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The search for effective and less toxic drugs for the treatment of Cutaneous Leishmaniasis (CL) is desirable due to the emergence of resistant parasites. The present study shows the preparation, characterization and in vitro antileishmanial activity of green-based silver nanoparticles (AgNPs) with Cashew Nutshell Liquid (CNSL, main constituents: anacardic acid (AA) and cardol (CD). The synthesis of silver nanoparticles was achieved by reduction with sodium borohydride in the presence of anacardic acid or cardol under microwave irradiation (400 W, 60 °C, 5 min) resulting in AgAA and AgCD. In vitro assay showed opposite effects for AgAA and AgCD. While AgAA is highly toxic to macrophages (CC50 = 6.910 µg mL-1) and almost non-toxic for L.braziliensis (IC50 = 86.61 µg mL-1), AgCD results very selective toward killing the parasite (CC50 = 195.0 µg mL-1, IC50 = 11.54 µg mL-1). AA's higher polarity and conical shape easily promote cell lysis by increasing cell permeability, while CD has a protective effect: for that reason, AA and AgAA were not further used for tests. CD (EC50 = 2.906 µg mL-1) had higher ability to kill intracellular amastigotes than AgCD (EC50 = 16.00 µg mL-1), however, less intact cells were seen on isolated CD tests. In addition, considering that NO is one of the critical molecular species for the intracellular control of Leishmania, we used Griess colorimetric test to analyze the effect of treatment with AgCD and CD. Overall, the in vitro antileishmanial tests indicate that AgCD should be further explored as a promising non-toxic treatment for CL.

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Cutaneous leishmaniasis (CL) is a neglected tropical disease (NTD), endemic mainly in low-income countries that lack adequate basic health care. The emergence of resistant parasites to pentavalent antimonials has led to the search for new treatments for CL. Photodynamic therapy (PDT) is a promising non-invasive and less toxic alternative for the treatment of CL. The present work describes the synthesis, characterization and photodynamic effect against CL of a new metalloporphyrin Pd (II) meso-tetra[4-(2-(3-n-pentadecylphenoxy)ethoxy]phenylporphyrin (PdP) derived from the cashew nut shell liquid (CNSL). The PdP complex presented a singlet oxygen quantum yield of 0.49, favoring a type II photochemical reaction. The results of the photodynamic experiment carried out with PdP on the promastigote forms of Leishmania braziliensis indicated a mortality percentage of 70 % of the cells when compared to the control after exposure to blue light (λ = 420 nm). Besides this, the metalloporphyrin PdP did not show considerable toxicity to macrophages, indicating the cell viability of the compound. Therefore, this metalloporphyrin derived from biomass represents an interesting alternative as a potential therapeutic drug for the treatment of CL through PDT, especially for patients with intolerance to the chemotherapeutic drugs currently available.

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In this work we report the synthesis of new hybrid nanomaterials in the core/shell/shell morphology, consisting of a magnetite core (Fe3O4) and two consecutive layers of oleic acid (OA) and phthalocyanine molecules, the latter derived from cashew nut shell liquid (CNSL). The synthesis of Fe3O4 nanoparticle was performed via co-precipitation procedure, followed by the nanoparticle coating with OA by hydrothermal method. The phthalocyanines anchorage on the Fe3O4/OA core/shell nanomaterial was performed by facile and effective sonication method. The as obtained Fe3O4/OA/phthalocyanine hybrids were investigated by Fourier transform infrared spectroscopy, X-ray diffraction, UV-visible spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis and magnetic measurements. TEM showed round-shaped nanomaterials with sizes in the range of 12-15 nm. Nanomaterials presented saturation magnetization (Ms) in the 1-16 emu/g and superparamagnetic behavior. Furthermore, it was observed that the thermal stability of the samples was directly affected by the insertion of different transition metals in the ring cavity of the phthalocyanine molecule.

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In this work, the meso-tetra[4-(2-(3-n-pentadecylphenoxy)ethoxy]phenylporphyrin (H2P), obtained from the cashew nut shell liquid (CNSL), and its zinc (ZnP) and copper (CuP) metallic complexes, were applied as emitting layers in organic light emitting diodes (OLEDs). These compounds were characterized via optical and electrochemical analysis and the electroluminescent properties of the device have been studied. We performed a cyclic voltammetry analysis to determine the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) energy levels for the porphyrins, in order to select the proper materials to assemble the device. H2P and ZnP presented fluorescence emission band in the red region, from 601 nm to 718 nm. Moreover, we verified that the introduction of bulky substituents hinders the π⁻π stacking, favoring the emission in the film. In addition, the strongest emitter, ZnP, presented a threshold voltage of 4 V and the maximum irradiance of 10 µW cm-2 with a current density (J) of 15 mA cm-2 at 10 V. The CuP complex showed to be a favorable material for the design of OLEDs in the infrared. These results suggest that the porphyrins derived from a renewable source, such as CNSL, is a promising material to be used in organic optoelectronic devices such as OLEDs.

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This work describes the synthesis, characterization, and photocatalytic activity of new composite nanomaterials based on ZnO nanostructures impregnated by lipophlilic porphyrins derived from cashew nut shell liquid (CNSL). The obtained nanomaterials were characterized by X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and steady-state photoluminescence spectra (PL). The results confirm nanostructures showing average diameter of 55 nm and an improved absorption in the visible region. Further, the FTIR analysis proved the existence of non-covalent interactions between the porphyrin molecules and ZnO. The photocatalytic activity of prepared photocatalysts was investigated by degradation of rhodamine B (RhB) in aqueous solution under visible light irradiation and natural sunlight. It was demonstrated that the photocatalytic activity increases in the presence of the porphyrins and, also, depends on the irradiation source. The development of composite photocatalysts based on porphyrins derived from CNSL provides an alternative approach to eliminate efficiently toxic wastes from water under ambient conditions.

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This paper describes the investigation and development of a novel magnetic drug delivery nanosystem (labeled as MO-20) for cancer therapy. The drug employed was oncocalyxone A (onco A), which was isolated from Auxemma oncocalyx, an endemic Brazilian plant. It has a series of pharmacological properties: antioxidant, cytotoxic, analgesic, anti-inflammatory, antitumor and antiplatelet. Onco A was associated with magnetite nanoparticles in order to obtain magnetic properties. The components of MO-20 were characterized by XRD, FTIR, TGA, TEM and Magnetization curves. The MO-20 presented a size of about 30 nm and globular morphology. In addition, drug releasing experiments were performed, where it was observed the presence of the anomalous transport. The results found in this work showed the potential of onco A for future applications of the MO-20 as a new magnetic drug release nanosystem for cancer treatment.

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