• 한국식품과학회지
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• 제24권4호
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• pp.393-395
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• 1992

HPLC에 의한 원유의 ${\alpha}-lactalbumin$ 농도는 열처리하지 않은 경우, $63^{\circ}C$에서 30분 살균한 경우, $72^{\circ}C$에서 15초 살균한 경우, $100^{\circ}C$에서 10분간 가열한 경우 각각 1.20, 1.17, 1.13, 0.00 mg/ml이었다. 한편, 시판우유 중의 ${\alpha}-lactalbumin$ 농도 범위는 살균유, UHT 처리유, 멸균유에 있어서 각각 $1.00{\sim}1.02$, $0.23{\sim}0.68$, $0.77{\sim}0.89mg/ml$이었다. UHT 멸균유(롱우유)의 ${\alpha}-lactalbumin$ 함량이 UHT 살균유보다 더 낮을 것으로 예상되었으나 오히려 더 높게 나타났는데, 이는 유가공 회사에서 수행한 열처리 조건의 차이에서 기인하는 것으로 추정된다. 이 차이는 우유공장에서 다른 열처리 시스템, 즉 간접식 UHT 살균처리법이 직접식 UHT 가공처리법보다 열처리 강도가 더 크기 때문에 야기될 수 있을 것이다. 본 실험결과 HPLC를 이용하여 우유중의 ${\alpha}-lactalbumin$을 열처리의 지표물질로써 신속, 정확하게 정량할 수 있을 것으로 사료되었다.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2000년도 국제심포지움
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• pp.1-2
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• 2000

High production of milk and its components are necessary to allow maximal growth of developing piglets. In this study, transgenic pigs were produced containing the $\alpha$-lactalbumin gene, whose product is a potential limiting component in the production of milk. Two lines of transgenic pigs were produced to analyze the effects that overproduction of the milk protein $\alpha$-lactalbumin may have on milk production and piglet growth. Transgenic pigs were produced through microinjection of the bovine $\alpha$-lactalbumin gene. The gene construct contained 2.0 kb of 5 flanking region, the 2.0 kb coding region and 329 bp of 3 flanking region. Sows hemizygous for the transgene produced as much as 0.9 g of bovine $\alpha$-lactalbumin per liter of pig milk. The production of the bovine protein caused approximately a 50 % increase in the total $\alpha$-lactalbumin concentration in pig milk throughout lactation. The concentration of bovine $\alpha$-lactalbumin was highest on day 0 and 5 of lactation and decreased as lactation progressed. The ratio of bovine to porcine $\alpha$-lactalbumin changed during the sow's lactation. This ratio was 4.3 to 1 on day 0 of lactation, but by day 20 of lactation the ratio was 0.43 to 1. This suggested that the bovine transgene and the endogenous porcine gene were under slightly different control mechanisms. The higher level of total $\alpha$-lactalbumin present on day 0 of lactation was correlated with higher lactose percentage on day 0 in transgenic sows (3.8 %) as compared to controls (2.6 %) (P < 0.01). Although there was also a trend for higher lactose percentage in transgenic sows on day 5 and 10 of lactation, no significant differences were observed. These data suggest that $\alpha$-lactalbumin is limiting early in lactation of swine. Furthermore, higher concentrations of $\alpha$-lactalbumin early in lactation may boost milk output.

• 한국가축번식학회지
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• 제24권4호
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• pp.321-333
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• 2000

High production of milk and its components are necessary to allow maximal growth of developing piglets. In this study, transgenic pigs were produced containing the $\alpha$ -lactalbumin gene, whose product is a potential limiting component in the production of milk. Two lines of transgenic pigs were produced to analyze the effects that overproduction of the milk protein $\alpha$ -lactalbumin may have on milk production and piglet growth. Transgenic pigs were produced through microinjection of the bovine $\alpha$ -lactalbumin gene. The gene construct contained 2.0 kb of 5'flanking region, the 2.0 kb coding region and 329 bp of 3'flanking region. Sows hemizygous for the trans gene produced as much as 0.9 g of bovine $\alpha$-lactalbumin per liter of pig milk. The production of the bovine protein caused approximately a 50% increase in the total $\alpha$ -lactalbumin concentration in pig milk throughout lactation. The concentration of bovine $\alpha$ -lactalbumin was highest on day 0 and 5 of lactation and decreased as lactation progressed. The ratio of bovine to porcine $\alpha$ -lactalbumin changed during the sow's lactation. This ratio was 4.3 to 1 on day 0 of lactation, but by day 20 of lactation the ratio was 0.43 to 1. This suggested that the bovine transgene and the endogenous porcine gene were under slightly different control mechanisms. The higher level of total $\alpha$-lactalbumin present on day 0 of lactation was correlated with higher lactose percentage on day 0 in transgenic sows (3.8%) as compared to controls (2.6%) (P＜0.01). Although there was also a trend for higher lactose percentage in transgenic sows on day 5 and 10 of lactation, no significant differences were observed. These data suggest that $\alpha$ -lactalbumin is limiting early in lactation of swine. Furthermore, higher concentrations of $\alpha$ -lactalbumin early in lactation may boost milk output.

• KSBB Journal
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• 제16권6호
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• pp.533-537
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• 2001

유청 단백질 중에서 $\alpha$-lactalbumin, $\beta$-lactoglobulin를 고성능 막 크로마코그래피를 이용하여 분리하는 것이다. 분리 메카니즘은 음이온 교환작용이며 고정상은 CIM DEAE, QA, So$_3$ disk (16$\times$3 mm)을 사용하였다. 이동상은 buffer A (20 mM Tris-HCI, pH 7.3)와 buffer B (buffer A + 1 M NaCl)를 사용하였으며 $\alpha$-lactalbumin, $\beta$-lactoglobulin를 분리하기 위해서 구배용매 조성법을 사용하였다. 각 이동상의 조성에 따른 최적의 이동상 조성(Buffer A/Buffer B=100/0 - 30/70 vol%, gradient time 1 min, 30/70 - 10/90 vol%, gradient time 2 min)을 실험적으로 얻었고 4 ml/min의 이동상 유속에서 3분내에 $\alpha$-lactalbumin, $\beta$-lactoglobulin를 분리 할 수 있었다. 유청 단백질 중에 $\alpha$-lactalbumin, $\beta$-lactoglobulin을 HPMC을 적용하여 분리하였고, 유청 단백질의 기능적 성질, 분리 방법에 대해 알아보았다.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.179-182
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• 2004

This study reports the extraction behavior of $\alpha$-lactalbumin using bis(2-ethylhexyl) sulfosuccinate sodium (AOT) reverse micelles. Forward extraction of $\alpha$-lactalbumin in the reverse micellar organic phase from aqueous feed solutions was strongly dependent on the AOT concentration and the complete forward extraction of 0.03 mM $\alpha$-lactalbumin was successfully achieved at an AOT concentration of ca. 100 mM. A similar dependency of the forward extraction on the AOT concentration was obtained in isooctane, n-hexane, and n-octane systems. In the backward extraction from the micellar organic phase, the recovery of the protein as high as ca. 90% was obtained with pH control and/or salt addition.

• Bulletin of the Korean Chemical Society
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• 제22권2호
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• pp.145-148
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• 2001

The interaction between tetradecyl trimethyl ammonium bromide (TTAB) with bovine ${\alpha}-lactalbumin$ has been investigated at pH = 9 and at $37^{\circ}C$ by isothermal titration calorimetry, equilibrium dialysis and UV-Vis spectrophotometry methods. The binding data from unusual Scatchard plot have been analyzed in terms of the Hill equation for three sets of binding sites. The calorimetric data show that TTAB interacts endothermically with ${\alpha}-lactalbumin$ and causes protein unfolding below 2 mM concentration of TTAB, which is confirmed by spectrophotometric data. The unfolding of the protein would be mainly due to occupation of the second set of binding sites.

• Preventive Nutrition and Food Science
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• 제7권1호
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• pp.48-51
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• 2002

In order to study the reaction behavior of bovine holo- and apo-$\alpha$-lactalbumin ($\alpha$-La) during heat treatment at 65~10$0^{\circ}C$, the samples were analysed by first (ID)-and second-dimensional (2D) native-polyacrylamide gel electrophoresis (Native-PAGE) and sodium dodecylsulfate (SDS)-PAGE. When bolo-$\alpha$-La or apo- $\alpha$ -La were heated, they formed non-native, monomers, dimers and trimers. The apo-$\alpha$-La was more heat-sensitive than holo-$\alpha$-La. The monomers seemed to have the same composition as the native $\alpha$-La, but many of the disulfide bonds could be non-native.

• 한국축산식품학회지
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• 제22권1호
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• pp.72-76
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• 2002

상업적으로 생산 판매되고 있는 여러 가지 유청 단백질을 이용하여 각종 암세포에 대한 세포독성을 조사한 결과, IgG, BSA, $\beta$-LG는 세포독성이 거의 없었으나, $\alpha$-LA가 강한 세포독성을 갖고 있음이 확인되었다. MKN45, HeLa, WiDr, 그리고 A498의 경우, $\alpha$-LA(1mg/ml)에 의해 세포성장이 95% 이상 억제되는 것으로 나타났다. HPLC를 이용하여 $\alpha$-LA에 혼입되어 있는 미량성분을 제거한 후, 세포독성을 조사한 결과, $\alpha$-LA이 나타내었던 세포독성이 대부분 없어지는 것으로 나타났다. 또한 $\alpha$-LA을 trypsin으로 부분 가수분해한 후, 각종 암세포에 대한 성장 억제효과를 검토한 결과, 암세포에 대한 독성을 상실하는 것으로 나타났으며, $\alpha$-LA를 EDTA로 처리할 경우, $\alpha$-LA의 세포독성이 대부분 상실되는 것으로 나타났다.

• 한국축산식품학회지
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• 제18권1호
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• pp.9-18
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• 1998

This study was performed to obtain a large quantity of $\alpha$-lactalbumin ($\alpha$-LA) from milk by an improved separation and purification method. Functional properties-solubility viscosity, emulsifying activity, foamability surface hydrophobicity and gelation-of the purified $\alpha$-LA were investigated, $\alpha$-LA was purified in a large quantity by DEAE-Sephacel chromatography using 0.15M NaCl in 20mM Tris-HCl buffer(pH 7.2), as an eluent. The yield and purity of the purified $\alpha$-LA were 23.6%, 92.5%, respect-ively. The solubility viscosity and emulsifying activity of the purified $\alpha$-LA were 92.2$\pm$2% 3.46$\pm$0.19 cP and 345$\pm$5.0m^2$-/g respecively. The foamability of $\alpha$ -LA was 762 after 5min whipping which was lower than that of WPC and showed decreasing tendency with whipping time. The relative surface hydrophobicity of the $\alpha$-LA was formed when a 10% $\alpha$-LA solution containing 100mM NaCl and 20 mM $CaCl_2$ was heated at 92$^{\circ}C$for 40min. The $\alpha$-LA gel showed 31.5 as hardness and showed low springiness and cohesiveness.

• 농업과학연구
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• 제39권4호
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• pp.561-568
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• 2012

The aim of this study was to introduce a simple method for isolation of ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin and bovine serum albumin from cow's milk, and peptides produced by enzymatic hydrolysis of ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin and bovine serum albumin with alcalase. Whey protein were precipitated from whey by ammonium sulfate and, ${\alpha}$-lactalbumin and ${\beta}$-lactoglobulin were isolated using Hi Prep 26/60 Sephacryl S-100 column gel filtration chromatography. Bovine serum albumin and ${\beta}$-lactoglobulin were isolated by Mono-Q 5/50 GL column anion exchange chromatography of the 50% Ammonium Sulfate-supernatant. Isolated whey proteins were hydrolyzed by proteolytic alcalase. Tricine SDS-PAGE and reverse-phase HPLC analyses revealed that almost hydrolyzed all the ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin and bovine serum albumin with alcalase. Molecular weight of various peptides derived from alcalase hydrolysate were small molecular weight than 3.5 kDa.