This study was designed to observe the effects of T-2 toxin on total cholesterol and lipid concentration in rat serum. T-2 toxin is a secondary metabolite produced by Fusa~rdum sp. which is often found on agricultural products including cereals, and it is a causal material of liver injuries in cattle and humans. When we fed rats with standard diet treated with T-2 toxin, the body weight and feed consumption of rats treated with T-2 toxin were decreased. As the results of lipid analysis, the concentrations of total cholesterol and free cholesterol in serum of treated rats were increased compared to non-fed control group, On the other hand, the levels of triglyceride and phospholipid in the serum of T-2 toxin treated experimental groups were declined. In conclusion, T-2 toxin largely influenced on the total cholesterol and lipid levels in rat serum.
The relationships between storage stability and chlorophyll contents of dried laver(DL), roasted laver(RL) and roasted seasoned laver(RSL) according to packaging during storage at 20 0.51 were investigated by measuring the acid value(A and the peroxide value(POV). The results are as follows; 1.The storage stability was decreased in the rank of 0 $lt; 3 $lt; 6 $lt; 9 months by storage term, RL $lt; DL $lt; RSL by the kind of layer products and PP/PE/AL/PE/ LLDPE(Al) $lt; PP/PE(PP) by packaging. 2. When the silica gel was added to RSL, the storage stability was improved. The more the addition level of silica gel was increased, the more the storage stability was improved. The rank order was 2g $lt; 4g in RSL. 3. Reduction of the total chlorophyll content in RSL were deacreased to 10% when packed with A1 and 24% when packed with PP.
Analytical method for preservatives in food was developed using gas chromatography/mass spectrometry (GC/MS). Propionic acid, sorbic acid, benzoic acid, ethyl salicylate, ethyl p-hydroxy benzoate, iso-propyl p-hydro benzoate, n-propyl p-hydroxy benzoate, iso-butyl phydroxy benzoate, n-butyl p-hydroxy benzoate, p-hydroxy benzoic acid and dehydro acetic acid were extracted from cooling beverage with diethyl ether. The polar hydroxyl and carboryl groups of food preservatives were derivatized with N-methyl-N-tent-butyldimethylsilyl-trifluoroacetamide (MTBSTFA) to form the corresponding tert-butyldimethyl-silylated derivatives, and submitted to GC/MS analysis. The mass spectra of the derivatives were investigated for the selection of monitoring ions for multi-residue analysis of 11 preservatives by GC/MS. The macro program was also developed for the qualitative analysis of these preservatives in food.
The present study was performed to investigate the bioconcentration of BPMC, chlorothalonil, dichlorvos and methidathion. The BCFs(bioconcentration factors) and depuration rate constants for four pesticides in zebrafish(bracJxydanio rerio) were measured under semi-static conditions(OECD guideline 305-B) in a concentration of one-hundredth of the 96 hours LC_(50) of each pesticide at the equilibrium condition. The results obtained are summarized as follows : The BCFs of BPMC, chlorothalonil, dichlorvos and methidathion were 1.44±0.09, 2.223±0.063, 0.81±0.08 and 5.53±0.13, respectively. Depuration rate constants of BPMC, chlorothalonil, dichlorvos and methidathion were 0.028, 0.015, 0.220 and 0.152, respectively. The concentrations of BPMC, dichlorvos and methidathion in zebrafish reached an equilibrium in 3 days, and the equilibrium of chlorothalonil was reached after 14 days. Depuration rate of dichlorvos was the fastest followed by methidathion, BPMC and chlorothalonil. The lower BCF of BPMC was due to its relatively high K_(OW), slow K_(DEP), and low S_W and V_P, compared to chlorothalonil and methidathion. The BCF of chlorothalonil was much lower than that expected on the basis of high K_(OW) slow K_(DEP), low S_W and V_P. The reason is that the experimental concentration for chlorothalonil is 1/100 - 1/1000 lower than that of BPMC, dichlorvos and methidathion. The BCF of dichlorvos was lower than that of other pesticides due to its very rapid K_(DEP), very high V_P and S_W, and very low K_(OW). The BCF of methidathion was higher than that of other pesticides due to its very low V_P and S_W. Therefore, these data suggest that physicochemical properties of pesticides may be important in the bioconcentration.
This study was undertaken to evaluate antioxidative activities of substances isolated from marine resources against human low density lipoprotein (LDL). Methanol-water extract (80:20, v/v) of Sargassum ringgoldianum had the highest antioxidant activity and the active substance was purified by silica gel column chromatography by eluting chlorform : methanol mixture (80:20, v/v). The active fraction was separated to several spots on the TLC in chloroform : methanol (10:1, v/v) mixture. Antioxidative activity of band 4 of fraction 2 on TLC was highest than that of a-tocopherol against human LDL oxidation by the method of thiobarbituric acid reactive substance (TBARS). The band 4 of fraction 2 inhibited the copper mediated oxidation of human LDL with almost completely at 1 or 2 mg/ml.
Microbial populations of total aerobic bacteria -and coliforming bacteria, TBA, Hunter's color value, heme pigments, muscle protein solubility, cooking loss and shear force were investigated for evaluating the shelf life of chicken legs gamma-irradiated at doses of 1, 3, 5 and 10 kGy with air-contained and vacuum-packaged methods. The initial microbial populations decreased with gamma irradiation depending upon the dose, and microorganisms in the vacuum-packaged samples were inhibited more than those in the air-contained samples. TBA values were higher in the air-contained samples than in the vacuum-packaged samples. Hunter's L and a values of the surface and inside of the legs increased by gamma irradiation, showing a bright red color and the red color was maintained during the storage of both samples. The concentrations of oxymyoglobin among the heme pigments increased by gamma irradiation. Muscle protein solubility slightly increased by increasing the applied dose. There were no significant differences in the cooking loss and shear force values. In conclusion, the combination of gamma irradiation and vacuum-packaging could extend the shelf life of chilled chicken without deterioration of the quality.
In order to screen the antagonistic bacteria which inhibit the growth of the apple pathogen, Penicillum expansum, we isolated an effective bacterial strain and investigated into the antifungal activity of the antagonist and it's identification. The eleven strains of bacteria which strongly inhibited P. expansum were isolated from the nature, and the best antagonistic bacterial strain designated as CH142, was selected. The antagonistic strain CH142 was identified to be the genus Bacillus subtilis based on morphological and biochemical characterization. The CH142 showed 55.9% of antifungal activity against the growth of P. expansum. By the treatment of the culture broth and the heat treated culture filtrate of it, the B. subtilis CH142 showed 90% and 15% of antifungal activity, respectively.
Previous studies have shown that methanol extract and its butanol fraction of Carthamus tinctorius L. Semen have the hepatoprotective effect on the CCl₄-induced hepatotoxicity. The hepatoprotective effect of subfractions has been evaluated by analyzing blood and hepatocyte biochemical analyses and biotransformation enzyme analyses. Treatment of BS-5 subfraction has significantly decreased the activities of alanine aminotransferase and aspartate aminotransferase. In addition, the levels of cholesterol and triglyceride in liver have been decreased as compared with that of CCl₄ treated rats. The hepatoprotective effect of BS-5 subfraction on the CCl₄-induced hepatotocicity would be mediated of the attenuation of the level of cytochrome P450 and the enhancement of the activity of glutathion S-transferase.
Previous studies have shown that methanol extract and its butanol fraction of Carthamus tinctorius L. Semen have the hepatoprotective effect on the CCl₄ induced hepatotoxicity. The hepatoprotective effect of the subfractions of butanol fraction has been evaluated by analyzing oxygen free radical scavenging enzyme activities and histopathological examinations. In BS-5 subfraction treated group, the activity of superoxide dismutase has been significantly increased as compared with that of CCl₄ treated rats. Antioxidant activity has been evaluated by the examination of the scavenging activity against 1,1-diphenyl-2-picrylhydrazyl radical. BS-5 subfraction has shown strong antioxidant activities. The histopathological examination showed that the treatment of BS-5 subfraction has relieved the ballooning degeneration of hepatocytes which had been generated by CCl₄. It appears that the protective effect of BS-5 subfraction would be mediated of the attenuation of lipid peroxidation by acting as a free radical scavenger, which were based on the increase of superoxide dismutase activity.
The Budget method used currently in Codex for estimation of use levels of food additives was investigated and the specific approach that can be applicable for Koreans has been proposed. Theoretical maximum daily intakes(TMDIs) of benzoate, p-hydroxybenzoic acid ester, butylated hydroxyanisole(BHA), butylated hydroxytoluene (BHT), t-butylhydroquinone(TBHQ), nitrite, nitrate, sorbate, and sulfite were estimated and compared with corresponding acceptable daily intakes(ADIs). Additives requiring further precise evaluation were screened. TMDIs of benzoate, BHA, BHT, TBHQ, nitrite, and sulfite exceeded ADIs. On the other hand, it appeared that TMDIs of p-hydroxybenzoic acid esters, nitrate, and sorbate were below ADIs. It is expected that the Budget method may be used as one approach for the estimation of use level and risk assessment.
The present study has been undertaken to investigate the effects of crude ginseng extract added to food on the lipid composition 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 0.5% crude ginseng extract, basal diet plus 15% lard and 0.5% crude ginseng extract. Determinations were carried out on the net weight gain, food efficiency ratio, weight of organs, triglyceride, total cholesterol, HDL-cholesterol, free cholesterol. The results obtained were as follows: 1. Rats given feed containing lard and alcohol showed significant decrease in net weight gain, but crude ginseng extract caused an increase in food efficiency ratio. 2. Lard supplementation group showed increase in the weight of liver, kidney, spleen, but another groups did not. 3. The contents ratio of triglyceride, total cholesterol in serum of lard-fed group showed significant increase compared to controls and but the simultaneous supplementation of crude ginseng extract and lard decreased sinificantly than those of lard-fed group. 4. The contents of free-cholesterol and ester cholesterol in serum of the simultaneous supplementation of crude ginseng extract group decreased as compared with the lard single fed group. 5. Crude ginseng extract single-fed group showed increse of plasma HDL-cholesterol compared to the control but not in any other groups. 6. The ratio of contents of VLDL, LDL-cholesterol and HDL-cholesterol in serum was significantly high in the only lard containing group and alcohol group, the crude ginseng extract supplemented group was showed lower tendency than only lard and alcohol group. The above results suggest that crude ginseng extract would prevent the metabolic disease by improving hyperlipidemia.
Limited information is available on the acceptability of Korean MRLs(maximum residue limits) and the health risk based on the pesticide exposure by food intake. The aim of this study was to evaluate TMDI(theoretical maximum daily intake) and EDI(estimated daily intake) for Korean by using MRLs, food intake, residue data, and correction factors, and compare with ADI(acceptable daily intake) in order to estimate the health risk based on the pesticide exposure. The study was performed in three steps. In the first step, the residual pesticides in each category of food were investigated using the pesticide residue analytical data(1995-96) from officially approved organizations and the analytical data for poultry was adopted from Korean food code method. In the second step, TMDI was estimated from MRLs and food factors, and was compared with ADI. In the third step, the effectiveness of each culinary treatment (washing, peeling, steaming, boiling, and salting) was evaluated and EDI was calculated using pesticide residue data, food factor, and correction factor by treatment. TMDI obtained from MRLs and food intake, and food intake was summed as 1,100.99 g, which was 79.1% of total consumption. The percent ratio of TMDI to ADI for 156 pesticides was mostly below 80% and only 30 pesticides exceeded the ADI. In particular, non-treated EDI from pesticide residue data and food intake was summed up to about 43 ug/day/capita, and the rank was procymidone(8.6 ug) $gt; malefic hydrazide(8.2 ug) $gt; EPN(3.7 ug) $gt; deltamethrin(3.5 ug) $gt; cypermethrin(3.0 ug). The treated EDI calculated from pesticide residue data, food intake, and correction factor by culinary treatment was summed up to 13.7ug/day/capita. The percentage of ADI was TMDI(79.74%) $gt; non-treated EDI (0.17%) $gt; treated EDI(0.04%), and the exposure level of Korean population to whole pesticides was below the level to produce health risk. Oncogenic risk of five pesticides used in Korea whose oncogenic potency(Q*) was known were assessed from TMDI and treated EDI. Dietary oncogenic risk for Korean was estimated to be 2.0 × 10^(-3) on the basis of TMDI, 8.3 × 10^(-7) on the basis of treated EDI. The oncogenic risk from TMDI exceeded the risk level(1 × 10^(-6)) of EPA, whereas the oncogenic risk from treated EDI and real exposure level was lower than that of EPA.
Safety of present food has been accepted on the basis of extensive use and experience for a long time. Many food resources have been developed by traditional techniques without any significant adverse impacts on the safety of food. Recently recombinant DNA techniques are being used to develop new food resources. These techniques enable developers to make specific genetic modifications in food resources that introduce substances that could not be introduced by traditional methods. With these techniques food resources are being to resist pests and disease, to tolerate herbicides, and to have improved characteristics for food preservation and nutritional contents. Because the properties of an organism result from interaction between biochemical pathways controlled by many genes, the genes conferring these traits usually encode directly responsible proteins for the new trait as well as proteins that indirectly modify carbohydrates or lipids in food. Therefore, this kind of food is regarded as new food that has not been existed before, and the safety of the food developed by recombinant DNA techniques should be evaluated upon scientific basis. In this paper, the issues upon safety of the food developed by gene manipulation are discussed in terms of composional changes that can be introduced, potential food safety harzards that might arise, present status of safety regulations in various countries and international organizations, and suggestions for the safety regulation in Korea.