草酸对采后蜂糖李果实品质和抗氧化代谢的影响

石其宇; 董晓庆; 黄世安; 朱守亮; 蔡明佳; 周亚; 龚钰

doi:10.13386/j.issn1002-0306.2020100201

草酸对采后蜂糖李果实品质和抗氧化代谢的影响

Effects of Oxalic Acid Treatment on Quality and Antioxidant Metabolism of Postharvest Fengtang Plum Fruit

摘要

摘要: 以蜂糖李果实为试材，经0 mmol/L（对照）以及0.5 mmol/L草酸（Oxalic acid，OA）处理10 min，晾干后贮藏于室温（25±1）℃下，通过测定果实品质、抗氧化物质含量以及抗氧化代谢相关酶活性的变化，研究草酸处理对蜂糖李果实保鲜效果的影响，并从抗氧化代谢角度解析其保鲜机制。结果表明：0.5 mmol/L草酸处理能够有效延缓蜂糖李果实失重率、腐烂率、呼吸速率的上升，推迟贮藏过程中果实呼吸高峰的到来，抑制果实固酸比、可溶性糖含量、丙二醛（Malondialdehyde，MDA）含量以及超氧阴离子（\rm O_2^-\cdot）水平的上升，同时能抑制蜂糖李果实硬度、可滴定酸（Titratable acid，TA）、叶绿素含量、维生素C（Vitamin C，V_C）含量、还原型谷胱甘肽（Glutathione，GSH）含量、抗坏血酸过氧化物酶（Ascorbate peroxidase，APX）活性、过氧化氢酶（Catalase，CAT）活性以及超氧化物歧化酶（Superoxide dismutase，SOD）活性的下降，并能将果实可溶性固形物含量（Soluble solides content，SSC）维持在较高的水平。但在试验中，草酸处理对蜂糖李果实可溶性蛋白含量以及过氧化物酶（Peroxidase，POD）活性的影响效果并不明显。通过对各项指标综合分析得出结论，0.5 mmol/L草酸处理能够延缓采后蜂糖李果实的成熟衰老进程，提升其抗氧化能力，抑制采后贮藏期间其果实品质的降低。

Abstract: In order to explore the effect of oxalic acid (OA) treatment on the preservation of fruit and analyzed the preservation mechanism from the perspective of antioxidant metabolism, Fengtang plum fruit was chosen as the experiment material, and treated with 0 mmol/L (control) and 0.5 mmol/L oxalic acid for 10 min, dried and stored at room temperature of (25±1) ℃, and the changes of fruit quality, antioxidant substance and activity of antioxidant metabolism-related enzyme were measured. The results showed that 0.5 mmol/L oxalic acid treatment effectively delayed the increase of weight loss rate, decay rate and respiration rate, delayed the arrival of fruit respiration peak during storage, inhibited the increase of solid-acid ratio, soluble sugar content, malondialdehyde (MDA) content and superoxide anion (\rm O_2^-\cdot ) level of Fengtang plum fruit, and also inhibited the decrease of fruit firmness, titratable acid (TA), chlorophyll content, vitamin C (V_C) content, glutathione (GSH) content, ascorbate peroxidase (APX) activity, catalase (CAT) activity and superoxide dismutase (SOD) activity decreased of Fengtang plum. At the same time, oxalic acid treatment maintained a high level of soluble solids content (SSC). However, the effect of oxalic acid treatment in the experiment on the soluble protein content and peroxidase (POD) activity was not obvious. Through a comprehensive analysis of various indicators, it is concluded that 0.5 mmol/L oxalic acid treatment can delay the ripening and senescence of Fengtang plum fruit after harvest, enhance its antioxidant capacity, and inhibit the fruit quality decreased during postharvest storage at room temperature.