Chemical properties of 11 date cultivars and their corresponding fiber extracts

Date palm fruit from 11 Tunisian cultivars (Phoenix dactylifera L.) were analyzed for their main chemical composition. Results showed that date fruits were rich in sugar (79.93 - 88.02 g/100 g dry matter), fiber(8.09 - 20.25 g/100 g dry matter) and ash (1.73 - 2.59 g/100 g dry matter). Mineral fraction was dominated by potassium and sugar fraction was dominated by reducing sugar (glucose, fructose) except for Deglet Nour, Kentichi and Bajo which are rich in sucrose. Date fiber concentrates (DFC) were extracted and analyzed for their proximate content (moisture, fiber, protein, lipid and ash) and some functional properties such as water holding capacity (WHC) and oil holding capacity (OHC). DFC presented high dietary fiber content (90.71 - 93.92 g/100g dry matter). Protein and lipid contents (dry matter basis) ranged between 3.66 and 6.06 g/100 g and between 0.35 and 1.08 g/100 g, respectively. DFC presentedhigh WHC (6.20 g water/g dry fiber) and high OHC (1.80 g oil/g dry fiber). Results showed that dates could be a valuable source of highly techno-functional fibers that could be used in food formulations

From community approaches to single-cell genomics: the discovery of ubiquitous hyperhalophilic Bacteroidetes generalists

The microbiota of multi-pond solar salterns around the world has been analyzed using a variety of culture-dependent and molecular techniques. However, studies addressing the dynamic nature of these systems are very scarce. Here we have characterized the temporal variation during 1 year of the microbiota of five ponds with increasing salinity (from 18% to >40%), by means of CARD-FISH and DGGE. Microbial community structure was statistically correlated with several environmental parameters, including ionic composition and meteorological factors, indicating that the microbial community was dynamic as specific phylotypes appeared only at certain times of the year. In addition to total salinity, microbial composition was strongly influenced by temperature and specific ionic composition. Remarkably, DGGE analyses unveiled the presence of most phylotypes previously detected in hypersaline systems using metagenomics and other molecular techniques, such as the very abundant Haloquadratum and Salinibacter representatives or the recently described low GC Actinobacteria and Nanohaloarchaeota. In addition, an uncultured group of Bacteroidetes was present along the whole range of salinity. Database searches indicated a previously unrecognized widespread distribution of this phylotype. Single-cell genome analysis of five members of this group suggested a set of metabolic characteristics that could provide competitive advantages in hypersaline environments, such as polymer degradation capabilities, the presence of retinal-binding light-activated proton pumps and arsenate reduction potential. In addition, the fairly high metagenomic fragment recruitment obtained for these single cells in both the intermediate and hypersaline ponds further confirm the DGGE data and point to the generalist lifestyle of this new Bacteroidetes group.This work was supported by the projects CGL2012-39627-C03-01 and 02 of the Spanish Ministry of Economy and Competitiveness, which were also co-financed with FEDER support from the European Union. TG group research is funded in part by a grant from the Spanish Ministry of Economy and Competitiveness (BIO2012-37161), a grant from the Qatar National Research Fund grant (NPRP 5-298-3-086) and a grant from the European Research Council under the European Union’s Seventh Framework Programme (FP/2007-2013)/ERC (grant agreement no. ERC-2012-StG-310325)

Chitosan-coated mesoporous MIL-100(Fe) nanoparticles as improved bio-compatible oral nanocarriers

Nanometric biocompatible Metal-Organic Frameworks (nanoMOFs) are promising candidates for drug delivery. Up to now, most studies have targeted the intravenous route, related to pain and severe complications; whereas nanoMOFs for oral administration, a commonly used non-invasive and simpler route, remains however unexplored. We propose here the biofriendly preparation of a suitable oral nanocarrier based on the benchmarked biocompatible mesoporous iron(III) trimesate nanoparticles coated with the bioadhesive polysaccharide chitosan (CS). This method does not hamper the textural/ structural properties and the sorption/release abilities of the nanoMOFs upon surface engineering. The interaction between the CS and the nanoparticles has been characterized through a combination of high resolution soft X-ray absorption and computing simulation, while the positive impact of the coating on the colloidal and chemical stability under oral simulated conditions is here demonstrated. Finally, the intestinal barrier bypass capability and biocompatibility of CS-coated nanoMOF have been assessed in vitro, leading to an increased intestinal permeability with respect to the noncoated material, maintaining an optimal biocompatibility. In conclusion, the preservation of the interesting physicochemical features of the CS-coated nanoMOF and their adapted colloidal stability and progressive biodegradation, together with their improved intestinal barrier bypass, make these nanoparticles a promising oral nanocarrier

Biogeography at the limits of life: Do extremophilic microbial communities show biogeographical regionalization?

Aim Biogeographical regions are the fundamental geographical units for grouping Earth's biodiversity. Biogeographical regionalization has been demonstrated for many higher taxa, such as terrestrial plants and vertebrates, but not in microbial communities. Therefore, we sought to test empirically whether microbial communities, or taxa, show patterns consistent with biogeographical regionalization. Location Within halite (NaCl) crystals from coastal solar salterns of western Europe, the Mediterranean and east Africa. Time period Modern (2006–2013). Major taxa studied Archaea. Methods Using high-throughput Illumina amplicon sequencing, we generated the most high-resolution characterization of halite-associated archaeal communities to date, using samples from 17 locations. We grouped communities into biogeographical clusters based on community turnover to test whether these communities show biogeographical regionalization. To examine whether individual taxa, rather than communities, show biogeographical patterns, we also tested whether the relative abundance of individual genera may be indicative of a community's biogeographical origins using machine learning methods, specifically random forest classification. Results We found that the rate of community turnover was greatest over subregional spatial scales (< 500 km), whereas at regional spatial scales the turnover was independent of geographical distance. Biogeographical clusters of communities were either not statistically robust or lacked spatial coherence, inconsistent with biogeographical regionalization. However, we identified several archaeal genera that were good indicators of biogeographical origin, providing classification error rates of < 10%. Main conclusions Overall, our results provide little support for the concept of biogeographical regions in these extremophilic microbial communities, despite the fact that some taxa do show biogeographical patterns. We suggest that variable dispersal ability among the halite-associated Archaea may disrupt biogeographical patterns at the community level, preventing the formation of biogeographical regions. This means that the processes that lead to the formation of biogeographical regions operate differentially on individual microbial taxa rather than on entire communities

An improved method for the preparation of amidines via thiophenylimidic esters

Thioimidates 1a-d were prepared as their hydrobromide salts by the reaction of thiophenol with the corresponding nitriles and then converted to amidines 2a-k on treatment with amines