Comparative insecticidal efficiency between compounded pyrethroids and its preparations cooperated with several synergists was studied. As main components, Group A contained Permethrine Phthalthrine, Group B contained Permethrine Furameth rine and Group C contained Phthalthrine Dichlorvos. As synergists Piperonyl Butoxide (P.B.O.), N-Octylbicycloheptene dicarboximide (MGK-264), Octachlorodipropylether (S-421) was cooperated in each group. These preparations was treated to either Blattella G. or Musca D. for comparing about insecticidal efficiency[Knock-down rate (KT_(50), KT_(90)) and cumulative mortaility(percent/hrs)]. When the synergists was added to each Group, the insecticidal efficiency was improved. The most potent synergists was P.B.O. and the potency was decreased in the rank order of S-421$gt;MGK-264. The more the concentration of synergists was increased, the more the insecticidal effciency was improved. The rank order was 1:5≥1:4$gt; 1:3 in all three groups. The mortality (percent) according to time was similar to either KT_(50), or KT_(90-). Knock-down rate was appropriate parameter for the indicator about potency.
The relationship between storage stability and calcium contents extracted from anchovy according to particle sizes was investigated in this paper. The results are as follows; 1. The acid value (AV) and the peroxide value (POV) of anchovy were in the rank order of whole anchovy$lt;35$lt;50$lt;80 mesh by particle sizes and 6$lt;12$lt;18$lt;30 months by storage term. 2. The Calcium (Ca) and Phosphorus (P) contents extracted from anchovy were in the rank order of whole anchovy$lt;35$lt;50$lt;80 mesh by particle sizes and 10$lt;20$lt;30 minutes by heating time. The extracted amount of Ca was the largest when anchovy particles with 80 mesh were heated for 30 minutes. In that case the amount of Ca in the anchovy stocks was 52.54 mg. 3. The amount ratio between Ca and P was in the rank order of 30$lt;20$lt;10 minutes by boiling time and indicated 1:3.99-5.16 by each part. The lowest ratio of Ca to P was 1:3.99 when anchovy particles with 80 mesh were heated for 30 minutes. 196
In Korea, a small proportion of fishery products are contaminated with a considerable amount of potentially hazardous contaminants. So, there is generally a high risks to consumers. Inorganic contaminants with the greatest potential for toxicity are Sb, As, Cd, Pb, Hg, Se and the Sulfides. As appears to be much more variable than the others. This study was performed to assess the levels of the As in fisheries caught from the waters of the western coast of Korea. The samples included 26 kinds of fishes, 18 kinds of Mollusca, 3 kinds of Crustacea and 7 kinds of salted fishes. The Moisture content of molluscans was significantly higher than that of others (p$lt;0.05). And the As contents of crustaceans were significantly higher than those of fishes, molluscans and salted fishes (p$lt;0.05). The As content of Turban shell was 51.62 ppm, which was the highest among the samples. Also, the As contents of eel, cattle fish and blue crab were found to be higher than in other fisheries. This variability offers a solution for the reduction of eosure to As through restricting the harvest of aquatic organism from the western coast of Korea.
An improved antibody-coated sensor system based on quartz crystal microbalance was developed for the detection of Salmonella spp. An antibody against Salmonella common structural antigen was immobilized onto one gold electrode of the piezoelectric quartz crystal surface by various immobilization procedures. The best results in sensitivity and stability were obtained with the thin layers of protein A and 3,3'-dithiopropionimidate 2HCl (DTBP), a homobifunctional thiol-cleavable crosslinker. After the addition of a S. typhimurium suspension into a reaction cell with 0.1 M sodium phosphate buffer, pH 7.2, the resonant frequency owing to S. typhimurium adsorption decreased conspicuously. The antibody-immobilized crystals prepared by the gold-protein A complex formation and DTBP thiolation showed the frequency shifts of 80 and 283 Hz, respectively. The time required for maximum frequency shift was about 30-60 min. The antibody-coated crystal could be reused for 6-8 consecutive assays.
Bioconcentration factors of some carbamates BPMC, carbaryl and carbofuran were determined. The tested fishes were zebrafish (Brachydanio rerio) and red sword tail (Xiphophorus hellieri). The fishes were exposed to 0.05 ppm, 0.01 ppm, 0.50 ppm, one- hundredth concentration of 96-hrs LC_(50) and one-thousandth concentration of 96-hrs LC_(50) and test periods were 3, 5 and 8 days. Obtained results are summerized as follows: In the case of BPMC and carbaryl, BPMC and carbaryl concentration in zebrafish extract and BCFs of BPMC, carbaryl were lower than those of red sword tail, and increased as increasing test concentration. In the case of same experimental concentrations, BPMC concentration in zebrafish extract and BCFs of BPMC were decreased as prolonging test periods. In the case of same experimental periods, carbaryl concentration in zebrafish extract and BCFs of carbaryl were decreased as increasing test concentration, especially dropped at 0.50 ppm. Carbofuran did not bioaccumulate in zebrafish for test periods, in the case of red sword tail, it was impossible to calculate on BCFs data because test concentration of one-hundredth and one-thousandth of 96hrs LC_(50) was under the detecting limit on GC. Test concentration of 0.05 and 0.10 ppm were the same tendency with BPMC and carbaryl. Determined depuration rate conatant were highest on carbofuran, and followed by carbaryl, and BPMC. It is suggested that low BCF of carbofuran is due to its relatively high water solubility and depuration rate, compared to BPMC and carbaryl. Therefore, carbofuran had no little bioconcentration effect on the aquatic ecosystem.
The purpose of this study is to examine the phototoxicity of four phenothiazine derivatives such as chlorpromazine, perphenazine, trifluoroperazine and promethazine, and to investigate the effects of ascorbic acid on their phototoxicity by LTVB irradiation. Effects of the test compounds on RBCs were monitored with a spectrophotometer by the method of Kahn et al. The extent of photohemolysis by tested phenothiazine derivatives were increased with their concentration and toxic photoproducts were formed by chlorpromazine and promethazine with preirradiated UVB. Photohemolysis postirradiated chlorpromazine and perphenazine and preirradiated promethazine were decreased with the use of ascorbic acid significantly.
Chicken carcass microflora were evaluated for aerobic microorganisms after defeathering, evisceration, washing, chilling, and sanitizing during a commercial chicken processing and storage at wholesale and retailsale levels. Sampling was at between December 1997, and March, 1998. Tap water washing and sanitizing with 25 ppm chlorine for 10 sec significantly (P$lt;0.05) reduced aerobic plate counts (APC) and gram-negative bacterial counts (GNC) on chicken carcasses from a commercial chicken-processing plant. After 4 days at 2±2℃, APC and GNC on chicken carcasses in retailsale store rapidly increased compared to those in wholesale store (P$lt;0.05). Chicken wings from retailsale store significantly (P$lt;0.05) decreased generation time (GT) compared to other chicken carcasses.
Panax ginseng C.A. Meyer has been extensively used in the traditional oriental medicine as a restorative, tonic and prophylatic agent. Petroleum ether extract of panax ginseng C.A. Meyer (GPE) and its several fractions (P1-P5) were tested for the evaluation of antigenotoxicity against N-methyl-N-nitrosourea (MNU) and benzo(a)pyrene [B(a)P]-induced micronucleated reticulocytes in mouse peripheral blood. GPE and P2 showed more significant anticlastogenicity than other fractions did. To elucidate the anticlastogenic action mechanism of GPE and P2 against B(a)P, the alteration of B(a)P metabolism was studied. GPE and P2 inhibited B(a)P metabolism in the presence of S-9 mix and decreased B(a)P-DNA binding in calf thymus DNA with S-9 mix. They also decreased [3H] MNU induced DNA binding and methylation to 7-methyl guanine and O^5-methyl guanine adducts in calf thymus DNA by HPLC analysis. These results suggest that the anticlastogenicity of GPE and P2 on the B(a)P or MNU-induced clastogenicity is due to decrease of DNA binding with B(a)P or MNU, the inhibition of metabolism with B(a)P and the inhibition of methylation in DNA. Therefore, GPE and P2 may be useful chemopreventive agents of alkylating agent like MNU and secondary carcinogen like B(a)P.
Bamboo salt has been used as a traditional remedy for gastric ulcer and gastro-intestinal disorders. It is produced by baking the salt packed in bamboo cylinder nine times under the fire of pine tree. Three of commercially available bamboo salt products (bamboo salt A, B, and C) were characterized by qualitative and quantitative analyses using inductively coupled plasma (ICP) spectrometer, ion chromatograph (IC), X-ray diffractometer (XRD), and electron microscope (EM). Compared with crude salt, the contents of iron, silicon, potassium, and phosphate in the bamboo salt products were higher whereas the sulfate content was lower. Water-insoluble fraction of bamboo salts contained the following compounds; MgO, SiO₂, Mg₂SiO₄, and CaMgSiO₄. The study on the microscopic structures of the bamboo salts were shown to have smooth surface and fused shape compared with crude salt. Among the three bamboo salt products, product A was used to test a possible inhibitory effect on gastric acid secretion. Each test material (bamboo salt A, crude salt, and reagent-grade NaCl) was given orally to Sprague-Dawley rats at doses of 0.2, 1.0, and 2.0 g/kg for 28 days before pyrolus ligation. Twenty four hours after the last administration of the test materials, volume, pH, total acidity, and pepsin activity of gastric juice were measured by the Shay-ligation method. No significant differences were observed in the secretion of gastric acid between treated groups (bamboo salt-, crude salt- and reagent-grade NaCl-treated groups) and control group (distilled water-treated group). This result demonstrated that bamboo salt did not exert anti-ulcer activities in experimental animals used in the present study.
The acetaminophen (APAP), an antipyretic and analgesic agent, induces the hepatotoxicity by increasing influx of calcium and destabilizing the cellular membrane which can be caused by N-acetyl p-benzoquinoneimine generated by cytochrome P-450 (CYP-450) when it is overdosed. Diltiazem (DIL), a calcium channel blocking agent, has been known to suppress the CYP-450 activities. To study the effect of DIL in APAP treated rats, the serum biotransformational enzyme analyses and the liver histopathologic examination were conducted on the rats which had been administered DIL at 3, 6, 9 and 12 hours after the 3,000 mg/kg of APAP administration. Following a single dose of DIL administered 12 hours after APAP administration, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, malondialdehyde and calcium contents of liver and microsome were significantly reduced. Glutathione S-transferase (GST) activity was significantly increased. Histopathologic studies showed that DIL had prevented the development of centrilobular necrosis induced by APAP in liver tissue. Our results suggested that diltiazem could inhibit the formation of free radical and the influx of calcium and could increase GST activity. Therefore, diltiazem can be administered at the time of 12 hours after overdosed APAP to diminish the liver damage.
The present study has been undertaken to investigate the effects of ginseng extract on the activities of several enzymes in serum of rats fed lard and alcohol. Thirty-five males of Sprague-Dawley strains weighed about 130 g were divided into 7 groups, each group receiving a different diet for 10 weeks; i.e. basal diet plus 15% lard, basal diet plus 5% alcohol, basal diet plus 5% ginseng extract, basal diet plus 15% lard and 5% ginseng extract. Determinations were carried out on the net weight gain, food efficiency ratio, weight of organs, and AST, ALT, lactate dehydrogenase, alkaline phosphatase activities in serum of rats. The results obtained were as follows: Rats given feed containing lard and alcohol showed significant decrease in net weight gain, but ginseng extract caused an increase in food efficiency ratio. Lard supplementation caused an increase in the weight of liver, kidney, spleen, but another groups did not. AST, ALT, ALP, LDH of serum were significantly increased in lard and alcohol containing group but ginseng extract feeding decreased enzyme activities compared to lard and alcohol containing group. The above results suggest that ginseng extract would prevent the metabolic disease of liver by preventing hyperlipemia caused by high fat diet.
The study was focused to investigate the effect of nitrosodimethylamine (NDMA) formation due to nitrosamine (NA) precursor and/or inhibitor addition to Kimchi during the fermentation of Kimchi at room temperature (16±2℃). The addition of nitrite and dimethylamine (DMA) to Kimchi showed the average 32-fold (21.3-113.9 ug/kg) and 9-fold (1.3-40.3 ug/kg) higher NDMA formation than control (0-5.6 ug/kg), respectively. Also, the addition of both nitrite and DMA resulted in the increase of NDMA formation to average 42-fold (39.4-155.7 ug/ kg) higher than control. On the other hand, the addition of 4 mM ascorbic acid to Kimchi with nitrite and DMA inhibited the formation of NDMA down to 71.3% of control. However, the addition of cysteine and erythorbic acid affected no inhibition to NDMA formation during the test. The addition of sodium sulfite increased NDMA formation. Accordingly, this showed that the amount of ascorbic acid generated during Kimchi fermentation played an important inhibition role for NA formation.
본 연구는 학교급식에서 Cook/chill system으로 생산 가능한 음식으로 삼치구이를 선정하고 모의실험을 통해 급식생산체계를 반복 실시함으로서 식품 위해 분석 중요관리점(HACCP)을 규명하고, 저장기간중의 음식품질 평가를 통해 합리적인 저장기한을 설정하고자 수행되었으며, 그 연구결과는 다음과 같다. 심치 구이의 온도소요시간 측정 결과, 온도상승이 일어난 검수 단계를 제외하면 각 생산단계별 온도-소요 시간 기준이 준수된 양호한 상태 하에 삼치구이가 생산되었음을 알 수 있었다. 삼치구이의 생산단계별 미생물 분석 결과 , 중온성 표준평판 균수의 경우 원재료 ($2.58{\pm}0.12\;Log\;CFU/g$)에서 냉장보관($2.70{\pm}0.42\;Log\;CFU/g$)까지의 품질은 우수하였다. 양념장으로 재우는 과정($3.82{\pm}0.52\;Log\;CFU/g$)에서 반복 실험중 일차에서만 대장균군, 분변성 대장균군이 각각 0.84 Log MPN/g으로 검출되었다. $160^{\circ}C$, 10분의 습열 조리와 $180^{\circ}C$, 3분의 건열 조리를 통해 삼치구이 내부온도는 $76^{\circ}C$로 측정되었는데, 조리 직후 심치구이에서는 중온균 ($1.83{\pm}0.49\;Log\;CFU/g$)만 검출되었고 저온균, 대장균군, 분변성 대장균군은 검출되지 않았다. 급성 냉장과 저장 5일을 거치는 동안 중온균은 거의 검출되지 않았으며 나머지 분석대상 미생물도 검출되지 않았다. 재가열과 배분단계에서도 분석대상 미생물이 전혀 검출되지 않았다. 삼치구이 전 생산단계에 걸쳐 Salmonella 와 Listeria monocytogenes는 검출되지 않았다. 5일의 저장동안 분석된 삼치구이의 pH, 산가, 휘발성 염기질소(TVBN) 함량과 관능 평가 결과, 삼치구이의 저장기한은 4일 이내로 제안되었다. 규명된 CCPs는 삼치의 구입과 검수, 가열 조리, 냉각, 냉장, 재가열 및 배식 단계였다.
The effect of gamma irradiation on the survival of spore bacteria was investigated in frozen cells (-18℃) with 0.1 M phosphate buffer and inoculated cells in beef. In the case of the frozen cells at log phase, the radiation D_(10) and 12D_(10) values were 0.29 kGy and 3.48 kGy in Bacillus subtilis, 0.39 kGy and 4.68 kGy in Bacillus cereus and 0.46 kGy and 5.52 kGy in Clostridium perfrigens. And inactivation factors were 6.52-10.34 and 10.87-17.24 at the dosage of 3 kGy and 5 kGy, respectively. The radiosensitivity of inoculated cells in beef showed the D_(10) value of 0.59-0.76 kGy, the 12D_(10) value of 7.08-9.12 kGy, and inactivation factors of 3.95-8.47. The radiosensitivity of the frozen cells was higher than that of inoculated cells in beef.
loom 1993 to 1996, 1,500 cases of foodborne disease was reported annually in Korea. Salmonellosis were 55.1% of the reported bacterial fordborne disease cases. However, in general, it is estimated that the reported incidence of salmonellosis represents less than the real incidence. This study showed that salmonellosis estimates 177,000 cases (about 150 times of reported cases) costing 5.9 billion won in Korea. Only medical costs and productivity losses were included in the estimate of costs of the 177,000 cases estimated to occur in 1996. This estimates were considerably difference to U.S.A. in cases and costs, but not significantly difference in cases/population (%), expense/GDP (%). Understanding the social economic costs of foodborne disease will be endorsed risk assessment as a necessary method for evaluation and improving food safety regulatory programs in Korea.
In order to investigate the species, serobiological characteristics and antibiotic sensitivity of Pseudomonas spp, we isolated Pseudomonas spp from 57 spring waters around Seoul area for spring, summer and autumn and identified Pseudomonas spp by biochemical characteristics and serological method. And also we tested the antibiotic sensitivity test by discdiffusion method. Of 57 spring waters tested, Pseudomonas spp were isolated from 33 spring waters(57.9%). Isolation rate of Pseudomonas spp in spring season was 28.1%, summer 21.1% and autumn 28.1%. Only 1 spring water was detected Pseudomonas spp in all seasons and 9 (15. 8%) were detected for 2 seasons and 13 (22.8%) were for only 1 season. Isolation rate of Pseudomonas spp at Mt. Cheonggye was 50% and followed by Mt. Bookhan 35.7%, Mt. Daemo 33.3%, Mt. Dobong 29.6%, Mt. Surak 25.9%, Mt. Woomyun 22.2% and Mt. Bulam 7.4%. Of 44 Pseudomonas spp, 22 strains (50%) were identified by Ps. putida, Ps. aeruginosa, Ps. tluorescens and Ps. mendocina were identified 6 strains (13.6%), respectively. 4 strains (9.1%) were identified by Ps. aureofaciens. Of 6 Ps. aieruginosa, serotype A was 2 strains, B, E, G, and K was 1 strain, respectively. Of 44 Pseudomonas spp, resistance rate to amoxicillin was 90.9% and followed by chloramphenicol 84.1%, tetracycline 84.1%, carbenicillin 81.8%, nalidixic acid 68.2%, neomycin 38.6%, streptomycin 31.8%, gentamicin 4.6%, kanamycin 4.6% and colistin 2.3%. Ps. aseruginosa was more sensitive to carbenicillin than other Pseudomonas spp isolated from spring waters in Seoul area but more resistant to kanamycin, and Ps. aureofaciens was no resistant to streptomycin. Among multiple drug resistance, resistance to 5 drugs was 31.8%, 4 drugs 15.9%, 7 drugs 13.6%, 1 drug and 2 drugs 4.6%, and 8 drugs 2.3%, respectively. The multiple resistance patterns detected highestly were NA-CB-C-TE-AMC (18.2%), NA-CB-N-C-TE-AMC (13.6%), CB-C-TE-AMC (11.4%) and NA-CB-N-C-TE-AMC-S (9.1%).
This study was performed to investigate the possible effect of Bacillus subtilis which is the predominant species of bacteria in Korean soy sauce, soy paste, and Meju (soybean cake) on the growth and aflatoxin production of Aspergillus parasiticus ATCC 15517. The microorganisms were grown in a modified APT broth and incubated at 30℃ for 12 days. Aflatoxins were determined using high performance liquid chromatography (HPLC). A remarkable inhibition of the growth of Aspergillus parasiticus was observed during the incubation period when in the presence of B. subtilis (mixed culture). Dry mycelial weight in the mixed culture was significantly reduced by 85.3% in comparison to the control at the end of the incubation period (p$lt;0.01). Lower levels of aflatoxins were found in the mixed culture than in the monoculture. At the end of the incubation period aflatoxin production was significantly inhibited by more than 50% (p$lt;0.05). These results indicate that B. subtilis mainly inhibites the growth and aflatoxin production of toxigenic Aspergillus in Meju, soy sauce and soy paste. Although its effect on aflatoxin production was less pronounced, we . could expect more inhibition by another bacteria related with fermentation in Meju.