Targeted Metabolomics-Based Analysis of Peel Color Differences Between Yellow and Red Hawthorn
[Objective]The aim of this study was to explore the accumulation pattern of flavonoids and carotenoids of yellow and red hawthorn peel during the fruit ripening process,as well as to deepen the understanding of the coloration mechanism of hawthorn peel,so as to provide the guidance for peel color-directed genetic breeding.[Method]The fruit peel of yellow hawthorn(Crataegus pinnatifida Jinruyi)and red hawthorn(Crataegus pinnatifida Ruanzi)was used as test materials.The components and content of flavonoid and carotenoid in the peel of the two cultivars during different growth stages were examined qualitatively and quantitatively based on targeted metabolomics analysis.The differential accumulation of flavonoids and carotenoid metabolites between the two cultivars was analyzed by the orthogonal partial least squares discriminant analysis(OPLS-DA).[Result]A total of 130 kinds of flavonoids and 49 kinds of carotenoids were detected in the peel of the two hawthorn cultivars,and the components and content of these metabolites were significantly different between the two cultivars during different growth stages.The anthocyanin content of the Ruanzi peel was 400 times higher than that of the Jinruyi peel,which in the Ruanzi peel and Jinruyi peel at the mature period(S5)was 930.04 and 2.32 μg·g-1,respectively.The major anthocyanin species was cyanidin-3-O-galactoside,which accounted for more than 95%of total anthocyanins.The carotenoid metabolism analysis showed that there was no significant difference in total carotenoid content between Ruanzi and Jinruyi during the S1-S3 period,and lutein was the predominant accumulated carotenoid.The content of β-carotene,β-cryptoxanthin,neoxanthin,α-carotene,and zeaxanthin in the Jinruyi peel were significantly higher than that in the Ruanzi peel during the S4-S5 period.The massive accumulation of these carotenoid metabolites in the Jinruyi peel led to the difference in carotenoid content in the two hawthorn cultivars during the S4-S5 period.[Conclusion]In the hawthorn fruit mature period,the accumulation of anthocyanin in the Ruanzi peel led to the appearance of red,and the accumulation of carotenoid in the Jinruyi peel led to the appearance of yellow.The differential accumulation of anthocyanins and carotenoids played an important role in the hawthorn peel different coloration.
hawthornanthocyaninflavonoidcarotenoidmetabolomicspeel color