Zhu Zhu-Jun, Chen Hai-Min, Chen Juan-Juan, Yang Rui, Yan Xiao-Jun
Key Laboratory of Marine Biotechnology of Zhejiang Province, Ningbo University , Ningbo, Zhejiang 315211, China.
Ningbo Institute of Oceanography , Ningbo, Zhejiang 315832, China.
J Agric Food Chem. 2018 Feb 7;66(5):1233-1241. doi: 10.1021/acs.jafc.7b05341. Epub 2018 Jan 24.
The multifunctional lipoxygenase PhLOX cloned from Pyropia haitanensis was expressed in Escherichia coli with 24.4 mg·L yield. PhLOX could catalyze the one-step bioconversion of C18-C22 fatty acids into C8-C9 volatile organic compounds (VOCs), displaying higher catalytic efficiency for eicosenoic and docosenoic acids than for octadecenoic acids. C20:5 was the most suitable substrate among the tested fatty acids. The C8-C9 VOCs were generated in good yields from fatty acids, e.g., 2E-nonenal from C20:4, and 2E,6Z-nonadienal from C20:5. Hydrolyzed oils were also tested as substrates. The reactions mainly generated 2E,4E-pentadienal, 2E-octenal, and 2E,4E-octadienal from hydrolyzed sunflower seed oil, corn oil, and fish oil, respectively. PhLOX showed good stability after storage at 4 °C for 2 weeks and broad tolerance to pH and temperature. These desirable properties of PhLOX make it a promising novel biocatalyst for the industrial production of volatile aroma compounds.
从坛紫菜中克隆的多功能脂氧合酶PhLOX在大肠杆菌中表达，产量为24.4 mg·L。PhLOX可以催化C18 - C22脂肪酸一步生物转化为C8 - C9挥发性有机化合物（VOCs），对二十碳烯酸和二十二碳烯酸的催化效率高于十八碳烯酸。在测试的脂肪酸中，C20:5是最合适的底物。脂肪酸能高产率生成C8 - C9 VOCs，例如，C20:4生成2E - 壬烯醛，C20:5生成2E,6Z - 壬二烯醛。水解油也作为底物进行了测试。这些反应分别从水解的向日葵籽油、玉米油和鱼油中主要生成2E,4E - 戊二烯醛、2E - 辛烯醛和2E,4E - 辛二烯醛。PhLOX在4℃储存2周后显示出良好的稳定性，并且对pH和温度具有广泛的耐受性。PhLOX的这些理想特性使其成为工业生产挥发性香气化合物的一种有前景的新型生物催化剂。
