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1.
Carbohydr Polym ; 327: 121678, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38171663

ABSTRACT

Mushroom polysaccharides consist of a unique set of polymers that arrive intact in the human large intestine becoming available for fermentation by resident gut bacteria with potential benefits to the host. Here we have obtained four glucans from two mushrooms (Pholiota nameko and Pleurotus pulmonarius) under different extraction conditions and their fermentation profile by human gut bacteria in vitro was evaluated. These glucans were isolated and characterized as (1 â†’ 3),(1 â†’ 6)-ß-D-glucans varying in branching pattern and water-solubility. An aliquot of each (1 â†’ 3),(1 â†’ 6)-ß-D-glucan was subjected to controlled smith degradation process in order to obtain a linear (1 â†’ 3)-ß-D-glucan from each fraction. The four ß-D-glucans demonstrated different water solubilities and molar mass ranging from 2.2 × 105 g.mol-1 to 1.9 × 106 g.mol-1. In vitro fermentation of the glucans by human gut microbiota showed they induced different short chain fatty acid production (52.0-97.0 mM/50 mg carbohydrates), but an overall consistent high propionate amount (28.5-30.3 % of total short chain fatty acids produced). All glucans promoted Bacteroides uniformis, whereas Anaerostipes sp. and Bacteroides ovatus promotion was strongly driven by the ß-D-glucans solubility and/or branching pattern, highlighting the importance of ß-D-glucan discrete structures to their fermentation by the human gut microbiota.


Subject(s)
Gastrointestinal Microbiome , beta-Glucans , Humans , Glucans/chemistry , beta-Glucans/metabolism , Fermentation , Fatty Acids, Volatile , Water
2.
J Dairy Res ; : 1-8, 2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35225181

ABSTRACT

Caseinomacropeptide (CMP) is derived from the chymosin cleavage of κ-casein during cheese production. This study developed gels from CMPs, which were isolated by different ultrafiltration systems, and whey protein isolate (WPI), and studied their rheological and ultrastructural characteristics. The 30% WPI gel showed high elastic modulus (G') values and stronger structure than the other samples with CMP. Another gel, with 50% protein, 30% WPI and 20% CMP sample isolated from the 30 kDa retentate, had a weaker structure and lower G' value. The third gel, with 30% WPI and 20% CMP sample from the 5 kDa retentate derived from the 30 kDa retentate, presented intermediate structural strength. Despite the increase in protein concentration from the addition of CMP, there was a decrease in the strength of the gel network. Different CMP isolation processes also contributed to differences in the microscopic analysis of gel structures with the same protein content.

3.
Int J Biol Macromol ; 165(Pt A): 713-721, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-33011261

ABSTRACT

The interaction between galactomannans, guar gum (GG) with sodium lauryl ether sulphate (SLES) was demonstrated using conductometric, tensiometric, pyrene probe and 1H 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.


Subject(s)
Galactans/chemistry , Mannans/chemistry , Plant Gums/chemistry , Sodium Dodecyl Sulfate/chemistry , Surface-Active Agents/chemistry , Galactose/analogs & derivatives
4.
Int J Biol Macromol ; 162: 599-608, 2020 Nov 01.
Article in English | MEDLINE | ID: mdl-32565303

ABSTRACT

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 (NaSO3- 21.0%; COO- 1.81 mmol·g-1; Mw 18 kg·mol-1) had a more rigid and constrained backbone than C3 (NaSO3- 21.0%; COO- 1.81 mmol·g-1; Mw 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 (NaSO3- 14.1%; COO- 1.23 mmol·g-1; Mw 8.1 kg·mol-1) had higher activity than F2 (NaSO3- 20.6.%; COO- 0.36 mmol·g-1; Mw 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.


Subject(s)
Anticoagulants , Ulva/chemistry , Anticoagulants/chemistry , Anticoagulants/isolation & purification , Anticoagulants/pharmacology , Humans , Molecular Conformation , Molecular Weight , Partial Thromboplastin Time
5.
Carbohydr Polym ; 230: 115562, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31887918

ABSTRACT

This work describes the production of polysaccharide multilayer capsules to control the release of Eugenol (Eug) and enabling its use as an antimicrobial agent. For this propose, oil-in-water nanoemulsions of sodium dodecyl sulfate were coated with alternating depositions of chitosan and carboxymethylcellulose using the Layer-by-Layer (LbL) technique, resulting in capsules containing 1-5 layers. The average size ranged from 188 ±â€¯30 (LbL1) to 1415 ±â€¯517 nm (LbL5). The maximum incorporation efficiency was 70.8 ±â€¯2.7 % for Eug-SDS-LbL1. The initial burst releases decreased in proportion to the increase in the number of polysaccharide layers (22.3 ±â€¯3.1 %-12.8 ±â€¯1.6 %), and are influenced by the pH. These systems exhibited antifungal activity against Aspergillus niger, Trichoderma sp, Gliocladium sp, and Candida albicans, and Eug minimum inhibitory concentrations were lower as compared to those of the free agent. Therefore, these capsules represent promising antifungal materials for application in various fields.


Subject(s)
Anti-Infective Agents/chemistry , Capsules/chemistry , Eugenol/chemistry , Polysaccharides/chemistry , Anti-Infective Agents/pharmacology , Aspergillus/drug effects , Aspergillus/pathogenicity , Candida albicans/drug effects , Candida albicans/pathogenicity , Capsules/pharmacology , Chitosan/chemistry , Eugenol/pharmacology , Microbial Sensitivity Tests , Polysaccharides/pharmacology , Sodium Dodecyl Sulfate/chemistry
6.
Carbohydr Polym ; 200: 353-360, 2018 Nov 15.
Article in English | MEDLINE | ID: mdl-30177176

ABSTRACT

Differences in anomericity and in the branching degree of glucans lead to characteristic intermolecular association that influences their solubility in water or other solvents. A simple purification approach, based on the glucan solubility in aq. 0.1 M NaOH solution, was applied for the separation of mixed water-insoluble α-D-glucans from ß-D-glucans extracted from fruiting bodies of Fomitopsis betulina, which is an underexploited medicinal mushroom. The results indicated that the ß-D-glucan is constituted by (1→3)-linked ß-D-Glcp units substituted at O-6 by non-reducing ß-D-Glcp and (1→6)-linked ß-D-Glcp units, while the α-D-glucan has a linear (1→3)-linked glucan structure. Thus, the 0.1 M NaOH treatment proved to be a simple, efficient and low-cost purification method for separation of water-insoluble glucans with different anomeric configurations and degree of branching that were interacting by intermolecular forces.


Subject(s)
Coriolaceae/chemistry , Glucans/chemistry , Water/chemistry , Carbohydrate Sequence , Solubility , Stereoisomerism
7.
Sci Rep ; 8(1): 10677, 2018 07 16.
Article in English | MEDLINE | ID: mdl-30013110

ABSTRACT

As part of efforts to reduce pressure on the Amazon and other biomes, one approach considered by Brazilian authorities and scientists is more intensive use of the soils of the interior of the northeast of the country, which are generally sandy, with low contents of organic matter and low water holding capacity and are frequently affected by severe droughts. In this work, biochars produced from waste biomasses were tested for the improvement of these soils. The highest BET (Brunauer-Emmett-Teller) specific surface areas were observed for all biochars. In the pH range studied, the water hyacinth plants (WH) sample showed the most negative zeta potentials, as well as the highest water holding capacity (WHC) values, while the zeta potentials of two quartzarenic neosol soils were consistent with their WHC values. The results suggested that despite the effect of porosity on water retention, the zeta potential could be associated with the presence of negative charges by which hydrated cationic counterions were absorbed and retained. The surface energy and its polar and dispersive components were associated with water retention, with sugar cane bagasse, orange peel, and water hyacinth biochars presenting higher SE values and larger polar components.

8.
Carbohydr Polym ; 197: 631-640, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-30007656

ABSTRACT

Native (F2) and carboxyl-reduced (R) ulvans from Ulva fasciata were sequentially oxidized with periodate-chlorite affording the polycarboxyl ulvans C1, C2 and C3 (1.20, 1.41 and 1.81 mmol g-1 of COOH, respectively; 19.7, 21.3 and 21.0% of NaSO3, respectively) and R-C3 (1.86 mmol g-1 of COOH; NaSO3 = 22.7%), respectively. APTT assay (polysaccharide fractions at 150 µg mL-1) showed clotting time of 45.6 s for F2 fraction. For polycarboxyl ulvans C1, C2, C3 and R-C3 the clotting times were 101.0, 122.2, 222.0 and 227.0 s, respectively. Comparison of the APTT assay results using ulvans chemically modified by carboxyl-reduction, desulfation, periodate oxidation and/or chlorite oxidation showed the anticoagulant activity of polycarboxyl ulvans is dependent of the sulfate groups present in the native polymer. In addition, the increase of the anticoagulant activity was accompanied by the increasing of the carboxyl groups and the content of this acidic substituent seems to be more important than its positioning.


Subject(s)
Anticoagulants/pharmacology , Blood Coagulation Factors/antagonists & inhibitors , Chlorides/pharmacology , Periodic Acid/pharmacology , Polysaccharides/pharmacology , Anticoagulants/chemistry , Chlorides/chemistry , Dose-Response Relationship, Drug , Molecular Conformation , Oxidation-Reduction , Periodic Acid/chemistry , Polysaccharides/chemistry
9.
Carbohydr Polym ; 170: 140-147, 2017 Aug 15.
Article in English | MEDLINE | ID: mdl-28521979

ABSTRACT

Polysaccharide TEMPO-oxidation was monitored using automatic continuous online monitoring of polymerization reactions (ACOMP). The products of oxidation, obtained at different pHs (9, 7 and 5) and different concentrations of catalyst TEMPO, were evaluated by Automatic Continuous Mixing (ACM) and Size Exclusion Chromatography (SEC). The degree of oxidation was higher at pH 9 and polysaccharide degradation was observed under different pH conditions, but was much higher without catalyst TEMPO. The rate constant (k) was dependent on reaction pH and TEMPO concentration. The amount of -COOH per g of polysaccharide, at pH 9, in the presence and absence of TEMPO was different, 0.215 and 0.395mmolg-1, respectively. This suggested a secondary and non-selective polysaccharide oxidation occurring at a lower rate in the absence of catalyst. TEMPO protects the polysaccharide from degradation caused by secondary oxidant species, acting as a catalyst and "sacrificial molecule" at higher concentrations.


Subject(s)
Cyclic N-Oxides , Polysaccharides/chemistry , Catalysis , Oxidation-Reduction , Polymerization
10.
Int J Biol Macromol ; 86: 599-605, 2016 May.
Article in English | MEDLINE | ID: mdl-26845482

ABSTRACT

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.


Subject(s)
Bacteria/chemistry , Cellulose/chemistry , Hydrophobic and Hydrophilic Interactions , Polyethylene Glycols/chemistry , Animals , Cell Line , Materials Testing , Mice , Molecular Weight , Nanostructures/chemistry , Polymerization
11.
Langmuir ; 32(5): 1227-32, 2016 Feb 09.
Article in English | MEDLINE | ID: mdl-26757399

ABSTRACT

The phase diagram of mixtures of xyloglucan (XG) and amylopectin (AMP) in aqueous solution is presented. Water-in-water emulsions prepared from mixtures in the two-phase regime were studied in detail, and the interfacial tension was determined. It is shown that the emulsions can be stabilized by addition of ß-lactoglobulin microgels (ßLGm), but only at pH ≤ 5.0. Excess ßLGm preferentially entered the AMP phase at pH > 5.0 and the XG phase at lower pH. The inversion was caused by adsorption of XG onto ßLGm that started below pH 5.5. It is shown that modification of the surface of particles by coating with polysaccharides is a potential lever to control stabilization of water-in-water emulsions.


Subject(s)
Amylopectin/chemistry , Glucans/chemistry , Lactoglobulins/chemistry , Xylans/chemistry , Emulsions , Fluorescein-5-isothiocyanate , Gels , Hydrogen-Ion Concentration , Rhodamines , Surface Tension , Water/chemistry
12.
Basic Clin Pharmacol Toxicol ; 113(5): 307-15, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23763911

ABSTRACT

Vernonia scorpioides (Lam.) Pers., popularly known as Enxuga, Erva-de-São Simão and Piracá, has been used in folk medicine for its anti-inflammatory, wound healing and antimicrobial properties. Two polyacetylenes, 5-octa-2,4,6-triynyl-furan-2(5H)-one (1) and 8'-hydroxy 3-4 dihydrovernoniyne (2), were isolated from the dichloromethane extract fraction of V. scorpioides. In this study, polyacetylene 1 demonstrated a more potent cytotoxic activity than 2 in the tumour cell lines examined, and cytotoxicity was found to be comparable to a commercial drug (p > 0.05) in melanoma cells. No significant cytotoxic effect was observed in normal cell lines. Furthermore, polyacetylene 1 induced an in vitro increase in caspase-3 activity in B16F10 cells. When polyacetylene 1 was administered intraperitoneally (i.p.) in mice, a reduction in solid tumour volume and metastasis was observed in mice injected with B16F10 cells. An increase in locomotor activity was also observed in mice with solid tumours, and an inhibition of mechanical hypersensitivity was observed in a mouse model of metastasis. Notably, no significant morphological change was observed in several organs harvested from the treated mice. In conclusion, in vitro and in vivo anticancer activity of polyacetylene 1 was consistently observed and involved the induction of apoptosis by the activation of caspase-3. The anticancer activity demonstrated by polyacetylene 1, together with the absence of preliminary toxicological effects, represents a new and interesting option for the management of neoplastic disease.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Furans/pharmacology , Plant Extracts/pharmacology , Polyynes/pharmacology , Vernonia/chemistry , Animals , Apoptosis/drug effects , Caspase 3/genetics , Caspase 3/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Disease Models, Animal , Male , Methylene Chloride/chemistry , Mice , Mice, Inbred C57BL
13.
Carbohydr Polym ; 93(2): 484-91, 2013 Apr 02.
Article in English | MEDLINE | ID: mdl-23499087

ABSTRACT

Guar gums of two different commercial sources were successfully electrospun on both mica and copper tape at several concentrations starting from 1% (w/w). The electrospun fibers formed with the raw materials were not uniform and presented aggregates and beads within the fibers. Two different purification procedures and a filtration sequence with different pore size membranes were applied to enhance galactomannan solution homogeneity and solubility. The consequence was improved fiber morphology. We observed that the precipitation step, within the purification procedure, produced changes in the molar mass distribution and yielded different fiber diameter. Furthermore, spherical aggregates between fibers and within them disappeared after the sequential filtration. The resulting electrospun fiber diameter decreased with membrane pore diameter reduction. We conclude that the filtration process is responsible for molecular disentanglement, as well as disaggregation, which leads to improved electrospun galactomannan fiber morphology.


Subject(s)
Filtration/methods , Galactans/chemistry , Galactans/isolation & purification , Mannans/chemistry , Mannans/isolation & purification , Plant Gums/chemistry , Plant Gums/isolation & purification , Aluminum Silicates/chemistry , Chemical Phenomena , Chemical Precipitation , Chromatography, Gel , Copper/chemistry , Membranes, Artificial , Microscopy, Atomic Force , Molecular Conformation , Nanofibers/analysis , Nanofibers/chemistry , Plant Proteins/analysis , Plant Proteins/chemistry , Porosity , Solubility
14.
J Pharm Sci ; 101(7): 2457-67, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22549766

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/administration & dosage , Curcumin/administration & dosage , Drug Carriers/chemistry , Hydrogels/chemistry , Mannans/chemistry , Polysaccharides, Bacterial/chemistry , Administration, Cutaneous , Animals , Antineoplastic Agents/pharmacokinetics , Curcumin/pharmacokinetics , Galactose/analogs & derivatives , Rheology , Skin/metabolism , Skin Absorption , Swine
15.
Phytochemistry ; 71(13): 1539-44, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20599237

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Lactones/chemistry , Sesquiterpenes/isolation & purification , Sesquiterpenes/pharmacology , Vernonia/chemistry , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/toxicity , Cell Line, Tumor , Ethanol/chemistry , Flowers/chemistry , Humans , Magnetic Resonance Spectroscopy , Mice , Models, Molecular , Molecular Conformation , Mutagenicity Tests , Plant Extracts/chemistry , Plant Leaves/chemistry , Sesquiterpenes/chemistry , Sesquiterpenes/toxicity
16.
Nanomedicine ; 6(6): 745-52, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20599528

ABSTRACT

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.


Subject(s)
Antioxidants/chemistry , Chitosan/chemistry , Drug Carriers/chemistry , Nanoparticles/chemistry , Ubiquinone/analogs & derivatives , Microscopy, Electron, Scanning , Nanoparticles/ultrastructure , Particle Size , Spectrophotometry, Infrared , Ubiquinone/chemistry
17.
Bioresour Technol ; 99(7): 2659-63, 2008 May.
Article in English | MEDLINE | ID: mdl-17574847

ABSTRACT

Copaifera langsdorfii (Desf.) Kuntze (copaiba) seeds are abundantly produced and have not yet been characterized. The seed oil presents a characteristic odor of coumarin (250.1+/-6.57 mg/g determined through LC). The fatty acid composition of the oil was determined through CG/FID, being 45.3% linoleic acid, 32.3% monounsaturated, and 22.4% saturated fat. For the lipid-free seeds, the total carbohydrate, protein and moisture were 75.4%, 6.8% and 14.8%, respectively. The C. langsdorfii xyloglucan had an intrinsic viscosity of 804 mL/g, and the average molar mass (Mw) was 7.82 x 10(5)g/mol and Rg of 65 nm. The degree of polydispersion was 1.7, indicating the polydisperse family of polysaccharides. Its homogeneity, low degree of polymer contaminants and high intrinsic viscosity and molecular mass, represent good potential as a thickening agent. The presence of coumarin and xyloglucan as major components of C. langsdorfii seeds denotes its potential for use in the cosmetic or pharmaceutical industries.


Subject(s)
Fabaceae/embryology , Plant Oils/chemistry , Seeds/chemistry , Chromatography, Liquid , Fabaceae/chemistry
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