摘要
【目的】研究增强UV-B辐射下台农一号芒果果肉抗氧化还原性成分的响应机理,为全球气候变化下芒果生产提供理论参考。【方法】以自然光照射为对照,设人工模拟增强UV-B辐射,强度为96 k J/(m^(2)·d)处理。2021年花后30 d(12月18日)至花后90 d(2022年2月17日)、2022年花后40 d(12月1日)至花后90 d(2023年1月21日),每隔10 d取芒果果肉样本1次,分别取样共7和6次。在果肉中测定各采样时期的总黄酮、总酚、超氧阴离子、过氧化氢(H_(2)O_(2))和丙二醛(MDA)含量,以及苯丙氨酸解氨酶(PAL)和多酚氧化酶(PPO)酶活性、相对电导率(REC)的动态变化。【结果】经增强UV-B辐射处理后,第1和2年活性氧(ROS)中超氧阴离子含量随时间的增加均呈逐渐升高趋势,超氧阴离子在第1年花后90 d、翌年花后70~90 d,辐射处理显著高于对照(P<0.05,下同);辐射处理的H_(2)O_(2)变化趋势则为第1年先下降后上升,仅花后90 d辐射处理显著高于对照,翌年总体上下降,花后70~90 d辐射处理均显著高于对照。芒果果肉中总酚和总黄酮含量2年动态变化均整体呈下降趋势,总酚在第1年花后50 d、翌年花后50和60 d,辐射处理显著高于对照;总黄酮在第1年花后40和50 d、翌年花后50和60 d,辐射处理显著高于对照。MDA含量和REC的2年变化趋势均为下降后上升,其中MDA含量在第1年花后40 d、翌年花后50 d,对照显著高于辐射处理,而2年在花后90 d MDA含量和REC均表现为辐射处理显著高于对照。芒果果肉辐射处理的PAL活性在第1年呈下降—上升—下降的变化趋势,花后40 d辐射处理显著高于对照,花后90 d时无显著差异;翌年呈上升—下降—上升的变化趋势,辐射处理50~70 d均表现为显著差异。PPO活性2年测定中的动态变化均呈先降后升的变化趋势,第1年在辐射处理40、60、70和80 d PPO活性显著高于对照,翌年花后60和90 d辐射处理显著高于对照。【结论】增强UV-B辐射处理下的芒果主要通过调节PAL活性来控制合成以黄酮为主的酚类化合物,并作为应对UV-B辐射的高效抗氧化剂。
【Objective】The purpose of the study was to investigate the response mechanism of antioxidant reduction components of Tainong No.1 mango pulp under strong UV-B radiation,so as to provide a theoretical reference for mango production under global climate change.【Method】Natural light irradiation was used as the control,and the artificial simulation enhanced UV-B radiation with an intensity of 96 kJ/(m^(2)·d)was set up.In 2021,mango pulp samples were taken every 10 d from 30 d after anthesis(December 18)to 90 d after anthesis(February 17,2022)and from 40 d after anthesis(December 1)in 2022 to 90 d after anthesis(January 21,2023),for a total of 7 and 6 samples,respectively.The con‐tents of total flavonoids,total phenols,superoxide anion hydrogen peroxide(H_(2)O_(2))and malondialdehyde(MDA),as well as the dynamic changes of phenylalanine ammonia-lyase(PAL)and polyphenol oxidase(PPO)enzyme activities and relative electrical conductivity(REC)were measured in the pulp at each sampling period.【Result】After enhanced UV-B radiation treatment,the content of superoxide anion in reactive oxygen species(ROS)of the first year and the second year increased gradually with the increase of time,and superoxide anion at 90 d after the first year and 70 to 90 d after the next year was significantly higher than that of control(P<0.05,the same below).The variation trend of H_(2)O_(2)under radiation treatment was firstly decreased and then increased in the first year,and only the radiation treatment at 90 d after anthesis was significantly higher than the control,H_(2)O_(2)in the next year decreased,and the radiation treatment at 70 to 90 d after anthesis was significantly higher than the control.The contents of total phenol and total flavone in mango pulp showed a decreasing trend at 2 years.The contents of total phenol at 50 d after anthesis in the first year and 50 and 60 d after anthesis in the next year were significantly higher than those of control under radiation treatment.The 2-year change trend of MDA content and REC was decreased and then increased.MDA content in the first year was significantly higher than that in the control group at 40 d after anthesis and 50 d after anthesis in the next year,while MDA content and REC were significantly higher than that in the control group at 90 d after anthesis.The PAL activity of mango pulp treated with radiation showed a trend of decreasing,increasing and decreasing at the first year.The PAL activity of mango pulp treated with radiation was significantly higher than that of control at 40 d after anthesis,and there was no significant difference at 90 d after anthesis.In the next year,there was an upward-downward-upward trend,and there were significant differences between 50-70 d after radiation treatment.The dynamic changes of PPO activity at 2 years showed a trend of first decreasing and then increasing.In the first year,the activity of PPO at 40,60,70 and 80 d was significantly higher than that of the control,and in the next year,the activity of PPO at 60 and 90 d after anthesis was significantly higher than that of the control.【Conclusion】Mango treated with enhanced UV-B radiation mainly control the synthesis of phenolic compounds dominated dominated by flavonoids through regulating PAL activity and act as efficient antioxidants against UV-B radiation.
作者
税贤
陈甜甜
彭俊杰
杜婧加
周开兵
SHUI Xian;CHEN Tian-tian;PENG Jun-jie;DU Jing-jia;ZHOU Kai-bing(Sanya Nanfan Research Institute,Hainan University,Sanya,Hainan 572025,China;Key Laboratory for Quality Regulation of Tropical Horticultural Plants of Hainan Province,College of Tropical Agriculture and Forestry,Hainan University,Haikou,Hainan 570228,China)
出处
《南方农业学报》
CAS
CSCD
北大核心
2024年第3期846-854,共9页
Journal of Southern Agriculture
基金
国家自然科学基金项目(32160677)。
