Brazilian southeast brown propolis: gas chromatography method development for its volatile oil analysis, its antimicrobial and leishmanicidal activities evaluation

Introduction Propolis is widely used in folk medicine, and many factors can affect its chemical composition, including abiotic factors that can influence plants and bees. Therefore, analytical methods are powerful techniques in the quality control of such products. Objective Develop and validate an analytical method for quantifying volatile compounds in Brazilian brown propolis, and evaluate its biological activities. Methods A gas chromatography flame ionisation detector (GC-FID) analytical method was validated, attending the parameters of international validation guidelines as ANVISA 2017 and ICH 2005, for quantification of compounds present in volatile oils from propolis. Evaluation of cytotoxic, antimicrobial, and leishmanicidal activities of the oil. Results The compounds 1,8-cineole, terpinen-4-ol,alpha-copaene,beta-caryophyllene,gamma-muurolene, nerolidol, spathulenol, and gamma-palmitolactone were isolated from the volatile fraction of a Brazilian brown propolis and used in the method validation. All the validation parameters of the method were satisfactory. The volatile fraction displayed a significant leishmanicidal activity, with half maximal inhibition concentration (IC50) = 21.3 mu g/mL against amastigote forms and IC50= 25.1 mu g/mL against promastigote forms ofLeishmania amazonensis.The oil also displayed an antibacterial effect by inhibiting the growth ofStreptococcus mutansandStaphylococcus aureusat 25 mu g/mL and 50 mu g/mL, respectively, but it was not cytotoxic against AGP-01, He-La and CHO-K1cell lines, with IC50> 100 mu g/mL. Conclusion The GC-FID method can be a useful tool in the quality control of propolis material. The southeast brown propolis showed a high chemical complexity in its volatile fraction, which displayed leishmanicidal activity and bactericidal activity.

Automated summary

An analytical method was developed and validated to quantify volatile compounds in Brazilian brown propolis and evaluate their biological activities. The volatile fraction of propolis showed significant leishmanicidal and bactericidal activities, indicating its potential medicinal value. The analytical method can be a useful tool for quality control of propolis materials.