Validation of an extraction method on whole pericarp of grape berry (Vitis vinifera L. cv. Shiraz) to study biochemical and molecular aspects of flavan-3-ol synthesis during berry development.
An extraction method on grape berry was optimized for the total flavan-3-ol content measurement with regard to the nature of the sample and the duration of its extraction. This extraction was performed for the first time on the whole pericarp. Flavan-3-ol extractions were achieved on Shiraz ripe samples of pericarp versus skin within different durations: the best results were obtained for the whole pericarp and 1 h duration. Therefore, this more convenient protocol was used to investigate the flavan-3-ol content at different stages through berry development, in parallel with the abundance of transcripts involved in their biosynthesis. Furthermore, flavan-3-ol extractions on pericarp analysis confirmed their presence in both pulp and skin. For the first time, the flavan-3-ol biosynthesis in pulp was demonstrated with both biochemical and transcriptomic analyses since the presence of leucoanthocyanidin reductase (LAR2) and anthocyanin reductase (ANR) transcripts was revealed by real-time PCR. In addition, the percentage of epigallocatechin was different in pulp and skin.
Verries
Clotilde
C
Unité Mixte de Recherche Sciences Pour l'OEnologie, INRA-Montpellier SupAgro 2, place Pierre Viala, F-34060 Montpellier cedex 2, France.
Guiraud
Jean-Luc
JL
Souquet
Jean-Marc
JM
Vialet
Sandrine
S
Terrier
Nancy
N
Ollé
Didier
D
D000872:Anthocyanins / Q000378:metabolism; D002392:Catechin / Q000031:analogs & derivatives / Q000032:analysis; D005419:Flavonoids / Q000032:analysis / Q000096:biosynthesis*; D005638:Fruit / Q000737:chemistry* / Q000254:growth & development* / Q000378:metabolism; D010088:Oxidoreductases / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D027843:Vitis / Q000737:chemistry*
D000872:Anthocyanins; D005419:Flavonoids; D012333:RNA, Messenger; C404987:flavan-3-ol; D002392:Catechin; D010088:Oxidoreductases; C057580:gallocatechol