Antiproliferative Activity of Fucan Nanogel

Sulfated fucans comprise families of polydisperse natural polysaccharides based on sulfated L-fucose. Our aim was to investigate whether fucan nanogel induces cell-specific responses. To that end, a non toxic fucan extracted from Spatoglossum schröederi was chemically modified by grafting hexadecylamine to the polymer hydrophilic backbone. The resulting modified material (SNFuc) formed nanosized particles. The degree of substitution with hydrophobic chains was close to 100%, as estimated by elemental analysis. SNFfuc in aqueous media had a mean diameter of 123 nm and zeta potential of −38.3 ± 0.74 mV, as measured by dynamic light scattering. Nanoparticles conserved their size for up to 70 days. SNFuc cytotoxicity was determined using the MTT assay after culturing different cell lines for 24 h. Tumor-cell (HepG2, 786, H-S5) proliferation was inhibited by 2.0%–43.7% at nanogel concentrations of 0.05–0.5 mg/mL and rabbit aorta endothelial cells (RAEC) non-tumor cell line proliferation displayed inhibition of 8.0%–22.0%. On the other hand, nanogel improved Chinese hamster ovary (CHO) and monocyte macrophage cell (RAW) non-tumor cell line proliferation in the same concentration range. The antiproliferative effect against tumor cells was also confirmed using the BrdU test. Flow cytometric analysis revealed that the fucan nanogel inhibited 786 cell proliferation through caspase and caspase-independent mechanisms. In addition, SNFuc blocks 786 cell passages in the S and G2-M phases of the cell cycle.     

Trypanocidal Action of (?)-Elatol Involves an Oxidative Stress Triggered by Mitochondria Dysfunction

Natural compounds have shown good potential for the discovery of new chemotherapeutics for the treatment of Chagas’ disease. Recently, our group reported the effective trypanocidal activity of (−)-elatol, extracted from the red macroalgae Laurencia dendroidea present in the Brazilian coast against Trypanosoma cruzi. However, the mechanism of action of this compound has remained unclear. There are only hypotheses concerning its action on mitochondrial function. Here, we further investigated the mechanisms of action of (−)-elatol on trypomastigotes of T. cruzi. For this, we evaluated some biochemical alterations in trypomastigotes treated with (−)-elatol. Our results show that (−)-elatol induced depolarization of the mitochondrial membrane, an increase in the formation of mitochondrial superoxide anion and loss of cell membrane and DNA integrity. Additionally, (−)-elatol induced formation of autophagic vacuoles and a decrease in cell volume. All together, these results suggest that the trypanocidal action of (−)-elatol involves multiple events and mitochondria might be the initial target organelle. Our hypothesis is that the mitochondrial dysfunction leads to an increase of ROS production through the electron transport chain, which affects cell membrane and DNA integrity leading to different types of parasite death.     

Phlorotannin Extracts from Fucales Characterized by HPLC-DAD-ESI-MSn: Approaches to Hyaluronidase Inhibitory Capacity and Antioxidant Properties

Purified phlorotannin extracts from four brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus), were characterized by HPLC-DAD-ESI-MSⁿ. Fucophloroethol, fucodiphloroethol, fucotriphloroethol, 7-phloroeckol, phlorofucofuroeckol and bieckol/dieckol were identified. The antioxidant activity and the hyaluronidase (HAase) inhibitory capacity exhibited by the extracts were also assessed. A correlation between the extracts activity and their chemical composition was established. F. spiralis, the species presenting higher molecular weight phlorotannins, generally displayed the strongest lipid peroxidation inhibitory activity (IC₅₀ = 2.32 mg/mL dry weight) and the strongest HAase inhibitory capacity (IC₅₀ = 0.73 mg/mL dry weight). As for superoxide radical scavenging, C. nodicaulis was the most efficient species (IC₅₀ = 0.93 mg/mL dry weight), followed by F. spiralis (IC₅₀ = 1.30 mg/mL dry weight). These results show that purified phlorotannin extracts have potent capabilities for preventing and slowing down the skin aging process, which is mainly associated with free radical damage and with the reduction of hyaluronic acid concentration, characteristic of the process.     

Medium Light and Medium Roast Paper-Filtered Coffee Increased Antioxidant Capacity in Healthy Volunteers: Results of a Randomized Trial

We compared the effects of medium light roast (MLR) and medium roast (MR) paper-filtered coffee on antioxidant capacity and lipid peroxidation in healthy volunteers. In a randomized crossover study, 20 volunteers consumed 482?±?61?ml/day of MLR or MR for four weeks. Plasma total antioxidant status (TAS), oxygen radical absorbance capacity (ORAC), oxidized LDL and 8-epi-prostaglandin F2α, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity were measured at baseline and after the interventions. MLR had higher chlorogenic acids-(CGA; 334?mg/150?mL) and less caffeine (231?mg/150?ml) than MR had (210 and 244?mg/150?ml, respectively). MLR also had fewer Maillard reaction products (MRP) than MR had. Compared with baseline, subjects had an increase of 21 and 26?% in TAS, 13 and 13?% in CAT, 52 and 75?% in SOD, and 62 and 49?% in GPx after MLR and MR consumption (P?相似文献   

Stability of Carotenoids, Total Phenolics and In Vitro Antioxidant Capacity in the Thermal Processing of Orange-Fleshed Sweet Potato (Ipomoea batatas Lam.) Cultivars Grown in Brazil

Intervention strategies regarding the biofortification of orange-fleshed sweet potato, which is a rich source of carotenoids for combating vitamin A deficiency, are being developed in Brazil. This study was conducted to evaluate the concentrations of individual carotenoids, total phenolic compounds and antioxidant capacity in the roots of four biofortified sweet potato cultivars that were raw or processed by four common heat treatments. HPLC, Folin-Ciocalteu, DPPH and ABTS assays were used. All cultivars showed high levels of carotenoids in raw roots, predominantly all-trans-β-carotene (79.1-128.5?mg.100?g(-1) DW), suggesting a high estimated vitamin A activity. The CNPH 1194 cultivar reported carotenoids values highest than those of other cultivars (p?相似文献   

Path analysis for selection of drought tolerant sugarcane genotypes through physiological components

Water deficit is among the main environmental factors limiting agricultural productivity of sugarcane in Northeast Brazil by affecting virtually every aspect of plant growth, with consequent reduction of the agro-industrial productivity of this crop. This study aimed to use path analysis to evaluate the physiological components of sugarcane under two water conditions, with photosynthesis as the basic variable, in order to obtain subsidies that can help the genetic breeding of this crop by selection of superior clones with drought tolerance. The experiment was carried out in a greenhouse with a completely randomized experimental design, 4 × 2 factorial arrangements (four sugarcane genotypes × two soil moisture regimes: control, with 80-100% available water and stressed, with 0-20% water available) and with four replications. Each plot consisted of one pot with 12 kg of substrate containing one plant. Treatments were maintained at a humidity close to field capacity with daily replacement of the evapotranspired water with a water supply for 66 days of cultivation for treatments under stress. Evaluations were conducted on the fourth day after severe water stress at 70 days of cultivation. Data from nine physiological variables were considered, with six of these being used in the model after exclusion of those that were contributing to multicollinearity. Variables used in path analysis were enough to explain the variation found in photosynthesis under both water conditions. Stomatal conductance, transpiration and the SPAD index should be considered as a priority in breeding programs for sugarcane aiming to get more productive and tolerant genotypes to water stress, and selection indexes should be used with due consideration of these variables to promote gains in photosynthesis.     

Comparison of lignin and cellulose solubilities in ionic liquids by COSMO-RS analysis and experimental validation

In this work, the solubilities of lignin and cellulose in ionic liquids (ILs) have been analyzed and compared by COSMO-RS simulation. The excess enthalpy of the IL + lignin/cellulose mixtures is evaluated as reference property to describe the affinity of lignin and cellulose for different ionic liquids, in terms of the intermolecular interactions contributing to their mixing properties. Thus, the anion plays the main role in the dissolution process of both lignin and cellulose, in which the hydrogen bonding forces are the major interactions. The most promising anions for the cellulose and lignin dissolution are acetate, formate and chloride, whereas different cations can be employed. Computational results indicated that a rational combination of the anions and cations allows designing ILs able to dissolve with different selectivity lignin and cellulose. Some of these solutions are tested in the laboratory to validate the model employed and the regenerated solids are analyzed by FTIR spectroscopy.     

Geographical origin and drying methodology may affect the essential oil of Lippia alba (Mill) N.E. Brown

Lippia alba (Mill.) N.E. Brown, the ginger grass, is a medicinal and aromatic plant widely used in Latin America. In this work the effect of the geographical origin and different drying methodologies on L. alba leaves production, essential oil content and composition were evaluated. Field experiments were conducted in three different municipalities (Amargosa, Cruz das Almas and Santo Antônio de Jesus) from Bahia region (Brazil) and two drying methodologies (traditional and artificial with controlled conditions) were assessed. Fresh and dried leaves essential oils were extracted by hydro-distillation and their volatiles were determined by gas chromatography.The geographical origin affected the mass production, essential oil content and both qualitative and quantitative fractions of their composition. Leaves from Cruz das Almas had higher yield in essential oil content. Overall, 26 oil constituents were identified. Carvone, germacrene D and limonene were the main oil constituents. The drying methodologies combined with the geographic origin influenced essential oil composition showing that L. alba constituents were influenced by post-harvest treatments. Some constituents were sensitive to both methods applied, while some enhanced their content like germacrene D.     

Low-Salinity Acclimation of Juvenile Marine Goliath Grouper Epinephelus itajara

The ability of marine goliath grouper to survive in waters of low salinity was investigated by collecting juvenile individuals from the wild in full-strength seawater and either transferring them directly to fresh water or acclimating them over a 96-h period to fresh water. Juvenile goliath grouper (n = 49; mean 23.4 cm SL; SD 4.1; mean 339.1 g; SD 89.3) tolerated transfers from seawater (30 ppt) to freshwater (<1 ppt), and survived thereafter for a period of 28 d in strictly fresh water, with no observed adverse effects. However, the salinity tolerance was influenced by rate of exposure, as no deaths were observed when the fish were given a gradual decrease in salinity, but 60% of the individuals died when transferred abruptly from seawater into fresh water.     

Optimization of Enzymatic Treatments for Deskinning of Catfish Nuggets

One collagenase (CLS1^®) and two proteases (Proleather FG-F^® and Protease N^®) were used to deskin the peritoneal membrane of catfish nuggets. The factors were used in a full factorial experiment design: enzyme solution concentration (0.2, 0.3, and 0.4% by weight), temperature of enzyme solution (30, 37, and 44°C), and immersion time (10, 15, and 20 min). Contour plots showed that the enzyme Proleather FG-F^® maximized whiteness of catfish nuggets at 40–44°C for 15–19 min. Treatment of the enzyme Proleather FG-F^® at 0.2% for 15 min had the highest yield (103.4%) at 44°C. Enzymatic skinning has potential in removing the peritoneal membrane from catfish nuggets, improving color (whiteness), and yield.