Preliminary Investigation for Inspection of Carcinogenic Mycotoxin Contamination in Foods and Herbal Drugs.

1990 Fiscal Year Final Research Report Summary

• Project/Area Number: 01571199
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: Biological pharmacy
• Research Institution: Toyama Medical and Pharmaceutical University
• Principal Investigator: SAKAI Tatsuo Toyama Med. & Pharm. Univ. Pharm. Sci., Assistant professor, 薬学部, 助教授 (90019109)
• Co-Investigator(Kenkyū-buntansha): TAKEBE Sachiko Toyama Med. & Pharm. Univ. Pharm. Sci., Professor Research associate, 薬学部, 助手 (20135031) ; KOBASHI Kyoichi Toyama Med. & Pharm. Univ. Pharm. Sci., Professor, 薬学部, 教授 (80019108)
• Project Period (FY): 1989 – 1990
• Keywords: Mycotoxin / Aflatoxin / Aflatoxinogenic fungi / Herbal drug / Moutan bark / Paeonol

Research Abstract

Growth and toxin production of aflatoxinogenic fungi on major plant herbal drugs were investigated for inspection and survey of aflatoxin (AF) contamination in herbal drugs.
Each sample powder or intact sample of herbal drugs was inoculated with aflatoxinogenic strains of aspergilli and incubated. Among sixty-two samples of herbal drugs examined, active fungal growth and marked production of AF were recognized on ten. These contain large quantities of starch and glucides or lipids. Thus, it was assumed that these herbal drugs susceptible to AF contamination.
On the other twenty-one samples, the fungi did not grow actively. AF production was low or not detected, in spite of active fungal growth, on another thirty-one samples. These results suggest that many herbal drugs have inhibitory effect on the fungal growth and AF production. The methanol extract of twenty-five samples was added to a powdered medium designed for investigation of the fungal growth and AF production at various concentrations.
In Moutan bark and Magnolia bark, the fungal growth and AF production were remarkably inhibited. In Phellodendron bark, Coptis Rhizome, and Glycyrrhiza, the fungal growth was active but AF production was reduced. From an extract of Moutan bark, paeonol was isolated as the inhibitory constituent. Magnolol and honokiol from Magnolia bark showed marked and almost complete inhibition, respectively, of the fungal growth and AF production. Berberine and glycyrrhetic acid did not inhibit fungal growth, but did inhibit AF production.
In Perilla herb, the production of AF B group was much higher than that of AF G group. When the methanol extract of Perilla herb was added to the powdered medium, AF B level increased, while AF G level decreased dependent upon the concentration of the extract. Two active substances were isolated from Perilla herb and identified as dill apiole and elemicin. This effect was also found in myristicin, Known to be a constituent of Perilla herb.