Nan Xiang,Xiaoxiao Chang,Liuwei Qin,Kun Li,Siyun Wang,Xinbo Guo
In the present study, three matured Japanese plum cultivars with different colored peel and flesh were selected to mine the key transcription factors regulating anthocyanin formation in tissues. Results showed that PsMYB10 was correlated with structural genes C4H , F3H , and ANS . PsMYB6 could positively regulate C4H (r = 0.732) and accumulated anthocyanin in Sanhua plum’s flesh. Sanhua plum has the highest phenolic and anthocyanin contents (10.24 gallic acid equivalent mg·g −1 dry weight (DW) and 68.95 μg·g −1 DW), resulting itself superior biological activity as 367.1±42.9 Trolox equivalent mg·g −1 DW in oxygen radical absorbance capacity value and 72.79±4.34 quercetin equivalent mg·g -1 DW in cellular antioxidant activity value. The present work provides new insights into the regulatory mechanism of tissue-specific anthocyanin biosynthesis, confirming the pivotal role of anthocyanins in the biological activity of plums, providing essential support for the development of horticultural products enriched with anthocyanins.
The cuticle layer covering on surface plays important roles in the quality changes including visual of appearance, texture, and water loss for fruit. The surface microstructures, chemical composition of epi- and intracuticular waxes, and cutin monomers, as well as their effects on fruit transpiration in Sanhua plum were comprehensively carried out. Microscopic observation revealed an irregular surface morphology characterized by continuous crusts interspersed with sparsely distributed nano-granular crystals. Chemical analysis demonstrated that the epicuticular waxes were primarily composed of very-long-chain n -alkanes, secondary alcohols, aldehydes, fatty acids, primary alcohols, and alkyl esters. The intracuticular waxes contained comparable levels of very-long-chain components and pentacyclic triterpenoids. The cutin monomers were predominantly C 16 -dihydroxy fatty acids, and other hydroxyl fatty acid derivatives, present with a moderate level as other reported Rosaceae family fruit. Compared to cutin polymers, the cuticular waxes contributed approximately 76.9 % of the total barrier to water loss, with the epicuticular wax layer exhibiting 1.6-fold to the intracuticular wax layer for the barrier efficiency in Sanhua plum fruit. The elucidation of the potential effect of surface lipids on transpiration was likely associated with the structural and chemical distribution of cuticular wax layers within the cuticle.
危险品化学品经营许可证（带存储）