• Journal of Food Hygiene and Safety
• /
• v.7 no.2
• /
• pp.99-106
• /
• 1992

To prevent food-poisoning outbreaks by Vibrio vulnificus the antimicrobial efficacy of grapefruit seed extract (GFSE) was examined. Minimal inhibitory concentration (in vitro) for the microorganism was found to be 50∼100 ppm. Transmission electron micrographs of Vibrio vulnificus showed the biocidal action of this natural antimicrobial agent would be related to specific respiratory effect coupled with the destruction of permeable function of microbial cell membrane. After Anguilla japonica GFSE-injected to the body was incubated in the seawater contaminated by Vibrio vulnifiucs the fish meats were taken up, mixed with control diet and used as a diet in the feeding experiment. In this experiment the effect of GFSE treated with fish muscle on body weight, protein efficiency ratio, serum enzymes and serum blood components of broiler chicks was investigated. It is proved from this study that there is neither Vibriosis nor toxicity associated with GFSE itself an fish meats treated with it when it is injected to the fish body at a level of 250 ppm or less.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.3
• /
• pp.332-339
• /
• 2005

The effect of transinoculation of goat rumen liquor into sheep rumen on mimosine toxicity was studied. One adult Kutchi male goat having higher mimosine degradation capacity than sheep was gradually adapted to Leucaena leucocephala (Leucaena) leaves by feeding increasing level of eucaena leaves supplementation for 1 month. Six Bharat Merino rams (12-18 months of age) were divided into two equal groups with (group I) or without (group II) infusion of 200 ml of goat rumen liquor per animal. The mimosine degradation in groups I and II were 3.04 and 2.31; 3.90 and 3.73 mg per day per 10 ml rumen liquor respectively after 1 and 2 weeks of leucaena feeding leaves. Total rumen bacterial population in RGCA medium and in a selective medium containing iron showed an increasing trend in both groups, while the bacterial population growing in the presence of cellulose showed a decreasing trend. Animal performance data did not show any adverse effect. Results revealed that transinoculation of rumen liquor from leucaena leaves adapted goat to sheep rumen did not help to improve mimosine degradation in the sheep. The sheep transinoculated with goat rumen liquor displayed no in vivo improvements in nutrient utilization vis-a-vis mimosine metabolism.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.11a
• /
• pp.397-400
• /
• 2008

Traditional propellants which have a hypergolic characteristic have a high performance but also have disadvantages of toxicity and complex handling requirement. In order to replace these propellants, one of the alternatives is hydrogen peroxide which generates high temperature oxygen and water vapor after catalytic reaction. In this paper, autoignition characteristics of kerosene by decomposed hydrogen peroxide were investigated to perform fundamental research for designing a thruster using hydrogen peroxide and kerosene propellants. Contraction ratio, whether flame holder exists or not, and feeding pressure of propellants were selected as variables. From the experiments for different mixture ratio, we confirmed the ignition stability is strongly affected by a feeding pressure of propellants.

• Korean Journal of Ecology and Environment
• /
• v.41 no.4
• /
• pp.431-440
• /
• 2008

Turbid water or suspended sediment is associated with negative effects on aquatic organisms; fish, aquatic invertebrate, and periphyton. Effects of turbid water on fish differ depending on their developmental stage and a level of turbidity. Low turbid water may cause feeding and predation rates, reaction distance, and avoidance in fish, and it could make fish to die under high turbidity and long period. Therefore, it is very important to find out how turbid water or suspended sediment can affect fish in domestic watersheds. The objectives of this study were 1) to introduce international case studies and their standards to deal with suspended sediment, 2) to determine acute toxicity in 4 major freshwater fishes, and 3) to determine in relation to adverse effect of macroinvertebrates and fish. Impacts of turbid water on fish can be categorized into direct and indirect effects, and some factors such as duration and frequency of exposure, toxicity, temperature, life stage of fish, size of particle, time of occurrence, availability of and access to refugia, etc, play important role to decide magnitude of effect. A review of turbidity standard in USA, Canada, and Europe indicated that each standard varied with natural condition, and Alaska allowed liberal increase of turbidity over natural conditions in streams. Even though acute toxicity with four different species did not show any fatal effect, it should be considered to conduct a chronic test (long-term) for more detailed assessment. Compared to the control, dominance index of macroinvertebrates was greater in the turbid site, whereas biotic index, species diversity index, species richness index, and ecological score were smaller in the turbid site. According to histopathological analysis with gills of macroinvertebrate and fishes, morphological and physiological modification of gills due to suspended sediments can cause disturbance of respiration, excretion and secretion. In conclusion, in order to maintain good and healthy aquatic ecosystem, it is the best to minimize or prevent impact by occurrence of turbid water in stream and reservoir. We must make every effort to maintain and manage healthy aquatic ecosystem with additional investigation using various assessment tools and periodic biomonitoring of fish.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.23 no.3
• /
• pp.380-386
• /
• 1994

The behavior of glycogen and histological changes of hepatic tissues in the liver of rats, aged 6 to 7 weeks, fed 18% casein diet under control, gramoxone and gramoxone + vitamin C(Vt. C) diets has been investigated in a comined histropathological and histochemical studies. Cloudy swelling and fat changes of hepatic cells were observed in the gramoxone group with the duration of feeding time. Fat changes of hepatic cells were observed more obviously than cloudy welling, especially in the hepatic cells of periportal area. The number of Kupffer's cells increased signifciantly in the gramoxone group fed for 4weeks. The cloudy swelling and fat changes decreased obviously in the gramxone + Vt. C group. Glycogen content of heaptic cells tended to increase slightly in the gramoxone group as compared with the control group . moreover, glycogen depositons were higher in the hepatic cells where fat changes were obvious. It seems to be that Vt.C alleviating effects on the gramoxone toxicity in the patterns of glycogen distribution and histological structure of heaptic tissues.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.51 no.spc1
• /
• pp.1-6
• /
• 2006

Rice is the most important crop in Korea and its annual production of 5.2 million ton is followed by over 0.5 million ton of bran as by-products of milling process. Although rice bran contains various nutritious and pharmaceutical compounds, rice brans are rarely utilized as functional food sources in Korea. In recent, tocotrienols are well known having distinctive pharmaceutical effectiveness. So tocotrienols extracted from rice bran oil were evaluated about Pharmaceutical function. The $IC_{50}$ of tocotrienols products against liver cancer, HepG2 cells were $149mg\;mL^{-1}$, indicating anticancer activity of final products. By animal feeding tests, the final products containing tocotrienols did not induce any toxicity signs in mortality, Incidence of clinical signs, body weight, etc. after a single oral administration, which proved safety of the tocotrienol products. In conclusion, tocotrienol extracted from rice bran has pharmaceutical activity without any toxic effects, which is also suggested tocotrienol products may be a good fortifying nutrition far the health and medical care.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.53 no.3
• /
• pp.451-455
• /
• 2020

This study evaluated acute toxicity of chlorine dioxide (ClO₂ ) to juveniles of black seabream Acanthopagrus schlegelii (19.4±2.3 g, 10.7±0.4 cm) and red seabream Pagrus major (74.9±8.2 g, 15.9±1.0 cm). Thirty juveniles for each species were exposed to target ClO₂ concentrations of 0, 0.05, 0.1, 0.125, 0.15, 0.2, 0.3, 0.4, and 0.5 mg/L in triplicate for eight days. Half lethal concentrations for 96 hours were found at 0.14 and 0.24 mg ClO₂/L for black seabream and red seabream, respectively. Red seabream larger than black seabream in body weight appears to be more resistance to chlorine dioxide. However, regardless of species or size, specific loading rates of chlorine dioxide to total fish weight (daily feeding amount of ClO₂/total fish weight) were similar, showing 1.3 and 1.1 g ClO₂/kg fish·day^-1 for black seabream and red seabream.

• Proceedings of the Korean Society of Toxicology Conference
• /
• 1997.05a
• /
• pp.20-27
• /
• 1997

Chinin is the second most plentiful natural polymer. Currently, chitin and chitosan are manufactured commercially in large scale from crab and shrimp shell as fish processing waste. They is being used in many commercial application because of their various functional properties. Chitosan, in particular, is being evaluated as biomedical materials in a number of food and pharmaceutical industries. Despite their potential abilities, the perfect safety had been demonstrated until now. However, the long-term feeding with chitin was not any negative effect the body weights and serum enzymatic activities in mice. And, in rats supplied with $5\%$ of chitosan diet for 450 days, there was no changes of Ca concentration in blood, bone and other organs except for in muscle. Consequently, there was no direct toxicity of chitin and chitosan against some animals such as rat and mouse by recently reports.

• Journal of Food Hygiene and Safety
• /
• v.27 no.3
• /
• pp.306-311
• /
• 2012

Stevioside, a natural sweeteners presently used in various kinds of food and food products in Korea, was evaluated for its toxicity potential in the 14 day feeding study using B6C3F1 mice. Stevioside was added to the diet at different concentrations of 0.31, 0.62, 1.25, 2.5 and 5%, and was administered for 14 consecutive days. An increase of liver organ weight in male mice was observed. No diet-related differences were noted in clinical signs, food consumption, and gross and histopatholgical evaluation. Based on these results, we concluded that the concentration of 5% in the diet was a suitable maximum tolerable dose of stevioside for a 90 day study in mice.

• Journal of The Korean Society of Clinical Toxicology
• /
• v.13 no.1
• /
• pp.43-45
• /
• 2015

Sulfoxaflor is the first insecticide belonging to the sulfoximine class and is efficient against sap-feeding insects that are resistant to other insecticides. Sulfoxaflor acts as a neurotoxin to the central nervous system of insects compared with very low toxicity to mammalian. We report on a case of a 67-year-old male who ingested insecticide and received conservative treatment for mild metabolic acidosis and gastrointestinal symptoms.