7 research outputs found
Neoangiogênese de retalhos cutâneos em ratos tratados com óleo de copaíba
The aim of this work was to evaluate morphometric aspects of subdermic skin flap neoangiogenesis in rats treated with a 10% copaiba (Copaifera langsdorffii) oil ointment. The experiment design was a completely randomized, with three pharmacological resources. Ten replicates were used for each resource, and each animal was considered one experimental unit. Thirty Wistar rats were submitted to subdermic dorsal skin flap elevation and distributed into three groups: absolute control group, in which the animals did not receive any treatment; control group, in which the animals received topical treatment only with vehicle (glycerin and petroleum jelly), and treated group, in which the animals were treated daily with a 10% copaiba oil ointment. The rats were treated and observed for eight days after surgery. On the eighth day, the skin flap underwent a macroscopic analysis and fragments were collected from its cranial, medial and caudal portions for histopathological analysis. The morphometric analysis showed significant difference for proliferation of newly formed vessels in the middle and caudal portions of the skin flap in the treated group. Copaiba oil showed efficiency in the increase of neoangiogenesis of subdermic skin flaps in rats.O objetivo deste trabalho foi avaliar morfometricamente a neoangiogênese de retalhos cutâneos subdérmicos em ratos tratados com óleo de copaíba (Copaifera langsdorffii) em pomada a 10%. O delineamento experimental foi inteiramente casualizado, composto por três recursos farmacológicos. Foram utilizadas dez repetições para cada recurso, e cada animal foi considerado uma unidade experimental. Trinta ratos Wistar foram submetidos à elevação do retalho cutâneo dorsal subdérmico e distribuídos em três grupos: grupo controle absoluto, no qual os animais não receberam nenhum tratamento; grupo controle, no qual os animais receberam tratamento tópico diário com pomada com apenas veículo (glicerina e vaselina); e grupo tratado, no qual os animais foram tratados diariamente com óleo de copaíba em pomada a 10%. Os ratos foram tratados e observados por oito dias após o ato operatório. No oitavo dia de pós-operatório, realizou-se a análise macroscópica do retalho e foram coletados fragmentos das porções cranial, média e caudal do retalho cutâneo para análise histopatológica. A análise morfométrica mostrou diferença significativa para o número de novos vasos sanguíneos nas partes média e caudal do retalho cutâneo no grupo tratado. O óleo de copaíba mostra-se eficiente no aumento da neoangiogênese em retalhos cutâneos subdérmicos de ratos
Chemical composition and bioactivity of Citrus aurantifolia and Citrus reticulata peel oils and enantiomers of their major constituents against Sitophilus zeamais
Peel oils from Citrus aurantifolia and C. reticulata cultivated in the Northeast of Brazil were analyzed by GC-FID (Gas Chromatography with Flame Ionization Detection) and GC-MS (Gas Chromatography Mass Spectrometric Detection). Their insecticidal activities and both of the enantiomeric forms of the main constituent limonene [(R)-(+)-Limonene) and (S)-(-)-Limonene)] were evaluated against Sitophylus zeamais under laboratory conditions. Results were compared with deltamethrin (K-obiol 25 CE) as a positive control. Chromatographic analysis of Citrus oils showed limonene as the main constituents, with 38.9% in C. aurantifolia and 80.2% in C. reticulata. Peel oil of C. reticulata proved to be more toxic than C. reticulata oil towards S. zeamais adult by contact, ingestion and fumigant tests (LC50 = 71.18 µL mL-1 LC50 = 1.52 µL g-1, LC50 =41.92 µL L-1 air, respectively). Non-significant difference was found between (R) and (S)-Limonene in contact and fumigant tests. However, (R)-Limonene in ingestion test exhibited higher toxicity against S. zeamais than the (S)-Limonene. Deltamethrin was much more toxic in contact and ingestion bioassays than Citrus oils and two enantiomeric forms of limonene. Repellent bioassay also revealed that C. reticulata oil was more repellent than C. aurantifolia. In the repellency test, S. zeamais adult was more susceptible to (S)-Limonene than the (R)-Limonene at a lower concentration. The results of this study suggested that, in addition to behavior effect on S. zeamais, the Citrus oils affected by different ways, i.e., via the cuticle, digestive and respiratory systems, and the two enantiomeric forms of limonene showed different insecticidal properties
Insecticidal activity of Melaleuca leucadendron and Citrus reticulata essential oils against larvae of Plutella xylostella
Plutella xylostella, commonly known as the diamondback moth, is one of the most important pests of cruciferous crops in irrigated farming in the Northeast of Brazil at the municipality of Garanhuns-Pernambuco, causing direct damage to cabbage, with losses as much as 100%. The synthetic insecticides have been the main control strategy for this pest. The use of these insecticides has facilitated the emergence of generations of more resistant insects and caused the contamination of crops with toxic residues, thereby placing human health at risk. In order to establish new control practices with lower mammalian toxicity and low persistence in the environment, essential oils extracted from plants have been widely tested as an alternative to these synthetic insecticides. The aim of the present study was to evaluate the insecticidal effects of leaf and peel essential oils of Melaleuca leucadendron and Citrus reticulata on third instar of P. xylostella 24h after treatment. Results were compared with deltamethrin (Decis 25 E.C.) and azadirachtin (Azamax) as positive controls.The leaf disc immersion method was used to determine toxicity of larvae. All evaluated oils showed insecticidal activity against larvae of P. xylostella since they caused significant mortality (p < 0.05), higher than the negative control (methanol). The Citrus peel oil was 5.8 fold more active than Melaleuca leaf oil. When the oils were compared with the standard of efficiency (Decis 25 E.C. and Azamax), we found that toxicity of Citrus oil on larvae was 1.6 fold more active than the commercial insecticide Decis 25 E.C. On the other hand, Azamax was only 1.6 fold more active than Citrus oil. The Citrus oil showed a strong insecticidal activity against P. xylostella 24h after treatment, hence demonstrated potential for its development as a botanical insecticide. However further studies are needed, especially to evaluate the cost/benefit ratio regarding its use in the integrated pest management
Toxicity against Artemia salina of the zoanthid Palythoa caribaeorum (Cnidaria: Anthozoa) used in folk medicine on the coast of Pernambuco, Brazil
Palythoa caribaeorum is a zoanthid whose mucus is traditionally used by fishermen communities on the southern coast of the state of Pernambuco as an anesthetic and anti-inflammatory agent, as well as for the treatment of topical wounds. In order to evaluate a possible toxicity, hexane and ethanol extracts of the zoanthid obtained from the beaches of Piedade (PCP-H; PCP-E), Guadalupe (PCG-H; PCG-E), and Suape (PCS-H; PCS-E) were tested against Artemia salina larvae. Among the six extracts tested, PCP-H, PCP-E, PCS-H, and PCS-E showed low toxicity, with LC50 values above 250μg/mL. On the other hand, PCG-H (80 < LC50 < 250μg/mL) was categorized as moderately toxic, while PCG-E (LC50 < 80μg/mL) was considered as highly toxic, with its degree of toxicity close to that of the standard drug cyclophosphamide (LC50 = 19.7μg/mL). The results indicate the presence of toxic compounds in the zoanthid obtained from Guadalupe and they suggest caution in the use of P. caribaeorum as a folk remedy. The variations found in the extracts of the tested Pernambucan populations of P. caribaeorum corroborate previous reports that the toxic action of this zoanthid is not inherent to the species, but it is influenced by environmental conditions and associated organisms
Allelopathy, an alternative tool to improve cropping systems. A review
Known since ancient times, the phenomenon of allelopathy has recently received greater
attention from researchers and farmers worldwide. Crop failures and low yields caused by
the reseeding, overseeding, crop rotation and replanting of fruit trees in orchards are
believed to be caused by allelopathic activity. Moreover, the expensive and
environmentally impacting herbicides for weed control have motivated studies directed at
developing cheaper, environmentally-friendly alternatives. Despite the difficulties in
separating chemical interference from other mechanisms, more modern approaches have
produced consistent and conclusive data on this topic. The release and dynamics of
allelochemicals in the soil are discussed herein. Examples of allelopathic crops, the
allelochemicals produced and their uses in cropping systems are also presented along with
current research trends regarding allelopathy
Brazilian Flora 2020: Leveraging the power of a collaborative scientific network
International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora