• 한국식품과학회지
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• 제21권4호
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• pp.492-497
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• 1989

천연식품성분에 의한 항산화기작을 해명하기 위하여 어육단백질, 탈지대두박, egg albumin 및 casein등의 단백질 가수분해물을 사용하여 linoleic acid 와의 모델계 반응을 통하여 이들의 항산화능과 ${\alpha}-tocopherol$과의 상승작용 및 금속이온 봉쇄능 등에 대하여 연구 검토하였는데 그 결과 각 단백질 가수분해물은 항산화능이 매우 큰 것으로 나타났으며. 특히 egg albumin가수분해물의 항산화능이 매우 강한 것으로 나타났다. 또한 천연항산화제인 ${\alpha}-tocopherol$과의 상승작용도 우수한 것으로 나타났는데 단백질 가수분해물간의 차이는 거의 없는 것으로 나타났다. 금속이온 봉쇄능 또한 높게 나타났으며 단백질 가수분해물의 금속이온 봉쇄능은 금속이온의 종류에 따라 다소 차이가 있는 것으로 나타났다.

• 생명과학회지
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• 제6권2호
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• pp.94-103
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• 1996

To understand effect of inoculum size, cell density, sucrose concentration and concentrations of MS basal on suspension culture and protoplast isolation of wild viola(Viola patrinii DC.) callus from petiole segments this experiment was conducted. In the lot of 30 mesh inoculum size, two observations were; One was that a considerable increase in the fresh and dry weight of callus was determined. Another was that the callus mass was relatively compact compared with others. A recommendable cell density was 0.4g for 20ml culture medium and the higher sucrose concentration, the higher fresh and dry weight were obtained. The dilution of MS basal salt was differently affected on fresh and dry weight; the highest fresh weight was found in 1x MS salt, while the higest dry weight was in 1/3x dilution.The addition of casein hydrolysate(3g/L) was more effective to increase of both fresh and dry weight. THe contents of protein was great in the inoculum lots with larger inoculum sizeand higher concentration of MS basal salts contenting 3g/L of casein hydrolysate and higher sucrose compared with others. The greatest protoplasts were isolated from the lot of 10 mesh size treated with 1%pectinase SE-150 and 2% cellulase YC. In general, for optimal protoplast isolation the followingconditions were recommended; 1) Use of smaller cell size cultured for 2-5 weeks, and 2) more than 5 hours incubation using the combined mixture of the enzymes with proper concentrations.

• 한국식품영양과학회지
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• 제22권2호
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• pp.226-233
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• 1993

효소에 의한 가수분해로 식품단백질로부터 생리활성 peptide의 생성을 밝히기 위한 연구의 일환으로 효소에 의한 단백질 가수분해물의 ACE 저해작용을 검토한 결과는 다음과 같다. 1. 가수분해에 따른 ACE 저해능은 가수분해 8시간까지는 급격히 증가하다가 그 후로는 완만하게 증가하였으며, 특히 복합효소, bromelain 및 pepsin등에 의해 우수하게 나타났다. 그러나 trypsin 및 $\alpha$-chymotrypsin에 의한 egg albumin 및 casein 가수분해시에는 가수분해 8시간 이후에는 오히려 감소하는 경향을 나타내었다. 2. 단백질 가수분해물의 ACE 저해능은 첨가량의 증가와 함께 우수한 것으로 나타났으며, 가열에 대하여 비교적 안정한 것으로 나타났다. 3. 단백질 가수분해물의 아미노산 조성은 거의 유사한 것으로 나타났으며, 특히 glutamic acid의 함량이 월등히 많은 것으로 나타났다. 그러나 egg albumin 가수분해물의 경우는 glutamic acid의 함량이 적은 반면 alanine 및 cysteine의 함량이 다소 많은 것으로 나타났다 4. Gel 여과에 의한 단백질 가수분해물의 획분별 ACE 저해작용은 서로 비슷한 획 분에서 나타났으며 이 때의 분자량은 1,400부근으로 나타났다. 5. Gel 여과에 의한 ACE 저해작용 획분의 아미노산 조성은 서로 다른 것으로 나타났다.

• Nutrition Research and Practice
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• 제18권1호
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• pp.46-61
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• 2024

BACKGROUND/OBJECTIVES: An increasing life expectancy in society has burdened healthcare systems substantially because of the rising prevalence of age-related metabolic diseases. This study compared the effects of animal protein hydrolysate (APH) and casein on metabolic diseases using aged mice. MATERIALS/METHODS: Eight-week-old and 50-week-old C57BL/6J mice were used as the non-aged (YC group) and aged controls (NC group), respectively. The aged mice were divided randomly into 3 groups (NC, low-APH [LP], and high-APH [HP] and fed each experimental diet for 12 weeks. In the LP and HP groups, casein in the AIN-93G diet was substituted with 16 kcal% and 24 kcal% APH, respectively. The mice were sacrificed when they were 63-week-old, and plasma and hepatic lipid, white adipose tissue weight, hepatic glucose, lipid, and antioxidant enzyme activities, immunohistochemistry staining, and mRNA expression related to the glucose metabolism on liver and muscle were analyzed. RESULTS: Supplementation of APH in aging mice resulted in a significant decrease in visceral fat (epididymal, perirenal, retroperitoneal, and mesenteric fat) compared to the negative control (NC) group. The intraperitoneal glucose tolerance test and area under the curve analysis revealed insulin resistance in the NC group, which was alleviated by APH supplementation. APH supplementation reduced hepatic gluconeogenesis and increased glucose utilization in the liver and muscle. Furthermore, APH supplementation improved hepatic steatosis by reducing the hepatic fatty acid and phosphatidate phosphatase activity while increasing the hepatic carnitine palmitoyltransferase activity. Furthermore, in the APH supplementation groups, the red blood cell (RBC) thiobarbituric acid reactive substances and hepatic H₂O₂ levels decreased, and the RBC glutathione, hepatic catalase, and glutathione peroxidase activities increased. CONCLUSIONS: APH supplementation reduced visceral fat accumulation and alleviated obesity-related metabolic diseases, including insulin resistance and hepatic steatosis, in aged mice. Therefore, high-quality animal protein APH that reduces the molecular weight and enhances the protein digestibility-corrected amino acid score has potential as a dietary supplement for healthy aging.

• 한국응용곤충학회지
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• 제38권1호
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• pp.35-39
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• 1999

진딧물류의 천적인 칠성풀잠자리붙이(Chrysopa pallens Ramber)를 계란의 난황, 효모가 수분해물, 맥주효모 또는 Vanderzant의 비타민 혼합물, 설탕과 벌꿀 또는 설탕, 카세인가수분해물, 콜레스테롤로 구성된 인공사료를 이용하여 사육하였다. 인공사료의 조성에 따라 1령유충부터 사육한 결과 20~70%가 정상적인 성충으로 자랐으며, 사육성적이 가장 뛰어났던 인공사료를 성충에 먹였을 때 230개의 수정란을 36일간에 걸쳐 산란하였다. 복숭아진딧물의 비지질성분이 지질성분보다 칠성풀잠자리붙이의 발육에 영양원면에서 더 중요한 것으로 나타났다.

• 한국축산식품학회지
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• 제29권5호
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• pp.633-639
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• 2009

본 연구는 유단백질에 단백질 분해효소를 처리하여 가수분해 후 저분자 peptide를 ABTS법을 이용하여 항산화 활성을 측정하여 유단백질 유래 저분자 peptide의 항산화력을 측정하고자 하였다. Chymotrypsin 처리한 유청단백질의 가수분해도가 가장 높았으며, 유청단백질의 락트알부민 및 락토글로브린이 분해되어 분자량 20 kDa 이하의 저분자 단백질이 생성된 것을 전기영동을 통하여 확인하였다. 유단백질의 농도에 따른 항산화 활성을 측정한 결과, 카제인의 항산화 활성이 유청단백질보다 높게 나타났다. 유단백질을 효소에 의하여 가수분해 시 항산화 활성이 증가하였으며, 카제인 가수분해물이 유청단백질 가수분해물과 비교하여 항산화 활성이 더 높았으나, 가수분해도와 항산화 활성도의 관계는 일치하지 않았다. Trypsin에 의한 카제인 가수분해 물의 항산화 활성이 80.7%로 가장 높았다. 본 연구에서는 chymotrypsin과 trypsin에 의한 분자량 3 kDa의 카제인 분획물의 항산화 활성이 가장 우수 하였으며, 유청단백질을 trypsin으로 분해하였을 때 항산화 활성이 증가하였다.

• 한국식품과학회지
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• 제20권5호
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• pp.659-665
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• 1988

식품에서의 쓴 맛 펩타이드의 형성 기작 및 분해에 의한 제거 방법을 알아보기 위하여 카제인 가수 분해물에서 쓴 맛 펩타이드를 분리하여 그 특성을 조사하였다. Bacillus subtilis가 생산하는 염기성 단백부내 효소를 순수 분리된 ${\alpha}_{s1}$-카세인과 ${\beta}$-카제인에 처리하여 카제인 가수 분해물을 만들고, 이 가수 분해물에서 용매 추출, Sephadex G-25 겔 크로마토그래피, 고성능 액체 크로마토그래피를 이용해 쓴 맛 펩타이드를 순수 분리했다. 고성능 액체 크로마토그래피는 역상 칼럼인 octadecylsilica 칼럼을 사용했고, 0.1% TFA와 80% $CH_3CN$의 linear gradient 방법을 이용했다. ${\alpha}_{s1}$-카제인 가수분해물에서 3가지 쓴 맛 펩타이드를 분리하였는데, BP-I은 $CH_3CN$ 34%에서, BP-II는 35%, BP-III는 26%에서 각각 용출되었다. ${\beta}$-카제인 가수 분해물에서 2가지 쓴 맛 펩타이드를 분리했는데, BP-IV는 $CH_3CN$ 40%에서, BP-V는 42%에서 용출되었다. 분리된 다섯 가지 펩타이드 중 BP-V가 가장 소수도가 높았으며, 쓴 맛은 BP-I과 BP-II가 가장 강했다.

• Journal of Microbiology and Biotechnology
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• 제31권8호
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• pp.1163-1174
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• 2021

Casein-derived antioxidant peptides by using microbial proteases have gained increasing attention. Combination of two microbial proteases, Protin SD-NY10 and Protease A "Amano" 2SD, was employed to hydrolyze casein to obtain potential antioxidant peptides that were identified by LC-MS/MS, chemically synthesized and characterized in a oxidatively damaged HepG2 cell model. Four peptides, YQLD, FSDIPNPIGSEN, FSDIPNPIGSE, YFYP were found to possess high 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability. Evaluation with HepG2 cells showed that the 4 peptides at low concentrations (< 1.0 mg/ml) protected the cells against oxidative damage. The 4 peptides exhibited different levels of antioxidant activity by stimulating mRNA and protein expression of the antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), as well as nuclear factor erythroid-2-related factor 2 (Nrf2), but decreasing the mRNA expression of Kelch-like ECH-associated protein 1 (Keap1). Furthermore, these peptides decreased production of reactive oxygen species (ROS) and malondialdehyde (MDA), but increased glutathione (GSH) production in HepG2 cells. Therefore, the 4 casein-derived peptides obtained by using microbial proteases exhibited different antioxidant activity by activating the Keap1-Nrf2 signaling pathway, and they could serve as potential antioxidant agents in functional foods or pharmaceutic preparation.

• Journal of Dairy Science and Biotechnology
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• 제26권1호
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• pp.27-36
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• 2008

This review was written to introduce updated data on the structure and function of the major milk proteins identified as allergens, the characterization of their epitopes in each allergenic milk proteins, and the reduction of milk protein allergenicity. Most mammalian milk protein, even protein present at low concentration, are potential allergens. Epitopes identified in milk proteins are both conformational(structured epitope) and sequential epitopes(linear epitope), throughout the protein molecules. Epitopes on casein and whey proteins are reported to be sequential epitope and conformational epitopes, respectively. Conformational epitopes on whey protein are changed into sequential epitope by heat denaturation during heat treatment. Several methods have been proposed to reduce allergenicity of milk proteins. Most ideal and acceptable method to make hypoallergenic milk or formula, so far, is the hydrolysis of allergenic milk proteins by enzymes that has substrate specificity, such as pepsin, trypsin, or chymotrypsin. Commercial formulas based on milk protein hydrolysate are available for therapeutic purpose, hypoantigenic formula for infants from families with a history of milk allergy and hypoallergenic formula for infants with existing allergic symptoms.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1978년도 추계학술대회
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• pp.207.5-208
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• 1978

Effects of the plant growth regulator (P. G. R.)on the reaction of proteinase, $\gamma-amylase$ and acid phosphatase were investigated, and also were the conditions of production of P. G. R. by Stroptomyces sp. 445. The P. G. R. had no effect on the act ivities of such enzymes in mung bean seedling. But in germinating seed previously treated with P. G. R. it effected the activity of protease in cotyledon. In the conditions of production of P. G. R., the maxim, activity was appeared in shaking cutlure at $30^{\circ}C$ for 5 days, and by the addition of peptone or casein hydrolysate as nitrogen source, soluble starch as carbon source, and sulfur as metal ion.