibitory concentration (MIC) of peptide CBS73 for vancomycin-resistant S. aureus (VRSA), vancomycin resistant Enterococci (VRE) and Salmonella typhimurium ranged from $10-40{\mu}g/mL$. The antioxidant activity of peptide CBS73 was measured by DPPH scavenging, reducing power activity and total phenolic content. Cell viability and NO production result showed less cytotoxic effect upto $12{\mu}g/mL$. Peptide CBS73 could be a promising antimicrobial agent for clinical application.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.522-527
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• 2008

Low molecular peptides were isolated from Asterias amurensis via SDS-PAGE. The peptides were separated via consecutive gel filtration as five fractions (F1-F5) according to molecular weights, based on the results of MALDI-TOF MS analysis. The molecular weight of the most active peptide was estimated as 15,000 daltons. The peptide showed cytotoxicity on normal human fibroblast cells at levels as low as 20% when 1.0 mg/mL of the samples was added. The peptide also exhibited higher levels of nitric oxide production from macrophages than the lipopolysaccaharides. It was determined that prostaglendin $E_2$ production was significantly inhibited, up to 127.8% as compared to the control. The low molecular peptide inhibited hyaluronidase activity as 535.7 ${\mu}g/mL$ of $IC_{50}$. It can be concluded that the relatively low molecular weight peptide, fucoidan, from A. amurensis has excellent cosmetic and immunomodulatory activities, which can be considered as a possible resource of new cosmetic agents for skin immunomodulation.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1335-1340
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• 2006

It has been found that a number of diseases are associated with mutations in the mitochondrial DNA. Therapeutic gene delivery to mitochondria has been suggested as a clinical option for these diseases. In this study, we developed a gene carrier to mitochondria by the conjugation of mitochondrial leader peptide (LP) to polyethylenimine (PEI). Mitochondrial LP conjugated PEI (PEI-LP) was synthesized with low molecular weight PEI (2,000 Da, PEI2K). Gel retardation assay showed that PEI2K-LP formed complexes at a 1.0/1 weight ratio. In addition, PEI2K-LP protected DNA from the enzymatic degradation for at least 60 min, while naked DNA was completely degraded within 20 min. PEI2K-LP was compared with LP conjugated high molecular weight PEI (25,000 Da, PEI25K) in terms of toxicity and delivery efficiency. MTT assay showed that PEI2K-LP had much lower cytotoxicity than PEI25K-LP to 293 cells. In addition, cell-free DNA delivery assay showed that PEI2K-LP delivered more DNA to mitochondria at a 1.8/1 weight ratio than naked DNA or PEI. This result suggests that PEI2K-LP may be useful for the development of mitochondrial gene therapy system with lower cytotoxicity.