Studies On The Effects Of Four Heavy-metals Bioaccumulation In Ganoderma Lucidum

Most edible and medicinal fungi such as Ganoderma lucidum have the characteristic of enrichment of heavy metals. The concentration of heavy metals in fruiting bodies is higher even though Ganoderma lucidum cultivated in the low heavy metals concentration filed.This article took Ganoderma lucidum as materials for experiment, and studied the ablities of accumulation and endurance, absorption of cell wall of cadmium, chemical form of cadmium in cell, the content of soluble proteins under different concentration of cadmium et al, to find out the way to reduce the content of heavy metals and provide thebase for industry development.With the concentration of cadmium added, the biomass of mycelium alsoincreased, and then decreased later with the concentration becoming higher. All the concentration are higher than the control. The degree of bioaccumulation augments slow with a low concentration of heavy metal, but becomes fast once the concentration reach a high level. The difference of affections on the biomass and heavy metal accumulation of mycelium is yielded with differences of the ways of heavy metals function, adsorption pathway, and the heavy metal endurance on mycelium.With the concentration increased (0～0.27mg/kg), the concentration of anlage and fruiting body also advanced. But it's different for lead: the tread of curve of accumulation climb up first and then went down. In lead experiment, bioaccumulation between test team and control one in fruiting body, anlage had little difference, which tell us the function of absorbing heavy metals in Ganoderma lucidum is weak.By the method of separation of cell wall from cytoplasm, the paper researched the function of absorption for cadmium. We found that the content of cadmium in cell wall was 87-90%, which indicated cell wall had a strong effect on absorption of heavy metals, and the sites of integrating cadmium have the characteristic of saturation.We took a research on chemical form of combination of cadmium in cell with a method of step-to-step, most cadmiums exist in cell with the form distilled from NaCl,HAC and HCL. Protein and pectate had pivotal effect on bioaccumulation. The content of soluble proteins in mycelium increased 24.9% than control team when the concentration is 1mg/kg. This maybe the reason that cadmium stimulated the mycelium and produced much proteins to protect organs from harms. With the concentration increased, the content of protein decreased which is because protein hanging together with cadmium reached saturation and cadmium existed in cell with dissociative form, which did harm to cell and limited the growth of mycelium.Cadmium had an active effect on SOD, and had a limited effect on POD, little remarkable effect on CAT with the concentration of experiment range.