High potential to decolorize the aqueous solution contain Direct violet 51 by the proteinaceous nanofibrils extracted from wastes

The expansion of worldwide different heavy and light industries has led to an equivalent expansion in the use of synthetic dyestuffs, resulting in a rise in environmental pollution. More than 70% the dyestuffs used by the industry are azo dyes, which are used thousands of tons per year in the textile, printing, food, papermaking and cosmetic industries. Azo dyes can affect the aquatic ecosystem, decreasing the light penetration and gas dissolution into lakes, rivers and other bodies of water. On the other hand, they and their chemical derivatives are indicated as mutagenesis agents. One way which has been widely used for removing dyes from wastewater is coagulation /flocculation method. Many proteins can convert to stable β-conformation structure called amyloid fibrils. In this study, the effect of crystalline-nanofibrils prepared from eye lens on removing Direct violet 51 as a high consumed azo dye from its aqueous solution was investigated. Fresh lens was cleaned in distilled water and then were homogenized. The crystalline proteins extracted from the homogenized, were incubated for 20 minutes in different temperatures and then kept in room temperature for more hours. ThT intensity and Congo red absorbance were employed to measure the fibrillation. The effects of such fibrils were evaluated on the decolorization of the aqueous solution of Direct violet 51. Results indicated that the protein nanofibrils which prepared from crystalline removed up to 98% the azo dye from its solution with formation of coagulated bodies during one day(with 10% w fibrils to dye). Such procedure might be economical and carried out easily and these bio-materials are very eco-friendly. Therefore they could be considered as a feasible method for omission of color wastewater from the earth. Of course these protein nanofibrils are now widely accepted as having potential for use in the field of bionanotechnology.