表皮蜡质及其与果实贮藏关系的研究进展

表皮蜡质覆盖在水果表皮细胞的最外层,是一种疏水性物质。它在植物果实的生长、发育和贮藏中起着重要作用。表皮蜡质主要由超长链脂肪酸(very long chain fatty acids, VLCFAs)及其衍生物组成,它们的衍生物包括醛、烷烃、酯、伯醇、仲醇、酮和三萜类化合物。这种复杂的脂质混合物可能是在大多数植物的表皮细胞中生物合成的,并渗出到表面。表皮蜡不仅能使水果不易受到微生物的感染,而且还能减少对水果的机械损伤,从而保持了水果的商业价值。迄今为止,很多研究主要集中在果实采收前蜡质的变化、功能和调控上,而忽略了果实贮藏过程中蜡质的变化和功能。因此,本文对水果表皮蜡的化学组分、结构及其合成调控进行简单概述,重点阐述了表皮蜡质对果实采后品质的影响,包括水分损失、果实软化、生理失调和抗病害。研究表皮蜡质的合成机制来减少果实采后损失,并对表皮蜡质的研究前景进行了展望,为延长果实采后货架期和提高抗病性,研究新的优良品种提供理论参考。

Research progress on epicuticular wax and its relationship with fruit storage

Epidermal wax is a hydrophobic substance that covers the outermost layers of the fruit epidermal cells. It plays an important role in the growth, development and storage of plant fruits. Epidermal wax is mainly composed of very long chain fatty acids (VLCFAs) and their derivatives, including aldehydes, alkanes, esters, primary alcohols, secondary alcohols, ketones and triterpenoids. This complex lipid mixture may be biosynthesized in epidermal cells of most plants and seep to the surface. Epidermal wax not only makes fruits less susceptible to microbial infection, but also reduces the mechanical damage to fruits, thus maintaining the commercial value of fruits. Up to now, the research mainly focuses on the change, function and regulation of wax before fruit harvesting, but ignores the change and function of wax during fruit storage. Therefore, this paper briefly summarized the chemical composition, structure and synthetic regulation of fruit cuticular wax, with emphasis on the effects of cuticular wax on fruit postharvest quality, including water loss, fruit softening, physiological imbalance and disease resistance. This paper studied the synthetic mechanism of epidermal wax, and prospected the research prospect of cuticular wax to reduce postharvest loss of fruits and provide theoretical reference for prolonging postharvest shelf life of fruits, improving disease resistance and studying new fine varieties.