草酸对冷藏‘华优’猕猴桃果实木质化及相关酶活性的影响

研究了5 mmol·L~(-1)草酸溶液处理对采后‘华优’猕猴桃冷藏过程中木质化的调控。结果显示,草酸处理显著降低了果实冷藏期间木质素含量和总酚含量,显著抑制了木质素合成过程中重要酶——苯丙氨酸解氨酶(PAL)、4–香豆酸辅酶A连接酶(4-CL)、过氧化物酶(POD)以及多酚氧化酶(PPO)的活性。结合果实切面和石蜡切片,‘华优’果实木质素的积累主要发生在果肉组织和果心的维管束组织中;草酸能够有效减少低温下‘华优’猕猴桃果实木质素含量,这可能与其降低果实木质素合成关键酶的活性有关。

Effects of Oxalic Acid Treatment on Lignification and Related Enzymes Activities in ‘Huayou’ Kiwifruit During Cold Storage

The effects of 5 mmol · L-1 oxalic acid (OA) solution on kiwifruit (Actinidia chinensis ‘Huayou’) lignification in during cold storage were investigated.The results showed that,OA treatment significantly reduced lignin content and total phenolics content.Meanwhile,OA inhibited the key enzymes involved in the lignin biosynthesis,including phenylalanine ammonia-lyase (PAL,EC 4.1.3.5.),4-coumarate coenzyme A ligase (4-CL,EC 6.2.1.12.),peroxidase (POD,EC 1.11.1.7.) and polyphenol oxidase (PPO,EC 1.10.3.1.) activities.In addition,the research combined hand-cut samples and paraffin sections indicated that lignin accumulation of ‘Huayou’ kiwifruit mainly occurred in pulp tissue and vascular bundles;alleviation of fruit lignification via OA might be ascribed to subdued activities of the above four enzymes.