Abstract

Fiatoa Barthelemy*, Ralaivaon-dratsitonta Jumael Edith Fabrice, Tiandreny Hazara Jipaty, Rainimanantsoa Jenosusbel, Moulis Claude and Fatiany Pierre Ruphin

ABSTRACT

Brochounera madagascariensis (Myristicaceae) is an endemic plant species, distributed in the Eastern and the South-Eastern regions of Madagascar. During an ethno-botanical survey conducted in the South-Eastern of Madagascar, it was reported that Brochounera madagascariensis is traditionally used by the local communities to treat asthma, hypertension, bacterial infections and for wound-healing. The Aim of the study was to evaluate the chemical composition and antimicrobial activity of essential oil from the leaves of Brochounera madagascariensis. The plant species B. madagascariensis was selected based on its relative citation frequency (use value= 0.65) and the informant consensus factor value (0.38) and collected in Alanirano village, district of Fort-Dauphin (Southeast of Madagascar) on December 2023 and identified at the Department of Botany, Tsimbazaza Zoological and Botanical Park, Antananarivo, Madagascar. Essential oil was isolated from the root bark of this plant species by hydro-distillation. Antimicrobial activities were carried out using agar disc diffusion and micro-dilution broth methods with Gram-positive and Gram-negative bacteria as models. The chemical compositions of the essential oils were determined by Gas chromatography-Flame Ionization Detector (GC-FID) and Gas chromatography-Mass spectrometry (GC/MS). Analysis of the leaves essential oil of B. madagascariensis by GC-FID and GC/MS enabled the identification of 41 compounds corresponding to 96.02 % of the total essential oil composition. Based on functional groups classification, the essential oil from the leaves essential oil of B. madagascariensis contained 80.16% of terpenic hydrocarbons, and 15.86% of oxygenated terpenic functions. The major compounds were α-thuyène (16.37%), α-pinène (15.46%), Terpinolène (11.33%), β-myrcène (8.31%), β-pinène (7.44%), α-terpineol (6.47%), Limonene (5.94%), ϒ-terpinène (5.61%), Sabinene (2.80%), α-terpinène (2.68%), Linalol (2.24%), Trans-p-menth-2-ène-1-ol (1.36%), 8-hydroxy-4-ène-3-one (1.34%), Cis-cis-dihydro-p-menthenolide (1.27%), 1, 8-cinéol (1.21%), p-cymène (1.11%) and piperitenone (1.07%).The essential oil from the root bark of H. voyronii originated from Madagascar showed bactericidal activity (MBC/MIC ≤ 4).