ANALYSES OF METAL-IONS IN SPIDER VENOMS IN RELATION TO INSECTICIDAL ACTIVITY OF CLAVAMINE

To elucidate insecticidal activity of spider toxins, metal ions in ven oms and in the bodies were determined by thin layer chromatography, sp ark source mass spectrometry, ion chromatography, inductively coupled plasma emission spectrometry and atomic absorption spectrometry. Two k inds of spiders were used, Nephila clavata and Nephila maculata. Metal s from their venom glands were extracted with hydrochloric acid and th e metal concentrations were almost the same in the two species. Many k inds of metals, Fe, Zn, Pb, Cu, Ca, Mg, Na, P and S were found at high er levels in the venoms at concentrations higher than in the bodies. T he contents of metal ions were low in the dragonfly and the cicada whi ch are considered to be preys. Clavamine, the main insecticidal compon ent in N. clavata, was effective on larvae of a mosquito with Ca2+ , F e3+ or Pb2+ , but ineffective with Mg2+, Zn2+, Fe2+ or CU2+. It is sug gested that the metal chelates play an important role in the intoxicat ion and detoxication of the spider toxins.