The main products of the low molecular mass fraction in the venom of the spider Latrodectus menavodi.

The low molecular mass fraction of the venom of the spider Latrodectus menavodi, a black widow spider domiciled in Madagascar, was analyzed with HPLC combined with electrospray mass spectrometry as lyophilized powder and as freshly milked liquid venom. The main components were found to be the purine derivatives adenosine (1), guanosine (2), inosine (3), and 2,4,6-trihydroxypurine (4). Compounds 1-3 are known as components of spider or snake venoms, but they have never been found previously in the venom of the species Latrodectus, whereas compound 4 has not previously been found in any spider venoms. The lyophilized and unlyophilized venoms were found to have identical composition.