机构地区: 广州大学化学化工学院食品系
出 处: 《园艺学报》 2008年第10期1425-1430,共6页
摘 要: 以‘巴西’香蕉果实为试材,研究了果实采后在22℃和6℃下贮藏期间NAD激酶(NADK)活性、冷害发生情况、膜渗透性、丙二醛(MDA)含量、多酚氧化酶(PPO)以及苯丙氨酸解氨酶(PAL)活性变化。结果表明,6℃下贮藏3d时果实出现冷害症状,11d时冷害加重,同时NAD激酶活性、膜渗透性、MDA含量和PPO活性均始终高于22℃贮藏的,并在11d时达到高峰,而PAL活性则呈下降趋势,其活性始终低于22℃贮藏的。6℃下用NAD激酶激活剂氯化钙处理香蕉果实后,NADK受到激活,冷害程度加重,而用钙离子通道阻塞剂异博定(verapamil,Vp)处理后则抑制了NADK活性,果实冷害症状延迟4d出现,冷害程度减弱,说明香蕉果实冷害发生与NADK活性变化密切相关。 Changes of activity of NAD kinase, polyphenol oxidase (PPO) and phenylalanine ammonialyase (PAL), chilling injury and relative conductivity, MDA content of postharvest banana fruits storage at 22 and 6 ℃ were studied. The results showed that the fruits at 6 ℃ for three days occured visible chilling injury and became more serious for 11 days. The activity of NAD kinase at 6 ℃ was higher than that at 22 ℃ during storage. Higher relative conductivity, MDA content and PPO activity were observed at 6 ℃ than those at 22 ℃ and reached peak on the 11 th day. However, the PAL activity at 6℃ was lower than that at 22℃ during storage. Pretreatment with CaCl2 could enhance the activity of NAD kinase and increase chilling injury of banana fruits at 6 ℃, but pretreatment with verapamil (Vp) had reverse effect. The results suggested that the chilling injury of postharvest banana fruits was highly related to the change of NADK activity.