• Journal of Life Science
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• v.11 no.2
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• pp.138-143
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• 2001

Marsh calm(Corbicular elatior)with a short-term storage in raw and a law-rate of utilization has been increasing the needs to develop new marsh calm processing products for a temporary mass treatment and long-term distribution, Therefore the processing conditions of marsh calm beverage using proteolytic enzyme hydrolysis were investigated. A partial hydrolysis at 6$0^{\circ}C$ for 1 hour after adding 3% Alcalase as more effective than a hot water extraction to develop taste compounds from the marsh calm. The result of ommission test showed that nucleotides and their related compounds were contributed in the taste of the marsh calm hydrolysates rather than free amino acids. The taste of the hydrolysates was produced by association with these compounds rather than only one compound s the hydrolystes taste differently for the control when one of these compound was omitted. The hydrolysates were fractionated to molecular weight below 500 dalton to eliminate bitter taste and to improve it flavor from the hydrolysates, 0.05% bay leaf was more effective to improve the odor than other herbs.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.392-397
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• 1996

To produce low salt fermented anchovy by an accelerated method with Asp. oryzae and Bacillus sp. koji, enzyme activity and variation of microflora during the 60 day fermentation were examined. Bacterial counts changed a little during the fermentation with the highest on day 40 for proteolytic and anaerobic bacteria and on day 20 for aerobic bacteria. Proteolytic, lipolytic, aerobic, and anaerobic bacteria counts were higher in the Bacillus sp. koji added anchovy paste than in others. The protease and lipase activities reached the highest point on day 20 and 30, respectively, and decreased gradually afterwards. The protease activity was higher in Asp. oryzae koji than in bacillus sp. koji, but the lipase activity was to the contrary.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.730-736
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• 1995

The solubilization and proteolytic process of $\delta $-endotoxin was analvsed to compare the biochemical property of the toxin isolated from B. thuringiensis subsp. sotto. The purified crystals were dissolved in 50 mM carbonate buffer containing 10 mM dithiothreitol at pH 10 for various times. The electrophoretic pattern showed that a rapid disappearance of 138 kDa protein band. This disappearance of protein with high molecular weight was accompanied by the appearance of new protein fragment with 104 kDa, 60 kDa, and 25 kDa. For proteolvtic processing, the soluble crystals were digested with trypsin for various times. The soluble crystal protein of 104 kDa was completely disappeared. However, the protein fragment of 60 kDa and 25 kDa still remained after complete proteolysis. The comparative immunoblot analysis showed that the antiserum against intact crystals showed strong immunoreactivity to the homologous inclusion protein of 138 kDa, 104 kDa, and 25 kDa, and to the intact spores of 221 kDa and 138 kDa, but not to the vegetative cell homogenate. The sera against crystals and spores had no immunoreactivity to the vegetative cell homogenate.

• Journal of Animal Science and Technology
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• v.65 no.1
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• pp.32-56
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• 2023

This review explores the factors that improve meat protein digestibility and applies the findings to the development of home meal replacements with improved protein digestion rates in older adults. Various methods improve the digestion rate of proteins, such as heat, ultrasound, high pressure, or pulse electric field. In addition, probiotics aid in protein digestion by improving the function of digestive organs and secreting enzymes. Plant-derived proteases, such as papain, bromelain, ficin, actinidin, or zingibain, can also improve the protein digestion rate; however, the digestion rate is dependent on the plant enzyme used and protein characteristics. Sous vide processing improves the rate and extent of protein digestibility, but the protein digestion rate decreases with increasing temperature and heating time. Ultrasound, high pressure, or pulsed electric field treatments degrade the protein structure and increase the proteolytic enzyme contact area to improve the protein digestion rate.

• Food Science and Preservation
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• v.16 no.6
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• pp.1008-1012
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• 2009

We investigated the biological activities of ethanol extracts obtained from five endive cultivars. Free radical-scavenging activities of extracts from Redoria, Halifax, Vintor, Kibora, and Metafora cultivars were 94.2%, 60.8%, 66.6%, 70.0% and 67.4%, respectively. The extract from Redoria showed the highest activity among all the tested samples including BHT (Butylated hydroxyanisole) and vitamine C, known as antioxidant. Endive extracts slightly (17.5 - 38.6%) inhibited $\alpha$-glucosidase activity. However, there is no inhibitory activity against $\alpha$-amylase. In terms of proteolytic activity, all endive extracts showed strong activity than pancreatin (used as a positive control), and the extract of Redoria also exhibited stronger activity than other extracts as well as free radical scavenging activity. These results indicate that endive, especially the Redoria cultivar, can be used as a natural resource for development of antioxidants or materials aiding digestion.

• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.375-380
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• 1996

The gene coding for glutaryl-7-aminocephalosporanic acid (GL-7-ACA) acylase was cloned from Pseudomonas sp. GK16 and some of its characteristics were analyzed. The complete nucleotide sequence revealed that the putative open reading frame is 2160 bases long and encodes 720 amino acids. By SDS-PAGE three proteins, approximately corresponding to 70, 54 and 16 kDa of molecular weight, were detected in E. coli cells carrying pGAP18. The largest protein should be a precursor which is not processed yet, while the other two proteins must be derived from the precursor by the proteolytic processing.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.839-846
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• 1994

Changing concepts in fishery science increasingly are recognizing depletion of traditional stocks, utilization of alternate(non-traditional) species, demand for high quality products, and a total resource utilization approach. Innovative practices are occurring in fisheries processing wherein solid and liquid discharges are no longer treated as 'waste,' but rather as valuable feedstocks for recovery of a variety of value-added ('value enhanced') by-products. Among these are protein hydrolysates, soluble proteins and amino acids, proteolytic enzymes, flavor and flavor extracts, pigments, and biopolymers such as chitosan. Properties and applications of this deacetylated derivative of chitin are noted. Crustacean processing by-products are discussed in terms of their serving as materials for generation of natural flavors and flavor extracts, and products such as fish sauces using contemporary enzymatic techniques. Various food and feed applications of fisheries processing by-products are illustrated with increased usage seen in formulated diets for an expanding aquaculture market. Examples are given of aquaculture becoming increasingly significant in global fisheries resource projections. Critical issues in the international seafood industry Include those of seafood quality, processing quality assurance (HACCP), and recognition of the nutritional and health-related properties of fisheries products. A variety of current seafood processing research is discussed, including that of alternate fish species for surimi manufacture and formulation of value-added seafood products from crawfish and blue crab processing operations. Increasing emphasis is being placed on international aspects of global fisheries and the role of aquaculture in such considerations. Coupled with the need for the aquatic food industry to develop innovative seafood products for the 21st century is that of total resource utilization. Contemporary approaches in seafood processing recognize the need to discard the traditional concept of processing 'waste' and adapt a more realistic, and economically sound, approach of usable by-products for food and feed application. For example, in a period of declining natural fishery resources it is no longer feasible to discard fish frames following fillet removal when a significant amount of residual valuable flesh is present that can be readily recovered and properly utilized in a variety of mince-based formulated seafood products.

• Food Science of Animal Resources
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• v.40 no.3
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• pp.415-425
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• 2020

It is believed that two main proteolytic systems are involved in the tenderization of meat: the cathepsins and the calpains. Many researchers consider the calpain system to be the major contributor to meat tenderness during post-mortem storage. However, the role and activity of cathepsins during post-mortem storage or low temperature meat processing is unclear, particularly for the tough meat cuts like brisket. Thus, the study was designed to investigate the effects of cold (refrigerated and frozen) storage and sous vide processing on the activities of cathepsin B, H, and L in beef brisket. There were no significant changes in pH and cathepsin H activity throughout the 18 d of storage at both temperatures. However, an increase in cathepsin B activity was observed during the first 4 d at both storage temperatures, but subsequently the activity remained unchanged. Cathepsins B and L were found to be more heat stable at sous vide temperatures (50℃ for 24 h, 55℃ for 5 h and at 60℃ and 70℃ for 1 h) compared to cathepsin H. Cathepsin B+L activity was found to increase after sous vide cooking at 50℃ for 1 h but decreased to about 47% relative to the uncooked control after 24 h of cooking. These results suggest that cathepsins B and L may contribute to the improved meat tenderness usually seen in sous vide cooked brisket meat.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.231-243
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• 1998

In the present study, we provide evidence that ginsenoside $Rh_2$ (G-$Rh_2$) as well as staurosporine induces apoptosis of human hepatoma SK-HEP-1 cells by caspase 3-mediated processing of $p21^{WAFI/CIPI}$ in the early stage of apoptosls. Immunoblottings showed that G-$Rh_2$ as well as statrosporine induced the processing of caspase-3 to an active form, pl7. In stable Bcl-2 transfectants however, G-$Rh_2$ induced DNA fragmentation, while staurosporine did not. In the early stage of apoptosis, $p21^{WAFI/CIPI}$ was detected to undergo proteolytic processing specifically conducted by caspase-3. $p21^{WAFI/CIPI}$ translated in vitro was cleaved into a p14 fragment, when incubated with cell extracts obtained from either G-$Rh_2$- or staurosporine-treated cells. Cleavage was equally inhibited in both cases by adding Ac-DEVD-cho, a specific caspase-3 inhibitor, but not by Ac-YVkD-cho, a specific caspase-l inhibitor. Similarly, $p21^{WAFI/CIPI}$ was efficiently leaved by recombinant caspase-3 overexpressed in E. coli. Moreover, the endogenous $p21^{WAFI/CIPI}$ of untreated-cell extracts was also cleaved by recombinant caspase-3. Mutation analysis allowed identification of two caspase-3 cleavage sites, $DHVD^{112}$/L and $SMTD^{149}$/F, which are located within, or near the interaction domains for cyclins, Cdks, and PCNA. Taken together, these results show that G-$Rh_2$ as well as staurosporine increases caspase-3 activity, which in turn directly cleaves $p21^{WAFI/CIPI}$ resulting in elevation of Cdk kinase activity in the early stages of apoptosis. We propose that proteolytic cleavage of $p21^{WAFI/CIPI}$ is a functionally relevant event that allows unleashing the cyclin/Cdk activity from the inhibitor seen in the earlier stage of apoptosis, the event of which may be associated with the triggering mechanism for the execution of apoptosis.

• BMB Reports
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• v.43 no.6
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• pp.427-431
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• 2010

Cyt2Aa2 is a mosquito-larvicidal protein produced as a 29 kDa crystalline protoxin from Bacillus thuringiensis subsp. darmstadiensis. To become an active toxin, proteolytic processing is required to remove amino acids from its N- and C-termini. This study aims to investigate the functional role of amino acid residues on the N-terminal ${\beta}1$ and C-terminal ${\alpha}F$ of Cyt2Aa2 protoxin. Mutant protoxins were constructed, characterized and compared to the wild type Cyt2Aa2. Protein expression data and SDS-PAGE analysis revealed that substitution at leucine-33 (L33) of ${\beta}1$ has a critical effect on dimer formation and structural stability against proteases. In addition, amino acids N230 and I233-F237 around the C-terminus ${\alpha}F$ demonstrated a crucial role in protecting the protoxin from proteolytic digestion. These results suggested that ${\beta}1$ and ${\alpha}F$ on the Nand C-terminal ends of Cyt2Aa2 protoxin play an important role in the molecular interaction and in maintaining the structural stability of the protoxin.