It is thought that aflatoxin in one of causative agents in the development of hepatocellular carcinoma. Aflatoxins are secondary metabolites of the molds, most commonly Aspergillus flavus and Aspergillus parasiticus, and have been found in a
number
of
agricultural products such as cereals and nuts. These fungi are widely distributed but in order to synthetize the toxin, the fungi need high temperature and humidity, such environmental conditions as tropical and subtropical areas of the Africa,
the
southern China, the south east of the United States, Although incidents of acute aflatoxin poisoning in humans are rare, prolonged exposure to sub-acute or chronic levels is likely to be particulary serious in developing countries where poor food
storage under environmental conditions likely to favour toxin synthesis is common.
Considerable evidences has been accumulated implication the exposure of aflatoxin as an important factor that contributes to hepatocellular carcinoma of humans in certain regions of the world. Epidemiological study on the measurement of aflatoxin
in
human body fluids was first in Korea, and it has been rarely reported in the world. However, the role of aflatoxin on hepatocellular carcinoma of humans is also complicated by the strong correlation of hepatitis B virus infections in endemic
areas.
Inte
action between these two important factors has been postulated. To test the hypothesis of the interaction of aflatoxin with hepatitis virus infection as well as other factors that may also contribute to liver cancer in humans, it is necessary to
develop
a-rapid and test to monitor the aflatoxin metabolites in human body fluids so that a direct measurement of the exposure can be achieved. Such a need was highlighted by a workshop sponsored by the WHO in 1984.
In general, thin layer chromatography and high performance liquid chromatography are most commonly used to analyze aflatoxin and its metabolites. However, these methods are not specific and need extensive cleanup as well as expensive instruments;
thus
are inadequate to use in large scale epidemiological studies With the development of a sensitive, specific, and a simple immunochemical methods, it is now possible to monitor aflatoxin and its metabolites in body fluids. So we have analyzed urine
for
aflatoxin by use of competitive direct enzyme linked immunosorbent assay referred to Pestka et al.
A total of 116 urine samples were collected from the patients at Gyeong-Sang National University Hospital during the period of Nov. 1 1989 to Feb. 30 1990. There were 48 cases of liver cirrhosis, 20 cases of hepatoma, and 48 cases of normal
control
which were shown to have checked up by use of routine laboratory work-up.
1) Enzyme-linked immunosorbent assay for aflatoxin is rapid, simple and safe method.
2) Antiserum in rabbit which was produced against Aflatoxin B1 oxime BSA reached the peak level of antibody titer on 13 weeks after immunization of antigen and showed high titer at 1,000 times dilution in rabbit A.
3) Antiserum produced by aflatoxin B1, lesser extent with aflatoxin G,(28%), aflatoxin G(36%) and almost none to aflatoxin. M1.
4) Potential interference in the ELISA by the sample extract was tested by comparing the standard curve and curve prepared in spike methanol PBS-dimethylformamide extracts of sample. But there were no interference which influenced on results.
5) Aflatoxin positive urines were 4 samples out of all 116 urine samples(ca. 3.45%) There were 2 cases of liver cirrhosis(4.16%), 1 case of hepatoma(5.00%), and 1 case of normal control(2.08%), H-17 sample showed the highest aflatoxin B1 content
of
0.153±0.027(ng/ml), the remainders were L-22: 0.136±0.034, N-3:0.092±0.024, L-25: 0.063±0.019(ng/ml), respectively.
6) There were no difference of aflatoxin B1 level among the diseases.
7) There is a possibility that Korean were exposed to considerable amounts of aflatoxin in their diet.
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