• BMB Reports
• /
• 제29권3호
• /
• pp.236-240
• /
• 1996

A 23-kDa molecular mass of antioxidant protein was purified from human liver. This protein exhibited the preventive effect against the inactivation of glutamine synthetase by a metal-catalyzed oxidation system. This antioxidant activity was supported by a thiol-reducing equivalent such as dithiothreitol in a similar manner to that of the 25-kDa thiol-specific antioxidant protein (TSA) from human red blood cells (HR). However, a thioredoxin-linked peroxidase activity of thiol-specific antioxidant protein of human liver (HLTSA) (0.91 ${\mu}mol/min/nmol$ of HLTSA) was much lower than that of thiol-specific antioxidant protein of human red blood cells (HRTSA) (16.4 ${\mu}mol/min/nmol$ of HRTSA). This HLTSA is also immnologically distinct from HRTSA Amino acid sequences of the three tryptic peptides (P1, P2, P3) of HLTSA were found to be completely homologous to segments of the known Mer5-like protein, which belongs to the known TSA family.

• 한국축산식품학회지
• /
• 제37권5호
• /
• pp.764-772
• /
• 2017

Fertilized hen eggs are rich in a variety of bioactive ingredients. In this study, we aimed to obtain an antioxidant protein from fertilized eggs and the radical scavenging abilities on 1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (${\bullet}OH$), superoxide anion ($O^{2-}{\bullet}$) were used to evaluate the antioxidant activity of the purified protein. During 20 d of incubation, the radical scavenging ability of protein extracted from fertilized eggs exhibited significantly differences and the protein on day 16 showed higher antioxidant capacity. Based on this, the antioxidant protein of the samples on day 16 were isolated for the follow-up study. With a molecular weight 43.22 kDa, the antioxidant protein was purified by Diethylaminoethyl cellulose -52 (DEAE-52) column and Sephadex G-100. The LC-MS analysis showed that the purified protein molecular weight was 43.22 kDa, named D2-S. The sequence of amino acids was highly similar to ovalbumin and the coverage reached to 84%. The purified protein showed a radical scavenging rate of $52.34{\pm}3.27%$ on DPPH and $63.49{\pm}0.25%$ on ${\bullet}OH$, respectively. Furthermore, the C-terminal amino acid sequence was NAVLFFGRCVSP, which was consistent with the sequence of ovabumin. These results here indicated that purified protein may be a potential resource as a natural antioxidant.

• 한국조리학회지
• /
• 제24권2호
• /
• pp.103-111
• /
• 2018

The objectives of the present study were to examine the antioxidant activity of autofocusing fractions from egg white protein hydrolysates and obtain higher antioxidant peptide fraction, which could be applied to the food model system. Alkaline protease hydrolysate of egg white protein exerted higher antioxidant activities than other protein hydrolysates and were fractionated on the basis of the amphoteric nature of sample peptides by preparative isoelectric focusing without toxic solvents and reagents, which is termed autofocusing. Neutral and basic fractions showed higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than the acidic fractions. The acidic and neutral fractions showed higher hydroxyl (OH) radical scavenging activity and oxygen radical absorbance capacity (ORAC) values than the basic fractions. The acidic fractions showed higher metal chelating activity than basic fractions. Antioxidant activities of some autofocusing fractions except for ORAC showed higher compared to the crude hydrolysate. These results suggest that peptides fractions from egg white protein are effective antioxidant, and that autofocusing could be useful to increase antioxidant activity for application to food system.

• 자연과학논문집
• /
• 제4권
• /
• pp.1-10
• /
• 1991

발현 Vector인 pKK223-3를 이용하여 효모 Thiol-Specific Antioxidant단백질 유전자를 대장균에 도입시켜 이 단백질을 발현시켰다. 이 단백질은 대장균 단백질의 약 1% 정도로 발현되었으며, 물리 및 화학적 특성은 효모의 것과 동일한 특성을 보였다.

• Journal of Nutrition and Health
• /
• 제33권6호
• /
• pp.613-618
• /
• 2000

This study was to investigate the effect of dietary protein and fiber on the antioxidant enzyme activities of brain in acute or chronic ethanol-treated rats. Male Sprague-Dawley rats were fed on diets containing two levels of protein(7%, 20%) with two levels of fiber (5%, 10%) Rats were administered 40%(v/v) ethanol(5g/kg body weight)orally 90min before decaptiation in acute ethanol-treated groups and 25%(v/v) ethanol(5g/kg body weight) once a day for 5 weeks in chronic ethanol treated-groups. The rats were sacrificed after 5 weeks of feeding periods. Superoxide dismutase and gluthathione S-transferase activities were lower in chronic ethanol-treated groups than acute ethanol-treated groups whereas catalase and glutathuone peroxidase activities were significantly increased by chronic ethanol treatment. Low protein supplement accelerated to change of their activities however dietary fiber levels did not affect antioxidant enzyme activities. Chronic ethanol treatment and/or low protein supplement results in increasing the brain lipid peroxide content but in lowering glutathione level. (Korean J Nutrition 33(6) ; 613~618, 2000)

• 한국축산식품학회지
• /
• 제36권6호
• /
• pp.791-798
• /
• 2016

Free radicals may attack cells or tissue, leading to chronic diseases, and antioxidant consumption is potentially useful for removing free radicals. Egg proteins may be used as potential sources of antioxidant considering their ability of scavenging free radicals to apply for food or cosmetics industry. In this study, we obtained a natural antioxidant protein from fertilized eggs, which was a dietary supplement in some Asian countries. Meanwhile, antioxidant activities of these proteins were evaluated using different oxidation systems. With increasing incubation time, the antioxidant activity of these proteins increased during 15 d of incubation. The samples on day 15 were performed for isolation of antioxidant protein. The protein, named P4-1 (MW, 45 kDa), was isolated and purified by consecutive chromatographic methods. P4-1 contained 17 amino acids, which was determined by liquid chromatography-mass spectrometry and Amino Acid Analyzer. Moreover, the amino acid sequence was highly similar to that of ovalbumin. Differential scanning calorimetry showed that the denaturation temperature of P4-1 was $57.16^{\circ}C$. Furthermore, P4-1 suggested high oxygen radical-absorbance activity in ${\cdot}OH$ assays, and its antioxidant activity was stable at $30-50^{\circ}C$ in acidic and neutral pH. Thus, these results revealed that P4-1 may be a potential resource as a natural antioxidant.

• International Journal of Oral Biology
• /
• 제30권3호
• /
• pp.77-84
• /
• 2005

EGCG[(-)-epigallocatechin gallate], is a major component of green tea has been considered as a major antioxidant constituent. It has been considered as potential chemopreventive and chemotherapeutic agents. However, very little is known about the cellular actions by which EGCG mediates its therapeutic effects. Various aspects of antioxidant activity of EGCG were evaluated in this study. EGCG itself did not show significant cytotoxicity. Significant 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was observed in all ranges of concentration ($0.8-100{\mu}g/ml$) used in this study. Protective effect of EGCG against hydrogen peroxide induced cell death was observed. Relatively high lipid peroxidation inhibitory activity were detected ($IC_{50}$ was about $20{\mu}g/ml$). EGCG also dose-dependently enhanced the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in V79-4 cells. In concentrations of $100{\mu}g/ml$ of EGCG, activities of SOD, CAT and GPX were measured as 36.9 U/mg of protein, 22.9 U/mg of protein and 17.8 U/mg of protein, respectively. When these values were compared with those of the control groups (24.9 U/mg of protein, 14.9 U/mg of protein and 11.7 U/mg of protein), the relative increases were calculated as 48, 54 and 52%, respectively. Taken together, our findings suggest that EGCG can act as an antioxidant by scavenging radicals and enhancing antioxidant enzyme activities.

• 한국식품저장유통학회지
• /
• 제30권3호
• /
• pp.434-445
• /
• 2023

Hemp (Cannabis sativa L.) seeds have recently been attracting attention as a new high-value-added food material owing to their excellent nutritional properties, and research on the development of functional food materials using hemp seeds is actively progressing. This study aimed to evaluate the antioxidant properties of hemp seed protein hydrolysates. Protein hydrolysates were prepared from defatted hemp seed powder (HS) by enzymatic hydrolysis using five different proteases (alcalase, bromelain, flavourzyme, neutrase, and papain). 2,4,6-trinitrobenzene sulfonic acid (TNBS) assay and SDS-PAGE analysis revealed that HS showed a high degree of hydrolysis after treatment with each enzyme except papain. The total polyphenol content of the protein hydrolysates (<3 kDa) and the RC50 values obtained from two different antioxidant tests showed that alcalase hydrolysate (HSA) had a relatively high level of antioxidant capacity. In addition, treatment with HSA (25-100 ㎍/mL) significantly inhibited linoleic acid peroxidation. These results suggest that hemp seed protein hydrolysates are potential sources of natural antioxidants. Future studies will focus on the identification of active peptides from HSA.

• 생명과학회지
• /
• 제20권10호
• /
• pp.1483-1489
• /
• 2010

실험동물은 생후 5주령의 Sprague Dawely계 수컷 흰쥐로 운동+단백질식이군(11마리), 운동군(11마리), 단백질식이군(11마리), 대조군(11마리)으로 총 44마리로 구분하였다. 운동은 총 4주간 트레드밀운동으로 주 5회, 1일 20분, 점진적으로 운동강도를 높여 실시하였고, 식이는 단백질 40%를 섭취시켜 다음과 같은 결론을 얻었다. 면역글로불린에서 IgG은 단백질식이군이 운동군과 대조군보다 높았다. 항산화효소에서 SOD는 운동+단백질식이군과 단백질식이군이 대조군보다 유의하게 높았고, GPx는 운동+단백질식이군, 운동군, 단백질식이군이 대조군보다 유의하게 높았으며, CAT는 운동+단백질식이군이 단백질식이군과 대조군보다 유의하게 높았다. 이상의 결과를 통해 트레드밀운동과 단백질식이가 면역글로불린 및 항산화 효소에 긍정적인 영향을 미친 것으로 생각되며, 향후 운동강도와 단백질식이와 관련하여 지속적인 연구가 필요하다.

• 한국식품저장유통학회지
• /
• 제24권4호
• /
• pp.542-549
• /
• 2017

In this study, a peptide exhibiting antioxidant activity was isolated from sandfish (Arctoscopus japonicus) roe hydrolysate (SRH) in order to evaluate their practical uses as materials for manufacturing functional foods. The A. japonicus roe protein was hydrolyzed using Collupulin MG, and isolation of antioxidant peptide was performed using ultrafiltration (UF), prep-HPLC, and RP-HPLC. The SRH with a molecular weight below 3 kDa constituted about 38% of the whole hydrolysate, and the fraction with a molecular weight below 3 kDa showed significantly greater antioxidant activity compared to the original SRH and other fractions. The isolation fold of the antioxidant peptide isolated from SRH throughout the four-step procedure was 7.11-fold, and protein yield was 14.8%. The DPPH radical scavenging activity of isolated antioxidant peptide was above 90% at a concentration of 1.0 mg/mL, which was similar to that of the Trolox at a concentration of 0.1 mg/mL. These results suggested that the antioxidant peptide derived from A. japonicus roe could be a useful additive for producing functional foods and protein supplements. However, it is necessary to perform further study the structural characteristics of this antioxidant peptide isolated from A. japonicus roe.