Carotenoid Profiling of Yellow-Flesh Peach Fruit

In this study, the carotenoid profiles and content in 132 cultivars of yellow-flesh peach having different fruit developmental periods (short, middle, and long), fruit surface indumenta (glabrous and pubescent skin), and flesh colors (yellow, golden, and orange) were investigated. We simultaneously analyzed and compared the levels of five carotenoids (lutein, zeaxanthin, beta-cryptoxanthin, alpha-carotene, and beta-carotene) through high-performance liquid chromatography. Large differences in carotenoid content among germplasms were observed, with coefficients of variation ranging from 21.24% to 67.78%. The carotenoid content, from high to low, was as follows: beta-carotene > zeaxanthin > alpha-carotene > beta-cryptoxanthin > lutein. We screened several varieties with high carotenoid content, including zeaxanthin in 'Ruiguang2', beta-cryptoxanthin in 'NJN76' and 'TX4F244C', and beta-carotene and total carotenoids in 'Jintong7', '77-26-7', and '77-20-5'. A longer fruit developmental period was associated with greater beta-carotene accumulation but lowered the zeaxanthin and beta-cryptoxanthin accumulation. The zeaxanthin, beta-carotene, and total carotenoid concentrations significantly increased as the flesh color deepened, but the lutein and alpha-carotene levels remained similar among the three flesh colors. The classification index of the indumenta significantly affected the beta-carotene and total carotenoid content (p < 0.05) and was higher in pubescent than glabrous skin.