Direct organogenesis of<Emphasis Type="Italic"> Mandevilla illustris</Emphasis> (Vell) Woodson and effects of its aqueous extract on the enzymatic and toxic activities of<Emphasis Type="Italic"> Crotalus durissus terrificus</Emphasis> snake venom

In order to produce explants of Mandevilla illustris (Vell) Woodson for the Cerrado in vitro, the Germplasm Bank of UNAERP, we carried out a micropropagation protocol using MS or MS/3 medium supplemented with different concentrations of 6-benzyladeninepurine (BA), Zeatin or 2-isopentenyladenine for nodal segment growth, and -naphthaleneacetic acid, indole-3-butyric acid (IBA) or 1,4 dithiothreitol for rooting. For nodal segments, all the cytokinins tested yielded similar results. However, 2.22 µM BA is more economical to use. MS/3 medium supplemented with 0.49 µM IBA was the most appropriate medium for rooting, resulting in 29% rooted explants. The crude aqueous extract from the subterranean system (SS) of M. illustris was assayed for its inhibitory action on the enzymatic activity of Crotalus durissus terrificus snake venom, isolated basic phospholipase A₂ (CB) and crotoxin. It totally inhibited the phospholipase activity of crude Cdt venom and CB toxin and inhibited the phospholipase activity of crotoxin by 49%. The toxic action of both the crude venom and crotoxin was partially inhibited—there was a prolonged survival time and a 40.0% decrease in lethality.Abbreviations BA: 6-Benzyladeninepurine - CB: Crotalus durissus terrificus basic phospholipase A₂ - Cdt: Crotalus durissus terrificus crude venom - DTT: 1,4 Dithiothreitol - IBA: Indole-3-butyric acid - 2ip: 2-Isopentenyladenine - MiHD: Minimum indirect hemolytic dose - NAA: -Naphthaleneacetic acid - PBS: Phosphate-buffered saline solution - Spermidine: (n-3-Aminopropyl]-1,4-butanediamine) - SS: Subterranean system - TDZ: Thidiazuron - Zeatin: (6-4-Hydroxy-3-methylbut-2-enylamino]purine) Communicated by C.F. Quiros