Integrating microalgae production with anaerobic digestion: a biorefinery approach

This is the peer reviewed version of the following article: [Uggetti, E. , Sialve, B. , Trably, E. and Steyer, J. (2014), Integrating microalgae production with anaerobic digestion: a biorefinery approach. Biofuels, Bioprod. Bioref, 8: 516-529. doi:10.1002/bbb.1469], which has been published in final form at https://doi.org/10.1002/bbb.1469. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingIn the energy and chemical sectors, alternative production chains should be considered in order to simultaneously reduce the dependence on oil and mitigate climate change. Biomass is probably the only viable alternative to fossil resources for production of liquid transportation fuels and chemicals since, besides fossils, it is one of the only available sources of carbon-rich material on Earth. Over recent years, interest in microalgae biomass has grown in both fundamental and applied research fields. The biorefinery concept includes different technologies able to convert biomass into added-value chemicals, products (food and feed) and biofuels (biodiesel, bioethanol, biohydrogen). As in oil refinery, a biorefinery aims at producing multiple products, maximizing the value derived from differences in biomass components, including microalgae. This paper provides an overview of the various microalgae-derived products, focusing on anaerobic digestion for conversion of microalgal biomass into methane. Special attention is paid to the range of possible inputs for anaerobic digestion (microalgal biomass and microalgal residue after lipid extraction) and the outputs resulting from the process (e.g. biogas and digestate). The strong interest in microalgae anaerobic digestion lies in its ability to mineralize microalgae containing organic nitrogen and phosphorus, resulting in a flux of ammonium and phosphate that can then be used as substrate for growing microalgae or that can be further processed to produce fertilizers. At present, anaerobic digestion outputs can provide nutrients, CO2 and water to cultivate microalgae, which in turn, are used as substrate for methane and fertilizer generation.Peer ReviewedPostprint (author's final draft

Marine bioinvasion: concern for ecology and shipping

Marine bioinvasion - introduction of marine organisms alien to local ecosystem through ship hulls and ballast water - has serious consequences to native biota, fishery and general coastal ecosystem. Over 80% of the world cargo is mobilized transoceanically and over 12 billion tones of ballast water is filled at one part of the ocean and discharged at the other. These ballast waters offer conducive situation for bacteria, viruses, algae, dinoflagellates and a variety of macro-faunal larval/cyst stages to translocate to alien regions, usually along the coasts of the continents. As an example, there are over 18 species of animals and plants documented along the Indian coasts as those that might have got invaded and established. They can cause deleterious effects to local flora and fauna through their toxigenic, proliferative and over-competitive characteristics. This article points out the threats arising out of marine bioinvasion and various technological developments needed to deal with this unavoidable scourge in global shipping transport

Prebiotics from Marine Macroalgae for Human and Animal Health Applications

The marine environment is an untapped source of bioactive compounds. Specifically, marine macroalgae (seaweeds) are rich in polysaccharides that could potentially be exploited as prebiotic functional ingredients for both human and animal health applications. Prebiotics are non-digestible, selectively fermented compounds that stimulate the growth and/or activity of beneficial gut microbiota which, in turn, confer health benefits on the host. This review will introduce the concept and potential applications of prebiotics, followed by an outline of the chemistry of seaweed polysaccharides. Their potential for use as prebiotics for both humans and animals will be highlighted by reviewing data from both in vitro and in vivo studies conducted to date

Marine Tar Residues: a Review

Abstract Marine tar residues originate from natural and anthropogenic oil releases into the ocean environment and are formed after liquid petroleum is transformed by weathering, sedimentation, and other processes. Tar balls, tar mats, and tar patties are common examples of marine tar residues and can range in size from millimeters in diameter (tar balls) to several meters in length and width (tar mats). These residues can remain in the ocean envi-ronment indefinitely, decomposing or becoming buried in the sea floor. However, in many cases, they are transported ashore via currents and waves where they pose a concern to coastal recreation activities, the seafood industry and may have negative effects on wildlife. This review summarizes the current state of knowledge on marine tar residue formation, transport, degradation, and distribution. Methods of detection and removal of marine tar residues and their possible ecological effects are discussed, in addition to topics of marine tar research that warrant further investigation. Emphasis is placed on ben-thic tar residues, with a focus on the remnants of the Deepwater Horizon oil spill in particular, which are still affecting the northern Gulf of Mexico shores years after the leaking submarine well was capped

Effects of Repeated SSRI Treatment on BDNF and TrkB Receptors in Adolescent Rats

The SSRI antidepressant fluoxetine is one of the few drugs that is both effective at treating depression in adolescent humans and does not markedly increase suicidal ideation. In contrast, the SSRI paroxetine has limited efficacy and is more at risk for inducing suicidal behavior. Thus, the goal of the present project is to further explore the differences between paroxetine and fluoxetine on the BDNF system in male and female adolescent rats. We will measure the levels of BDNF and the TrkB receptor after 24 h or 14 days after repeated (10 day) or chronic (30 day) exposure to paroxetine (2.5 or 10 g/kg), fluoxetine (10 mg/kg), and vehicle. Twenty-four hours or 14 days after the last drug injection, rats will be rapidly decapitated and their prefrontal cortex and hippocampus is removed. These tissue samples will be used to quantify BDNF, TrkB, and serotonin levels. We expect the BDNF and TrkB levels to be lower in rats treated with paroxetine but not fluoxetine. We also expect the serotonin utilization (ratio of serotonin to the major serotonin metabolite, 5HIAA to be higher in fluoxetine than in paroxetine. Our findings would confirm the neurobiological basis of the differential action of SSRIs on the adolescent brain and the relevant implication in suicidal ideation and behaviors

Effects Of Repeated Paroxetine And Fluoxetine Exposure On Hippocampal Bdnf Functioning In Adolescent Rats

The use of SSRIs in pediatric populations is limited due to reduced efficacy and their tendency to induce suicidal ideation in adolescents. Recently, we found that repeated treatment with fluoxetine and paroxetine caused increased anxiety-like behaviors in adolescent rats, as measured on the elevated plus maze and light/dark box. The purpose of the present study was to determine if changes in brain derived neurotropic factor (BDNF) functioning are responsible for mediating these age-dependent behavioral and neurochemical effects. The rationale for this study was based on a growing body of evidence suggesting that the therapeutic effects of antidepressants are dependent on BDNF-mediated increases in neurogenesis. To test our hypothesis, we measured the expression of BDNF and the BDNF receptor, after repeated paroxetine and fluoxetine treatment. Male and female adolescent Sprague Dawley rats (n=67) were injected with paroxetine (2.5 or 10 mg/kg), fluoxetine (5 or10 mg/kg), or vehicle for 10 consecutive days starting on postnatal day (PD) 35. On PD 45, the hippocampus of each rat was removed and then assayed for BDNF expression using western blotting. In both male and females rats, BDNF expression was decreased after fluoxetine (5 and 10 mg/kg) treatment. Paroxetine (10 mg/kg) also decreased BDNF levels, but only in male rats. Repeated treatment with the SSRIs paroxetine and fluoxetine led to decreased BDNF expression in adolescent rats. This reduction in BDNF levels may be responsible for the reduced efficacy of SSRIs during adolescence. Interestingly, paroxetine had a greater effect on the BDNF functioning of male rats than females

It's logical: innovating profitable business models

The book aims at exploring how business model innovation can be achieved logically by focusing on the user

Benthic marine algae of the inshore water at Vestfold Hills, Antarctica

110-114Distribution and composition of benthic marine algae were studied at 4 stations in the Ellis Fjord (Iat. 68° 35' and 68° 38' E; long. 77° 50' and 78° 15' S) Vestfold Hills, Antarctica. Algae were collected through drilled hole in sea ice from May to December 1983 and during summer in the intertidal zone. Of the 14 algal species recorded from Ellis Fjord and Vestfold Hills, Antarctica brown algae Himantothallus grandifolius and Desmarestia menziesii were abundant near the mouth of the Fjord, but apparently absent inside the Fjord. Red algae Palmaria decipiens and Phyllophora antarctica were the dominant species of the region. Porphyra endiviifolium occurred in the upper littoral zone while Urospora penicilliformis and Enteromorpha bulbosa occurred in the intertidal rock crevices and furrows. Monostroma hariotii was present both in the intertidal pool and in infralittoral zone. Decrease in nitrate concentration was related with the luxuriant growth of U. penicilliformis during December, which was evident from the increase in photosynthetic activity resulting into high dissolved oxygen and pH of the water

Effect of treated sewage on growth of marine algae

33-36Eight algal species belonging to Chlorophyta, Rhodophyta and Phaeophyta were used to assess the effect of different concentrations of secondary treated sewage on their growth. Chlorophyta and Rhodophyta members. Ulva fasciata and Gracilaria verrucosa respectively, showed good growth as compared to the control in 5% sewage-seawater medium. Phaeophyta members did not show satisfactory growth. However, in 5 and 10% sewage-seawater media growth was observed in Padina tetrastromatica, stoechospermum marginatum and Spatoglossum asperum, while Sargassum sp. was found to be least tolerant to sewage pollution. Correlation coefficients between algal growth (weight) and nutrients showed that U. fasciata and G. verrucosa can be cultivated in diluted sewage effluent as tertiary sewage treatment species to remove nutrients in high concentrations and toxic substances from the sewage polluted areas