Exploring Textile Dye from Microorganisms, an Eco-friendly Alternative

Aims: Being an ancient art, the concept of dyeing using natural resource is neither a noble issue. To develop a green and sustainable world, the natural resources are now common sought. In this study screening of pigment producing microorganisms and extraction of pigments were the prime concern.

Study Design: An environmental screening was performed to isolate pigmented microorganisms. Extractability of the pigments and dying capability of textiles were also evaluated.

Place and Duration of Study: Soil, water and air were sampled and cultured from different regions around Jessore, Bangladesh. Isolation and tests were performed at Jessore University of Science and Technology.

Methodology: Soil and water samples were inoculated on bacterial and fungal media. Media were exposed for 1h to air for air sampling. Pigmented isolates were cultured in bulk, dried and went through solvent extraction by ethanol and water. Soluble pigment producing isolates were identified and dying capability to cotton and silk were evaluated. Pigments were also tested for antimicrobial activity and allergic test to human skin to be used for medicated fabric.

Results: A few pigmented bacteria and several pigmented fungi were isolated. By solvent extraction, only two colors were extracted having greater solubility. The isolates were preliminarily identified as Aspergillus sp. and Penicillium sp., producing green and red color respectively. The dying capacity to cotton and silk fabrics were found satisfactory in respect to wash fastness. The extracted colors also showed antimicrobial activity against several pathogenic microorganisms. Pigments were also subjected to hypersensitivity test and found non allergic to human skin.

Conclusion: However, these dyes have the potentiality to be used in sophisticated garment for allergic patients to chemical dyes and infants. As the biomass yielding capability of pigmented fungi were very low in the designed media, further modification of media and growth conditions are to be optimized to maximize biomass and large-scale dye production.