Zehra Mahwish, Syed Muhammad Noman, Sohail Muhammad
Department of Microbiology, University of Karachi , Karachi , Pakistan.
Department of Biochemistry, University of Karachi , Karachi , Pakistan.
Pol J Microbiol. 2020 Sep;69(1):19-26. doi: 10.33073/pjm-2020-002. Epub 2020 Jan 28.
Banana peels (BP), an under-utilized waste material, was studied for the production of xylanase and pectinase by MS16. The factors affecting the co-production of both the enzymes were separately studied for their influence under submerged (Smf) and solid-state fermentation (SSF) of BP. The strain was cultivated in the presence of mineral salt (MS) solution containing BP powder as a sole source of carbon and physical and nutritional factors varied to observe the change in the enzyme titers. The data revealed that the MS-based medium was appropriate for the production of both the enzymes; therefore, in subsequent experiments, the same medium was used. A temperature of 30-35°C was found better for the production of the two enzymes under Smf; however, the titers of pectinase dropped significantly at 40°C. Contrarily, xylanase production was inhibited at 40°C under SSF but not under Smf. Whereas, supplementation of xylan or pectin to BP induced the production of xylanase and pectinase, respectively. Lowering the pH value favored the production of both the enzymes under Smf; however, the production of pectinase improved significantly when a higher concentration of BP (1%) was used compared to the concentration (0.25%) required for the production of xylanase. Interestingly, the enzyme preparation obtained under SSF exhibited optimal activities of both the enzymes at higher temperatures when compared to those obtained under Smf. The data indicated that the physiology of the fungus differed greatly when the cultivation pattern varied from Smf to SSF and, hence, the enzymes produced were characteristically distinct. Banana peels (BP), an under-utilized waste material, was studied for the production of xylanase and pectinase by MS16. The factors affecting the co-production of both the enzymes were separately studied for their influence under submerged (Smf) and solid-state fermentation (SSF) of BP. The strain was cultivated in the presence of mineral salt (MS) solution containing BP powder as a sole source of carbon and physical and nutritional factors varied to observe the change in the enzyme titers. The data revealed that the MS-based medium was appropriate for the production of both the enzymes; therefore, in subsequent experiments, the same medium was used. A temperature of 30–35°C was found better for the production of the two enzymes under Smf; however, the titers of pectinase dropped significantly at 40°C. Contrarily, xylanase production was inhibited at 40°C under SSF but not under Smf. Whereas, supplementation of xylan or pectin to BP induced the production of xylanase and pectinase, respectively. Lowering the pH value favored the production of both the enzymes under Smf; however, the production of pectinase improved significantly when a higher concentration of BP (1%) was used compared to the concentration (0.25%) required for the production of xylanase. Interestingly, the enzyme preparation obtained under SSF exhibited optimal activities of both the enzymes at higher temperatures when compared to those obtained under Smf. The data indicated that the physiology of the fungus differed greatly when the cultivation pattern varied from Smf to SSF and, hence, the enzymes produced were characteristically distinct.
香蕉皮（BP）是一种未得到充分利用的废料，本研究利用MS16菌株生产木聚糖酶和果胶酶。分别研究了在香蕉皮的液体深层发酵（Smf）和固态发酵（SSF）条件下，影响这两种酶共同产生的因素。该菌株在含有香蕉皮粉末作为唯一碳源的矿物盐（MS）溶液中培养，并改变物理和营养因素以观察酶活性的变化。数据显示，基于MS的培养基适合这两种酶的生产；因此，在后续实验中使用了相同的培养基。发现在30-35°C的温度下，液体深层发酵更有利于这两种酶的产生；然而，在40°C时果胶酶的活性显著下降。相反，在固态发酵条件下，40°C时木聚糖酶的产生受到抑制，但在液体深层发酵条件下不受影响。此外，向香蕉皮中添加木聚糖或果胶分别诱导了木聚糖酶和果胶酶的产生。降低pH值有利于液体深层发酵条件下这两种酶的产生；然而，与生产木聚糖酶所需的浓度（0.25%）相比，使用较高浓度的香蕉皮（1%）时，果胶酶的产量显著提高。有趣的是，与液体深层发酵获得的酶制剂相比，固态发酵获得的酶制剂在较高温度下表现出两种酶的最佳活性。数据表明，当培养模式从液体深层发酵变为固态发酵时，真菌的生理特性有很大差异，因此产生的酶也具有明显的特征。香蕉皮（BP）是一种未得到充分利用的废料，本研究利用MS16菌株生产木聚糖酶和果胶酶。分别研究了在香蕉皮的液体深层发酵（Smf）和固态发酵（SSF）条件下，影响这两种酶共同产生的因素。该菌株在含有香蕉皮粉末作为唯一碳源的矿物盐（MS）溶液中培养，并改变物理和营养因素以观察酶活性的变化。数据显示，基于MS的培养基适合这两种酶的生产；因此，在后续实验中使用了相同的培养基。发现在30–35°C的温度下，液体深层发酵更有利于这两种酶的产生；然而，在40°C时果胶酶的活性显著下降。相反，在固态发酵条件下，40°C时木聚糖酶的产生受到抑制，但在液体深层发酵条件下不受影响。此外，向香蕉皮中添加木聚糖或果胶分别诱导了木聚糖酶和果胶酶的产生。降低pH值有利于液体深层发酵条件下这两种酶的产生；然而，与生产木聚糖酶所需的浓度（0.25%）相比，使用较高浓度的香蕉皮（1%）时，果胶酶的产量显著提高。有趣的是，与液体深层发酵获得的酶制剂相比，固态发酵获得的酶制剂在较高温度下表现出两种酶的最佳活性。数据表明，当培养模式从液体深层发酵变为固态发酵时，真菌的生理特性有很大差异，因此产生的酶也具有明显的特征。
