Instituto de Procesos Biotecnológicos y Químicos (IPROByQ), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Departamento de Tecnología, Rosario, Argentina.
Instituto de Química de Rosario (IQUIR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Departamento de Química Analítica, Rosario, Argentina.
Prep Biochem Biotechnol. 2020;50(10):979-991. doi: 10.1080/10826068.2020.1777425. Epub 2020 Jun 18.
Xylanolytic enzymes were produced by NRRL3 grown on agro-industrial by-products obtained from the processing of wheat flour without pretreatment. Significant parameters for xylanase production were screened and optimized. The xylanolytic activity obtained in the optimized extract was 138.3 ± 2.6 U/mL, higher than the activity obtained in an unoptimized medium (14.5 ± 0.3 U/mL) in previous work. The optimized fermentation process was performed in a successful 40-fold scale-up. The optimized enzymatic extract obtained was characterized by LC-MS. Nine enzymes were identified as constituents of the xylanolytic complex. Moreover, the xylanolytic enzymes were stable until 60 °C and over a broad range of pH. Sodium, calcium, cobalt and manganese had no inhibitory effect, meanwhile 1% w/v polyvinylpyrrolidone and 1% w/v dextran increased the xylanolytic activity. The saccharification efficiency was evaluated and the surface morphology of the lignocellulosic substrate was monitored by using scanning electron microscopy (SEM). The synergistic combination of the extracted (o purified) xylanolytic enzymes permitted a higher xylan conversion beneficial for diverse applications, such as bioethanol production. Thus, these agroindustrial by-products can be used within the framework of a circular economy, rendering an added value bioproduct, which is reused in the industry.
木聚糖酶由 NRRL3 在未预处理的小麦粉加工得到的农业工业副产物上生长时产生。筛选和优化了木聚糖酶生产的重要参数。在优化的提取物中获得的木聚糖酶活性为 138.3±2.6 U/mL，高于以前工作中在未优化的培养基中获得的活性（14.5±0.3 U/mL）。成功进行了 40 倍放大的优化发酵工艺。对优化的酶提取物进行了 LC-MS 分析。鉴定出 9 种酶作为木聚糖酶复合物的组成部分。此外，木聚糖酶在 60°C 下和宽 pH 范围内稳定。钠离子、钙离子、钴离子和锰离子没有抑制作用，而 1%w/v 聚乙烯吡咯烷酮和 1%w/v 葡聚糖增加了木聚糖酶的活性。评价了糖化效率，并通过扫描电子显微镜（SEM）监测了木质纤维素基质的表面形态。提取（或纯化）的木聚糖酶的协同组合允许更高的木聚糖转化率，有利于各种应用，例如生物乙醇生产。因此，这些农业工业副产物可以在循环经济框架内使用，产生附加值的生物制品，在工业中再利用。
