Soil emendation with nano-fungal chitosan for heavy metals biosorption

The bioremediation of water and soil, from heavy metal (HM) contamination, is a continuing worldwide demand. Chitosan, as a promising bioactive polymer, was produced from grown fungal (Cunninghamella elegans) mycelia and had a molecular weight of 112 kDa and a deacetylation degree of 87%. Sodium tripolyphosphate was applied for the synthesis of chitosan nanoparticles (NCt) from fungal chitosan (Cts); the particle size of produced NCt was in range of 5–45 nm. The produced biopolymers were used for HM absorption, Pb2+ and Cu2+ at concentration range of 100–300 ppm, from aqueous solution and soil matrix. Both Cts and NCt had high adsorption capacity toward the examined HM, with higher affinity as adsorbents to Pb2+ than to adsorb Cu2+ from water or after amendment of soil matrix. The produced NCt particles were highly effective than bulk Cts for the remediation and biosorption of contaminant metals, Pb2+ and Cu2+. Both Cts and NCt could be effectually applied as amendments in HM-contaminated soils for their bioremediation.