Changes in soluble sugars contribute to energy metabolism and membrane stability involved in cold acclimation of postharvest fruit. The aim of this study was to investigate the impacts of exogenous trehalose on soluble sugar and energy metabolisms in response to membrane stability and chilling injury (CI) of ‘Kim Ju’ guava fruit. Mature guava fruits were treated with 0 (control), 50, 100, 200 and 400 mM trehalose and stored at 8 °C for 14 d, followed by 4 d of shelf storage at 25 °C. Trehalose at 200 mM was the most effective in lowering CI while the fruit quality is still high. The trehalose-treated fruit exhibited a higher index of membrane stability and energy level accompanied by a rise in endogenous trehalose, sucrose, glucose 6-phosphate and fructose 6-phosphate levels but glucose and fructose levels were depressed. Moreover, trehalose treatment promoted the activities of sucrose synthetic enzyme including, sucrose phosphate synthase and sucrose synthase (synthesis) as well as trehalose hydrolytic enzyme such as trehalase and glycolytic enzymes including, hexokinase, fructokinase, phosphoglucoisomerase and pyruvate kinase. On the other hand, trehalose treatment reduced the activities of sucrose hydrolytic enzymes such as sucrose synthase (cleavage) and invertase. The increase in enzyme activities and soluble sugar levels by trehalose treatment improved the energy status and membrane stability during cold storage which inhibited CI development of guava fruit.

可溶性糖的变化有助于能量代谢和膜稳定性，涉及采后果实的冷驯化。本研究的目的是研究外源海藻糖对可溶性糖和能量代谢的影响，以响应'Kim Ju'番石榴果实的膜稳定性和冷害（CI）。成熟的番石榴果实用 0（对照）、50、100、200 和 400 mM 海藻糖处理并在 8 °C 下储存 14 天，然后在 25 °C 下货架储存 4 天。200 mM 的海藻糖在降低 CI 方面最有效，而果实质量仍然很高。海藻糖处理的果实表现出更高的膜稳定性指数和能量水平，伴随着内源海藻糖、蔗糖、葡萄糖6-磷酸和果糖6-磷酸水平的升高，但葡萄糖和果糖水平降低。而且，海藻糖处理促进了包括蔗糖磷酸合酶和蔗糖合酶（合成）在内的蔗糖合成酶以及海藻糖水解酶（例如海藻酶）和糖酵解酶（包括己糖激酶、果糖激酶、磷酸葡萄糖异构酶和丙酮酸激酶）的活性。另一方面，海藻糖处理降低了蔗糖水解酶如蔗糖合酶（裂解）和转化酶的活性。海藻糖处理后酶活性和可溶性糖水平的增加改善了冷藏期间的能量状态和膜稳定性，从而抑制了番石榴果实的CI发育。蔗糖磷酸合酶和蔗糖合酶（合成）以及海藻糖水解酶如海藻糖酶和糖酵解酶，包括己糖激酶、果糖激酶、磷酸葡萄糖异构酶和丙酮酸激酶。另一方面，海藻糖处理降低了蔗糖水解酶如蔗糖合酶（裂解）和转化酶的活性。海藻糖处理后酶活性和可溶性糖水平的增加改善了冷藏期间的能量状态和膜稳定性，从而抑制了番石榴果实的CI发育。蔗糖磷酸合酶和蔗糖合酶（合成）以及海藻糖水解酶如海藻糖酶和糖酵解酶，包括己糖激酶、果糖激酶、磷酸葡萄糖异构酶和丙酮酸激酶。另一方面，海藻糖处理降低了蔗糖水解酶如蔗糖合酶（裂解）和转化酶的活性。海藻糖处理后酶活性和可溶性糖水平的增加改善了冷藏期间的能量状态和膜稳定性，从而抑制了番石榴果实的CI发育。