• KSBB Journal
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• v.10 no.2
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• pp.137-142
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• 1995

When Escherichia coli W, which is able to utilize sucrose as a carbon source, harboring a high-copy-number plasmid (pSYL105) containing the Alcaligenes eultrophus polyhydroxyalkanoate(PHA) biosynthetic genes was cultured in a defined medium, the final poly(3-hydroxybutyric acid), PHB, concentration obtained was as low as $0.21g/\ell$. Ten different complex nitrogen sources were, therefore, examined for their ability to enhance PHB synthesis when supplemented to a defined medium. Addition of tryptone, casamino acids, casein hydrolysate, or soy bean hydrolysate enhanced PHB synthesis most significantly, resulting in more than 10 times higher PHB concentration compared with that obtained in a defined medium. Furthermore, PHB yield on sucrose was also increased by more than a 10 fold by the addition of these complex nitrogen sources, which suggested that PHB might be efficiently produced by the recombinant E. coli W(pSYL105) using sucrose as a carbon source.

• Food Science of Animal Resources
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• v.22 no.1
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• pp.87-93
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• 2002

Angiotensiri-I converting enzyme(ACE) catalyst the removal of the C-terminal dipeptide from the angiotensin-I to give the angiotensin-II, a potent peptide that causes constriction of regulation of blood pressure. Recently, ACE inhibitor peptides have been isolated from enzymatic digests of food protein. The aim of this study was to identify bovine casein hydrolysates with ACE inhibitory properties in different enzymatic hydrolysis conditions. The casein were hydrolyzed neutrase, alcalase, protamax, flavourzyme, premed 192, sumizyme MP, sumizyme LP and pescalase alone and with an enzyme combination. Premed 192 produced ACE inhibitory peptides most efficiently. In order to ACE inhibitory peptide produced enzymatic hydrolysis condition were premed 192 added to casein ratio of 1:100(w/w), and incubated at 47$\^{C}$ for 12hrs. Casein hydrolysate gave 50% inhibition(IC$\_$50/ value) of ACE activity at concentration with 248ug/ml(general method) and 265ug/ml(pretreatment method) respectively.

• Proceedings of the Korean Society of Grassland Science Conference
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• 1999.06a
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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)

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.587-594
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• 2010

To develop commercially available food protein hydrolysates, the effects of different types of enzymes and substrates on bitterness and solubility of partially hydrolyzed food proteins were investigated. Four types of proteins (casein, isolated soy protein (ISP), wheat gluten, and gelatin) and five types of proteolytic enzymes (a microbial alkaline protease (alcalase), a microbial neutral protease (neutrase), papain, bromelain, trypsin) were used. To profile the pattern of hydrolysis, the degree of hydrolysis (DH) were monitored during 180 min of reaction time by pH-stat method. Casein showed the highest susceptibility to hydrolysis for all five proteases compared to those of ISP, gluten, and gelatin. In addition, the bitter intensity and solubility (nitrogen soluble index, NSI) of each protein hydrolysate were compared at DH 10%. Bitterness and solubility of protein hydrolysates were highly affected by DH and the types of enzymes and substrates. At DH=10%, casein hydrolysate by trypsin, ISP and gluten hydrolysates by either bromelain or neutrase, and gelatin hydrolysates by the five proteases tested in this study were highly soluble and less bitter.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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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.

• The Korean Journal of Pharmacology
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• v.12 no.1
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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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• v.21 no.8
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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.

• Korean Journal of Plant Tissue Culture
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• v.24 no.5
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• pp.257-262
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• 1997

Intergeneric crosses over 34 cross combinations between genus Brassica and Raphanus were made. Ovules taken out of crossed were cultured on MS media supplemented with 1.0 mg/L GA and BA. Germination of embryo from ovule culture was not influenced by BA and GA in medium but by parental characters in its cross combination. Use of Raphanus sativus cv. Daibyosobudore and Jungkukcheongpi showed low embryo germination when they were used as male part. Cross combination with Brassica juncea as male parent showed slightly increased germination compared to other cross. These results indicated that embryo germination in ovule culture was not much influenced by casein hydrolysate, malt extract, BA, kinetin and glutamine in the medium, but parents in combination were key factor for increasing embryo germination.

• Journal of Nutrition and Health
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• v.30 no.1
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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.

• Food Science of Animal Resources
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• v.36 no.4
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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.