Botanical extracts: alternative control for silverleaf whitefly management in tomato

Bemisia tabaci (Hemiptera: Aleyrodidae) biotype B is one of the most limiting pests of tomato crops in the world. Tomato yield is currently dependent on the use of pesticides, which are problematic to farmers, consumers and the environment. A promising alternative to reduce the harmful effects caused by the indiscriminated use of synthetic insecticides is the use of insecticides of botanical origin. This study aimed to evaluate the effect of 3% (w/v) aqueous extracts from different structures of thirteen botanical species on the behavior of B. tabaci biotype B adults, as well as insecticidal activity of such aqueous extracts on B. tabaci eggs, nymphs, and adults infesting tomato plants. A distilled water solution was used as a negative control, and thiamethoxam insecticide (18 g/100 L of water) as a positive control. Leaf extract of Toona ciliata was observed to have the most efficient inhibitory effect in tests of extracts on whitefly behavior. Furthermore, the use of leaf extract of Toona ciliata led to the most drastic reduction in the number of adults and eggs on tomato leaflets. Leaf extract of Piper aduncum led to the greatest observed ovicidal effect (78.00% of non-hatched nymphs); however it was not effective against nymphs and adults. The leaf extracts of Trichilia pallida, Trichilia casaretti, and Toona ciliata showed the highest control indexes (67.9, 60.3, and 55.1%, respectively). For adults mortality, T. pallida was the most effective (72.8%). Our results indicate that application of extracts of T. pallida, T. ciliata, and T. casaretti are promising strategies to manage B. tabaci biotype B on tomato.

Composition and antifungal activity against Candida albicans, C. parapsilopisis, Candida krusei and Cryptococcus neoformans of essential oils from leaves of Piper and Peperomia species

This study was addressed to investigate the composition and antifungal activity of essential oils from leaves of Piperaceae species (Piper aduncum, Piper amalago, Piper cernuum, Piper diospyrifolium, Piper crassinervium, Piper gaudichaudianum, Piper solmsianum, Piper regnellii, Piper tuberculatum, Piper umbelata and Peperomia obtusifolia) against Candida albicans, C. parapsilosis, C. krusei and Cryptococcus neoformans. The essential oils from P. aduncum, P. gaudichaudianum and P. solmsianum showed the highest antifungal activity against Cryptococcus neoformans with the MIC of 62.5, 62.5 and 3.9 mg.mL-1, respectively. The oil from P. gaudichaudianum showed activity against C. krusei with MIC of 31.25 mg.mL-1.

Natural chromenes and chromene derivatives as potential anti-trypanosomal agents

The aim of the study was to investigate the anti-trypanocidal activities of natural chromene and chromene derivatives. Five chromenes were isolated from Piper gaudichaudianum and P. aduncum, and a further seven derivatives were prepared using standard reduction, methylation and acetylation procedures. These compounds were assayed in vitro against epimastigote forms of Trypanosoma cruzi, the causative agent of Chagas disease. The results showed that the most of the compounds, especially those possessing electron-donating groups as substituents on the aromatic ring, showed potent trypanocidal activity. The most active compound, [(2S)-methyl-2-methyl-8-(3″-methylbut-2″-enyl)-2- (4′-methylpent-3′-enyl)-2H-chromene-6-carboxylate], was almost four times more potent than benznidazole (the positive control) and showed an IC 50 of 2.82 μM. The results reveal that chromenes exhibit significant anti-trypanocidal activities and indicate that this class of natural product should be considered further in the development of new and more potent drugs for use in the treatment of Chagas disease. © 2008 Pharmaceutical Society of Japan.

Trypanosoma cruzi: Evaluation of (-)-cubebin derivatives activity in the messenger RNAs processing

No fully effective treatment has been developed since the discovery of Chagas' disease. Since drug-resistant Trypanosoma cruzi strains are occurring and the current therapy is effective in the acute phase but with various adverse side effects, more studies are needed to characterize the susceptibility of T. cruzi to new drugs. Pre-mRNA maturation in trypanosomatids occurs through a process called trans-splicing, which is unusual RNA processing reaction, and it implies the processing of polycistronic transcription units into individual mRNAs; a short transcript spliced leader (SL RNA) is trans-spliced to the acceptor pre-mRNA, giving origin to the mature mRNA. Cubebin derivatives seem to provide treatments with less collateral effects than benznidazole and showed similar or better trypanocidal activities than benznidazole. Therefore, the cubebin derivatives ((-)-6,6′-dinitrohinokinin (DNH) and (-)-hinokinin (HQ)) interference in the mRNA processing was evaluated using T. cruzi permeable cells (Y and BOL (Bolivia) strains) following by RNase protection reaction. These substances seem to intervene in any step of the RNA transcription, promoting alterations in the RNA synthesis, even though the RNA processing mechanism still occurs. Furthermore, HQ presented better activity against the parasites than DNH, meaning that BOL strain seems to be more resistant than Y. © 2011 Springer-Verlag.

Fungos endofíticos: Uma fonte inexplorada e sustentável de novos e bioativos produtos naturais

Endophytic fungi are a rich source of new and biologically active natural products. They colonize a relatively unexplored ecological habitat and their secondary metabolism is particularly active, presumably due to metabolic interactions with their hosts. In the course of our continuing investigations for new and bioactive compounds from endophytic fungi from brazilian flora Alibertia macrophylla, Caseria sylvestris, Ocotea corymbosa, Cassia spectabilis, Piper aduncum, Cryptocaria mandioccana, Xylopia aromatica and Palicourea marcgravii were investigated. Forty two natural products were isolated and their structures were established on the basis of comprehensive spectral analysis, mainly using 1D and 2D NMR experiments. The compounds were tested in their antifungal, antioxidant, anticholinesterasic and anticancer activities.

Avaliação da capacidade antioxidante de extratos vegetais de plantas brasileiras e sua contribuição ao estudo de inibição da enzima mieloperoxidase

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Frugivoria e germinação de sementes após passagem pelo sistema digestivo de masupiais em floresta estacional semidecidual

Pós-graduação em Ciências Biológicas (Botânica) - IBB

Controle de Guignardia citricarpa e Penicillium digitatum em laranja com óleos essenciais e agentes de biocontrole

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Frugivory and the effects of ingestion by bats on the seed germination of three pioneering plants

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Interindividual variations in fruit preferences of the yellow-shouldered bat Sturnira lilium (Chiroptera: Phyllostomidae) in a cafeteria experiment

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Riqueza, abundância e dieta de morcegos (Chiroptera) em floresta de eucaliptos

Os quirópteros apresentam grande diversidade e variação de hábitos alimentares, desempenhando um importante papel ecológico, se destacando pela dispersão de sementes que auxilia na conservação e restauração de ambientes degradados. Em caso de monoculturas, espera-se que reflorestamentos mais antigos com sub-bosque bem desenvolvido abriguem comunidades com maior diversidade de espécies se comparados a reflorestamentos utilizados para fins comerciais. O objetivo deste estudo é conhecer a riqueza, abundância e diversidade de morcegos e a dieta das espécies frugívoras em uma área refloresta por Eucalyptus spp., a Floresta Estadual Edmundo Navarro de Andrade localizada em Rio Claro - SP. As capturas ocorreram entre maio de 2014 e 2015, utilizando redes de neblina e um esforço amostral de 9072 m².h. As fezes encontradas foram coletadas, identificadas usando-se uma coleção de referência em laboratório e associadas às espécies de morcegos. Foi realizado um teste de germinação com Piper amalago para verificar o efeito da passagem de sementes pelo trato digestivo dos morcegos. São apresentados dados de dominância, constância, estimativas de riqueza (Chao1, Jackknife2) e diversidade (Shannon-Wiener) de morcegos, assim como índice de valor de importância de interação (Murray) para plantas e morcegos e a velocidade e a porcentagem germinativa de sementes de Piper amalago. Foram capturados 86 indivíduos de nove espécies de quirópteros pertencentes a duas famílias. As espécies encontradas são, em sua maioria, generalistas, sendo a mais abundante Artibeus lituratus, seguido de Carollia perspicillatta, esta se alimentou de 10 espécies diferentes de plantas, tendo o maior valor no índice de importância, enquanto Piper aduncum foi a planta consumida pelo maior número de morcegos na área de estudo. As espécies de plantas consumidas são principalmente pioneiras como Piperaceae e Solanaceae, que contribuem para a...

Clastogenicity of Piper cubeba (Piperaceae) seed extract in an in vivo mammalian cell system

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Geranylation of benzoic acid derivatives by enzymatic extracts from Piper crassinervium (Piperaceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Toxicity of extracts and isobutyl amides from Piper tuberculatum: potent compounds with potential for the control of the velvetbean caterpillar, Anticarsia gemmatalis

The isobutyl amides pellitorine (compound 1) and 4,5-dihydropiperlonguminine (compound 2) were extracted from the seeds of Piper tuberculatum Jacq. (Piperaceae) in yields of 6.10 and 4.45% respectively. The acute toxicities to the velvetbean caterpillar, Anticarsia gemmatalis (Hubner) (Lepidoptera: Noctuidae), of extracts of seeds, leaves and stems of P. tuberculatum, and of compounds 1 and 2, were evaluated by means of contact bioassays. The extracts caused 80% mortality when doses higher than 800.00 mu g insect(-1) of extract of seeds, leaves and stems were administered to the velvetbean caterpillars. Compounds I and 2 showed 100% mortality at doses of 200 and 700 mu g insect(-1) respectively. The LD50 and LD90 values were respectively 31.3 and 104.5 mu g insect(-1) for compound 1, and 122.3 and 381.0 mu g insect(-1) for compound 2. The potential value of extracts and amides derived from P. tuberculatum as efficient insecticides against velvetbean caterpillars is discussed. (c) 2007 Society of Chemical Industry.

Antifungal amide from leaves of Piper hispidum

Bioactivity-guided fractionation of a CH2Cl2 extract from leaves of Piper hispidum (Piperaceae) yielded a new pyrrolidine amide, N-[7-(3',4'-methylenedioxyphenyl)-2(Z),4(Z)-heptadienoyl] pyrrolidine 1, in addition to two known amides N-[5-(3',4'-methylenedioxyphenyl)-2(E)-pentadienoyl]pyrrolidine and N-[2-(3',4'-methylenedioxy-6'-methoxyphenyl)-2(Z)-propenoyl]pyrrolidine. The structure of compound 1 was elucidated by interpretation of spectral data, including ES-MS. Compound 1 showed antifungal activity against Cladosporium sphaerospermum.