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Braga, Portugal

Sousa R.M.O.F.,University of Minho | Rosa J.S.,University of The Azores | Silva C.A.,University of Minho | Almeida M.T.M.,University of Minho | And 5 more authors.
Journal of Pest Science

Plant-based products, namely essential oils (EOs), are environmentally friendly alternatives for the control of disease vectors, hosts and/or parasites. Here, we studied the general toxicity and biopesticidal potential of EOs and phenylpropanoids from Foeniculum vulgare var. vulgare (bitter fennel), a perennial plant well adapted to temperate climates. EO/compound toxicity was tested against a freshwater snail and potential intermediate host of Fasciola hepatica (Radix peregra), a mosquito and former European malaria vector (Anopheles atroparvus) and one of the most damaging plant-parasitic nematodes, the root-knot nematode (Meloidogyne javanica). Lethal concentrations (LC50; LC90) of EOs (infrutescences/stems with leaves) and compounds were calculated by probit analysis. All displayed noteworthy activity against R. peregra adults (LC50 21–39 µg ml−1) and A. atroparvus larvae (LC50 16–56 µg ml−1). trans-Anethole revealed acute nematicidal activity after 24 and 48 h (LC50 310 and 249 µg ml−1, respectively), and estragole (1,000 µg ml−1) showed some effectiveness against M. javanica hatching and juveniles after 15 days. Plant and EO yields were determined to evaluate the bitter fennel productivity. The chemical composition of the EOs was analyzed by gas chromatography coupled to mass spectrometry. EOs extracted from whole plants, infrutescences and stems with leaves were characterized by estragole-dominant profiles (28–65 %), considerable amounts of phellandrene (10–34 %) and fenchone (6–16 %), and minor trans-anethole contents (1–4 %). Although additional toxicological studies against nontarget organisms are required, our study demonstrates that bitter fennel is a productive source of molluscicides and larvicides, and thus a potential sustainable biological agent to control particular host species, namely freshwater snails and mosquitoes. © 2014, Springer-Verlag Berlin Heidelberg. Source

Guedes A.P.,University of Minho | Franklin G.,University of Minho | Fernandes-Ferreira M.,University of Minho | Fernandes-Ferreira M.,University of Porto | Fernandes-Ferreira M.,MAPPROD Lda
Phytochemistry Reviews

Phytochemical composition of Hypericum genus has been investigated for many years. In the recent past, studies on the essential oils (EO) of this genus have been progressing and many of them have reported interesting biological activities. Variations in the EO composition of Hypericum species influenced by seasonal variation, geographic distribution, phenological cycle and type of the organ in which EO are produced and/or accumulated have also been reported. Although many reviews attributed to the characterization as well as biological activities of H. perforatum crude extracts have been published, no review has been published on the EO composition and biological activities of Hypericum species until recently (Crockett in Nat Prod Commun 5(9):1493-1506, 2010; Bertoli et al. in Global Sci Books 5:29-47, 2011). In this article, we summarize and update information regarding the composition and biological activities of Hypericum species EO. Based on experimental work carried out in our laboratory we also mention possible biotechnology approaches envisaging EO improvement of some species of the genus. © Springer Science+Business Media B.V. 2011. Source

Ferreira P.,University of Minho | Cardoso T.,University of Minho | Ferreira F.,University of Minho | Fernandes-Ferreira M.,Center for the Research and Technology of Agro Environmental and Biological science | And 4 more authors.
FEMS Yeast Research

Mentha piperita (MP), also known as peppermint, is an aromatic and medicinal plant widely used in the food industry, perfumery and cosmetic, pharmacy and traditional medicine. Its essential oil (EO) displays antimicrobial activity against a range of bacteria and fungi. In this study, we found that MP EO lethal cytotoxicity is associated with increased levels of intracellular reactive oxygen species, mitochondrial fragmentation and chromatin condensation, without loss of the plasma membrane integrity, indicative of an apoptotic process. Overexpression of cytosolic catalase and superoxide dismutases reverted the lethal effects of the EO and of its major component menthol. Conversely, deficiency in Sod1p (cytosolic copper-zinc-superoxide dismutase) greatly increased sensitivity to both agents, but deficiency in Sod2p (mitochondrial manganese superoxide dismutase) only induced sensitivity under respiratory growth conditions. Mentha piperita EO increased the frequency of respiratory deficient mutants indicative of damage to the mitochondrial genome, although increase in mitochondrial thiol oxidation does not seem to be involved in the EO toxicity. Essential oil from Mentha piperata induces both cytosolic and mitochondrial ROS-mediated damage in Saccharomyces cerevisiae, resulting in apoptotic cell death that can be reverted by increased expression of Sod1p, Sod2p and Ctt1p. © 2014 Federation of European Microbiological Societies. Source

Rainha N.,University of The Azores | Lima E.,University of The Azores | Baptista J.,University of The Azores | Fernandes-Ferreira M.,Center for the Research and Technology of Agro Environmental and Biological science | And 2 more authors.
Natural Product Research

This study reports the first quantification study of pseudohypericin (PsHyp) and hypericin (Hyp) in Hypericum undulatum Schousb. ex Willd in vitro cultures developed by a Portuguese company. Both compounds were quantified by high-performance liquid chromatography and their levels were compared with those in commercial samples of Hypericum perforatum. PsHyp was found to be the major naphthodianthrone of H. undulatum, with an average ratio of 3.73:1 compared to Hyp. Significant statistical differences were found between the content of Hyp and PsHyp in H. undulatum regenerated shoots compared to in vivo samples. The mean concentration of total Hyps varied from 178.41 to 358.93 g g-1 dry extract in H. undulatum regenerated shoots, which is on average two to three times less than naphthodianthrone levels found in H. undulatum in vivo and H. perforatum commercial samples. However, none of the analysed samples presented the levels of Hyps required by the European and United States Pharmacopoeias. © 2013 Taylor & Francis. Source

Sousa R.M.O.F.,University of Minho | Rosa J.S.,University of The Azores | Oliveira L.,University of The Azores | Cunha A.,University of Minho | And 3 more authors.
Journal of Agricultural and Food Chemistry

Essential oils (EOs) from four Apiaceae species and 11 pure compounds were evaluated for their antifeedant, growth inhibitory, and insecticidal activities against Pseudaletia unipuncta (Lepidoptera: Noctuidae) fourth-instar larvae. EOs from Foeniculum vulgare subsp. vulgare var. vulgare, Anethum graveolens, Petroselinum crispum, and Cuminum cyminum were characterized by gas-chromatography (GC) and mass spectrometry. Anti-insect activity varied according to plant specie/composition, type, and exposure period. EOs from P. crispum and A. graveolens fruits, trans-anethole and cuminaldehyde, exerted acute effects on larvae feeding and growth (FDI and GI > 70%). A. graveolens, C. cyminum, and F. vulgare EOs and some of their constituents were effective by fumigation (≥80%). Satisfactory contact toxicities (>70%) were observed for five compounds and all EOs, except F. vulgare EOs, when tested by the filter paper impregnation method. For the most active EOs/compounds, dose-dependent toxicity was determined and inverse relationships of LC50 with time were established. © 2013 American Chemical Society. Source

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