Abstract:
Various synthetic colouring agents have the potential of carcinogenicity and/or teratoge extracted from fruits, vegetables, seed roots and microorganisms and often called “biocolours” due to their biological origin have proved to be safe and edible colouring agents. The microfungi Fusarium oxysporum f.sp. phaseolicola and Hormoconis resinae f.sp. avellaneumwere isolated from soil samples collected on plots under the bean crop and aviation gasoline respectively. Pure colonies were obtained and cultured in Potato Dextrose Broth (PDB) and Czapek Dox Broth (CDB) at pH between 1 and 14 and temperature between 20°C and 35°C. Considerable pigmentation was observed at a temperature of 30°C and at pH between 5 and 14, with the maximum yield at pH 7 and 30°C. Potato Dextrose Broth inoculated with Fusarium oxysporum f.sp. phaseolicola produced three pigments from viz: violet, purple and pink pigments whilst Czapek dox Broth produced a pastel yellow pigment. Both PDB and CDB inoculated with Hormoconis resinae f.sp. avellaneumproduced a dark brown pigment. All the pigments produced by the microfungi firmly dyed cellulose-based fabrics.
