The successful use of microorganisms in dying the fabrics proved that the bioproduction of textile colorants by fungi and bacteria can be an alternative way of large scale colorant production.;A new isolated marine bacterium similar to category of bacteria Vibrio gazogenes produces one main and two minor red colorants. LC/MS, GC/MS and NMR analysis revealed that colorants had molecular masses of m/z323.2096, 351.2303 and 321.1833 Da which is adequately matched (with less than 1PPM error) to the formula of C20H25N3O, C 22H29N3O and C20H23N 3O with maximum UV-Vis absorbance of 534.0, 534.7 and 537.0 nm respectively.;In order to increase the yield and produce new pigments, genetic modification was carried out on the bacteria using nitrosoguanidine as a mutation agent. The analysis of the mutated samples showed that two new main colorants C4 (C18H21N3O, m/z295.2, lambdamax: 533.7nm) and C5 (C19H23N3O, m/z309.2, lambda max: 502.0 nm) were produced. In addition to new pigments production, one mutated bacteria strain increased the yield by about 81% and another one produced a single colorant (prodigiosin) in 97% purity.;The colorants could dye acrylic, wool, nylon and silk fabric as a cationic dye and in addition provided antibacterial properties against gram negative bacteria E. coli and gram positive bacteria S. aureus . Due to their small molecular size, non-polar characteristic and heat stability, they can be used as disperse dye as well.;EPR test showed that they were able to produce free radicals with stability of more than one hour after the UV irradiation. LC/MS analyses confirmed the formation of photo products. The mechanism of the action of the antibacterial pigment on dyed fabric was assumed to be related to the photo-oxidation process.;In category of fungi, three species of fungus Fusarium Culmorum, 195a, 195b and GL34 were selected based on their ability to produce colorants while growing in potato dextrose agar (PDA) media. The colorant could dye wool, silk and nylon under acidic conditions and showed that they have characteristics similar to acid and disperse dyes.;UV-Vis, FTIR, LC/MS and GC/MS results confirmed that different species produced two main components with molecular masses of 594 and 570 Da at different ratio. The colorant with molecular mass of 570 was identified as aurofusarin (C30H18O12) a naphthoquinone pigment. The final identification of the major component with molecular mass of 593Da needs further spectroscopic investigations.
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