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Resumen: Los productos acuáticos reestructurados se procesan principalmente a partir de especies de pescado infravaloradas, recortes de filetes o subproductos de especies de pescado no comerciales. Una de las pesquerías subvaloradas en el sur de México, es la del macabil (Albula vulpes). El objetivo de este estudio fue evaluar el efecto de la adición de harinas no convencionales y la reducción del nivel de cloruro de sodio en las propiedades mecánicas y funcionales de productos reestructurados de macabil. Se elaboraron reestructurados de macabil para analizar las muestras con harina de amaranto (HA) o harina de grillo (HG) doméstico (0 %, 5 % y 10 %) y tres niveles de sal (0 %, 1 % y 2 %). Se evaluó la pérdida de agua por cocción, la cantidad de agua extraíble y la textura de los geles. El uso de ambas harinas no convencionales disminuyó la pérdida de agua por cocción entre un 49.09 % y 61.97 %, con 1 % de sal. La adición de sal redujo el agua extraíble del reestructurado. Los valores de dureza variaron (P < 0.05) entre tratamientos. La mayor dureza se obtuvo en los tratamientos con HA al 10 % y sal al 1 % (64.55 N) y con HG al 10 % y sal al 2 % (63.50 N). La cohesividad varió de 0.53 a 0.71 (adimensional) en los tratamientos con 1 % y 2 % de sal, indicando pocos cambios en la estructura interna por efecto de los aditivos. Las harinas no convencionales permitieron la gelificación proteica, formando reestructurados con propiedades texturales adecuadas para un producto cárnico. La adición del 10 % de HG común o de HA y 1 % de uso de sal, en la formulación de reestructurados de pescado, ofrece una alternativa saludable en el desarrollo de alimentos de pescado.
Abstract: Restructured seafood products are primarily processed from undervalued fish species, fillet trimmings, or byproducts of non-commercial fish species. One of the underrated fisheries in southern Mexico is that of the bonefish (Albula vulpes). The objective of this study was to evaluate the effect of adding non-conventional flours and reducing the sodium chloride level on the mechanical and functional properties of restructured bonefish products. Bonefish restructured products were prepared to analyze samples with (0 %, 5 %, and 10 %) amaranth flour (AF) or cricket flour (CF) and three levels of salt (0 %, 1 % and 2 %). The cooking water loss, the amount of extractable water and the texture from gels were evaluated. The use of both non-conventional flours reduced cooking water loss by 49.09 % to 61.97 % with 1 % salt. The addition of salt reduced the extractable water in the restructured product. Hardness values varied (P < 0.05) among treatments. The highest hardness was obtained in treatments with 10 % AF and 1 % salt (64.55 N) and with 10 % CF and 2 % salt (63.50 N). Cohesiveness ranged from 0.53 to 0.71 (dimensionless) in treatments with 1 % and 2 % salt, indicating minimal changes in internal structure due to additives. Non-conventional flours allowed for protein gelation, forming restructured products with suitable textural properties for a meat product. The addition of 10 % CF or AF and 1 % salt in fish restructured product formulation offers a healthy alternative in the development of fish-based foods.
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Arabinoxylans (AXs) are compounds with high nutritional value and applicability, including prebiotics or supplementary ingredients, in food manufacturing industries. Unfortunately, the recovery of AXs may require advanced separation and integrated strategies. Here, an analysis of the emerging techniques to extract AXs from cereals and their by-products is discussed. This review covers distinct methods implemented over the last 2-3 years, identifying that the type of method, extraction source, AX physicochemical properties and pre-treatment conditions are the main factors influencing the recovery yield. Alkaline extraction is among the most used methods nowadays, mostly due to its simplicity and high recovery yield. Concurrently, recovered AXs applied in food applications is timely reviewed, such as potential bread ingredient, prebiotic and as a wall material for probiotic encapsulation, in beer and non-alcoholic beverage manufacturing, complementary ingredient in bakery products and cookies, improvers in Chinese noodles, 3D food printing and designing of nanostructures for delivery platforms.
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Fibras na Dieta , Probióticos , Fibras na Dieta/análise , Prebióticos/análise , Xilanos/químicaRESUMO
Research on larval rearing and nutrition of tephritid flies on artificial diets is key for the sterile insect technique. Here, we examined the effects of the type of gel (calcium alginate, agar, or carrageenan), at varying percentages in artificial diets for the polyphagous pest Anastrepha ludens, on the physicochemical and nutritional traits of the diets, and the effects of the type of gel, the gel content and the larval density (larvae/g of diet) used in production, quality parameters for mass-reared tephritids, diet removal (an indirect estimation of diet consumption), and nutritional traits of flies. Regardless of the gel content, calcium alginate diets were firmer and more resistant to penetration than the agar and carrageenan diets. The larval recovery, pupation, pupal weight, and flight ability of A. ludens were lower in calcium alginate diets than in agar and carrageenan diets. Diet removal was higher in calcium alginate diets; however, low levels of ammonium and high levels of uric acid in excretions from larvae on these diets suggest an alteration in protein metabolism. The firmness and penetration resistance characteristics of calcium alginate diets may have limited movement and feeding of larvae, but this could be overcome by the collective feeding of large groups of larvae. Our findings provide insights into the mechanism governing gel-diet rearing systems for A. ludens.
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Adding gelling agents to convert the liquid state of the semen extender to a solid state allows for an increased sperm life span. Gelatin and alginate have been used to study the effects of gelling agents on sperm quality. However, there are other gelling agents that have not been studied, such as agar. In addition, studying different sources of gelling agents or the effect of mixing more than one gelling agent with semen extenders on sperm fertility has received little attention. Therefore, the objective of this study was to evaluate the effect of adding agar and a mixture of gelling agents from different sources to semen extender on ram sperm traits and fertility. The first trial evaluated the effect of the addition of 2.5-3 mg mL-1 of gelatin mixed with 0.5-20 mg mL-1 of agar or alginate to ram semen extender on sperm (motility, progressive motility, live/dead, membrane integrity) and semen (pH) characteristics. The response variables were evaluated 1, 72 and 144 h after storage at 4°C. In the second trial, two sources (feed grade and bacteriological) of gelatin and agar were evaluated on the response variables as in Trial 1. In trial 3, a total of 34 ewes were inseminated with doses supplemented (n = 17) with or without (n = 17) agar and gelatin. The pregnancy rate was diagnosed 40 days after insemination. In general, adding agar and gelatin improves (p < .05) sperm motility, membrane integrity and the ratio of live sperm after 144 h of storage compared to the Control group, regardless of the source (bacteriological or feed grade). However, the pregnancy rate in ewes was not influenced (p ≥ .05) by semen doses stored with agar and gelatin. In conclusion, the addition of agar and gelatin preserves ram sperm motility and membrane integrity after 144 of storage at 4°C without affecting the pregnancy rate in inseminated ewes.
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The consumption of plant proteins is increasing worldwide. These proteins have an important role in human nutrition as well as in the technological properties of foods. Thus, there is a great interest in exploring new sources of plant proteins, such as macauba (Acrocomia aculeata), which is a promising tropical palm tree, native to Brazil, whose fruits are rich in oil, proteins and dietary fiber. Hence, the objective of this work was to obtain and evaluate the physico-chemical and techno-functional properties of the macauba kernel protein isolate (MKPI). Defatted macauba kernel flour was obtained and used to produce the MKPI by isoelectric precipitation. Then, the proximate composition, amino acid profile, and physico-chemical and techno-functional properties of the MKPI were determined. The MKPI stood out for its high protein content (94.9%) and high levels of arginine (16.21%) and glutamate (20.84%). The MKPI average isoelectric point was at pH 4.9 and its proteins showed low solubility in the pH range from 4.0 to 6.0. Moreover, the hydrophobicity of MKPI proteins was higher at pH 3.5 than at pH 7.0, and they had higher oil holding capacity (153.77%) than water holding capacity (97.29%). Regarding the MKPI emulsifying and gelling properties, emulsions with 0.5% and 1.0% of MKPI remained stable during storage and the minimum gelling concentration was 14%. Thus, the MKPI has a great potential to be produced and used by the food industry due to its nutritional and techno-functional properties.
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Arecaceae , Aminoácidos/metabolismo , Arecaceae/química , Arginina/metabolismo , Fibras na Dieta/metabolismo , Glutamatos , Humanos , Proteínas de Plantas/metabolismo , Água/metabolismoRESUMO
In this study, the addition of monoolein to phosphatidylcholine (PC), tricaprylin, and propylene glycol (PG) mixtures was studied to produce fluid precursor formulations (FIPs) that could transform into hexagonal phase (resistant to aqueous dilution) in vitro and in vivo. The overall goal was to obtain FIPs that could incorporate chemopreventive drugs for subcutaneous administration in the mammary tissue to inhibit the development and/or recurrence of breast cancer. Increasing PG content reduced FIP viscosity up to ~ 2.5-fold, while increases in PC (over monoolein) increased the formation of emulsified systems. The hexagonal phase was observed at 20% of water and higher, with the minimum amount of water necessary for this formation increasing with PG content. The selected FIP formed a depot in vivo after ~ 24 h of administration; its structure was compatible with the hexagonal phase and it remained in the mammary tissue for at least 30 days, prolonging the permanence of a fluorescent probe. In vitro, the release of the synthetic retinoid fenretinide was slow, with ~ 9% of the drug released in 72 h. Consistent with this slow release, fenretinide IC50 in breast cancer cells was ~ 100-fold higher in the selected FIP compared to its solution. The FIP reduced cell migration and presented higher cytotoxicity towards tumor compared to non-tumor cells. Given the limited number of options for pharmacological prevention of breast cancer development and recurrences, this formulation could potentially find applicability to reduce the frequency of administration and improve local concentrations of chemopreventive drugs.
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Neoplasias da Mama , Fenretinida , Neoplasias da Mama/tratamento farmacológico , Liberação Controlada de Fármacos , Feminino , Corantes Fluorescentes , Humanos , Fosfatidilcolinas , Propilenoglicol/química , Água/químicaRESUMO
Two series of novel amphiphilic compounds were synthesized based on carbamates and ureas structures, using a modification of the synthesis methods reported by bibliography. The compounds were tested for organic solvent removal in a model wastewater. The lipophilic group of all compounds was a hexadecyl chain, while the hydrophilic substituent was changed with the same modifications in both series. The structures were confirmed by FT-IR, NMR, molecular dynamic simulation and HR-MS and their ability to gel organic solvents were compared. The SEM images showed the ureas had a greater ability to gel organic solvents than the carbamates and formed robust supramolecular networks, with surfaces of highly interwoven fibrillar spheres. The carbamates produced corrugated and smooth surfaces. The determination of the minimum gelation concentration demonstrated that a smaller quantity of the ureas (compared to the carbamates, measured as the weight percentage) was required to gel each solvent. This advantage of the ureas was attributed to their additional N-H bond, which is the only structural difference between the two types of compounds, and their structures were corroborated by molecular dynamic simulation. The formation of weak gels was demonstrated by rheological characterization, and they demonstrated to be good candidates for the removal organic solvents.
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Abstract The objective of the study was to evaluate the gelling properties of Dillenia indica mucilage in benzyl benzoate emulgel formulation. Mucilage was extracted from the fruits of Dillenia indica using established methods and characterized by rheology and swelling. Emulsion (F1) was prepared using the continental emulsification method. Gelling agents (2 %w /v) were prepared by dispersing in distilled water with constant stirring at a moderate speed using a magnetic stirrer. F1 was added to the gel (0-75 %w /w) to obtain emulgel formulations and evaluated using viscosity, globule size, pH, release profiles and kinetic modeling. Data were expressed as mean ± SD, and similarity factor (f2) was used to compare all formulations. Formulation viscosity was significantly higher with carbopol than with Dillenia; globule sizes increased with concentration of gelling agents, and pH reduced as the concentration of Dillenia increased. All formulations showed controlled release properties with t80 ranging between 114 and 660 min. The release was governed by Korsmeyer-Peppas model. Formulation F5 prepared with 50 % Dillenia showed highest similarity to F4 prepared with 75 %w /w carbopol. Dillenia indica demonstrated acceptable gelling properties comparable with that of carbopol and could be improved for use in emulgel formulations.
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Benzoatos/administração & dosagem , Dilleniaceae/anatomia & histologia , Geleificantes , Mucilagem Vegetal/agonistas , Emulsões/análise , MétodosRESUMO
Aristotelia chilensis is a plant rich in phenolics and other bioactive compounds. Their leaves are discarded as waste in the maqui berry industry. A new application of these wastes is intended by the recovery of bioactive compounds using pressurized hot water extraction with conventional or microwave heating. Both technologies have been selected for their green character regarding the type of solvent and the high efficiency in shorter operation times. Extractions were performed in the temperature range 140-200 °C with a solid/liquid ratio of 1:15 (w:w). The extracts' total phenolic content, antioxidant capacity, and saccharides content obtained with both heating methods were measured. Additionally, the thermo-rheological properties of the gelling matrix enriched with these extracts were analyzed. Optimum conditions for lyophilized extracts were found with conventional heating, at 140 °C and 20 min extraction; 250.0 mg GAE/g dry extract and 1321.5 mg Trolox/g dry extract. Close to optimum performance was achieved with microwave heating in a fraction of the time (5 min) at 160 °C (extraction), yielding extracts with 231.9 mg GAE/g dry extract of total phenolics and antiradical capacity equivalent to 1176.3 mg Trolox/g dry extract. Slightly higher antioxidant values were identified for spray-dried extracts (between 5% for phenolic content and 2.5% for antioxidant capacity). The extracts obtained with both heating methods at 200 °C contained more than 20% oligosaccharides, primarily glucose. All the formulated gelling matrices enriched with the obtained extracts displayed intermediate gel strength properties. The tested technologies efficiently recovered highly active antioxidant extracts, rich in polyphenolics, and valuable for formulating gelling matrices with potential applicability in foods and other products.
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Elaeocarpaceae/química , Glucose/isolamento & purificação , Hidrogéis/química , Oligossacarídeos/isolamento & purificação , Glucose/química , Oligossacarídeos/química , Pressão , Temperatura , Água/químicaRESUMO
Cooked crab meat subjected to a cutting process can aggregate again, forming weak gels. The objective of this work was to determine the effect of two mixing methods, combined with the addition of the microbial enzyme TGase (MTGase) on the mechanical and functional properties of gels from washed or unwashed blue crab (Callinectes sapidus) meat. Live crabs were obtained from Laguna Madre, Tamaulipas, Mexico, and cooked at 120°C for 20 min before hand-picking the meat from the shell. Cooked meat was processed by mixing and cut at temperatures of 25 or 60°C, without (control) or 0.5% of MTGase. Then cooked at 90°C for 15 min. Changes in texture profile analysis, percentage of extractable water, and color were evaluated. The mixing method at 60°C allowed increasing the textural properties of the gels, and the addition of MTGase significantly improved the mechanical properties. The results allowed stablishing a viable technique to obtain restructured gels from cooked crab meat with no need to extract the soluble compounds responsible for their distinctive odor and taste which often affect the mechanical properties.
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Acanthamoeba spp. are the causative agents of a sight-threatening infection of the cornea known as Acanthamoeba keratitis (AK). Amphotericin B - deoxycholate (AB) is used in the treatment of infectious keratitis, however, its topical administration has side effects as blepharitis, iritis, and painful instillation. In this context, the preheating of AB can decrease its toxicity by the formation of super aggregates (hAB). hAB associated with a thermoreversible in situ gelling ophthalmic system is a promising option due to the latter biocompatibility, low toxicity, and high residence time on the ocular surface. Our objective was to develop a topical ocular formulation of hAB for the treatment of AK. After heating at 70°C for 20 min, hAB was incorporated into a thermoreversible gelling system. The amebicidal activity of AB and hAB was evaluated against trophozoites and cysts of A. castellanii (ATCC 50492) and a regional clinical isolate (IC01). The results showed that the preheating of AB did not change the pharmacological action of the drug, with the amebicidal effect of AB and hAB under trophozoites and cysts of Acanthamoeba spp. The thermoreversible system remained stable, allowing the increase of drug retention time. For assessment of cytotoxicity, HUVEC (ATCC® CRL-1730) cells were challenged with AB and hAB for 48h. Cell viability was assessed, and hAB did not show cytotoxicity for HUVEC cells. As far as we know this was the first study that showed the preheated AB associated with a thermoreversible in situ gelling ophthalmic system as a promising system for topical ocular topical administration of hAB for AK therapy.
Assuntos
Ceratite por Acanthamoeba , Acanthamoeba , Amebicidas , Ceratite por Acanthamoeba/tratamento farmacológico , Amebicidas/farmacologia , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Animais , TrofozoítosRESUMO
The need of pharmacological strategies to preclude breast cancer development motivated us to develop a non-aqueous microemulsion (ME) capable of forming a depot after administration in the mammary tissue and uptake of interstitial fluids for prolonged release of the retinoid fenretinide. The selected ME was composed of phosphatidylcholine/tricaprylin/propylene glycol (45:5:50, w/w/w) and presented a droplet diameter of 175.3 ± 8.9 nm. Upon water uptake, the ME transformed successively into a lamellar phase, gel, and a lamellar phase-containing emulsion in vitro as the water content increased and released 30% of fenretinide in vitro after 9 days. Consistent with the slow release, the ME formed a depot in cell cultures and increased fenretinide IC50 values by 68.3- and 13.2-fold in MCF-7 and T-47D cells compared to a solution, respectively. At non-cytotoxic concentrations, the ME reduced T-47D cell migration by 75.9% and spheroid growth, resulting in â¼30% smaller structures. The depot formed in vivo prolonged a fluorochrome release for 30 days without producing any sings of local irritation. In a preclinical model of chemically induced carcinogenesis, ME administration every 3 weeks for 3 months significantly reduced (4.7-fold) the incidence of breast tumors and increased type II collagen expression, which might contribute to limit spreading. These promising results support the potential ME applicability as a preventive therapy of breast cancer.
Assuntos
Anticarcinógenos/administração & dosagem , Neoplasias da Mama/prevenção & controle , Fenretinida/administração & dosagem , Neoplasias Mamárias Experimentais/prevenção & controle , Animais , Anticarcinógenos/farmacocinética , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Emulsões , Feminino , Fenretinida/farmacocinética , Humanos , Concentração Inibidora 50 , Células MCF-7 , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , Metilnitrosoureia/administração & dosagem , Metilnitrosoureia/toxicidade , Camundongos , RatosRESUMO
The purpose of the food industry is to ensure the availability of safe and nutritious food ingredients for human consumption. Sweet potato is a crop with excellent industrialization possibilities for human food due to its important nutrient content. The objective of this study was to evaluate the effect of an alginate-calcium sulfate-tripolyphosphate (PPTS) gelling system on the physicochemical and sensory characteristics of restructured sweet potato products. Fifteen formulations with varied concentrations of alginate, calcium sulfate, and PPTS were elaborated and subjected to a ordered-preference test. The physicochemical composition and color parameters of the preferred samples were determined, and the consumer acceptance, intention to purchase, and acceptability index (AI) were assessed. The preferred formulations (p ≤ 0.05) were F1, F6, F10, F11, and F14, and the gel formation was efficient at retaining water and preventing the restructured products from absorbing fat during frying. The restructured products with the highest water retention and lowest fat absorption were F11 (46.75%), F10 (44.53%), and F14 (43.29%). In the acceptance test, no differences (p ≥ 0.05) were found in the attributes softness, crunchiness, and sweet potato flavor. Formulations F6 and F14 obtained the highest acceptability index (AI), equal to or higher than 70%, indicating that they could represent viable alternatives for the industrial transformation of sweet potato for its possible commercialization.
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Ca(II)-alginate beads are being produced for a broad spectrum of biotechnological uses. Despite the simplicity of their manufacturing process, in these highly complex arrangements, the final properties of the material strongly depend on the supramolecular scaffolding. Here we present a cost-effective automatized Optical Video Microscopy approach for in situ evaluation of the kinetics of alginate bead formation. With simple mathematic modeling of the acquired data, we obtained key parameters that reveal valuable information on the system: the time course of gel-front migration correlates with the plateau of the storage module, and total volume shrinkage is highly related to the stabilization of shear strain and shear stress at the yield point. Our results provide feasible and reproducible tools, which allow for a better interpretation of bead formation kinetics and a rapid screening technique to use while designing gelling materials with specific properties for technological applications.
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The aimof this study was to establish a low-cost alternative protocol for micropropagation ofSolanum lycopersicumL. var.cerasiforme,popularly known as cherry tomato. In the in vitroestablishment, culture mediacontaining Laboratory Reagent-grade (LR)and commercialsucrose and varied concentrations of corn starch and agarwere tested. The replacement of thermal sterilization, usingautoclave,withchemicalsterilization,adding sodium hypochlorite (2%) in the medium, was also evaluated. In the multiplication stage,the mediumwas supplemented with agar and/or corn starch and commercial sucrose.Forrooting, agrowth regulator-free medium withcommercialsucrose supplemented with agar and/or starch was used. Themicroplants were thentransplanted into plasticcontainerscontainingonlygarden substrateandsubsequentlyacclimatized in a greenhouse.The results make it possibleto conclude that the reduction of costs in the micropropagation of cherry tomatocan beobtained by replacing LRsucrose with commercial sucrose,and by the use of chemical sterilization of the culture medium withsodium hypochlorite. The replacement of agar withcorn starch can be done partially, in the stages of establishment and multiplication,and totally, during rooting.
O objetivo deste estudo foi estabelecer um protocolo alternativo de baixo custo para micropropagação de Solanum lycopersicumL. var. cerasiforme, conhecida popularmente como tomate cereja. Noestabelecimento in vitro foram testados meios de cultura contendo sacarose P.A. e comercial e concentrações variadas de amido de milho e ágar. Também avaliou-se a substituição da esterilização física pela esterilização química. Na etapa de multiplicação o meio foi suplementado com ágar e/ou amido de milho e sacarose comercial. Para o enraizamento utilizou-se meio isento de regulador com sacarose comercial suplementado com ágar e/ou amido. As microplantas foramtransplantadas para terra vegetal e aclimatizadas em casa de vegetação. Os resultados permitem concluir que a redução de custos na micropropagação do tomate cereja é obtida pela substituição de sacarose P.A. pela sacarose comercial, substituição parcial (estabelecimento e multiplicação) e total (enraizamento) de ágar por amido de milho e pela utilização de esterilização química do meio.
Assuntos
Esterilização , Geleificantes , Solanum lycopersicum/crescimento & desenvolvimento , Redução de CustosRESUMO
The aimof this study was to establish a low-cost alternative protocol for micropropagation ofSolanum lycopersicumL. var.cerasiforme,popularly known as cherry tomato. In the in vitroestablishment, culture mediacontaining Laboratory Reagent-grade (LR)and commercialsucrose and varied concentrations of corn starch and agarwere tested. The replacement of thermal sterilization, usingautoclave,withchemicalsterilization,adding sodium hypochlorite (2%) in the medium, was also evaluated. In the multiplication stage,the mediumwas supplemented with agar and/or corn starch and commercial sucrose.Forrooting, agrowth regulator-free medium withcommercialsucrose supplemented with agar and/or starch was used. Themicroplants were thentransplanted into plasticcontainerscontainingonlygarden substrateandsubsequentlyacclimatized in a greenhouse.The results make it possibleto conclude that the reduction of costs in the micropropagation of cherry tomatocan beobtained by replacing LRsucrose with commercial sucrose,and by the use of chemical sterilization of the culture medium withsodium hypochlorite. The replacement of agar withcorn starch can be done partially, in the stages of establishment and multiplication,and totally, during rooting.(AU)
O objetivo deste estudo foi estabelecer um protocolo alternativo de baixo custo para micropropagação de Solanum lycopersicumL. var. cerasiforme, conhecida popularmente como tomate cereja. Noestabelecimento in vitro foram testados meios de cultura contendo sacarose P.A. e comercial e concentrações variadas de amido de milho e ágar. Também avaliou-se a substituição da esterilização física pela esterilização química. Na etapa de multiplicação o meio foi suplementado com ágar e/ou amido de milho e sacarose comercial. Para o enraizamento utilizou-se meio isento de regulador com sacarose comercial suplementado com ágar e/ou amido. As microplantas foramtransplantadas para terra vegetal e aclimatizadas em casa de vegetação. Os resultados permitem concluir que a redução de custos na micropropagação do tomate cereja é obtida pela substituição de sacarose P.A. pela sacarose comercial, substituição parcial (estabelecimento e multiplicação) e total (enraizamento) de ágar por amido de milho e pela utilização de esterilização química do meio.(AU)
Assuntos
Solanum lycopersicum/crescimento & desenvolvimento , Redução de Custos , Esterilização , GeleificantesRESUMO
Agarose and κ-carrageenan were oxidized using (2,2,6,6-tetramethylpiperidinyl)oxy (TEMPO) in the presence of NaOCl and NaBr. Products with several degrees of oxidation were structurally characterized. The mechanical spectra were determined: derivatives with a medium to high degree of oxidation give rise to polysaccharides that behave like dilute solutions in water, whereas those with a degree of oxidation close to 20 % keep the gelling properties with a different thermo-rheological response towards pH (6.5 or 4.0) and counterions (K+ or Ca2+) in comparison with the native polysaccharides. For instance, they showed a marked dependence on the presence of calcium ions, observed in the increase of thermal stability and dynamic elastic component (G') value, due to the known interaction of this divalent cation with the carboxylate groups. In this sense, these derivatives with low oxidation degrees have proven to be not only thermosensitive, like the native polysaccharide, but also pH- and calcium-sensitive.
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Carragenina/química , Géis/química , Reologia , Sefarose/química , Óxidos N-Cíclicos/química , Concentração de Íons de Hidrogênio , Íons/química , Oxirredução , Rodófitas/metabolismo , Alga Marinha/metabolismo , ViscosidadeRESUMO
The aim of the present work was the development of an innovative in situ gelling system, to be applied on the mucosa of the distal colon via rectal route. The system consisted of three polymers having different functions: gellan (GG), able to jellify in presence of ions; methylcellulose (MC), a thermosensitive polymer with a gelation temperature close to 50 °C; and hydroxypropylcellulose (HPC), a mucoadhesive polymer. The three polymers were able to act synergistically, increasing the permanence of the vehicle on the mucosa and forming a protective gel layer. A DoE approach, "simplex centroid mixture design," was used to identify the optimal quantitative composition of the vehicle. The response variables considered were: vehicle viscosity at room temperature; increase in vehicle viscosity on increasing temperature (from room to physiological value) and upon dilution with simulated colonic fluid (SCF); and viscoelastic behavior, thixotropic area, and mucoadhesion properties of the gel formed at 37 °C upon dilution in SCF. The optimized vehicle was loaded with maqui berry extract (MBE), known for its antioxidant and anti-inflammatory properties. MBE loading (0.5% w/w) into the vehicle improved rheological and mucoadhesive properties of the formulation. Both MBE and the optimized vehicle were not cytotoxic towards human fibroblasts and Caco-2 cells. Moreover, the optimized vehicle did not affect MBE antioxidant properties.
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Carrot residues were upgraded as pectin-enriched fractions (PEFs) useful for functional food formulation due to co-extracted antioxidants (α- and ß-carotenes, lutein, α-tocopherol), and gelling effect. High power ultrasound (US)-enzyme assisted extraction was applied for efficiency and sustainability. Carrot powder (CP) in citrate-buffer (pH 5.20) was submitted to US-pretreatment (12.27â¯W/cm2: 20â¯kHz, 80% amplitude, 20â¯min) and a subsequent digestion (5â¯h-40⯰C) without or with hemicellulase or cellulase. US-hemicellulase led to the highest PEF yield (27.1%), and extracted almost the whole pectin content of CP. US-pretreatment increased the extraction yield of all PEFs, but the existence of an additional positive effect of the following step depended on the enzyme used. PEFs contained 40-47% of UA with low DM (24-49.9%), and co-extracted antioxidants. US decreased the antioxidant contents, DM, and molecular weight, but allowed obtaining calcium crosslinked true gels, also with higher elastic modulus than non-US-extracted PEFs, being promising as food additives.
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Antioxidantes/isolamento & purificação , Daucus carota/química , Pectinas/isolamento & purificação , Carotenoides/isolamento & purificação , Celulase/metabolismo , Manipulação de Alimentos/métodos , Luteína/isolamento & purificação , Raízes de Plantas/química , Ultrassom , alfa-Tocoferol/isolamento & purificaçãoRESUMO
Ocular allergy is one of the most common disorders of the eye surface. Following diagnosis this condition is typically treated with preparations containing antihistamines. However, anatomy of the eye and its natural protective mechanisms create challenges for ocular drug delivery. Rapid elimination of antihistamine substances due to short residency times following application can lead to insufficient treatment of ocular allergies. With this in mind, the aim of this study was to prepare a controlled ocular delivery system to extend the retention time of olopatadine hydrochloride (OLO) and in doing so to reduce the need for frequent application. We developed extended-release ocular in situ gelling systems for which in vivo retention times were determined in sheep following in vitro characterization and cytotoxicity studies. In vivo results were then compared to commercially available Patanol eye drops. the transparent gels formulated using appropriate amounts of polymers and having longer ocular retention times appear to be a viable alternative to commercially available eye drops.