• Journal of Food Hygiene and Safety
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• v.8 no.1
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• pp.37-53
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• 1993

F. moniliforme MRC 826, a common fungal contaminant of com, has been known to produce a group of mycotoxins, the fumonisins. By thin layer chromatography, fumonisin $B_{1}$ was detected in the F. moniliforme MRC 826 com culture material(CM) extracts. This study was performed to compare the toxicity and carcinogenicity of F. moniliforme MRC 826 CM with those of aflatoxin $B_1(AFB_1)$ in rats. The toxicity was tested over a period of 7 days in ten female Sprague-Dawley (SD) rats. Treatment group were fed a 1 : 1 mixture(wt/wt) of ground CM and basal diet in powder form, while other negative control group were given basal diet alone. The principal pathological changes in rats treated with 50% CM were hepatocellular hydropic degeneration and renal tubular necrosis. The cancer-promoting activity of CM was evaluated in the rat liver diethylnitrosamine-two thirds partial hepatectomy(DEN-PH) model for carcinogenesis. 70 male SO rats(ca. 170 g) were randomized into 5 groups. Group I served as the positive controls and received the basal diet containing 2 ppm $AFB_{1}$ group 2 received 5% CM, group 3 received 2.5% CM, group 4 received 5% normal com and group 5 received 2.5% normal com. 5% treated group showed cancer promoting activity in rat liver using DEN as initiator and the induction of glutathione S-transferase placental form positive foci as an end point after 6 weeks of promotion.

• The Journal of the Petrological Society of Korea
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• v.2 no.2
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• pp.74-94
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• 1993

Metabasites and metapelites in the Mungyong area were intruded by Cretaceous granites with radius of 4-8 km. As the distance from granite body increases, the mineral assemblage of metabasite changes from amphibole + plagioclase through amphibole + plagioclase + epidote to amphibole + plagioclase + epidote + chlorite. The compositional variations of amphibole and plagioclase according to the change of metamorphic grade and bulk rock compositions are very complex. Towards the Mungyong Cretaceous granite body, the mineral assemblage of metapelite changes from chlorite+ muscovite(ch1orite zone) through biotite + chlorite + muscovite(biotite zone) to andalusite+biotite + muscovite${\pm}$chlorite or cordierite+ biotite+ muscovite${\pm}$chlorite(cordierite zone). The estimated metamorphic conditions of cordierite zone are 480~$580^{\circ}C$ 1.5-3.3 kb. The theoretical study on the thermal metamorphism caused by the Cretaceous granite with radius longer than 4 km in the Mungyong area suggests the followings: The degree of metamorphism is mainly determined not by the size of granite body but by the temperature of granite intrusion; The country rocks within 2 km from Cretaceous granite have undergone metamorphism with temperature higher than $500^{\circ}C$, which is consistent with the petrological study in the Mungyong area. Mungyong Cretaceous granite caused a low P/T thermal metamorphism to the country rocks; the amphibolite facies metamorphism to the country rocks within 1-2 km from the granite body and the epidote-amphibolite and greenschist facies metamorphism to the country rocks within 2-5 km.