Estudo fitoquímico da espécie Serjania lethalis St. Hil.

Abstract

The brazilian is biodiversity considered one of higher of the world, is a bit know and explored as the source of drugs medicines. In search of new bioactive molecules the etanolic extract of stem of Serjania lethalis St. Hil was studied in for the molluscicide, miracicide and shistossomicida activity. The specie S. lethalis was collected in Brasilia and a voucher is deposited in the Herbarium of Federal University of Brasilia under the number JEP 3698 UB. After dried end reduced to powder the stem of S. lethalis was extracted in Soxhlet apparatus with ethanol 95%. The crude ethanol extract of stem was extracted, at low temperature, with acetone. The soluble fraction in acetona was purified through filtration in active charcol and permeation in sephadex gel LH 20 and additional preparative chromatographic plate for the obtention of saponin codified as SLS. An alternative method of separation involving the use of synthetic membranes that provide dialysis was used for hidrometanolic and ethyl acetate fractions obtained from the partition of the liquid-liquid crude ethanol extract (stem). Due to the antibacterial activity observed after dialysis follow up purification was made, using chromatography techniques on column with deacttived sílica and subsequent purification in Sephadex LH 20 column to obtain the SLD substance. The butanolic fraction obtained from liquid-liquid partition was active against Biomphalaria glabrata with CL90 10,62 μgmL-1 in 24 hours. The fraction soluble in acetone showed excellent inhibition halo against Pseudomonas aeruginosa. The chemical structures of pure substances SLS, 3-O-[β-Ogalactopyranosyl (1 4)-α ramnopiranosil (1 2) α-ramnopiranosil and SLD, O-β Dfructofuranosil-( 2 4)-D - glucose were proposed based on data from unidimensional Nuclear Magnetic Resonance (NMR) (NMR 1H, NMR 13C, DEPT 135) and two-dimensional (COSY, HSQC and HMBC). The in vitro test showed that the substance codified as SLS was active against S. mansoni.