The effect of co-encapsulation of Lactobacillus rhamnosus GG ATCC 53103 with inulin on alginate/chitosan matrix: the viability in fermented soy blend and simulated digestive system

This research verified the ability of Lactobacillus rhamnosus encapsulated with inulin to tolerate the simulated digestive system and their viability in a soy blend. Probiotic encapsulated in alginate-chitosan matrix without inulin presented a better encapsulation efficiency (80.92%) than encapsulation with inulin (57.39%). On the 28th day, the count of probiotics decreased by 3.42 and 1.99 logarithmic cycles of free and encapsulated cells without inulin, respectively. In contrast, the microorganisms encapsulated with inulin showed an increase of 1.26 logs CFU g⁻¹. During gastrointestinal simulation, cell counts decreased by 0.78, 1.55 and 1.95 CFU g⁻¹ logs for encapsulated cells without inulin, free and encapsulated with inulin, respectively. Sensory panellists liked the fermented soy blend with encapsulated lactobacilli, and this result shows the possibility to create new probiotic foods of plant origin. Therefore, the alginate/chitosan matrix can be considered adequate for the encapsulation of L. rhamnosus. The inulin reduces the encapsulation efficiency and increases the cell loss in gastrointestinal simulation. Considering cellular losses, the best option for preparing a fermented soy blend is to use L. rhamnosus encapsulated without inulin.     

Liquid chromatographic determination of caffeine and adrenergic stimulants in food supplements sold in Brazilian e-commerce for weight loss and physical fitness

Methyl-xanthines and adrenergic stimulants, such as caffeine and synephrine, are commonly added to food supplements due to their stimulating and thermogenic effects. In addition, the abusive consumption of food supplements with ergogenic and aesthetic purposes has been observed worldwide. This work describes the study of caffeine, p-synephrine, hordenine, octopamine, tyramine, ephedrine and salicin as stimulants in dietary supplements marketed in Brazil for weight loss and physical fitness claims. A total of 94 different products were acquired from 30 Brazilian websites. Thus, the sampling of marketed supplements was performed in virtual commerce (e-commerce) with claims of weight loss, appetite reduction, fat burning and metabolism acceleration. The developed analytical method involved the separation of the stimulants by HPLC with diode array detection (HPLC-DAD) by using a gradient elution of flow rate (0.7–2.5 ml min^?1) and mobile phase composition (0.1% H₃PO₄/methanol). The validated method was applied to the study of 46 dietary supplements. Caffeine, p-synephrine and ephedrine were found to be present as stimulants in 52% of the studied samples marketed as encapsulated or bulk forms. Caffeine was found to be present in concentrations that represent doses from 25.0 to 1476.7 mg day^–1. Synephrine was found in concentrations that represent doses from 59.1 to 127.0 mg day^–1. Ephedrine was found to be associated with caffeine in one formulation at a concentration representing a 26.1 mg day^–1 dosage.     

A new prefabricated external thermal insulation composite board with ceramic finishing for buildings retrofitting

Given the high energy consumption connected to old buildings and their large environmental impact, there is a strong need for effective solutions for the building envelope retrofitting. Among these solutions, external thermal insulation composite systems (ETICS) have found large application in recent decades. In this paper a new kind of large-size thermal insulation composite boards, prefabricated using porcelain stoneware slab finishing, was developed. Different thermal insulating materials and adhesives, with and without glass fibre mesh, were tested by both current methodologies and purposely designed tests, in order to assess their physical–mechanical properties and durability performance, finally selecting the most suitable materials for the composite board. The strong points of this composite board are mainly: (i) its short placing time and improved execution quality, due to prefabrication; (ii) its high aesthetical value; (iii) its high durability, as the finishing layer is mostly insensible to weathering. The results highlight the good performances of the prefabricated composite board developed in this study (generally higher than current ETICS). The testing procedure followed in this study is also meant to give a contribution to the establishment of methodologies for the selection and durability assessment of materials for the building envelope retrofitting.     

Remote sensing of wetlands in South America: status and challenges

South America has a large proportion of wetlands compared with other continents. While most of these wetlands were conserved in a relatively good condition until a few decades ago, pressures brought about by land use and climate change have threaten their integrity in recent years. The aim of this article is to provide a bibliometric analysis of the available scientific literature relating to the remote sensing of wetlands in South America. From 1960 to 2015, 153 articles were published in 63 different journals, with the number of articles published per year increasing progressively since 1990. This rise is also paralleled by an increase in the contribution of local authors. The most intensively studied regions are the wetland macrosystems of South American mega-rivers: the Amazon and Paraná Rivers, along with the Pantanal at the headwaters of Paraguay River. Few studies spanned more than two countries. The most frequent objectives were mapping, covering all types of wetlands with optical data, and hydrology, focusing on floodplain wetlands with microwave data as the preferred data source. The last decade substantial growth reflects an increase in technological and scientific capacities. Nevertheless, the state of the art regarding the remote sensing of wetlands in South America remains enigmatic. Fundamental questions and guidelines which may contribute to the understanding of the functioning of these ecosystems are yet to be fully defined and there is considerable dispersion in the use of data and remote-sensing approaches.     

Surface‐enhanced fluorescence of in situ synthesized polysilanesilver nanoparticles

To produce surface plasmons, silver nanoparticles are synthesized in situ in a pseudo‐template system based on polyhydrosilanes. Adsorption on the silver nanoparticle surface produces a thin layer of polymer with properties different from those of bulk polysilane. The metal‐adsorbed polymer layer serves as a spacer between the polysilane fluorophore and the plasmonic nanoparticle. This prevents quenching of the polysilane emission and leads to a strong surface‐enhanced fluorescence through coupling of surface plasmons having a resonance frequency that matches the emission frequency of the polymeric emitter. Copyright © 2012 Society of Chemical Industry     

Variation in fatty acid composition of ewes' colostrum and mature milk fat

Temporal content variations of approximately 70 C4–C24 fatty acids (FA) in colostrum and milk of ewes consuming winter diet were determined by gas chromatography. The content of monounsaturated, polyunsaturated and straight-chain saturated FA 14:0–16:0 in colostrum was higher whereas the content of 4:0–12:0, 18:0 and branched-chain saturated FA 15:0–17:0 was lower than that in mature milk. The effect of ewe breed on the FA profiles was not significant. The composition of FA changed most significantly 1–2 days after lambing in agreement with the time schedule of colostrum formation. Nevertheless, the content of FA further successively changed up to approximately the 6th day of lactation, whereas further changes up to the 60th day of lactation were smaller. This is consistent with the recommendation that ewes' milk is suitable for human consumption after six-to-eight days of lactation. The higher contents of palmitic and myristic acids in colostrum compared with mature milk suggest that FA composition in colostrum matches the changing needs of the growing lambs.     

In vitro inhibition of dipeptidyl peptidase IV by peptides derived from the hydrolysis of amaranth (Amaranthus hypochondriacus L.) proteins

Bioactive compounds present in foods could potentially have beneficial effects on human health. In this study we report the in vitro inhibitory capacity of peptides released from amaranth seed proteins after enzymatic digestion, against dipeptidyl peptidase IV (DPPIV); an enzyme known to deactivate incretins, hormones involved in insulin secretion. Other seeds, such as soybean, black bean, and wheat were also tested. The highest inhibition of DPPIV was observed with amaranth peptides released after simulated gastrointestinal digestion, showing an IC₅₀ of 1.1 mg/mL in a dose-dependent manner. In silico tryptic digestion of amaranth globulins was carried out releasing peptides larger than 13 residues. Some of these peptides were used for the in silico prediction of their binding modes with DPPIV. Docking models showed that the possible mechanism of globulin peptides to inhibit DPPIV was through blocking the active dimer formation. Peptides were also found inside the major cavity where the natural substrates reach the catalytic site of the enzyme. This is the first report of the identification of inhibitory DPPIV peptides from amaranth hydrolysates and the prediction of their binding modes at the molecular level, leading to their possible use as functional food ingredients in the prevention of diabetes.