• Biotechnology and Bioprocess Engineering:BBE
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• 제6권6호
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• pp.410-418
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• 2001

The effects of several variables on the refolding of hen egg white lysozyme have been studied, Lysozyme was denatured in both urea, and guanidine hydrochloride(GuHCl), and batch refolded by dilution (100 to 1000 fold) into 0.1 M Tris-HCI, pH 8.2 mM EDTA 3 mM reduced glutathione and 0.3 mM oxidised glutathions. Refolding was found to be sensitive to temperature, with the highest refolding yield obtained at 50$\^{C}$. The apparent activation energy for lysozyme re-folding wasf ound to be 56kJ/mol, Refolding by dilution results in low concentrations of both de-naturant and reducing agent species. It was found that the residual concentrations obtained dur-ing dilution(100-fold dilution:[GuHCI]=0.06 mM, [DTT]=0.15 mM) were significant and could inhibit lysozyme refolding. This study has also shown that the initial protein concentration (1-10mg/mL) that is refolded is an important parameter. In the presence of residual GuHCl and DTT higher refolding yields were obtained when starting from higher initial lysozyme concentra-tions. This trend was reversed when residual denaturant components were removed from the re-folding buffer.

• Journal of Microbiology and Biotechnology
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• 제16권4호
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• pp.524-530
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• 2006

Two protease inhibitors of 67 and 18 kDa, respectively, were purified from the eggs of glass fish, Liparis tanakai, by affinity chromatography and electro-elution method. The high molecular weight (HMW) protein was purified with a specific inhibitory activity, yield, and purity of 18.46 U/mg, 0.07%, and 131.86 fold, respectively, and was further characterized: Optimal temperature and pH for inhibitory activity of the HMW glassfish egg protease inhibitor were $40^{\circ}C$ and pH 6, respectively, and it was stable between $5^{\circ}C\;and\;50^{\circ}C$ in the pH range of 5-6 with maximal stability at pH 6. It was shown to be a competitive inhibitor against papain with an inhibition constant $(K_i)$ of 97.02 nM. Moreover, the 67 kDa protein inhibited cathepsin, a cysteine protease, more effectively than did an egg-white protease inhibitor. The HMW glassfish egg protease inhibitor was classified as a member of the family III (kininogen).

• 한국축산식품학회지
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• 제38권6호
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• pp.1179-1188
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• 2018

This study aimed to investigate the combined effect of using natural calcium mixtures and various binding ingredients as replacers for synthetic phosphate in ground pork products. We performed seven treatments: control (0.3% phosphate blend), treatment 1 (0.5% natural calcium mixtures [NCM, which comprised 0.2% oyster shell calcium and 0.3% egg shell calcium powder] and 0.25% egg white powder), treatment 2 (0.5% NCM and 0.25% whey protein concentrate), treatment 3 (0.5% NCM and 0.25% concentrated soybean protein), treatment 4 (0.5% NCM and 0.25% isolated soybean protein), treatment 5 (0.5% NCM and 0.25% carrageenan), and treatment 6 (0.5% NCM and 0.25% collagen powder). All the treatment mixtures had higher pH and lower cooking loss than the control, which was treated with phosphate. We found that NCM and binding ingredients had no negative effects on the moisture content, lightness, and yellowness of the cooked ground pork products. Treatments 3 and 4 showed significantly lower CIE $a^*$ values than the control. Treatments 2 and 6 improved the textural properties of the products. In conclusion, the combination of NCM with whey protein concentrate or collagen powder could be suitable for producing phosphate-free meat products.

• 멤브레인
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• 제26권4호
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• pp.266-272
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• 2016

전량여과(dead-end filtration)를 사용하여 계란 난백용액으로부터 라이소자임 효소의 분리정제에 대한 연구를 수행하였다. 전량여과 시 사용된 한외여과 막의 분획분자량과 난백용액의 pH 변화에 따른 라이소자임의 난백에 존재하는 다른 종류의 단백질인 오발부민과 콘알부민에 대한 막을 통한 투과선택도(permselectivity)를 측정하여 투과선택도가 가장 큰 값을 나타내는 전량여과의 최적 운전조건을 결정하였다. 이 결과 난백용액으로 라이소자임을 효과적으로 투과 분리시키기 위한 최적 운전조건은 한외여과 막의 분획분자량 30 kDa, 난백용액의 pH 11이었다. 최적 운전조건에서 난백 내 총 단백질에 대한 라이소자임의 투과선택도가 약 83의 가장 큰 값을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권11호
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• pp.1476-1481
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• 2010

This study was conducted to evaluate the effects of dietary supplementation with chito-oligosccharide (COS) on egg production, nutrient digestibility, egg quality and blood profiles in laying hens. A total of 240 Hy-line Brown laying hens were randomly allocated into one of the following 5 dietary treatments: i) CON, basal diet; ii) ANT, basal diet+44 mg/kg avilamycin; iii) COS0.2, basal diet+200 mg/kg COS; iv) COS0.4, basal diet+400 mg/kg COS; v) ANTCOS, basal diet+200 mg/kg COS+22 mg/kg avilamycin. The experiment lasted for 6 wk. No change in egg weight (p>0.05) was observed during the trial period. Egg production in ANTCOS treatment was improved (p<0.05) when compared to CON during weeks 4-6. The birds in the COS0.2, COS0.4 and ANTCOS groups had higher (p<0.05) Haugh unit than those fed CON and ANT diets at the end of the $6^{th}$ wk. The apparent digestibility of nitrogen in CON group was lower (p<0.05) than in other treatments. The white blood cell (WBC) concentration of birds in the COS0.4 and ANTCOS group was higher (p<0.05) than that of birds in other groups at the end of the $6^{th}$ wk. In addition, the differences of WBC counts between the beginning and end of the experiment in COS0.4 and ANTCOS groups were higher (p<0.05) than in CON and ANT groups. At the end of the experiment, the birds fed ANTCOS diet showed higher (p<0.05) total blood protein concentration than those fed CON or ANT diets. In conclusion, dietary supplementation of COS appeared to increase egg production and quality by increasing nutrient digestibility. Additionally, COS improved WBC and total protein concentration.

• 대한의생명과학회지
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• 제19권3호
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• pp.270-274
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• 2013

Egg allergy has been raised as the most prevalent food hypersensitivity in children. Ovalbumin (OVA), which is one of the major egg allergens, is the major protein in egg white. Isoliquiritigenin (ILG) is an active component present in licorice and has been used to treat many chronic diseases for many years. In this study, we present biochemical evidence that ILG inhibits OVA-induced nuclear factor-${\kappa}B$ (NF-${\kappa}B$) activation. ILG also inhibits OVA-induced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression. These data suggest that ILG has anti-allergy effects.

• 한국결정학회지
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• 제5권1호
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• pp.33-38
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• 1994

Hen egg white Iysozyme과 equine serum albumin을 모델 단백질로 하여 'heterogeneous' vapor diffusion실험을 수행하였다. 즉, droplet과 reseroir용액에 각각 다른 침전제를 사용하여 vapor diffusion에 의하여 평형에 이르도록 하였다. 실험 결과는 NSI 혹은 ammonium sulfate 대신 polyethylene glycol이 reservoir 용액에 포함되므로써 droplet과 reservoir 용액 사이의 평형 속도가 감소되는 것을 보여 주었다. Heterogeneous vapor diffusion 법을 통하여 reservoir용액에 포함된 이온성 염과 비이온성 침전제의 양을 적절히 조절하여 평형속도를 조절할 수 있음을 보였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.493-496
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• 2002

용균작용을 하는 lysozyme을 난백으로부터 분리하기 위해 이온교환크로마토그래피를 사용하였다. 용출시에 gradient를 걸어준 결과 젤과 약하게 결합된 단백질과 강하게 결합된 단백질이 분리되어 나옴을 SDS-PAGE와 Lowry methode를 통하여 알 수 있었다.

• 한국식품영양과학회지
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• 제27권2호
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• pp.291-295
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• 1998

The ovalbumins obtained from hen's and duck's egg white were irradiated with up to 100 kGy at room temperature. The purified proteins were evaluated for their in vitro digestibility by incubating successively with pepsin and pancreatin conjugate. Amino acid compositions and SDS-PAGE pattern in these proteins were also analyzed. The obtained results indicated that gamma irradiation within the tested dose range(up to 100kGy) produced no statistically significant changes in the in vitro digestibility an amino acid compositions. Analysis of gamma-irradiated ovalbumins by SDS-PAGE revealed radiolysis of ovalbumin into proteins or peptides of low molecular weights.

• Preventive Nutrition and Food Science
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• 제5권2호
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• pp.65-69
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• 2000

Hen egg-white lysozyme was conjugated with 7~9 mers xyloglucan hydrolysates(MW-1,400) at 6$0^{\circ}C$ and 79% relative humidity for 3 days. SDS-PAGE showed that the conjugation between lysozyme and the oligosaccharide began from 1-day incubation, and three molecules of carbohydrate chains were attached to a protein molecule after 30day incubation. The enzymatic activity of lysozyme was totally conserved in the neoglycoprotein, when measured by using glycol chitin as substrate. Besides, the emulsifying properties of lysozyme were vastly improved by the conjugation with the oligosaccharide, in which emulsifying activity of the neoglycoprotein was five times higher than that of native one.