鲜切南瓜贮藏过程中生理变化的研究

Study on the physiological and biochemical changes of fresh-cut winter squash during storage

采用新鲜南瓜为实验材料,经切割处理后,将鲜切南瓜贮藏在5℃和10℃下。在贮藏过程中分析测定了鲜切南瓜乙烯释放量、颜色、失重率、PPO和POD酶活性、总酚和可溶性蛋白质含量等生理生化指标,并且分析了10℃下鲜切南瓜伤害部位细胞以及远离伤害部位细胞的有关酶活性的变化。结果发现,南瓜切割后产生了颜色发白、乙烯生成量增加、PPO和POD活性提高等显著的生理生化变化,总酚和可溶性蛋白质含量也发生了不同程度的变化。研究还表明,由于伤害刺激信号转导作用,鲜切南瓜不但在伤害部位细胞具有较高PPO、POD酶活性,而且远离伤害部位细胞酶活性也有一定程度的增加。实验结果认为,鲜切南瓜对伤害的生理反应是整体响应。

The changes in physio-biochemistry of fresh-cut winter squash were investigated during storage at 5℃ and 10℃. Color changes, ethylene production, weight loss, polyphenol oxidase （PPO） and peroxidase （POD） activity,total phenolic and soluble protein contents were determined.The relative enzymes in different cell layers from cutting site were also analyzed at 10℃.The results showed that the physiological and biochemical changes of the fresh-cut winter squash occurred significantly, including color blushing, decreasing in weight and increasing in ethylene production and the activity of PPO and POD.The changes in total phenolic and soluble protein contents were also found in varying degree. The results of research indicated that cutting wound not only induced the obvious increase in PPO and POD activities in the cutting surface,the relative higher enzymatic activities were also found in the distant cell tissue from cutting site. It suggested that the response of winter squash to the cutting damage was an overall reaction of fresh-cut winter squash.