The digestive system of a worm is capable of heavy metal ions detaching from aggregates between these ions and humic substances in the waste as it rots (Pattnaik and Reddy, 2012). In the process of enzymes activation the assimilation of metal ions is mediated by worms.In another research conducted by Turpeinen (2002) it is claimed that different bacteria, fungi, algae and actinomycetes are able to consume large amount of heavy metals. The researcher underlines a special ability of Chlorella, Anabaena inaequalis, Westiellopsis prolifica, Stigeoclonium tenue, Synechococcus sp. pacify heavy metals. Nevertheless it is always difficult to choose appropriate strategies for heavy metals extraction. Actually, the scientists of previous years were focused on biosorption (a combination of absorption and adsorption). There was a higher level of Cd++ and Ni++ I in comparison with laboratory cells. Fungi are able to absorb heavy metals by their cells too (Malik, 2004). Different types of cells are effective in a serious struggle against heavy metals presence in soil and water. Firstly, it is possible to remove heavy metals in accordance with the following mechanisms:(a) Independent accumulation of heavy metals in the process of metabolism. The positive charge of ions attracts negative charges of heavy metals. It is possible to illustrate this process by the following example: “Rhizopus arrhizus adsorption depends on ionic radius of Li3+, Mn2+, Cu2+, Zn2+, Cd2+, Ba2+, Hg2+ and Pb2+. However, binding of Hg2+, Ag2+, Cd2+, A13+, Ni2+, Cu2+ and Pb2+ strongly depends on concentration of yeast cells” (Jayabarath, Sundar, Arulmurugan, Giridhar, 2009).(b) Dependent accumulation of heavy metals in the process of metabolism. Heavy metal ions are transferred to cells basing on the cell membrane. Nevertheless, ions are precipitated around the cells, and are collected intracellularly as compared with metal-binding proteins. There are many external factors, which exert a serious influence on heavy metals absorption. These are: pH, anions, cations and organic materials etc (Environmental Biotechnology).Moreover, in another study microbial strains were isolated from the soil of metallurgical environment. In the result of heavy metals bioremediation 72 acidothermophilic autotrophic microbes were isolated obtained bioabsorption potentiality. Heavy metals were checked for their biosolubilization ability. Thus, it
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