Toxic heavy metal bioremediation potential of Pleurotus ostreatus fruit bodies grown in sugarcane bagasse supplemented substrate

Fungiculture or Mushroom Cultivation is rapidly expanding throughout the world. The remarkable nutritional value and growing demand in the market further accelerate its prominence. The method of cultivation does not demand a lot of space and the per unit production is very high compared to other crops. It has been speculated that bagasse, which is the byproduct left after extracting the juice from sugarcane, can be used as an excellent substrate due to its high carbohydrate and mineral content. In the experiment, spawns of Oyster mushrooms were inoculated in bagasse collected from industries. Remarkable growth of mushrooms in a short period was observed. However, the metal toxicity being our primary concern in this experiment, the AAS (Atomic Absorption Spectrometry) Test was used to detect the heavy metal ion concentrations in both the bagasse and the fruiting bodies of mushrooms; and the bioaccumulation factor (BAF) in mushroom, for the heavy metals - Cadmium, Arsenic, Copper and Chromium were found to be 1.48, 1.22, 1.16 and 0.85 respectively. These results indicated biomagnification of metal ion concentration in the mushrooms up-taken from bagasse. These metals, in such high concentrations, are lethal and cause many diseases in humans and other animals. Based on this study, it appears that while bagasse is indeed a promising substrate for mushroom cultivation, the high concentrations of metal ions present in it can potentially introduce toxicity to the mushrooms grown on bagasse. Therefore, it is important to consider these factors when using bagasse as a substrate and find ways to mitigate or remove the metal ions to ensure successful and safe mushroom cultivation.