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1.
Sci. agric ; 79(4): e20200235, 2022. tab, graf
Artículo en Inglés | VETINDEX | ID: biblio-1290211

RESUMEN

Hydrogels have potential as soil conditioners due to their high capacity to retain water and mitigate soil salinity. However, investigations under saline conditions are necessary because there are losses in both water absorption and salinity mitigation depending on the composition of hydrogel and ions involved in salinity. In this work, we studied a commercial hydrogel in two experiments. The first experiment was conducted in the laboratory to evaluate the absorption by the hydrogel of water with electrical conductivity (EC) of 0.5, 1.5, 3.0, and 4.5 dS m-1, promoted by NaCl. The second experiment was conducted in a greenhouse in a 2 × 4 factorial scheme (with and without hydrogel × EC of the first experiment). Although salinity reduced water absorption by hydrogel by 84 %, the polymer applied in a sandy soil under saline conditions reduced water losses by 58 %. However, hydrogel did not increase the final soil moisture (~ 0.10 g g-1). The polymer reduced Na+ concentration in leachate from 1,499 to 1,219 mg L-1 at the highest salinity level (4.5 dS m-1), but it increased Na+ soil availability by 0.1 mg kg-1 in comparison with polymer absence. Hydrogel application increased Na+ content in plants from 9 to 13 mg kg-1 at the highest salinity, while K+ content was 10 to 16 mg kg-1 lower than that observed without a polymer. Hydrogel 0.07 % (w/w) reduced maize biomass, indicating damage by monovalent ions, compromising the polymer potential under salinity.


Asunto(s)
Agua , Suelos Salitrosos/análisis , Hidrogeles/análisis , Salinidad , Acrilatos , Acrilamida/análisis
2.
Ci. Rural ; 50(6): e20190176, May 11, 2020. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-28381

RESUMEN

Dairy desserts containing Caesalpinia pulcherrima seed galactomannan were evaluated to determine their static and dynamic rheological behaviors. Variations in consistency index (k), flow behavior (n), yield stress and thixotropy of the desserts indicated that the galactomannan caused an increase in the shear stress and apparent viscosity of the system. All samples exhibited shear-thinning behavior with flow behavior index values (n) between 0.06 and 0.37. Dynamic rheological behavior was evaluated for MD (high solid levels) and MD/2 (half the amount of solids) groups, and both G and G moduli were depended on the frequency. The MD and MD/2 groups showed variations in the elastic modulus (G) throughout the temperature range (mainly at 50 °C), showing greater sensitivity at high temperatures. C. pulcherrima galactomannan was able to promote synergism with starch, milk protein and sucrose and to improve the development of stronger and more resistant gels.(AU)


Sobremesas lácteas contendo galactomanana de semente de Caesalpinia pulcherrima tiveram suas propriedades reológicas estáticas e dinâmicas avaliadas. As variações nos índices de consistência (K) e comportamento de fluxo (n), assim como na tensão inicial de fluxo e na tixotropia das sobremesas mostraram o efeito da galactomanana sobre a tensão de cisalhamento e viscosidade aparente dos sistemas lácteos. Todas as sobremesas exibiram comportamento pseudoplástico, com índices de comportamento de fluxo (n) variando entre 0,06 e 0,37. A reologia dinâmica dos grupos MD (alto teor de sólidos) e MD/2 (metade do teor de sólidos), mostrou G > G e módulos dependentes da frequência e da temperatura. Alterações químicas nos componentes das sobremesas foram observadas a 50° C em virtude da maior sensibilidade dos valores de G e G a partir dessa temperatura. A galactomanana de C. pulcherrima contribuiu para o desenvolvimento de géis mais fortes e resistentes nas sobremesas lácteas, bem como mostrou sinergismo com amido, proteína do leite e sacarose.(AU)


Asunto(s)
Caesalpinia , Reología , Productos Lácteos
3.
Colloids Surf B Biointerfaces ; 189: 110852, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32062110

RESUMEN

Nile tilapia skin, an abundant waste from fish processing, can be used for collagen extraction, which has a high aggregated value for biomedical applications. Collagen extraction was conducted under different reaction conditions (time, temperature, and concentration of acetic acid) in order to optimize the yield without compromising the integrity of the collagen. Temperature and time were responsible for increased yield. The extraction at 4 and 20 °C produced the acid-solubilized collagen (ASC) with the intact triple helix and was analysed by Fourier-transform infrared spectroscopy (FT-IR) and circular dichroism (CD). The optimized ASC (which used 0.35 mol/L of acetic acid at 20 °C) was consumed to obtain for the first-time fish-based hydrogels with hyaluronic acid (HA) crosslinked with 1-ethyl-3-(3-dimethylaminopropryl carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The hydrogel was characterized by FT-IR, rheology, swelling, and scanning electron microscopy (SEM), confirming that cross-linking was accomplished. It possesses a robust organized network, swells 255 % in PBS and bears interconnected pores with a diameter in the range of 10-100 µm. Until now, col-HA hydrogels crosslinked with EDC/NHS have not been reported in literature with collagen from Nile Tilapia skin. Fish collagen can be a better option than those from land-based animals (cow and pig).


Asunto(s)
Ácido Hialurónico/química , Hidrogeles/química , Piel/química , Animales , Cíclidos , Colágeno/química , Colágeno/aislamiento & purificación , Tamaño de la Partícula , Propiedades de Superficie
4.
J Ethnopharmacol ; 248: 112303, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-31614204

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: There are many reports of pharmacological activities of extracts and fractions of different vegetable-derived products in the scientific literature and in folk medicine. Ethnopharmacological use of these products by various communities continues to be extensively explored, and they account for more than half of all medications used worldwide. Polysaccharides (PLS) extracted from plants such as Morinda Citrifolia Linn present therapeutic potential in treatment of inflammatory bowel diseases (IBD) such as ulcerative colitis (UC). AIM OF THE STUDY: To evaluate the anti-inflammatory action of Noni-PLS against the intestinal damage in UC induced by acetic acid in mice. MATERIALS AND METHODS: In acetic acid-induced colitis, the mice were treated intraperitoneally (ip) with Noni-PLS (0.1, 0.3, and 3.0 mg/kg) or subcutaneously (sc) with dexamethasone (2.0 mg/kg) 30 min before euthanasia to determine the best dose of Noni-PLS with an anti-inflammatory effect in the course of UC. The colonic tissue samples were collected for macroscopic, wet weight, microscopic and biochemical (myeloperoxidase (MPO), glutathione (GSH), malondialdehyde (MDA), nitrate/nitrite (NO3/NO2), cytokines, cyclooxygenase (COX-2) and inducible nitric oxide (iNOS)) analyses. RESULTS: Treatment with Noni-PLS reduced the intestinal damage induced by acetic acid as it reduced macroscopic and microscopic scores and the wet weight of the colon. In addition, MPO activity and levels of GSH, MDA, NO3/NO2, pro-inflammatory cytokines, and COX-2 expression reduced. CONCLUSIONS: This study suggests that Noni-PLS exhibits anti-inflammatory action against intestinal damage by reducing inflammatory cell infiltration, oxidative stress, pro-inflammatory action of cytokines, COX-2 and iNOS expression in the inflamed colon. Noni-PLS shows therapeutic potential against inflammatory disorders like UC.


Asunto(s)
Antiinflamatorios/uso terapéutico , Colitis/tratamiento farmacológico , Morinda , Polisacáridos/uso terapéutico , Ácido Acético , Animales , Antiinflamatorios/farmacología , Colitis/inducido químicamente , Colitis/metabolismo , Colitis/patología , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Ciclooxigenasa 2/metabolismo , Frutas , Glutatión/metabolismo , Interleucina-1beta/metabolismo , Masculino , Malondialdehído/metabolismo , Ratones , Nitratos/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Nitritos/metabolismo , Peroxidasa/metabolismo , Polisacáridos/farmacología , Factor de Necrosis Tumoral alfa/metabolismo
5.
Adv Rheumatol ; 60: 26, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1130806

RESUMEN

Abstract Background: Injection of Hylan G-F20 (HY) into joints may provoke local flares, which mechanisms may involve reaction to protein contaminants. We have previously developed a protein-free saline-soluble galactomannan derived from guar gum (GM) that displays both analgesia and chondroprotection in experimental osteoarthritis (OA). We now demonstrate that both GM and Hylan G-F20 (HY) promote mild synovitis with cytokine release after intra-articular injection. Methods: Mice received 100 μg/25 μL GM or HY or saline into the knees. Joint pain was evaluated using von Frey test; cell influx, interleukin (IL)-1, IL-6, and CXCL-1 (pg/mL) levels were assessed in joint lavage at 6 h. Synovia were excised for histopathology. Results: Neither GM nor HY after being given into mice knee joints induced pain albeit promoting mild cell influx into joint washings as well as mild synovitis at histology, with no damage to the underlying cartilage. HY but not GM promoted IL-1 release into mice joints. Both compounds induced IL-6 and CXCL-1 release. Conclusion: Intra-articular injection of HY or GM promote acute transient synovitis whilst not provoking detectable significant joint damage. Local administration of these polysaccharides induces acute intra-articular release of inflammatory cytokines, which may account for joint flares following viscosupplementation.(AU)


Asunto(s)
Animales , Ratones , Osteoartritis/fisiopatología , Polisacáridos/administración & dosificación , Viscosuplementación/instrumentación , Ácido Hialurónico/administración & dosificación
6.
Ciênc. rural (Online) ; 50(6): e20190176, 2020. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1133265

RESUMEN

ABSTRACT: Dairy desserts containing Caesalpinia pulcherrima seed galactomannan were evaluated to determine their static and dynamic rheological behaviors. Variations in consistency index (k), flow behavior (n), yield stress and thixotropy of the desserts indicated that the galactomannan caused an increase in the shear stress and apparent viscosity of the system. All samples exhibited shear-thinning behavior with flow behavior index values (n) between 0.06 and 0.37. Dynamic rheological behavior was evaluated for MD (high solid levels) and MD/2 (half the amount of solids) groups, and both G' and G'' moduli were depended on the frequency. The MD and MD/2 groups showed variations in the elastic modulus (G') throughout the temperature range (mainly at 50 °C), showing greater sensitivity at high temperatures. C. pulcherrima galactomannan was able to promote synergism with starch, milk protein and sucrose and to improve the development of stronger and more resistant gels.


RESUMO: Sobremesas lácteas contendo galactomanana de semente de Caesalpinia pulcherrima tiveram suas propriedades reológicas estáticas e dinâmicas avaliadas. As variações nos índices de consistência (K) e comportamento de fluxo (n), assim como na tensão inicial de fluxo e na tixotropia das sobremesas mostraram o efeito da galactomanana sobre a tensão de cisalhamento e viscosidade aparente dos sistemas lácteos. Todas as sobremesas exibiram comportamento pseudoplástico, com índices de comportamento de fluxo (n) variando entre 0,06 e 0,37. A reologia dinâmica dos grupos MD (alto teor de sólidos) e MD/2 (metade do teor de sólidos), mostrou G' > G'' e módulos dependentes da frequência e da temperatura. Alterações químicas nos componentes das sobremesas foram observadas a 50° C em virtude da maior sensibilidade dos valores de G' e G" a partir dessa temperatura. A galactomanana de C. pulcherrima contribuiu para o desenvolvimento de géis mais fortes e resistentes nas sobremesas lácteas, bem como mostrou sinergismo com amido, proteína do leite e sacarose.

7.
Carbohydr Polym ; 149: 391-8, 2016 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-27261763

RESUMEN

A polysaccharide was extracted from the roots of Pombalia calceolaria, a plant used in folk medicine in Northeastern Brazil, by decoction followed by precipitation with methanol, yielding a concentration of 13.0% w/w, and purification with acetone. The molar mass peak was estimated to be 4.0×10(3)Da using gel permeation chromatography (GPC). Polarized light photomicrography of histological sections revealed the presence of inulin in the cortical parenchyma. The chemical composition of inulin was identified by 1D and 2D NMR and FT-IR spectroscopy and the findings were compared with the literature. This is the first time inulin has been identified on FT-IR and NMR for the species Pombalia calceolaria.


Asunto(s)
Inulina/análisis , Raíces de Plantas/química , Violaceae/química , Inulina/química , Inulina/aislamiento & purificación
8.
Clin Rheumatol ; 28(2): 109-17, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18791656

RESUMEN

Evidence that combined glucosamine sulfate and chondroitin sulfate (Gluchon) or isolated glucosamine (Glu) modifies joint damage in osteoarthritis (OA) is still lacking. We studied joint pain and cartilage damage using the anterior cruciate ligament transection (ACLT) model. Wistar rats were subjected to ACLT of the right knee (OA) or sham operation. Groups received either Glu (500 mg/kg), Gluchon (500 mg/kg glucosamine +400 mg/kg chondroitin) or vehicle (non-treated--NT) per os starting 7 days prior to ACLT until sacrifice at 70 days. Joint pain was evaluated daily using the rat-knee joint articular incapacitation test. Structural joint damage was assessed using histology and biochemistry as the chondroitin sulfate (CS) content of cartilage by densitometry (microgram per milligram dried cartilage), comparing to standard CS. The molar weight (Mw) of the CS samples, used as a qualitative biochemical parameter, was obtained by comparing their relative mobility on a polyacrylamide gel electrophoresis to standard CS. Gluchon, but not Glu, significantly reduced joint pain (P < 0.05) compared to NT. There was an increase in CS content in the OA group (77.7 +/- 8.3 microg/mg) compared to sham (53.5 +/- 11.2 microg/mg) (P < 0.05). The CS from OA samples had higher Mw (4:62 +/- 10(4) g/mol) compared to sham (4:18 +/- 0.19 x 10(4) g/mol) (P < 0.05). Gluchon administration significantly reversed both the increases in CS content (54.4 +/- 12.1 microg/mg) and Mw (4:18 +/- 0.2 x 10(4) g/mol) as compared to NT. Isolated Glu decreased CS content though not reaching statistical significance. Cartilage histology alterations were also significantly prevented by Gluchon administration. Gluchon provides clinical (analgesia) and structural benefits in the ACLT model. This is the first demonstration that biochemical alterations occurring in parallel to histological damage in OA are prevented by Gluchon administration.


Asunto(s)
Sulfatos de Condroitina/uso terapéutico , Glucosamina/uso terapéutico , Osteoartritis de la Rodilla/tratamiento farmacológico , Osteoartritis de la Rodilla/patología , Animales , Ligamento Cruzado Anterior/cirugía , Artralgia/tratamiento farmacológico , Artralgia/etiología , Artralgia/patología , Cartílago Articular/patología , Modelos Animales de Enfermedad , Quimioterapia Combinada , Masculino , Osteoartritis de la Rodilla/complicaciones , Ratas , Ratas Wistar
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