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Anna CC Aguiar Ananda C Cunha Isabela Penna Ceravolo Regina A Correia Gon?alves Arildo JB Oliveira Antoniana Ursine Krettli 《Memórias do Instituto Oswaldo Cruz》2015,110(7):906-913
Several species of Aspidosperma plants are used to treat diseases in
the tropics, including Aspidosperma ramiflorum, which acts against
leishmaniasis, an activity that is experimentally confirmed. The species, known as
guatambu-yellow, yellow peroba,
coffee-peroba andmatiambu, grows in the Atlantic
Forest of Brazil in the South to the Southeast regions. Through a guided
biofractionation of A. ramiflorum extracts, the plant activity
against Plasmodium falciparum was evaluated in vitro for toxicity
towards human hepatoma G2 cells, normal monkey kidney cells and nonimmortalised human
monocytes isolated from peripheral blood. Six of the seven extracts tested were
active at low doses (half-maximal drug inhibitory concentration < 3.8 µg/mL); the
aqueous extract was inactive. Overall, the plant extracts and the purified compounds
displayed low toxicity in vitro. A nonsoluble extract fraction and one purified
alkaloid isositsirikine (compound 5) displayed high selectivity indexes (SI) (= 56
and 113, respectively), whereas compounds 2 and 3 were toxic (SI < 10). The
structure, activity and low toxicity of isositsirikine in vitro are described here
for the first time in A. ramiflorum, but only the neutral and
precipitate plant fractions were tested for activity, which caused up to 53%
parasitaemia inhibition of Plasmodium berghei in mice with
blood-induced malaria. This plant species is likely to be useful in the further
development of an antimalarial drug, but its pharmacological evaluation is still
required. 相似文献
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Rogério Aparecido Minini dos Santos Adriano Valim Reis Eduardo Jorge Pilau Carla Porto José Eduardo Gonçalves Arildo José Braz de Oliveira 《Biocatalysis and Biotransformation》2020,38(4):315-323
AbstractThe development of more efficient and environmentally friendly analytical methods represents a current focus for the fine chemical industry. In particular, microscale methodologies that are free of solvents/reagents. The headspace-GC/MS (HS-GC) methodology was employed in this study as a tool for monitoring a biocatalysed reaction of (4S)-(+)-carvone using Phoma sp., a filamentous fungus from human skin. Biocatalysis provides some advantages, such as high efficiency, high degrees of regioselectivity, chemoselectivity, and enantioselectivity. In order to optimize the small scale biocatalytic reaction of the (4S)-(+)-carvone by the filamentous fungus Phoma sp. was used headspace GC/MS methodology, factorial design of experiments and the response surface methodology (RSM) was performed using the biomass of the fungus, substrate mass and pH as parameters. It was observed that for all reactions conditions tested, forming the products (1?R,4S)-dihydrocarvone and (1S,4S)-dihydrocarvone. The most influential factor was pH, with the highest conversion rate (>95%) and diastereomeric excess (d.e.) (>80%) obtained at pH 5.0. Thus, it was demonstrated that human skin Phoma sp. fungus showed significant bioreduction activity and that headspace GC/MS is an efficient approach for real-time monitoring the biocatalysed reactions. 相似文献
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Arildo S. Dias Karin dos Santos Flavio Antonio Maës dos Santos Fernando R. Martins 《Plant Ecology》2017,218(2):119-125
Intense competition with lianas (wood climbers) can limit tree growth, reproduction, and survival. However, the negative effects of liana loads on tree allometry have not yet been addressed. We investigated the hypothesis that liana loading on tree crown alters tree’s allometry, expressed through slenderness (height–diameter ratio). The relationship between trunk slenderness and percentage of tree crown covered by lianas was investigated for 12 tree species from 10 fragments of the Semideciduous Seasonal Forest in Southeastern Brazil. We also tested whether the relationship between slenderness and wood density differ between trees without lianas and trees heavily infested. Liana loads significantly altered tree allometry by decreasing slenderness, even when lianas covered less than 25% of tree crown. Heavy-wood species decreased their trunk slenderness in a greater ratio than light-wood species. Our findings indicate that liana infestation shifts tree allometry, and these effects are stronger on heavy-wood tree species. 相似文献
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Rogério Aparecido Minini dos Santos Felipe de Oliveira Souza Eduardo Jorge Pilau Carla Porto José Eduardo Gonçalves Arildo José Braz de Oliveira 《Biocatalysis and Biotransformation》2018,36(5):396-400
The synthesis of optically pure compounds is increasingly in demand among the pharmaceutical, fine chemical and agro-food industries, while the importance of chirality in the activity and biological properties of many compounds has previously been established. The aim of the present study was therefore to evaluate the biotransformation capacities of (+)-carvone and (?)-carvone using the fungi Scolecobasidium sp, three lines of Cladosporium sp, Phoma sp, Aureobasidium sp and Epicoccum sp, all obtained from human skin. The seven fungi evaluated were capable of hydrogenating the activated alkene, followed by the reduction of ketone to chiral alcohol, with conversions between 9.5 and 100%, and with diastereomer excess (d.e.) of over 89% of dihydrocarveol when (+)-carvone was used as a substrate. These results demonstrate that the filamentous fungi of human skin are potential biocatalytic tools for obtaining chiral alcohols. 相似文献
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Cunha Ade C Chierrito TP Machado GM Leon LL da Silva CC Tanaka JC de Souza LM Gon?alves RA de Oliveira AJ 《Phytomedicine》2012,19(5):413-417
The present study was designated to evaluate semi-quantitative antileishmanial activity of alkaloidal extracts that were obtained from 1g of different parts of Aspidosperma ramiflorum (leaves, roots, seeds, and stem barks). Alkaloidal extracts of barks and leaves presented a good activity against the extracellular form (promastigotes) of Leishmania (L.) amazonensis. It is known that compounds responsible for the antileishmanial activity in the alkaloidal extracts from A. ramiflorum are the monoterpenoid indole alkaloids ramiflorine A and ramiflorine B, therefore extracts obtained from different plant parts were analyzed by electrospray ionization mass spectrometry (ESI-MS) in order to evidence the presence of these bioactive alkaloids. Based on these findings, alkaloidal extract from leaves was fractionated on preparative thin-layer chromatography in a bioassay-guided fractionation affording individual purified ramiflorines A and B. Both ramiflorines A and B showed significant activity against Leishmania (L.) amazonensis (LD(50) values of 18.5±6.5μg/ml and 12.63±5.52μg/ml, respectively). Our results are showing that alkaloidal extract from leaves is a promising alternative to the use of stem barks from A. ramiflorum. 相似文献
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Rafael Valim Reis Ana Paula Patrão Luis Borges Talita Perez Cantuaria Chierrito Eliezer Rodrigues de Souto Lauro Mera de Souza Marcello Iacomini Arildo José Braz de Oliveira Regina Aparecida Correia Gonçalves 《Plant Cell, Tissue and Organ Culture》2011,106(2):329-335
Cultures of adventitious roots of Stevia rebaudiana (Bert.) Bertoni were performed in a roller bottle system for the production of both primary and secondary metabolites. Adventitious
roots were induced from 1-cm-long root tip explants derived from in vitro regenerated plantlets on solid Murashige and Skoog
(MS 1962) media supplemented with 10.7 μM of α-naphthaleneacetic acid. These cultures were successfully maintained in the
same medium for 6 months with regular subcultures after 4 weeks. Thereafter, the roots were cut into 1.0- to 1.5-cm-long segments
and transferred to the roller bottle system containing a fresh root tissue culture on liquid MS medium supplemented with 10.7 μM
NAA. The apparatus consisted of a flask rolling system adjusted to 4g, and 3° of flask inclination. The roots were allowed to grow in the absence of light for adaptation and adventitious root
formation. The best conditions for cultivation were investigated, considering culture volume (25 ml), culture period (4 weeks),
salt concentrations in the nutrient medium (33%) and optimal initial inoculum (0.2 g) of S. rebaudiana roots. These results could give important information on how to improve the development of adventitious roots of S. rebaudiana for the production of primary and secondary metabolites. 相似文献
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Ferreira IC Lonardoni MV Machado GM Leon LL Gobbi Filho L Pinto LH de Oliveira AJ 《Memórias do Instituto Oswaldo Cruz》2004,99(3):325-327
Infections due to protozoa of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The drugs of choice for the treatment of leishmaniasis are the pentavalent antimonials (SbV), which present renal and cardiac toxicity. Besides, the precise chemical structure and mechanism of action of these drugs are unknown up to date. In order to find new drugs against leishmaniasis, we have been studying extracts of Brazilian trees. In the present study, we have evaluated the effectiveness of an alkaloid extract of Aspidosperma ramiflorum Muell. Arg. (Apocynaceae), against the extracellular forms promastigotes of L. (L.) amazonensis and L. (V.) braziliensis. The alkaloid extract of A. ramiflorum was much more effective against L. (L.) amazonensis (LD50 < 47 microg/ml) than L. (V.) braziliensis. Based on these in vitro results against L. (L.) amazonensis new studies should be made to find the compounds with anti-leishmanial activity. 相似文献
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