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The purification and recovery of bioactive compounds in food and food waste has been a growing topic within the literature. One of the most used techniques for these processes is through the application of macroporous polymeric resins (MPRs). MPRs have high adsorption and desorption capacities for substances such as polyphenols and sugars that are present in extracts and industrial effluents. There are currently several resins on the market (copolymers of styrenedivinylbenzene, acrylic, sulfonic, or cyanamide); however, a lack of information in the literature regarding the efficiency of analyte recovery and the different physicochemical characteristics of the MPRs means that no broad correlations have been made. Upon compiling the information gained from a comprehensive bibliographic review, using databases such as ScienceDirect and Web of Science, it was possible to classify the different types of resins. In addition, this review will discuss the use of isothermal equations (Langmuir and Freundlich) in experimental data, which can provide quantitative and qualitative parameters of the processes involving the analyte and the MPR. [Display omitted] • Macroporous polymeric resin (MPR) is a tool that helps the analysis of food samples. • MPR allows adjustments of the adsorption and desorption processes. • Recovery of polyphenols and sugars has been shown to be efficient in complex matrices. • We hope to help researchers in choosing the ideal resin. [ABSTRACT FROM AUTHOR]

[Display omitted] • Furanoid glycosylated diterpenes (FGD) from coffee was analyzed by TLC-MS. • A methodology for extracting and detecting FGD was developed. • Four FGD were detected after concentration step in macroporous polymeric resin. • QuEChERS allowed less consumption of solvents and reagents at FGD analysis in coffee. Four furanoid glycosylated diterpenes (mascaroside I, mascaroside III, mascaroside IV and mascaroside V) were extracted from green grains of Coffea arabica after clean up steps with organic solvents (chloroform/acetone and 80 % ethanol) and concentrated with the aid of macroporous polymeric resins (XAD-2) in column. The identification of compounds has been extensively tested with the aid of hyphenated spectroscopic techniques, such as TLC-MS and ESI-HRMS. The methodology employed was shown to be efficient (81 % recovery after column) and robust (molecular ions of compounds with error <5 ppm), fitting the QuEChERS concept. [ABSTRACT FROM AUTHOR]

Abstract: Larvae of various coastal fish undergo immigration from spawning grounds towards estuarine nurseries. Several environmental factors can have an important impact on survival at this stage making it crucial for recruitment. Generalized linear models were applied in order to investigate the relation between river drainage, sea surface temperature (SST), NAO index and the North-South wind component intensity, over the two months prior to the estuarine colonization peak, and the densities of Platichthys flesus, Dicentrarchus labrax, Diplodus vulgaris and Diplodus bellottii in the nursery grounds based on a discontinuous historical dataset (from 1978 to 2006), for the Tagus estuary. The relation between SST over the 12 months prior to the estuarine colonization peak and fish densities in the nurseries was also investigated, as it integrates the periods of spawning stock maturation, spawning and larval immigration. While SST over the prior 12 months was negatively correlated with the abundance of P. flesus, it was positively correlated with the abundance of D. bellottii. Abundance of D. vulgaris was positively correlated with SST in the two months prior to the estuarine colonization peak, while the abundance of D. labrax was positively correlated with river drainage. The relations between SST and the abundance of P. flesus, a cold-water species with declining densities, and the subtropical species D. bellottii and D. vulgaris, which are increasing in abundance, are indicative of species abundance alterations related to climate warming. Dicentrarchus labrax will probably also be affected by climate change because of lowered precipitation and consequently river drainage. [Copyright &y& Elsevier]

Abstract: The respiratory chain of some prokaryotes was shown to be organized in supercomplexes. This association has been proposed to improve enzyme stability and the overall efficiency of the oxidative phosphorylation process. Here, we have revisited recent data on the supercomplexes of Bacillus subtilis respiratory chain, by means of 1D and 2D-BN-PAGE, sucrose gradient fractionation of solubilized membranes, and mass spectrometry analysis of BN-PAGE bands detected in gel for succinate and cytochrome c oxidoreductase activities. The cytochrome bc:caa 3 oxygen oxidoreductase supercomplex was observed in different stoichiometries, (bc)4:(caa 3)2, (bc)2:(caa 3)4 and 2[(bc)2:(caa 3)4], suggesting for the first time the string association model of supercomplexes in a Gram positive bacterium. In addition, the presence of a succinate:quinone oxidoreductase:nitrate reductase supercomplex was confirmed by the co-localized succinate:nitroblue tetrazolium and methylviologen:nitrate oxidoreductase activities detected in gel and corroborated by LC-MS/MS analysis. [Copyright &y& Elsevier]

Decoupling growth from product synthesis is a promising strategy to increase carbon partitioning and maximize productivity in cell factories. However, reduction in both substrate uptake rate and metabolic activity in the production phase are an underlying problem for upscaling. Here, we used CRISPR interference to repress growth in lactate-producing Synechocystis sp. PCC 6803. Carbon partitioning to lactate in the production phase exceeded 90%, but CO 2 uptake was severely reduced compared to uptake during the growth phase. We characterized strains during the onset of growth arrest using transcriptomics and proteomics. Multiple genes involved in ATP homeostasis were regulated once growth was inhibited, which suggests an alteration of energy charge that may lead to reduced substrate uptake. In order to overcome the reduced metabolic activity and take advantage of increased carbon partitioning, we tested a novel production strategy that involved alternating growth arrest and recovery by periodic addition of an inducer molecule to activate CRISPRi. Using this strategy, we maintained lactate biosynthesis in Synechocystis for 30 days in a constant light turbidostat cultivation. Cumulative lactate titers were also increased by 100% compared to a constant growth-arrest regime, and reached 1 g/L. Further, the cultivation produced lactate for 30 days, compared to 20 days for the non-growth arrest cultivation. Periodic growth arrest could be applicable for other products, and in cyanobacteria, could be linked to internal circadian rhythms that persist in constant light. • CRISPRi to arrest growth and activate lactate synthesis. • Growth-arrested cells show decreased metabolic rate. • Cycling repression increases production rate and duration. • ATP imbalance implicated in reduced metabolic activity. [ABSTRACT FROM AUTHOR]

Abstract To fill the "green absorption gap", a green absorbing proteorhodopsin was expressed in a PSI-deletion strain (ΔPSI) of Synechocystis sp. PCC6803. Growth-rate measurements, competition experiments and physiological characterization of the proteorhodopsin-expressing strains, relative to the ΔPSI control strain, allow us to conclude that proteorhodopsin can enhance the rate of photoheterotrophic growth of ΔPSI Synechocystis strain. The physiological characterization included measurement of the amount of residual glucose in the spent medium and analysis of oxygen uptake- and production rates. To explore the use of solar radiation beyond the PAR region, a red-shifted variant Proteorhodopsin-D212N/F234S was expressed in a retinal-deficient PSI-deletion strain (ΔPSI/ΔSynACO). Via exogenous addition of retinal analogue an infrared absorbing pigment (maximally at 740 nm) was reconstituted in vivo. However, upon illumination with 746 nm light, it did not significantly stimulate the growth (rate) of this mutant. The inability of the proteorhodopsin-expressing ΔPSI strain to grow photoautotrophically is most likely due to a kinetic rather than a thermodynamic limitation of its NADPH-dehydrogenase in NADP+-reduction. Highlights • Proteorhodopsin expression increases growth rate of a ∆PSI Synechocystis strain with at least 16 %. • Proteorhodopsin contributes to proton motive force generation in vivo in Synechocystis. • A transgenic Synechocystis strain has been generated that can absorb infrared light. • 'Reversed electron transfer' through NDH-1 could not be demonstrated in Synechocystis. [ABSTRACT FROM AUTHOR]