A General Survey of the Free Amino Acids in the Genus Vitis

¹ Department of Viticulutre and Enology, University of California, Davis.

Leaves from 23 species and berries from 20 species of Vitis were examined by twodimensional paper chromatography for free amino acids and other ninhydrin-reacting compounds at three stages of development. Thirty-two amino acids were identified in the various species. In addition, eight unidentified amino compounds were detected. Large amounts of free hydroxyproline and an unidentified amino acid were present in immature fruit and leaves (sampled in June and July) of five species: V. aestivalis, V. berlandieri, V. cinerea, V. rufotomentosa, and V. simpsoni 'pixiala'. These two amino compounds were either absent or present in only trace amounts in the other Vitis species examined. Quantitatively, there were large differences between the Vitis species in the concentration of the various amino acids, especially with respect to arginine, proline, and asparagine. Pipecolic acid and homoserine varied both qualitatively and quantitatively among species.