Ouratea fieldingiana is a native medicinal plant from Northeastern Brazil and many biological properties are due to the phenolic constituents. The objective of this work was performing the characterization of O. fieldingiana leaf constituents to correlate with antioxidant and anticholinesterase activities by in vitro and in silico studies and thus contribute to find new agents against Alzheimer’s disease. The high-performance liquid chromatography revealed the presence of the flavonoids rutin, isoquercitrin, kaempferol-3-O-rutinoside, quercetin, apigenin and amentoflavone. The antioxidant activities by the (2,2-diphenyl-1-picrylhydrazyl) (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) methodologies, showed good results with half maximal inhibitory concentration (IC50) values ranging from 5.63 to 11.47 µg mL-1 and 2.72 to 23.71 µg mL-1, respectively. Acetylcholinesterase inhibition assay pointed out the flavone apigenin with best activity. Computational studies evaluated the interaction of flavonoids with the enzyme acetylcholinesterase co-crystallized with the galantamine, used as standard. All flavonoids exhibited binding energy greater than that of galantamine, but only apigenin showed strong interaction with the active site of the enzyme and other bind probably to different allosteric centers. Then, O. fieldingiana extract and flavonoids with good anti-radical activity and presenting a broad-spectrum action against acetylcholinesterase (AChE) enzyme ought to be tested in clinical studies to discover new neuro-therapeutic candidates.

The genus Cryptostegia comprises two species, C. madagascariensis (Bojer) and C. grandiflora (Roxb. Ex R. Br) that belong to the Apocynaceae family and are widely distributed in the tropics, as in Australia, New Zealand, India and Brazil, where they cause great socioeconomic and environmental damage, as they are invaders causing damage, mainly in the cultivation of carnaúba, a native plant of great importance in the wax and derivatives industry in Northeast Brazil. Both are perennial shrubs, native to the island of Madagascar, have abundant latex and are known as rubber vine. The plants have the potential for pharmacological, biological and industrial applications. This is due to a rich source of chemical compounds (proteins, phenols, flavonoids, steroids, triterpenoids, cardiac glycosides, etc.) resulting from primary and secondary metabolism. The plants of the Cryptostegia genus showed many activities against bacteria, fungi, insects, Ae. aegypti larvae, Shistosoma sp., as well as for human health as analgesic, anti-inflammatory, antioxidant and antitumoral, and for industrial purposes acting as fibrinogenolytic, hydrolytic, anticorrosive, coagulant and depilatory for leather. Nevertheless, the toxicity is a limitation for the plant use then in order to stand out the economic potential a detailed research on toxicity and management of growing conditions is necessary.

Carvacrol (CV) and carvacryl acetate (CVA) are bioactive compounds that have anthelmintic action and the nanoencapsulation may be an alternative to potentialize their efficacy. The aim of this work was to nanoencapsulate CV and CVA using chitosan/gums and evaluate cytotoxicity and the anthelmintic activity. A 24 factorial experimental design was performed to determine the influence of gum type (arabic or chichá), amount of surfactant and the number of layers in the nanoencapsulation degree. CVA and CV presented encapsulation efficiency (EE) optimum values of 90 and 20% (experiments 8 and 9), respectively. The monolayer and bilayer formulations presented maximum size of 479 and 811 nm, respectively. Nanoencapsulated CVA (nCVA) with bilayer coating and higher surfactant levels showed good thermal stability and no toxicity. In vitro kinetics for nCVA with chitosan/chichá gum showed slower release profiles than nCVA with chitosan/gum arabic, with 50% release after 30 and 20 h, respectively. CVA and nCVA at a concentration of 150 µg mL−1 reduced the motility of H. contortus adult nematodes by 100 and 91.7%, respectively. In summary, nCVA chitosan/chichá gum showed high encapsulation efficiency, favorable release rate and anthelmintic activity against H. contortus.

AbstractIn this study, the spray drying technique was used to prepare L-ascorbic acid (AA) microparticles encapsulated with galactomannan-an extract from the seeds of the Delonix regia species. The physico-chemical characteristics, antioxidant activity, and encapsulation efficiency of the AA microparticles were evaluated and characterized using thermogravimetric analysis, differential scanning calorimetry, infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. The free-radical scavenging activity of the AA microparticles was determined at different environmental conditions using DPPH (1,1-diphenyl-2-picryl-hydrazyl). X-ray diffraction measurements demonstrated a loss of crystallinity in AA after the encapsulation process, and a DSC scan also showed the loss of the compound's melting peak. Thermogravimetric analysis showed small differences in the thermal stability of galactomannan before and after the incorporation of AA. The mean diameters of the obtained spherical microspheres were in the range of 1.39 ± 0.77 µm. The encapsulation efficiency of AA microparticles in different environmental conditions varied from 95.40 to 97.92, and the antioxidant activity showed values ranging from 0.487 to 0.550 mg mL-1.

Esferas de alginato (ALG) reticuladas com cálcio e revestidas com goma do cajueiro (GC) foram preparadas e dopadas com óleo essencial de Croton zehntneri Pax et Hoffm (Cz), visando a seu emprego como larvicida para combate ao vetor da dengue. As esferas foram caracterizadas estruturalmente por espectroscopia de infravermelho, análise térmica, microscopia eletrônica de varredura e em relação aos seus parâmetros de transporte líquido, dopagem, embebição (Q) e cinética de liberação in vitro e in vivo. Os resultados revelaram que as esferas possuem morfologia com uma alta regularidade esférica, com superfície porosa. A matriz ALG:Cz =1:1 apresentou maior dopagem e eficiência de encapsulamento e valores de Q entre 10 e 12. O perfil de liberação do óleo encapsulado apresentou-se mais prolongado nas esferas contendo goma do cajueiro, ALG-GC:Cz =1:1. A taxa de mortalidade de larvas de Stegomyia aegypti para teores de 1,81 a 4,25 mg de óleo nas esferas resultou em valores na faixa de 72 a 100%, após 24 h. A matriz polimérica mostrou-se efetiva para proteção do principio ativo até cerca de 70 dias, com perdas da ordem de 35%. A análise térmica revelou que a incorporação de Cz e GC resulta em uma matriz polimérica termicamente mais estável.

Alginate beads (ALG) crosslinked with calcium and coated with cashew gum (GC) were prepared and loaded with an essential oil from Croton zehntneri Pax et Hoffm (Cz). The beads were characterized by FTIR, thermal properties, with respect to their size, shape, larvicide loading, swelling, and in vitro and in vivo release kinetics. Results showed that beads with ALG:Cz =1:1 relative ratio showed higher loading and encapsulation efficiency, although presenting a faster release kinetics. On the other hand, ALG beads coated with GC showed Q values from 10 to 12, representing a significant increase in the hydrophilic character of the matrix. Infrared spectroscopy and thermal analysis confirmed the presence of essential oil encapsulated in beads. Morphologic investigation by SEM revealed a highly spherical and porous surface. The in vitro profile showed that the Cz oil encapsulated had a prolonged release in ALG-GC beads, probably due to the crosslinking. In vivo tests showed that the mortality degree was related to the mass of the beads, where beads having oil content from 1.81 to 4.25 mg caused larvae mortalities from 72 to 100% after 24 h. The control release system was found to be effective up to 70 days. These results showed that ALG-GC beads loaded with Cz are promising candidate for the control of Stegomyia aegypti larvae.

Antioxidantes são compostos que atuam inibindo e/ou diminuindo os efeitos desencadeados pelos radicais livres e compostos oxidantes. Os chás são bebidas populares e fontes significativas de compostos fenólicos, sendo considerados importantes integrantes das dietas devido às suas propriedades antioxidantes. O presente trabalho teve como objetivo avaliar a ação antioxidante de uma variedade de chás e condimentos mais consumidos no Brasil. Os chás analisados foram das plantas: Pneumus boldus Mold., Matricaria recutita L., Cymbopogon citratus (DC) Stapf, Baccharis trimera (Less.) DC, Camelia sinensis (L) O. Kuntze (fermentado), Camelia sinensis (não-fermentado), Lippia alba N.E. Brown,Mentha arvensis L., e Pyrus malus L. Os condimentos analisados foram: Eugenia aromatica Baill, Cinnamonum zeylanicum Blume, Laurus nobilis L. e Origanum vulgare L. O método utilizado para avaliar a ação antioxidante foi o da atividade seqüestradora de radicais livres DPPH em solução metanólica. Todas as amostras analisadas demonstraram atividade em suas diferentes concentrações. Camelia sinensis (não-fermentada) foi a mais ativa com CI50= 0,14 mg/mL, cujos principais compostos antioxidantes são epigalocatequinas. Os condimentos mais ativos foram Cinnamonum zeylanicum (CI50 = 0,37 mg/mL), Eugenia aromatica Baill (CI50 = 0,46 mg/mL) e Laurus nobilis (CI50 = 0,76 mg/mL), cujo principal antioxidante relatado foi o eugenol.

Antioxidants are compounds that remove free-radicals or minimize their availability to generate oxidative stress. Teas are popular beverages providing a significant source of phenolic compounds, important components of the human diet due to their antioxidant properties. The present work had the objective of evaluate the antioxidant action of teas and seasonings more consumed in Brazil. The analysed teas were from the plants: Pneumus boldus Mold., Matricaria recutita L., Cymbopogon citratus (DC) Stapf, Baccharis trimera (Less.) DC, Camelia sinensis (L) O. Kuntze (fermented), Camelia sinensis (not-fermented), Lippia alba N.E. Brown, Mentha arvensis L. and Pyrus malus L. The studied seasonings were: Eugenia aromatica Baill, Cinnamonum zeylanicum Blume, Laurus nobilis L. and Origanum vulgare L. The antioxidant activity was measured by the DPPH free radical scavenging method. All analysed samples demonstrated antioxidant activities. Camelia sinensis (not-fermented) (IC50= 0.14 mg/mL), was the most active and active principles are epicalocatechins. The stronger antioxidant seasonings were Cinnamonum zeylanicum (IC50 = 0.37 mg/mL), Eugenia aromatica Baill (IC50= 0.46 mg/ mL and Laurus nobilis (IC50 = 0.76 mg/mL), which presented as main antioxidant component eugenol.