• KSBB Journal
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• 제10권2호
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• pp.137-142
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• 1995

Sucrose를 탄소원으로 이용할 수 있는 대장균 W 를 A. eutrophus PHA 합성 유전자가 cloning된 높 은 복제수의 plasmid pSYL105로 형질전환하여 단 순배지에서 배양시 $0.21g/\ell$ 의 낮은 PHB 농도를 얻었다. 이에 107}지의 복합질소원을 소량 첨가하여 PHB 합성에 미치는 영향을 살펴 보았다. Tryptone, casamino acids, casein hydrolysate, 혹은 soy bean hydrolysate의 첨가시 PHB 합성 이 10배 이 상 증대되었다. 또한 이때 sucrose로부터의 PHB 수율도 10배 이상 증가하여 이 네 가지 복합질소원 을 척정 농도로 첨가함으로써 sucrose로부터 효과적인 PHB 생산이 가능함을 알았다.

• 한국축산식품학회지
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• 제22권1호
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• pp.87-93
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• 2002

최근 고혈압을 예방하기 위한ACE 저해 펩타이드에 대한 연구는 주로 여러 가지 식품 단백질의 효소 가수분해물로부터 얻어진 펩타이드를 중심으로 이루어지고 있다. 본 연구에서는 케이신을 여러 가지 상업용 단백질분해 효소를 사용하여 ACE저해 효과가 높은 가수분해물 제조시 가수분해 조건이 ACE저해효과에 미치는 영향을 알아보자 하였으며 적정 가수분해 조건을 설정하고자 하였다. ACE 저해효과를 가지는 케이신 가수분해 물을 제조하기 위한 효소 종류, 첨가량 및 가수분해시간은 효소는 Aspergillus oryzae 유래의 promod 192를 사용하고, 효소의 첨가량은 케이신에 대하여 1%, 반응시간은 47$^{\circ}C$에서 12시간으로 하는 것이 적당하였다. 이 때 케이신 가수분해물의 $IC_{50}$/값은 248.71ug/m1(통상법), 265.84ug/ml(전처리법)로서 ACE 저해효과가 높았다.

• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 1999년도 제24회 정기총회 및 프로그램, 제37회 학술발표회 및 특별강연 초록
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• pp.75.1-75
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• 1999

제초제 저항성 형질전환 목초 생산을 위하여 유전자총(Gene-gun) 및 Agrobacterium 기법을 이용하여 형질전환을 시도한 결과를 요약하면 다음과 같다. 1. 공시재료 : 알팔파 (cv. Vernal, Anker), 오차드그라스 (합성19호) 2. 캘러스의 유도 및 증식 : 알팔파 종자를 SH-3 배지 (SH기본배지, 2,4-D 3mg/L 포함) 그리고 오차드그라스 종자를 MS-5 배지 (MS기본배지, 2,4-D 5mg/L, 2g casein hydrolysate 포함)에 치상하여 캘러스를 유도하였다. 유도된 캘러스는 증식을 위하여 SH-3 및 MS-3 배지 (MS기본배지, 2,4-D 3mg/L, 2g casein hydrolysate 포함)에서 2주 간격으로 subculture 하였다.(중략)

• 한국식품영양과학회지
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• 제39권4호
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• pp.587-594
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• 2010

다양한 기능적 특성을 가지는 단백질 가수분해물의 개발을 위하여, casein, ISP, wheat gluten, gelatin의 4종류 단백질 기질을 alcalase, bromelain, papain, neutrase, trypsin 등의 효소를 이용하여 가수분해물을 제조하였다. 각 단백질에 대한 효소 분해과정을 확인하기 위하여 pH-stat 방법을 이용하여 시간에 따른 단백질 가수분해도(DH)를 측정하였고, 단백질 종류와 효소 종류에 의한 쓴맛 정도와 단백질 가수분해물의 용해성을 검토하고자 DH 10%에서 가수분해를 종결짓고, pH 6.5에서 각각의 용해성과 쓴맛을 NSI(nitrogen soluble index) 측정과 관능검사로 비교하였다. 시간에 따른 가수분해도는 단백질에 따라 다양하게 나타났으며, Casein, ISP, wheat gluten, gelatin의 순으로 높게 나타났다. 모든 단백질에서 alcalase의 가수분해도가 가장 높았으며, neutrase, bromelain, papain의 가수분해도는 비슷한 정도를 보였다. 그러나 trypsin의 경우는 casein에서는 매우 높았지만, ISP에서는 가장 낮았다. DH 10%에서 casein은 trypsin 가수분해물이, ISP와 gluten은 brolmelain과 neutrase 가수분해물이, gelatin의 경우 사용된 모든 효소 가수분해물이 쓴맛이 약하고 용해도가 높아 좋은 기질-효소 조합으로 선택될 수 있었다. 따라서 쓴맛이 적고 용해도가 높은 단백질 가수분해물은 가수분해도의 조절과 단백질과 효소 조합의 선택, 단백질 가수분해물의 농도 조절 등으로 얻을 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권1호
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• pp.61-65
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• 2005

The objective of this work was to investigate the nutritional requirements for the growth of Actinomyces sp. 9RCC5 isolated from the rumen of a native goat in Korea. The growth of strain 9RCC5 on the basal medium or the medium minus certain ingredients from the basal medium demonstrated that strain 9RCC5 showed absolute requirement of vitamin B complex mixture, while hemin and volatile fatty acids (VFA) were stimulatory to growth to some extent. The 9RCC5 strain grew well with casein hydrolysate as the sole added nitrogen source. However, neither a complex of 18 amino acids nor ammonium sulfate effectively replaced casein hydrolysate. Vitamins such as riboflavin and pantothenate were essential for growth, while thiamin and biotin were stimulatory. With regard to VFA, the growth was stimulated by acetic acid but inhibited by valeric acid. Relatively large quantities of $Na^+$, $K^+$ and $Ca^{2+}$ were absolutely required for growth. Supplementation of clarified rumen fluid to the basal medium in a range of 0-10% (vol/vol) resulted in an increased rate of growth as well as an increased extent of growth.

• 대한약리학회지
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• 제12권1호
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• pp.57-62
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• 1976

Using modified technique of Schmidt et al, as described previously (Korean J. Pharmacol 9 : 17, 1973), the stomach of female rats were perfused with physiological saline under urethane anesthesia. The acid-secretory response of the perfused stomach to i.v. hypertonic glucose (50%), casein hydrolysate (20%) or saline (6%) solution were studied with or without histamine or methacholine stimulation. A significant decrease of acid secretion from the rat stomach was induced by i.v. hypertonic glucose or saline solution. The histamine-stimulated acid secretion was also decreased by simultaneous administration of the hypertonic glucose or saline. However, methacholine-stimulated acid response was not affected by the hypertonic glucose. Intravenous infusion of 20% casein hydrolysate solution resulted in an increase in acid output from the stomach under histamine stimuli. These results lead to the conclusion that the inhibitory responses of acid secretion due to i.v. hypertonic glucose solution are brought through the effect of histaminergic, not cholnergic mechanism(s) in the gastric secretion.

• Journal of Microbiology and Biotechnology
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• 제21권8호
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• pp.869-873
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• 2011

Most medium formulations for improving culture of entomopathogenic nematodes (EPN) based on protein sources have used enriched media like animal feed such as dried egg yolk, lactalbumin, and liver extract, among other ingredients. Most results, however, showed unstable yields and longer production time. Many of the results do not show the detailed parameters of fermentation. Soy flour, cotton seed flour, corn gluten meal, casein powder, soytone, peptone, casein hydrolysates, and lactalbumin hydrolysate as protein sources were tested to determine the source to support optimal symbiotic bacteria and nematode growth. The protein hydrolysates selected did not improve bacterial cell mass compared with the yeast extract control, but soy flour was the best, showing 75.1% recovery and producing more bacterial cell number ($1.4{\times}10^9$/ml) than all other sources. The highest yield ($1.85{\times}10^5$ IJs/ml), yield coefficient ($1.67{\times}10^6$ IJs/g medium), and productivity ($1.32{\times}10^7$ IJs/l/day) were also achieved at enriched medium with soybean protein.

• 식물조직배양학회지
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• 제24권5호
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• pp.257-262
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• 1997

Brassica와 Raphanus 간에 속간 교잡종을 육성하기 위해서 34개의 교배 조합을 설정한 다음 수분 12일이 경과된 배주를 BA와 GA 1.0 ㎎/L가 첨가된 MS배지에 접종하고 배의 발아율을 조사하였다. BA나 GA 첨가는 배의 발아에 큰 영향을 미치지 않았다. 무 속의 '내병총태'와 '중국청피'를 부계로 교잡한 조합에서 배의 발아율이 낮았으나 갓(Brassica juncea)을 부계로 교잡한 조합에서는 비교적 배의 발아율이 높았다. 이러한 결과는 배주배양시 배지에 첨가한 casein hydrolysate, malt extract, BA, kinetin 및 glutamine이 배의 발아에 미치는 영향보다는 부계나 모계의 교잡조합에 따라 배의 발아율에 상당한 차이가 있다는 것을 의미한다.

• Journal of Nutrition and Health
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• 제30권1호
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• pp.40-47
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• 1997

Dietary peptides have recently received attention regarding their beneficial effects on nutrient metabolism since the caseinphosphoptides obtained from casein hydrolysate are generally believed to enhance the intestinal absorption of Ca. The two experiments were conducted to investigate the effects of various hydrolyzed fractions of gluten on Ca bioavailability. The gluten hydrolysate of dietary components was produced by enzymatic hydrolysis of gluten whereas gluten hydrolysate supernationt and its precipiate resulted from centrifugation. In experiment I, the rats were for 4 weeks fed the 4 kinds of diets containing same amount of nitrogen and calories and diffeing only in the forms of nitrogen sources. The diets were gluten (G), gluten hydrolysat(GH), gluten hydrolysate supernatant(GHS) and gluten hydrolysate precipitatie(GHP). Determination was made for the body weight gain, serum Ca concentration, Ca solubility in small intestinal contents, bone weight, length and stength, bone ash and Ca content, and Ca balance, respectively. No significant difference was noticed as regards growth, serum Ca, and bone dimension and Ca content among rat groups. More significant increase was observed with regard to Ca absorption and intestinal solubility in the rats receiving the GH or GHS diet which containe crude gluten peptides, than in those subjected to G or GHP diet. In experiment II, in vitro determination for Ca solubility was made to ascertain the mechanism responsible for the effects of gluten peptides on Ca absorption. The 10mM Ca in potassium phosphate buffer solution(pH 7.0) incubated for 3 hours at 37$^{\circ}C$ by the GHS fraction, was observed to be capable of increasing the Ca solubility at 5-25mg/ml concentration of gluten peptides. These observations suggest that the gluten peptides from gluten hydrolysate may enhance the Ca absorption efficiency by increasing the solubility of Ca in small intestine.

• 한국축산식품학회지
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• 제36권4호
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• pp.516-522
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• 2016

Goat milk is highly nutritious and is consumed in many countries, but the development of functional foods from goat milk has been slow compared to that for other types of milk. The aim of this study was to develop a goat milk protein hydrolysate (GMPH) with enhanced digestibility and better hypoallergenic properties in comparison with other protein sources such as ovalbumin and soy protein. Goat milk protein was digested with four commercial food-grade proteases (separately) under various conditions to achieve the best hydrolysis of α_s -casein and β-lactoglobulin. It was shown that treatment with alcalase (0.4%, 60℃ for 30 min) effectively degraded these two proteins, as determined by SDS-PAGE, measurement of nonprotein nitrogen content, and reverse-phase high-performance liquid chromatography. Hydrolysis with alcalase resulted in a significant decrease in β-lactoglobulin concentration (almost to nil) and a ~40% reduction in the level of α_s-casein. Quantification of histamine and TNF-α released from HMC-1 cells (human mast cell line) showed that the GMPH did not induce an allergic response when compared to the control. Hence, the GMPH may be useful for development of novel foods for infants, the elderly, and convalescent patients, to replace cow milk.