UC Irvine

Summary: Effects of a nonionic surface active agent (lauroyl/myristoyl di (2‐hydroxyethyl) amide) and one anionic surfactant (sodium (linear) dodecylbenzene sulphonate) on cell ultrastructure were determined using Phalaenopsis protocorms. There were no observable effects after 5 days exposure to 1000 ppm of the nonionic. However, the anionic caused severe damage. Drastic changes in morphology, loss of membranes, swelling of thylakoids and appearance of dense osmophilic granules were evident in chloroplasts. Other effects include disintegration of polysomes into monosomes; swelling of mitochondria; dispersion of chromatin in the nucleus; appearance of unidentified vesicles in the cytoplasm and plasmolysis of cells. These ultra‐structural changes can be attributed to the possible emulsification of membrane lipids as well as precipitation and dispersion of cellular proteins.