• Food Science of Animal Resources
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• v.28 no.5
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• pp.675-680
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• 2008

The physical quality and microbial safety of Korean beef jerky was evaluated at various steps during its preparation. Microbial counts in raw beef demonstrated mesophillic bacteria at 4.20 Log CFU/g, psychrotrophic bacteria at 3.85 Log CFU/g, anaerobic bacteria at 4.90 Log CFU/g, and yeast and molds at 1.92 Log CFU/g. Spore-forming bacteria and coliforms were not detected in raw beef samples. Spices and spiced meats showed similar trends in microbial counts, demonstrating minimal microbial contamination during these stages of preparation. The final beef jerky product exhibited counts of mesophillic bacteria at 1.15-1.66 Log CFU/g, psychrotrophic bacteria at 1.15-1.66 Log CFU/g, and anaerobic bacteria at 0.81-1.72 Log CFU/g. Spore-forming bacteria, yeast and molds, and coliforms were not detected in beef jerky. Significant differences from added ingredients occurred for instron textural profile analysis traits for hardness. In general, Korean beef jerky with humectant and tenderizer had lower hardness than control (without humectant and tenderizer). Also, the sample added with 0.01% protease from Streptomyces griseus had lower hardness than all samples. All samples had 0.7l to 0.72 water activities, and the color and pH were not shown in significant changes of all samples.

• YAKHAK HOEJI
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• v.37 no.2
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• pp.129-135
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• 1993

Serratia sp. Y-4 was isolated from soil. Many characteristics of the strain and optimum cultivation condition for protease production were investigated.,The protease from Serratia sp. Y-4 was purified and studied for the properties of the enzyme. The isolated strain was identified to the genus Serratia. The strain was cultivated in 1%-casein, 0.5%-Na$_{3}$PO$_{4}$.7H$_{2}$O, 0.1%-NaCl, 0.05%-KCI, 0.02%-MgSO$_{4}$.7H$_{2}$O, 0.02%-CaCl$_{2}$.2H$_{2}$O, 0.02%-ZnSO$_{4}$.7H$_{2}$O, 0.02%-MnCl$_{2}$.4H$_{2}$O and 0.5%-soy bean oil at pH 7.0 for 35 hrs. The enzyme was purified about 5.89 fold from the culture broth with 31.1% recovery and 19,613 u/mg through ultrafiltration, ammonium sulfate, DEAE-sephacel and Superose-12 chromatography. The purified enzyme was identified as one band by isoelectric focusing, SDS- and native-PAGE. It has maxium activity at $37^{\circ}C$ and pH 9.0. Molecular weight of it is approx. 50 kD and pl is about 6.70. Its Km value for casein was 20 mg/ml. 5 mM-EDTA, 5mM-SDS, Ag$^{+1}$, Cu$^{+2}$, Hg$^{+2}$ and Pb$^{+2}$ inhibited the enzyme.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.4
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• pp.363-369
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• 2004

Three different doengjang(fermented soybean paste) were prepared by using B. subtilis SS103 with high angiotensin converting enzyme(ACE) inhibitory activity, Asp. oryzae and mixed culture of two organisms, respectively. Quality characteristics and the inhibitory activity were compared. $\beta$-Amylase activity rapidly increased during 30 days of fermentation, but lower activity was found in doenjang prepared with B. subtilis. However, $\alpha$-Galactosidase activity decreased for 15 days of fermentation and little activity was observed after that fermentation period. Protease production tended to increase during the fermentation. High protease activity was found only in doengjang prepared with Asp. oryzae, but the doengjang prepared with B. subtilis SS103 showed very low activity. Total isoflavone content at 90 day fermentation was the highest in doengjang prepared with mixture of Asp. oryzae and B. subtilis. ACE inhibitory activity increased during the fermentation period. The highest activity was found in doengjang made with mixture of Asp. oryzae and B. subtilis. Sensory evaluation on doengjang itself and its soup indicated that doengjang made with mixture of Asp. oryzae and B. subtilis showed higher acceptability on taste, flavor and color than those prepared with only Asp. oryzae or B. subtilis, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1068-1076
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• 1997

This study was carried out to elucidate the utility of fusant for shortening the ripening time of imitation processed cheese. L. bulgaricus exhibited the highest protease and lactase activity and L. helveticus revealed the highest lipase activity. Fusant was shown to be high in the activity of protease and lactase. The total volatile free fatty acid produced by the cheese treated with L. helveticus was markedly increased after four ripening days and was gently increased after nine ripening days. However, L. bulgaricus significantly increased the total volatile free fatty acid between four and nine ripening days. In the case of fusant, the amount of total volatile free fatty acid was observed to increase at a constant rate relative to the ripening time. In free fatty acid production at different ripening times, L. bulfaricus generated caproic acid and caprilic acid abundantly while it produced a poor quantity of capric acid, lauric acid, and myristic acid. In the cheese sample treated with L. helveticus, the amount of caproic acid and capylic acid was on increase as the ripening time increased. The amount of caproic acid and caprylic acid produced by fusant was less than that produced by the other two starters. In the panel sensory evaluation, the flavor intensity and preference increased as the ripening time increased. The cheese sample treated with fusant showed the highest flavor intensity at 7 days, whereas cheese treated with L. helveticus exhibited the highest flavor intensity at 15 or 30 days. The cheese treated with L. helveticus showed the highest preference at 7 days, but cheese treated with fusant exhibited the highest preference at 30 days.

• Journal of Applied Biological Chemistry
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• v.63 no.4
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• pp.291-295
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• 2020

In order to increase the utilization of defatted sesame meal (DSM), a by-product of sesame oil production, the conditions of extraction of insoluble proteins from DSM by enzyme treatment were investigated. As a result of comparing the treatment results of proteolytic enzymes Alcalase, Flavorzyme, Neutrase, and Protamex with control, Protamex was effective in increasing the total solid and protein content. At the reaction conditions of Protamex (50 ℃, pH 6.0), the dosage of enzymes was appropriate for 1% of DSM and 3 h of enzyme reaction time. To improve the efficiency of enzymatic treatment, the protein content extracted increased as the heat treatment temperature increased, and slightly increased above 110 ℃. As a result of investigating the effect of the combination treatment of cell lytic enzyme (Tunicase) and protease (Protamex) on protein solubilization, it was most effective to treat the cell lytic enzyme after processing the protease. After heat treatment (110 ℃, 10 min), sequential treatment of Protamex and Tunicase increased the protein content by about 3.5 times (9.85→35.58 mg/mL) of the non-heated control and 2.2 times (15.83→35.58 mg/mL) of the heat treated control.

• Animal Bioscience
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• v.37 no.7
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• pp.1255-1262
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• 2024

Objective: The present study evaluated the effect of flaxseed meal degraded by a protease, Lactobacillus plantarum, or both on the growth performance, nutrient digestibility, and health status of broilers. Methods: There were four diets containing flaxseed meals in its non-degraded form (control, CON), degraded with 3,000 U/kg of protease (enzymatic, ELM), 1.0×10⁹ CFU/kg of Lactobacillus plantarum (fermented, FLM), or both (dual-degraded, DLM). Each form of flaxseed meals was added at 15% of diet. A total of 480 yellow-feathered broilers at 22 d of age were distributed into 4 groups with 6 replicates of 20 chickens each. The feeding trial lasted for 42 d. Growth performance, apparent fecal digestibility (dry matter, energy, crude protein, and ash), and serum immunoglobins and antioxidases were determined at 42 and 63 d of age. Results: Results showed that ELM, FLM, and DLM increased (p<0.001) the contents of peptides and decreased (p<0.001) cyanogenic glycosides, compared to CON. The diets with degraded flaxseed meals increased (p<0.05) feed intake and body weight gain throughout the feeding trial, and the digestibility of energy, crude protein, and ash at the end of feeding trial. Furthermore, all degraded groups enhanced (p<0.05) broiler health status by increasing serum immunoglobulins A and G. Additinally, DLM showed more pronounced effects (p<0.05) on these parameters than ELM or FLM. Conclusion: Flaxseed meals degraded by enzymolysis, fermentation, or both had improved nutrition and application in broilers.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.162-165
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• 2003

In order to study the secretion of the human urokinase-type plasminogen activator, u-PA, from the yeast yarrowia lipolytica, three kinds of integrative expression vector were constructed. These vectors differed only in their secretion control legions, pre-, pre-dip-(dipeptide Stretch) or pre-dip-pro sequences of the alkaline extracellular protease, which were joined inflame to the human u-PA cDNA. The recombinant Y. lipolytica Strains, transformed with the expression vectors, secreted the hyperglycosylated u-PA. A fibrin plate assay of the culture supernatants showed that the hyperglycosylated u-PA proteins could catalyze fibrinolysis, and that the pre-dip sequence was the most efficient secretory signal for the secretion of the u-PA from Y. lipolyica. This result suggests that Y. lipolytica can be developed as a potential host for the production of recombinant human u-PA.

• Journal of Animal Science and Technology
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• v.57 no.7
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• pp.23.1-23.6
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• 2015

Cellulose degrading bacteria from koala faeces were isolated using caboxymethylcellulose-Congo red agar, screened in vitro for different hydrolytic enzyme activities and phylogenetically characterized using molecular tools. Bacillus sp. and Pseudomonas sp. were the most prominent bacteria from koala faeces. The isolates demonstrated good xylanase, amylase, lipase, protease, tannase and lignin peroxidase activities apart from endoglucanase activity. Furthermore many isolates grew in the presence of phenanthrene, indicating their probable application for bioremediation. Potential isolates can be exploited further for industrial enzyme production or in bioremediation of contaminated sites.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.299-302
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• 2000

Actinoplanes teichomyceticus ATCC 31121 was mutated with UV to obtain a superior mutant strain with increasing level of teicoplanin production. In this investigation lethal curve was obtained and the optimal condition to induce mutagenesis was determined and to isolate the desirable mutant strain. It was also confirmed that teicoplanin activities by agar diffusion method to be compared to the mother strain. One mutant strain, T991014-1 that had the highest teicoplanin productivity was finally selected for further investigation including fermentation pattern. The mutant was characterized by the various tests such as amylase activity, protease activity, antibiotic resistance, autotoxicity, and productivity.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.554-557
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• 2000

Strain JV3 was isolated from commercial Swiss cheese products and identified as a bacteriocin producer, which has bactericidal activity against Leuconostoc mesenteroides KCCM 11324. Strain JW3 was identified tentatively as Lactococcus lactis by the API test. The activity of lacticin JW3, named tentatively as the bacteriocin produced by Lactococcus lactis JW3, was detected during the mid-log growth phase, and reached a maximum during the early stationary phase, and decreased after the late stationary phase. Its antimicrobial activity on sensitive indicator cells was completely disappeared by protease IV. The inhibitory activities of lacticin JW3 were detected during treatments of up to $121\'^{circ}C$ for 15 min. Lacticin JW3 was very stable over a pH range of 2.0 to 9.0 The apparent molecular mass of lacticin JW3 was estimated to be in the region of 3-3.5kDa, which was determined by the direct detection of bactericidal activity after SDS-PAGE.