• 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.

• Journal of Life Science
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• v.8 no.2
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• pp.119-125
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• 1998

Column-purified double-stranded RNA binding factor (RBF) protein was tested for its binding affinity for the different forms of nucleic acids structure such as single-stranded(ss) and double-stranded(ds)RNA and ss- and dsDNA. The RBF protein was incubated with each of these nucleic acid structures in separate reactions and its comparative binding affnity was visualized by SDS-polyacrylamide gel electrophoresis. The RBF protein bound to the dsRNA molecule to form a tight RNA:protein complex in agreement with previous studies, but not to the other nucleic acid molecules confirming its distinctive affinity for the dsRNA structure. In phosphorylation assay in vito, the purified RBF protein significantly inhibited the autophosphorylation of the PKR derived from not only human but mouse source in the presence of poly(I):poly(C). It is suggesting that PKR vs. RBF is similarly under a competitive interaction among different eukaryotic organisms during protein synthesis.

• Korean Journal of Food Science and Technology
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• v.18 no.3
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• pp.204-209
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• 1986

The functional properties of defatted silkworm larvae flour and protein concentrate have been compared with those of soybean. The protein contents of soybean and silkworm larvae protein concentrate were 70.3% and 84.1%, respectively. The solubility of silkworm larvae protein concentrate was lower than that of soybean protein at various pH tested. However, silkworm larvae protein concentrate showed better fat absorption, poorer water absorption and overall higher bulk density than soybean protein. The silkworm larvae protein concentrate showed higher emulsifying capacity and stability, but showed lower foaming capacity and stability than soybean protein. Silkworm larvae protein concentrate showed highest viscosity among various protein products at all concentrations and reached the highest viscosity at 5${\sim}$7% protein concentration. Therefore, high emulsification properties of silkworm larvae protein concentrate will be a good protein source when it is added to emulsified food.

• Journal of the Korean Society of Industry Convergence
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• v.20 no.5
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• pp.441-446
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• 2017

Among the many foods, it is hard to find perfect food with nutrition and functionality like beans. Korean food culture is the main ingredient of korean culture, kochujang, soybean paste, and soy sauce, and processed soybean tofu is the main ingredient. Soybean meets high quality protein and fat, and it has excellent results in prevention and treatment of all kinds of diseases. Soybean food is becoming a new generation health food. In countries where animal protein intake is low, soybean is used as a protein source instead of animal protein. Tofu, a processed food, is a complete food with high digestibility. In order to publicize the superiority of soybean nutritional value, Tofu processing and powder were investigated by observing the size, shape and characteristics of bean powder using domestic soybeans and imported soybean, and the variation of the amount of coagulant.

• Korean Journal of Microbiology
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• v.25 no.1
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• pp.52-56
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• 1987

The evidences that Lam B protein of E. coli is used as a receptor for infections of bacteriophage N4 as well as bacteriophage lambda were obtained from the following experimental results. First, all of the isolated lambda resistant dlones possessing foreign DNA fragments in the plasmids were also resistant to bacteriophage N4, but not to bacteriophage $\phi$ 80, T4 and T7. Second, when the plasmid DNA was treated with various restriction enzymes and ligated to delete the total or a portion of the foreign DNA fragments, the deleted plasmids lost the resistant activities to lambda and N4, simultaneously. Third, after amplification of Lam B protein about 200 times by inducing the protein using maltose as a sole carbon source, the host E. coli became sensitive to both lambda and N4.

• Food Science of Animal Resources
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• v.44 no.2
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• pp.299-308
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• 2024

Proteins in whey have prebiotic and antimicrobial properties. Whey protein comprises numerous bioactive proteins and peptides, including glycomacropeptide (GMP), a hydrophilic casein peptide that separates with the whey fraction during cheese making. GMP has traditionally been used as a protein source for individuals with phenylketonuria and also has prebiotic (supporting the growth of Bifidobacterium and lactic acid bacteria) and antimicrobial activities. GMP supplementation may help positively modulate the gut microbiome, help treat dysbiosis-related gastrointestinal disorders and improve overall health in consumers.

• The Korean Journal of Food And Nutrition
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• v.4 no.2
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• pp.175-186
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• 1991

The purpose of this study is to provide useful information which will aid in the promotion of nutritional policy in the Korean rural area which are derived from a survey of intake and source of protein in some Korean rural adults and the correlations between their protein nutrition and various nutrients, the uses of tobacco, alcohol, coffee, etc. The survey was conducted from July, 24 through July, 18, 1989. The healthy subjects were 45 males(average age 42.3, average BMI 22.1kg/m2) and 55 females (44 years, 21.2 kg/m2) residing in Sungjoo Kyun, Chulanam-Do, Korea. The subjects were examined for the anthropometric, food Intake and food habits. Their daily diets were measured by 24-hr recall method. The results can be summarized as follows : The daily mean protein intakes of male and female subjects were 9595 of RDA(66, 5g) (16. 7% of total food intake per day) and 102.3Bh of RDA(61g) (14.8% of total intake per day) respectively. The order of sources of animal protein in all subjects was fish(47.9%), meat(29.8%), milk (12%), and egg(10.3%). Among protein sources the intake frequencies of fork and chicken were higher than those of others. The protein nutrition of the subjects showed positive correlations with energy and fat, carbohydrate, fiber at the level of significance of 1%. The protein nutrition of the male subjects showed no correlation with age, BMI, uses of alcohol, coffee, medicine, but the plant protein nutrition showed a positive correlation with smoking and exercise(at 5%). And the protein nutrition of the male subjects showed no correlations with uses of tobacco, alcohol, coffee, medicine and their opinion of their present state of their health, but the age of the male subjects showed negative correlations with milk(at 1%) and egg(at 5%). In conclusion, the daily protein Intake was good and the main sources of animal protein were fishes in rural adults. The protein nutrition of the subjects showed a correlation with energy, fat, carbohydrate and in the case of female, milk and egg intakes showed the negative correlation with age.

• Food Science of Animal Resources
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• v.44 no.3
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• pp.723-737
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• 2024

Yeast protein can be a nutritionally suitable auxiliary protein source in livestock food. The breakdown of proteins and thereby generating high-quality peptide, typically provides nutritional benefits. Enzyme hydrolysis has been effectively uesed to generate peptides; however, studies on the potential applications of different types of enzymes to produce yeast protein hydrolysates remain limited. This study investigated the effects of endo- (alcalase and neutrase) and exotype (flavourzyme and prozyme 2000P) enzyme treatments on yeast protein. Endotype enzymes facilitate a higher hydrolysis efficiency in yeast proteins than exotype enzymes. The highest degree of hydrolysis was observed for the protein treated with neutrase, which was followed by alcalase, prozyme 2000P, and flavourzyme. Furthermore, endotype enzyme treated proteins exhibited higher solubility than their exotype counterparts. Notably, the more uniform particle size distribution was observed in endotype treated yeast protein. Moreover, compared with the original yeast protein, the enzymatic protein hydrolysates possessed a higher content of β-sheets structures, indicating their higher structural stability. Regardless of enzyme type, enzyme treated protein possessed a higher total free amino acid content including essential amino acids. Therefore, this study provides significant insights into the production of protein hydrolysates as an alternative protein material.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.817-823
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• 2000

Four groups of six growing gilts each were fed ad libitum diets composed of cereals and soyabean (SBM) or rapeseed (RSM) meal and containing two levels of crude protein: high - 18.0% (RSM-H) and 16.9% (SBM-H) or low - 15.6% (RSM-L) and 15.1% (SBM-L). The diets were balanced by supplementation with crystalline amino acids and contained apparent ileal digestible lysine, methionine, threonine and tryptophan in proportions (1.00:0.32:0.57:0.18) according to CVB (1995). Voluntary feed intake, weight gain and slaughter and chemical body composition of animals were assessed. Protein and energy balances from 25 to 70 kg body weight were calculated by the comparative slaughter method. Protein source had a significant effect on voluntary feed intake; it was 0.12 kg/d lower in pigs fed the SBM than RSM-diets. Pigs fed on the SBM-L diet consumed the least amount of feed (2.17 kg). Daily gain (average, $900{\pm}12.59g$) and feed conversion ratio ($2.54{\pm}0.04kg/kg$) were not statistically affected by source (SMB and RSM) and protein level (high and low). In empty body similar amounts (g/kg) of protein (163 g), water (635 g) and ash (28 g) were found. However, pigs fed the RSM-L diet were fatter than those fed the SBM-L diet (188 vs. 161 g/kg). No statistical differences were observed in daily protein deposition, which on average amounted to $142{\pm}11g$, or carcass characteristics. An improvement of crude protein utilization by 6.3 percentage units was found by decreasing the protein concentration in the diets. Heat production in the body was not significantly affected by the treatments.

• Journal of Korean Society of Water and Wastewater
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• v.35 no.6
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• pp.405-415
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• 2021

MMBR system has been suggested as a promising system to resolve harvesting problems induced from low settling efficiency of microalgae. And recently, a lot of research on reducing fouling at the MMBR system has investigated focused on EPS in many cases. EPS of microalgae mainly consists of polysaccharides and protein components, and is produced through photosynthesis and nitrogen-carbon metabolic pathways. Especially, P-EPS is one of major compounds which occur membrane fouling phenomenon, as its hydrophobic protein components cause floc formation and cake layer accumulation. And it is already known that almost every microalgae can metabolize P-EPS or Chl-a when nitrogen sources as a substrate is insufficient or exhausted situation. With the above backgrounds, uptake rates of P-EPS or Chl-a by Scenedesmus quadricauda according to the type of carbon source and nitrogen concentration were evaluated in order to verify correlation between carbon source vs P-EPS production, and indeed Scenedesmus quadricauda uses P-EPS or Chl-a when the amounts of nitrogen sourc es in the feed is not satisfied. As a result, it was shown that P-EPS and Chl-a production were increased proportional to nitrogen concentration under organic carbon condition. And especially, the amo unts of P-EPS and Chl-a in the cell were diminished with the nitrogen source becomes insufficient or exhausted. Because P-EPS accelerates fouling at the MMBR system, P-EPS degradation by Scenedesmus quadricauda in order to get nitrogen source may contribute to reducing fouling. About a affects of N-consumed Chl-a to the MMBR fouling, more survey is needed. On the contrary, considering the purpose of MMBR system of this study, i.e. harvesting useful high value microalgae efficiently feeding adequate industrial process wastewater, it seems like difficult to maintain satisfied metabolic activity and to harvest with high yield rate using nitrogen-poor MMBR feed.