Statistical Optimization, Partial Purification, and Characterization of Phytase Produced from Talaromyces purpureogenus NSA20 Using Potato Peel Waste and its Application in Dyes De-colorization

In this study, Talaromyces purpureogenus NSA20 as phytase-producing marine fungus was isolated and identified morphologically and genetically and deposited in Gene Bank with accession number MW031769.1. One factor at a time (OFAT) optimization was performed, where the result revealed that potato peel waste (1.5%) as a substrate was the highest for phytase production at 6 days, where the maximum activity of phytase was 138.4 U/ml. Moreover, Box–Behnken design as response surface methodology was carried out for statistical optimization of phytase production by T. purpureogenus NSA20. Statistical optimization illustrated that the optimized medium for phytase production increased 1.57 fold compared to the OFAT optimized medium. Partial purification of phytase was carried out, where the enzyme after precipitation with ammonium sulfate (80%) was 2.6-fold purified phytase, and the yield was 39.8 %., the specific activity was 31.19 U/mg proteins. Additionally, partially purified phytase was characterized; the maximum activity of phytase at Fe++ 0.1% and pH 5.5 at 37 oC was 350 U/ml. Eventually, phytase was applied for crystal violet and methyl red decolorization, where decolorization percentages of crystal violet and methyl red were 85.5% and 75% at 120 min, respectively.