School of Life and Health Sciences, Hainan University, Haikou, 570228, China.
School of Life and Health Sciences, Hainan University, Haikou, 570228, China.
Phytochemistry. 2024 Aug;224:114143. doi: 10.1016/j.phytochem.2024.114143. Epub 2024 May 17.
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 HO 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.
木薯（Manihot esculenta Crantz）是一种重要的全球性块茎作物，但在收获后会发生显著的生理劣变（PPD），从而导致巨大的经济损失。木薯的 PPD 现象与活性氧（ROS）的积累密切相关，而氨基酸在调节信号通路和清除 ROS 方面起着关键作用。本研究对 8 个木薯品种进行了贮藏性能研究。结果表明，在 8 个木薯品种中，SC5 品种的贮藏性能最好，而可食用的 SC9 品种的贮藏性能则较差。对 8 个木薯品种的游离氨基酸进行比较分析，发现脯氨酸、天冬氨酸、组氨酸、谷氨酸、苏氨酸和丝氨酸的含量发生了变化。在 SC9 中添加这 6 种氨基酸可以抑制 PPD。脯氨酸被确定为抑制 PPD 的关键氨基酸。用 5g/L 的最佳外源脯氨酸处理后，与未处理的木薯相比，劣变速率降低了 17.9%。HO 含量降低，过氧化氢酶、超氧化物歧化酶和抗坏血酸过氧化物酶活性增加。脯氨酸处理被证明是一种有效的方法，可以减轻细胞氧化损伤，抑制木薯 PPD，延长货架期。
