Isoprenoid, lipid, and protein contents in intact plastids isolated from mesocarp cells of traditional and high-pigment tomato cultivars at different ripening stages

J Agric Food Chem. 2012 Feb 22;60(7):1764-75. doi: 10.1021/jf204189z. Epub 2012 Feb 9.

Abstract

This study reports quali-quantitative analyses on isoprenoids, phospholipids, neutral lipids, phytosterols, and proteins in purified plastids isolated from fresh fruits of traditional (Donald and Incas) and high-pigment (Kalvert and HLY-18) tomato cultivars at four ripening stages. In all of the investigated cultivars, lycopene, β-catotene, lutein, and total carotenoids varied significantly during ripening. Chromoplasts of red-ripe tomato fruits of high-pigment cultivars accumulated twice as much as lycopene (307.6 and 319.2 μg/mg of plastid proteins in Kalvert and HLY-18, respectively) than ordinary cultivars (178.6 and 151.7 μg/mg of plastid proteins in Donald and Incas, respectively); differences in chlorophyll and α-tocopherol contents were also evidenced. Phospholipids and phytosterols increased during ripening, whereas triglycerides showed a general decrease. Regardless of the stage of ripening, palmitic acid was the major fatty acid in all cultivars (ranging from 35 to 52% of the total fatty acids), followed by stearic, oleic, linoleic, linolenic, and myristic acids, but their relative percentage was affected by ripening. Most of the bands detected on the SDS-PAGEs of plastid proteins were constantly present during chloroplast-to-chromoplast conversion, some others disappeared, and only one, with a molecular weight of ~41.6 kDa, was found to increase in intensity.

Publication types

  • Comparative Study

MeSH terms

  • Carotenoids / analysis
  • Fruit / chemistry
  • Fruit / growth & development*
  • Fruit / ultrastructure
  • Lipids / analysis*
  • Phytosterols / analysis
  • Pigments, Biological / analysis
  • Plant Proteins / analysis*
  • Plastids / chemistry*
  • Solanum lycopersicum*
  • Species Specificity
  • Terpenes / analysis*

Substances

  • Lipids
  • Phytosterols
  • Pigments, Biological
  • Plant Proteins
  • Terpenes
  • Carotenoids