The activity of Eremanthus erythropappus oil (EO) and some of its compounds and their potential synergistic interaction with ampicillin against different strains of Staphylococcus aureus were investigated. Determination of chemical composition of EO by gas chromatography-mass spectrometry (GC/MS) and bioguided chemical fractionation led to the identification of beta-bisabolene as the main active compound. A synergistic bactericidal activity of EO or beta-bisabolene with ampicillin against Staphylococcus aureus was observed in a time-kill assay. EO and beta- bisabolene have the potential to restore the effectiveness of ampicillin against resistant S. aureus.

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A B S T R A C TMild drying and extrusion processing of side streams from berry juice production can enable retention of valuable compounds in the food chain and reduce waste production. The aim of this study was to evaluate the applicability of using hot air (HA) and microwave assisted hot air (MWHA) drying combined with extrusion for conversion of bilberry press cake into value-added extruded food products. Bilberry press cake was dried at 40°C by HA and MWHA drying to a moisture content of 17 g/100 g. A twin screw extruder (average feed rate 72 g/ min, temperature profile 135-128-89-69°C) was used to extrude products containing organic wholegrain rye flour and 10% or 25% dried bilberry press cake powder. A consumer panel (n = 15) evaluated four extrudates on hedonic and Just-About-Right (JAR) scales, with a main focus on texture properties. The results indicate that different drying techniques implied a difference in processing time (40% reduction with MWHA drying). However, the retention of total phenolics and physical characteristics of extruded snacks containing bilberry powders were independent of drying techniques. In sum, powder of bilberry press cake can be incorporated in cereal based extruded snacks with enhanced phenolic content and potential for palatable sensory properties.

High-Performance Cement Systems consist of cement slurry designs based on engineered particle size distributions that aim to achieve improved mechanical properties and higher chemical resistance compared to traditional cement slurry compositions. The methodology used to obtain High Performance Cement Systems for Oilwells is based on the Compressive Packing Model, where higher content of solids is achieved by using materials having specific particle size distributions. With these higher solids content slurries, a lower proportion of water is required, and thus improved mechanical properties and better chemical resistance can be obtained. The High-Performance Cement Systems, also called High-Packing Cement Systems, in the present work were designed using the Compressive Packing Model, which was developed to design high performance concretes. Various systems for oilwells were designed in this work using Class G Portland Cement, Silica Fume and Hollow Microspheres. The high-performance cement system properties, such as rheological parameters, compressive strength, porosity and acid resistance are shown and compared to traditional cement systems properties. IntroductionThe influence of particle size distribution of solids materials blended with cement on the performance of concrete has been understood by the construction industry since the beginning of last century. There has been an evolution of design protocol since then, evolving from empirical methods to simplified mathematical models to more complex mathematical models in the 1990´s. Many of the models consider the materials as monodispersions or characterize each material by a single diameter (for example, the average diameter) without considering the complete size distribution.There are several models mentioned in the literature, for instance the model of Aim, which was considered as the most suitable for small particles and the model of Toufar, considered as the most appropriate for larger diameter particles [Goltermann, et al., 1997] 1 . Both models consider two classes of aggregates (fine and coarse) consisting of perfect spheres of a uniform diameter. These models optimize the packing of the aggregates only and assume the cement will occupy the voids between the aggregates.Another method described in the literature is called the Rational Method of Lee, which consists of a dynamic method for classification of aggregates, which aims to achieve a maximum density of solids by volume. This model optimizes two classes (in terms of particle size) of aggregates at a time, and considers a typical diameter for each class. If there are more than two classes, the optimization starts with the two classes of larger characteristic diameter. Then, it considers the optimized mix to be a new class of aggregate and proceeds with the optimization with a third class, and so on. The shape, surface charge and compaction of each type of material are considered, and reduced to a single factor called "porosity", which is then used to determine the optimization of aggregate blends. I...

Color is an important characteristic of food. Over the last 15 years, more attention has been paid to natural colorants because of the rising demand for clean-label food products. Anthocyanins, which are a group of phytochemicals responsible for the purple, blue or red hues of many plants, offer a market advantage. In addition, anthocyanin-rich foods are associated with protection against cardiovascular disease, thrombosis, diabetes, cancer, microbial-based disorders, neurological disorders, and vision ailments. However, the real health value of anthocyanins, whether as a natural colorant or a functional ingredient, is dependent on the ultimate bioaccessibility and bioavailability in the human body. Many animal and human clinical studies revealed that, after intake of anthocyanin-rich foods or anthocyanin extracts, only trace amounts (< 1% of ingested content) of anthocyanins or their predicted metabolites were detected in plasma after a standard blood draw, which was indicative of low bioavailability of anthocyanins. Protein binding to anthocyanins is a strategy that has recently been reported to enhance the ultimate bioactivity, bioaccessibility, and bioavailability of anthocyanins as compared to anthocyanins delivered without a protein carrier. Therefore, in this review, we address anthocyanin properties in food processing and digestion, anthocyanin-protein complexes used in food matrices, and changes in the bioaccessibility and bioavailability of anthocyanins when bound into anthocyanin-protein complexes in foods. Finally, we summarize the challenges and prospects of this delivery system for anthocyanin pigments.

Bilberries are a rich natural source of phenolic compounds, especially anthocyanins. The press cake obtained during the processing of bilberry juice is a potential source of phytochemicals. The objective of this study was to evaluate different drying techniques and the fractionation of bilberry press cake powder toward obtaining phenolic‐rich ingredients for incorporation into value‐added food products. The derived powders were dispersed in water and dairy cream, to investigate the effects of drying and fractionation on the dispersibility and solubility of phenolic compounds. The drying techniques, hot air drying and microwave drying, applied on bilberry press cake reduced the content of total phenolics and anthocyanins. The degradation was, however, consistently small and similar for both techniques. The major anthocyanins detected in the samples were stable during drying and fractionation treatments. Fractionation of the press cake powder affected the total apparent phenolic content and composition of the different fractions. The highest phenolic content (55.33 ± 0.06 mg g −1 DW ) and highest anthocyanin content (28.15 ± 0.47 mg g −1 DW ) were found in the fractions with the smallest particle size (<500 μm), with delphinidin‐3‐O‐galactoside being the most abundant anthocyanin. Dispersibility of all dried powder samples was higher in dairy cream than water, and the highest level of anthocyanins was measured in samples from the powder with the smallest particle size (<500 μm), dispersed in cream. The application of drying, milling and fractionation was found to be a promising approach to transform bilberry press cake into stable and deliverable ingredients that can be used for fortification of food products with high levels of phenolic compounds.

Berry fruits, such as strawberries and blueberries, are rich sources of anthocyanins. Several studies have been made on the impact of non-thermal treatments on safety, shelf-life and nutritional characteristics of such products, but the effects of these processes on anthocyanin stability during digestion in the gastrointestinal tract are still not completely clear. The aim of this study was to assess the recovery of anthocyanins after simulated gastrointestinal digestion of (1) strawberry samples, pre-treated with pulsed electric field (PEF) at 100 or 200 V·cm−1, prior to osmotic dehydration (OD), and (2) blueberry samples coated with chitosan and procyanidin. After digestion, a significantly higher content of cyanidin-3-O-glucoside and malvidin-3-O-glucoside was quantified by LC-MS/MS in processed strawberry and blueberry samples, compared with the controls. The highest recovery of cyanidin-3-O-glucoside was detected in digested strawberry samples osmotically dehydrated with trehalose. The recovery of malvidin-3-O-glucoside was highest in digested blueberries coated with chitosan and stored for 14 days, compared with untreated samples or samples coated with chitosan and procyanidin. Our study shows the potential of mild PEF treatments combined with OD, or the use of edible coating, to obtain shelf-stable products without substantially affecting the composition or the stability of anthocyanins during digestion in the upper gastrointestinal tract.

Many studies suggest anthocyanins may prevent the development of several diseases. However, anthocyanin bioactivity against cellular stress is not fully understood. This study aimed to evaluate the protective effect of berry anthocyanins on stressed cells using Saccharomyces cerevisiae. The impact of in vitro gastrointestinal digestion on anthocyanin profiles was also assessed. Bilberry and blackcurrant had higher anthocyanin levels than raspberry and strawberry, but digestion reduced the detected anthocyanins by approximately 90%. Yeast cells with and without digested or nondigested anthocyanin extracts were exposed to H2O2 and examined for survival. In the presence of anthocyanins, particularly from digested strawberry, a significant increase in cell survival was observed, suggesting that the type and levels of anthocyanins are important factors, but they also need to undergo gastrointestinal (GI) structural modifications to induce cell defence. Results also showed that cells need to be exposed to anthocyanins before the stress was applied, suggesting induction of a cellular defence system by anthocyanins or their derivatives rather than by a direct antioxidative effect on H2O2. Overall, data showed that exposure of severely stressed yeast cells to digested berry extracts improved cell survival. The findings also showed the importance of considering gastrointestinal digestion when evaluating anthocyanins’ biological activity.