Radical Scavenging Capacity of Piper arboreum and Piper tuberculatum (Piperaceae)

In the scope of our ongoing researchers on antioxidant compounds, twenty four extracts and fractions obtained from Piper arboreum Aublet and Piper tuberculatum Jacq. (Piperaceae) were screened for radical scavenging capacity (RSC) by using DPPH colorimetric assay. The strongest activity was found in ethyl acetate fractions from the leaves of P. arboreum IC(50) = 5.70 mu g/mL) and P. tuberculatum IC(50) = 8.40 mu g/mL). Hydromethanol fractions of the leaves of P. tuberculatum and P. arboreum showed moderate RSC, with values of IC(50) (mu g/mL) of 11.9 and 19.2, respectively. Additionally, a brief phytochemical study of the ethyl acetate fraction of P. arboreum leaves affording quercetin (1) and quercitrin (2), two flavonols with antioxidant activity previously described in the literature.

Atividade tripanocida de Piper arboreum e Piper tuberculatum (Piperaceae)

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

Radical Scavenging Capacity of Piper arboreum and Piper tuberculatum (Piperaceae)

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

Antimicrobial activity of Piper arboreum and Piper tuberculatum (Piperaceae) against opportunistic yeasts

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

Quantitative determination of anti-fungal and insecticide amides in adult plants, plantlets and callus from Piper tuberculatum by reverse-phase high-performance liquid chromatography

A rapid, sensitive and reliable reverse-phase HPLC method was used for the quantitative determination of the anti-fungal and insecticide amides, dihydropiplartine (1), piplartine (2), Delta(alpha,beta)-dihydropiperine (3) and pellitorine (4) in plants in natura, in plantlets in vitro and ex vitro, and in callus of Piper tuberculatum. Well-resolved peaks were obtained with good detection response and linearity in the range of 15.0-3000 mug/mL. The plants in natura contained compounds 1-4, the plantlets ex vitro and in vitro accumulated compounds 1-2 and 1-4, respectively, while only amide 4 was found in callus. Copyright (C) 2003 John Wiley Sons, Ltd.

Antifungal amides from Piper hispidum and Piper tuberculatum

Piper hispidum and Piper tuberculatum accumulate amides bearing isobutyl, pyrrolidine, dihydropyridone and piperidine moieties. The isolation and characterization of several representatives including two hitherto unreported amides were performed by chromatographic techniques and by analysis of spectroscopic data. The antifungal activity of each amide was determined by direct bioautography against Cladosporium sphaerospermum. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

Composition and antifungal activity of essential oils from Piper aduncum, Piper arboreum and Piper tuberculatum

The composition of essential oils from leaves, stems and fruits of Piper aduncum, P arboreum and P. tuberculatum was examined by means of GC-MS and alltifungal assay. There was a predominance of monoterpenes in P aduncum and P tuberculatum and of sesquiterpenes in P arboreum. P aduncum showed the richest essential oil composition, including linalool. The essential oils from fruits of P. aduncum and R tuberculatum showed the highest antifungal activity with the MIC of 10 mu g as determined against Cladosporium cladosponoides and C. sphaerospermum, respectively. This is the first report of the composition of essential oils from P. tuberculatum.

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 amides from Piper arboreum and Piper tuberculatum

In continuation of our study of the Piperaceae we have isolated several amides, mainly those bearing isobutyl, pyrrolidine, dihydropyridone and piperidine moieties. Bioactivity-guided fractionation of extracts from leaves of Piper arboreum yielded two new amides, N-[10-(13,14-methylenedioxyphenyl)-7(E),9(Z)-pentadienoyl]-pyrrolidine (1), arboreumine (2) together with the known compounds N-[10-(13,14-methylenedioxyphenyl)-7(E)-pentaenoyl]-pyrrolidine (3) and N-[10-(13,14-methylenedioxyphenyl)-7(L, 9(E)-pentadienoyl]-pyrrolidine (4). Catalytic hydrogenation of 3 yielded the amide iV-[10-(13,14-methylenedioxyphenyl)-pentanoyl]-pyrrolidine (5). We also have isolated six amides (6-11) and two antifungal cinnamoyl derivatives (12, 13) from seeds and leaves of Piper tuberculatum. Compounds 1-11 showed antifungal activity as determined by direct bioautography against Cladosporium sphaerospermum while compounds 3-4 and 6-13 also showed antifungal activity against C. cladosporioides. (C) 2002 Published by Elsevier B.V. Ltd.

Susceptibility of Apis mellifera (Hymenoptera: Apidae) to pellitorine, an amide isolated from Piper tuberculatum (Piperaceae)

The acute toxicity of pellitorine, an amide isolated from Piper tuberculatum (Piperaceae) which is studied as a biopesticide in European corner borer, was evaluated on larvae and newly emerged adults of honeybee Apis mellifera by means of contact and ingestion bioassays. Workers in the larval and adult phase were separated in groups, which received pellitorine in different concentrations. The larvae were maintained in their own original cells, receiving feeding and normal care from the nurses. The adults were confined in wooden cages with screens, receiving artificial diet made up of sugar and water (1:1). The concentrations of 40, 200, 1 000, 5 000 and 25 000 ng a.i./individual were obtained diluting pellitorine in 98% ethanol. LD10 values of 39.14, 36.16 and 13.79 ng a.i./insect were determined for larvae, for adults by ingestion and adults by contact, respectively. The honeybee larvae were shown to be highly susceptible to the amide pellitorine.

Extração e análise eletroforética em gel de poliacrilamida (SDS-PAGE) de proteínas totais de folhas e raízes de Piper tuberculatum

O Estado do Pará é o principal produtor brasileiro de pimenta-do-reino (Piper nigrum Link), entretanto a sua produção tem sido bastante afetada pela doença conhecida como fusariose. O Fusarium solani f. sp. piperis é o agente causador desta doença que afeta o sistema radicular da planta, causando o apodrecimento das raízes e a queda das folhas levando à morte da planta. Algumas piperáceas nativas da região amazônica, entre elas a espécie Piper tuberculatum Jacq., têm se mostrado resistentes à infecção pelo F. solani f. sp. piperis, e desta forma têm sido utilizadas em estudos de interação planta-patógeno. Neste trabalho foram avaliadas cinco condições de extração de proteínas com o objetivo de selecionar tampões adequados para a extração de proteínas totais de folhas e raízes de P. tuberculatum. Os tampões utilizados para a extração de proteínas de raízes e folhas foram: tampão salino, tampão sacarose, tampão glicerol, tampão uréia e tampão fosfato de sódio. As análises quantitativas mostraram que os tampões sacarose, glicerol e uréia foram mais eficientes na extração de proteínas de folhas e raízes. Análises de SDS-PAGE mostraram padrões diferenciados de bandas em extratos protéicos de folhas e raízes obtidos com os diferentes tampões. Os resultados obtidos neste trabalho contribuem para a identificação de tampões de extração adequados para a obtenção de amostras de proteínas totais em estudos de interação P. tuberculatum - F. solani f. sp. piperis.

Abordagens biossintéticas em piper tuberculatum auxiliada pela síntese de precursores fenilpropanoídicos

Pós-graduação em Química - IQ

Larvicidal activity of Piper tuberculatum on Spodoptera frugiperda (Lepidoptera: Noctuidae) under laboratory conditions

The larvicidal activity of the neotropical "matico" Piper tuberculatum was evaluated. The secondary compounds were extracted of leaves, stems and mature spikes with fruits and seeds from wild plants and in vitro plants of Piper tuberculatum. The acute toxicities to the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), of extracts of spikes with fruits and seeds and in vitro plants of P tuberculatum were evaluated by means of contact bioassays. Only CH2Cl2:MeOH (2:1) and EtOH extracts of mature spikes and CH2C12:MeOH (2:1) extract from in vitro plants showed significant levels of larval mortality. The CH2Cl2:MeOH (2:1) and EtOH extracts of mature spikes caused 90% mortality when doses of 0.1850 mg/mu L were applied to the S. frugiperda in 24 and 48 h of exposure, respectively. The CH2Cl2:MeOH (2:1) extract from in vitro plants caused 95% mortality when doses of 0.1850 mg/mu L were too applied in 48 h of exposure. The mature spikes test best results were: LD50 0.001 mg/mu L with EtOH and 0.007 mg/mu L with CH2Cl2:MeOH (2:1) and LD90 0.027 mg/mu L with EtOH and 0.103 mg/mu L with CH2Cl2:MeOH (2:1); and, in the case of in vitro plants, only CH2Cl2:MeOH (2:1) extract was: LD50 0.003 mg/mu L and LD90 0.060 mg/mu L. The potential value of extracts derived from P. tuberculatum as efficient insecticides against S.frugiperda is discussed.