Methyl jasmonates in developing strawberry fruit (Fragaria ananassa Duch cv Kent)

Two isomeric methyl jasmonates were isolated from extracts of strawberry fruit (Fragaria ananassa Duch. cv. Kent) by means of micropreparative gas chromatography. Enantiomeric separation and comparison with reference compounds allowed the determination of their absolute configuration as (3R,7S)-(+)-methyl epi-jasmonate and (3R,7R)-(-)-methyl jasmonate, respectively. Their genuine content in fruit was monitored throughout the ripening period from 7 days after anthesis (DAA) to the overripe stage (36 DAA). On a per weight basis, the sum of both isomers had a maximum concentration of 277.5 mu g kg(-1) in immature fruits and then steadily decreased. The levels of methyl jasmonates in strawberry may affect aroma formation and further events during fruit development.