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Eucalypt kraft lignin isolated in a LignoBoost™ pilot plant was characterized by GC-MS, ICP-OES, DSC, HPSEC, 31 P NMR, and HSQC 2D-NMR to be used without any further processing to produce lignin nanoparticles (LNPs) by nanoprecipitation. Tetrahydrofuran (THF) was used as a solvent, and water as a non-solvent. Microscopic analysis (TEM) showed that LNPs were regularly spherical with some hollow particles dispersed in-between, and sizes were tunable by changing the solvent dripping rate onto the non-solvent. LNP particle sizes had a bimodal distribution, with the largest population having an average apparent hydrodynamic diameter ranging from 105.6 to 75.6 nm. Colloidal dispersions of LNPs in water presented good stability in different dilutions without significant size changes upon storage at pH close to neutral for as long as 45 days. Zeta potentials around -40 mV were obtained for LNP suspensions at pH ranging from 7 to 9. The high carbohydrate content (circa 10 % on a dry basis, mostly xylans) of the lignin precursor did not interfere in LNP formation, whose antioxidant activity was expressive as demonstrated by the ABTS assay at pH 7.4, with an EC 50 of 4.04 μg mL -1 . Also, the Trolox® equivalent antioxidant capacity (TEAC) of LNPs reached 1.90 after 40 min reaction time., Competing Interests: Declaration of competing interest Luiz Pereira Ramos reports financial support was provided by National Council for Scientific and Technological Development. Giuliana Pavaneli reports financial support was provided by Coordination of Higher Education Personnel Improvement. Nothing to declare., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The interaction between galactomannans, guar gum (GG) with sodium lauryl ether sulphate (SLES) was demonstrated using conductometric, tensiometric, pyrene probe and 1 H NMR analyses. SLES and GG formed aggregates and reduced the surface tension at a critical aggregation concentration. The interaction was attributed to the presence of surfactant ethoxyl (EO) groups, since in conductometric, tensiometry and pyrene probe analyses using the non-ethoxylated form, sodium lauryl sulphate - SLS, no aggregation was observed. The aggregates formed between SLES and GG presented a negative zeta potential indicating that the polymer is surrounded by SLES and according to the dynamic light scattering analysis (DLS), presented a size of approximately 26 nm. The determination of the thermodynamic parameters showed that the aggregation occurs spontaneously and is a driven-enthalpy and entropy process. SLES and GG interaction could be explored to produce formulations with lower concentrations of surfactants, using commonly used thickeners as GG., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This study investigates conformational aspects of ulvans (F2) and their polycarboxyl derivatives obtained through periodate-chlorite oxidation (C3) followed by DEAE-Sephacel fractioning (C3b and C3c). Size exclusion chromatography coupled with laser light scattering and viscometric detection, in addition to circular dichroism (CD) and molecular modeling analyses, suggested that F2 had a compact sphere conformation with a helical motif as secondary structure. In contrast, all the polycarboxyl ulvans showed a random coil conformation, although C3c (NaSO 3 - 21.0%; COO - 1.81 mmol·g -1 ; M w 18 kg·mol -1 ) had a more rigid and constrained backbone than C3 (NaSO 3 - 21.0%; COO - 1.81 mmol·g -1 ; M w 49 kg·mol -1 ), largely due to its higher sulfate and carboxyl content. Despite the higher ionic character of C3c, its anticoagulant activity (ACA), determined by activated partial thromboplastin time (APTT) assay, was not improved compared to that of C3. Moreover, C3b (NaSO 3 - 14.1%; COO - 1.23 mmol·g -1 ; M w 8.1 kg·mol -1 ) had higher activity than F2 (NaSO 3 - 20.6.%; COO - 0.36 mmol·g -1 ; M w 123 kg·mol -1 ), even with its lower sulfate content and molar mass. These results suggest that the ACA of polycarboxyl ulvans relies on carboxyl and sulfate content and may depend, in addition, on a proper flexible conformation., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This work describes the development of polysaccharide-coated liposomes to modulate the delivery of epidermal growth factor (EGF), with the aim to produce different EGF release profiles depending on the milieu of infected wounds. For this purpose, cationic liposomes were coated with one layer of sodium alginate (ALG) followed by one layer of chitosan (CHI) using the layer-by-layer (LbL) technique. The coated liposomes exhibited apparent hydrodynamic diameters of 278 ± 36 and 216 ± 96 nm for Lip-ALG and Lip-ALG-CHI, respectively. Thus, it appears that adding the CHI layer compacted the Lip-ALG one. The incorporation efficiency of EGF was a maximum of 55% for liposomes with a polymeric coating. In vitro release experiments showed that Lip-ALG-CHI exhibits a higher release rate constant under acidic pH conditions, resembling those of infected tissue. Using an ex vivo model of EGF release in porcine ear skin, these liposomes were found to accumulate in the epidermis. Thus, coated liposomes could represent a local EGF delivery mechanism to promote healing., (Copyright © 2020 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

The mechanical pretreatments intensities on characteristics of cellulose nanocrystals (CNC) prior to acid hydrolysis was evaluated. The cellulose was submitted to mechanical pretreatment as: magnetic stirring (CNC st ), blending (CNC bl ) or grinding by 20 (CNC 20x ) and 40 (CNC 40x ) passages in a super mass colloid mill. Then, all samples were submitted to H 2 SO 4 hydrolysis and the CNC were evaluated by total mass yield (TMY%), rheological behavior, size distribution for width/length (WD), crystallinity index (CI%), OSO 3 - substitution degree (SD) and zeta potential (ζ). After hydrolysis samples exhibited the same SD (190 ± 5 mMol·kg -1 ), ζ (-55 ± 3 mV) and CI% (65 ± 2), differing only in TMY% and WD. The CNC st showed TMY% of 85%, WD of 8 ± 5 nm and 100-800 nm, with presence of cellulose nanofibers (CNF), suggesting incomplete hydrolysis. The CNC bl and CNC 20x revealed TMY% of 65 ± 1, but differed in WD of 8 ± 5 nm and 300 ± 200 nm and 8 ± 5 nm and 200 ± 170 nm, respectively. The results showed that the grinding mechanical pretreatment is mandatory for CNF isolation, but not for CNC. Stability profile after the hydrolytic procedure, CI%, morphology and similar character generated CNC with adequate features and good yield, by simple mechanical stirring or blending, reducing the production's cost and allowing industrial-scale production., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The biotechnological evolution towards the development of antigens to detect leprosy has been progressing. However, the identification of leprosy in paucibacillary patients, based solely on the antigen-antibody interaction still remains a challenge. The complexity of clinical manifestations requires innovative approaches to improve the sensitivity of assays to detect leprosy before the onset of symptoms, thus avoiding disabilities and contributing, indirectly, to reduce transmission. In this study, the strategies employed for early leprosy diagnosis were: i. using a phage-displayed mimotope (APDDPAWQNIFNLRR) which mimics an immunodominant sequence (PPNDPAWQRNDPILQ) of an antigen of Mycobacterium leprae known as Ag85B; ii. engineering the mimotope by adding a C-terminal flexible spacer (SGSG-C); iii. conjugating the mimotope to a carrier protein to provide better exposure to antibodies; iv. amplifying the signal using biotin-streptavidin detection system in an ELISA; and v. coating the optimized mimotope on a quartz crystal microbalance (QCM) sensor for label-free biosensing. The ELISA sensitivity increased up to 91.7% irrespective of the immunological profile of the 132 patients assayed. By using comparative modeling, the M. tuberculosis Ag85B was employed as a template to ascertain which features make the mimotope a good antigen in terms of its specificity. For the first time, a sensitive QCM-based immunosensor to detect anti M. leprae antibodies in human serum was used. M. leprae antibodies could also be detected in the sera of paucibacillary patients; thus, the use of a mimotope-derived synthetic peptide as bait for antibodies in a novel analytical label-free immunoassay for leprosy diagnosis exhibits great potential., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Bacterial cellulose (BC) derived materials represents major advances to the current regenerative and diagnostic medicine. BC is a highly pure, biocompatible and versatile material that can be utilized in several applications - individually or in the combination with different components (e.g. biopolymers and nanoparticles) - to provide structural organization and flexible matrixes to distinct finalities. The wide application and importance of BC is described by its common utilization as skin repair treatments in cases of burns, wounds and ulcers. BC membranes accelerate the process of epithelialization and avoid infections. Furthermore, BC biocomposites exhibit the potential to regulate cell adhesion, an important characteristic to scaffolds and grafts; ultra-thin films of BC might be also utilized in the development of diagnostic sensors for its capability in immobilizing several antigens. Therefore, the growing interest in BC derived materials establishes it as a great promise to enhance the quality and functionalities of the current generation of biomedical materials., (Copyright © 2017 Elsevier B.V. All rights reserved.)

We investigated the hepatoprotective effect of methanolic extract from Maytenus robusta leaves in mice and HepG2 cells. The administration of CCl 4 in mice promoted a deep destruction of the histological lobular structure and increased the alanine aminotransferase (ALT) serum levels by 46.25% compared with the control group (p < 0.05). The M. robusta extract reduced the hepatic histological changes and normalization the ALT levels. The antioxidant effect of M. robusta in liver tissue promoted the reduction in 31.5% on lipoperoxides levels (p < 0.05), increased by 101.5% the reduced glutathione content (p < 0.05) and increased the activity of superoxide dismutase, catalase, and glutathione-S-transferase by 21.3% (p < 0.05), 49.3% (p < 0.05), and 27.6% (p < 0.05), respectively, compared with the vehicle group. Moreover, the extract reduced hepatic inflammation by diminishing myeloperoxidase activity, TNF and interleukin-6 levels by 29.4% (p < 0.05), 46.1% (p < 0.01), and 59.5% (p < 0.0001), respectively, compared with the vehicle group. The viability of HepG2 cells after incubation with CCl 4 was 29.56± 3.07%, whereas the extract (300 μg/mL) restored the viability to 65.27± 8.75% and aspartate aminotransferase levels to 41.82 ± 4.41 U/L. The extract scavenged DPPH (IC 50  = 14.44 μg/mL) and ABTS (IC 50  = 3.00 μg/mL) radicals and did not produce acute toxicity in mice at 2000 mg/kg. In conclusion, was confirmed the hepatoprotective potential of M. robusta by its antioxidant effects., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Core-shell particles were formed by mixing in aqueous solution the neutral polysaccharide xyloglucan (XG) with microgels. The last one was obtained by heating the whey protein β-lactoglobulin (β-LG) in the presence of CaCl 2 . XG adsorbed spontaneously unto the microgels at pH<5.6. The amount of bound XG per protein was determined using a combination of centrifugation and size exclusion chromatography. It increased linearly with increasing XG concentration. The fraction of XG that adsorbed increased with decreasing pH. The formation of the XG shell inhibited large scale flocculation of the particles, that causes precipitation for naked microgels, close to their isoionic point. The thickness of the XG shell was estimated by measurement of the hydrodynamic radius using dynamic light scattering. The extent of binding depended on the pH history during mixing showing that the protein/XG complex was not in thermodynamic equilibrium., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this work, polyethylene glycol (PEG), of tree distinct molar masses (200, 300 and 400 g mol(-1)), was grafted onto mercerized bacterial nanocellulose (BNCm) and applied to produce nanofilms (BNCm-PEG). The products BNCm-PEG were characterized by NMR and thermal analysis. Solid-state NMR and X-ray diffraction analyses exhibited no significant differences in index of BNCm-PEG derivatives compared to BNCm, indicating that grafting reaction did not modify the BNCm crystalline structure. The apparent contact angle of the films showed that BNCm-PEG films exhibited a pronounced increase in the polar components (BNCm: 8.1 mN m(-1) vs BNCm-PEG400: 29.4 mN m(-1)), and a decrease in dispersive components (BNCm: 41.7 mN m(-1) vs BNCm-PEG400: 35.2 mN m(-1)) of the surface free energy. The BNCm-PEG films were more hydrophilic than BNCm and retained the biocompatibility with L929 fibroblast cells culture., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Hydrolysis of xyloglucan from Tamarindus indica and Hymenaea courbaril seeds with endoglucanase (EGII), which randomly breaks the (1→4)-linked β-glycosidic bonds of the polymer chain, was monitored in real time using time-dependent viscometry analysis (TDV). For both samples there was a decrease in the intrinsic viscosity ([η]), viscosity average molar mass (Mv), radius de gyration (Rg) and persistence length (Lp) immediately after the addition of the enzyme. It was observed the formation of oligosaccharides and oligomers composed of ∼2 units, up to 140min. Galactose-containing side chains two positions away from the non-substituted glucose, modulated the action of EGII, and the complete hydrolysis of the XG oligomers occurred after 24h. The results demonstrate for the first time the real-time degradation of xyloglucan as well the macromolecular and oligosaccharide composition during the EGII hydrolysis process., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A novel wound-dressing biodevice, sensitive to lysozyme, an enzyme commonly found at infected skin wounds, was assembled by the layer-by-layer deposition of nanopolymeric chitosan and alginate films onto oxidized bacterial cellulose membranes incorporated with epidermal growth factor (EGF). Distinct EGF release profiles were obtained according to specific stimuli caused by infection. In in vitro conditions simulating noninfected wounds, the EGF rate and burst release effect were reduced by three deposited layers (Mt /M∞ of 0.25 at 3 h) in a process dependent on the porosity of the compact chitosan-alginate complex. The importance of the organized structure was revealed when an infected wound was simulated by adding lysozyme to the release medium, thus inducing the formation of a loosely polyelectrolyte architecture that caused rapid EGF diffusion (Mt /M∞ of 0.75 at 30 min). The results indicate that the nanopolymeric layers were capable of slowly releasing EGF as required for normal wound repair and rapidly undergoing architectural transitions that allow the diffusion of massive amounts of drug to enhance the process of re-epithelialization. In summary, the proposed system comprises the roles of both wound dressing and local delivery mechanism to recognize infections and respond with a burst of EGF release., (© 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.)

The non-flooded upland rainforest fragment in the Federal University of Amazonas Campus is considered one of the world's largest urban tropical woodland areas and Brazil's second largest one in an urban setting. It is located in the city of Manaus, State of Amazonas at 03° 04' 34″ S, 59° 57' 30″ W, in an area covering nearly 800 hectares. Forty-one (41) sand fly species belonging to genus Lutzomyia were found attaining a total of 4662 specimens collected. Lutzomyia umbratilis was the dominant species at all heights, followed by Lutzomyia anduzei and Lutzomyia claustrei. The fauna alpha diversity index showed to be 6.4, which is not much lower than that reported for areas of continuous forest in this Amazonian region. This data provides additional evidence on Phlebotomine sand flies found to transmit Leishmania and other trypanosomatids to humans and other animals circulating in this area. This is the first study being reported on sand flies collected in an urban rainforest fragment in Amazonia., (Copyright © 2013 Elsevier B.V. All rights reserved.)

We compared the structures and rheology of xanthan-galactomannan (X:G) hydrogels with the addition of curcumin in microemulsion (X:GMC) and ethanol (X:GEC). X:GMC hydrogels have gel characteristics and exhibited a significantly higher elastic response than the X:GEC and X:G hydrogels at room temperature, but after heating, an increase in the elastic modulus was observed for the last two systems. The visualization of the hydrogel microstructures by cryo-scanning electronic microscopy revealed pores within the lamellar structure only for X:GMC. In vitro skin permeation tests showed a more pronounced lag time for X:GMC; however, a more efficient permeation from X:GMC than from X:GEC. This study demonstrates that the X:G system is an alternative to traditional gels for the topical applications of hydrophobic drugs., (Copyright © 2012 Wiley Periodicals, Inc.)

In this work, didecyldimethylammonium bromide (DDAB) and 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE) (2.5:1) were used to prepare liposomes coated with polyacrylic acid (PAA) using "in situ" polymerization with 2.5, 5 and 25 mM of acrylic acid (AA). The PAA concentrations were chosen to achieve partially to fully covered capsules, and the polymerization reaction was observed with real-time monitoring using dynamic light scattering (NanoDLS). The DDAB:DOPE liposomes showed stability in the tested temperature range (25-70°C), whereas the results confirmed the success of the polymerization according to superficial charge (zeta potential of +66.7±1.2 mV) results and AFM images. For the liposomes that were fully coated with PAA (zeta potential of +0.3±3.9 mV), cytotoxicity was independent of the concentration of albumin. Cationic liposomes and nanocapsules of the stable liposomes coated with PAA were obtained by controlling the surface charge, which was the most important factor related to cytotoxicity. Thus, a potential, safe drug nanocarrier was successfully developed in this work., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Nanoparticles based on chitosan (Ch) and N-carboxymethylchitosan (N-CMCh) cross-linked with tripolyphosphate (TPP) were developed by co-drying with idebenone in different polymer-to-drug ratios (1.3:1 to 16:1) with 20% (wt/wt) colloidal silicon dioxide and tripolyphosphate (0.2 mg/mL). At high ratios (8:1 and 16:1) the spray-dried powder showed spherical and dense particles with a size close to 1 μm, allowing almost complete drug coating by the polymeric system and a high efficiency of drug incorporation (>90% and >80%, for Ch and N-CMCh, respectively). The nanoparticles showed a 10-fold increase of drug stability in comparison with free drug and preserved antioxidant activity in vitro. Compared with the severely irritative free form of idebenone, the nanoparticle formulation showed decreased mucous membrane irritation. These results revealed the potential of Ch and N-CMCh nanoparticles as carriers for a hydrophobic and irritative drug such as idebenone for topical or nasal use., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Fresh leaves of Vernonia scorpioides are widely used in Brazil to treat a variety of skin disorders. Previous in vivo studies with extracts of this species had also demonstrated a high antitumor potential. This paper reports isolation of four sesquiterpene lactones (hirsutinolides and glaucolides), together with diacetylpiptocarphol, 8-acetyl-13-etoxypiptocarphol, luteolin, apigenin, and ethyl caffeate from fresh leaves and flowers of Vernonia scorpioides. The hypothesis that hirsutinolide 3 is formed during extraction was verified theoretically using Density Functional Theory. The effects of isolated compounds on in vitro tumor cells were investigated, as well as their genotoxicity by means of an in vitro comet assay. The results indicate that glaucolide 2 and hirsutinolide 4 are toxic to HeLa cells. These compounds were genotoxic in vitro, a property that appears to be related to the presence of their epoxy groups, which has been a more reliable indication of toxicity than substitution on C-13 or the presence of alpha,beta-unsaturated keto-groups. These results need to be replicated in vivo in order to ascertain their toxicity., ((c) 2010 Elsevier Ltd. All rights reserved.)