香蕉果实抗性淀粉含量变化及其与其他类型淀粉相关性分析

【目的】研究香蕉果实抗性淀粉形成机理，为选育高抗性淀粉香蕉品种和调控抗性淀粉合成提供理论基础。【方法】以 ‘巴西’蕉（Musa acuminata L. AAA group cv. Brazilian）果肉为试材，对香蕉果实采前和采后抗性淀粉含量变化及其与其他类型淀粉相关关系进行分析。【结果】香蕉果实发育过程中，总淀粉、直链淀粉、支链淀粉及抗性淀粉含量整体呈上升趋势，后熟过程中各种淀粉含量逐渐下降；乙烯处理加速了总淀粉、直链淀粉和支链淀粉的降解，但抗性淀粉降解速度较自然后熟慢；1-MCP处理香蕉果实各种淀粉含量呈先增后降的单峰曲线变化。相关性分析表明：香蕉采前果实抗性淀粉合成与直链淀粉含量变化呈显著正相关，与总淀粉和支链淀粉含量变化不相关；1-MCP处理后，抗性淀粉含量变化与直链淀粉含量达到显著正相关水平，与总淀粉含量变化不相关。【结论】香蕉果实抗性淀粉形成与直链淀粉含量密切相关，在香蕉果实发育过程中可通过调控直链淀粉含量促进抗性淀粉合成。

Changes of Resistant Starch Content and Correlation with the other Types of Starch in Banana Fruit

【Objective】The research on resistant starch formation from banana fruit will provide a theoretical basis for practical schemes for breeding cultivars with high starch resistance and improving resistant starch content in banana fruit. 【Method】Banana (Musa acuminata L. AAA group cv. Brazilian) pulp was used to investigate the changes of resistant starch content and correlation with the other types of starch.【Result】The content of total starch, amylose, amylopectin, and resistant starch gradually increased in banana fruit during development, and decreased in banana fruit during postharvest. After treatment with ethylene, the degradation of total starch, amylose, and amylopectin was accelerated; however, the rate of resistant starch degradation was slower than that of the natural ripened (untreated). A single peak was observed for starch content of banana fruit after treatment with 1-methylcyclopropene (1-MCP). Correlation analysis showed that resistant starch formation had a positive correlation with the increase of amylose content. No correlation was found between amylopse and resistant starch content during the development, but resistant starch had a positive correlation with the amylose content; while it had no significant correlation with total starch content after treatment with 1-MCP.【Conclusion】The resistant starch formation is closely related to amylose content. Therefore, regulation of amylose content in banana fruit during the development might promote the formation of resistant starch.