Potencial de extratos da Schinopsis brasiliensis Engl. para desenvolvimento de produtos odontológicos

Abstract

BACKGROUND: The search for viable alternatives for the treatment of oral infections is important since resistance to antibiotics has become a big problem in medical science. OBJECTIVE: To evaluate the potential of extracts from bark’s Schinopsis brasiliensis Engl. to development of dental products. METHODS: The ethanol and hydroalcoholic extracts were produced by maceration and ultrasound. The liquid-liquid partition was performed with hexane, chloroform and ethyl acetate. The phytochemical screening was performed using the sample solution with standard reagents for quantification of secondary metabolites. The identification and quantification of chemical marker was performed by High Performance Liquid Chromatography (HPLC). Microparticles were produced in by spray dryer. The encapsulation efficiency was measured by absorbance difference of encapsulated extract content and the content found on the surface of the microparticles. Thermal degradation was observed by thermogravimetry (TG) and differential thermal analysis (DTA) in a nitrogen atmosphere. The cytotoxic potential was analyzed based on the potential Hemolyzing and the selectivity index (SI) of the samples. In addition, the antibacterial activity was evaluated based on minimum inhibitory concentration (MIC) against ATCC standard strains of Streptococcus mutans, Streptococcus mitis, Streptococcus oralis, Streptococcus salivarius, Staphylococcus aureus and Enterococcus faecalis, as well as a clinical isolate of E. faecalis and testing by bioautography. The sample with better outcome in these tests was subjected to characterization by Gas Chromatography / Mass Spectrometry (G/MS) as well as the process of separation by column chromatography. RESULTS: Gallic acid was identified as a major compound in the samples analyzed. All samples were able to inhibit the growth of the microorganisms, with the exception of E. faecalis clinical isolate, in a concentration of ≤ 1.0 mg/mL and showed no cytotoxicity up to 22 SI. The ethanol extract absorbs less heat than their fractions. All samples exhibit exothermic peak compatible with the degradation of gallic acid. The fraction that showed the best antimicrobial activity was the hexane fraction (MIC = 0.125 mg / mL), subsequently used to perform the chromatography column and bioautography, resulting in 12 new subfractions. The fraction G showed a MIC lower than hexane fraction against E. faecalis, 0.063 mg/mL. GC/MS revealed the presence of β-sitosterol in the hexane fraction. The microparticle produced with a flow rate of 0.4 mL/min showed the highest encapsulation efficiency (88%) and better MIC (0.250 mg/mL and 0.500 mg/mL) to both E. faecalis, even with the lowest concentration of phytocompounds. Only the hydroalcoholic extract used for making the microparticles showed flavonoids (10.16 mg). The microparticle 4 absorbs more heat than all other samples, degrading more than the others. CONCLUSION: All tested samples from S. brasiliensis Engl. showed potential to be used as a basis for the development of dental products for combating oral infections.