摘要
香蕉果实采收后果肉中腐胺(PUT)含量随贮放时间的延长而逐渐下降,在果实出现乙烯高峰后又明显增加。果实采后初期亚精胺(SPD)、精胺(SPM)含量逐渐增加,果实出现乙烯高峰后,精胺明显积累,但亚精胺的变化较小。果皮中精胺的变化与果肉中的相似,但腐胺、亚精胺的变化则不同。精氨酸脱羧酶(ADC)和鸟氨酸脱羧酶(ODC)在果实采后初期活性较高,果实明显衰老时活性迅速降低。果肉中S—腺苷甲硫氨酸脱羧酶(SAMDC)活性先有增加,然后下降;而果皮中SAMDC则呈下降趋势。1——氨基环丙烷—1—羧酸合成酶(ACCS)变化与SAMDC不同,酶活性最高值较乙烯高峰提前二天到达。S—腺苷甲硫氨酸(SAM)在乙烯高峰出现时含量明显下降。结果认为,多胺对果实后熟、衰老的调节机理不但与竞争SAM有关,还与代谢平衡有关。
Putrescine (PUT) in pulp of banana fruits decreased gradually after harvest, then increased obviously after ethylene peak, whereas spermidine (SPD)and spermine (SPM) increased gradually at the early stage of post harvest, and after ethylene peak SPM accumulated significantly but SPD changed a little. SPD change of peel was similar to that of pulp while PUT and SPD were different.Arginine decarboxylase (ADC) and ornithine decarboxylase (ODC) had high activities at the early post harvest stage, but decreased rapidly when fruits showed obvious senescence. S-adenosylmethionine decarboxylase (SAMDC) activity of pulp increased and then decreased while SAMDC of peel decreased. Unlike SAMDC, 1-ami-nocyclopropane-1-carboxylic acid synthetase (ACCS)activities of pulp and peel reached maximums two days before ethylene peak. S-adenosylmethionine (SAM) content decreased significantly when ethylene peak occurred. It was suggested that regulation of polyamines on the ripening and senescene of banana fruits could be related to the competition for SAM and metabolic balance as well.
出处
《热带作物学报》
CSCD
1993年第2期87-92,共6页
Chinese Journal of Tropical Crops