Online ISSN : 1884-4111
Print ISSN : 0033-8303
ISSN-L : 0033-8303
Analysis of γ-ray Irradiated Pasteurized Agaricus (Agaricus blazei Murill) by ESR in Oxygen-Free Atmosphere
Hiromi KAMEYAMitsuko UKAI
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2007 Volume 56 Issue 8 Pages 437-441


Agaricus (Agaricus blazei Murill) is one of a popular crude drug in Japan and East Asia countries. The crude drugs originating from natural raw products are easy to be contaminated by microorganism. Radiation method has been introduced as the sterilization technology for crude drugs. ESR has been used for the detection of radicals in irradiated drugs. Using ESR, we detected radical species in Agaricus before and after the gamma ray pasteurization. The ESR spectrum consists of a broad sextet centered at g=2.0, a singlet at same g-value and a singlet at g=4.0.
We found that relaxation times of radicals in Agaricus varied by the presence of oxygen. Upon substitution of air by Ar, i.e., the absent of oxygen in the ESR sample tube, the T1 value became 10 times larger than the presence of oxygen. Accordingly, the progressive saturation curve indicates more immediate saturation under the Ar than air atmosphere. Radicals, produced by the γ-ray irradiation to Agaricus, are very sensitive to oxygen. We concluded that ESR spectrum of irradiated Agaricus sample in the absence of oxygen is useful for the detection of dose level of γ-ray irradiation.

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