ABSTRACT
The secondary metabolism products of plants have influenced great economic interest, given their chemical diversity and biological activities. Because of this, this study evaluates the phytochemical composition, antimicrobial activity, insecticidal, and antioxidant activity of plant extracts and oil of Myrcia oblongata. Saponins, steroids, triterpenoids, tannins, and flavonoids were detected. The extracts showed antimicrobial capacity on the tested microorganisms, except for the methanolic extract, which showed no activity for P. mirabilis and S. enteritidis. Regarding the analysis of antioxidant compounds, the hexanic, ethyl acetate and acetone extracts showed higher antioxidant activities and also higher insecticidal performance on Alphitobius diaperinus larvae, resulting in 80% adult mortality. The results reported here show that there may be a relationship between antioxidant potential and the insecticidal effect of Myrcia oblongata DC. The components present in both the extract and the oil can be used as natural alternative to synthetic compounds in the biological control of parasites and pathogenic microorganisms.
Os produtos do metabolismo secundário das plantas têm despertado grande interesse econômico, dada sua diversidade química e atividades biológicas. Neste sentido, o estudo objetivou avaliar a composição fitoquímica, atividade antimicrobiana, inseticida e antioxidante dos extratos vegetais e óleo de Myrcia oblongata. Foram detectados a presença de saponinas, esteróides, triterpenóides, taninos e flavonóides. Os extratos apresentaram capacidade antimicrobiana sobre os microrganismos testados, exceto o extrato metanólico que não demonstrou atividade para P. mirabilis e S. Enteritidis. Quanto a análise de compostos antioxidantes observou-se que os extratos hexânico, acetato de etila e acetona apresentaram maiores atividades antioxidantes e também maior performance inseticida sobre a larva Alphitobius diaperinus e exibindo mortalidade de 80% na fase adulta. Os resultados aqui reportados mostram que pode haver uma relação entre potencial antioxidante e efeito inseticida do óleo de Myrcia oblongata; os componentes presentes tanto no extrato como o oléo podem ser utilizados como alternativa natural aos compostos sintéticos no controle biológico de parasitas e microrganismos patogênicos.
Subject(s)
Animals , Antioxidants/analysis , Coleoptera , Phytotherapy , Insecticides/analysis , Myrtaceae/microbiology , Myrtaceae/chemistry , SalmonellaABSTRACT
Volatiles compounds are involved in defensive induction against insects, playing an important role in insect-plant interaction being induced by response to mechanical damage. However, they could decrease according to the domestication degree in cultivated plants. Currently, it has been established that secondary metabolites are reduced due to the domestication process in murtilla. Hence, the follow question emerges: Are volatile organic compounds induced by mechanical damage reduced in cultivated murtilla plants in relation to wild plants? Two cultivated ecotypes and their respective wild counterparts were sampled. Volatiles compounds were obtained using Porapak-Q columns and analyzed by gas chromatography. Results showed that compounds as 2-hexanone, α-pinene, 2-thujene, 3-thujene and 1,8- cineole were more abundant in wild plants exposed to a mechanical damage than cultivated plants. Hence, these compounds have been associated to induced defense, these results suggest that domestication reduced the induction of defensive volatiles in cultivated murtilla in response to mechanical damage.
Los compuestos volaÌtiles estaÌn implicados en la defensa inducida contra insectos, desempenÌando un papel importante en esta interaccioÌn. Sin embargo, estos compuestos podriÌan disminuir seguÌn el grado de domesticacioÌn. Actualmente, se ha reportado que algunos metabolitos secundarios son reducidos en plantas de murtilla domesticadas. Por lo tanto, surge la siguiente pregunta de investigacioÌn: ¿Los compuestos orgaÌnicos volaÌtiles inducidos por el danÌo mecaÌnico son reducidos en plantas cultivadas de murtilla en comparacioÌn con plantas silvestres? Para dos ecotipos cultivados y sus respectivas contrapartes silvestres, los compuestos volaÌtiles fueron capturados usando columnas de Porapak-Q y las muestras analizadas por cromatografiÌa gaseosa. Los resultados mostraron que compuestos tales como 2- hexanona, α-pineno, 2-tujeno, 3-tujeno y 1,8-cineol fueron maÌs abundantes en plantas silvestres expuestas a danÌo mecaÌnico que en cultivadas. Debido a que estos compuestos se han asociado a defensa inducida, estos resultados sugieren que la domesticacioÌn reduce la induccioÌn de volaÌtiles en plantas cultivadas sometidas a danÌo mecaÌnico.
Subject(s)
Animals , Oils, Volatile/metabolism , Myrtaceae/metabolism , Myrtaceae/microbiology , Domestication , Insecta/physiology , Sesquiterpenes/analysis , Sesquiterpenes/metabolism , Oils, Volatile/chemistry , Myrtaceae/chemistry , Monoterpenes/analysis , Monoterpenes/metabolism , Wilderness , Larva/physiology , Gas Chromatography-Mass SpectrometryABSTRACT
Beneficial interactions between plants and microorganisms have been investigated under different ecological, physiological, biochemical, and genetic aspects. However, the systematic exploration of biomolecules with potential for biotechnological products from this interaction still is relatively scarce. Therefore, this study aimed the evaluation of the diversity and antimicrobial activity of the endophytic fungi obtained from roots, stems and leafs of Myrcia guianensis (Myrtaceae) from the Brazilian Amazon. 156 endophytic fungi were isolated and above 80% were identified by morphological examination as belonging to the genera Pestalotiopsis, Phomopsis, Aspergillus, Xylaria, Nectria, Penicillium and Fusarium. Fermented broth of those fungi were assayed for antimicrobial activity and four inhibited the growth of Staphylococcus aureus, Enterococcus faecalis, Candida albicans and Penicillium avellaneum. As the strain named MgRe2.2.3B (Nectria haematococca) had shown the most promising results against those pathogenic strains, its fermented broth was fractioned and only its two low polar fractions demonstrated to be active. Both fractions exhibited a minimum bactericidal concentration of 50 µg.mL-1 against S. aureus and a minimum fungicidal concentration of 100 µg.mL-1 against P. avellaneum. These results demonstrate the diversity of fungal genera in M. guianensis and the potential of these endophytic fungi for the production of new antibiotics.
Subject(s)
Anti-Infective Agents/metabolism , Biodiversity , Endophytes/classification , Endophytes/isolation & purification , Fungi/classification , Fungi/isolation & purification , Myrtaceae/microbiology , Brazil , Bacteria/drug effects , Endophytes/metabolism , Fungi/drug effects , Microbial Sensitivity Tests , Plant Leaves/microbiology , Plant Roots/microbiology , Plant Stems/microbiologyABSTRACT
O presente trabalho teve como objetivo determinar a composição química e avaliar a atividade antimicrobiana dos óleos essenciais obtidos das folhas (frescas e secas) e flores da Callistemon viminalis. Os óleos essenciais foram analisados por CG/EM. A concentração inibitória mínima (CIM) foi determinada utilizando o método de microdiluição em caldo frente a bactérias Gram-positivas e Gram-negativas. De um total de 96,72%, 98,70% dos compostos identificados nos óleos essenciais foram monoterpenos. O 1,8-cineol foi o componente majoritário no óleo essencial das folhas frescas (70,43%), folhas secas (71,71%) e flores (42,39%), seguido do tricicleno com 12,97% nas folhas frescas, 8,20% nas folhas secas e 28,08% nas flores. A CIM para todos os micro-organismos testados foi ≥ a 2.000 μg/mL. Esse estudo é o primeiro relato sobre a composição química e atividade antimicrobiana do óleo essencial das flores de C. viminalis.
The aim of this study was to determine the chemical composition and the antimicrobial activity of essential oils of Callistemon viminalis leaves (fresh and dried) and flowers. The essential oils were analyzed by GC/MS and the minimum inhibitory concentration (MIC) against Gram-positive and Gram-negative bacteria was determined by the broth microdilution method. Between 96.72% and 98.70% of the compounds identified in the essential oils were monoterpenes. 1,8-Cineole was the major component in the essential oils of fresh leaves (70.43%), dried leaves (71.71%) and flowers (42.39%), followed by tricyclene: 12.97% in the fresh leaves, 8.20% in the dried leaves and 28.08% in the flowers. The MIC for all microorganisms tested was ≥ 2,000 μg/mL, for all the essential oil samples. This study is the first report on the chemical composition and antimicrobial activity of essential oil from the flowers of C. viminalis.