Navegando por Autor "JARDIM, Iselino Nogueira"

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Acesso aberto (Open Access)
Essential oils and its components in the control of Meloidogyne incognita in soybeans and tomatoes
(Universidade Federal de Lavras, 2017-03-31) JARDIM, Iselino Nogueira; SOUZA, Paulo Estevão de; http://lattes.cnpq.br/2663805208279411
Essential oils derived from secondary plant metabolism may have activities against root-knot nematodes, Meloidogyne incognita. Because nematicides that are more efficient and less toxic to humans and the environment than those available are desirable to control this pathogen, this work aimed at studying the essential oil of Cinnamomum cassia and Allium sativum, which were described as active in vitro against the nematode Bursaphelenchus xylophilus. The essential oils of both species were obtained by hydrodistillation, initially dissolved in aqueous solution of Tween 80 at 0.01 g mL-1 and tested in vitro against M. incognita. At 62 μg mL-1 the oil emulsions were more active on eggs and second stage juveniles (J2) than Carbofuran at 173 μg mL-1. According to gas chromatography-mass spectrometry analysis, the major constituent of C. cassia is (E) -cinnamaldehyde (83.3%), while for garlic oil were diallyl trisulfide (66.7%) and diallyl disulfide (21.3%). These constituents explained the in vitro nematicidal activity of the essential oil of each plant species. The emulsion of the C. cassia (500 μg mL-1), E)-cinnamaldehyde (416 μg mL-1) and garlic (250 μg mL -1) reduced the number of galls and eggs in roots soybean and tomatoes to values statistically equal to those obtained with Carbofuran at 415 μg mL-1. Vapors from the essential oils and (E)-cinnamaldehyde were active as much as the basamid fumigant nematicide used in the in vitro assays against M. incognita. Infectivity and reproduction of M. incognita in soybean and tomato plants grown on substrate artificially infested with nematode eggs and treated with 0.2 mL (garlic), 1.0 mL (E)-cinnamaldehyde and 0.25 g of Basamid were statistically equal among themselves in reducing the nematode population. These results unequivocally proofs of the nematicidal activity of the essential oils and of the (E)-cinnamaldehyde substance against M. incognita, therefore, both oil (E)-cinnamaldehyde are very promising to the development of new fumigant nematicides for the control of nematodes in soybean and tomato plants.
Acesso aberto (Open Access)
A structure-activity relationship (SAR) study of neolignan compounds with anti-schistosomiasis activity
(2002-06) ALVES, Claudio Nahum; MACEDO, Luiz Guilherme Machado de; HONORIO, Kathia Maria; CAMARGO, Ademir João; SANTOS, Lourivaldo da Silva; JARDIM, Iselino Nogueira; BARATA, Lauro Euclides Soares; SILVA, Alberico Borges Ferreira da
A set of eighteen neolignan derivative compounds with anti-schistosomiasis activity was studied by using the quantum mechanical semi-empirical method PM3 and other theoretical methods in order to calculate selected molecular properties (variables or descriptors) to be correlated to their biological activities. Exploratory data analysis (principal component analysis, PCA, and hierarchical cluster analysis, HCA), discriminant analysis (DA) and the Kth nearest neighbor (KNN) method were employed for obtaining possible relationships between the calculated descriptors and the biological activities studied and predicting the anti-schistosomiasis activity of new compounds from a test set. The molecular descriptors responsible for the separation between active and inactive compounds were: hydration energy (HE), molecular refractivity (MR) and charge on the C19 carbon atom (Q19). These descriptors give information on the kind of interaction that can occur between the compounds and their respective biological receptor. The prediction study was done with a new set of ten derivative compounds by using the PCA, HCA, DA and KNN methods and only five of them were predicted as active against schistosomiasis.
Acesso aberto (Open Access)
Structure-activity relationship of compounds which are anti-schistosomiasis active
(1998-12) ALVES, Claudio Nahum; BARROSO, Lucia Pereira; SANTOS, Lourivaldo da Silva; JARDIM, Iselino Nogueira
The molecular orbital method AM1 was employed to calculate a set of molecular descriptors for twenty synthetic neolignan derivatives with anti-schistosomiasis activity. The pattern recognition method (principal component analysis PCA and cluster analysis CA and discriminant analysis methods) have been employed to obtain the relationship between the molecular descriptors and biological activity. The set of molecules was classified into two groups according to their degree of biological activity. These results allow us to rationally project new compounds, potential candidates for synthesis and biological evaluation.