The Effects of Different Storage Temperatures on Lignification and Related Enzymes Activities in Loquat Pulp

The effects of different storage temperatures on lignification and related enzyme activities of loquat(Eriobotrya japonica Lindl.cv.Jiefangzhong) pulp stored at 4℃ and 12℃ were studied. The results showed that phenylalanine ammonia lyase(PAL,EC 4.1.3.5.) activity, 4-coumarate coenzyme A ligase(4-CL,EC 6.2.1.12.) activity,cinnamyl alcohol dehydrogenase(CAD,EC 1.1.1.195.) activity and peroxidase(POD,EC 1.11.1.7.) activity of loquat pulp stored at 4℃ were higher than those stored at 12℃,while polyphenol oxidase(PPO,EC 1.10.3.2.) activity was lower.The firmness and lignin content of loquat pulp at 4℃ increased during storage,which results in comparatively serious lignification in loquat pulp.The firmness and lignin content of loquat pulp at 12℃ were lower than at 4℃,hence a lo-wer level of lignification in loquat pulp.The main factor for lignification in loquat pulp is that the low temperature caused higher phenylalanine ammonia lyase activity and peroxidase activity.