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The Vitex genus (Lamiaceae) produces a plethora of metabolites that include ecdysteroids and terpenoids, some of which have demonstrated insect repellent properties. The volatile composition of several members of this genus has not been chemically defined, as many taxa are endemic to remote ecosystems. In this study, leaves were collected from the northeast of Brazil from Vitex capitata, V. megapotamica, V. gardneriana and V. rufescens plants and examined for their chemical profile via GC-MS/FID of essential oil extracts. The analyses showed a diversity of terpenoids. Of particular note were seven-member ring sesquiterpenes which were present in great abundance; a dendrogram showed clades separating by the production of (+)-bicyclogermacrene, aromadendrane and 5,10-cycloaromadendrane sesquiterpenoids for the four species. Comparison of volatile metabolite profiles to 13 other Vitex species showed strong similarities in the production of some monoterpenes, but varied by their production of larger terpenes, especially those with gem-dimethylcyclopropyl subunits on seven-member ring compounds. From this work, we suggest that the sesquiterpene skeleton with seven member rings is a good chemosystematic biomarker candidate for the Vitex genus. Separation using this biomarker was then validated using Inter-Simple Sequence Repeat (ISSR) profiling. Lastly, experiments examining the toxicity of these four oils against the coconut mite A. guerreronis showed that only the oil of V. gardneriana had strong acaricidal activity, with an LC50 of 0.85 mg/mL, thus demonstrating its potential for use as a natural pesticide.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Aceria guerreronis keifer is one of the main coconut pests in Brazil, its attack causes a premature fall, reduction of fruit size, water weight and volume, as well as stetic esthetic damages (necrosis) depreciating the product. Currently, there are five pesticides registered for the control of the coconut-necrotic mite. However, there is no specificity to A. guerreronis. The Lamiaceae family stands out with some specimens with notable insecticidal activity, among them the Vitex genus, known to have ecdysteroids and iridoids as markers of the genus. However, there is a shortage of specific chemotaxonomic studies for volatile compounds. The objective of this work was to identify the volatile compounds present in the essential oils of the species of Vitex gardneriana Schauer, Vitex capitata Vahl., Vitex rufescens A. Juss., Vitex megapotamica (Spreng.) Moldenk and to evaluate possible effects of toxicity and repellence against A. guerreronis. In addition to analyzing the genetic diversity of species of the genus Vitex using ISSR markers, verifying the occurrence of statistical correlations between the genetic diversity and the chemical profiles of the essential oils. Chromatographic and spectroscopic techniques (GC-MS / FID) were used for the detection of volatile compounds, and the molecular markers of ISSR for the genetic characterization of the species, as well as toxicity and repellency tests against necrotic necrosis. The results showed 46, 45, 41 and 37 constituents for V. capitata, V. megapotamica, V. gardneriana and V. rufences respectively, among which, -copaene, (E)-caryophyllene, -elemene, -humulene, trans-cadine-1(6)4-diene, viridiflorene and -cadinene were the main components of V. capitata and V. megapotamica. 6,9-guaiadiene, caryophyllene oxide, L-calamenene for V. gardneriana and (E)-cariophylene, ledol, germacrene D, -humulene, allo-aromadendrene, viridiflorene and -elemene for V. rufences. The results of molecular markers of ISSR generated a total of 90 fragments, of which 100% were polymorphic. The genotypes of the four Vitex species selected for this study were pooled using the Jaccard coefficient (JC). The mean similarity was 0.21 JC (0.08-0.45 JC). A clear separation of two groups was observed, with V. gardneriana being the most isolated of the four species, and V. capitata and V. megapotamica more closely related to each other. The acaricide activity of the four oils was also evaluated by means of toxicity and repellency tests against A. guerreronis. The essential oil of V. gardneriana showed acaricidal activity against A. guerreronis with a LC50 of 0.85 mg.mL-1, whereas the oils of V. capitata, V. megapotamica and V. rufecens were not toxic to this pest up to 2.3 mg. Ml-1 when tested through the toxicity bioassay. In general, essential oils distilled from the Vitex species repelled A. guerreronis after 24 hours at a concentration of 1.8 mg.mL-1 using abamectin as a control in the two-choice disc repellency assay, however, the essential oil of V. gardneriana presented a statistically significant acaricidal activity against the coconut mite necrosis. Introducing himself as a potential candidate for the development of an acaricide product. O ácaro-da-necrose-de-coqueiro Aceria guerreronis keifer é uma das principais pragas de coqueiro do Brasil, seu ataque causa queda prematura, redução no tamanho e peso dos frutos e volume de água, além dos danos estéticos (necroses) na casca que diminui o valor comercial do produto. Atualmente, existem cinco agrotóxicos registrados para o controle dessa praga. No entanto, não há especificidade ao A. guerreronis. A família Lamiaceae se destaca com alguns exemplares com notória atividade inseticida, dentre eles, o gênero Vitex, conhecido por possuir dentre seus constituintes os ecdisteroides e iridoides como marcadores do gênero, todavia, há uma escassez de estudo quimiotaxonômicos específicos para compostos voláteis. O objetivo deste trabalho foi identificar os compostos voláteis presentes nos óleos essenciais das espécies de Vitex gardneriana Schauer, Vitex capitata Vahl., Vitex rufescens A. Juss., Vitex megapotamica (Spreng.) Moldenk e avaliar possíveis efeitos de toxicidade e repelência frente ao A. guerreronis, além de analisar a diversidade genética de espécies do gênero Vitex. Técnicas cromatográficas e espectroscópicas (CG-MS/FID) foram utilizadas para detecção dos compostos voláteis, e os marcadores moleculares de ISSR foram empregados para a caracterização genética das espécies, além de testes de toxicidade e repelência contra ao àcaro-da-necrose. Os resultados mostraram 46, 45, 41 e 37 constituintes para V. capitata, V. megapotamica, V. gardneriana e V. rufences respectivamente, dentre os quais, -copaeno, (E)-cariofileno, -elemeno, -humuleno, trans-cadina-1(6),4-dieno, viridiflorene e -cadineno foram os principais componentes de V. capitata e V. megapotamica. 6,9- guaiadieno, óxido de cariofileno, L-calameneno para V. gardneriana e (E)-cariofileno, ledol, germacreno D, -humuleno, allo-aromadendreno, viridifloreno e -elemene para V. rufences. Os resultados dos marcadores moleculares de ISSR geraram um total de 90 fragmentos, dos quais 100% foram polimórficos. Os genótipos das quatro espécies de Vitex selecionadas para este estudo foram agrupados utilizando o coeficiente Jaccard (JC). A média de similaridade foi de 0,21 JC (0,08-0,45 JC). Observou-se uma clara separação de dois grupos, sendo V. gardneriana a mais isolada das quatro espécies, e V. capitata e V. megapotamica mais próxima geneticamente entre si. A atividade acaricida dos quatro óleos também foi avaliada por meio de ensaios de toxicidade e repelência contra o àcaro-da-necrose. O óleo essencial de V. gardneriana mostrou atividade acaricida ao A. guerreronis com uma CL50 de 0,85 mg.mL-1, enquanto que os óleos de V. capitata, V. megapotamica e V. rufecens não foram tóxicos para esta praga até 2,3 mg.ml-1, quando testados através do bioensaio de toxicidade. Em geral, os óleos essenciais destilados a partir das espécies de Vitex repeliram o A. guerreronis após 24 horas a uma concentração de 1.8 mg.mL-1 utilizando abamectina como controle no ensaio de repelência disco de duas escolha, no entanto, o óleo essencial de V. gardneriana apresentou atividade acaricida estatisticamente significativa frente ao ácaro-da-necrose-do-coqueiro. Apresentando-se como potencial candidato para o desenvolvimento de um produto acaricida. São Cristóvão, SE

The use of plants for therapeutic purposes is one of the oldest forms of medical practice of humankind. Isolated plant secondary metabolites have contributed significantly to the development of new drugs in recent years. Essential oils, vegetables present, are complex mixtures containing several dozen substances with varied chemical composition and various therapeutic properties. The main objective was to contribute to the scientific knowledge of plant species of the Caatinga with therapeutic potential for development of possible biotechnological products. Were chemically characterized by Nuclear Magnetic Resonance Spectroscopy (NMR) 1H and 13C one and two-dimensional, fixed and volatile secondary metabolites of Vitex gardneriana and volatile secondary metabolites of Croton piauhiensis. It was identified and quantified it is twelve (12) compounds of the essential oil of V. gardneriana, with a predominance of (66.34%) of sesquiterpenes. They were identified and quantified 21 (twenty-one) essential oil compounds from C. piauhiensis, with a predominance of (42.63%) of sesquiterpenes. Was isolated nine (9) fixed constituents V. gardneriana. From the shell VGC (I), a mixture of ursolic acid and oleanolic acid. From the wood: VGL (I) Synthesis of vanillin; VGL (II) p-hydroxy-benzoic acid; VGL (III) 4-hydroxy-3-methoxybenzoate p-hydroxy-benzoic acid (unpublished literature); VGL (IV) acid 2α, 3α, 19α-trihidroxiursan-12-en-28-oic acid and VGL (V) 3-O-β-D-glicopiranosilsitosterol (unprecedented in the literature). From the root: VGR (I) acid protocatechuic; VGR (II) 3-O-β-D-glicopiranosilsitosterol and VGR (III) a mixture of β-sitosterol and stigmasterol. The essential oils and five (5) Secondary metabolites were first tested by checking the antimicrobial activity in the planktonic and biofilm forms, was also checked the antioxidant potential using four different methods. For this purpose, the minimum inhibitory concentration experiments, were conducted, by microdilution technique (MIC) and checked the minimum bactericidal concentration (MBC). As well, as experiments for evaluating the inhibition of the development of biofilm formation by Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 10145. For this action, the techniques by crystal violet staining and colony forming units were performed. Statistical tests (p

O extrato metanólico das cascas do caule de Vitex gardneriana Schauer forneceu o ecdisteróide, 20-hidroxi-ecdisona e o iridóide glicosilado, aucubina. As estruturas foram caracterizadas por métodos químicos e espectroscópicos. The methanolic extract of the stem bark of Vitex gardneriana Schauer afforded the ecdysteroid, 20-hydroxy-ecdysone and the iridoid glycoside, aucubin. Their structures were established on the basis of chemical and spectroscopic studies.