Duas novas 2"-etil-furanoflavonas chamadas fistulaflavonas A e B juntamente com seis furanoflavonas conhecidas foram isoladas das hastes da Cassia fistula. As estruturas foram elucidadas por métodos espectroscópicos, incluindo as técnicas de NMR 1D e 2D e espectrometria de massa com ionização por electrospray de alta resolução (HRESIMS), e comparação com dados da literatura. Todos os compostos foram avaliados com relação a citotoxicidade para cinco linhas de células tumorais humanas. Um dos compostos mostrou potente citotoxicidade contra células SHSY5Y e MCF7, com valores de IC50 de 2,6 e 2,7 µmol L-1, respectivamente.

Two new 2"-ethyl-furanoflavones named fistulaflavones A and B together with six known furanoflavones were isolated from the stems of Cassia fistula. The structures were elucidated by spectroscopic methods including extensive 1D, 2D NMR and high resolution electrospray ionization mass spectrometry (HRESIMS) techniques, and comparison with literature data. All the compounds were evaluated for their cytotoxicity against five human tumor cell lines. One of the compounds showed potent cytotoxicity against SHSY5Y and MCF7 cells with IC50 values of 2.7 and 2.6 µmol L-1, respectively.

A polyhistidine-tagged recombinant tegumental protein Schistosoma japonicum very lowdensity lipoprotein binding protein (SVLBP) from adult Schistosoma japonicum was expressed in Escherichia coli. The affinity purified rSVLBP was used to vaccinate mice. The worm numbers and egg deposition recovered from the livers and veins of the immunized mice were 33.5% and 47.6% less than that from control mice, respectively (p<0.05). There was also a marked increase in the antibody response in vaccinated mice: the titer of IgG1 and IgG2a, IgG2b in the vaccinated group was significantly higher than that in the controls (>1:6,400 in total IgG). In a comparison of the reactivity of sera from healthy individuals and patients with rSVLBP, recognition patterns against this parasite tegumental antigen varied among different groups of the individuals. Notably, the average titres of anti-rSVLBP antibody in sera from faecal egg-negative individuals was significantly higher than that in sera from the faecal egg-positives, which may be reflect SVLBP-specific protection. These results suggested that the parasite tegumental protein SVLBP was a promising candidate for further investigation as a vaccine antigen for use against Asian schistosomiasis.