The chemical composition of the front gland of termites has been studied for over 40 years. The genus Nasutitermes, considered the most evolved of the Termitidae family, has a peculiarity that sets it apart from the others: a caste of soldiers that carry a terpenic mixture used in defense. This secretion is formed by mono, sesqui and diterpenes from trinervitane, kempane and rippertane skeletons, only found in termites. This article sought to review the scientific literature and contribute to the knowledge on the chemical composition of the secretion of the Nasutitermes soldiers from the interesting aspects of its behavior.

Resumo Os recentes sinais de recuperação da flora nativa e endêmica da Ilha da Trindade, Brasil, são atribuídos à erradicação de vertebrados introduzidos no século XVIII. Três séculos de devastação resultaram no desaparecimento de espécies vegetais endêmicas e na redução drástica da cobertura florestal e das populações de aves marinhas. Em 2005 a Marinha do Brasil conclui a erradicação das cabras ferais, resultando no início da expansão da cobertura vegetal em áreas previamente nuas. Os únicos vertebrados invasores remanescentes são os camundongos. Esse fato representa um marco na história natural de Trindade e deve incentivar novos trabalhos de conservação na ilha.

Abstract The recent signs of recovery of the native and endemic flora of Trindade Island, Brazil, are attributed to the eradication of vertebrates which were introduced on the 18th Century. Three centuries of devastation lead to the disappearance of endemic plant species and to a drastic reduction of vegetation cover and sea bird populations. In 2005 the Brazilian Navy concluded the eradication of feral goats, resulting in the early expansion of vegetation cover on previously barren areas. The only remaining invasive vertebrates are the house mice. This fact represents a milestone in the natural history of Trindade and shall encourage new conservation research on the Island.

A composição química dos óleos essenciais das folhas e flores de Hyptis passerina Mart., uma espécie rara do cerrado brasileiro, está sendo descrita pela primeira vez. A análise por CG-EM revelou sesquiterpenos como constituintes majoritários. β-epi-acorenol (35.7% e 32.8%, respectivamente no óleo essencial das folhas e flores) foi isolado e identificado por RMN uni e bidimensionais. O óleo das flores apresentou maior concentração de monoterpenos (hidrocarbonetos e oxigenados), enquanto que o óleo das folhas foi mais rico em diterpenos. O aroma dos óleos foi investigado por análise olfatométrica direta e por CG-EM-O. Foi observado, para ambos os óleos, aroma herbáceo, com o óleo das folhas contendo nuances aromáticas de verde, cozido e madeiroso, lembrando chá, enquanto o óleo das flores apresentou aspectos de aroma condimentado, madeiroso e mentolado. β-epi-acorenol, espatulenol, β-cariofileno e óxido de cariofileno mostraram-se relevantes para a atividade odorífera dos óleos, bem como, constituintes minoritários como o linalol. A atividade antimicrobiana dos óleos foi investigada pelos métodos de difusão em disco de agar e bioautografia de contato contra bactérias Gram-positivas, negativas e fungos. Os óleos apresentaram-se ativos contra os microorganismos com nível de inibição significativo.

The chemical profile of the essential oils obtained from the leaves and flowers of Hyptis passerina Mart., a rare species of the Brazilian Cerrado, has been determined for the first time. Analyses by GC-MS showed sesquiterpenes as major compounds. β-epi-acorenol (35.7% and 32.8%, respectively from leaf and flower essential oils), was isolated and identified by 1D and 2D NMR. The flower-derived oil presented a higher concentration of hydrocarbon and oxygenated monoterpenes, while the leaf-oil was richer in diterpenes. The global odour impressions of both oils were given by direct analysis and GC-MS-O and were characterized as herbaceous with tea notes, and green, cooked and woody impressions for leaf-oil; herbaceous, with spicy, woody and minty notes for flower-oil. β-epi-acorenol, spathulenol, β-caryophyllene, and caryophyllene oxide were relevant for the odour-activity of both oils, as well as minor constituents, such as linalool. The antimicrobial activity was investigated by means of agar diffusion disc method and contact bioautography, against Gram-positive and negative bacteria and yeast. Both oils presented to be bioactive against the tested microorganisms with significant inhibition level.

As flores de Zizyphus mauritiana Lam. (Rhamnaceae) exalam um forte odor fecal, e sua análise por micro-extração em fase sólida (SPME) associada a cromatografia gasosa- espectrometria de massas (CG-EM), co-injeção de padrões e índices de retenção revelou o benzaldeído como constituinte majoritário. Foram observados ainda benzenóides, ácidos carboxílicos, aldeídos, hidrocarbonetos alifáticos e monoterpenóides. A avaliação olfatométrica do SPME realizada por CG- olfatometria em sniffing port indicou o escatol (3-metil-indol) como o responsável pelo odor fecal das flores e a vanilina pelo seu odor adocicado.

When in blossom, jujube (Zizyphus mauritiana Lam., Rhamnaceae) emanates a strong fecal odor. The substances responsible for this scent were analysed by headspace solid-phase microextraction and gas chromatography-mass spectrometry (SPME-GC-MS) associated to standard co-injection and retention indexes, which showed benzaldehyde as major constituent. Minor benzenoids, aliphatic carboxylic acids, aldehydes, hydrocarbons and oxygenated monoterpenes were also observed. Olfactometric evaluation of the SPME using GC-sniffing port indicated skatole (3-methyl-indole) as responsible for the fecal odor and vanillin for the sweety odor.

The volatile constituents obtained from a static cryogenic headspace of Caesalpinia echinata Lam. (Leguminosae) showed E-beta-ocimene as the major compound (57.2%), beside other monoterpenes, C6 derivatives like n-hexanal and (E)-2-hexenal and nitrogen compounds such as indole and methyl anthranilate. From the essential oil of the leaves obtained by hydrodistillation in a Clevenger apparatus, (E)-3-hexen-1-ol was identified as the major constituent while phenolic compounds were the most representative class of secondary metabolites.