PSII inhibitory activity of resorcinolic lipids from Sorghum bicolor

J Nat Prod. 2003 Jan;66(1):42-5. doi: 10.1021/np0203842.

Abstract

Resorcinolic lipids were isolated from the root extracts of Sorghum bicolor and identified as 4,6-dimethoxy-2-[(8'Z,11'Z)-8',11',14'-pentadecatriene]resorcinol (4), 4-methoxy-6-ethoxy-2-[(8'Z,11'Z)-8',11',14'-pentadecatriene]resorcinol (5), and 4-hydroxy-6-ethoxy-2-[(10'Z,13'Z)-10',13',16'-heptadecatriene]resorcinol (6). Compounds 4 and 5 inhibited photosynthetic oxygen evolution (IC50 0.09 and 0.20 microM, respectively). Compound 4 could not be enzymatically converted to a quinone, suggesting that the quinone moiety is not required for its photosystem II inhibitory activity. Compounds 5 and 6 are reported for the first time.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Chlorophyll / metabolism
  • Germination / drug effects
  • Inhibitory Concentration 50
  • Lactuca / drug effects
  • Light-Harvesting Protein Complexes
  • Lipids / chemistry
  • Lipids / isolation & purification*
  • Lipids / pharmacology
  • Molecular Structure
  • Nuclear Magnetic Resonance, Biomolecular
  • Photosynthesis / drug effects*
  • Photosynthetic Reaction Center Complex Proteins / chemistry
  • Photosynthetic Reaction Center Complex Proteins / metabolism*
  • Photosystem II Protein Complex
  • Plant Roots / chemistry
  • Poaceae / chemistry*
  • Quinones / metabolism
  • Resorcinols / chemistry
  • Resorcinols / isolation & purification*
  • Resorcinols / pharmacology
  • Stereoisomerism

Substances

  • Light-Harvesting Protein Complexes
  • Lipids
  • Photosynthetic Reaction Center Complex Proteins
  • Photosystem II Protein Complex
  • Quinones
  • Resorcinols
  • Chlorophyll