Seasonal variation and antimicrobial activity of Myrcia myrtifolia essential oils

Abstract

Os óleos essenciais das folhas, flores e frutos de Myrcia myrtifolia DC foram coletados ao longo dos anos de 2002 e 2003 e foram analisados utilizando CG-DIC e CG-EM. No total foram identificados 28 componentes sendo que o α-pineno foi a substância predominante em todas as amostras analisadas apresentando-se em concentrações que variaram entre 61.5 e 90.9%. As propriedades antimicrobianas do óleo essencial das folhas coletadas em outubro de 2002 foram avaliadas contra seis bactérias, duas leveduras e cinco fungos filamentosos sendo mais fortemente ativo contra Microsporum canis e Trichophyton rubrum, ativo contra Staphylococcus aureus, Staphylococcus aureus resistente à meticilina, Candida albicans, Cryptococcus neoformans e Aspergillus fumigatus. O óleo ainda mostrou uma toxicidade moderada, LC 50 of 479,16 μg mL -1 , contra Artemia salina.This work reports the seasonal variation of the composition of leaf volatile oils and the composition of volatile oils from flowers and fruits of Myrcia myrtifolia DC harvested in the sand dunes of Salvador, Bahia, northeastern region of Brazil between 2002 and 2003. The oils were analyzed by GC-FID and GC-MS so that 28 components were identified. α-Pinene was predominant in a range from 61.5 to 90.9% in all samples analyzed. The leaf oil collected in October 2002 had their antimicrobial properties tested against six bacteria, two yeasts and five filamentous fungi being active against Staphylococcus aureus, methicilin-resistant Staphylococcus aureus, Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus, and showed strongest activity against Microsporum canis and Trichophyton rubrum. The oil displayed moderate toxicity against Artemia salina showing a LC 50 of 479.16 μg mL -1 .Keywords: Myrtaceae, Myrcia myrtifolia, essential oil, monoterpene, sesquiterpene, antimicrobial activity IntroductionAromatic plants have been used since ancient times as antiseptics and anti-infectious agents, as aroma in perfumes and cosmetics as well as preservative and flavour ingredients in food and beverages. Their biological properties are directly related with their chemical compositions, which can be affected by environmental, geographical, seasonal and circadian variations.The family Myrtaceae is constituted by 140 genera with about 3000 species, which are widely distributed in America and Australia. 1 The genus Myrcia comprises more than 300 species that grow in all Brazilian territory. Indigenous tribes and traditional Brazilian communities have used several species of this genus as astringent, against diabetes and diarrhea, as diuretic, to stanch hemorrhages, against the hypertension and ulcers of the mouth. 2 Some works were published regarding the chemistry and the biological properties of Myrcia species. From M. citriofolia, the occurrence of a C-methylated flavone, eucalyptin, was related, 3 from the methanolic extract of M. multiflora were isolated flavonol, flavanone and acetophenone glucosides along with myricitrin, mearnssitin, quercitrin, desmanthin-1 and guaijaverin...

Essential oils in aerial parts of Myrcia tomentosa: composition and variability

“…(2E,6E)-Methyl farnesoate (14.39%) and hexadecanoic acid (22.05%) were the main compounds found in the stem bark, while in the flowers, the main compounds were espathulenol (7.36%), (2Z,6Z)-farnesol (10.65%) and (2E,6E)-methyl farnesoate (14.28%). Sesquiterpenes were predominant in the flowers, as has previously been found in Myrcia fallax; however, guaiol (27.5%) and aristolone (24.5%) were the primary compounds found in Myrica fallax, while monoterpenes, represented by α-pinene were the main components (62-87.3%) present in Myrcia myrtifolia DC (Cerqueira et al, 2007;Alarcón et al, 2009).…”

“…The work of Cerqueira et al (2007) on seasonal variation and antimicrobial activity and Alarcón et al (2009) on chemical composition and antibacterial activity are examples of such antimicrobial studies for the genus Myrcia. Souza (2009) analyzed the chemical composition of nine species of the Myrtaceae family, two of which belonged to the genus Myrcia, Limberger et al (2004) analyzed the composition of nine species of the genus Myrcia, and Zoghbi et al (2003) analyzed three species.…”

“…The genus Myrcia has 300 species (Judd et al, 2009), for which a range of pharmacological activities have been described (Hecht, 1984;Almeida, 1993;Cerqueira et al, 2007;Xu et al, 2011). Within this genus, Myrcia tomentosa, popularly known as "goiababrava", can be found from Panama, northern Venezuela and Guyana to southeast Brazil (McVaugh, 1969) and is often cited in works on the flora, phytosociology and characterization of the Savanna/Cerrado (Mahmoud et al, 2003;Teixeira et al, 2004;Morais & Lombardi, 2006).…”

In vitro antifungal activity and cytotoxic effect of essential oils and extracts of medicinal and aromatic plants against Candida krusei and Aspergillus fumigatus

“…Samaranayake et al (1995) demonstrated that C. krusei is more hydrophobic than other species. This physicochemical characteristic could at least partly explain the susceptibility of this yeast to the oils due to the hydrophobic nature of the majority of the components of the essential oil (de Cerqueira et al, 2007).…”

“…This difference in antifungal activity between essential oils from plants of the same species can be explained by the chemotype (chemical composition), geographical region of plant collection, age of plant, extraction method of oils, method used to assess the antifungal activity or by the intra or inter species differences (Samaranayake et al, 1995;Cruz et al, 2007;Maksimovic et al, 2008). Sharma & Tripathi (2008) have shown that the antifungal activity of essential oils is better evaluated in liquid than in solid media, since in the latter, the hydrophobic nature of the majority of essential oil components hamper uniform diffusion of these substances through the agar medium (de Cerqueira et al, 2007). We used the standard microdilution methods M38-A and AFST-EUCAST for the evaluation of antifungal susceptibility of filamentous fungi and yeasts, respectively.…”