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1.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208560

RESUMO

Pectis elongata is found in the northern and northeastern regions of Brazil. It is considered a lemongrass due to its citric scent. The remarkable citral content and the wide antimicrobial properties and bioactive features of this terpene make this essential oil (EO) eligible for several industrial purposes, especially in cosmetics and phytotherapics. However, to address the problems regarding citral solubility, nano-emulsification is considered a promising strategy thanks to its improved dispersability. Thus, in this paper we propose a low-energy approach for the development of citral-based nano-emulsions prepared with P. elongata EO. The plant was hydrodistillated to produce the EO, which was characterized with a gas chromatograph coupled to mass spectrometry. The nano-emulsion prepared by a non-heated water titrating (low-energy) method was composed of 5% (w/w) EO, 5% (w/w) non-ionic surfactants and 90% (w/w) deionized water and was analyzed by dynamic light scattering. Levels of citral of around 90% (neral:geranial-4:5) were detected in the EO and no major alteration in the ratio of citral was observed after the nano-emulsification. The nano-emulsion was stable until the 14th day (size around 115 nm and polydispersity index around 0.2) and no major alteration in droplet size was observed within 30 days of storage. Understanding the droplet size distribution as a function of time and correlating it to concepts of compositional ripening, as opposing forces to the conventional Ostwald ripening destabilization mechanism, may open interesting approaches for further industrial application of novel, low-energy, ecofriendly approaches to high citral essential oil-based nano-emulsions based on lemongrass plants.


Assuntos
Monoterpenos Acíclicos/isolamento & purificação , Emulsões/química , Óleos Voláteis/isolamento & purificação , Monoterpenos Acíclicos/química , Brasil , Cymbopogon/química , Cromatografia Gasosa-Espectrometria de Massas , Monoterpenos/química , Óleos Voláteis/química , Extratos Vegetais/isolamento & purificação , Tensoativos/química , Água/química
2.
Biomed Pharmacother ; 134: 111109, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341050

RESUMO

Cutaneous leishmaniasis (CL) is a neglected tropical skin disease caused by the protozoan genus Leishmania. The treatment is restricted to a handful number of drugs that exhibit toxic effects, limited efficacy, and drug resistance. Additionally, developing an effective topical treatment is still an enormous unmet medical challenge. Natural oils, e.g. the oleoresin from P. emarginatus fruits (SO), contain various bioactive molecules, especially terpenoid compounds such as diterpenes and sesquiterpenes. However, its use in topical formulations can be impaired due to the natural barrier of the skin for low water solubility compounds. Nanoemulsions (NE) are drug delivery systems able to increase penetration of lipophilic compounds throughout the skin, improving their topical effect. In this context, we propose the use of SO-containing NE (SO-NE) for CL treatment. The SO-NE was produced by a low energy method and presented suitable physicochemical characteristic: average diameter and polydispersity index lower than 180 nm and 0.2, respectively. Leishmania (Leishmania) amazonensis-infected BALB/c mice were given topical doses of SO or SO-NE. The topical use of a combination of SO-NE and intraperitoneal meglumine antimoniate reduced lesion size by 41 % and tissue regeneration was proven by histopathological analyses. In addition, a reduction in the parasitic load and decreased in the level of IFN-γ in the lesion may be associated, as well as a lower level of the cytokine IL-10 may be associated with a less intense inflammatory process. The present study suggests that SO-NE in combination meglumine antimoniate represents a promising alternative for the topical treatment of CL caused by L. (L.) amazonensis.


Assuntos
Fabaceae , Leishmania mexicana/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Extratos Vegetais/farmacologia , Pele/efeitos dos fármacos , Tripanossomicidas/farmacologia , Administração Tópica , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Composição de Medicamentos , Quimioterapia Combinada , Emulsões , Fabaceae/química , Feminino , Interações Hospedeiro-Parasita , Leishmania mexicana/crescimento & desenvolvimento , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Antimoniato de Meglumina/farmacologia , Mesocricetus , Camundongos Endogâmicos BALB C , Nanopartículas , Carga Parasitária , Extratos Vegetais/isolamento & purificação , Pele/parasitologia , Pele/patologia , Tripanossomicidas/isolamento & purificação
3.
Exp Parasitol ; 215: 107919, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32442440

RESUMO

Rhipicephalus microplus, the cattle tick, is a major cause of economic losses in bovine production. Due to the widespread acaricidal resistance to commercially available products, as well as their toxicity and environmental impact, alternative control methods are required. Nanoformulations produced from plant extracts as bioactive substances are very promising as innovative acaricidal agents. Thus, the aim of this study was to evaluate the in vitro repellent activity of Pilocarpus spicatus essential oil and its nanoemulsion against R. microplus, using larval repellent test (RT). The essential oil was extracted by hydrodistillation, using a Clevenger-type apparatus. The nanoemulsion was prepared with 5% essential oil, 5% tween 80, and 90% water, using the phase inversion method (50 mg/mL). Limonene was the major component (46.8%) of the essential oil, as determined by gas chromatography-mass spectrometry (GC/MS) and confirmed by flame ionization detection (GC/FID). According to the RT results, the essential oil had a repellent activity greater than 69%, from concentrations of 3.12 mg/mL (69.81 ± 10%) to 50 mg/mL (98.10 ± 0.6%), whereas the nanoemulsion at 50 mg/mL presented repellent activities of 97.14 ± 1.37% and 97.89 ± 0.52% 6 and 10 h after treatment, respectively. These values regarding to total repellency were very close to those calculated for mortality corrected by Abbott's formula. The phase inversion method preserved the chemical and physical characteristics of the essential oil since both reached an equal repellent effect at the same concentration. Therefore, P. spicatus essential oil and nanoemulsion had excellent repellent activities against R. microplus larvae, demonstrating its potential for future use as an alternative for tick control.


Assuntos
Óleos Voláteis/farmacologia , Pilocarpus/química , Óleos Vegetais/farmacologia , Rhipicephalus/efeitos dos fármacos , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Emulsões/farmacologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Larva/efeitos dos fármacos , Limoneno/análise , Modelos Lineares , Óleos Voláteis/isolamento & purificação , Folhas de Planta/química , Óleos Vegetais/isolamento & purificação , Distribuição Aleatória , Controle de Ácaros e Carrapatos/métodos , Infestações por Carrapato/parasitologia , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/veterinária
4.
Biotechnol Lett ; 42(5): 833-843, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32026287

RESUMO

Metal nanoparticles are a promising approach for the development of new antimicrobial systems. Silver nanoparticles (AgNP) have a significant antibacterial activity through bacterial surface adsorption and oxidative stress induction, as indicated by recent observations. This research aimed to use endophytic fungi from the genus Trichoderma spp. isolated from the Bertholletia excelsa (Brazil-nut) seeds and the soil to biosynthesize AgNPs and also test their antibacterial activity. The use of these fungi for this purpose not only valorizes the Amazon biodiversity but it also uses cleaner and cheaper processes, being part of the Green Chemistry concept. The particles were analyzed through Ultraviolet-Visible Spectroscopy and ZetaSizer and the band of absorption at 420 nm was analyzed through Localized Surface Plasmon Resonance. After characterization, the AgNP were tested for antibacterial activity against several bacterial strains, when it was observed that their antibacterial activity was superior in Gram-negative bacteria.


Assuntos
Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Trichoderma/crescimento & desenvolvimento , Antibacterianos/química , Bertholletia/microbiologia , Biodiversidade , Brasil , Bactérias Gram-Negativas/efeitos dos fármacos , Química Verde , Testes de Sensibilidade Microbiana , Prata/química , Microbiologia do Solo , Ressonância de Plasmônio de Superfície , Trichoderma/metabolismo
5.
Rev. bras. farmacogn ; 29(6): 778-784, Nov.-Dec. 2019. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1057844

RESUMO

ABSTRACT Lippia alba (Mill.) N.E.Br. ex Britton & P. Wilson, Verbenaceae, is considered a great source of a bioactive volatile oil. Due to the wide range of known chemotypes, its chemical analysis is very important. Among the several activities of this volatile oil, a potential larvicidal action against Culicidae species is highlighted. However, the low water miscibility of volatile oils limits their application in aqueous media. Oil in water nano-emulsions are in the spotlight of novelty to solve this main problem. Thus, the aim of the present study was to obtain this nanostructured system with L. alba volatile oil (citral chemotype) and evaluate its larvicidal activity against Aedes aegypti and Culex quinquefasciatus larvae. The major compounds were geranial (30.02%) and neral (25.26%). Low mean droplet size (117.0 ± 1.0 nm) and low polydispersity index (0.231 ± 0.004) were observed and no major changes were observed after seven days of storage. LC50 values against C. quinquefasciatus and A. aegypti third-instar larvae were respectively 38.22 and 31.02 ppm, while LC90 values were, respectively, 59.42 and 47.19 ppm. The present study makes use of a low energy, solvent-free and ecofriendly method with reduced costs. Thus, this paper contributes significantly to phyto-nanobiotechnology of larvicidal agents, opening perspectives for the utilization of L. alba volatile oil in integrated practices of vector control.

6.
Food Chem ; 276: 475-484, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30409622

RESUMO

Jaboticaba (Myrciaria cauliflora) is considered a "super fruit" due to its remarkable phenolic content and antioxidant capacity. Despite the great potential of its peels, to our knowledge the investigation of novel nanostructured systems with this natural raw material, still considered an industrial residue, is scarce. The present study aimed to obtain nanodispersions with its peel's extract through a low energy method. Antioxidant assays were performed, showing positive results for DPPH (IC50 = 0.89 µg/mL) and FRAP (225.53 µmol equivalent ferrous sulphate/g). The chemical characterization in terms of flavonoids (2.56%) and total monomeric anthocyanins (0.80%) contents were also performed. Overall, the nanodispersion prepared with the non-ionic surfactant polysorbate 85 and the hydroalcoholic extract standardized in ellagic acid (129 µg/mL) presented the best properties regarding particle size distribution and zeta potential. Thus, it opens perspectives for the generation of novel food-grade nanodispersions through an ecofriendly approach that is in accordance to sustainable concepts.


Assuntos
Myrtaceae/química , Extratos Vegetais/química , Antocianinas/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Ácido Elágico/química , Flavonoides/análise , Frutas/química , Frutas/metabolismo , Myrtaceae/metabolismo , Nanotecnologia , Tamanho da Partícula , Polissorbatos/química
8.
Food Chem ; 257: 196-205, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622198

RESUMO

The seeds of Bixa orellana L. is widely used in food industry as a natural colorant. A major technological challenge for its utilization on aqueous food products is the low water solubility. Therefore, the present study aimed to obtain aqueous nanodispersions using this natural raw material by using a simple organic solvent-free and low energy method. Bixin and geranylgeraniol were found on the extract. The nanodispersions were prepared by addition of water on a mixture of extract and surfactant (s). The effect of the surfactants and dilution on the nanodispersions were also evaluated. Best results were achieved using polysorbate 80/sorbitan monooleate (HLB 13) (diluted in water, 1:10). The results shows the potential of this ecofriendly approach, in contrast to common methods that make use of potentially toxic organic solvents and high input of energy, which elevate the costs for further industrialization.


Assuntos
Bixaceae/metabolismo , Carotenoides/metabolismo , Extratos Vegetais/química , Bixaceae/química , Carotenoides/análise , Carotenoides/química , Carotenoides/isolamento & purificação , Diterpenos/análise , Diterpenos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais/metabolismo , Sementes/química , Sementes/metabolismo , Solventes/química , Espectrofotometria , Tensoativos/química , Termogravimetria , Água/química
9.
Molecules ; 22(11)2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-29149027

RESUMO

Baccharis reticularia DC. is a plant species from the Asteraceae family that is endemic to Brazil. Despite the great importance of Baccharis genus, no study has been carried out regarding either the phytochemical composition of B. reticularia or the evaluation of its larvicidal potential. Considering the intrinsic immiscibility of essential oils, this study shows larvicidal nanoemulsions containing the B. reticularia phytochemically characterized essential oil and its main constituent against Aedes aegypti. The major compound found was d-limonene (25.7%). The essential oil inhibited the acetylcholinesterase, one of the main targets of insecticides. The required hydrophile-lipophile balance of both nanoemulsions was 15.0. The mean droplet sizes were around 90.0 nm, and no major alterations were observed after 24 h of preparation for both formulations. After 48 h of treatment, the estimated LC50 values were 118.94 µg mL-1 and 81.19 µg mL-1 for B. reticularia essential oil and d-limonene nanoemulsions, respectively. Morphological alterations evidenced by scanning electron micrography were observed on the larvae treated with the d-limonene nanoemulsion. This paper demonstrated a simple and ecofriendly method for obtaining B. reticularia essential oil and d-limonene aqueous nanoemulsions by a non-heating and solvent-free method, as promising alternatives for Aedes aegypti control.


Assuntos
Baccharis/química , Cicloexenos/química , Cicloexenos/farmacologia , Inseticidas/química , Inseticidas/farmacologia , Terpenos/química , Terpenos/farmacologia , Aedes/efeitos dos fármacos , Animais , Brasil , Cromatografia Gasosa-Espectrometria de Massas , Larva/efeitos dos fármacos , Limoneno , Controle de Mosquitos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-28798803

RESUMO

Andiroba (Carapa guianensis) seeds are the source of an oil with a wide range of biological activities and ethnopharmacological uses. However, few studies have devoted attention to innovative formulations, including nanoemulsions. The present study aimed to obtain a colloidal system with the andiroba oil using a low-energy and organic-solvent-free method. Moreover, the preliminary residual larvicidal activity of the nanoemulsion against Aedes aegypti was evaluated. Oleic and palmitic acids were the major fatty acids, in addition to the phytosterol ß-sitosterol and limonoids (tetranortriterpenoids). The required hydrophile-lipophile was around 11.0 and the optimal nanoemulsion was obtained using polysorbate 85. The particle size distribution suggested the presence of small droplets (mean diameter around 150 nm) and low polydispersity index (around 0.150). The effect of temperature on particle size distribution revealed that no major droplet size increase occurred. The preliminary residual larvicidal assay suggested that the mortality increased as a function of time. The present study allowed achievement of a potential bioactive oil in water nanoemulsion that may be a promising controlled release system. Moreover, the ecofriendly approach involved in the preparation associated with the great bioactive potential of C. guianensis makes this nanoemulsion very promising for valorization of this Amazon raw material.

11.
Rev. bras. farmacogn ; 27(3): 401-406, May-June 2017. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1042250

RESUMO

Abstract Pterodon emarginatus Vogel, Fabaceae, is a great source of bioactive compounds. The most known and studied herbal derivative from this species is an ambar-colored oleoresin that contains vouacapane diterpenes and volatile terpenoids, such as β-caryophyllene. Some recent papers aimed to generate nanoemulsions using this oleoresin for biological applications. However, they used high-energy methods that elevate costs of the process or heating procedures, which offer the disadvantage of possible volatile substances loss. Thus, as part of our ongoing studies with nanobiotechnology of natural products, especially regarding preparation of nanoemulsions with promising plant-based oils by low cost and low energy methods, we decided to evaluate the ability of non-heating and solvent-free method to generate P. emarginatus oleoresin-based nanoemulsions. Two non-ionic surfactants were used to generate the nanoemulsions by a simple homogenization method with vortex stirrer. Low mean droplet size (<180 nm) and low polydispersity index (<0.200) were observed even after one day of preparation. The low coefficient of variation for the analyzed parameters of different batches and similar profile for droplet size distribution suggested reproducibility of the method. After 30 days, some degree of droplet growth was observed on nanoemulsion prepared with polyethyleneglycol 400 monooleate, while almost no alteration was observed for nanoemulsion prepared with polysorbate 85. Programmed temperature ramp analysis revealed that no major effects on droplet size and polydispersity index were observed, suggesting the robustness of formed nanoemulsions. Thus, the present study shows for the first time the formation of sucupira-based nanoemulsions by a simple, low cost and ecofriendly method. This study opens new perspectives for bioactive evaluation of this novel nano-product.

12.
J Nanobiotechnology ; 15(1): 2, 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-28049483

RESUMO

BACKGROUND: Preparation of nanoformulations using natural products as bioactive substances is considered very promising for innovative larvicidal agents. On this context, oil in water nanoemulsions develop a main role, since they satisfactorily disperse poor-water soluble substances, such as herbal oils, in aqueous media. Pterodon emarginatus, popularly known as sucupira, has a promising bioactive oleoresin. However, to our knowledge, no previous studies were carried out to evaluate its potential against Culex quinquefasciatus, the main vector of the tropical neglected disease called lymphatic filariasis or elephantiasis. Thus, we aimed to investigate influence of different pairs of surfactants in nanoemulsion formation and investigate if a sucupira oleoresin-based nanoemulsion has promising larvicidal activity against this C. quinquefasciatus. We also evaluated morphological alteration, possible mechanism of insecticidal action and ecotoxicity of the nanoemulsion against a non-target organism. RESULTS: Among the different pairs of surfactants that were tested, nanoemulsions obtained with polysorbate 80/sorbitan monooleate and polysorbate 80/sorbitan trioleate presented smallest mean droplet size just afterwards preparation, respectively 151.0 ± 2.252 and 160.7 ± 1.493 nm. They presented high negative zeta potential values, low polydispersity index (<0.300) and did not present great alteration in mean droplet size and polydispersity index after 1 day of preparation. Overall, nanoemulsion prepared with polysorbate 80/sorbitan monooleate was considered more stable and was chosen for biological assays. It presented low LC50 value against larvae (34.75; 7.31-51.86 mg/L) after 48 h of treatment and some morphological alteration was observed. The nanoemulsion did not inhibit acetylcholinesterase of C. quinquefasciatus larvae. It was not toxic to green algae Chlorella vulgaris at low concentration (25 mg/L). CONCLUSIONS: Our results suggest that optimal nanoemulsions may be prepared with different surfactants using a low cost and low energy simple method. Moreover, this prototype proved to be effective against C. quinquefasciatus, being considered an ecofriendly novel nanoproduct that can be useful in integrated control programs of vector control.


Assuntos
Culicidae/efeitos dos fármacos , Emulsões/toxicidade , Fabaceae/química , Controle de Insetos , Inseticidas/toxicidade , Extratos Vegetais/toxicidade , Animais , Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/fisiologia , Culicidae/fisiologia , Emulsões/química , Feminino , Inseticidas/química , Larva/efeitos dos fármacos , Larva/fisiologia , Extratos Vegetais/química
13.
Curr Top Med Chem ; 16(18): 2051-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26876517

RESUMO

Polyphenols are a large group of structurally diverse natural products, including flavonoids. One of the most bioactive compounds of this class is the flavonol quercetin, a recognized antioxidant. Despite several studies were carried out aiming to develop nanoformulations with secondary metabolites, to our knowledge, quercetin was not used as raw material for nanodispersion production without coating polymers. This type of nanosize formulation is often prepared using organic solvents and quercetin nanodispersions were prepared by emulsification evaporation technique, using 1(6).2(2) experimental factorial design, ("surfactant type" evaluated at 6 levels, "surfactant amount" and "stirring speed" evaluated at 2 levels). Variance analysis, after one day of nanodispersions preparation, revealed that only the surfactant type was statistically significant on particle size, while none of factors presented statistically significant effect on polydispersity index. Variance analysis after seven days of nanodispersions preparation revealed that either surfactant type and surfactant amount presented significant effect on particle size, while only surfactant type influenced polydispersity index. Some nanodispersions presented small diameter and narrow size distribution, suggesting potential stability of these systems. Special attention was given to nanodispersion prepared with 3 % (w/w) of polyethylene glycol 400 monooleate (expressed as function of surfactant concentration at aqueous phase). It presented mean droplet size of 129.4 ± 0.5 nm and polydispersity index of 0.173 ± 0.018, after 7 days of preparation. Low polydispersity index indicates a high homogeneity concerning particle size distribution and suggests stability of the system. Moreover, absence of coating polymers and utilization of a low energy method would be an advantage in terms of reducing costs for industrial application, without any nanosize impairment.


Assuntos
Emulsões/química , Quercetina/química , Tensoativos/química , Análise de Variância , Composição de Medicamentos/métodos , Nanoestruturas/química , Tamanho da Partícula
14.
Curr Top Med Chem ; 16(18): 2057-65, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26876518

RESUMO

Cassia grandis and Bixa orellana are important plant species with folk use and great potential for phytopharmaceuticals. Nanodispersions are disperse systems of insoluble or immiscible substances in a liquid medium that may be prepared with or without coating polymers. To our knowledge, no studies were carried in order to achieve coating-polymer free nanoformulations using B. orellana extract or any C. grandis-based nanoformulations. Thus, on the present study we aimed to develop C. grandis nanoformulations using three different coating polymers (Eudragit® L 100 55, PEG 4000 and Kollicoat®), while B. orellana nanodispersions were obtained using different surfactants (polysorbate 80, polysorbate 20, polyethylene glycol 400 monooleate, polyethylene glycol 600 monooleate, polyethylene glycol 400 dioleate and polyethylene glycol 600 dioleate) as coating polymer-free nanoformulations. Characterization of nanoformulations was performed by different parameters, including particle size, polydispersity index and zeta-potential. Our results suggested that some optimal nanoformulations were obtained for both plant species. Moreover, possible stable behavior was observed during storage period for C. grandis (30 days) and B. orellana (21 days). On this context, the present study contributes to nanobiotechnology development of phytopharmaceuticals, allowing achievement of novel nano-delivery systems with two important folk medicinal plant extracts and making them potential products for innovative phytopharmaceuticals.


Assuntos
Bixaceae/química , Cassia/química , Composição de Medicamentos/métodos , Nanopartículas/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Extratos Vegetais/química , Plantas Medicinais/química , Tensoativos/química , Temperatura
15.
PLoS One ; 11(1): e0145835, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26742099

RESUMO

Pterodon emarginatus Vogel is a Brazilian species that belongs to the family Fabaceae, popularly known as sucupira. Its oil has several biological activities, including potent larvicidal property against Aedes aegypti. This insect is the vector of dengue, a tropical disease that has been considered a critical health problem in developing countries, such as Brazil. Most of dengue control methods involve larvicidal agents suspended or diluted in water and making active lipophilic natural products available is therefore considered a technological challenge. In this context, nanoemulsions appear as viable alternatives to solve this major problem. The present study describes the development of a novel nanoemulsion with larvicidal activity against A. aegypti along with the required Hydrophile Lipophile Balance determination of this oil. It was suggested that the mechanism of action might involve reversible inhibition of acetylcholinesterase and our results also suggest that the P. emarginatus nanoemulsion is not toxic for mammals. Thus, it contributes significantly to alternative integrative practices of dengue control, as well as to develop sucupira based nanoproducts for application in aqueous media.


Assuntos
Aedes/efeitos dos fármacos , Fabaceae/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Nanoestruturas/química , Óleos Voláteis/farmacologia , Acetilcolinesterase/metabolismo , Aedes/enzimologia , Aedes/crescimento & desenvolvimento , Animais , Comportamento Animal/efeitos dos fármacos , Dengue/prevenção & controle , Emulsões , Feminino , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/metabolismo , Inseticidas/isolamento & purificação , Larva/enzimologia , Larva/crescimento & desenvolvimento , Dose Letal Mediana , Camundongos , Controle de Mosquitos/métodos , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química
16.
Rev. bras. farmacogn ; 24(6): 699-705, Nov-Dec/2014. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-741837

RESUMO

Copaiba (Copaifera duckei Dwyer, Fabaceae) oleoresin is an important Amazonian raw material. Despite its insecticidal potential, poor water solubility remains a challenge for the development of effective and viable products. Nanotechnology has emerged as a promising area to solve this problem, especially oil-in-water nanoemulsions. On this context, the aim of the present study was to develop oil-in-water nanoemulsions using copaiba oleoresin dispersed through a high internal phase; and evaluate its potential insecticidal action against Aedes aegypti larvae. Overall, 31 formulations were prepared, ranging from 11.5 ± 0.2 to 257.3 ± 4.1 nm after one day of manipulation. Some of them reached small mean droplet sizes (< 200 nm) and allowed achievement of a nanoemulsion region. The formulation consisted of 5% (w/w) of copaiba oil, 5% (w/w) of surfactant and 90% (w/w) of water, which presented mean droplet size of 145.2 ±0.9 nm and polidispersity of 0.378 ± 0.009 after one day of manipulation, and these were evaluated for larvicidal potential. According to mortality level (250 ppm - 93.3 after 48 h), this nanoemulsion was classified as a promising insecticidal agent against Aedes aegypti larvae. The present study allowed the development of low-cost ecofriendly green natural-based nanoformulations with potential larvicidal activity, using a nanobiotechnology approach.

17.
Rev. bras. farmacogn ; 24(4): 413-418, Jul-Aug/2014. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-725631

RESUMO

Essential oils are known for their insect control potential, which is mainly attributed to the presence of terpenes that interfere with hormonal and physiological processes of arthropods. The aim of the present study was to evaluate the effects of essential oil from the leaves of Eugenia sulcata Spring ex Mart., Myrtaceae, on the development of two species of agricultural pest insects, Dysdercus peruvianus and Oncopeltus fasciatus. Results showed that the essential oil induced mortality, and reduced numbers of adults. Topical treatment of Oncopeltus fasciatus using pure essential oil caused significant mortality rates (96.67%), while Dysdercus peruvianus had a higher tolerance, with 80% mortality at the end of the experiments. Results suggest that essential oil from the leaves of Eugenia sulcata may be used in agriculture for insect pest control.

18.
Rev. bras. farmacogn ; 24(3): 316-321, May-Jun/2014. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-719457

RESUMO

Myrciaria floribunda (H. West ex Willd.) O. Berg, Myrtaceae, is popularly known as "camboim-amarelo" and was collected at Restinga de Jurubatiba (RJ, Brazil). Leaves from this species were submitted to hydrodistillation to extract its essential oil. Monoterpenes were the main compounds found (53.9%), and 1,8-cineole was the major constituent (38.4%). Studies were carried out to evaluate the effects of this essential oil on the development of two species of agricultural pests (Oncopeltus fasciatus and Dysdercus peruvianus). The essential oil was considered effective against D. peruvianus and O. fasciatus, causing mortality in both insects. The LD50 values (µg/insect) observed were 112.44 µg/insect (O. fasciatus) and 309.64 µg/insect (D. peruvianus) after one day of treatment, and 72.18 µg/insect (O. fasciatus) and 94.42 µg/insect (D. peruvianus) after 22 days of treatment. The present study reports for the first time the bioinsecticidal activity of essential oil of Myrciaria floribunda leaves, and provides important data regarding the use of essential oils in complementary programs for pest control.

19.
Biomed Res Int ; 2013: 280810, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23509702

RESUMO

Manilkara subsericea (Mart.) Dubard (Sapotaceae) is popularly known in Brazil as "guracica." Studies with Manilkara spp indicated the presence of triterpenes, saponins, and flavonoids. Several activities have been attributed to Manilkara spp such as antimicrobial, antiparasitic and antitumoral, which indicates the great biological potential of this genus. In all, 87.19% of the hexanic extract from fruits relative composition were evaluated, in which 72.81% were beta- and alpha-amyrin esters, suggesting that they may be chemical markers for M. subsericea. Hexadecanoic acid, hexadecanoic acid ethyl ester, (E)-9-octadecenoic acid ethyl ester, and octadecanoic acid ethyl ester were also identified. Ethanolic crude extracts from leaves, stems, and hexanic extract from fruits exhibited antimicrobial activity against Staphylococcus aureus ATCC25923. These extracts had high IC50 values against Vero cells, demonstrating weak cytotoxicity. This is the first time, to our knowledge, that beta- and alpha-amyrin caproates and caprylates are described for Manilkara subsericea.


Assuntos
Ésteres/química , Manilkara/química , Triterpenos/química , Animais , Antibacterianos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Frutas/química , Concentração Inibidora 50 , Ácido Palmítico/análise , Extratos Vegetais/farmacologia , Staphylococcus aureus/metabolismo , Ácidos Esteáricos/análise , Células Vero
20.
Biomed Res Int ; 2013: 723181, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23484148

RESUMO

Neomitranthes obscura (DC.) N. Silveira is an endemic plant of Brazilian Atlantic Forest and widely spread in the sandbanks of "Restinga de Jurubatiba" National Park. It is popularly known by local population as "camboim-de-cachorro" or "cambuí-preto" and recognized by its black ripe fruits. However, specimens with yellow ripe fruits were localized in the "Restinga de Jurubatiba" National Park. The aim of the present study was to evaluate chemical composition of essential oils obtained from leaves and fruits of N. obscura specimens with different fruit color (black and yellow) by GC and GC-MS. Essential oils from leaves of specimens with black and yellow fruits indicated a predominance of sesquiterpenes (81.1% and 84.8%, resp.). Meanwhile, essential oil from black fruits presented a predominance of monoterpenes (50.5%), while essential oil from yellow fruits had sesquiterpenes (39.9%) as major substances. Despite previous studies about this species, including essential oil extraction, to our knowledge this is the first report on N. obscura fruits with different colors. Our results suggest the occurrence of unless two different varieties for this species.


Assuntos
Frutas/química , Magnoliopsida/química , Óleos Voláteis/química , Pigmentos Biológicos/química , Folhas de Planta/química , Árvores , Brasil
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