板栗贮藏期坚果腐烂机理的研究

Mechanism of Chestnut Rotting During Storage

研究了板栗室温和低温贮藏下 ,坚果呼吸强度、呼吸代谢途径及其关键性酶活性、代谢产物、膜脂过氧化与腐烂的关系。结果表明 :板栗室温贮藏呼吸强度呈下降趋势 ,无呼吸跃变峰。冷藏初期 (入贮 10d) ,低温显著抑制坚果呼吸强度 ,但冷藏中后期 (入贮 10d后 ) ,其低温抑制作用逐渐解除。低温显著抑制了糖酵解 ,并维持较高水平的三羧酸循环 ,阻止丙酮酸进入发酵 ,减少乙醇等有害物质产生和累积。低温抑制了Cat、POD活性 ,保持较高的SOD活性 ,延缓膜脂过氧化 ,降低坚果腐烂率。提出了板栗贮藏期坚果腐烂首先是生理伤害 ,其次才是病菌侵染的观点。

In this study, the relationship of respiration rate, metabolic pathway, key enzymatic activities, metabolites and membrane peroxidation with chestnut ( Castanea mollissima Bl) rotting during storage at room temperature and cold conditions were investigated. The results showed that respiration rate of chestnut gradually decreased during storage at room temperature, low temperature significantly inhibited the respiration rate during the first period (between 10 days) of the cold storage, then the inhibitory action would gradually release. Compared with room temperature, the lower temperature also obviously inhibited glycolysis, maintained higher level of TCA cycling and reduced conversion of pyruvate to ethanol and lactate. In addition, CAT and POD activities were inhibited while SOD activity were kept high under the lower temperature ,which resulted in reduction of membrane peroxidation. Subsequently, the chestnut rotting rate was significantly reduced. In conclusion, the primary reason for chestnut rotting is the reduction of proper physiologic function and then bacteria and pathogen infection.