On the origin of oil droplets in maturing castor bean seeds,Ricinus communis

Fat droplets isolated from maturing castor bean seeds contain high concentrations of fatty acid synthetase and triglyceride synthesizing enzymes. These activities are not due to contamination by other organelles and account for at least 80% of the total lipid synthesis. Electron microscopy of the isolated oil droplets and the seed tissue in vivo revealed particulate containing vacuole-like inclusions which, it is suggested, are the site of lipid synthesis and which form the original locus of the droplet.