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Polyaniline (PAni) is a conductive polymer with colorimetric properties, which can be combined with biopolymers to form novel composite materials. These materials can be used as a colorimetric sensor/indicator in the identification of different kinds of analytes. The present study aimed to develop a film of PAni and gum Arabic (GA) by electrochemical method to evaluate its potential use in a colorimetric sensor for ammonia vapor (NH3). The composite PAni/GA was prepared by electrochemical polymerization on a gold surface using the cyclic voltammetry technique. The stability of the films was evaluated in acid (HCl 0.1 mol L-1) after 25 imaging cycles. Strongly acidified gum arabic solution (pH 0.0) and a sweep speed of 10 mV s-1 caused higher current density in the film formation. The morphology of the films was observed by SEM and the presence of cracks in its structure can favor the entry of gases. The response of the composite in the presence of NH3 was measured using a colorimeter. The PAni/GA composite is a promising and rapid tool for use in colorimetric sensors in the detection of NH3. La polianilina (PAni) es un polímero conductor con propiedades colorimétricas, que puede combinarse con biopolímeros para formar nuevos materiales compuestos. Estos materiales se pueden utilizar como sensor/indicador colorimétrico en la identificación de diferentes tipos de analitos. El presente trabajo tuvo como objetivo desarrollar una película de PAni y goma arábiga (GA) por método electroquímico para evaluar su potencial uso en un sensor colorimétrico para vapor de amoníaco (NHs). El composite PAni/GA se preparó mediante polimerización electroquímica sobre superficie de oro utilizando la técnica de voltamperometría cíclica. La estabilidad de la película se evaluó en ácido (0,1 mol L-1 HCl) después de 25 ciclos de formación de imágenes. La solución de goma arábiga fuertemente acidificada (pH 0,0) y una velocidad de barrido de 10 mV s-1 provocaron una mayor densidad de corriente en la formación de la película. La morfología de las películas fue observada por SEM y la presencia de grietas en su estructura puede favorecer la entrada de gases. La respuesta compuesta en presencia de NH3 se midió utilizando un colorímetro. El compuesto PAni/GA es una herramienta prometedora y rápida para su uso en sensores colorimétricos en la detección de NH3. A polianilina (PAni) é um polímero condutor com propriedades colorimétricas, que pode ser combinada com biopolímeros para formar novos materiais compósitos. Esses materiais podem ser usados ​​como sensor/indicador colorimétrico na identificação de diferentes tipos de analitos. O presente trabalho teve como objetivo desenvolver um filme de PAni e goma arábica (GA) por método eletroquímico para avaliar seu potencial de uso em um sensor colorimétrico para vapor de amônia (NH3). O compósito PAni/GA foi preparado por polimerização eletroquímica em superfície de ouro utilizando a técnica de voltametria cíclica. A estabilidade dos filmes foi avaliada em ácido (HCl 0,1 mol L-1) após 25 ciclos de imagem. A solução de goma arábica fortemente acidificada (pH 0,0) e uma velocidade de varredura de 10 mV s-1 causaram maior densidade de corrente na formação do filme. A morfologia dos filmes foi observada por MEV e a presença de trincas em sua estrutura pode favorecer a entrada de gases. A resposta do compósito na presença de NH3 foi medida usando um colorímetro. O compósito PAni/GA é uma ferramenta promissora e rápida para uso em sensores colorimétricos na detecção de NH3.

Edible mushrooms have been increasingly introduced into the human diet, which has driven research into their functional properties. Thus, Agaricus brasiliensis Murill or Agaricus blazei Murill (ABM) is a species native to the Brazilian biome, whose fruiting body has been used not only for dietary purposes, but also in the development of functional foods or as source of molecules of pharmacological interest. The bioactivity of ABM has been related to the presence of polysaccharides, although the contribution of other metabolites cannot be discharged. This work describes the polysaccharides isolation methodology and preparation of the extracts of ABM and their biological activities. Furthermore, it presents a general outline of its characterizations regarding composition, chemical structure and properties in solution. The ABM and its chemical constituents exhibit several biological activities that support their potential use for prevention or treatment of diseases with inflammatory background, such as cancer, diabetes and atherosclerosis. The mechanism of action of the extracts and polysaccharides from ABM is mainly related to a modulation of immune system response or reduction of inflammatory response. This review shows that the ABM has great potential in the pharmaceutical, biotechnological and food sectors that deserves additional research using standardized products.

Açaí is a tropical fruit, typical of the Amazon and has been drawing attention due to its antioxidant capacity and high content of anthocyanins, responsible for several pharmacological and medicinal properties, as well as potential use as a natural dye. Due to the high perishability, the development of new products from the açaí power, which present greater stability to the storage time are being produced. The evaluation period was 25 days at a temperature of 25°C. The following parameters were evaluated: ascorbic acid, chlorophyll, total anthocyanins, total flavonoids, total polyphenols and antioxidant activity by ABTS●+ and DPPH● methods. Microbiological analysis were performed for Coliforms at 35°C and 45°C, Mesophiles, Staphylococcus coagulase positive, Molds, Yeasts, and Salmonella sp. The contents of ascorbic acid, total polyphenols and flavonoids differed statistically (p ˂ 0.05) from each other, throughout the storage. However, the antioxidant activity by the DPPH● method remained stable and the microbiological analysis remained within the current legislative standards. It is concluded that the açaí powder maintained its properties throughout the storage, being an excellent source of bioactive and phenolic compounds. El açaí es una fruta tropical, típica de la Amazonía y ha llamado la atención por su capacidad antioxidante y alto contenido de antocianinas, responsable de varias propiedades farmacológicas y medicinales, además de su uso potencial como colorante natural. Debido a la alta perecebilidad, se está desarrollando el desarrollo de nuevos productos a partir de açaí, que ofrece mayor estabilidad y tiempo de almacenamiento, como un polvo. El objetivo de esta investigación fue evaluar la estabilidad del polvo de açaí durante un período de 270 días a una temperatura de 25 ° C. Los siguientes parámetros se evaluaron cada 30 días: ácido ascórbico, clorofila, antocianinas totales, flavonoides totales, polifenoles totales y actividad antioxidante mediante los métodos ABTS●+ y DPPH●. Se realizaron análisis microbiológicos para coliformes a 35 y 45 ° C, mesófilos, estafilococos coagulasa positivos, mohos y levaduras, y Salmonella sp. Los contenidos de ácido ascórbico, polifenoles totales y flavonoides diferían estadísticamente (p

The known biotechnological properties of chitosan and the recent biological activities attributed to polysaccharides from Agaricus brasiliensis have been of interest to obtain films constituted by these two polymers. The glucans obtained from the mushroom inhibited about 96.5% of the ferrous ion, besides not promoting a significant increase of lactate dehydrogenase enzyme (LDH), which indicates that the polysaccharide is able to inhibit the production of radical species and also presents low cytotoxicity to the biological systems. The results of spectroscopy analyses in the infrared region (FTIR) and X-ray diffraction suggest an existing electrostatic interaction between the substances. A reduction in the films’ swelling capacity was observed with an increase in the polysaccharide content in the composition. In addition, scanning electron microscopy (SEM) revealed greater surface density of the films. In convening the biological properties of the substances, it is expected that this study raises interest in evaluating the films and their capacity for healing wounds and burns.

The present objective of the investigation is to evaluate the antihypercholesterolemic activity of the aqueous fruit pulp extract (APE) ofCopernicia prunifera(Miller) H. E. Moore (Arecaceae family). Various chemical characterization methods like thin layer chromatography, Fourier transform infrared spectroscopy,1H and13C NMR, and molecular weight by gel permeation chromatography have been employed to characterize the extracted pectin. The present study demonstrated that hypercholesterolemic diet (HD) created hypercholesterolemia, caused significant increases in body weight, total cholesterol, and low-density lipoprotein, and caused decreases in high-density lipoprotein in serum compared with SD group. Two doses (APE 150 and 300 mg/Kg b.w./day) were administered to hyperlipidemic mice for 90 days. APE reversed body weight changes, changed serum lipids to normal values, and significantly inhibited the changes of lipid peroxidation and inflammation in the liver tissues. The renal parameters analyzed (urea and creatinine) altered by diet were reverted to normal values. Our results revealed that aqueous fruit pulp extracts of carnauba reduced hypercholesterolemia showing a potential preventive effect against cardiovascular diseases without side effects cause.

The beneficial biological effects of cinnamic acid derivatives and the lack of studies on the antioxidant activity and bioavailability of cinnamic esters from carnauba wax, diesters were extracted from carnauba wax powder. Their structural, physical and morphological characteristics, antioxidant activity and in vitro bioaccessibility were measured. p-Methoxycinnamic diester (PCO-C) was identified, which has a crystalline, apolar structure and exhibited significant antioxidant activity (107.27±3.92μM Trolox/g of dry weight) before and after simulated in vitro gastrointestinal digestion and 32.46% bioaccessibility. In human cells, PCO-C (250μg/mL) inhibited the production of intracellular reactive oxygen species, with an effect similar to that of Trolox (80μM). Thermogravimetric analysis showed that PCO-C had high thermal stability and high UV absorption between 250 and 350nm. These results indicate that this compound is promising as an antioxidant for pharmaceutical and food industry applications, such as the development of active packaging and functional foods.

This study aimed to characterize the chemical structure of water-soluble polysaccharide fractions extracted from co-products of acerola, cashew apple, pineapple, mango and passion fruit, evaluating their gastroprotective effect in vivo associated to their antioxidant activity. The results from the structural analysis revealed that all fractions extracted from the co-products were heteropolysaccharides composed by the monosaccharides glucose, arabinose, galactose and d -galacturonic acid, and presented a pectic nature, which was evidenced by the predominant presence of arabinogalactan in their constitutions. The polysaccharides obtained from acerola, cashew apple and pineapple exhibited similarity in their morphology compared to those from mango and passion fruit. The fractions did not show cytotoxic effects for epithelial culture IEC-6A, and stimulated cell growth as visualized by the increase in cellular viability. Notable antioxidant activities were found for cashew apple (147 μM Trolox.g−1), pineapple (80.0 μM Trolox.g−1) and acerola (79.0 μM Trolox.g−1). These same polysaccharides promoted higher preservation of glutathione levels in mice stomach tissue, resulting in its effective protection from the damage caused by ethanol. On the other hand, high malondialdehyde levels were observed in the stomach tissues of the animals treated with the polysaccharides from mango and passion fruit. The co-products from acerola and cashew were able to protect the gastric mucosa of mice from the lesions induced by ethanol. The results found in this research introduce polysaccharide fractions extracted from acerola, cashew apple and pineapple co-products as safe and natural antioxidants, with a high potential to be applied in different industry fields.

Cashew gum (CG) and gelatin (G) films were produced by incorporating ferulic acid (FA), as a cross-linking agent and Cymbopogon citratus essential oil (EO) for application bread packaging. The addition of FA and EO did not significantly affect water vapor permeability (WVP) or opacity. There was a significant decrease in the solubility of the films, possibly due to matrix cross-linking. Morphology revealed films with smooth surfaces and small cross-sections. Characteristic frequencies of CG and G demonstrated the cross-linking identified in infrared (IV). EO cross-linked films showed lower rupture stress than non-EO films. Elongation-at-break increased from 2% (cross-linked) to 140% (cross-linked/EO). CGG/EO packaging was more permeable than commercial packaging (polyethylene), giving bread more harshness. The experimental packaging provided six days of preservation to the bread compared with three days for the commercial packaging. Neral and geranial presented a higher proportion in the crust of the bread, suggesting antimicrobial action.

Polysaccharides constituted predominately of β-(1→6)-glucans were isolated from Agaricus brasiliensis and studied in aqueous medium. It was obtained an intrinsic viscosity value [ η ] of 5.31 mL/g and average viscosimetric molar mass ( M v ) of 3.9×10 4 g/mol. The rheological study under the conditions of low and high shear rate demonstrated a predominant Newtonian behaviour showing a tendency to shear thinning flow behaviour at low shear rates. Physico-chemical parameters such as superficial tension ( γ ), critical micelle concentration (cmc) and superficial pressure ( Л ), as well as free Gibbs energy of micellization (Δ G ) and the entropy of micellization (Δ S ) showed similar characteristic to those found for other polysaccharides with surface tension properties. From the observed surfactant properties of the isolated polysaccharide it was evaluated its capacity to solubilize the drug griseofulvin. AFM images have shown that the glycoproteic complex may dissolve the drug forming self assembly particles with sizes ranging from nano to micrometers. The preliminary tests showed the feasibility of the use of the glucan solutions as solubilizing medium for griseofulvin.

The soluble proteins extracted from the latex of Calotropis procera (LP) have been shown to powerfully ameliorate different inflammatory disorders such as arthritis, cancer and sepsis. In this study, we developed a polyvinyl alcohol-based membrane as an LP delivery system and determined the efficacy of LP in tissue remodeling and healing upon topical treatment in mice. Aqueous polyvinyl alcohol (PVA, 1%, w/v) solution was mixed with LP (0.2% or 1%) while stirring to obtain a biomembrane, which was then applied to wounds. PVA and LP-containing PVA membranes were structurally characterized and standardized by infrared absorption spectroscopy and thermogravimetry. Wound healing parameters included time of healing progress and tissue remodeling (fibroplasia and collagen). LP-containing PVA membrane (0.2% and 1%), but not PVA membrane, significantly accelerated wound healing through faster neo-tissue formation. This process was accompanied by intensified fibroplasia and collagen deposition as revealed by microscopic analyses. It is therefore concluded that topical application of LP on wounds stimulates the healing process and that the use of PVA membranes to carry LP is a reliable approach for topical delivery of pharmacologically active proteins.

Many interesting biological activities have been reported related to the presence of β-glucans from different species of mushrooms. In this work, β-glucans were isolated from the polysaccharide of the fruiting bodies of Agaricus blazei Murill known as Agaricus brasiliensis . β-Glucans were obtained with a specific procedure using thymol. The isolated material was characterized by FTIR assignments which indicate the presence of polysaccharides and some amount of protein in the obtained precipitate. The presence of β-glucans was evidenced by recording the band around 890 cm −1 relative to the deformation of that bond. 1 H and 13 C NMR as well as two-dimensional COSY and HMQC spectra were used for characterization of the β-glucans which showed that the isolated material is constituted mainly by β-(1→6) glucans.

Passion fruit is a fruit originating in the American tropics, is cultivated in countries with tropical and subtropical climates and belongs to the Passifloraceae family and Passiflora gender. One of the methods of cultivation of passion fruit is the organic system, a practice increasingly common in order to combine quality of food products with environmental preservation. Considering the current trends for nutritious foods and fast preparation, the use of dehydrated passion fruit offers an interesting alternative to reduce losses, add value to the product and provide other ways to consume fruit. Based on this information, the objective was to evaluate the stability and the quality of the organic passion fruit powder, obtained by spray drying, during 360 days of storage under room temperature (25 ± 2°C). The passion fruit powder was evaluated every 30 days during the 360 days of storage, for the chemical, physic-chemical and microbiological parameters. The organic passion fruit powder remained stable during the 360 days of storage at room temperature, offering great potential for use due to present adequate retention of ascorbic acid (15.86 mg/100 g), desired hygroscopicity (22.71 g of absorbed water/100 g), low water activity (0.47), stable acid pH (4.16), high levels of ash (4.77%), total sugar (36.94%), total extractable polyphenols (196.17 mg GAE/100 g) and satisfactory microbiological results with absence of coliforms at 35°C and 45°C, Salmonella sp/25 g, mesophilic and Staphylococcus coagulase positive values were less than 10 CFU/g.

The knowledge of the fruit tropical pulps rheological behavior have a great importance for the consumers and food process industries. In this work it was studied the rheological behavior of the cashew apple ( Anacardium occidentale , L.), mango ( Mangifera indica , L) and acerola ( Malpighia emarginata, DC) single strength, frozen and pasteurized pulps. The experimental measurements were carried out in concentric cylinder rheometer and the experimental data were fitted to models of Ostwald-de-Waelle and Bingham. There were evaluated chemical, physical-chemical and microbiological parameters. In this work, in order to adjust the rheological parameters, the model that presented the best description was the Ostwald-de-Waelle for the mango and acerola pulps, and Bingham for cashew apple pulp. The samples presented non-Newtonian and pseudoplastic character. The chemical and physicochemical analysis showed the nutritional value of the studied fruits. The microbiological results presented satisfactory hygienic and sanitary conditions in pulps processing.

The use of natural substances in health applications may be hampered by the difficulties in establishing the mechanisms of action, especially at molecular-level. The protein-polysaccharide complex extracted from the mushroom Agaricus blazei Murill, referred to as CAb, has been considered for treating various diseases with probable interaction with cell membranes. In this study, we investigate the interaction between CAb and a cell membrane model represented by a Langmuir monolayer of dimyristoyl phosphatidic acid (DMPA). CAb affects the structural properties of DMPA monolayers causing expansion and increasing compressibility. In addition, interaction with DMPA polar heads led to neutralization of the electrical double layer, yielding a zero surface potential at large areas per molecule. CAb remained at the interface even at high surface pressures, which allowed transfer of Langmuir-Blodgett (LB) films onto solid supports with the CAb-DMPA mixture. The mass transferred, according to quartz crystal microbalance (QCM) measurements, increased linearly with the number of deposited layers. With UV-vis absorption, fluorescence and FTIR spectroscopies, we confirmed that the LB films contain polysaccharides, proteins and DMPA. Therefore, the CAb biological action must be attributed not only to polysaccharides but also to proteins in the complex.

Aims: Agaricus brasiliensis (previously named Agaricus blazei ss. Heinem), also known as the sun mushroom is native of Southeast Brazil, and is widely consumed, mainly in the form of tea, due to its nutritional and pharmacological properties. In this study, we tested aqueous (AqE) and ethanol (EtOHE) extracts and an isolated polysaccharide (PLS) from the fruiting body of A. brasiliensis, for antiviral activity against poliovirus type 1 in HEp-2 cells. Methods and Results: The evaluation of the time of addition by plaque assay showed that when AqE, PLS and EtOHE were added, just after the virus inoculation (time 0 h), there was a concentration-dependent reduction in the number of plaques up to 50%, 67% and 88%, respectively, with a selectivity index (SI) of 5·4, 9·9 and 12·3, respectively. Conclusions: The test substances showed antiviral activity and were more effective when added during the poliovirus infection. As they had little effect on reducing viral adsorption and did not show any virucidal effect, we suggest that they act at the initial stage of the replication of poliovirus. Significance and Impact of the Study: These results corroborate that basidiomycetes can be a rich source of potential antiviral compounds.

This study aimed to develop beverages of mixed nectars of tropical fruits and to determine the best accepted formulation. The puree blend contents were: cashew apple (12.25-21.00 g 100 g-1); acerola (1.75-10.50 g 100 g-1); and mango (12.25-21.00 g 100 g-1), varying according to a mixture design. The evaluated responses were based on physicochemical, chemical and sensorial determinations. The models for antioxidant activity, overall acceptance, ascorbic acid content, phenolic content and viscosity were statistically signifi cant (P ≤ 0.05). The formulation with 12.25 g of cashew apple puree 100 g-1, 21.00 g of mango puree 100 g-1 and 1.75 g of acerola puree 100 g-1 was the best accepted by the tasters. Mango and cashew apple purees must be present in a greater proportion in the mixture, since they have high fl avour acceptance. The antioxidant activity of mixed nectars was most increased by acerola, followed by cashew apple. A high correlation was observed between antioxidant activity and acerola puree content and there was also a high correlation between antioxidant activity and both ascorbic acid and total phenolic contents.

An efficient route has been developed to isolate water soluble polysaccharides from Agaricus blazei Murill mushroom of Brazilian origin. Using different temperatures: 10, 60 and 100 °C, and precipitation with ethanol, a number of precipitates were extracted which were isolated, purified and fractionated for characterization. The molar mass distribution for the precipitates and fractions from the extraction at 100 °C were determined by GPC. Analysis of the FTIR, 1H NMR and 13C NMR spectra showed a pattern characteristic of glucan–protein complex.

A water soluble polysaccharide and its selective precipitated fractions (F1, F2, and F3) were isolated from hot water extract of fruiting bodies of Agaricus blazei Murril known as Agaricus brasiliensis to evaluate the analgesic activity of the materials in Swiss mice. The isolated material and its fractions were characterized by two-dimensional COSY and HMQC spectra as β-(1→6)-α-(1→4)-glucan-bound-protein polysaccharide constituted mainly by β-(1→6) glucan. The glucan-protein polysaccharide and its fractions were analyzed in relation to the protein, carbohydrate, and mineral elements contents. The analysis of the glucan-protein complex revealed a total carbohydrate content of 36.95% and protein conjugated content of 17.24%. The mineral elements found in larger proportion were K, Na, Ca, P, and Zn. The analgesic activity bioassay of the β-(1→6)-α-(1→4)-glucan bound-protein polysaccharide and its fractions in Swiss mice indicated a significant effect.

Agaricus blazei Murrill, a native mushroom of Brazil, has been widely consumed in different parts of the world due to its anticancer potential. This effect is generally attributed to its polysaccharides; however, the precise structure of these has not been fully characterized. To better understand the relationship between polysaccharide structures and antitumor activity, we investigated the effect of the intraperitoneally (i.p.) or orally (p.o.) administered alpha-(1--4)-glucan-beta-(1--6)-glucan-protein complex polysaccharide from A. blazei alone or in association with 5-fluorouracil (5-FU) in tumor growth using Sarcoma 180 transplanted mice. Hematological, biochemical, and histopathological analyses were performed in order to evaluate the toxicological aspects of the polysaccharide treatment. The polysaccharide had no direct cytotoxic action on tumor cells in vitro. However, the polysaccharide showed strong in vivo antitumor effect. Thus, the tumor growth-inhibitory effect of the polysaccharide is apparently due to host-mediated mechanisms. The histopathological analysis suggests that the liver and the kidney were not affected by polysaccharide treatment. Neither enzymatic activity of transaminases (AST and ALT) nor urea levels were significantly altered. In hematological analysis, leucopeny was observed after 5-FU treatment, but this effect was prevented when the treatment was associated with the polysaccharide. In conclusion, this polysaccharide probably could explain the ethnopharmacological use of this mushroom in the treatment of cancer.

Este trabalho teve como objetivo estudar o comportamento reológico de néctares mistos de caju, manga e acerola nas temperaturas de 8, 15, 25, 35 e 45 °C. Foi utilizado para coleta dos dados experimentais um reômetro rotacional de cilindros concêntricos tipo Searle da Brookfield, modelo R/S plus SST 2000. Os dados foram ajustados ao modelo de Ostwald-de-Waelle. O efeito da temperatura sobre a viscosidade aparente dos néctares foi descrito mediante uma equação análoga à de Arrhenius. As formulações apresentaram comportamento não newtoniano e caráter pseudoplástico, para todas as temperaturas estudadas. Com o aumento da temperatura houve uma tendência a menor ajuste dos dados reológicos ao modelo de Ostwald-de-Waelle. A formulação 1 apresentou redução do índice de consistência com aumento da temperatura, comportamento contrário ao observado para as formulações 2, 4 e 9. As demais formulações apresentaram comportamento não característico.