Chaudhari Sandeep A, Singhal Rekha S
Food Engineering and Technology Department, Institute of Chemical Technology, Matunga, Mumbai 400019, Maharashtra, India.
Food Engineering and Technology Department, Institute of Chemical Technology, Matunga, Mumbai 400019, Maharashtra, India.
Int J Biol Macromol. 2015 Aug;79:398-404. doi: 10.1016/j.ijbiomac.2015.05.006. Epub 2015 May 15.
Cutin a polymeric biological macromolecule made up of esterified polyacids which acts as an inducer of cutinase. The present work was based on screening and characterization of newer cutin source from the agro industrial wastes as inducers of cutinase production by Fusarium oxysporum MTCC 2480. Cutin isolated from peels of multi green colored watermelon (WMC) yielded 6.77 U/mL as compared to that 9.64 U/mL of cutinase using apple cutin. The FTIR and (13)C CP-MAS solid state NMR studies indicated the nature of WMC to be an aliphatic polyester of polyhydroxy fatty acids. A further FTIR spectroscopic study on dewaxed cutin confirmed that the ester linkages in WMC were completely hydrolyzed during submerged fermentation. GC-MS data clearly indicated the critical structural feature of WMC viz. hydroxyl groups at ω-position and middle of the fatty acid chain. The amorphous nature of WMC was confirmed by XRD. DSC of WMC showed two endothermic transition peaks, one broad appearing at 30-60 °C and other at 145 °C. Thermogravimetric analysis of WMC suggested it to be thermally stable up to 200 °C. This study warrants further work on using WMC as a substrate for fermentative production of cutinase.
角质是一种由酯化多元酸组成的聚合生物大分子，可作为角质酶的诱导剂。目前的工作基于从农业工业废弃物中筛选和表征新型角质源，作为尖孢镰刀菌MTCC 2480产生角质酶的诱导剂。从多绿色西瓜（WMC）果皮中分离得到的角质产生的角质酶为6.77 U/mL，而使用苹果角质产生的角质酶为9.64 U/mL。傅里叶变换红外光谱（FTIR）和（13）C交叉极化魔角旋转（CP-MAS）固态核磁共振研究表明，WMC的性质是多羟基脂肪酸的脂肪族聚酯。对脱蜡角质的进一步FTIR光谱研究证实，在深层发酵过程中，WMC中的酯键完全水解。气相色谱-质谱（GC-MS）数据清楚地表明了WMC的关键结构特征，即脂肪酸链的ω位和中间位置的羟基。X射线衍射（XRD）证实了WMC的无定形性质。WMC的差示扫描量热法（DSC）显示出两个吸热转变峰，一个宽峰出现在30-60°C，另一个出现在145°C。WMC的热重分析表明，它在200°C以下具有热稳定性。这项研究有必要进一步开展将WMC用作发酵生产角质酶底物的工作。
