In vitro antimutagenic activity of methanol extract from brown rice and its physico-chemical characteristics were investigated using Salmonella typhimurium reversion assay and SOS chromoteat. Methanol extracts of brown rice were not mutagenic compared with direct and indirect mutagenicities of 4NQO (4-nitraquinoline oxide), 2NF(2-nitrofluorene), Trp-p-1(3-Amino-1,4-dimethyl-SH-pyrido-[4,3-b]indole), and Trp-p-2(3-Amino-l-methyl-SH-pyrido[4,3-b] indole). Antimutagenic activity against the indirect mutagenicitiea induced by Trp-p-1, Trp-p-2 and AFB₁ (aflatoxin B₁) was found in methanol extract. Even though antimutagenic activity showed dose-dependent, it remained constant at inhibition rate ranging 60%-90% when the concentration was above 3mg/plate in the S. typhimurium reversion assay and 0.2-0.6 mg/assay in the SOS chromotest. The antimutagenic activity of the methanol extracts was stable at various pH (2, 7 and 10), temperatures (60, 80 and 100℃) and heating times (2, 4, 6, 8 and 10 min at 100℃).
In order to develop a natural food preservative, the root bark of Morus alba was extracted with several solvents, and then antimicrobial activity was investigated. The optimum extracting condition for the antimicrobial substance from the sample, minimum inhibitory concentration (MIC) of the extracted substance against microorganisms were also examined. The antimicrobial activity of the ethanol extract from the sample was atronger than those of the extracts by the other solvents such as water, methanol, ethyl acetate and acetone. The optimum extracting condition for antimicrobial substance from the sample was shaking extraction twice for 5 hours at room temperature in case of 7 times of absolute ethanol added to the crushed root bark of Morus albs. The ethanol extract from the root bark of Mores albs had strong antimicrobial activity against Gram positive bacteria(MIC, 6.4-19.2 g/ml) such as B. subtilis, B. cereus, L. monocytogenes and S. aureus. Especially, Bacillus species was the most susceptible to the extracted substance. The ethanol extract showed antimicrobial activity against Gram negative bacteria(MIC, 160-1600 g/ml) and yeasts(MIC, 1600 g/ml) such as C. albicans and S. acidifaeciens. The extract also showed growth inhibition against molds such as A. niger, A. parasiticus, A. versicolar and T. uiride.
The ethanol extract from the root bark of Mores alba showed the strongest antimicrobial activity on the growth of almost all the tested microorganisms which were foodborne pathogens d food-related microorganiama. Therefore, fatty acid composition, amino acid composition and shape change of microorganisms treated with the ethanol extract from the root bark of Mores alba were examined. In effects of treatment with the ethanol extract on the fatty acid compositions of B. aubtilis, S. aureus and E. coli, fatty aicd compositions such as hexadecanoic acid (16:0) and octadecanoic acid (18:0)/octadecadienoic acid (18:2) of the tested strains were increased but pentadecanoic acid (15:0), heptadecanoic acid (17:0) and octadecenoic acid (18:1) of E. subtilis, pentadecanoic acid (15:0) of S. ctureus and hexadecenoic acid (16:1) and octadecenoic acid (18:1) of E. coli were decreased. The ethanol extract did not significantly affect the amino acid composition of the tested strains. Tranamisaion electron micrographa of microorganisms treated with the ethanol extract exhibited morphological changes that irregularly contracted cell surface in S. aureus and destructed cell walls in B. subtilis and E. coli.
In the study, attempts were made to investigate the safety of the deep-fried instant noodles. A total of 50 deep-fried instant noodles were puchased from a local supermarket. Acid value, peroxide value, preservatives, heavy metals and pesticide residues were determined. Acid value(AV) and peroxide value(POV) of deep-fried instant noodles were lower than the Food Law in force. Any preservatives were not detected in all deep-fried instant noodles. The level of all heavy metals and pesticide residues found in deep-fried instant noodles were fairly low, and pesticide residues in deep-fried instant noodles was almost removed after cooking. It was conclued from these results that deep-fried instant noodles may be no harmful in oxidative stability(AV, POV) and sanitary safety(preservatives, heavy metals and pesticides).
The present study has been undertaken to investigate the effects of garlic added to food on the activities of several enzymes in serum of rats fed lard and alcohol. Thirty-five males of Sprague-Dawley strains weighed about 130g were divided into 7 groups, each group receiving a different diet for 10 weeks; i.e. basal diet plus 15% lard, basal diet plus 5010 alcohol, basal diet plus 0.5% garlic, basal diet plus 15% lard and 0.5% garlic. Determinations were carried out on the net weight gain, food efficiency ratio, weight of organs, and AST, ALT, lactate dehydrogenase, alkaline phoaphatase activities in serum of rata. The results obtained were as follows: Rats given feed containing lard and alcohol showed significant decrease in net weight gain, but garlic 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 garlic feeding decreased enzyme activities compared to lard and alcohol containing group. The above results suggest that garlic would prevent the metabolic disease of liver by improving hyperlipemia caused by high fat diet.
Piperine, component of pure ground black pepper, has strong stimulative and trot. Analytical method for piperine was developed by high performance liquid chromatography. Analytical conditions are as follows; mobile phase is 70% methanol, detector LTV 343 nm (0.05 AuFa), column is Novapak 5 C_(10) (15 cm × 4.6 mm), flow rate is 1.0 ml/min, chart speed is 0.25 cm/ min and intjection volume is 20 Etl. Analytical results are as follows that relative standard deviation is 1.15%, calibration curve is y=170473.1×-7848.5 (R²=0.999) that shows good linearity. Standard solution of piperine is stable up to 10 hr and content of piperine in pure ground black pepper is 4.97±0.86%. Retention time of piperine in HPLC method is about 7 min. Therefore, the developed HPLC method including simple pretreatment of sample will be contribute to quality management.
The distribution of bacteria in kimbab and its ingredients have been investigated. The total bacterial counts were over 3 × l0³/g(n=30) when the kimbabs were delivered to restaurant and it e×ceeded the legal level 1 × 10^5/g defined by the Code of Food Standard in 1991. The gram-negative coliforms were also detected 1.9 × 10^5/g. In order to study the cause of bacterial contamination in kimbabs, the ingredients used in kimbabs were examined. The bacterial counts were found 10⁴-10^5/g for kim (layer), 10⁴-l0^5/g for sausage, 10⁴-l0^6/g for boiled-spinach, 10³-10^7/g for carrot, and 10³-10^6/g for Danmyji, respectively. From these results it could be concluded that the bacterial contamination in Kimbabs was caused mainly by the ingredients such as kim, boiled-spinach, carrot, and sausage. Therefore, this suggested that the sanitary manufacture of kim, the storage at refrigerator temperature of the ingredients for kimbabs, and the proper treatment of equipments should be maintained in order to reduce the bacterial contamination for kimbaba. Furthermore, it should be required to obtain the basal data for establishment of the sanitary standard of kim and kimbab.
Water extract, and methanol extract, its chloroform and hexane fractions, and estragole from Agastache rugosa O. Kuntze were tested to find the inhibiting effect on the growth of several microorganisms. The organisms used were: Escherichia coli ATCC 1129, Staphylococcus aureus 1AM 1011, Vibrio parahaemolyticus WP, Bacillus aubtilis ATCC 6633, Aspergillus oryzae KFCC 890, Aspergidlus niger KCCM 11240. Water and methanol extracts at the concentration of 0.5%, and chloroform and hexane fractions at the concentration of 0.05% inhibited the growth of microorganisms from 1/5 to 2/3 of the control group. Eatregole identified from the hexane fraction as a major component, its authentic compound completely inhibited the growth of Vibrio parahaemolyticus completely at the concentration of 0.03%, and the other bacteria were at 0.05% .
Analytical method for synephrine and octopamine in citrus fruits, drinks containing citrus fruit, and human urine was developed using gas chromatography / mass spectrometry(GC/MS). Silylation with MSTFA, acetylation with MBTFA, and trimethylailylation with MSTFA followed by tritluoroacetylation with MBTFA were compared. The selective derivatization of aynephrine and octopamine was optimized with two derivatizing reagents ; MSTFA and MBTFA. The ion at mlz 267 was monitored to characterize the benzyl group of the both compounds. Synephrine was detected in the concentrations of 0.46-1.88 ug/g for citrus fruits and 1.2-8.1 ug/ml for drinks. The urinary excretion data of aynephrine showed the highest concentration at the period of 8-20 hours after drinking orange juices and total amounts of its urinary excretion calculated as a parent compound was 11-14% of a dose during 48 hours. Octopamine was not detected in citrus fruits, drinks, and human urine.