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• The first integrated proteomic and metabolomic study on the carotenoid biosynthesis in banana. • Up-regulation of carotenogenesis-associated genes contributes to increased carotenoid level. • High rates of glycolysis are likely required to support carotenoid biosynthesis. To gain a better understanding concerning factors underlying carotenoid metabolism in banana pulp we investigated the carotenoid profile, metabolome, proteome and relative expression levels of carotegenesis-associated genes of fruit pulp in the two banana varieties ON and GN, with ON being characterized of high carotenoid accumulation. Results showed that high carotenoid content in banana pulp was well correlated with the relative expression of carotenogenesis-associated genes and the abundance of the corresponding proteins. An elevated accumulation of sugar metabolism-related compounds and a decreased amino acid accumulation were also observed in ON. Additionally proteins involved in the glycolytic pathway were more highly abundant in ON suggesting that this supports the higher accumulation of carotenoid in this genotype. We suggest that up-regulated expression of carotenogenesis-associated genes alongside elevated carbohydrate accumulation contribute to high carotenoid content in banana pulp, implying that a multi-target approach is necessary in order to improve carotenoid content in banana. [ABSTRACT FROM AUTHOR]

Highlights • First comprehensive identification on phenolics of septum of walnut. • Seventy-five phenolics were identified/tentatively identified. • Seven flavonols were first reported in walnut plant. • Flavonoids and hydrolysable tannins were the major polyphenols of walnuts. Abstract Walnut (Juglans regia L.) is an abundant source of polyphenols. Although phenolic species in the walnut kernel have been studied comprehensively, their compositional profile in the internal fruit septum, a traditional nutraceutical material in China, has been rarely explored. In the current study, the methanolic extract of the walnut septum was analysed by Ultra-performance liquid chromatography coupled with Orbitrap mass spectrometry. Totally seventy-five phenolics belonging to flavonoids, tannins and phenolic acids were identified based on mass spectra, references and literatures. Among them, quercetin-3- O -galactoside, quercetin-rhamnose-pentoside, quercetin-3- O -glucoside, quercetin-rhamnose-hexoside, kaempferol-rhamnoside, and two isomers of quercetin-rhamnoside were reported for the first time in walnut. The total polyphenol content was found to be 122.78 ± 2.55 mg GAE/g dry weight in septum. This study is the first to comprehensively investigate and identify phenolic compounds in the fruit septum of walnut and indicates that the septum to be a rich resource of polyphenols. [ABSTRACT FROM AUTHOR]