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Depth-integrated primary productivity (PP) estimates obtained from satellite ocean color-based models (SatPPMs) and those generated from biogeochemical ocean general circulation models (BOGCMs) represent a key resource for biogeochemical and ecological studies at global as well as regional scales. Calibration and validation of these PP models are not straightforward, however, and comparative studies show large differences between model estimates. The goal of this paper is to compare PP estimates obtained from 30 different models (21 SatPPMs and 9 BOGCMs) to a tropical Pacific PP database consisting of ∼ 1000 14C measurements spanning more than a decade (1983-1996). Primary findings include: skill varied significantly between models, but performance was not a function of model complexity or type (i.e. SatPPM vs. BOGCM); nearly all models underestimated the observed variance of PP, specifically yielding too few low PP (< 0.2 g C m- 2 d- 1) values; more than half of the total root-mean-squared model-data differences associated with the satellite-based PP models might be accounted for by uncertainties in the input variables and/or the PP data; and the tropical Pacific database captures a broad scale shift from low biomass-normalized productivity in the 1980s to higher biomass-normalized productivity in the 1990s, which was not successfully captured by any of the models. This latter result suggests that interdecadal and global changes will be a significant challenge for both SatPPMs and BOGCMs. Finally, average root-mean-squared differences between in situ PP data on the equator at 140°W and PP estimates from the satellite-based productivity models were 58% lower than analogous values computed in a previous PP model comparison 6 years ago. The success of these types of comparison exercises is illustrated by the continual modification and improvement of the participating models and the resulting increase in model skill. © 2008 Elsevier B.V.

The 5-year Ocean Regulation of Climate by Heat and Carbon Sequestration and Transports (ORCHESTRA) programme and its 1-year extension ENCORE (ENCORE is the National Capability ORCHESTRA Extension) was an approximately 11-million-pound programme involving seven UK research centres that finished in March 2022. The project sought to radically improve our ability to measure, understand and predict the exchange, storage and export of heat and carbon by the Southern Ocean. It achieved this through a series of milestone observational campaigns in combination with model development and analysis. Twelve cruises in the Weddell Sea and South Atlantic were undertaken, along with mooring, glider and profiler deployments and aircraft missions, all contributing to measurements of internal ocean and air-sea heat and carbon fluxes. Numerous forward and adjoint numerical experiments were developed and supported by the analysis of coupled climate models. The programme has resulted in over 100 peer-reviewed publications to date as well as significant impacts on climate assessments and policy and science coordination groups. Here, we summarize the research highlights of the programme and assess the progress achieved by ORCHESTRA/ENCORE and the questions it raises for the future. This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.

There has been an increasing drive toward better valorising raw biological materials in the context of the sustainability of bio-based industries and the circular economy. As such, microalgae hold the ability to biosynthesise valuable metabolites, which are sought after within the bioenergy, pharmaceuticals, cosmetics or nutrition sectors. Owing to their bioactivities, the xanthophyll pigment fucoxanthin and the omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) have fostered increasing interests in terms of sustainably refining them from natural sources, such as microalgae. Together with the suitability of individual species to industrial cultivation, a key challenge resides in optimizing the yields of these compounds within the microalgal biomass they are retrieved from. The marine diatom Stauroneis sp. LACW24 was batch cultivated into its stationary phase of growth prior to being subjected at high cell density (1 × 10 6  cells mL -1 ) to seven different regimes of light exposure in replenished medium and under nutritional limitation (silica and nitrate) for 12 days. The highest EPA proportions and yields were obtained under blue LED in f/2 medium (16.5% and 4.8 mg g -1 , respectively), double the values obtained under red LED illumination. The fucoxanthin yield was the highest when cells were subjected to blue LEDs (5.9 mg g -1 ), a fourfold increase compared to the nitrogen-limited treatment under white LEDs. These results indicate that a two-stage approach to the batch cultivation of this diatom can be used for enhancing the production of the high-value metabolites fucoxanthin and EPA post-stationary phase., (© 2021 American Institute of Chemical Engineers.)

The flux of CO 2 between the atmosphere and the ocean is often estimated as the air-sea gas concentration difference multiplied by the gas transfer velocity (K 660 ). The first order driver for K 660 over the ocean is wind through its influence on near surface hydrodynamics. However, field observations have shown substantial variability in the wind speed dependencies of K 660 . In this study we measured K 660 with the eddy covariance technique during a ~ 11,000 km long Southern Ocean transect. In parallel, we made a novel measurement of the gas transfer efficiency (GTE) based on partial equilibration of CO 2 using a Segmented Flow Coil Equilibrator system. GTE varied by 20% during the transect, was distinct in different water masses, and related to K 660 . At a moderate wind speed of 7 m s -1 , K 660 associated with high GTE exceeded K 660 with low GTE by 30% in the mean. The sensitivity of K 660 towards GTE was stronger at lower wind speeds and weaker at higher wind speeds. Naturally-occurring organics in seawater, some of which are surface active, may be the cause of the variability in GTE and in K 660 . Neglecting these variations could result in biases in the computed air-sea CO 2 fluxes.

Phosphorus (P) loss from agricultural areas to waterbodies is a worldwide concern. However, the effect of soil source and transport factors, such as clay (C) content and slope (S), on the magnitude of the P transport in Brazilian subtropical soils is still understudied. The objectives of this study were i) to quantify the loss of P fractions by runoff in areas receiving pig slurry application and with variations in S and C content; ii) propose an environmental critical limit model of P (P-threshold) for Brazilian subtropical soils. Thus, two series of experiments were conducted from 2016 to 2018, one under a Nitisol with 642 g kg -1 of C and another under a Cambisol with 225 g kg -1 of C. The treatments were four P rates (0, 56, 112 and 224 kg P ha -1 year -1 ) superficially applied as pig slurry, on Tifton (Cynodon sp) pasture, and three S (10, 20 and 30% in the Nitisol and 15, 25 and 35% in Cambisol). P losses increased in both soils as the S and P rates rose. The Nitisol showed P losses three times higher than the Cambisol. Soil S above 25% promotes P losses at a rate three times higher than in soil below this limit. Therefore, we propose a P-threshold model for Mehlich-1 extractable P levels for Brazilian subtropical soils as: "P-threshold = (42.287 + C) - (0.230 S + 0.0123 C S)" in soils with a S ≤ 25% and "P-threshold = (42.287 + C) - (-0.437 S + 0.039 C S)" in soils with a S >25%, where both C and S are shown in percentage. The soil clay content and slope are aggravating factors to the P transfer process, thus must be considered in suitable models to predict the P losses risk., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Pseudomonas aeruginosa uses quorum sensing (QS) to modulate the expression of several virulence factors that enable it to establish severe infections. The QS system in P. aeruginosa is complex, intricate and is dominated by two main N-acyl-homoserine lactone circuits, LasRI and RhlRI. These two QS systems work in a hierarchical fashion with LasRI at the top, directly regulating RhlRI. Together these QS circuits regulate several virulence associated genes, metabolites, and enzymes in P. aeruginosa. Paradoxically, LasR mutants are frequently isolated from chronic P. aeruginosa infections, typically among cystic fibrosis (CF) patients. This suggests P. aeruginosa can undergo significant evolutionary pathoadaptation to persist in long term chronic infections. In contrast, mutations in the RhlRI system are less common. Here, we have isolated a clinical strain of P. aeruginosa from a CF patient that has deleted the transcriptional regulator RhlR entirely. Whole genome sequencing shows the rhlR locus is deleted in PA80 alongside a few non-synonymous mutations in virulence factors including protease lasA and rhamnolipid rhlA, rhlB, rhlC. Importantly we did not observe any mutations in the LasRI QS system. PA80 does not appear to have an accumulation of mutations typically associated with several hallmark pathoadaptive genes (i.e., mexT, mucA, algR, rpoN, exsS, ampR). Whole genome comparisons show that P. aeruginosa strain PA80 is closely related to the hypervirulent Liverpool epidemic strain (LES) LESB58. PA80 also contains several genomic islands (GI's) encoding virulence and/or resistance determinants homologous to LESB58. To further understand the effect of these mutations in PA80 QS regulatory and virulence associated genes, we compared transcriptional expression of genes and phenotypic effects with isogenic mutants in the genetic reference strain PAO1. In PAO1, we show that deletion of rhlR has a much more significant impact on the expression of a wide range of virulence associated factors rather than deletion of lasR. In PA80, no QS regulatory genes were expressed, which we attribute to the inactivation of the RhlRI QS system by deletion of rhlR and mutation of rhlI. This study demonstrates that inactivation of the LasRI system does not impact RhlRI regulated virulence factors. PA80 has bypassed the common pathoadaptive mutations observed in LasR by targeting the RhlRI system. This suggests that RhlRI is a significant target for the long-term persistence of P. aeruginosa in chronic CF patients. This raises important questions in targeting QS systems for therapeutic interventions.

Compelling evidence is presented that sub-micron picoplankton shape, internal structure and orientation in combination leads to a disproportionate enhancement of differential forward scatter compared with differential side scatter when analyzed with a flow cytometer. Theoretical evidence is provided which results in an order of magnitude amplification in the forward scatter direction, with little or no change in the side scatter: this discounts the possibility of "doublets" caused by multiple particles simultaneously present in the laser beam. Observational evidence from progressively finer filtered seawater samples shows up to three orders of magnitude enhancement in the forward scatter direction and sizes of Prochlorococcus close to that reported in the literature (0.61 ± 0.17 µm). It therefore seems likely that flow cytometrically observed "bi-modal size distributions" of Prochlorococcus are instead the manifestation of intra-population differences in shape (spherical - prolate with preferential alignment) and internal structure (homogenous - heterogenous).

Continental margins are disproportionally important for global primary production, fisheries and CO 2 uptake. However, across the Northeast Atlantic shelves, there has been an ongoing summertime decline of key biota-large diatoms, dinoflagellates and copepods-that traditionally fuel higher tropic levels such as fish, sea birds and marine mammals. Here, we combine multiple time series with in situ process studies to link these declines to summer nutrient stress and increasing proportions of picophytoplankton that can comprise up to 90% of the combined pico- and nanophytoplankton biomass in coastal areas. Among the pico-fraction, it is the cyanobacterium Synechococcus that flourishes when iron and nitrogen resupply to surface waters are diminished. Our field data show how traits beyond small size give Synechococcus a competitive edge over pico- and nanoeukaryotes. Key is their ability to grow at low irradiances near the nutricline, which is aided by their superior light-harvesting system and high affinity to iron. However, minute size and lack of essential biomolecules (e.g. omega-3 polyunsaturated fatty acids and sterols) render Synechococcus poor primary producers to sustain shelf sea food webs efficiently. The combination of earlier spring blooms and lower summer food quantity and quality creates an increasing period of suboptimal feeding conditions for zooplankton at a time of year when their metabolic demand is highest. We suggest that this nutrition-related mismatch has contributed to the widespread, ~50% decline in summer copepod abundance we observe over the last 60 years. With Synechococcus clades being prominent from the tropics to the Arctic and their abundances increasing worldwide, our study informs projections of future food web dynamics in coastal and shelf areas where droughts and stratification lead to increasing nutrient starvation of surface waters., (© 2020 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Background: Brown seaweeds are known to be a rich source of fiber with the presence of several non-digestible polysaccharides including laminarin, fucoidan and alginate. These individual polysaccharides have previously been shown to favorably alter the gut microbiota composition and activity albeit the effect of the collective brown seaweed fiber component on the microbiota remains to be determined., Methods: This study investigated the effect of a crude polysaccharide-rich extract obtained from Laminaria digitata (CE) and a depolymerized CE extract (DE) on the gut microbiota composition and metabolism using an in vitro fecal batch culture model though metagenomic compositional analysis using 16S rRNA FLX amplicon pyrosequencing and short-chain fatty acid (SCFA) analysis using GC-FID., Results: Selective culture analysis showed no significant changes in cultured lactobacilli or bifidobacteria between the CE or DE and the cellulose-negative control at any time point measured (0, 5, 10, 24, 36, 48 h). Following metagenomic analysis, the CE and DE significantly altered the relative abundance of several families including Lachnospiraceae and genera including Streptococcus, Ruminococcus and Parabacteroides of human fecal bacterial populations in comparison to cellulose after 24 h. The concentrations of acetic acid, propionic acid, butyric acid and total SCFA were significantly higher for both the CE and DE compared to cellulose after 10, 24, 36 and 48 h fermentation (p < 0.05). Furthermore, the acetate:propionate ratio was significantly reduced (p < 0.05) for both CD and DE following 24, 36 and 48 h fermentation., Conclusion: The microbiota-associated metabolic and compositional changes noted provide initial indication of putative beneficial health benefits of L. digitata in vitro; however, research is needed to clarify if L. digitata-derived fiber can favorably alter the gut microbiota and confer health benefits in vivo.

Depth-resolved flow cytometric observations have been used to determine the size distribution and refractive index (RI) of picoplankton throughout the Atlantic Ocean. Prochlorococcus frequently showed double size distribution peaks centered on ${0.75 \pm 0.25}$0.75±0.25 and ${1.75 \pm 0.25}\,\,{\rm \unicode{x00B5}{\rm m}}$1.75±0.25µm; the smallest peak diameters were ${\le}{0.65}\,\,{\rm \unicode{x00B5}{\rm m}}$≤0.65µm in the equatorial upwelling with larger cells (${\sim}{0.95}\,\,{\rm \unicode{x00B5}{\rm m}}$∼0.95µm) in the surface layers of the tropical gyres. Synechococcus was strongly monodispersed: the smallest (${\sim}{1.5}\,\,{\rm \unicode{x00B5}{\rm m}}$∼1.5µm) and largest cells (${\sim}{2.25{-}2.50}\,\,{\rm \unicode{x00B5}{\rm m}}$∼2.25-2.50µm) were encountered in the lowest and highest abundance regions, respectively. Typical RI for Prochlorococcus was found to be ${\sim}{1.06}$∼1.06, whereas for Synechococcus surface RI varied between 1.04-1.08 at high and low abundances, respectively.

At present, anti-virulence drugs are being considered as potential therapeutic alternatives and/or adjuvants to currently failing antibiotics. These drugs do not kill bacteria but inhibit virulence factors essential for establishing infection and pathogenesis through targeting non-essential metabolic pathways reducing the selective pressure to develop resistance. We investigated the effect of naturally isolated plant compounds on the repression of the quorum sensing (QS) system which is linked to virulence/pathogenicity in Pseudomonas aeruginosa. Our results show that trans-cinnamaldehyde (CA) and salicylic acid (SA) significantly inhibit expression of QS regulatory and virulence genes in P. aeruginosa PAO1 at sub-inhibitory levels without any bactericidal effect. CA effectively downregulated both the las and rhl QS systems with lasI and lasR levels inhibited by 13- and 7-fold respectively compared to 3- and 2-fold reductions with SA treatment, during the stationary growth phase. The QS inhibitors (QSI) also reduced the production of extracellular virulence factors with CA reducing protease, elastase and pyocyanin by 65%, 22% and 32%, respectively. The QSIs significantly reduced biofilm formation and concomitantly with repressed rhamnolipid gene expression, only trace amount of extracellular rhamnolipids were detected. The QSIs did not completely inhibit virulence factor expression and production but their administration significantly lowered the virulence phenotypes at both the transcriptional and extracellular levels. This study shows the significant inhibitory effect of natural plant-derived compounds on the repression of QS systems in P. aeruginosa.

Rhamnolipid production was monitored for a period of 216 h using different substrates in Pseudomonas aeruginosa PAO1 and Burkholderia thailandensis E264 which showed comparable crude yields attained by both after 216 h. The crude yield for P. aeruginosa, however, was significantly higher at the early stages of fermentation (72 or 144 h). Additionally, P. aeruginosa produced rhamnolipid with odd and even carbon chain lipid moieties using odd carbon chain fatty acid substrates (up to 45.97 and 67.57%, respectively). In contrast, B. thailandensis produced rhamnolipid with predominantly even carbon chain lipid moieties (up to 99.26). These results indicate the use of the fatty acid synthesis (FAS II) pathway as the main source of lipid precursors in rhamnolipid biosynthesis by B. thailandensis. Isotope tracing using 0.25% stearic acid - d 35 + 1% glycerol as carbon substrate showed a single pattern of deuterium incorporation: with predominantly less than 15 deuterium atoms incorporated into a single Di-C 14 -C 14 rhamnolipid molecule. This further indicates that the FAS II pathway is the main source of the lipid precursor in rhamnolipid biosynthesis by B. thailandensis. The pathogenicity of these strains was also assessed, and results showed that B. thailandensis is significantly less pathogenic than P. aeruginosa with an LC50 at 24 h > 2500, approximately three logs higher than P. aeruginosa using the Galleria mellonella larva model.

Microbially produced rhamnolipids have significant commercial potential; however, the main bacterial producer, Pseudomonas aeruginosa, is an opportunistic human pathogen, which limits biotechnological exploitation. The non-pathogenic species Burkholderia thailandensis produces rhamnolipids; however, yield is relatively low. The aim of this study was to determine whether rhamnolipid production could be increased in Burkholderia thailandensis through mutation of genes responsible for the synthesis of the storage material polyhydroxyalkanoate (PHA), thereby increasing cellular resources for the production of rhamnolipids. Potential PHA target genes were identified in B. thailandensis through comparison with known function genes in Pseudomonas aeruginosa. Multiple knockout strains for the phbA, phbB and phbC genes were obtained and their growth characteristics and rhamnolipid and PHA production determined. The wild-type strain and an rhamnolipid (RL)-deficient strain were used as controls. Three knockout strains (ΔphbA1, ΔphbB1 and ΔphbC1) with the best enhancement of rhamnolipid production were selected for detailed study. ΔphbB1 produced the highest level of purified RL (3.78 g l -1 ) compared to the wild-type strain (1.28 g l -1 ). In ΔphbB1, the proportion of mono-rhamnolipid was also increased compared to the wild-type strain. The production of PHA was reduced by at least 80% in all three phb mutant strains, although never completely eliminated. These results suggest that, in contrast to Pseudomonas aeruginosa, knockout of the PHA synthesis pathway in Burkholderia thailandensis could be used to increase rhamnolipid production. The evidence of residual PHA production in the phb mutant strains suggests B. thailandensis possesses a secondary unelucidated PHA synthesis pathway.

Due to their high anti-oxidant activity, phlorotannins represent potential natural alternatives to synthetic preservatives currently used within the food industry. However, their successful integration into food products requires research into their chemical integrity, particularly when selecting appropriate storage conditions. Subsequently, this study aims to investigate the stability of low molecular weight phlorotannin fractions from Fucus vesiculosus (L.). Powder and aqueous fractions were stored under five different conditions for 10weeks. Phlorotannin stability was determined using Q-ToF-MS and UPLC-TQD-MS/MS and a DPPH assay. After 10weeks of storage, fractions suspended in an aqueous matrix underwent oxidation when exposed to continuous atmospheric oxygen and thermal degradation when exposed to a constant temperature of 50°C, resulting in decreases in radical scavenging activity (p<0.001). Phlorotannins remained stable under all other storage conditions. This study highlights phlorotannins as highly stable polymers, under certain storage conditions, with an excellent capacity for scavenging radicals., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Adequate fertility combined with effective weed management is important in maximizing corn ( Zea mays L.) grain yield. Corn uptake of nitrogen (N) is dependent upon many factors including weed species and density and the rate and formulation of applied N fertilizer. Understanding interactions among corn, applied N, and weeds is important in developing management strategies. Field studies were conducted in North Carolina to compare corn and weed responses to urea ammonium nitrate (UAN), sulfur-coated urea (SCU), and composted poultry litter (CPL) when a mixture of Palmer amaranth ( Amaranthus palmeri S. Wats.) and large crabgrass ( Digitaria sanguinalis L.) was removed with herbicides at heights of 8 or 16 cm. These respective removal timings corresponded with 22 and 28 days after corn planting or V2 and V3 stages of growth, respectively. Differences in N content in above-ground biomass of corn were noted early in the season due to weed interference but did not translate into differences in corn grain yield. Interactions of N source and N rate were noted for corn grain yield but these factors did not interact with timing of weed control. These results underscore that timely implementation of control tactics regardless of N fertility management is important to protect corn grain yield.

Burkholderia thailandensis E264 is a rhamnolipid (RL)-producing gram-negative bacterium first isolated from the soils and stagnant waters of central and north-eastern Thailand. Growth of B. thailandensis E264 under two different incubation temperatures (25 and 30 °C) resulted in a significantly higher dry cell biomass production at 30 °C (7.71 g/l) than at 25 °C (4.75 g/l) after 264 h; however, incubation at the lower temperature resulted in consistently higher concentration of RL production throughout the growth period. After 264 h, the concentration of crude RL extract for the 25 °C culture was 2.79 g/l compared to 1.99 g/l for the 30 °C culture. Overall RL production concentration after 264 h was 0.258 g/g dry cell biomass (DCB) for the 30 °C culture compared to 0.587 g/g DCB for the 25 °C culture. Real-time PCR (qPCR) was also used to analyse expression of the RL biosynthesis genes throughout the incubation period at 25 °C showing that the expression of the rhlA, rhlB and rhlC genes is continuous. During the log and early stationary phases of growth, expression levels remain low and are increased upon entry to the late stationary phase. B. thailandensis E264 produces mostly di-RLs and the Di-RL C14-C14 in most abundance (41.88 %). Fermentations were also carried out in small-scale bioreactors (4 l working volume) under controlled conditions, and results showed that RL production was maintained. Our findings show that B. thailandensis E264 has excellent potential for industrial scale RL production.

Purpose: Palmaria palmata (P. Palmata) is reported to contain anti-inflammatory and antioxidant compounds albeit no study has investigated these effects in humans., Methods: A randomised parallel placebo-controlled human intervention study was carried out to investigate the effect of consuming P. Palmata (5 g/day) incorporated into a bread on serum markers of inflammation [C-reactive protein (CRP); cytokine analysis] with secondary analysis investigating changes in lipids (cholesterol, triglycerides), thyroid function [thyroid-stimulating hormone (TSH)] and antioxidant status ferric reducing antioxidant power. ANCOVA with baseline values as covariates, controlling for age, BMI, sex and smoking status, was used to compare differences between treatment groups over time . In vitro studies investigated the inflammatory activity of P. Palmata extracts (hot water, cold water and ethanol extract), protein extracts and associated protein hydrolysates using a Caco-2 inflammation cell model., Results: Consumption of P. Palmata-enriched bread significantly increased serum CRP (+16.1 %, P = 0.011), triglycerides (+31.9 %, P = 0.001) and TSH (+17.2 %, P = 0.017) when compared to the control group. In vitro evaluation of P. palmata extracts and protein hydrolysates identified a significant induction of IL-8 secretion by Caco-2 cells, and the hot water P. palmata extract was shown to increase adipocyte glycerol release (P < 0.05)., Conclusion: Evidence from this human study suggests that P. palmata stimulates inflammation, increases serum triglycerides and alters thyroid function; however, these changes are not likely to impact health as changes remained within the normal clinical range. The data from the in vitro study provided indications that IL-8 may contribute to the apparent immunostimulation noted in the human study.

Rhamnolipids (RLs) are synthesised as a complex mixture of congeners comprising either one or two molecules of rhamnose glycosidically linked to a dimer of 3-hydroxy fatty acids varying in chain length and degree of saturation. Currently, HPLC-MS/MS is the most precise and accurate method for RL determination, while accurate quantification is limited. In this study, a rapid ultra pressure liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the rapid and quantification of individual RL congeners. Increased RLs specificity was achieved using tandem mass spectrometry in multiple reaction monitoring (MRM) mode which was used to quantify RL isomer pairs such as Rha-Rha-C8-C10/Rha-Rha-C10-C8 which are difficult to resolve chromatographically. UPLC showed an 18-fold reduction in retention time for Rha-Rha-C10-C10 (1.07 min) and a 17-fold reduction for Rha-C10-C10 (1.36), the major rhamnolipids present, compared to HPLC, with a total run time less than 2.2 min. The results show that the linear range for the main RL congeners (Rha-C10-C10 and Rha-Rha-C10-C10) is 0.1 to 100 μg/mL. The LOD and LOQ for Rha-C10-C10 is 0.05 and 0.1 μg/mL and for Rha-Rha-C10-C10 is 0.1 and 0.5 μg/mL, respectively. The method was validated for linearity, intra- and inter-day precision and accuracy in accordance with FDA guidelines. The method was applied for the quantification of 14 individual RL congeners produced by Pseudomonas aeruginosa ST5 and comparison of RLs composition on four different carbon sources. Quantification of the individual congeners showed a conserved congener distribution irrespective of carbon source with a preferential selection for C10 β-hydroxyacids as the lipid component of RLs. The only statistically significant differences detected were between actual RL yields on the various carbon sources.

An autonomous underwater vehicle (Seaglider) has been used to estimate marine primary production (PP) using a combination of irradiance and fluorescence vertical profiles. This method provides estimates for depth-resolved and temporally evolving PP on fine spatial scales in the absence of ship-based calibrations. We describe techniques to correct for known issues associated with long autonomous deployments such as sensor calibration drift and fluorescence quenching. Comparisons were made between the Seaglider, stable isotope ((13)C), and satellite estimates of PP. The Seaglider-based PP estimates were comparable to both satellite estimates and stable isotope measurements.

We investigated 32 net primary productivity (NPP) models by assessing skills to reproduce integrated NPP in the Arctic Ocean. The models were provided with two sources each of surface chlorophyll- a concentration (chlorophyll), photosynthetically available radiation (PAR), sea surface temperature (SST), and mixed-layer depth (MLD). The models were most sensitive to uncertainties in surface chlorophyll, generally performing better with in situ chlorophyll than with satellite-derived values. They were much less sensitive to uncertainties in PAR, SST, and MLD, possibly due to relatively narrow ranges of input data and/or relatively little difference between input data sources. Regardless of type or complexity, most of the models were not able to fully reproduce the variability of in situ NPP, whereas some of them exhibited almost no bias (i.e., reproduced the mean of in situ NPP). The models performed relatively well in low-productivity seasons as well as in sea ice-covered/deep-water regions. Depth-resolved models correlated more with in situ NPP than other model types, but had a greater tendency to overestimate mean NPP whereas absorption-based models exhibited the lowest bias associated with weaker correlation. The models performed better when a subsurface chlorophyll- a maximum (SCM) was absent. As a group, the models overestimated mean NPP, however this was partly offset by some models underestimating NPP when a SCM was present. Our study suggests that NPP models need to be carefully tuned for the Arctic Ocean because most of the models performing relatively well were those that used Arctic-relevant parameters.

The effects of fat substitution (≤ 15%) with commercial encapsulated and unencapsulated fish oils on the technological and eating quality of beef burgers over storage [modified atmosphere packs (80% O2:20% CO2); constantly illuminated retail display at 4 °C; for 15 days] were studied using design of experiment (DOE). Burger formulations comprised beef shin (59.5%), salt (0.5%), vitamin E (0.015%) combined with varying levels of beef-fat/fish oils depending on the treatment. Increasing amounts of encapsulated and unencapsulated fish oils in burgers increased polyunsaturated fatty acid content (P < 0.001). Storage decreased (P < 0.001) a* values, which was in agreement with oxymyoglobin data. Vitamin E inclusion in burgers resulted in higher (P < 0.01) oxymyoglobin values. TBARS values increased (P < 0.001) over storage as expected. Fat substitution with unencapsulated oils increased cook loss (P < 0.001) and decreased hardness (P < 0.05) compared to other treatments. Optimisation predicted a burger formulation with 7.8% substitution in beef-fat with encapsulated fish oil. Panellists scored the optimised burger formulation (P < 0.05) lower than controls for overall acceptability., (Copyright © 2015. Published by Elsevier Ltd.)

Plant extracts have traditionally been used as sources of natural antimicrobial compounds, although in many cases, the compounds responsible for their antimicrobial efficacy have not been identified. In this study, crude and dialysed extracts from dandelion root (Taraxacum officinale) were evaluated for their antimicrobial properties against Gram positive and Gram negative bacterial strains. The methanol hydrophobic crude extract (DRE3) demonstrated the strongest inhibition of microbial growth against Staphylococcus aureus, methicillin-resistant S. aureus and Bacillus cereus strains. Normal phase (NP) fractionation of DRE3 resulted in two fractions (NPF4 and NPF5) with enhanced antimicrobial activity. Further NP fractionation of NPF4 resulted in two fractions (NPF403 and NPF406) with increased antimicrobial activity. Further isolation and characterisation of compounds in NPF406 using liquid chromatography solid phase extraction nuclear magnetic resonance LC-SPE-NMR resulted in the identification of 9-hydroxyoctadecatrienoic acid and 9-hydroxyoctadecadienoic acid, while the phenolic compounds vanillin, coniferaldehyde and p-methoxyphenylglyoxylic acid were also identified respectively. The molecular mass of these compounds was confirmed by LC mass spectroscopy (MS)/MS. In summary, the antimicrobial efficacy of dandelion root extracts demonstrated in this study support the use of dandelion root as a source of natural antimicrobial compounds., (Copyright © 2015 John Wiley & Sons, Ltd.)

The objective of this study was to investigate the effect of key extraction parameters of extraction time (5-25 min), acid concentration (0-0.06 M HCl) and ultrasound amplitude (22.8-114 μm) on yields of bioactive compounds (total phenolics, fucose and uronic acid) from Ascophyllumnodosum. Response surface methodology was employed to optimize the extraction variables for bioactive compounds' yield. A second order polynomial model was fitted well to the extraction experimental data with (R(2)>0.79). Extraction yields of 143.12 mgGAE/gdb, 87.06 mg/gdb and 128.54 mg/gdb were obtained for total phenolics, fucose and uronic acid respectively at optimized extraction conditions of extraction time (25 min), acid concentration (0.03 M HCl) and ultrasonic amplitude (114 μm). Mass spectroscopy analysis of extracts show that ultrasound enhances the extraction of high molecular weight phenolic compounds from A. nodosum. This study demonstrates that ultrasound assisted extraction (UAE) can be employed to enhance extraction of bioactive compounds from seaweed., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Mushrooms and mushroom extracts have traditionally been used as therapies for a wide variety of ailments, including allergy, arthritis, and other inflammatory disorders. However, more evidence is required on the mechanism by which mushrooms exert these effects. In the present study, the anti-inflammatory properties of ethanol and hot water extracts prepared from 27 fungal samples collected between October and November 2011 at various forest locations in the southwest of Ireland were investigated using the lipopolysaccharide (LPS)-stimulated mouse macrophage (RAW264.7 cells) model of inflammation. LPS-stimulated cells were incubated in the presence of mushroom extracts at nontoxic concentrations for 24 h and the production of interleukin-6 (IL-6) was quantified by ELISA. Seven ethanolic and one hot water extract that decreased IL-6 production were selected for further study. The extracts were then incubated with LPS-stimulated cells for 24 h and the production of IL-6, tumor necrosis factor-alpha (TNF-α), and nitric oxide (NO) was measured. Ethanolic extracts prepared from Russula mairei, Lactarius blennius, Craterellus tubaeformis, Russula fellea, and Craterellus cornucopioides demonstrated selective anti-inflammatory activity by decreasing the production of NO and IL-6 but not TNF-α in LPS-stimulated RAW264.7 cells. These findings support existing evidence of the anti-inflammatory potential of mushroom extracts.

Phlorotannins are a group of complex polymers of phloroglucinol (1,3,5-trihydroxybenzene) unique to macroalgae. These phenolic compounds are integral structural components of the cell wall in brown algae, but also play many secondary ecological roles such as protection from UV radiation and defense against grazing. This study employed Ultra Performance Liquid Chromatography (UPLC) with tandem mass spectrometry to investigate isomeric complexity and observed differences in phlorotannins derived from macroalgae harvested off the Irish coast (Fucus serratus, Fucus vesiculosus, Himanthalia elongata and Cystoseira nodicaulis). Antioxidant activity and total phenolic content assays were used as an index for producing phlorotannin fractions, enriched using molecular weight cut-off dialysis with subsequent flash chromatography to profile phlorotannin isomers in these macroalgae. These fractions were profiled using UPLC-MS with multiple reaction monitoring (MRM) and the level of isomerization for specific molecular weight phlorotannins between 3 and 16 monomers were determined. The majority of the low molecular weight (LMW) phlorotannins were found to have a molecular weight range equivalent to 4-12 monomers of phloroglucinol. The level of isomerization within the individual macroalgal species differed, resulting in substantially different numbers of phlorotannin isomers for particular molecular weights. F. vesiculosus had the highest number of isomers of 61 at one specific molecular mass, corresponding to 12 phloroglucinol units (PGUs). These results highlight the complex nature of these extracts and emphasize the challenges involved in structural elucidation of these compounds.

Stingless bees accumulate deposits of plant resins that are mixed with beeswax to produce propolis. Previous studies have reported anti-microbial constituents of stingless bee (Tetragonula carbonaria) propolis from East Australia, but several components remained to be characterized. In the search of natural products yet unreported for Australian propolis, four bee deposit-resins of T. carbonaria bees were analysed by gas and liquid chromatography mass spectrometry with accurate mass measurements. Ethanolic extracts of the deposit-resins were tested in vitro against Staphylococcus aureus ATCC 25983 and Pseudomonas aeruginosa ATCC 27853 by the agar diffusion method. Phloroglucinols, flavonoids and isoprenoids were identified in samples. The crude extracts showed strong anti-staphylococcal effects but were less active against the Gram-negative bacterium. The diagnostic data enabled the identification of markers that can be used for profiling other Australian propolis sources and to target the isolation of bioactive phloroglucinols in future studies against antibiotic resistant S. aureus strains., (Copyright © 2014 John Wiley & Sons, Ltd.)

In the last decade a large amount of research has been directed at targeting algal resources for biologically active molecules. High-throughput in vitro antioxidant assays are routinely used to screen for biologically active compounds present in algal extracts when the requirement is to identify samples for progression to more detailed biological scrutiny. Whilst a myriad of antioxidant assays have been developed, this present chapter aims to give step-by-step practical guidance on how to carry out some of the most popular and biologically relevant assays at the bench.

Small endogenous vesicles called exosomes are beginning to be explored as drug delivery vehicles. The in vivo targets of exosomes are poorly understood; however, they are believed to be important in cell-to-cell communication and may play a prominent role in cancer metastasis. We aimed to elucidate whether cancer derived exosomes can be used as drug delivery vehicles that innately target tumors over normal tissue. Our in vitro results suggest that while there is some specificity towards cancer cells over "immortalized" cells, it is unclear if the difference is sufficient to achieve precise in vivo targeting. Additionally, we found that exosomes associate with their cellular targets to a significantly greater extent (>10-fold) than liposomes of a similar size. Studies on the association of liposomes mimicking the unique lipid content of exosomes revealed that the lipid composition contributes significantly to cellular adherence/internalization. Cleavage of exosome surface proteins yielded exosomes exhibiting reduced association with their cellular targets, demonstrating the importance of proteins in binding/internalization. Furthermore, although acidic conditions are known to augment the metastatic potential of tumors, we found that cells cultured at low pH released exosomes with significantly less potential for cellular association than cells cultured at physiological pH., (Published by Elsevier B.V.)

Antimicrobial properties of ethanol and water extracts from eight Asteraceae species were investigated against three Gram positive (Staphylococcus aureus, MRSA and Bacillus cereus) and two Gram negative (Escherichia coli and Salmonella typhimurium) bacterial strains. Ethanol extracts from Centaurea scabiosa, Arctium minus, Taraxacum officinale, Centaurea nigra and Cirsium palustre demonstrated antimicrobial activity against strains of S. aureus, MRSA and B. cereus (MIC=187.5-365μg/ml). Ethanol extracts also had higher antioxidant activities and phenolic content demonstrating a link between these compounds and the bioactivity of these extracts. Further investigation into the phenolic content of ethanol extracts using UPLC-MS/MS lead to the identification and quantification of numerous phenolic compounds in all species including; 18 from Cirsium arvense, 16 from Cirsium vulgare, 19 from C. palustre, 15 from C. nigra, 17 from C. scabiosa, 14 from Sonchus asper, 17 from A. minus and 11 from T. officinale., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Changes in the net heat flux (NHF) into the ocean have profound impacts on global climate. We analyse a long-term plankton time-series and show that the NHF is a critical indicator of ecosystem dynamics. We show that phytoplankton abundance and diversity patterns are tightly bounded by the switches between negative and positive NHF over an annual cycle. Zooplankton increase before the transition to positive NHF in the spring but are constrained by the negative NHF switch in autumn. By contrast bacterial diversity is decoupled from either NHF switch, but is inversely correlated (r = -0.920) with the magnitude of the NHF. We show that the NHF is a robust mechanistic tool for predicting climate change indicators such as spring phytoplankton bloom timing and length of the growing season.

Introduction: Several analytical methods exist for the determination of sulphoraphane or sulphoraphane nitrile from biological matrices and plant extracts. However, no UPLC-MS/MS method exists for the simultaneous detection of both., Objective: To develop and validate an UPLC-MS/MS method for the simultaneous analysis of sulphoraphane and sulphoraphane nitrile from Brassica oleracea L. ssp. italica, Methods: This method was developed utilising an Acquity BEH C8 column with gradient elution combined with tandem mass spectrometry, using positive electrospray ionisation in multiple reaction monitoring mode., Results: The retention times for sulphoraphane and sulphoraphane nitrile were 0.4 and 0.6 min respectively, and total run time was 3 min. The method was validated for linearity, sensitivity, precision, accuracy, matrix effects and recovery. The method was employed to determine glucoraphanin hydrolysis products in broccoli and the predominant product was found to vary depending on the variety tested. It was also applied to the accurate determination of sulphoraphane and sulphoraphane nitrile in broccoli samples hydrolysed under different conditions. It was observed that the formation of sulphoraphane and sulphoraphane nitrile was influenced by the temperature of the reaction., Conclusion: The validated UPLC-MS/MS method for simultaneous detection of sulphoraphane and sulphoraphane nitrile was shown to be applicable to broccoli plants and is expected to be applicable to other cruciferous sources., (Copyright © 2013 John Wiley & Sons, Ltd.)

The combination of hyphenated techniques, LC-SPE-NMR and LC-MS, to isolate and identify minor isomeric compounds from an ethyl acetate fraction of Taraxacum officinale root was employed in this study. Two distinct fractions of 4-hydroxyphenylacetic acid derivatives of inositol were isolated and characterised by spectroscopic methods. The (1)H NMR spectra and MS data revealed two groups of compounds, one of which were derivatives of the di-4-hydroxyphenylacetic acid derivative of the inositol compound tetrahydroxy-5-[2-(4-hydroxyphenyl)acetyl] oxycyclohexyl-2-(4-hydroxyphenyl) acetate, while the other group consisted of similar tri-substituted inositol derivatives. For both fractions the derivatives of inositols vary in the number of 4-hydroxyphenylacetic acid groups present and their position and geometry on the inositol ring. In total, three di-substituted and three tri-substituted 4-hydroxyphenylacetic acid inositol derivates were identified for the first time along with a further two previously reported di-substituted inositol derivatives., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Freeze-dried fenugreek (Trigonella foenum-graecum) seeds and bitter melon (Momordica charantia) fruit were extracted sequentially using non-polar to polar solvents, with further separation carried out on polar extracts by molecular weight cut off dialysis. The fenugreek ethyl acetate crude extract (FGE3) demonstrated the highest antioxidant activity, in terms of Trolox Equivalents (TE), for both the DPPH (35.338±0.908 mg TE/g) and FRAP (77.352±0.627 mg TE/g) assays. This extract also contained the highest phenolic content, in terms of Gallic Acid Equivalents (GAE) (106.316±0.377 mg GAE/g). Despite having considerably lower antioxidant activity than fenugreek, the highest antioxidant activities for bitter fruit were observed in the hexane (BME1) and methanol hydrophilic<3.5 kDa dialysed (BME4<3.5 kDa) extracts, while the highest phenolic content was found in the methanol hydrophilic>3.5 kDa (BME4>3.5 kDa) dialysed extract. UPLC-MS was used to quantify 18 phenolic compounds from fenugreek and 13 from bitter melon in active crude extracts. The flavonoids apigenin-7-O-glycoside (1955.55 ng/mg) and luteolin-7-O-glycoside (725.50 ng/mg) were the most abundant compounds in FGE3, while bitter melon extracts contained only small amounts of mainly phenolic acids. A further 5 fenugreek and 1 bitter melon compounds were identified in trace amounts from the same extracts, respectively., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

To date, numerous studies have reported on the antidiabetic properties of various plant extracts through inhibition of carbohydrate-hydrolysing enzymes. The objective of this research was to evaluate extracts of seaweeds for α-amylase and α-glucosidase inhibitory effects. Cold water and ethanol extracts of 15 seaweeds were initially screened and from this, five brown seaweed species were chosen. The cold water and ethanol extracts of Ascophyllum nodosum had the strongest α-amylase inhibitory effect with IC50 values of 53.6 and 44.7 μg/ml, respectively. Moreover, the extracts of Fucus vesiculosus Linnaeus were found to be potent inhibitors of α-glucosidase with IC50 values of 0.32 and 0.49 μg/ml. The observed effects were associated with the phenolic content and antioxidant activity of the extracts, and the concentrations used were below cytotoxic levels. Overall, our findings suggest that brown seaweed extracts may limit the release of simple sugars from the gut and thereby alleviate postprandial hyperglycaemia., (Copyright © 2013. Published by Elsevier Ltd.)

An efficient, food-friendly process for the enrichment of macroalgal phlorotannins from solid-liquid extracts (SLE) of three brown macroalgae, namely Fucus spiralis Linnaeus, Pelvetia canaliculata (Linnaeus) Decaisne & Thuret and Ascophyllum nodosum (Linnaeus) Le Jolis, has been demonstrated. The initial utilisation of molecular weight cut-off (MWCO) dialysis generated fractions of low molecular weight (LMW) (<3.5 kDa) and of high molecular weight (HMW) (3.5-100 kDa and >100 kDa) from cold water, hot water and aqueous ethanolic SLE extracts. An enhancement of the total phenolic content (TPC), radical scavenging abilities (RSA) and ferric reducing antioxidant power (FRAP) in the HMW fractions of 3.5-100 kDa and/or >100 kDa from the cold water and aqueous ethanolic extracts was observed. The initial weak TPC, RSA and FRAP observed in the LMW fractions relative to the HMW fractions were substantially enhanced following a reverse-phase flash chromatography fractionation method. Quadrupole time-of-flight mass spectrometry (Q-Tof-MS) suggests that phlorotannins of varying degrees of phloroglucinol polymerisation are present in LMW fractions of the three brown macroalgal species. The development of a food-friendly process for the extraction and enrichment of phlorotannins from Irish macroalgae is vital to facilitate the use of this valuable resource in future developments of macroalgal-based functional foods., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

A range of isolates of Pseudomonas aeruginosa from widely different environmental sources were examined for their ability to synthesise rhamnolipid biosurfactants. No significant differences in the quantity or composition of the rhamnolipid congeners could be produced by manipulating the growth conditions. Sequences for the rhamnolipid genes indicated low levels of strain variation, and the majority of polymorphisms did lead to amino acid sequence changes that had no evident phenotypic effect. Expression of the rhlB and rhlC rhamnosyltransferase genes showed a fixed sequential expression pattern during growth, and no significant up-regulation could be induced by varying producer strains or growth media. The results indicated that rhamnolipids are highly conserved molecules and that their gene expression has a rather stringent control. This leaves little opportunity to manipulate and greatly increase the yield of rhamnolipids from strains of P. aeruginosa for biotechnological applications.

Ocean color measured from satellites provides daily, global estimates of marine inherent optical properties (IOPs). Semi-analytical algorithms (SAAs) provide one mechanism for inverting the color of the water observed by the satellite into IOPs. While numerous SAAs exist, most are similarly constructed and few are appropriately parameterized for all water masses for all seasons. To initiate community-wide discussion of these limitations, NASA organized two workshops that deconstructed SAAs to identify similarities and uniqueness and to progress toward consensus on a unified SAA. This effort resulted in the development of the generalized IOP (GIOP) model software that allows for the construction of different SAAs at runtime by selection from an assortment of model parameterizations. As such, GIOP permits isolation and evaluation of specific modeling assumptions, construction of SAAs, development of regionally tuned SAAs, and execution of ensemble inversion modeling. Working groups associated with the workshops proposed a preliminary default configuration for GIOP (GIOP-DC), with alternative model parameterizations and features defined for subsequent evaluation. In this paper, we: (1) describe the theoretical basis of GIOP; (2) present GIOP-DC and verify its comparable performance to other popular SAAs using both in situ and synthetic data sets; and, (3) quantify the sensitivities of their output to their parameterization. We use the latter to develop a hierarchical sensitivity of SAAs to various model parameterizations, to identify components of SAAs that merit focus in future research, and to provide material for discussion on algorithm uncertainties and future emsemble applications.

The impact of Ca(2+) counterions on the adsorption at the air-water interface and self-assembly in aqueous solution of the rhamnolipid biosurfactant and its mixture with the anionic surfactant sodium dodecylbenzenesulfonate, LAS, has been studied using neutron reflectometry and small-angle neutron scattering. The results illustrate how rhamnolipids are calcium tolerant and how their blending with conventional anionic surfactants improves the calcium tolerance of the anionic surfactant. Ca(2+) has relatively little effect upon the adsorption and self-assembly of the monorhamnose, R1, and dirhamnose, R2, rhamnolipids, even at high pH, due to their predominantly nonionic nature. For R1/R2 mixtures the addition of Ca(2+) has little impact upon the adsorbed amount or the surface composition. For R2/LAS mixtures the addition of Ca(2+) results in an increased adsorption and a surface slightly richer in R2. The weak binding of Ca(2+) to R1 and R2 does result in a change to the degree of ionization of the micelles and especially for mixed R1/R2 micelles at R1-rich solution compositions. The stronger binding of Ca(2+) to LAS results in the addition of Ca(2+) having a much greater impact on the self-assembly of R1/LAS and R2/LAS mixtures. For R1/LAS mixtures the addition of Ca(2+) promotes the formation of more planar structures, even at low surfactant concentrations where in the absence of Ca(2+) mixed globular micelle formation dominates. In R2/LAS mixtures, where there is a greater contrast between the high and low preferred curvatures associated with R2 and LAS, the addition of Ca(2+) results in a more complex evolution in micellar aggregation and the degree of ionization of the micelles. This results in variations in Ca(2+) binding that promotes micellar structures in which a spatial segregation of the two surfactant components within the micelle occurs.

The composition and abundance of mycosporine-like amino acids (MAAs) were investigated in the surface waters along a 13,000-km meridional transect (52° N to 45° S) in the Atlantic Ocean (Atlantic Meridional Transect programme: Cruise AMT 18: 4/10/2008-10/11/2008). MAAs were ubiquitous along the transect, although the composition of the MAAs was variable. Highest concentrations were in the far south (below 40° S; MAA >1 μg L(-1)) and in north subtropical equatorial region (NER: 0-25° N; MAA up to 0.8 μg L(-1)). Highest MAA relative to chlorophyll-a occurred in the NER (MAA/chl-a ratio between 2 and 5). MAA/chl-a significantly correlated with the preceding month's mean daily UV dose and with UV-B/UV-A. In the far south, high MAA concentrations coincided with high phytoplankton biomass, high nutrients and a deep mixed layer associated with the austral spring. Here, the phytoplankton community was dominated by micro- and nano-eukaryotes. At the NER, the high MAA/chl-a coincided with low nutrient concentrations, a shallow mixed layer depth (20-70 m) and to a lesser extent to a shallow nitracline (40-90 m). Here, the phytoplankton consisted primarily of picophytoplankton (0-0.2 μm), dominated by the pico-cyanobacteria Synechococcus sp. and Prochlorococcus sp. and by the nitrogen fixing filamentous cyanobacterium Trichodesmium. The low nitrate concentrations (<0.1 μmol L(-1)) at the NER suggest that nitrogen fixation was required for MAA production. Specific MAAs could not easily be assigned to particular groups of phytoplankton and we could not rule out the possibility that MAAs were associated with symbiotic cyanobacteria contained within heterotrophic dinoflagellates or diatoms.

The aims of this work were the characterisation and the evaluation of potential environmental applications of the bioemulsifiers produced by Variovorax paradoxus 7bCT5. V. paradoxus 7bCT5 produces a mixture of high molecular weight polysaccharides. The extracellular bioemulsifiers were able to produce a thick stable oil/water emulsion and maintained the emulsification activity after boiling and at low temperatures. Environmental behavior and impact of bioemulsifiers release were assessed by evaluating biodegradability, toxicity and soil sorption. Respirometric tests showed that moderate biodegradability occurred by soil bacterial inoculum. Furthermore, the produced compounds did not show any toxic properties through different ecotoxicological tests. The K(d) values ranged from 1.3 to 7.3 L/kg indicating a high sorption affinity of the bioemulsifier molecules to soil particles. The soil sorption affinity likely affected the bioemulsifier ability to remove hydrocarbons from contaminated soils. In fact, V. paradoxus 7bCT5 bioemulsifiers significantly increased the removal of crude-oil from sandy soil compared to water., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The ethyl acetate extracts of the bark and leaves of Ficus coronata were separated by column chromatography and the resulting fractions tested for their bioactivity toward methicillin-resistant-Staphylococcus aureus (MRSA) and M. luteus. The bioactive column chromatography fractions were further separated by preparative thin layer chromatography (TLC) and the resulting bands investigated by high-performance liquid chromatography-electrospray ionization-ion trap mass spectrometry (HPLC-ESI-MS(n) ) and ESI-MS(n) . The resulting retention times, molecular masses, their fragmentation patterns, and the chemnet database (www.chemnetbase.com) were then used in the dereplication process by structural elucidation of some of the compounds when compared with known structures of natural origin. Some molecular masses and the corresponding fragmentations were found that did not correlate with any known compounds thus revealing potentially novel natural products that could be investigated on a larger scale and could ultimately find application as new drugs against MRSA and other multidrug-resistant microorganisms. Structures are also proposed for known compounds that have not been previously reported for F. coronata., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Particle-mediated epidermal delivery (PMED) of small quantities of DNA (0.5-4.0 μg) has been reported to both induce an immune response and protect against disease in human subjects. In order for the PMED of DNA to be a viable technique for vaccination, the adsorbed DNA must be stable during shipping and storage. Here, we report that the storage stability of plasmid DNA adsorbed to 2-μm gold particles is strongly dependent on sample water content. Gold/DNA samples stored at 60°C and 6% relative humidity (RH) maintained supercoil content after 4-month storage, whereas storage at higher RHs facilitated degradation. Storage with desiccants had stabilizing effects on DNA similar to storage at 6% RH. However, storage with "indicating" Drierite and phosphorus pentoxide resulted in enhanced rates of DNA degradation., (Copyright © 2011 Wiley-Liss, Inc.)