Silver nanoparticles from residual biomass: Biosynthesis, characterization and antimicrobial activity.

The industrial effluent contaminated with organic pollutants has been causing an increase in the toxicity of the ecosystem, causing a great environmental impact. Thus, the present work aims the green synthesis of silver nanoparticles (AgNPs) from Aloe vera, its characterization and antimicrobial activity against Pseudomonas aeruginosa (ATCC 27853) and Staphylococcus aureus (ATCC 25923). AgNPs were characterized by X-ray diffraction (XRD), Scanning Electronic Microscopy with Energy Dispersive Spectroscopy (SEM-EDS), Zeta Potential (ZP) and N2 porosimetry (BET/BJH method). Antimicrobial activity were carried out by Minimal Inhibitory Concentration (MIC) method. The XRD demonstrated characteristic peaks of AgNPs at 38.29°; 44.55° and 64.81°, and SEM-EDS micrographs showed that AgNPs produced by biomolecules of Aloe vera extract resulted in a weight concentration around 92.59% silver, 7.15% oxygen and 0.26% chlorine. Regarding zeta potential, all samples showed negative electric charge (around -35.3 mV), while N2 porosimetry resulted in a surface specific area of 6.09 m2 g-1, with a volume and diameter pore of 0.032 cm³ g-1 and 33.47, respectively. Antimicrobial activity was observed at 15.62 µg mL-1 and 31.25 µg mL-1 for P. aeruginosa and S. aureus, respectively. Thus, AgNPs can be considered a promising nanoparticle for degradation of organic pollutants in aqueous solution as well as an adjuvant for treatment of microbial infections.

Anti-inflammatory effect of geranium nanoemulsion macrophages induced with soluble protein of Candida albicans.

Pelargonium graveolens is a member of the Geraniaceae family and has been used in folk medicine in many countries because of its anti-inflammatory activity. No studies have yet been reported to evaluate the anti-inflammatory activity of a nanoemulsion containing geranium oil (GO) model in macrophages. In this study the anti-inflammatory effect of Geranium nanoemulsion (NEG) macrophages induced with soluble proteins of Candida albicans was investigated. GO presented citronellol (17.74%) and geraniol (14.43%) as main constituents. The characterization in NEG was demonstrated, showing the particle size of 164 ± 3.5 nm, PDI of 0.12 ± 0.006 and zeta potential -10 mV ± 1.7. The MIC obtained for NEG and GO were 3.64 µg ml-1 and 1.82 µg ml-1, respectively. The viability of the macrophages treated with NEG and GO concentrations (1/2 x, 1x and 2x MIC) was evaluated. There was a significant reduction of viability and the MTT assay was not confirmed after the LDH assay. Anti-inflammatory activity was evaluated by determining nitric oxide (NO), cytokines (interleukin IL-1, IL-6 and IL-10), tumor necrosis factor-α (TNF) and the expression levels gene of interleukin (IL-2), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). The apoptosis inhibition capacity was assessed by determination of INFγ, caspase 3 and caspase 8. The results indicated that there was a significant increase of NO in the levels after treatment with NEG and significantly reduced levels after treatment with GO. The cytokines (IL-1, IL-6, IL-10, and TNF) were evaluated and NEG (½ x, 1x MIC) decreased IL-1 levels by 1.25-1.37 times, respectively. The NEG did not decrease IL-6 levels and a significant increase was observed for IL-10. GO significantly decreased IL-6 and IL-10 levels. There was a significant decrease in IL-2 and COX-2 levels and increased levels of iNOs. The levels of IFNγ and caspase-3 after treatment with NEG decreased indicating an anti-inflammatory effect and can inhibit apoptosis. Finally, the levels of caspase-8 do not change. Thus, pretreatment with NEG induced an anti-inflammatory effect against soluble proteins of C. albicans model macrophages.

Effect of the treatment with Achyrocline satureioides (free and nanocapsules essential oil) and diminazene aceturate on hematological and biochemical parameters in rats infected by Trypanosoma evansi.

This study aimed to verify the effect of the treatment with A. satureioides essential oil (free and nanoencapsulated forms) and diminazene aceturate on hematological and biochemical variables in rats infected by Trypanosoma evansi. The 56 rats were divided into seven groups with eight rats each. Groups A, C and D were composed by uninfected animals, and groups B, E, F and G were formed by infected rats with T. evansi. Rats from groups A and B were used as negative and positive control, respectively. Rats from the groups C and E were treated with A. satureioides essential oil, and groups D and F were treated with A. satureioides nanoencapsulated essential oil. Groups C, D, E and F received one dose of oil (1.5 mL kg(-1)) during five consecutive days orally. Group G was treated with diminazene aceturate (D.A.) in therapeutic dose (3.5 mg kg(-1)) in an only dose. The blood samples were collected on day 5 PI for analyses of hematological (erythrocytes and leukocytes count, hemoglobin concentration, hematocrit, mean corpuscular and mean corpuscular hemoglobin concentration) and biochemical (glucose, triglycerides, cholesterol, alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, urea and creatinine) variables. A. satureioides administered was able to maintain low parasitemia, mainly the nanoencapsulated form, on 5 days post infection. On the infected animals with T. evansi treated with A. satureioides essential oil (free and nanocapsules) the number of total leucocytes, lymphocytes and monocytes present was similar to uninfected rats, and different from infected and not-treated animals (leukocytosis). Treatment with A. satureioides in free form elevated levels of ALT and AST, demonstrating liver damage; however, treatment with nanoencapsulated form did not cause elevation of these enzymes. Finally, treatments inhibited the increase in creatinine levels caused by infection for T. evansi. In summary, the nanoencapsulated form showed better activity on the trypanosome; it did not cause liver toxicity and prevented renal damage.