Department of Microbiology, Shivaji University Kolhapur, 416004, India.
Department of Biochemistry, Shivaji University Kolhapur, 416004, India.
J Microbiol Methods. 2019 Apr;159:99-111. doi: 10.1016/j.mimet.2019.02.021. Epub 2019 Mar 2.
The present study is the first report of utilizing Tithonia rotundifolia weed as a substrate for inulinase production from Fusarium solani JALPK. It also deals with the statistical optimization of culture conditions to enhance the enzyme yield. Amongst the 11 variables screened by Plackett- Burman design, Inulin in combination with Agave sisalana extract, Tithonia rotundifolia extract and NaNO had a significant influence on inulinase production and their concentrations were further optimized employing Box Behnken design. An enhancement of inulinase production from 970 EU/mL to 3261.011 EU/mL was gained after media optimization. Amongst the screened carbon sources Tithonia rotundifolia was found to be very effective in stimulating elevated inulinase synthesis. The Tithonia rotundifolia weed extract was treated with inulinase from Fusarium solani JALPK to form fructose which was estimated spectrophotometrically. This liberated fructose was also confirmed by osazone formation test and FTIR. HPTLC analysis of product revealed the exoinulinase nature of the enzyme produced by Fusarium solani JALPK since fructose was the only end product after hydrolysis of inulin rich weed in fermented broth. Thus the elevated extracellular inulinase yielding novel property of Fusarium solani JALPK (KY914560) contributes in considering it as a potential candidate with food, pharmaceutical and bioremediation applications.
本研究首次报道了利用黄葵杂草作为尖孢镰刀菌 JALPK 菊粉酶生产的基质，并对其进行了统计优化以提高酶产量。在 Plackett-Burman 设计筛选的 11 个变量中，菊粉与龙舌兰麻提取物、黄葵提取物和 NaNO 对菊粉酶生产有显著影响，进一步采用 Box-Behnken 设计对其浓度进行了优化。经过培养基优化，菊粉酶产量从 970 EU/mL 提高到 3261.011 EU/mL。在所筛选的碳源中，黄葵被发现对提高菊粉酶合成非常有效。用尖孢镰刀菌 JALPK 的菊粉酶处理黄葵杂草提取物，形成果糖，然后通过分光光度法进行估计。通过糖脎形成试验和 FTIR 也证实了游离果糖的存在。产物的 HPTLC 分析表明，该酶具有外切菊粉酶性质，因为在发酵液中水解富含菊粉的杂草后，果糖是唯一的终产物。因此，尖孢镰刀菌 JALPK（KY914560）具有较高的细胞外菊粉酶产率，这一特性使其有望在食品、制药和生物修复等领域得到应用。
