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Microalgae hold promise as a sustainable source of biofuels and bioproducts but their commercial development is impeded by high cultivation costs, primarily for growth nutrients, and concerns about the water-intensive nature of algae cultivation. As a result, minimizing water and nutrient input is imperative to reducing algal operating costs, while enhancing the sustainability of future algal biorefineries. However, spent media recycling often results in the accumulation of growth inhibitors, such as free fatty acids, polysaccharides, polyunsaturated aldehydes, and humic acid, which negatively affect algal growth and productivity. In this review, we critically assess media recycling research findings to assess the advantages and disadvantages of spent media reuse for a wide range of algae strains. Particular emphasis is placed on strategies to overcome growth inhibition through spent media treatment processes, such as ultraviolet oxidation, activated carbon, ultrasonication, microfiltration, crop rotation, and nutrient replenishment. [ABSTRACT FROM AUTHOR]

Aquatic algae are a rich source of a wide range of bioproducts intended to compete for a sizable global market share. Thanks to the gradual shift towards the use of natural products, microalgae-derived bioactive compounds offer an ecofriendly and vegan option to the cosmeceutical sector, whose products aim to improve skin health but currently consist of mostly synthetic chemicals. In particular, algae-derived vitamins and their precursors are being explored and widely used in the cosmeceuticals industry as compounds that contain biologically active ingredients with therapeutic benefits. The present review highlights the current strategies for industrial production of an array of vitamins from algae for cosmeceutical applications. When compared to traditional plant sources, algae have been found to accumulate vitamins, such as A, B1, B2, B6, B12, C and E, in high concentrations. The purpose of this review is to provide context for the development of a green and sustainable algae-derived bioeconomy by summarizing and comparing the current market for vitamins and precursors derived from algae, as well as presenting novel strategies and key findings from the most recent research in this area. Emphasis is placed on novel biotechnological interventions that encompass genetic modifications, genetic engineering, and media development to enhance vitamin biosynthesis. [ABSTRACT FROM AUTHOR]

A promising feedstock for large‐scale production of sustainable jet biofuel is the inedible oilseed Brassica carinata (referred to simply as "carinata"), but transitioning to large‐scale fuel production entails significant economic uncertainty and requires substantial up‐front capital requirements for biorefinery construction. Furthermore, for carinata and other feedstocks attempting to compete within the established fossil jet fuel market, historically volatile aviation fuel prices affect the economic feasibility and return of biorefinery investments. In this study, we assess the impact of jet fuel price volatility on the return on investment in a carinata biorefinery employing a real options analysis (ROA). The key advantage of ROA over traditional net present value (NPV) analysis is that it simultaneously assesses the optimal timing for investments and the impact of jet fuel price dynamics on the likelihood of positive economic returns from investments in processing plants. Given the nonstationary nature of jet fuel prices and the presence of structural breaks, the price series are modeled as a geometric Brownian motion. Taking into account the volatility of jet fuel price, the ROA price threshold for a profitable investment is 45% greater than the NPV threshold. The ROA model identifies the necessary market conditions for a profitable investment and highlights the importance of considering market price dynamics before making substantial capital investments in a carinata biorefinery. [ABSTRACT FROM AUTHOR]

Brassica carinata or Ethiopian mustard, a non‐edible oilseed brassica, is a low carbon, purpose‐grown, and none‐to‐low indirect land‐use change bioenergy feedstock for the production of drop‐in sustainable aviation fuel, biodiesel, renewable diesel, and a suite of value‐added coproducts. Carinata oil converted to drop‐in fuel using an American Society for Testing and Materials approved Catalytic Hydrothermolysis process has been successfully tested in commercial and military aviation. Carinata meal, the residue after oil extraction, is a high‐protein feed supplement for livestock, poultry, and swine, and can also yield specialty products. The Southeast Partnership for Advanced Renewables from Carinata (SPARC) is a public–private partnership formed with a twofold mission: (1) Removing physical, environmental, social, and economic constraints that prevent regional intensification of carinata production as a low‐carbon feedstock for renewable fuel and coproducts and (2) demonstrating enhanced value across the entire value chain by mitigating risk to farmers and other stakeholders. The partnership's goal is to energize the US bioeconomy through sustainable agriculture and thus contribute to energy security and economic diversification. SPARC relies on a combination of cutting‐edge multidisciplinary research and active industry engagement to facilitate adoption of the crop. This involves informing stakeholders along the entire supply chain, from producers to end‐users, policymakers, influencers, and the public, about the opportunities and best practices related to carinata. This article provides context and background concerning carinata commercialization as a winter cash crop in the Southeast US for renewable fuels and bioproducts. The advances made to date in the areas of feedstock development, fuel and coproduct development, meal valorization, supply chain logistics, and stakeholder engagement are outlined. [ABSTRACT FROM AUTHOR]

The economics of the inedible oilseed crop Brassica carinata as a source of renewable fuels can be enhanced by converting its cellulosic biomass to value‐added chemicals, such as organic acids. We investigated the biochemical conversion of carinata biomass to propionic acid by first pretreating the carinata meal (CM), which is obtained after extraction of the oil from carinata seeds, with concentrated phosphoric acid to remove hemicellulose and gain access to the cellulose constituent of the meal. We then subjected the pretreated meal to enzymatic hydrolysis with cellulase enzyme to depolymerize cellulose to glucose. The overall conversion of carinata cellulose to glucose was 85%, which is promising. Finally, the recovered glucose was successfully fermented primarily to propionic acid using the bacterium Propionibacterium freudenreichii with a yield of 0.57 g of produced propionic acid per gram of consumed cellulosic glucose. The biobased propionic acid and other co‐produced organic acids can serve as renewable building blocks for manufacturing industrial chemicals and food preservatives replacing fossil‐derived organic acids. Hence, CM constitutes a renewable source of fermentable carbohydrates potentially improving the economics and sustainability of the carinata value chain. [ABSTRACT FROM AUTHOR]

• RUSLE has been coupled with the MAGNET model to estimate the global economic impacts of soil erosion. • The estimated annual cost to global GDP is eight billion US dollars. • Global agri-food production is reduced by 33.7 million tonnes. • Abstracted water volumes are driven upwards by an estimated 48 billion cubic meters. • Soil erosion accelerates shifts in comparative advantage on world agri-food markets. Employing a linkage between a biophysical and an economic model, this study estimates the economic impact of soil erosion by water on the world economy. The global biophysical model estimates soil erosion rates, which are converted into land productivity losses and subsequently inserted into a global market simulation model. The headline result is that soil erosion by water is estimated to incur a global annual cost of eight billion US dollars to global GDP. The concomitant impact on food security is to reduce global agri-food production by 33.7 million tonnes with accompanying rises in agri-food world prices of 0.4%–3.5%, depending on the food product category. Under pressure to use more marginal land, abstracted water volumes are driven upwards by an estimated 48 billion cubic meters. Finally, there is tentative evidence that soil erosion is accelerating the competitive shifts in comparative advantage on world agri-food markets. [ABSTRACT FROM AUTHOR]

• Assessment of food waste reduction impact needs to include economic and biophysical indicators. • Economy-wide models as proposed in this paper can account for all market and non-market impacts of reducing food waste. • Reducing households' food waste increases savings; it decreases agri-food production and to a minor extent GDP. • Environmental indicators are improving as EU land use, water abstraction and greenhouse gas emissions decline. Halving per capita food waste and reducing food losses along production and supply chains is one of the objectives fixed by the United Nations among the Sustainable Development Goals (SDGs). This study employs a system-wide modelling approach, to simulate economic impacts of households' food waste reduction in 2030, focusing on the European Union. The paper provides market, food security, biophysical and environmental indicators resulting from food commodity specific waste reductions by EU households. The scenarios explicitly account for associated costs paid by food manufacturers derived from adjustments in the packaging, labelling and logistics. The model shows, under a series of market assumptions, a possible increase in household savings, a fall in agri-food production and a minor negative macroeconomic impact due to household food waste reductions. On the other hand, the effects on environmental indicators such as land usage, GHG emissions and water abstraction are positive. Future research on several aspects of the food waste topic is needed to better integrate all economic aspects. [ABSTRACT FROM AUTHOR]

Modeling and optimization of key design parameters of bioreactors are critical for development of economically and technically viable algae technologies. The objective of this study is to use computational fluid dynamics (CFD) modeling to design a novel enclosed Horizontal BioReactor (HBR) equipped with a paddle wheel that incurs low capital and operating costs like raceway ponds, but achieves high productivities like enclosed photobioreactors. For the HBR the aspect ratio (length-to-width), paddle wheel diameter and positioning, culture depth, and baffle spacing can be manipulated to achieve adequate flow of the culture that minimizes the formation of low-velocity areas, below 20 cm/s, termed “dead zones”. The CFD procedure focused on minimizing dead volume and power consumption. A small-scale HBR (3 m 2 of surface area) was used for development and validation of the hydrodynamic model, whose parameters were calculated using experimental data. The model was then applied to a pilot-scale HBR (40 m 2 ) that is operated outdoors. Placing the paddle wheel at either end of the reactor or incorporating baffles minimized the dead volume. The same effect was also achieved by increasing the size of the paddle wheel or the number of paddle wheels or the depth of the culture. On the other hand, increasing the reactor's aspect ratio resulted in more dead volume, although it decreased power consumption. These findings will be incorporated into the design of large-scale HBRs (200 m 2 ) for commercial deployment. [ABSTRACT FROM AUTHOR]

Originally conceived as a post-war policy vehicle for ensuring agricultural self-sufficiency, the Common Agricultural Policy (CAP) has evolved into a multifunctional instrument designed to satisfy a diverse portfolio of European Union (EU) policy objectives including nature protection. Notwithstanding, whilst the CAP has become more environmental and socially responsible, it is still expected to deliver an efficient farm production system capable of competing on world markets. The current paper combines a farm business panel dataset for 98 EU territories with a Stochastic Frontier Analysis (SFA) approach, to assess the impact of four contemporary broad categories of CAP subsidy programs on efficiency and environmental sustainability. In accordance with the literature, this study more correctly defines inputs as “facilitating”, whilst following recent methodological developments, crop-subsidies are treated as an endogenous strategic variable in the production function. Comparing between two discrete time periods, further tests are conducted to examine the hypothesis of technical efficiency convergence across european territories. The results suggest that first pillar crop subsidies and pillar two environmental programs generate a disincentive effect on productivity, whilst in general, the CAP promotes technical efficiency convergence within Europe. [ABSTRACT FROM AUTHOR]

We employ a heavily modified 'agricultural' variant of the GTAP model and a realistic baseline scenario to assess the impact on the Greek economy from a hypothetical 'hub and spoke' and a 'FTA' EUMED agro-food and fisheries trade agreement. Long run estimates show that Greek agro-food and fisheries sectors are not seriously affected, where surprisingly, trade diversionary losses to Greece from the FTA scenario are minor given minimal south-south trade links between Mediterranean Partner Countries (MPC). Further research shows that under complete CAP decoupling, notable additional welfare gains for MPC are realised, whilst Greece stands to lose approximately €300 million. [ABSTRACT FROM AUTHOR]

Conversion of residual algal biomass to value-added products is essential for enhancing the economics of algae cultivation. Algal hydrochar produced via hydrothermal carbonization of lipid-extracted Picochlorum oculatum is a material rich in oxygen functional groups and carbon (up to 67.3%) and hence a promising candidate for remediation of wastewaters. The hydrothermal carbonization conditions were optimized and the adsorption capacity of the hydrochar was tested for metal removal. By the end of the remediation process, cumulative removal of Al3+, Cu2+, Fe2+, Mg2+, Mn2+, and Pb2+ reached 89, 98, 75, 88, 75, and 100%, respectively. The adsorption of all metals was found to follow pseudo second-order kinetics and the Langmuir isotherm. Overall, when hydrothermal carbonization is applied to lipid-extracted algae, it generates a promising biobased adsorbent with value-added potential in metal remediation. [ABSTRACT FROM AUTHOR]

• The impact of healthy diets to 2050 is examined within a global simulation model. • The baseline exposes regional 'pressure points' for virtual commodity consumption. • Diet change drives global falls (rises) in agricultural land and GHGs (water) consumption. • Sub-Saharan Africa benefits from a "rebound¨ effect due to cheaper meat and dairy prices. • The healthy diet switch requires an increase in per capita expenditure world wide. The importance of healthy diets is woven into the fabric of the Sustainable Development Goals, although there is no clear metric to define it. Employing a simulation model (MAGNET), this study examines the sustainability implications arising from the adoption of recommended daily nutrition requirements inspired by the 'Lancet' reference diet. To measure sustainability, changes in 'virtual' requirements and associated tier footprints for irrigation (blue) water, agricultural land and greenhouse gas emissions (GHG) are calculated. Assuming business-as-usual food consumption trends, between 2015 and 2050 blue water, agricultural land and emissions rise 34%, 9% and 44%, respectively, whilst corresponding increases in Sub-Saharan Africa are much higher. By 2050, the switch to the reference diet decreases agricultural land use by -8% and emissions by -9%. Global blue water and cropland requirements increase by 5%, whilst significant concomitant savings in permanent pastureland (-21%) are expected. By region, the diet switch drives rising blue water consumption in Oceania and the EU and agricultural land savings in Latin America and Oceania, accompanied by cropland increases in the EU and North Africa. The reference diet generates substantial reductions in GHG emissions, particularly in Latin America. Interestingly, Sub-Saharan Africa which abstains from the reference diet due to affordability considerations, benefits from a 'rebound' effect from falling meat and dairy prices. Finally, the diet shift could result in marginal per capita food expenditure rises arising from demand driven fish price, particularly in more vulnerable world regions. This estimate does not capture, however, second-round economic growth effects arising from increased labour productivity and reduced public health expenditures. [ABSTRACT FROM AUTHOR]