摘要
研究了菠萝叶片中苹果酸、柠檬酸、草酰乙酸、α－酮戊二酸和草酸等有机酸和转氨酶、脱氢酶活性的昼夜变化。结果表明，除了草酸外，其他４种有机酸的含量都呈白天降低晚上增高的趋势。有机酸的含量在上午９∶００时有最高值，下午１８∶００时有最低值。苹果酸、柠檬酸、草酰乙酸、α－酮戊二酸和草酸的昼夜最大差值分别为１４０、６１、３１．８、８．２和６．７ｍｍｏｌ·ｋｇ－１ＦＷ。异柠檬酸脱氢酶和琥珀酸脱氢酶活性的昼夜变化与有机酸的趋势一致，白天降低晚上增高。可溶性蛋白和游离氨基酸含量以及谷草转氨酸、谷丙转氨酶活性在下午１８∶００时有最高值，凝胶电泳显示菠萝叶片中有新的蛋白带出现。
Day night changes of organic acids,transaminase and dehydragenase in pineapple leaves were studied.Leaves of pineapple collected at different diurnal intervals contained various amounts of malic acid,citric acid,oxaloacetic acid,α ketoglutaric acid and oxalic acid.Except the oxalic acid,all of the other four acid incresed at night,but decreased during daytime,being highest at 9∶00 A.M. and lowest at 18∶00 P.M.The maximum day night changes of malate (△ malate)、citrate (△citrate)、oxaloecetate (△oxaloacetate)、α ketoglutarate(△α ketoglutarate) and oxalate (△ oxalate) were 140、61、31.8、8.2 and 6.7 mmol·kg -1 FW,respectively.It resulted in the total △H + of 463 mmol·kg -1 FW.The day night changes of isocitrate dehydrogenase activities showed the same trend as day night changes of organic acids.The activities of glutamic oxaloacetic transaminase and glutamic pyruvic transaminase were higher during daytime than at night and had their peaks at 18∶00 P.M.There were two new protein bands in the protein electrophoresis scanning map at different time during a day.The results indicated that partial organic acids accumulated at night may come from Krebs Cycle and decrease of organic acids during daytime was relative to protein metabolism.
出处
《西北植物学报》
CAS
CSCD
1998年第4期538-544,共7页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金
关键词
菠萝叶片
有机酸
昼夜变化
脱氢酶
转氨酶
pineapple leaves,organic acids,day night changes,dehydrogenase,transaminase
