Abstract：
Cassava (Manihot esculenta Crantz), a crucial global tuber crop, encounters significant economic losses attributed to postharvest physiological deterioration (PPD). The PPD phenomenon in cassava is closely related to the accumulation of reactive oxygen species (ROS), and amino acids play a pivotal role in regulating signaling pathways and eliminating ROS. In this study, the storage performance of eight cassava varieties were conducted. Cassava cultivar SC5 showed the best storage performance among the eight cassava varieties, but the edible cassava cultivar SC9 performed much worse. Comparative analysis of free amino acids was conducted in eight cassava varieties, revealing changes in proline, aspartic acid, histidine, glutamic acid, threonine, and serine. Exogenous supplementation of these six amino acids was performed to inhibit PPD of SC9. Proline was confirmed as the key amino acid for inhibiting PPD. Treatment with optimal exogenous proline of 5 g/L resulted in a 17.9% decrease in the deterioration rate compared to untreated cassava. Accompanied by a decrease in H2O2 content and an increase in catalase, superoxide dismutase and ascorbate peroxidase activity. Proline treatment proved to be an effective approach to alleviate cell oxidative damage, inhibit PPD in cassava, and prolong shelf life.
摘要：
木薯（ManihotesculentaCrantz），一种重要的全球块茎作物，遭遇归因于采后生理恶化(PPD)的重大经济损失。木薯中的PPD现象与活性氧（ROS）的积累密切相关，和氨基酸在调节信号通路和消除ROS中起关键作用。在这项研究中,对8个木薯品种的贮藏性能进行了研究。木薯品种SC5在8个木薯品种中表现出最佳的贮藏性能，但是食用木薯品种SC9的表现要差得多。对8个木薯品种的游离氨基酸进行了比较分析,揭示脯氨酸的变化，天冬氨酸,组氨酸,谷氨酸，苏氨酸,和丝氨酸。进行这6种氨基酸的外源补充以抑制SC9的PPD。脯氨酸被证实为抑制PPD的关键氨基酸。与未处理的木薯相比，用5g/L的最佳外源脯氨酸处理导致变质率降低17.9％。伴随着H2O2含量的减少和过氧化氢酶的增加，超氧化物歧化酶和抗坏血酸过氧化物酶活性。脯氨酸治疗被证明是缓解细胞氧化损伤的有效方法，抑制木薯中的PPD，延长保质期。
