Factors Affecting the Amount of Cadmium Accumulated in Culinary-Medicinal Royal Sun Agaricus, Agaricus brasiliensis S. Wasser et al. (Agaricomycetideae), During Cultivation

Abstract

This study was conducted to investigate accumulation of heavy metals in Agaricus brasiliensis at commercial farms in Taiwan. Among 14 samples of fruiting bodies of A. brasiliensis examined, five heavy metals, Cr, As, Cd, Hg, and Pb, were detected and only the content of cadmium (Cd) exceeded the level of 2 ppm (μg/g) specified by the Department of Health, Republic of China. The rates of Cd in fruiting bodies varied with samples ranging from 1.10 μg/g to 20.07 μg/g. Accumulation of Cd in fruiting bodies varied with strains of A. brasiliensis. Among the four strains studied, the strain A5 had the lowest rate of Cd absorption (4.57 μg/g) and the highest production of fruiting bodies (4592.4 g/24 bags), making it an ideal strain for commercial production. Among six cultivation adjuvants tested, the oyster shell powder contained the highest level of cadmium. The average cadmium level in the plastic bag was 0.077 μg/g, whereas the cadmium content in oyster shell powder was 0.363 μg/g. This study indicates that the oyster shell powder in the growth substrate may be one of the main sources for the accumulation of cadmium in the fruiting body of A. brasiliensis.