Optimized physio-chemical conditions for improved xylanase production by Streptomyces sp. CSMPJR101 isolated from...

Xylanases are key industrial enzymes that catalyze the hydrolysis of xylan, a major component of plant hemicellulose, and are increasingly important for sustainable bioprocesses in sectors such as biofuels, pulp and paper, animal feed, and food processing. This study investigates the production of xylanase by Streptomyces sp. CSMPJR101, a potent xylanolytic strain isolated from lignocellulose-rich bamboo forest soils of Manjavadi Kanavai, Tamil Nadu, India. Among 162 morphologically distinct Streptomyces isolates, CSMPJR101 exhibited the highest xylanase activity, highlighting the biotechnological potential of bamboo forest microbiomes. Taxonomic characterization based on morphological, physiological, chemotaxonomic features, and 16S rRNA gene sequencing confirmed its affiliation with the genus Streptomyces, while species-level assignment remained unresolved. Key fermentation parameters influencing xylanase production were systematically evaluated and optimized, resulting in a maximum xylanase activity of 437.3 ± 5.3 U/mL under optimal conditions: 72 h incubation at 40 °C, pH 7.0, 50 mL working volume in a 250 mL flask, and 2% (v/v) inoculum size, with glucose or xylose as preferred carbon sources and meat or beef extract as organic nitrogen sources. Supplementation with thiamine (vitamin B1) and the non-ionic surfactant Tween 80 further enhanced enzyme production. The optimized process led to a substantial increase in xylanase yield compared to unoptimized conditions, underscoring the industrial potential of Streptomyces sp. CSMPJR101 for lignocellulosic biomass conversion and supporting its further evaluation in scale-up and applied bioprocessing studies.