In vitro batch cultures of gut microbiota from healthy and ulcerative colitis (UC) subjects suggest that sulphate-reducing bacteria levels are raised in UC and by a protein-rich diet.

Imbalances in gut microbiota composition during ulcerative colitis (UC) indicate a role for the microbiota in propagating the disorder. Such effects were investigated using in vitro batch cultures (with/without mucin, peptone or starch) inoculated with faecal slurries from healthy or UC patients; the growth of five bacterial groups was monitored along with short-chain fatty acid (SCFA) production. Healthy cultures gave two-fold higher growth and SCFA levels with up to ten-fold higher butyrate production. Starch gave the highest growth and SCFA production (particularly butyrate), indicating starch-enhanced saccharolytic activity. Sulphate-reducing bacteria (SRB) were the predominant bacterial group (of five examined) for UC inocula whereas they were the minority group for the healthy inocula. Furthermore, SRB growth was stimulated by peptone presumably due to the presence of sulphur-rich amino acids. The results suggest raised SRB levels in UC, which could contribute to the condition through release of toxic sulphide.

Selection of potential probiotic lactic acid bacteria from fermented olives by in vitro tests

The present study aims to evaluate the probiotic potential of lactic acid bacteria (LAB) isolated from naturally fermented olives and select candidates to be used as probiotic starters for the improvement of the traditional fermentation process and the production of newly added value functional foods. Seventy one (71) lactic acid bacterial strains (17 Leuconostoc mesenteroides, 1 Ln. pseudomesenteroides, 13 Lactobacillus plantarum, 37 Lb. pentosus, 1 Lb. paraplantarum, and 2 Lb. paracasei subsp. paracasei) isolated from table olives were screened for their probiotic potential. Lb. rhamnosus GG and Lb. casei Shirota were used as reference strains. The in vitro tests included survival in simulated gastrointestinal tract conditions, antimicrobial activity (against Listeria monocytogenes, Salmonella Enteritidis, Escherichia coli O157:H7), Caco-2 surface adhesion, resistance to 9 antibiotics and haemolytic activity. Three (3) Lb. pentosus, 4 Lb. plantarum and 2 Lb. paracasei subsp. paracasei strains demonstrated the highest final population (>8 log cfu/ml) after 3 h of exposure at low pH. The majority of the tested strains were resistant to bile salts even after 4 h of exposure, while 5 Lb. plantarum and 7 Lb. pentosus strains exhibited partial bile salt hydrolase activity. None of the strains inhibited the growth of the pathogens tested. Variable efficiency to adhere to Caco-2 cells was observed. This was the same regarding strains' susceptibility towards different antibiotics. None of the strains exhibited β-haemolytic activity. As a whole, 4 strains of Lb. pentosus, 3 strains of Lb. plantarum and 2 strains of Lb. paracasei subsp. paracasei were found to possess desirable in vitro probiotic properties similar to or even better than the reference probiotic strains Lb. casei Shirota and Lb. rhamnosus GG. These strains are good candidates for further investigation both with in vivo studies to elucidate their potential health benefits and in olive fermentation processes to assess their technological performance as novel probiotic starters.

The neolithisation of Liguria (NW Italy): an environmental archaeological and palaeoenvironmental perspective

The archaeological evidence compiled for Liguria has enabled the formulation of a comprehensive model of Neolithic social, technological and economic development (∼7800–5700 cal yrs BP). The model indicates that during the Early and Middle Neolithic (∼7800–6300 cal yrs BP; ‘Impressed Ware’ and ‘Square Mouthed’ pottery cultures) human activity mainly focussed on low (coastal) and mid-altitude areas. By the Late Neolithic (∼6300–5700 cal yrs BP; ‘Chassey’ culture) farming practices were taking place over a wider range of altitudes and involved transhumant pastoralism. Complementary environmental archaeological and palaeoecological records from caves, open-air sites, lakes and mires indicate that human activities had a more significant impact on the environment than previously thought. This included clearance, especially Abies, Ulmus, Fraxinus and Tilia, and woodland utilisation and management (e.g. leaf foddering), as well as cereal cultivation and animal husbandry. The influence of Middle Holocene climatic changes, especially from ∼7800 cal yrs BP, on the direction of vegetation changes and socio-economic developments during the Neolithic remain uncertain.

Assessment of plant uptake models used in exposure assessment tools for soils contaminated with organic pollutants

The aim of this study was to evaluate and improve the accuracy of plant uptake models for neutral hydrophobic organic pollutants (1 < logKOW < 9, −8 < logKAW < 0) used in regulatory exposure assessment tools, using uncertainty and sensitivity analyses. The models considered were RAIDAR, EUSES, CSOIL, CLEA, and CalTOX. In this research, CSOIL demonstrated the best performance of all five exposure assessment tools for root uptake from polluted soil in comparison with observed data, but no model predicted shoot uptake well. Recalibration of the transpiration and volatilisation parameters improved the performance of CSOIL and CLEA. The dominant pathway for shoot uptake simulated differed according to the properties of the chemical under consideration; those with a higher air–water partition coefficient were transported into shoots via the soil-air-plant pathway, while chemicals with a lower octanol–water partition coefficient and air–water partition coefficient were transported via the root. The soil organic carbon content was a particularly sensitive parameter in each model and using a site specific value improved model performance.

In vitro evaluation of the fermentation properties and potential probiotic activity of Lactobacillus plantarum C4 in batch culture systems

Lactobacillus plantarum C4 has been tested in in vitro pH-controlled anaerobic faecal batch cultures as compared to Lactobacillus rhamnosus GG to determine changes caused to the composition of faecal bacteria. Effects upon major groups of the microbiota and levels of short-chain fatty acids (SCFA) were assessed over 24 h. Concomitantly, hydrophobic character and ability of both bacterial cells to adhere in vitro to Caco-2 cells were investigated. Quantitative analysis of bacterial populations revealed that there was a significant increase in Lactobacillus/Enterococcus numbers in vessels with probiotic supplemented with fructooligosaccharides (FOS), compared to the negative control. L. plantarum C4 showed to have more hydrophilic behaviour and fulfilled better adhesive properties, compared to L. rhamnosus GG. Thus, L. plantarum C4 can modulate the intestinal microbiota in vitro, promoting changes in some numerically and metabolically relevant microbial populations and shifts in the production of SCFA.

A palaeoenvironmental context for terminal upper Palaeolithic and Mesolithic activity in the Colne Valley: offsite records contemporary with occupation at three ways Wharf, Uxbridge

Multi-proxy analyses from floodplain deposits in the Colne Valley, southern England, have provided a palaeoenvironmental context for the immediately adjacent Terminal Upper Palaeolithic and Early Mesolithic site of Three Ways Wharf. These deposits show the transition from an open cool environment to fully developed heterogeneous floodplain vegetation during the Early Mesolithic. Several distinct phases of burning are shown to have occurred that are chronologically contemporary with the local archaeological record. The floodplain itself is shown to have supported a number of rare Urwaldrelikt insect species implying human manipulation of the floodplain at this time must have been limited or episodic. By the Late Mesolithic a reed-sedge swamp had developed across much of the floodplain, within which repeated burning of the in situ vegetation took place. This indicates deliberate land management practices utilising fire, comparable with findings from other floodplain sequences in southern Britain. With similar sedimentary sequences known to exist across the Colne Valley, often closely associated with contemporary archaeology, the potential for placing the archaeological record within a spatially explicit palaeoenvironmental context is great.

The polychaete worm Nereis diversicolor increases mercury lability and methylation in intertidal mudflats

The polychaete worm Nereis diversicolor engineers its environment by creating oxygenated burrows in anoxic intertidal sediments. The authors carried out a laboratory microcosm experiment to test the impact of polychaete burrowing and feeding activity on the lability and methylation of mercury in sediments from the Bay of Fundy, Canada. The concentration of labile inorganic mercury and methylmercury in burrow walls was elevated compared to worm-free sediments. Mucus secretions and organic detritus in worm burrows increased labile mercury concentrations. Worms decreased sulfide concentrations, which increased Hg bioavailability to sulfate-reducing bacteria and increased methylmercury concentrations in burrow linings. Because the walls of polychaete burrows have a greater interaction with organisms, and the overlying water, the concentrations of mercury and methylmercury they contain is more toxicologically relevant to the base of a coastal food web than bulk samples. The authors recommend that researchers examining Hg in marine environments account for sediment dwelling invertebrate activity to more fully assess mercury bioavailability.

Moisture can be the dominant environmental parameter governing cadaver decomposition in soil

Forensic taphonomy involves the use of decomposition to estimate postmortem interval (PMI) or locate clandestine graves. Yet, cadaver decomposition remains poorly understood, particularly following burial in soil. Presently, we do not know how most edaphic and environmental parameters, including soil moisture, influence the breakdown of cadavers following burial and alter the processes that are used to estimate PMI and locate clandestine graves. To address this, we buried juvenile rat (Rattus rattus) cadavers (∼18 g wet weight) in three contrasting soils from tropical savanna ecosystems located in Pallarenda (sand), Wambiana (medium clay), or Yabulu (loamy sand), Queensland, Australia. These soils were sieved (2 mm), weighed (500 g dry weight), calibrated to a matric potential of -0.01 megapascals (MPa), -0.05 MPa, or -0.3 MPa (wettest to driest) and incubated at 22 °C. Measurements of cadaver decomposition included cadaver mass loss, carbon dioxide-carbon (CO2-C) evolution, microbial biomass carbon (MBC), protease activity, phosphodiesterase activity, ninhydrin-reactive nitrogen (NRN) and soil pH. Cadaver burial resulted in a significant increase in CO2-C evolution, MBC, enzyme activities, NRN and soil pH. Cadaver decomposition in loamy sand and sandy soil was greater at lower matric potentials (wetter soil). However, optimal matric potential for cadaver decomposition in medium clay was exceeded, which resulted in a slower rate of cadaver decomposition in the wettest soil. Slower cadaver decomposition was also observed at high matric potential (-0.3 MPa). Furthermore, wet sandy soil was associated with greater cadaver decomposition than wet fine-textured soil. We conclude that gravesoil moisture content can modify the relationship between temperature and cadaver decomposition and that soil microorganisms can play a significant role in cadaver breakdown. We also conclude that soil NRN is a more reliable indicator of gravesoil than soil pH.

A methodology to measure the environmental impact of ICT operating systems across different device platforms

Abstract: A new methodology was created to measure the energy consumption and related green house gas (GHG) emissions of a computer operating system (OS) across different device platforms. The methodology involved the direct power measurement of devices under different activity states. In order to include all aspects of an OS, the methodology included measurements in various OS modes, whilst uniquely, also incorporating measurements when running an array of defined software activities, so as to include OS application management features. The methodology was demonstrated on a laptop and phone that could each run multiple OSs, results confirmed that OS can significantly impact the energy consumption of devices. In particular, the new versions of the Microsoft Windows OS were tested and highlighted significant differences between the OS versions on the same hardware. The developed methodology could enable a greater awareness of energy consumption, during both the software development and software marketing processes.

New insights into the impact of Lactobacillus population on host-bacteria metabolic interplay

We aimed at evaluating the association between intestinal Lactobacillus sp. composition and their metabolic activity with the host metabolism in adult and elderly individuals. Faecal and plasma metabolites were measured and correlated to the Lactobacillus species distribution in healthy Estonian cohorts of adult (n=16; <48 y) and elderly (n=33; >65 y). Total cholesterol, LDL, C-reactive protein and glycated hemoglobin were statistically higher in elderly, while platelets, white blood cells and urinary creatinine were higher in adults. Aging was associated with the presence of L. paracasei and L. plantarum and the absence of L. salivarius and L. helveticus. High levels of intestinal Lactobacillus sp. were positively associated with increased concentrations of faecal short chain fatty acids, lactate and essential amino acids. In adults, high red blood cell distribution width was positively associated with presence of L. helveticus and absence of L. ruminis. L. helveticus was correlated to lactate and butyrate in faecal waters. This indicates a strong relationship between the composition of the gut Lactobacillus sp. and host metabolism. Our results confirm that aging is associated with modulations of blood biomarkers and intestinal Lactobacillus species composition. We identified specific Lactobacillus contributions to gut metabolic environment and related those to blood biomarkers. Such associations may prove useful to decipher the biological mechanisms underlying host-gut microbial metabolic interactions in an ageing population.

Effects of coastal managed retreat on mercury biogeochemistry

We investigated the impact of managed retreat on mercury (Hg) biogeochemistry at a site subject to diffuse contamination with Hg. We collected sediment cores from an area of land behind a dyke one year before and one year after it was intentionally breached. These sediments were compared to those of an adjacent mudflat and a salt marsh. The concentration of total mercury (THg) in the sediment doubled after the dyke was breached due to the deposition of fresh sediment that had a smaller particle size, and higher pH. The concentration of methylmercury (MeHg) was 27% lower in the sediments after the dyke was breached. We conclude that coastal flooding during managed retreat of coastal flood defences at this site has not increased the risk of Hg methylation or bioavailability during the first year. As the sediment becomes vegetated, increased activity of Hg-methylating bacteria may accelerate Hg-methylation rate.

Late Würm and Early-Middle Holocene environmental change and human activities in the Northern Apennines, Italy

An enhanced radiocarbon-dated pollen-stratigraphical record from Rovegno (Liguria, 812m asl), northern Apennines (Italy), has provided a history of vegetation succession from before 17,056-16,621 cal yrs BP to the present day. The record indicates the transition from open Pinus woodland to Artemisia dominated grassland, and finally Juniperus shrubland during the late Würm. This is succeeded by Betula and Pinus woodland, and the expansion of thermophilous taxa, namely Abies, Corylus and Quercus during the Late Würm Lateglacial Interstadial. The ‘Younger Dryas’ is possibly represented by an increase in Betula and Artemisia. During the early Holocene, mixed coniferous-deciduous woodland is dominant with Quercus, as well as Abies, Fagus and Corylus. Fagus woodland becomes established sometime before 6488-6318 cal yrs BP, but never becomes a major component of the woodland cover. Throughout the middle Holocene, Abies woodland fl uctuates, with marked declines between 6488-6318 cal yrs BP and 5287-4835 cal yrs BP, although the cause remains uncertain. Finally, the paper evaluates the application of non-pollen palynomorphs, especially coprophilous fungal spores, at Prato Spilla ‘A’ (Emilia Romagna) and concludes that greater caution must be used when interpreting middle Holocene human activity based upon pollen data alone

Modelling the bioaccumulation of persistent organic pollutants in agricultural food chains for regulatory exposure assessment

New models for estimating bioaccumulation of persistent organic pollutants in the agricultural food chain were developed using recent improvements to plant uptake and cattle transfer models. One model named AgriSim was based on K OW regressions of bioaccumulation in plants and cattle, while the other was a steady-state mechanistic model, AgriCom. The two developed models and European Union System for the Evaluation of Substances (EUSES), as a benchmark, were applied to four reported food chain (soil/air-grass-cow-milk) scenarios to evaluate the performance of each model simulation against the observed data. The four scenarios considered were as follows: (1) polluted soil and air, (2) polluted soil, (3) highly polluted soil surface and polluted subsurface and (4) polluted soil and air at different mountain elevations. AgriCom reproduced observed milk bioaccumulation well for all four scenarios, as did AgriSim for scenarios 1 and 2, but EUSES only did this for scenario 1. The main causes of the deviation for EUSES and AgriSim were the lack of the soil-air-plant pathway and the ambient air-plant pathway, respectively. Based on the results, it is recommended that soil-air-plant and ambient air-plant pathway should be calculated separately and the K OW regression of transfer factor to milk used in EUSES be avoided. AgriCom satisfied the recommendations that led to the low residual errors between the simulated and the observed bioaccumulation in agricultural food chain for the four scenarios considered. It is therefore recommended that this model should be incorporated into regulatory exposure assessment tools. The model uncertainty of the three models should be noted since the simulated concentration in milk from 5th to 95th percentile of the uncertainty analysis often varied over two orders of magnitude. Using a measured value of soil organic carbon content was effective to reduce this uncertainty by one order of magnitude.

The impact of the abrupt 8.2 ka cold event on the Mesolithic population of western Scotland: a Bayesian chronological analysis using ‘activity events’ as a population proxy

The potential impact of the abrupt 8.2 ka cold event on human demography, settlement patterns and culture in Europe and the Near East has emerged as a key theme in current discussion and debate. We test whether this event had an impact on the Mesolithic population of western Scotland, a case study located within the North Atlantic region where the environmental impact of the 8.2 ka event is likely to have been the most severe. By undertaking a Bayesian analysis of the radiocarbon record and using the number of activity events as a proxy for the size of the human population, we find evidence for a dramatic reduction in the Mesolithic population synchronous with the 8.2 ka event. We interpret this as reflecting the demographic collapse of a low density population that lacked the capability to adapt to the rapid onset of new environmental conditions. This impact of the 8.2 ka event in the North Atlantic region lends credence to the possibility of a similar impact on populations in Continental Europe and the Near East.