Background: Lippia sidoides (Verbenaceae) is used in Brazilian folk medicine as an antiseptic, and it is usually applied topically on skin, mucous membranes, mouth, and throat, or used for vaginal washings.
Objectives: To analyze the chemical composition of the essential oil from L. sidoides collected in São Gonçalo do Abaeté, Minas Gerais and grown in Hidrolândia, Goiás; to evaluate the antimicrobial activity of the essential oil, crude ethanol extract, and hexane, dichloromethane, ethyl-acetate, and aqueous fractions (AFs); to study the antinociceptive, anti-inflammatory, and central nervous system activities of the crude ethanol extract.
Materials and methods: The essential oils were obtained by hydro-distillation using a Clevenger-type apparatus and analyzed by GC/MS. The antimicrobial activity in vitro was performed by broth microdilution method. The pharmacological tests were performed using female Swiss albino mice.
Results: The major components of the essential oil were isoborneol (14.66%), bornyl acetate (11.86%), α-humulene (11.23%), α-fenchene (9.32%), and 1.8-cineole (7.05%), supporting the existence of two chemotypes of this species. The hexane fraction (HF) had good antifungal activity against Cryptococcus sp. ATCC D (MIC = 31.25 μg/mL) and Cryptococcus gatti L48 (MIC = 62.5 μg/mL). In the pharmacological tests, the crude ethanol extract presented antinociceptive and anti-inflammatory activities.
Conclusion: Given that the ethanol extract of L. sidoides is included in the Formulary of Phytotherapeutic Agents of the Brazilian Pharmacopeia as an anti-inflammatory for oral cavities, the present work provides scientific evidence to back this use and highlight the importance of selecting the appropriate chemotype on the basis of the expected biological response.
Summary: The major components of the essential oil of L. sidoides were isoborneol bornyl acetate, α-humulene, α-fenchene, and 1.8-cineole. The HF had good antifungal activity against Cryptococcus sp. ATCC D and C. gatti L4.The crude ethanol extract of L. sidoides presented antinociceptive and anti-inflammatory activities.The present work provides scientific evidence of the importance of selecting the appropriate chemotype on the basis of the expected biological response. Abbreviations used: UFG: Universidade Federal de Goiás; HF: hexane fraction; DF: dichloromethane fraction; EAF: ethyl acetate fraction; AF: aqueous fraction; MeOH: methanol; MIC: minimum inhibitory concentration; ATCC: American Type Culture Collection; MH: Müller Hinton; DMSO: dimethyl sulfoxide; RPMI: Roswell Park Memorial Institute; NaCl: sodium chloride; μL: microliters; mL: milliliters; μg: microgram; kg: kilogram; h: hour; min: minute; cm: centimeter; COBEA: Brazilian College of Animal Experiments; p.o.:, oral; i.p.: intraperitoneal; s.c.: subcutaneous; SEM: standard error of the mean; RI: retention indices.
Keywords: Anti-inflammatory activity; Lippia sidoides; antimicrobial activity; antinociceptive activity; essential oil.