No abstract

In this work, chitosan/mangiferin particles (CMP) were prepared by spray-drying technique and characterized by SEM, DLS, FTIR, HPLC-UV and adsorption studies to investigate a possible application as a preventive material in cases of human and animal contamination with Cr(VI). CMP presented sizes ranging from nano to micrometers. Chitosan and mangiferin (MA) presence in the powder was confirmed by FTIR and MA quantification (136 μg/mg) was performed using a calibration curve prepared by HPLC-UV. Adsorption capacity of Cr(VI) onto CMP was compared with chitosan and investigated in a batch system by considering the effects of various parameters like contact time, initial concentration of adsorbent and pH. Cr(VI) removal is pH dependent and it was found to be maximum at pH 5.0. The results showed that CMP has a potential application as a preventive material in cases of human or animal contamination with Cr(VI).

No abstract

Rauvolfia species are well-known as producers of bioactive monoterpene indole alkaloids (MIAs) which exhibit a broad spectrum of biological activities. A new vobasine-sarpagan-type bisindole alkaloid (1) along with six known monomeric indoles (2, 3/4, 5, and 6/7) were isolated from the ethanol extract from the roots of Rauvolfia ligustrina. The structure of the new compound was elucidated by interpretation of their spectroscopic data (1D and 2D NMR and HRESIMS) and comparison with published data for analog compounds. The cytotoxicity of the isolated compounds was screened in zebrafish (Danio rerio) model. The possible GABAergic (diazepam: positive control) and serotoninergic (fluoxetine: positive control) mechanisms of action in adult zebrafish were also evaluated. No compounds were cytotoxic. Compound 2 and the epimers 3/4 and 6/7 showed mechanism action by GABAA, while compound 1 by serotonin receptor (anxiolytic activity). Molecular docking studies showed that compounds 2 and 5 have a greater affinity by GABAA receptor when compared with diazepam, whereas 1 showed the best affinity for 5HT2AR channel when compared to risperidone.