Metabolomics of dates (Phoenix dactylifera) reveals a highly dynamic ripening process accounting for major variation in fruit composition

BMC Plant Biology

Research Article

Anna Halama¹  Karsten Suhre¹  Sweety Mathew¹  Ilhame Diboun¹  Maryam Al-Rayyashi²  Maria Torres²  Joel Malek³  Mohamed Elrayess⁴  Michaël Méret⁵  Robert P. Mohney⁶  Edward D. Karoly⁶ 

[1] Department of Physiology and Biophysics, Weill Cornell Medical College, Qatar Foundation – Education City, PO Box 24144, Doha, Qatar;Genomics Laboratory, Weill Cornell Medical College, Doha, Qatar;Genomics Laboratory, Weill Cornell Medical College, Doha, Qatar;Department of Genetic Medicine, Weill Cornell Medical College, Doha, Qatar;Life sciences research division, Doha, ADLQ, Qatar;MetaSysX GmbH, Potsdam, Germany;Metabolon, Inc., Durham, USA;

关键词: Date fruit;    Ripening;    Metabolomics;    Date palm;    Soft dates varieties;    Dry dates varieties;    SIMCA;    OPLS;    PCA;    Multivariate;   

DOI  :  10.1186/s12870-015-0672-5

 received in 2015-07-08, accepted in 2015-12-03,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundDates are tropical fruits with appreciable nutritional value. Previous attempts at global metabolic characterization of the date metabolome were constrained by small sample size and limited geographical sampling. In this study, two independent large cohorts of mature dates exhibiting substantial diversity in origin, varieties and fruit processing conditions were measured by metabolomics techniques in order to identify major determinants of the fruit metabolome.ResultsMultivariate analysis revealed a first principal component (PC1) significantly associated with the dates’ countries of production. The availability of a smaller dataset featuring immature dates from different development stages served to build a model of the ripening process in dates, which helped reveal a strong ripening signature in PC1. Analysis revealed enrichment in the dry type of dates amongst fruits with early ripening profiles at one end of PC1 as oppose to an overrepresentation of the soft type of dates with late ripening profiles at the other end of PC1. Dry dates are typical to the North African region whilst soft dates are more popular in the Gulf region, which partly explains the observed association between PC1 and geography. Analysis of the loading values, expressing metabolite correlation levels with PC1, revealed enrichment patterns of a comprehensive range of metabolite classes along PC1. Three distinct metabolic phases corresponding to known stages of date ripening were observed: An early phase enriched in regulatory hormones, amines and polyamines, energy production, tannins, sucrose and anti-oxidant activity, a second phase with on-going phenylpropanoid secondary metabolism, gene expression and phospholipid metabolism and a late phase with marked sugar dehydration activity and degradation reactions leading to increased volatile synthesis.ConclusionsThese data indicate the importance of date ripening as a main driver of variation in the date metabolome responsible for their diverse nutritional and economical values. The biochemistry of the ripening process in dates is consistent with other fruits but natural dryness may prevent degenerative senescence in dates following ripening. Based on the finding that mature dates present varying extents of ripening, our survey of the date metabolome essentially revealed snapshots of interchanging metabolic states during ripening empowering an in-depth characterization of underlying biology.

【 授权许可】

CC BY   
© Diboun et al. 2015