• Archives of Pharmacal Research
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• v.16 no.1
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• pp.1-5
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• 1993

The reaction of sulfhydryl groups in human serum ablumin with bacteriostatic and hypotensive notrosating agents such as sodium nitorprusside and sodium nitrite has been examined. The low reactivity of sodium nitroprusside to sulfhydral groups in albumin has been observed and the sterical inaccessilibility of the agent site which sulfhydryl group resides was implicated. The reaction of sodium nitrite with albumin was highly influenced by pH and little reactivity was observed at physiological pH. On the other hand, the reaction between albumin and S-nitrosoglutatione, an intermediate induced from the reaction of glutathione and nitrosating agents, resulted in the rapid decrease of free sulfhydryl groups in albumin. S-Nitrosylation of the sulfhydryl group by S-nitrosoglutathione and the subsequent production of mixed disulfide is the probable route of modification. In the physiological system, S-nitroso-glutathione may act as an active intermediate in expressing reacivity of nitrosating agents to sulfhydryl groups in albumin.

• Journal of fish pathology
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• v.5 no.1
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• pp.9-18
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• 1992

In order to know the defense mechanism of fish, bactericidal activity was examined into the sera of carp Cyprinus carpio, tilapia Oreochromis niloticus and flounder Paralichthys olivaseus. Each examined normal serum of fishes showed the bactericidal activity against avirulent Escherichia coli but it wasn't appeared against virulent Edwardsiella tarda. When the normal serum of each fish was treated with zymosan, it lost the bactericidal activity completely. After addition of EGTA into the normal serum of each fish, the sera of tilapia and flounder still exhibited the bactericidal activity but the serum of carp lost it. In the presence of specific antibody and complement, bactericidal activity of each antiserum was exhibited high level with in one hour incubation. On the other hand, heat inactivated antiserum showed bacteriostatic reaction. From the above results, although the activity of alternative or classical pathway of each fish complement is different, it is an important function in fish defense mechanism.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.581-585
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• 1996

A new formal total synthesis of (+)-6-oxo-3, 4, 4a, 5-tetrahydro-3-hydroxy-2, 2-dimenthylnaphtho-1, 2-pyran (1) which has been known to have bactericidal, bacteriostatic, fungicidal, fungistatic activities against Staphylococcus aureus and other microorganism, is described. The key reaction involves enantioselective prenylation of .alpha.-tetralone via chiral lithioenamine.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.20-26
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• 1986

Very little information is available in the literature on storage of fish sauce. Therefore, microbiological and chemical chracteristics during storage and quality of fish sauce were investigated and discussed to present data about the optimum storage condition. The chopped sardine meat was mixed with equal amount of water and $9\%$(w/w) of $75\%$ vital wheat gluten and then hydrolyzed by addition of commercial proteolytic enzymes such as bromelain, papaya protease, ficin and a enzyme mixture (Pacific Chem. Co.) for 4 hours at $52.5^{\circ}C$. The reaction mixture was heated for 30 min at $100^{\circ}C$ for enzyme inactivation, pasteurization and color development and then centrifuged for 20 min at 4,000 rpm. Table salt and benzoic acid were added for bacteriostatic effect and stored for 80 days at $15{\pm}1^{\circ}C$ and $30{\pm}1^{\circ}C$. The results were summarized as follows: 1. The amount of amino-nitrogen and pH of fish sauce were almost unchanged during storage. 2. Mininum concentration of salt for bacteriostatic activity was $9\%$(w/w) regardless of addition of benzoic acid. 3. the yields of amino-nitrogen were $63.1\%$ for the hydrolysate prepared without enzyme, $79.7\%$ for that with bromelain, $69.9\%$ with ficin, $74.3\%$ with papaya pretense, and $78.1\%$ with enzyme mixture, respectively. 4. The contents of amino-nitrogen were $4510.0mg\%$ on the dry basis for the product prepared by autolysis, $5483.2mg\%$ for that prepared with bromelain, $5305.7mg\%$ with ficin, $4994.1mg\%$ with papaya protease and $5582.3mg\%$ with the enzyme mixture, respectively. 5. The contents of crude protein were $51.35\%$ on the dry basis for the product prepared by autolysis and 55 to $59\%$ for prepared with commercial enzymes. 6. The hydrolysate prepared with the enzyme mixture revealed a little stronger meaty taste than any other products. 7. The level of crude protein in residues was still high ($69.5{\sim}77.2\%$ on the dry basis) and might be originated from the added vital wheat gluten.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.10-19
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• 1986

A study on the rapid fermentation of fish sauce has been carried out for effective utilization of sardine. The frozen sardine was thawed at room temperature, chopped, homogenized with equal amount of water and then hydrolyzed by addition of commercial proteolytic enzymes such as bromelain, papaya protease, ficin and a enzyme mixture under different conditions of hydrolysis. The effect of wheat gluten for masking fishy odor and color development during thermal treatment were also tested. The reaction mixture was heated for 30 minutes at $100^{\circ}C$ for enzyme inactivation, pasteurization and color development and then centrifuged for 20 minutes at 4,000 rpm. Finally, table salt and benzoic acid were added for bacteriostatic effect. The results were summarized as follows ; 1. The hydrolyzing temperature, time, pH and the concentration of enzymes based on the weight of whole sardine for optimal hydrolysis were as follows: autolysis, $52.5^{\circ}C$, 4 hours, pH 8.0: with $0.25\%$ bromelain, $52.5^{\circ}C$, 4 hours, pH 6.6 :with $0.25\%$ ficin, $52.5^{\circ}C$, 4 hours, pH 6.8: with $0.3\%$ papaya protease, $52.5^{\circ}C$, 4 hours, pH 6.6: with $6\%$ enzyme mixture, $52.5^{\circ}C$, 4 hours, pH 6.9, respectively. But pH control was not much beneficial in increasing yield. 2. The hydrolytic reaction of chopped sardine with proteolytic enzymes could be interpreted as a first order reaction that devided into 2 periods with different reaction rate constsnts. $Q_{10}$ values of the first period prior to 4 hours were 1.23 to 1.31, and those of post 4 hours were 1.25 to 1.55. The corresponding activation energies were $1.81{\times}10^4\;to\;2.34{\times}10^4\;kJ/kmol$ and $1.92{\times}10^4\;to\;3.77{\times}10^4\;kJ/kmol$, respectively. 3. The reasonable amount of $75\%$ vital wheat gluten for addition was $9\%$ of chopped sardine. 4. The dark brown color was mainly developed during the thermal treatment for 30 minutes at $100^{\circ}C$ and not changed during storage.

• KSBB Journal
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• v.14 no.4
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• pp.460-464
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• 1999

Methicillin-resistant Staphyloccus aureus (MRSA) has been known to be resistant to many kinds of antibiotics and causes a problem of nosnocomial infection since the third generation of cephalosporines has been introduced in the 1980s. As antibiotic sensitivity tests which have been routinely used to detect MRSA in the laboratory depend on the culture conditions such as, pH, temperature, and time, etc., it is difficult to decide in the case of borderline- or low-level of MRSA. Therefore it would be necessary to develope a new method based on the molecular biological technique to overcome these problems. In this study, we extracted DNA from S. aureus and performed polymerase chain reaction (PCR) to amplify mec A gene, encoding penicillin-binding protein 2' (PBP-2'), which is known to confer bacteria resistance to the bacteriostatic action of methicillin. The results were compares with those of minimal inhibitory concentration (MIC) test. When MIC test with oxacillin was performed on the 120 isolates of S. aureus from each patient's specimens, 64 of them were MRSA and 56 of them were methicillin-sensitive Staphylococcus aureus (MSSA). In pus specimen, more precisely, 61.9% (26/42) of MRSA was detected, and 44.2% (19/43), 60% (9/15) and 50% (10/20) of MRSA were detected in sputum, body fluid, and other specimen respectively. When 40 isolates of MRSA and MSSA were tested by PCR method and compares with the results of MIC method, different results were obtained from 1 isolate of MRSA (2.5%) and in 2 isolates of MSSA (5%) suggesting that PCR method should be performed at the same time for more accurate clinical test of MRSA.

• Journal of fish pathology
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• v.10 no.1
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• pp.1-14
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• 1997

Major object of this study was to investigate the causative organism of th e diseased cultured fingerling of sea bass, L japonicus. The experimental results are summarized as follows ; Staphylococcus epidermidis, isolated from the liver, kidney, spleen and brain, was considered to be the causative organism. External symptoms of this disease were congestion and hemorrhages in eyes. Anatomical symptoms were hemorrhage of brain, congestion of liver, and slight swelling of kidney and spleen. Growth of the isolates was good on BHIA, HIA and Staphylococcus No. 110. The growth occurred at a range(optimum) of $10\sim45^{\circ}C(35\sim40^{\circ}C)$, 0~9% (1~3%) of NaCl concentration and pH 4~10(8). DNase and coagulase production of all isolated strains were nagative, but was positive in hemolysis. Urease was positive reaction, and novobiocin resistance was nagative. Acid was produced anaerobically from glucose and maltose. Acid was produced aerobically from glucose, galactose, sucrose, maltose and dextrine. But gas was not produced from any carbohydrates. When the isolated strain was injected intramuscularly on fingerling of sea bass, L japonicus, it had virulence at $1.7{\times}10^{10}$ viable cells/$m\ell$ for all fish examined but no virulence at $1.7{\times}10^4$ viable cells/$m\ell$. Bacitracin, Erythromycin and Nofloxacin were observed as bacteriostatic agents to the strain, but Colistin, Gentamicin and Nalidixic acid were not. There were remarkable congestion of the brain, regressive necrosis of the liver, and showed necrosis of the epithelial cells of renal tubules in kidney tissues.