• Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.36-43
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• 1999

A study on the hydrolysis of anchovy using proteolytic bacteria isolated from anchovy jeotkal (a salt-fermented fish) was carried out to develop a rapid process of liquefied anchovy jeotkal. Five kinds of proteolytic bacteria, such as Staphylococcus sp.-l, Photobacterium sp., Volcaniella sp., Staphylococcus sp.-2 and Bacillus sp., were isolated from the anchovy jeotka1 that fermented with $20\%$ NaCl at room temperature for 2 months. Those grew well at $40^{\circ}C$, pH 7.0 on TPY broth with $2.0\%$ NaCl. The optimal hydrolysis temperature, pH, time and proteolytic bacteria densities for hydrolysis of minced anchovy were$40^{\circ}C$, 7.0, 6 hours and $1.8\times10^8$ cells/g raw anchovy, respectively.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.294-299
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• 1992

This study was to examine the effect of functional properties of soy protein isolate(SPI) and qualities of soybean curd upon proteolytic hydrolysis. SPI was hydrolyzed using proteolytic enzyme, bromelain. The protein content of SPI by microkjeldahl method was 84% and the degree of hydrolysis in modified soy protein isolate(MSPI) was 2.7%. The solubility of MSPI was higher than that of control at various pH tested and proteolytic hydrolysis was increased emulsion formation and foam expansion while decreased emulsion stability, foam stability and calcium precipitation. Modified soybean curdI, standard soybean milk: Modified soybean milk=3:1, was soft and springy soybean curd when the texture properties of soybean curd were tested by texture profile analysis using Instron and sensory evaluation. The rheological model of soybean curds was investigated by stress relaxation test. The analysis of relaxation curve revealed that the rheological behavior of soybean curds could be expressed by 7-element generalized Maxwell model. The equilibrium modulus and modulus of elasticity decreased as the ratio of modified soybean milk was increased.

• 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.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.1
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• pp.1-12
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• 1998

To examine the possibility of protein recycling of shaving scraps containing chromium generated from manufacturing process of leather, the optimum hydrolysis conditions and the withdrawal methods of low molecular weight protein for using the liquid fertilizer sources by investigation of solubilities of hydrolyzed protein, inorganic nutrients contents and molecular weight distributions of hydrolyzed protein from shaving scraps treated with mixed alkaline inducing agents and mixed alkaline proteolytic enzymes including MgO were investigated. In hydrolysis of shaving scraps treated with mixed alkaline inducing agents, the solubility of shaving scraps were clearly different with 65~85% according to the sorts of the inducing agents, and the degree of hydrolysis was high in the order of NaOH, $Ca(OH)_2$ and KOH. The average molecular weights of withdrawal hydrolyzed protein were 10, 40 and 80 KD treated with NaOH, $Ca(OH)_2$ and KOH, respectively. And the chromium contents was about 15 ppm. In hydrolysis of shaving scraps treated with mixed alkaline proteolytic enzymes, the bility of shaving scraps were high in the order of alcalase, esperase and savinase. In c of treating 0.5% alcalase, the low molecular weight of hydrolyzed protein could be withdrawn. The solubility of the hydrolyzed protein was about 85%, the average molecular weight of the protein was below 1 KD and chrome content of the protein was below 10 ppm.

• Journal of Pharmaceutical Investigation
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• v.19 no.4
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• pp.203-212
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• 1989

A proteolytic enzyme was extracted from Sarcodon aspratus (Berk) S. Ito by percolation method. Proteolytic activity of the extracted proteolytic enzyme (SAP) was compared with several digestives containing proteolytic enzymes. Potency of SAP was higher than that of the other digestives except for protease. The optimum pH ranse of SAP was similar to that of pancveatin and protease. SAP was more stable than pancreatin and protease under various temperature, alkaline pH, and metal ions. Bovine serum albumin hydrolysing activity of SAP was equivalent to that of pancreatin and protease in small intestine of rats. SAP demonstrated lower adsorption to antacids than pancreatin and protease. Among the mixtures of SAP and several antacids, magnesium oxide-SAP showed the highest proteolytic activity.

• Journal of the East Asian Society of Dietary Life
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• v.4 no.3
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• pp.87-96
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• 1994

This study was carried out to investigate the effect of hydrolysis by proteolytic enzymes on the functional properties of sesame protein concentrate. Sesame protein concentrate was hydrolyzed with papain, pepsin and trypsin to obtain 10% and 20% degree of hydrolysis. The nirogen solubility in water was increased with increasing the degree of hydrolysis. Bulk density was increased by enzymatic hydrolysis but water absorption capacity was increased only in the case of pepsin-hydrolyzed SPC. Higher fat absorption capacity was found in SPC with 10% DH than SPC with 20% DH. Emulsifying activity was also increased by enzymatic hydrolysis except SPC with 10% DH by papain.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.561-568
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• 2012

The aim of this study was to introduce a simple method for isolation of ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin and bovine serum albumin from cow's milk, and peptides produced by enzymatic hydrolysis of ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin and bovine serum albumin with alcalase. Whey protein were precipitated from whey by ammonium sulfate and, ${\alpha}$-lactalbumin and ${\beta}$-lactoglobulin were isolated using Hi Prep 26/60 Sephacryl S-100 column gel filtration chromatography. Bovine serum albumin and ${\beta}$-lactoglobulin were isolated by Mono-Q 5/50 GL column anion exchange chromatography of the 50% Ammonium Sulfate-supernatant. Isolated whey proteins were hydrolyzed by proteolytic alcalase. Tricine SDS-PAGE and reverse-phase HPLC analyses revealed that almost hydrolyzed all the ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin and bovine serum albumin with alcalase. Molecular weight of various peptides derived from alcalase hydrolysate were small molecular weight than 3.5 kDa.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.873-877
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• 2008

Native soy protein isolate (SPI) was hydrolyzed with 4 different proteolytic enzymes, including bromelain, papain, Neutrase, and Flavourzyme. SPI hydrolysates with the degree of hydrolysis (DH) in range of 6 to 15% were prepared by each enzyme. The angiotensin 1 converting enzyme (ACE) inhibitory and the antioxidant activities of the SPI hydrolysates, such as superoxide dismutase-like activity and inhibition of the linoleic acid autoxidation, were evaluated. Overall, as the DH increased, all evaluated bioactivities of the SPI hydrolysates significantly increased. The significantly highest ACE inhibitory and antioxidant activities were found in hydrolysates made with papain and bromelain, respectively. SPI hydrolysates by Flavourzyme showed the significantly lowest activity in all tested bioactivities. The results suggested that ACE inhibitory and antioxidant activities of SPI hydrolysates were determined by the DH and by the enzyme used.

• Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.174-178
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• 2011

This study aimed to determine the degree of hydrolysis and angiotensin-I-converting enzyme (ACE)-inhibitory activity of Giant Jellyfish Nemopilema nomurai (jellyfish) hydrolysates. The degree of hydrolysis using six proteolytic enzymes (Alcalase, Flavozyme, Neutrase, papain, Protamex, and trypsin) ranged from 13.1-36.8% and the inhibitory activities from 20.46-79.58%. Using papain hydrolysate, we newly isolated and characterized ACE-inhibitory peptides with a molecular weight of 3,000-5,000 Da that originated from jellyfish collagen. The purified peptide (FII-b) was predicted to be produced from an alpha-2 fragment of the type IV collagen of jellyfish. The N-terminal sequence of FII-b was Asp-Pro-Gly-Leu-Glu-Gly-Ala-His-Gly- and showed 87% identity to the collagen type IV alpha-2 fragment of Rattus norvegicus and a predicted protein from Nematostella vectensis, indicating that the ACE-inhibitory peptide originated from the collagen hydrolysate and had an $IC_{50}$ value of 3.8 ${\mu}g$/mL. The primary structure of the fragment is now being studied; this peptide represents an interesting new type of ACE inhibitor and will provide knowledge of the potential applications of jellyfish components as therapies for hypertension.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.5
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• pp.557-568
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• 1995

Proteolytic properties of enzymes from the muscle and viscera of anchovy have been examined. Cathepsin L, chymotrypsin, and trypsin showed similar Km values for casein. However, they had higher Km values for myofibrillar proteins than those for casein. The $k_cat$ of cathepsin L and chymotrypsin for myofibrillar proteins were higher than that of trypsin, and also cathepsin L and chymotrypsin caused higher hydrolysis in myofibrillar proteins of anchovy and yellowtail. In the presence of sodium chloride$(0-25\%)$, proteolytic activity for myofibrillar proteins from yellowtail was higher than that for casein. Proteolytic activity was decreased with the increase of sodium chloride concentration. Cathepsin L had been less affected by NaCl concentration and temperature on the hydrolysis of myofibrillar proteins than chymotrypsin and trypsin. Cathepsin L and chymotrypsin were move responsible to the autolysis of muscle proteins from fish than trypsin.