• Journal of the East Asian Society of Dietary Life
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• v.19 no.1
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• pp.45-51
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• 2009

In this study, food protein hydrolysates were prepared from six types of food protein: purified meat protein, whole egg protein, casein, isolated soy protein, concentrated rice protein, and gluten. Food proteins were hydrolyzed with pepsin and ethanol (80%)-soluble fractions of pepsin hydrolysates were employed for analysis. The products were colorless and odorless powders with low fat content and good solubility. The MW (molecular weight) of the protein hydrolysates was confirmed to be $200{\sim}1,800$ via gel filtration. Free amino acid contents accounted for less than 5% of the samples. The results of our amino acid analysis revealed that all food protein hydrolysates preserved their original amino acid compositions and nutritional values of their source proteins with highly pure oligopeptide mixtures. These results show that the food protein hydrolysates prepared in these investigations should prove excellent dietary nitrogen sources for a variety of applications.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.5
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• pp.519-524
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• 1992

purified rapeseed(Brassica napus var. Youngsan) protein was hydrolyzed by pronase. The hyrolysate protein was investigated for the some physicochemical and functional properties. UV and intrinsic fluorescence spectra of the hydrolysate showed the maximum absorption at 274nm and 360nm respectively. Intensity of yellow color decreased in the process of hydrolysis and the surface hydrophobicity decreased up to fourfold. The main bands of hydrolysate by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) were observed at 14,000 to 12,000 dalton molecular weight. Solubilities of hydrolyzed protein increased by 10~15% compared to those of unhydrolyzed protein at acidic pH. In the hydrolysate, while absorption of both water and oil, foam expansion and emulsion stability were increased, absolute viscosity, heat coagulation, calcium coagulation, foam stability and emulsion activity were decreased.

• Preventive Nutrition and Food Science
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• v.16 no.3
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• pp.248-252
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• 2011

Soy protein based formula (SPF) has been developed for infants who are at a high risk for atopic dermatitis (AD) and cow's milk protein allergy (CMA). We performed this study to evaluate the therapeutic efficacy and safety of SPF compared to conventional hydrolyzed cow's milk formula (hCMF) in the feeding of infants with AD and CMA. 38 infants (12 to 24 months of age) diagnosed with CMA and AD were randomized to receive either SPF or hCMF for 12 weeks. Follow-up was conducted at 4, 8 and 12 weeks. Growth parameters of the infants were evaluated during each visit. Clinical evaluations, including AD severity scores, pruritus, specific immunoglobulin E (IgE) (cow's milk protein and soy protein) levels of peripheral blood, were made at enrollment and week 12. Analysis was performed on the 32 infants (SPF: n=16, hCMF: n=16) who completed the 12-week intervention. Eczema area and severity index (EASI) scores, a measure of the severity of AD, and pruritus were significantly reduced after 12 weeks compared to enrollment in the both groups; however, the median changes for EASI scores and pruritus were not statistically different between the two groups. The growth parameters did not differ significantly between both groups at any assessed time point. This study suggests that SPF could be useful in decreasing the severity of AD without affecting infant growth status. Therefore SPF could provide an adequate and safe alternative to hCMF in treating infants with AD and CMA during the first 12 to 24 months of their life.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.3
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• pp.177-186
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• 2013

Skin dermal fibroblast is the major collagen-producing cell type in human skin. As aging process continues in human skin, collagen production is reduced and fragmentation is increased, which is initiated by matrix metalloproteinase-1 (MMP-1). This imbalance of collagen homeostasis impairs the structure and function of dermal collagenous extracellular matrix (ECM), thereby promoting skin aging. Cysteine-rich protein 61 (CCN1), a member of the CCN family, negatively regulates collagen homeostasis in primary human skin dermal fibroblast cells. It is known in aging fibroblast cells that elevated CCN1 expression substantially reduces type I procollagen and concurrently increases MMP-1, which initiates fibrillar collagen degradation. And proliferation rate of aging fibroblast cells is reduced compared to the pre-aging fibroblast cells. In this study, we confirmed that the replicative senescence dermal fibroblast cells increased the expression levels of MMP-1 and decreased the production of type I procollagen. Our results also showed that the replicative senescence dermal fibroblast cells increased in the expression of CCN1 and decreased in the proliferation rate. Hydrolyzed Ulva pertusa extracts are the materials to improve photo-aging by reducing the expression of MMP-1 that was increased by ultraviolet and by promoting the synthesis of new collagen from fibroblast cells. In this study, we also investigated the hydrolyzed U. pertusa extract to see whether it inhibits CCN1 protein expression in the senescence fibroblasts. Results showed that the hydrolyzed U. pertusa extract inhibited the expression of MMP-1 and increased the production of type I procollagen in the aging skin fibroblast cells cultured. In addition, the proteins that regulate collagen homeostasis CCN1 expression were greatly reduced. The hydrolyzed U. pertusa extract increased the proliferation rate of the aging fibroblast cells. These results suggest that replicative senescent fibroblast cells may be used in the study of cosmetic ingredients as a model of the natural aging. In conclusion, the hydrolyzed U. pertusa extract can be used in anti-wrinkle functional cosmetic material to improve the natural aging skin care as well as photo-aging.

• Preventive Nutrition and Food Science
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• v.15 no.4
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• pp.282-286
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• 2010

To isolate a calcium-binding peptide from chlorella protein hydrolysates, chlorella protein was extracted and hydrolyzed using Flavourzyme, a commercial protease. The degree of hydrolysis and calcium-binding capacity were determined using trinitrobenzenesulfonic acid and orthophenanthroline methods, respectively. The enzymatic hydrolysis of chlorella protein for 6 hr was sufficient for the preparation of chlorella protein hydrolysates. The hydrolysates of chlorella protein were then ultra-filtered under 5 kDa as molecular weight. The membrane-filtered solution was fractionated using ion exchange, reverse phase, normal phase chromatography, and fast protein liquid chromatography to identify a calcium-binding peptide. The purified calcium-binding peptide had a calcium binding activity of 0.166 mM and was determined to be 700.48 Da as molecular weight, and partially identified as a peptide containing Asn-Ser-Gly-Cys based on liquid chromatography/electrospray ionization tandem mass spectrum.

• Food Engineering Progress
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• v.15 no.1
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• pp.41-47
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• 2011

The defatted rice bran (DRB) was enzymatically hydrolyzed using eight commercial proteases for 4hr at optimum pH and temperature. Proteolytic hydrolysates were examined in supernatant and precipitate using lowry, semimicro kjeldahl and gravimetric method using weight difference before and after enzymatic hydrolysis. In lowry and kjeldahl protein assay method, two proteases (Alcalase and Protease N) were found to be the most effective enzymes. In gravimetric method, 60.6~118.3 mg protein/g DRB was hydrolyzed after eight commercial proteases treatments. Similar to lowry and kjeldahl method, 118.3 and 107.1 mg protein/g DRB were hydrolyzed after Alcalase and Protease N treatments, respectively. When two or three effective proteases (Protamex, Alcalase and Protease N) were applied at one time to obtain synergistic effect, significant increase (P<0.05) was observed when three proteases were applied at one time (63.4 mg protein/g DRB in lowry method and 204.5 mg protein/g DRB in gravimetric method). This result suggests that Alcalase and Protease N were the most effective enzymes for proteolysis of DRB and three commercial enzymes (Protamex, Alcalase and Protease N) showed the synergistic effect on the hydrolysis of DRB.

• Journal of the Korean Wood Science and Technology
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• v.45 no.1
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• pp.126-138
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• 2017

This study was conducted to investigate the potential of chicken feather (CF), which is a by-product in poultry industry, as a raw material of wood adhesives. For the purpose, adhesive resins were formulated with NaOH- and $H_2SO_4$-hydrolyzed CF as well as crosslinkers, and then the properties and water resistance of the adhesive resins against hot water were measured. CF was made of mainly keratin-type protein, and no or very low content of heavy metals was detected. Hydrolysis rate of CF increased as NaOH concentration in hydrolysis solutions increased. However, in order to minimize the loss of adhesive property of protein itself by the severe hydrolysis of CF and to seek its proper hydrolysis conditions, NaOH concentrations in hydrolysis solution determined to adjust to 5%, 7.5% and 10%. In the NaOH-hydrolyzed CF, $H_2SO_4$-hydrolyzed CF as a hardener and crosslinker were added to formulate CF-based adhesive resins. Solid content of the resins ranged from 28.3% to 44.8% depending on hydrolysis conditions and type of crosslinker. Viscosity of the resins at $25^{\circ}C$ was very high. However, when the temperature of the resins was increased to $50^{\circ}C$, the viscosity decreased greatly and thus the resins could be applied as a sprayable resin. Retention rate measured to evaluate the water resistance of adhesive resins was the highest in the cured resin formulated with 5% NaOH-hydrolyzed CF and 5% $H_2SO_4$-hydrolyzed CF of 10% based on the solid weight as a hardener. Retention rate depending on crosslinkers added into adhesive resins was the highest phenol-formaldehyde (PF) followed by melamine-urea-formaldehyde (MUF) and formalin. The retention rate of CF-based adhesives formulated with 5% NaOH-hydrolyzed CF, PF and $H_2SO_4$-hydrolyzed CF of 10% and over did not differ statistically from that of commercial MUF resins. All of CF-based adhesives formulated with PF as a crosslinker and one with 5% NaOH-hydrolyzed CF of 55%, 5% $H_2SO_4$-hydrolyzed CF of 15%, and MUF of 30% on the basis of solid weight could be substituted for commercial urea-formaldehyde resins, From the results, CF can be used as a raw material of wood adhesives if hydrolyzed in proper conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.6
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• pp.725-731
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• 1998

Nine crossbred female pigs fitted with the bladder catheters were used to investigate the effects of dietary protein form on the efficiency of absorbed nitrogen for nitrogen retention in growing pigs. Combinations of the main protein sources were corn-soybean meal (CSM; slow + slow absorption rate form), corn-hydrolyzed casein (CAS; slow + rapid absorption rate form) and corn-porcine plasma (CPL; slow + intermediate absorption rate form). All experimental diets were formulated to be isonitrogenous (CP 11%) and isocaloric (3.5 Mcal/kg) and synthetic amino acids were added to the diet as required to maintain an equivalent amino acid profile among diets. Fecal digestibility of nitrogen was not different among treatments (p > 0.10). Ingested nitrogen was absorbed with an apparent efficiency of 82% to 84%. Mean nitrogen retention in pigs fed the CSM diet was as high as for pigs fed the CPL diet (0.74 g N/kg $BW^{0.75}$ per d), which was higher than the N retention rate in pigs fed CAS diet (0.68 g/kg $BW^{0.75}$ per d; P < 0.05). Apparent biological values (ABV = 100 ${\times}$ N retention/absorbed nitrogen) were 63.3%, 58.0% and 61.6% for CSM, CAS, and CPL groups, respectively (p < 0.05). There was no difference in mean energy digestibility among treatments. The efficiency of absorbed lysine utilization was significantly different among treatments (p < 0.05). Pigs fed the CAS diet were inferior to counterparts on the other diets in utilizing absorbed lysine. The ratios of free (and small peptide-bound) to protein-bound amino acids in CSM diet differed considerably from the CAS diet. This may affect the efficiency of amino acids utilization for nitrogen retention if hydrolyzed and intact amino acid pools reach the blood at different times.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1125-1130
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• 1997

The effects of enzyme combination, pH, acid washing and enzyme treatment sequence were investigated in the hydrolysis of soy protein. Comparing Alcalase vs. Neutrase/Alcalase, it appeared that Neutrase/Alcalase was more efficient than Alcalase alone, as the highest degree of hydrolysis (DH) was seen in Neutrase/Alcalase. A surprisingly high DH (more than 60%) was observed with Flavourzyme in the second hydrolysis. The separation of insolubles from the first hydrolysis had little effect on the second hydrolysis. When the washing water from the first hydrolysis was reused in the next hydrolysis, the DH and protein recovery were increased. The addition of calcium ion showed not so much positive effects by the stabilization of Neutrase on the Protein hydrolysis. The use of carbohydrase and repeated acid washing gave positive effects on DH. The simultaneous treatment using endoprotease and exoprotease with pH adjustment improved DH significantly.

• Journal of Dairy Science and Biotechnology
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• v.34 no.2
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• pp.137-144
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• 2016

The ultimate research goal of the current study was a development of hydrolyzed whey protein powder (7%-GNANA) manufactured with normal content of sialic acid, a marker compound, that is naturally occurring at 7% concentration in GMP obtained from the milk protein. GMP is a safe food, used worldwide in infant and baby foods, etc. The test substance was prepared using (7% sialic acid containing) GMP as a raw material, and then using alcalase, an enzyme approved as a food additive, after separation of sialic acid with 100% efficiency and 7%-GNANA (containing 7% sialic acid and protein; product name: HELICOBACTROL-7) provided by MEDINUTROL Inc. (Korea). Bacterial reverse mutation (Ames) test was conducted in accordance with GLP Guideline using the test substance specified above. To identify its mutagenic potential against microorganisms, histidine auxotrophic strains of Salmonella Typhimurium, TA98, TA100, TA1535, and TA1537, and tryptophan auxotrophic strain of Escherichia coli, WP2uvrA, were used. The bacterial reverse mutation (Ames) test was performed by dividing the test substances into five different concentration groups (0, 61.7, 185, 556, 1,670, $5,000{\mu}g/plate$). Results of this experiment did not reveal repetitive increase of colony generating values or positive criteria for reverse mutagenicity for any concentration of test substances in any of the five strains, regardless of the presence of a metabolic activation system, and no dose-dependency was identified. In conclusion, the safety of 7%-GNANA test substance was verified by bacterial reverse mutation test conducted before registration of 7%-GNANA as a food additive.