atural dyes are environmentally friendly and their benefits, including no need for petroleum resources, have led to a revival of demand for these dyes. One of the methods that has received much attention recently is the production of natural dyes from microbial resources. However, due to the cost of production of these dyes, it is necessary to optimize the production condition including nutrition and environmental conditions so that in addition to increasing the production efficiency of these dyes, the production cost is also affordable. In this study, considering the benefits of natural dyes as well as the widespread use of fluorescent dyes in different industries, Pseudomonas aeruginosa bacteria was used to produce fluorescent dye “pyoverdine”. In the first step, the bacterial culture medium was optimized to produce dye and increase the yield of production. For this purpose, various carbon sources including succinic acid, glucose and glycerol were investigated and finally succinic acid was selected as the optimal carbon source for the base culture for dye production. For this purpose, various carbon sources including succinic acid, glucose and glycerol were investigated and finally succinic acid was selected as the optimal carbon source for the base culture medium. Due to the structure and mechanism of metabolite production, the effects of metal salts such as copper sulfate, manganese sulfate and zinc sulfate as well as different amino acids cysteine, serine, glutamine and tyrosine in the culture medium were investigated. Considering the suitability of salts of zinc sulfate and serine amino acid, different concentrations (10, 50, 100, 150 ?M and 0.05, 0.1, 0.2, 0.4%) of these substances were also used in culture medium tested. According to the results of this study, the optimal value of 50 ?M concentrations of zinc sulfate and 0.1% serine amino acid increased dye production efficiency by 53% and 11% respectively. In the next step, the effect of environmental factors such as temperature (29, 37, 42 ?), pH (6, 7, 8, 9) and light on dye production efficiency was investigated and temperature 29 ?, pH = 6, and lighting conditions as optimal conditions were selected. Bacterial growth pattern and rate of dye production were plotted at optimum conditions and pyoverdine production was reached to maximum (460 mg / l) after 40 hours at stationary phase. FT-IR and HPLC analysis were done to investigate the chemical structural changes of dye and result confirmed that amino acid usage in culture medium can result in production of pyoverdine with different structures. Also, observation of the dye emission spectra extracted dye from media containing zinc sulfate and serine showed that despite no change the maximum emission wavelength, the presence of serine amino acid in the culture medium increased the fluorescence intensity of pyoverdine. In addition, the effect of temperature and pH on the dye extracted using FT-IR and absorbance assays showed the negative effect of high temperature on the dye structure and the change of its maximum wavelength absorbance at different pH. Finally, the possibility of using the extracted dye in pH-sensitive wound dressings was investigated and it was observed that the rate of absorbance of the dye released in the alkaline to acidic medium increased. This result showed the possibility of use of fluorescent dye in wound dressing system as an infection indicator. Also due to the similarity of the dye structure extracted with syntann, this dye was used as a mordant on cotton fabric to enhance the affinity of the methylene blue dye on the fabric which in addition to increasing the dye absorption, Washing and light fastness were also improved by 1 and 2 degrees, respectively.