Vinasse Based Medium for Exoxylanase Production

Abstract

Vinasse is a liquid waste, produced during alcohol production was utilized for an isolate AA I bacterium to produce exoxylanase. Without any supplement as nutrients added, this isolate capable utilized remaining sugar and nitrogen from vinasse. An extracellular enzyme was released which qualitatively detected as xylanase when spot-platted on agar oat spelt xylan medium. The hydrolyzation ofxylan was indicated by clearance zone in medium, and further analysis by using TLC ofhydrolyzates showed that only xylose was produced. Suggested, this enzyme is exoxylanase which attacked xylan exowise from reducing end. The enzyme stable at a range pH 4.5-8.5 and temperature below 55°C with optimum activity at pH 5.5 and temperature 50"C. The exoxylanase with 72.7 KDa of molecular weight estimated by SOS-PAGE was achieved after ammonium sulfate precipitation followed by 2 steps purification using a size exclusive chromatography Sephadex GlOO and a weak anion exchanger DEAE Sepharose CL-68. No significant results when AAI grown at vinassc or using formulated medium containing 1% xylan, 0.5% pcpton and 0.25% malt extract. Using the same purification procedure, the yield of exoxylanase recovery were 46% and 4lS% when AA I cultivated at vinasse and formulated medium.