ABSTRACT
Objective:To evaluate the antibacterial activity and neuroprotective capacity of the ethanolic and aqueous extracts of Tarenaya spinosa (T.spinosa) as well as to determine and quantify some of its polyphenols by high performance liquid chromatography with diode-array detection (HPLC-DAD).Methods:The bacterial Escherichia coli,Staphylococcus aureus and Pseudomonas anuginosa strains,grown in Heart Agar Infusion,were tested.The drugs gentamicin,norfloxacin and imipenem were used to evaluate the modulating or antagonistic capacity of the T.spinosa extracts.The extract was analysed by HPLC-DAD to determine the main phenolic compounds.For the cell viability tests.individual heads of the Nauphoeta cinerea arthropod model were removed,homogenized in Trifluoromethyl ketone and centrifuged afterwards.Subsequently,20 μL of NaNO2 were added to the biological material,except in the control group,to evaluate the protection capacity of the extracts.The homogenate of the insect heads was incubated for 2 h in tubes containing tetrazolium bromide.Results:HPLC-DAD demonstrated that the ethanolic extract of T.spinosa presented caffeic acid as the major compound.The ethanolic extract also showed neuroprotective effects at concentrations ≥ 10 μg/mL,while aqueous extract was shown to have a protective effect only at the concentration of 100 μg/ mL.The aqueous extract demonstrated a clinically relevant antibacterial activity against the Staphylococcus aureus multidrug resistant strain-MDR,with MIC 512 μg/mL.However,when the extracts were associated with gentamicin and imipenem,a synergism was detected against Staphylococcus aureus and Escherichia coli MDR strains.Conclusions:Although it does not present an antibacterial action,the extracts of T.spinosa can be used in the pharmaceutical industries since its extracts show modulating action of drugs.Besides,these natural products have neuroprotective capacity.