低O2高CO2贮藏环境对马铃薯块茎淀粉-糖代谢的影响

为明确低O₂高CO₂贮藏环境对马铃薯块茎淀粉-糖代谢的影响,本试验以大西洋马铃薯为试验材料,研究体积分数为5%O₂+2%CO₂(CA1)、5%O₂+4%CO₂(CA2)、5%O₂+6%CO₂(CA3)、5%O₂+8%CO₂(CA4)及5%O₂+10%CO₂(CA5)的气体环境对马铃薯在4℃贮藏期间块茎中糖类、淀粉及淀粉-糖代谢相关酶腺苷二磷酸葡萄糖焦磷酸化酶(AGPase)、尿苷二磷酸葡萄糖焦磷酸化酶(UGPase)、淀粉磷酸化酶(SP)及转化酶(INV)]活性的影响,并对块茎中还原糖含量的变化与淀粉-糖代谢相关因子进行相关性分析。结果表明,适宜的低O₂高CO₂贮藏环境可有效抑制淀粉含量、AGPase活性、UGPase活性的下降,并且能够抑制还原糖、蔗糖、果糖、葡萄糖含量及SP、INV活性的上升,CA1环境贮藏的马铃薯块茎在整个贮藏期间淀粉含量显著高于CK(P<0.05),还原糖、蔗糖、果糖及葡萄糖含量显著低于CK(P<0.05),AGPase、UGPase活性显著高于CK(P<0.05),而SP、INV活性均显著低于CK(P<0.05);相关性分析结果表明,还原糖含量与淀粉含量、AGPase活性、UGPase活性呈极显著负相关(P<0.01),与葡萄糖含量、果糖含量、SP活性及INV活性呈极显著正相关(P<0.01)。综上,马铃薯在CA1(5%O₂+2%CO₂)环境下贮藏可有效延缓块茎低温贮藏期间“糖化”现象的出现,AGPase、UGPase、SP、INV在贮藏过程中起到了一定的调控作用。本研究结果为加工型马铃薯的安全贮藏及明确“低温糖化”机理提供了理论依据。

Effects of Low Oxygen and High Carbon Dioxide Storage Environment on Starch-Glucose Metabolism of Potato Tubers

In order to clarify the effect of low O₂ and high CO₂ storage environment on starch-sugar metabolism of potato tubers, Atlantic potatoes were used as materials, and the effects of controlled atmosphere storage systems of 5% O₂+2% CO₂ (CA1), 5% O₂+4% CO₂ (CA2), 5% O₂+6% CO₂ (CA3), 5% O₂ + 8% CO₂ (CA4) and 5% O₂+10% CO₂ (CA5) on carbohydrate, starch content and starch sugar metabolism related enzymes AGPase, UGPase, SP, INV of potato tubers during storage at 4℃ were studied. The correlation between the content of reducing sugar in tubers and the factors related to starch-sugar metabolism was analyzed. The results showed that the suitable low O₂ and high CO₂ storage environment could effectively inhibit the decline of starch, AGPase, UGPase, and inhibit the increase of reducing sugar, sucrose, fructose, glucose content and SP, INV. During the whole storage period, the tubers starch content of CA1 was significantly higher than control group(CK) (P<0.05), and the contents of reducing sugar, sucrose, fructose and glucose were significantly lower than CK (P<0.05), the activity of AGPase, UGPase were significantly higher than CK (P<0.05), while the activities of SP and INV were significantly lower than CK (P<0.05). The correlation analysis results showed a great significant negative correlation between reducing sugar and starch, AGPase, UGPase (P<0.01), a very significant positive correlation between reducing sugar and glucose, fructose content, SP and INV (P<0.01). In conclusion, CA1 (5% O₂+2% CO₂) condition could effectively delayed the occurrence of ‘saccharification’ phenomenon of potato tubers during low temperature storage. AGPase, UGPase, SP and INV played a certain regulatory role in this process. The result could provide a theoretical basis for the safe storage of processed potatoes and clarify the mechanism of ‘low temperature saccharification’.