RESUMEN
Abstract Passiflora nitida Kunth, an Amazonian Passiflora species, is little studied, although the specie's high biological potential. Herein the plant's pharmacognostic characterization, extract production, antioxidant potential evaluation, and application of this extract in cosmetic products is reported. The physical chemical parameters analyzed were particle size by sieve analysis, loss through drying, extractive yield, total ash content, laser granulometry, specific surface area and pore diameter (SBET), differential scanning calorimetry, thermogravimetry (TG), and wave dispersive X-Ray fluorescence (WDXRF). Total phenol/flavonoid content, LC-MS/MS analysis, DPPH and ABTS antioxidant radical assays, cytotoxicity, melanin, and tyrosinase inhibition in melanocytes test provided evidence to determine the content of the major constituent. P. nitida dry extract provided a fine powder with mesopores determined by SBET, with the TG curve showing five stages of mass loss. The antioxidant potential ranged between 23.5-31.5 mgâmL-1 and tyrosinase inhibition between 400-654 µgâmL-1. The species presented an antimelanogenic effect and an inhibitory activity of cellular tyrosinase (26.6%) at 25 µg/mL. The LC-MS/MS analysis of the spray-dried extract displayed the main and minor phenolic compounds constituting this sample. The results indicate that P. nitida extract has promising features for the development of cosmetic formulations
Asunto(s)
Extractos Vegetales/análisis , Hojas de la Planta/efectos adversos , Cosméticos/clasificación , Passiflora/clasificación , Termogravimetría/métodos , Rayos X/efectos adversos , Rastreo Diferencial de Calorimetría/métodos , Monofenol Monooxigenasa/antagonistas & inhibidores , Compuestos Fenólicos , Melaninas , Antioxidantes/efectos adversosRESUMEN
Arabinoxylan (AX) and cellulose were extracted from wheat straw, whereas starch was extracted from potato peel. Thereafter, cellulose and starch were esterified with lauric, myristic, palmitic and stearic acids to prepare corresponding cellulose (CFAs) and starch fatty acid esters (SFAs) with DS 2.1-2.8. XRD study revealed remarkable loss of crystallinity in cellulose and starch due to fatty acid esterification. The addition of palmitate and stearate esters of cellulose and starch to AX formed laminar film microstructures which limited water vapor permeability whereas films prepared by blending AX with laurate and myristate esters of starch and cellulose were less effective as water vapor barrier due to their non-layer microstructures. The laminar structures also resulted significant reduction in mechanical strength of the composite films. Furthermore, all AX-CFAs and AX-SFAs films were thermally more stable than native composite films. These films might be used to produce industrially useful coating material for food products.
Asunto(s)
Celulosa/química , Ácidos Grasos/química , Almidón/química , Xilanos/química , Esterificación , Ésteres/química , Embalaje de Alimentos/métodos , Humanos , Fenómenos Mecánicos , Microscopía Electrónica de Rastreo/métodos , Permeabilidad , Fenómenos Físicos , Solanum tuberosum/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Vapor , Ácidos Esteáricos/química , Termogravimetría/métodos , Triticum/química , Agua/químicaRESUMEN
High amylose maize starch (HAMS) and waxy maize starch (WMS) were modified by propionylation and their corresponding physicochemical characteristics, digestion and fermentation properties were studied. The results indicated that two new peaks related to methylene (2.20 ppm) and methyl (0.97 ppm) in the NMR spectrum were formed, indicating the occurrence of propionylation, and this was further confirmed by the formation of a characteristic absorption at 1747 cm-1 in the FTIR spectrum. The propionylation led the modified starch having a lower electron density contrast between the crystalline and amorphous flakes, resulting in the formation of a more compact structure following the increased degrees of substitution (DS). The propionylated starch also had a higher thermal stability and hydrophobicity. These structural changes increased the content of resistant starch (RS) and reduced the predicted glycemic index. More importantly, the gut microbiota fermentation properties indicated that the propionylation of the starch can not only increase the yield of propionate, but also increase the concentration of total short-chain fatty acids (SCFAs). This study highlights a new approach to significantly enhance the RS content in starch, together with an increased SCFA generation capacity.
Asunto(s)
Digestión , Fermentación , Almidón/química , Zea mays/química , Amilosa/química , Ácidos Grasos Volátiles/análisis , Heces/química , Femenino , Microbioma Gastrointestinal , Índice Glucémico , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Espectroscopía de Resonancia Magnética/métodos , Masculino , Propionatos/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Almidón/metabolismo , Termogravimetría/métodos , Zea mays/metabolismoRESUMEN
Thermal analyses were used to determine thermal properties and transitions in model dough and gluten network induced by five oil pomaces obtained from seeds of black seed, pumpkin, hemp, milk thistle and primrose. The model dough was supplemented with 3%, 6% and 9% of the pomaces. Analysis of TGA parameters of supplemented model dough and gluten showed that both objects were thermally stable. However, analysis of difference TGA thermograms indicated that samples supplemented with pomaces differ in thermal behaviour. The differences were confirmed by DSC results. In the case of model dough, supplementation caused appearance of two endothermic peaks at ca. 295 and 340 °C and significant increase in transition enthalpy. Modified gluten thermograms showed one exothermic peak at 280 °C which enthalpy changed slightly with increase in pomace content. The present results indicated that model dough is characterized by more ordered structure comparing to control and gluten samples.
Asunto(s)
Pan , Rastreo Diferencial de Calorimetría/métodos , Glútenes/química , Aceites de Plantas/química , Termogravimetría/métodos , Harina , Calefacción , Semillas/química , TermodinámicaRESUMEN
This study focuses on the production and characterization of electrosprayed cashew gum (CG) microparticles that encapsulate ß-carotene. CG is an inexpensive, non-toxic polysaccharide obtained from Anacardium occidentale trees. Encapsulation of ß-carotene in CG was performed by electrospraying from two emulsion formulations (water : oil ratios 80:20 and 90:10 (v/v)) in which the dispersed phase consisted of ß-carotene dissolved in castor oil, and the continuous phase was a CG aqueous solution. Spherical particles with smooth surface and medium size between 3 and 6 µm were obtained. The particles produced from the 90:10 (v/v) emulsion showed a loading capacity of 0.075 ± 0.006 % and a minor amount of extractable ß-carotene, 10.75 ± 2.42 %. ATR-FTIR confirmed the absence of interaction between the particles' components. CG demonstrated to offer thermoprotection, and photoprotection for short periods of time. These results make CG a viable candidate to encapsulate bioactive compounds via electrospraying for agricultural, food and pharmaceutical applications.
Asunto(s)
Anacardium/química , Gomas de Plantas/química , Polisacáridos/química , beta Caroteno/química , Agricultura/métodos , Aceite de Ricino/química , Composición de Medicamentos/métodos , Emulsiones/química , Industria de Alimentos/métodos , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Termogravimetría/métodos , Agua/químicaRESUMEN
Nanocellulose crystals (NCCs) were successfully prepared via acid hydrolysis from an abundant agricultural waste (tea stalk) in China. The effective factors for NCC yield were modeled by the response surface methodology (RSM). The RSM determined the reaction conditions (H2SO4 concentration, hydrolysis temperature, and reaction time) that optimized the yield of tea stalk NCCs (TNCCs). Under the optimized operating conditions, the fundamental properties of TNCCs were characterized via transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), laser diffraction particle-size analyzer, and scanning probe microscopy (SPM). Wood NCCs (WNCCs) and microcrystalline NCCs (MNCCs) were simultaneously prepared from common wood and microcrystalline cellulose under the same conditions. The results show that TNCCs not only shows similar physical and chemical properties with WNCCs and MNCCs, but also has better stability. Therefore, this study offers novel routes for high-valued utilization of tea stalk and provides some theoretical guidance for utilizing cellulose obtained from tea stalk.
Asunto(s)
Celulosa/química , Cristales Líquidos/química , Nanopartículas/química , Té/química , Residuos , Celulosa/aislamiento & purificación , Fraccionamiento Químico , Concentración de Iones de Hidrógeno , Hidrólisis , Nanopartículas/ultraestructura , Fitoquímicos/química , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Termogravimetría/métodos , Difracción de Rayos XRESUMEN
Lignin-Al2O3 hybrids were tested as effective additives for application in abrasive materials. The main focus was on the reduction of environmental pollution. The emission of volatile compounds, mainly phenol and formaldehyde, was investigated using detailed evolved gas analysis (EGA) performed by means of mass spectroscopy (QMS) in combined differential scanning calorimetry (DSC) and thermogravimetry (TG) analysis. It was established that the addition of lignin-Al2O3 hybrid additives can reduce the emission of phenol and formaldehyde. Crucially, free phenol emission was not detected from the lignin-Al2O3 additives or from lignin itself using the TG-MS method. Moreover, the addition of lignin-type fillers to phenolic composites can lower emissions of the two aforementioned compounds. No emission of other toxic compounds was detected. The mechanical properties of the lignin-alumina hybrids and resin systems were investigated using the three-point flexural test (also as an element of an ageing test), a compressive test, and testing of abrasibility. The results indicate that the lignin and alumina used as a hybrid additive for abrasive materials improve the adhesion between the binder and abrasive grain, and increase the flexibility of the composites, which has a positive impact on the performance of the final products.
Asunto(s)
Óxido de Aluminio/química , Lignina/química , Rastreo Diferencial de Calorimetría/métodos , Formaldehído/química , Espectrometría de Masas/métodos , Fenol/química , Termogravimetría/métodosRESUMEN
In this study, a novel ionic liquid-type surfactant modified attapulgite named as 1-dodecyl-3-methylimidazolium bromide-attapulgite (C12MIM-ATP) is successfully prepared and applied in dispersive solid phase extraction (dSPE) for the fast determination of pyrethroid residues in tea drinks. The primary factors that influenced the extraction efficiency, including sorbent type, amount of sorbent, extraction time, desorption conditions, pH and ionic strength, are investigated. The optimized results reveal that the extraction and desorption equilibria are rapidly obtained within 1â¯min. Under the optimized conditions, good linearity (2-500⯵g/L) is observed for four pyrethroids in tea drinks with determination coefficients (r2) ranged from 0.9992 to 1.0000. The limits of detection (LODs) are 0.6⯵g/L for all pesticides. Acceptable extraction recoveries of target analytes are found from 90.28 to 107.56% with relative standard deviations (RSDs) less than 8.30% in real tea drink samples. The batch-to-bath repeatability is evaluated by recovery test on five independent synthesized C12MIM-ATP sorbents. Satisfactory batch-to-batch repeatability is obtained with the recovery factors varied in 15%. A small matrix effect is observed using C12MIM-ATP as the sorbent for detection pyrethroids in tea drinks.
Asunto(s)
Compuestos de Magnesio/síntesis química , Piretrinas/análisis , Piretrinas/química , Compuestos de Silicona/síntesis química , Extracción en Fase Sólida/métodos , Tensoactivos/química , Té/química , Cromatografía Líquida de Alta Presión/métodos , Líquidos Iónicos/química , Límite de Detección , Microscopía Electrónica de Rastreo/métodos , Plaguicidas/análisis , Plaguicidas/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Propiedades de Superficie , Termogravimetría/métodosRESUMEN
A controlled release fertilizer system based on phosphate bound-carboxymethyl starch-graft-polyacrylamide (P-CMS-g-PAM) has been prepared in order to deliver the phosphate fertilizer to the plant at a constant rate thereby. This system aims to increase fertilizer phosphorus use efficiency (FPUE) and maintain a hydration level for the plant at the same time. Two types of starch phosphate monoesters were prepared using mono-ammonium (MAP) and di-ammonium phosphate (DAP). First, starch was converted to carboxymethyl starch and then was phosphorylated with mono-ammonium dihydrogen phosphate and di-ammonium dihydrogen phosphate. After phosphorylation, the samples were grafted with acrylamide in the presence of methylene bisacrylamide as a crosslinking agent. The prepared systems of P-CMS-g-PAM were differently characterized by Fourier transformer infrared (FT-IR), thermogravimetric analysis (TGA), scanning electron microscope (SEM) and phosphorous analysis. The swelling behavior was investigated. The kinetics of grafting reaction were also studied. The release behavior of phosphate bound was studied at pHâ¯7 and 25⯰C. The mechanism of the phosphate release from P-CMS-g-PAM was examined using the Korsmeyer-Peppas model.
Asunto(s)
Resinas Acrílicas/química , Preparaciones de Acción Retardada/química , Fósforo/química , Almidón/análogos & derivados , Fertilizantes , Microscopía Electrónica de Rastreo/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Almidón/química , Temperatura , Termogravimetría/métodosRESUMEN
Pyrolysis is an eco-friendly process to achieve valuable products like bio-oil, char and gases. In the last decades, biochar production from pyrolysis of a wide variety of industrial and agricultural wastes become popular, which can be utilized as adsorbent instead of the expensive activated carbons. In this study, cherry pulp was pyrolyzed in a fixed bed tubular reactor at five different temperatures (400, 500,550, 600 and 700 °C) and three different heating rates (10, 100 and 200 °C/min) to obtain biochar. Proximate, ultimate, nitrogen adsorption/desorption isotherms, scanning electron microscopy, thermogravimetric analysis, x-ray fluorescence, x-ray diffraction, and Fourier transform infrared spectroscopy were performed on cherry pulp and its chars to examine the chemical alterations after the pyrolysis process. Biochar yields were decreased with increasing pyrolysis temperature and heating rate, based on experimental results. Porous biochars are carbon rich and includes high potassium content. The aromaticity of biochars increased and O/C mass ratio reduced with an increase in the pyrolysis temperature as a result of the development of compact aromatic structure in char. Pyrolysis provides a promising conversion procedure for the production of high energy density char which has promising applications in existing coal-fired boilers without any upgrading.
Asunto(s)
Carbón Orgánico , Aceites de Plantas/química , Polifenoles/química , Termogravimetría/métodos , Adsorción , Animales , Carbono/química , Gases , Calefacción , Calor , Microscopía Electrónica de Rastreo , Nitrógeno/química , Aceites de Plantas/análisis , Polifenoles/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Difracción de Rayos XRESUMEN
In this study, pyrolysis of plum stone was investigated by thermogravimetric analysis in a nitrogen atmosphere at heating rates of 5, 10, 20 and 40 °C min(-1). Pyrolysis characteristics and the thermal-decomposition rate were significantly affected by variation in the heating rate. However, the heating rate slightly affected the total yield of the volatile matters. Activation energy of the pyrolysis reaction was evaluated by model-free methods, Friedman and Kissingere-Akahirae-Sunose. Results of the Master-Plots method indicated that the most probable reaction model function was the nth order reaction model function as f(x) = (1-x) (3.11), A = 8.02x10(12) under a mean activation energy of 150.61 kJ mol(-1). Proximate and ultimate analysis showed that plum stone can be considered as a favourable source for energy production owing to its low moisture and ash content, and high volatile matter ratio and moderate heating value.
Asunto(s)
Frutas/química , Calor , Incineración , Residuos Industriales/análisis , Prunus domestica/química , Termogravimetría/métodos , Agricultura , Modelos TeóricosRESUMEN
Five different biomass samples were selected for this study, including miscanthus, distillers dried grain (DDG), wheat shorts, wheat straw and UK wood. These samples were thermochemically treated to alter the lignin, cellulose and hemicellulose composition. Thermogravimetric tests were carried out on these samples to determine thermal behaviours of biomass and its individual lignocellulosic components. The relationship between thermal behaviour of biomass and its corresponding lignocellulosic composition was revealed. The reliability of this relationship was proved by thermogravimetric analysis of samples of artificial biomass prepared by mixing commercially obtained lignin, cellulose and hemicellulose at various blending ratios. It is shown that actual biomass profiles can be predicted with some degree of accuracy based on the lignocellulosic composition.
Asunto(s)
Calor , Lignina/análisis , Lignina/química , Modelos Químicos , Extractos Vegetales/química , Termogravimetría/métodos , Biomasa , Simulación por Computador , Extractos Vegetales/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , TermodinámicaRESUMEN
In this study, the optimal conditions for biomass torrefaction were determined by comparing the gain of energy content to the weight loss of biomass from the final products. Torrefaction experiments were performed at temperatures ranging from 220 to 280°C using 20-80min reaction times. Polynomial regression models ranging from the 1st to the 3rd order were used to determine a relationship between the severity factor (SF) and calorific value or weight loss. The intersection of two regression models for calorific value and weight loss was determined and assumed to be the optimized SF. The optimized SFs on each biomass ranged from 6.056 to 6.372. Optimized torrefaction conditions were determined at various reaction times of 15, 30, and 60min. The average optimized temperature was 248.55°C in the studied biomass when torrefaction was performed for 60min.
Asunto(s)
Técnicas Químicas Combinatorias/métodos , Calor , Modelos Estadísticos , Extractos Vegetales/química , Termogravimetría/métodos , Árboles/química , Madera/química , Algoritmos , Simulación por Computador , Análisis de RegresiónRESUMEN
There is an interest in the development of an antioxidant packaging fully biodegradable to increase the shelf life of food products. An active film from cassava starch bio-based, incorporated with aqueous green tea extract and oil palm colorant was developed packaging. The effects of additives on the film properties were determined by measuring mechanical, barrier and thermal properties using a response surface methodology design experiment. The bio-based films were used to pack butter (maintained for 45 days) under accelerated oxidation conditions. The antioxidant action of the active films was evaluated by analyzing the peroxide index, total carotenoids, and total polyphenol. The same analysis also evaluated unpacked butter, packed in films without additives and butter packed in LDPE films, as controls. The results suggested that incorporation of the antioxidants extracts tensile strength and water vapor barrier properties (15 times lower) compared to control without additives. A lower peroxide index (231.57%), which was significantly different from that of the control (p<0.05), was detected in products packed in film formulations containing average concentration of green tea extracts and high concentration of colorant. However, it was found that the high content of polyphenols in green tea extract can be acted as a pro-oxidant agent, which suggests that the use of high concentration should be avoided as additives for films. These results support the applicability of a green tea extract and oil palm carotenoics colorant in starch films totally biodegradable and the use of these materials in active packaging of the fatty products.
Asunto(s)
Antioxidantes/química , Manihot/química , Extractos Vegetales/química , Aceites de Plantas/química , Almidón/química , Té/química , Antioxidantes/farmacología , Mantequilla , Carotenoides/análisis , Flavonoides/análisis , Embalaje de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Membranas Artificiales , Oxidación-Reducción/efectos de los fármacos , Aceite de Palma , Permeabilidad , Peróxidos/análisis , Extractos Vegetales/farmacología , Polifenoles/análisis , Reproducibilidad de los Resultados , Vapor , Propiedades de Superficie , Termogravimetría/métodos , Factores de TiempoRESUMEN
Anthraquinone and its derivatives could serve as photo-sensitizers and generate radicals and reactive oxygen species in polymers under exposure of UVA or day light. Such a property was utilized in development of novel light-induced surface radical graft polymerizations on cotton fibers that were dyed with an anthraquinone derivative, 2-ethylanthraquinone. Several functional monomers were directly grafted onto the dyed cotton fibers upon UVA exposure. The chemical and morphological structures and thermal properties of the grafted fibers were confirmed and characterized by Fourier transform infrared spectrometer (FTIR), scanning electron microscope (SEM) and thermal gravimetric analysis (TGA). Reaction conditions including concentrations of the photosensitizer, the amount of monomers, as well as UVA irradiation time could influence grafting efficiencies. More interestingly, the surface graft polymerization did not significantly change the light active functions of the agent, evidenced by the light-active antimicrobial functions of the grafted fibers.
Asunto(s)
Antraquinonas/química , Antibacterianos/farmacología , Fibra de Algodón , Acrilatos/química , Antibacterianos/química , Celulosa/química , Evaluación Preclínica de Medicamentos/métodos , Escherichia coli K12/efectos de los fármacos , Luz , Microscopía Electrónica de Rastreo , Fármacos Fotosensibilizantes/química , Polimerizacion , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Termogravimetría/métodos , Rayos UltravioletaRESUMEN
Pyrolysis of Milkweed was carried out in a thermogravimetric analyzer and a bubbling fluidized bed reactor. Total liquid yield of Milkweed pyrolysis was between 40.74% and 44.19 wt% between 425 °C and 550 °C. The gas yield increased from 27.90 wt% to 33.33 wt% with increasing reaction temperature. The higher heating values (HHV) of the Milkweed bio-oil were relatively high (30.33-32.87 MJ/kg) and varied with reaction temperature, feeding rate and fluidization velocity. The selectivity for CO2 was highest within non-condensable gases, and the molar ratio of CO2/CO was about 3 at the different reaction conditions. The (13)C NMR analysis, of the bio-oil showed that the relative concentration carboxylic group and its derivatives was higher at 425 °C than 475 °C, which resulted in slightly higher oxygen content in bio-oil. The pH of aqueous phase obtained at 475 °C was 7.37 which is the highest reported for any lignocellulosic biomass pyrolysis oils.
Asunto(s)
Asclepias/química , Calor , Termogravimetría/métodos , Reactores Biológicos , Espectroscopía de Resonancia Magnética con Carbono-13 , Cinética , Aceites de Plantas/análisis , Espectroscopía de Protones por Resonancia MagnéticaRESUMEN
A combined analytical study of potsherds excavated from different archaeological sites of Tamilnadu (Kavalapatti, Nattapuraki and Thamaraikulam villages), India are analyzed by spectroscopic techniques such as FTIR, X-ray diffraction, thermogravimetric analysis (TGA) and Scanning Electron Microscope (SEM) coupled with Energy Dispersive Spectrometer (EDS). FTIR and XRD techniques have been attempted to characterize the mineralogical composition, firing temperature and firing conditions of the archaeological potsherds. Thermogravimetric analysis (TGA) is the complementary study to estimate the firing temperature from characteristic thermal reactions in potsherds under controlled firing in inert gas atmosphere. Further, Scanning Electron Microscopy (SEM) equipped and coupled with an Energy Dispersive Spectrometer (EDS) to analyze internal morphology and chemical composition of the potsherds was used. From the results of the above techniques, the firing temperatures of potsherds were found to be greater than 650°C.
Asunto(s)
Arqueología/métodos , Cerámica/química , Cerámica/historia , Historia Antigua , India , Microscopía Electrónica de Rastreo/métodos , Minerales/química , Minerales/historia , Espectrometría por Rayos X/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Termogravimetría/métodos , Difracción de Rayos X/métodosRESUMEN
Flavor plays an important role and has been widely used in foods. Encapsulation can prevent the loss of volatile aromatic ingredients, provide protection and enhance the stability of the flavor. Kinetic and thermodynamic parameters are helpful in understanding the mechanism of molecular recognition between hosts and guests. This work focused on the study of production of a sweet orange flavor-ß-cyclodextrin (CD) inclusion complex, and investigated the combination of flavor and ß-CD by thermogravimetric analysis. Pyrolysis characteristics, kinetic and thermodynamic parameters of the flavor-ß-CD inclusion complex were determined. The results showed that the flavor-ß-CD inclusion complexes can form large aggregates in water. During thermal degradation of blank ß-CD and flavor-ß-CD inclusion complex, three main stages can be distinguished. The thermogravimetric (TG) curve of blank ß-CD shows a leveling-off from room temperature to 250°C, while the TG curve of flavor-ß-CD inclusion complex is downward sloping in this temperature range.
Asunto(s)
Citrus sinensis , Aromatizantes/síntesis química , Aceites de Plantas/síntesis química , beta-Ciclodextrinas/síntesis química , Termogravimetría/métodosRESUMEN
Collagen-Chitosan (COL-CS) scaffolds supplemented with different concentrations (0.1-0.5%) of aloe vera (AV) were prepared and tested in vitro for their possible application in tissue engineering. After studying the microstructure and mechanical properties of all the composite preparations, a 0.2% AV blended COL-CS scaffold was chosen for further studies. Scaffolds were examined by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and thermogravimetry analysis (TGA) to understand the intermolecular interactions and their influence on the thermal property of the complex composite. Swelling property in phosphate buffered saline (pH 7.4) and in vitro biodegradability by collagenase digestion method were monitored to assess the stability of the scaffold in a physiological medium in a hydrated condition, and to assay its resistance against enzymatic forces. The scanning electron microscope (SEM) image of the scaffold samples showed porous architecture with gradual change in their morphology and reduced tensile properties with increasing aloe vera concentration. The FTIR spectrum revealed the overlap of the AV absorption peak with the absorption peak of COL-CS. The inclusion of AV to COL-CS increased the thermal stability as well as hydrophilicity of the scaffolds. Cell culture studies on the scaffold showed enhanced growth and proliferation of fibroblasts (3T3L1) without exhibiting any toxicity. Also, normal cell morphology and proliferation were observed by fluorescence microscopy and SEM. The rate of cell growth in the presence/absence of aloe vera in the scaffolds was in the order: COL-CS-AV > COL-CS > TCP (tissue culture polystyrene plate). These results suggested that the aloe vera gel-blended COL-CS scaffolds could be a promising candidate for tissue engineering applications.
Asunto(s)
Aloe/metabolismo , Quitosano/química , Colágeno/química , Extractos Vegetales/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Células 3T3-L1 , Animales , Materiales Biocompatibles/química , Biodegradación Ambiental , Rastreo Diferencial de Calorimetría/métodos , Adhesión Celular , Proliferación Celular , Colagenasas/química , Liofilización , Concentración de Iones de Hidrógeno , Ratones , Microscopía Electrónica de Rastreo/métodos , Poliestirenos/química , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Resistencia a la Tracción , Termogravimetría/métodosRESUMEN
The present study aims to explore the physico-chemical properties of Mesua ferrea L. (Iron wood tree) deoiled cake (MFDC) and decomposition parameters for thermochemical methods of conversion. The physico-chemical characteristics of MFDC were investigated by bomb calorimetry, TG/DTA (10, 20 and 40°C min(-1)), elemental analysis (CHN) and FTIR spectroscopy. The proximate composition was calculated using standard ASTM methodology. The temperature profile, activation energy (E), pre-exponential factor (A) and reaction order (n) for the active pyrolysis zone of the species under investigation have been provided for the respective heating rates using Arrhenius, Coats-Redfern, Flynn-Wall-Ozawa (FWO) and Global independent reactions model. The current investigation suggests that within the realm of existing biomass conversion technologies, MFDC can be used as a feedstock for thermochemical conversion.