• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.234-240
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• 1990

Attempts have been made to optimize the hydrolysis conditions of the oyster and the mussel by the commercial proteolytic enzymes. Raw materials were digested with seven different commercial enzymes, and their quality parameters measured in terms of degree of hydrolysis and content of free amino nitrogen, nucleic acid-related substances. and free amino acids as well as sensory evaluation of optimization of their hydrolysis conditions. As a result, following enzymes have been disclosed as effective for enzymatic digestion: MKC-HT proteolytic, alcalase 0.6L and thermease for the oyster whereas MKC-acid fungal protease and thermoase for the mussel, respectively.

• 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.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.451-453
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• 2002

Alkali treatment following acidic hydrolysis (ATAH) of defatted soybean is currently used to reduce the level of 3-chloropropane-1,2-diol (3-MCPD), a known carcinogen, in commercial Korean soy sauce. 3-MCPD concentrations in commercial soy sauces made by ATAH were compared with those made only by acidic hydrolysis, and products that combine soy sauce made by acid hydrolysis (followed by alkalinization) and enzymatic methods. The four soy sauces made by ATAH had lower 3-MCPD concentrations (below 0.078 ppm) than 4 commercial products (0.147∼0.481 ppm) made only by acidic hydrolysis. On the other hand, 3-MCPD concentrations in 4 commercial products made by combining soy sauces made enzymatically with that made from acid (with alkali treatment)-hydrolyzed soybean protein in varying ratios were in a range of 0.016∼0.053 ppm. The 3-MCPD concentrations in commercial Korean soy sauces, with the exception of 2 of the soy sauces made only by acidic hydrolysis, were lower than allowable limit of 0.3 ppm in Korea. These results demonstrated that currently produced commercial soy sauces on the Korean market hate toxicologically save 3-MCPD concentrations. It is also provides evidence that ATAH is an effective process for reducing 3-MCPD concentrations in commercial soy sauce.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.232-234
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• 2002

Bacillus cereus secretes a nonspecific phospholipase C (PLC) that catalyzes the hydrolysis of phospholipids to yield diacylglycerol and a phosphate monoester. This study focuses on the production of PLC by B. cereus and recombinant E. coli with fusion protein gene (plc::gfp). Fermentation processes have been monitored by a 2-dimensional fluorescence sensor.

• BMB Reports
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• v.37 no.1
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• pp.59-74
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• 2004

The study of whole patterns of changes in protein expression and their modifications, or proteomics, presents both technological advances as well as formidable challenges to biological researchers. Nutrition research and the food sciences in general will be strongly influenced by the new knowledge generated by the proteomics approach. This review examines the different aspects of proteomics technologies, while emphasizing the value of consideration of "traditional" aspects of protein separation. These include the choice of the cell, the subcellular fraction, and the isolation and purification of the relevant protein fraction (if known) by protein chromatographic procedures. Qualitative and quantitative analyses of proteins and their peptides formed by proteolytic hydrolysis have been substantially enhanced by the development of mass spectrometry technologies in combination with nanoscale fluidics analysis. These are described, as are the pros and cons of each method in current use.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.519-523
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• 1992

The patterns on the proteolysis of mussel protein using a commercial enzyme preparation were investigated. The best one among six commercial enzyme preparations for the manufacture of mussel extract was Corolase PP, based on the degree of hydrolysis (DH). When the raw mussel paste, without water addition, was adjusted to pH 6.5, added 0.1% (w/w dry basis) of Corolase PP. and reacted at $50^{\circ}C$ for four hours, it reached the maximum value of DH (79%). The precooking of raw mussel decreased the efficiency of extraction and hydrolysis of the protein, due to the inactivation of the autolytic enzymes contained in the mussel. During the course of proteolysis, major free amino acids such as glycine, alanine, glutamic acid and lysine, representing a characteristic brothy taste of mussel were replaced with free hydrophobic amino acids including valine, methionine, isoleucine, and leucine. The electrophoretic pattern and HPLC-GPC pattern of mussel protein hydrolysates during the hydrolysis were observed and also discussed.

• Journal of Animal Science and Technology
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• v.52 no.5
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• pp.435-440
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• 2010

Whey protein concentrate (WPC) is widely used to increase the nutritional and functional properties of food. In this study, the physiochemical and functionality of WPC-30 hydrolysates were examined to evaluate the possibility of application in the food industry. The WPC-30 was manufactured using ultrafiltration and spray-drying, and then hydrolyzed with proteolytic enzyme including alcalase, flavourzyme, nuetrase and protamex. Enzymatic hydrolysis had a significant influence on the physicochemical properties as evident from the increased foaming capacity, solubility. Alcalase caused highest protein hydrolysis (3.26%) and the bitterness. Foaming capacity was largest in WPC-30 hydrolysate treated with flavourzyme. Protein solubility at various levels of pH was highest in protamex-treated WPC-30 hydrolysate. However, the solubility of WPC-30 hydrolysates was significantly improved in alkaline condition than in acidic and neutral conditions. The study revealed that spray dried enzyme modified WPC can be used in various functional food.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.136-140
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• 2008

In order to utilize the silkworm larvae (Bombyx mori) protein, defatted silkworm protein was hydrolysed by four enzymes (pepsin, trypsin, neutrase and alcalase) at various hydrolysis times (6, 12, 18, 24 and 30 hr) and suspension concentrations (2, 5, 10, 15 and 20%). Protein solubility index, ACE (angiotensin converting enzyme) inhibitory activity and antioxidative activity of silkworm protein hydrolysates were investigated. The optimum condition of hydrolysis was 10% suspension concentration and 18 hr. Protein solubility index of trypsin treatment was higher than other enzyme treatments. ACE inhibitory activity and $IC_{50}$ value of antioxidative activity of neutrase treatment were 86.16% at $100\;{\mu}g/mL$ and $352.75\;{\mu}g/mL$, respectively; also, these values were higher than other enzyme treatments.

• Applied Biological Chemistry
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• v.42 no.1
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• pp.49-57
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• 1999

Enzymatic hydrolysis with tuna pyloric caeca crude enzyme(TPCCE) was performed to recover a protein hydrolysate from hoki frame, fish processing by-product. Optimum hydrolytic conditions were pH 10.0, temperature $50^{\circ}C$, and incubation time 12 hrs, and then the degree of hydrolysis was about 60%. The yield of the hydrolysate from hoki frame by enzymatic hydrolysis was approximately 77% on a dry weight basis. The prepared protein hydrolysates were also fractionated through a series of 30, 10, 5 and 1 kDa molecular weight cut-off (MWCO) membranes in order to investigate the effect of their functionalities according to the difference of their molecular size. As the result of studying functionalities of the hydrolysates, 1 K hydrolysate showed the highest solubility over all pHs, and 30 and 10 K hydrolysate showed more excellent emulsifying property and whippability than the other hydrolysates.

• Journal of Microbiology and Biotechnology
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• v.33 no.4
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• pp.511-518
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• 2023

The use of dietary protein products has increased with interests in health promotion, and demand for sports supplements. Among various protein sources, milk protein is one of the most widely employed, given its economic and nutritional advantages. However, recent studies have revealed that milk protein undergoes fecal excretion without complete hydrolysis in the intestines. To increase protein digestibility, heating and drying were implemented; however, these methods reduce protein quality by causing denaturation, aggregation, and chemical modification of amino acids. In the present study, we observed that Lacticaseibacillus rhamnosus IDCC 3201 actively secretes proteases that hydrolyze milk proteins. Furthermore, we showed that co-administration of milk proteins and L. rhamnosus IDCC 3201 increased the digestibility and plasma concentrations of amino acids in a high-protein diet mouse model. Thus, food supplementation of L. rhamnosus IDCC 3201 can be an alternative strategy to increase the digestibility of proteins.