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Abstract The growing population, decreasing arable land and fresh water supply questions the sustainability of terrestrial agriculture for securing safe nutrients supply, particularly starch- an essential ingredient for all staple foods. Here, we report the isolation, characterization and offshore production assessment of native starch from green seaweed Ulva ohnoi cultivated in seawater. Starch content varied from 1.59% to 21.44% depending on growth conditions and seasons. Our results show that nutrient starvation significantly increased the starch concentration up to 21.4% on dry weight basis. The extracted fraction contained 75.45% starch, and the starch extraction yield from the U. ohnoi biomass was 50.37%. Ulva starch granules are spherical, ovoid and irregularly shaped, 5–7 μm in size. Their gelatinization temperature is 69° C and they are susceptible to α-amylase and amyloglucosidase digestion. U. ohnoi biomass cultivated offshore for 13 months showed an average starch yield of 3.43 ton/ha/year (t·ha−1y−1). This study encourages the potential use of offshore produced biomass for sustainable starch supply as an alternative to current agricultural products, the production of which requires arable land and fresh water. Graphical abstract Unlabelled Image Highlights • Starch content of Ulva was 1.59% to 21.44% DW, rising with nutrient starvation. • Native granular starch extracted by food grade methods (75.4% purity, 50.37% yield). • Morphology, size, thermal properties and digestibility were studied. • Annual production of Ulva starch was monitored in offshore sea environment. • Average starch yield of 3.43 ton/ha/year (t·ha−1y−1) on DW basis was observed. [ABSTRACT FROM AUTHOR]

To foster the development of macroalgal biomass for biorefinery applications, we tested two orthogonal techniques for rapid phenotyping of the green macroalga Ulva based on its glucose, rhamnose, xylose and glucuronic acid contents as derived for reference by acid hydrolysis. Partial Least Squares (PLS) regression analyses, calculation of slopes and correlations across different spectral ranges/frequencies were used to predict the monosaccharide contents using two complementary methods: near infrared reflection spectroscopy (NIRS) and microelectromechanical systems (MEMS) resonating membrane vibrometry. Both methods were found to perform sufficiently well in monosaccharide mixtures and to enable quantitative assessment of different monosaccharide contents with the relative Root Mean Square Error of Prediction (%RMSEP) ranging from 8 to 16% (with similar accuracy when using PLS analyses). The best estimation was found for rhamnose and glucose contents, whereas xylose and uronic acid content predictions were found to be less accurate using PLS analyses. For the two latter components, slopes across different spectral ranges and frequencies at certain signals provided better estimates for their concentrations (e.g. for NIRS slopes: R 2 values in the range 0.55–0.66 and with higher accuracy for MEMS: between 0.75 and 0.90). This result is pivotal for opening new perspective to the construction of simple, multi-functional sensors for biomass downstream processing control in biorefinery and biometric applications. [ABSTRACT FROM AUTHOR]

Seaweed farming, or seagriculture, is expected to provide sustainable biomass enabling the development of marine bioeconomy through the blue growth. Epiphytism is a common phenomenon in seaweed farming that impacts the biomass yield. Epiphytes may be other non-wanted algal species, viruses, bacteria, and fungi. Epiphytes can attract grazers such as crabs, lobsters, shrimp, crayfish, fish, and turtles, which have both positive (enriched biodiversity throughout the food chain, ecosystem services, etc.) and negative (yield loss, etc.) impacts on seaweed farming. A critical challenge for the future seagriculture is how to address the pest problem. Although well developed for terrestrial agriculture, pest management frameworks for seaweed farming have yet to be set up. In this regard, we propose a framework for marine integrated pest management in seaweed farming. Based on several cases-studied: indoor and offshore seaweed farming in Israel and traditional seaweed farming in India, pest prevention, pest control, pest mitigation strategies and their implementations are discussed. [ABSTRACT FROM AUTHOR]

Macroalgae are primary producers bearing key roles in the normal functioning of marine environments. The critical energy carriers that macroalgae produce are carbohydrates, which support marine ecosystems and are used in biorefineries. In this work, we quantified the monosaccharide content and diversity of macroalgal species common to the Eastern Mediterranean shores representing the three major seaweed divisions, namely, Chlorophyta ( Ulva sp. and Cladophora pellucida ), Rhodophyta ( Nemalion helminthoides , Galaxaura rugosa and Gracilaria sp.) and Ochrophyta ( Padina pavonica and Sargassum vulgare ). We found that the most abundant monosaccharide was different in 5 out of the 7 investigated species. The monosaccharide diversity profile was specific to each taxonomic group, especially in the first two orders of diversity, which correspond to Shannon entropy and Simpson concentration. The content of monosaccharides released by acid hydrolysis varied by 153% between Ulva sp., C. pellucida , G. rugosa , N. helminthoides , Gracilaria sp., P. pavonica , and S. vulgare collected from the same site. Ulva sp. collected at different sites at different months showed up to 79% variance in the total released monosaccharides, with up to 270% variance in the content of individual monosaccharides. The cultivation of Ulva sp. in a photobioreactor under more stable conditions reduced the diversity and the variability of the total carbohydrates to only 2%. By comparing amounts and types of monosaccharides derived from macroalgae, microalgae and terrestrial plants, it appears that Ulva sp. has the highest economic potential of all photosynthetic organisms, between $1733 kg − 1 and $3140 kg − 1 of Ulva biomass. [ABSTRACT FROM AUTHOR]

Wound healing is an incredibly complex biological process that often results in thickened collagen-enriched healed tissue called scar. Cutaneous scars lack many functional structures of the skin such as hair follicles, sweat glands, and papillae. The absence of these structures contributes to a number of the long-term morbidities of wound healing, including loss of function for tissues, increased risk of re-injury, and aesthetic complications. Scar formation is a pervasive factor in our daily lives; however, in the case of serious traumatic injury, scars can create long-lasting complications due to contraction and poor tissue remodeling. Within this report we target the expression of connective tissue growth factor (CTGF), a key mediator of TGFβ pro-fibrotic response in cutaneous wound healing, with controlled local delivery of RNA interference. Through this work we describe both a thorough in vitro analysis of nanolayer coated sutures for the controlled delivery of siRNA and its application to improve scar outcomes in a third-degree burn induced scar model in rats. We demonstrate that the knockdown of CTGF significantly altered the local expression of αSMA, TIMP1, and Col1a1, which are known to play roles in scar formation. The knockdown of CTGF within the healing burn wounds resulted in improved tissue remodeling, reduced scar contraction, and the regeneration of papillary structures within the healing tissue. This work adds support to a number of previous reports that indicate CTGF as a potential therapeutic target for fibrosis. Additionally, we believe that the controlled local delivery of siRNA from ultrathin polymer coatings described within this work is a promising approach in RNA interference that could be applied in developing improved cancer therapies, regenerative medicine, and fundamental scientific research. [ABSTRACT FROM AUTHOR]

Displacing fossil fuels with renewables and increasing sustainable food and chemicals production are among the major challenges facing the world in the coming decades. Integrating climatological oceanographic data with a metabolism and growth rate model of the green marine macroalga from Ulva genus, we analyze the potential of offshore biorefineries to provide for biomass, ethanol, butanol, acetone, methane and protein, globally and in 13 newly defined offshore provinces. We show that for optimum fresh weight stocking density of 4 kg m − 2 the total potential of offshore cultivated Ulva biomass is of the order of 10 11 dry weight (DW) ton year − 1 , over a surface area of ~ 10 8 km 2 . We found that the distance of the offshore cultivation site to the processing facility is limited to 114–689 km, depending on cargo moisture content. The near-future technologically deployable areas, associated with up to 100 m water installation depth, and 400 km distance from the shore, can provide for 10 9 DW ton year − 1 , which is equivalent to ~ 18 EJ. This has the potential to displace entirely the use of fossil fuels in the transportation sector or provide for 5–24% of predicted plant proteins demand in 2054. In addition, we modeled the potential production of ethanol, butanol, acetone and methane from the offshore produced biomass. Finally, we analyzed the environmental risks and benefits of large-scale offshore macroalgal cultivation. These results are important as they show for the first time the potential of offshore biomass cultivation to reduce the use fossil fuels and arable land to provide for food, chemicals and fuels required for the society. [ABSTRACT FROM AUTHOR]

Marine algal biofuel is considered a promising solution for energy and environmental challenges. Macroalgal biomass has the potential for bypassing the shortcoming of first and second generation of biomass from food crop and lignocellulosic sources. In this review, we summarize the findings in this domain in the past two decades with a focus on the process of saccharification and fermentation of macroalgae for transportation biofuels. In general, macroalgae contains high levels of carbohydrates, almost no or comparatively less lignin than in terrestrial plants, which makes it a very promising source for liquid biofuel production via bioconversion. After harvest, macroalgal biomass goes through several process units, including pre-treatment and/or saccharification and fermentation to be converted to biofuel, e.g., bioethanol. We also propose strategies for further studies to realize macroalgae biomass potential for transportation bioenergy production. [ABSTRACT FROM AUTHOR]

Biorefineries aim to provide sustainable production of food and generation of low carbon energy in the next decades. Current strategies for biorefinery reply mostly on the classic terrestrial agriculture for biomass production. However, land availability, competition with food crops and total energy balance are challenging limiting factors for terrestrial bioenergy crop production. Off-shore macroalgae production could provide alternative, sustainable feedstocks for biorefineries without competition with food crops. Increasing the yields of off-shore macroalgae cultivation systems could further improve the total energy balance of the marine biorefineries. In this work, based on the fundamental principle of timing differences between light harvesting and carbon fixation in algae, we developed a theoretical framework for increasing the yields of off-shore macroalgae biomass using external mechanical mixing. We show that for a given physiological parameter of macroalgae light harvesting and carbon fixation, mixing could allow for increase of the total energy gain by two orders of magnitude. The overall biorefinery to biofuel efficiency, however, is constrained by drag and macroalgae thallus size. [ABSTRACT FROM AUTHOR]

Exergy analysis methods place a major emphasis on technological and economical optimization of energy systems but have limited ability to address their environmental impacts. Although several approaches, such as Extended Exergy Accounting and Exergonomics, have been proposed to include pollution costs in the energy system optimization, environmental impacts of energy systems are much more complex, as energy systems affect the entire eco-systems services in the areas they are installed. Therefore, energy systems should minimize the adverse impacts on the surrounding eco-system services. In this paper we introduce a method for analysis and optimization of energy systems using technological, economic, and environmental exergy flows. For environmental exergy flow analysis, we included the eco-exergy component in the system objective function. Eco-exergy provides a Second Law derived measurement of the eco-system ability to do work. The disruption of eco-system services, such as reduction of biodiversity, is reflected in a reduction of eco-exergy. Therefore, we propose to include the minimization of the eco-exergy losses in the sustainable energy systems optimization. To demonstrate the method, we analyzed the eco-exergy losses associated with the reduction of the birds' biomass in the EU (European Union) fields dedicated to renewable energy systems. Specifically, we show that the EU renewable energy installations in 2008 lead to addition, today unaccountable, 5 PJ exergetic losses associated with the reduction in the biodiversity and biomass. [ABSTRACT FROM AUTHOR]

• Solar-thermal seaweed biorefinery with offshore intensively grown biomass was analysed. • Co-production of protein, hydrochar, ethanol, distilled water and electricity was analysed. • The overall First Law efficiency is 32% and can reach 40% with energy recovery from aqueous phase. • Seaweed, electricity and protein prices are key for the profitability of the biorefinery. • The lowest environmental impacts are achieved with HDPV cage, PV electricity, and rail transport. Combing solar energy with biomass processing facilities are emerging systems for efficient use of solar energy for electricity generation, energy storage, and production of renewable materials. In this work, we propose a novel combination of solar thermal energy systems with marine macroalgae biorefinery, which requires energy inputs for biomass cultivation and processing. In this work, we analyze a 10-ton dry weight per hour capacity pilot-scale hybrid solar seaweed biorefinery, located at the Mishor Rotem near Dimona, the current location for solar-thermal projects in Israel, where seaweed biomass supply comes from a hypothetical offshore farm located 15 km offshore. Our energy and mass balance analysis show that the overall First Law efficiency of the hybrid solar seaweed biorefinery system for the co-production of protein, hydrochar, ethanol, distilled water, and electricity is 32% and can exceed 40% with additional waste stream recycling. Our cost-benefit analysis of the proposed solar-seaweed biorefinery shows that the prices of seaweed, electricity, and protein are the key drivers of the profitability of the production process. The environmental impacts of the hybrid solar-seaweed biorefinery with intensified offshore cultivated biomass were quantified under various seaweed cultivation, transportation, and processing strategies. [ABSTRACT FROM AUTHOR]

Seagriculture, which can provide offshore grown macroalgae biomass would play a significant role in bioeconomy. Nevertheless, seagriculture development has been hindered by the lack of laboratory photobioreactors that enable fundamental and pilot scale macroalgae research. In this work, a macroalgae photobioreactor (MPBR) was developed and integrated into the building. The MPBR operation was demonstrated for 6 months with cultivation of Cladophora sp., Ulva compressa and Ulva rigida green macroalgae species isolated from 3 sites at the Eastern Mediterranean coast. The growth rate, protein, ash, specific energy density, rhamnose, xylose, arabinose, glucose, galactose and glucuronic acid content of the cultivated species were quantified. The maximum accumulated energy rates were 0.033 Wh L −1 d −1 for Cladophora sp., 0.081 Wh L −1 d −1 for U. compressa and 0.029 Wh L −1 d −1 for U. rigida . This work provides a detailed design of an indoor, urban photobioreactor for cultivation, maintenance and energy balance analysis of macroalgae biomass for biorefinery. [ABSTRACT FROM AUTHOR]

The design of effective electroporation protocols for molecular delivery applications requires the determination of transport parameters including diffusion coefficient, membrane resealing, and critical electric field strength for electroporation. The use of existing technologies to determine these parameters is time-consuming and labor-intensive, and often results in large inconsistencies in parameter estimation due to variations in the protocols and setups. In this work, we suggest using a set of concentric electrodes to screen a full range of electric field strengths in a single test to determine the electroporation-induced transmembrane transport parameters. Using Calcein as a fluorescent probe, we developed analytical methodology to determine the transport parameters based on the electroporation-induced pattern of fluorescence loss from cells. A monolayer of normal human dermal fibroblast (NHDF) cells were pre-loaded with Calcein and electroporated with an applied voltage of 750 V with 10 and 50 square pulses with 50 μs duration. Using our analytical model, the critical electric field strength for electroporation was found for the 10 and 50 pulses experiments. An inverse correlation between the field strength and the molecular transport time decay constant, and a direct correlation between field strength and the membrane permeability were observed. The results of this work can simplify the development of electroporation-assisted technologies for research and therapies. [ABSTRACT FROM AUTHOR]

In this study we describe a simple lab-on-a-chip (LOC) biosensor approach utilizing well mixed microfluidic device and a microsphere-based assay capable of performing near real-time diagnostics of clinically relevant analytes such cytokines and antibodies. We were able to overcome the adsorption kinetics reaction rate-limiting mechanism, which is diffusion-controlled in standard immunoassays, by introducing the microsphere-based assay into well-mixed yet simple microfluidic device with turbulent flow profiles in the reaction regions. The integrated microsphere-based LOC device performs dynamic detection of the analyte in minimal amount of biological specimen by continuously sampling micro-liter volumes of sample per minute to detect dynamic changes in target analyte concentration. Furthermore we developed a mathematical model for the well-mixed reaction to describe the near real time detection mechanism observed in the developed LOC method. To demonstrate the specificity and sensitivity of the developed real time monitoring LOC approach, we applied the device for clinically relevant analytes: Tumor Necrosis Factor (TNF)-α cytokine and its clinically used inhibitor, anti-TNF-α antibody. Based on the reported results herein, the developed LOC device provides continuous sensitive and specific near real-time monitoring method for analytes such as cytokines and antibodies, reduces reagent volumes by nearly three orders of magnitude as well as eliminates the washing steps required by standard immunoassays. [ABSTRACT FROM AUTHOR]

Neoteric phenomena such as climate change, scarce water availability and excessive fertilizer usage necessitate an augmentation of resource utilisation efficiencies in the agricultural sector. There is a need to reorient the agroecosystems to curb stress on environmental resources while meeting rising socio-economic objectives under changing hydro-climatic conditions. Considering this, optimal land allocation for diversified agriculture is essential. We propose a combinatorial optimisation approach for land allocation considering agronomic, socio-economic, environmental and hydro-climatic objectives using bio-inspired optimization algorithms. The stochastic approach tackles the problem of optimal agricultural land allocation for crops in a multidimensional context by simultaneously addressing the conflicting goals of farm-level risk management as well as district-level contingency planning. The efficiencies and sensitivity of the proposed framework are assessed through a case study of the Dharwad district in Karnataka, India using the data (water and fertilizer consumption and cost, crop type, cultivable land, man and machine hours, etc.) from the year 2019–2020. Results indicate that Multi-objective Genetic Algorithm (MOGA) is more capable of optimising agricultural resources management by suggesting optimal land allocation for diversified crop planning. Although Cuckoo Search (CS) and Particle Search Optimisation (PSO) also produced productive Pareto fronts, they were observed to be less effective than MOGA. The annual increase in profits and crop yield obtained using MOGA are 103% and 97% respectively, while water usage is reduced by 5% compared to the conventional routines in Dharwad. The proposed hydro-agronomic decision support framework (DSF) can be utilised to assist the AI-enabled crop planning process for the sustainable management of agroecosystems. [Display omitted] • Artificial intelligence (AI) framework for multi-scalar diversified agriculture. • Socio-economic, agronomic, hydro-climatic and environmental objectives for improving profits. • Comparison of MOPSO, MOGA and MOCS with traditional approach. • Multi-objective genetic algorithm improves profit and crop yield. [ABSTRACT FROM AUTHOR]

The green marine macroalgae Ulva sp. can reach a high protein content and a high composition of essential amino acids. In this study, we have developed a novel device and investigated the parameters for a continuous Pulsed Electric Field (PEF) process, coupled with enzyme treatment followed by a spray drying, to facilitate the aqueous fractionation of Ulva protein. The process demonstrated 8.79 ± 0.58 (% w/w) protein extraction yield. Furthermore, the aqueous fractionation of protein exhibited a substantial 41.45% essential amino acid content and a branched amino acids composition of 17.58%. Additionally, it displayed an in vitro relative digestibility of 87.4 ± 1.36% compared to soy protein, along with a water holding capacity of 7.15 ± 0.17 g water/g sample and an oil holding capacity of 1.76 ± 0.11 g oil/g sample. These findings suggest that employing a continuous PEF process in conjunction with enzyme-induced cell wall degradation could position green marine macroalgae as an important potential source for food protein ingredients. [Display omitted] • Novel device for continuous PEF processing for efficient protein extraction from green marine macroalgae Ulva sp. • Coupled enzyme treatment, PEF, and water extraction yielded 8.79 ± 0.58% protein extraction. • Ulva protein has 41.45% essential amino acids, valuable for human nutrition. • Extracted Ulva protein shows 87.4 ± 1.36% digestibility, with good water and oil holding capacities for food use. • Green marine macroalgae extract, processed using PEF and enzymes, shows food potential. [ABSTRACT FROM AUTHOR]

Highlights • Method for selective allergens extraction with pulsed electric fields. • Protein extraction with the pulsed electric field from Ulva sp. was optimized. • Allergy assessment of proteins extracted from the seaweed Ulva sp. • Proteomic analysis of Ulva sp. Abstract Extraction of protein from macroalgae, currently defined as "novel food", is challenging and limited information about the health impacts of these proteins is available. Here, we report on a non-thermal, chemical-free green macroalgae Ulva sp. protein extraction by osmotic shock combined with pulsed electric fields (PEF) followed by hydraulic pressure. The extracted proteins were identified and annotated to allergens using sequence similarity. The allergenicity potential of PEF extracted proteins was compared to osmotic shock extracts and complete Ulva sp. proteome, extracted with the thermochemical method. The PEF extracts contained 'superoxide dismutase' (SOD), a known food allergen, osmotic shock extract contained 'troponin C', and thermochemical extract contained two additional potential food allergens 'aldolase A' and 'thioredoxin h'. This study shows an importance and the need for deep investigation of algal proteins and protein extraction technology health impacts prior to large-scale release to the market of "novel food" derived proteins. [ABSTRACT FROM AUTHOR]

Abstract With rising global population and decreasing available land and fresh water resources, the oceans provide an attractive domain for sourcing nutrients. The marine macroalgae Ulva sp. and Gracilaria sp. are candidate raw biomass. Ulva sp. has high growth rate and Gracilaria sp. has high protein content and their seasonal growth is complementary, allowing almost year-round high yield protein production. In this study, we aimed at developing an effective process, to yield a high macroalgae protein content concentrate suitable for food application, and studying the digestibility, amino acid composition and antioxidant properties of the obtained algal protein concentrates (APCs). We developed a new protein extraction protocol, and compared it to several published protocols. The developed protocol is food-grade, and yielded APC from Ulva and form Gracilaria , containing 70 and 86% protein respectively. The amino acid compositions of the APCs suggest their possible use as sources of essential amino acids. Simulated gastro-intestinal digestion showed that APCs proteolysis of at least 89% can be reached. We found that the APCs exhibit antioxidant activity, which is similar to that of known protein isolates in the hydrogen atom transfer mechanism, but 10 to 20 times higher in the single electron transfer mechanism. These results suggest that polyphenolic compounds might be still present in the APCs and contribute to their antioxidant activity. Our results suggest that the protein concentrates extracted from Ulva sp. and Gracilaria sp. seem to be promising sustainable sources for human nutrition thanks to their essential amino acids content, digestibility and antioxidant properties. Graphical abstract Image 1 Highlights • Macroalgae – a new and renewable source for extracted nutrients. • Food grade extraction yielded high purity protein powders. • Extracted proteins contain good levels of essential amino acids. • Protein concentrates exhibit high antioxidant activity. • Extracted proteins were ∼90% digestible under simulated gastro-intestinal conditions. [ABSTRACT FROM AUTHOR]

Abstract Meat waste has significant economic and environmental costs in the food supply chain. New approaches for meat waste conversion to products are needed. In this work, we developed a pulsed electric field-based process for functional chemicals extraction from waste chicken breast muscle. We show that a two-step protocol, which consists from high voltage, short pulses followed by low voltage long pulses, with the total invested energy of 38.4 ± 1.2 J g−1, of initial waste meat, enables extraction of 12 ± 2% of the initial waste chicken biomass to the liquid fraction. The protein content of the extract fraction was 78 ± 8 mg mL−1. In silico analysis also suggested that the extracted proteins could have antioxidant properties. This was corroborated experimentally with DPPH and ABTS assays. Process parameters analysis with Taguchi methodology showed that long pulse duration played the most important role in liquid extraction from the waste chicken breast muscle, followed by short pulses duration, number of long and short pulses. Our study suggests that pulsed electric fields combined with mechanical pressing can be used for extraction of functional molecules from the waste meat biomass using non-thermal, chemical-free process. Such a strategy could provide an additional income and thus, stimulate farmers and meat processors to reduce waste and waste-related environmental pollution. Highlights • Extraction of functional chemicals from waste chicken meat. • Use of pulsed electric fields for extraction of water-soluble molecules from chicken meat. • Application of Taguchi methodology for optimization of extraction process parameters. • Value addition for meat waste biorefinery. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Macroalgae as carbon source for polyhydroxyalkanoate accumulation in Haloferax mediterranei. • Utilization of Ulva sp. hydrolysate for PHA production with halophilic archaea. • Application of extreme halophilic archaea for PHA production. • Seagriculture for sustainable PHA production. Abstract Non-conventional carbon sources, such as macroalgae, are sustainable alternatives for large-scale production of biopolymers. The present study examined macroalgae-derived carbohydrates, as carbon sources for the production of polyhydroxyalkanoates (PHAs) by Haloferax mediterranei. Simulants of the hydrolysates of seven different macroalgal biomasses were prepared and the PHA production was studied. A maximum biomass concentration with maximum PHA content was detected in medium prepared from green macroalgae. The highest cell dry weight and PHA concentrations were 3.8 ± 0.2 g·L−1 and 2.2 ± 0.12 g·L−1 respectively when Haloferax mediterranei was grown in 25% (w/w) of Ulva sp. hydrolysate, at 42 °C temperature and initial pH of 7.2. Poly(3-hydroxy-butyrate-co-3-hydroxyvalerate was the major PHA constituent. The present study demonstrated that Ulva sp. is a promising feedstock for PHA production. [ABSTRACT FROM AUTHOR]

Offshore production of macroalgae biomass, which was recently given the name seagriculture, is one of the important but least explored alternative energy resources. Unlike microalgae, macroalgae cultivation can be done offshore and therefore brings real news to the biofuel – food land agriculture conflict. A wide variety of small-scale laboratory experiments are done lately in order to deepen the knowledge and develop expertise in macroalgae cultivation and its downstream processing. For energy applications, it is common to evaluate the performance of an energy source or system in exergy efficiency terms. Another important parameter that is evaluated to determine the system's environmental impact is it’s volumetric and areal footprint. The current work examines two exergy efficiency indexes, the Exergy Efficiency (EE), which takes into account all exergy inputs, and the Exergy Return On Investment (ExROI), that includes only fossil fuel exergy inputs, both on a green macroalgae Ulva grown in the macroalgae photobioreactor system (MPBR) incorporated into a building. Cultivation of macroalgae in the building embedded MPBR achieved maximal values of 0.012 and 0.22 for EE and ExROI, compared to a range of 0.05–8.34 and 0.013–0.327 found in published papers of microalgae systems. In addition, a modelled optimization of the initial biomass density leads to maximal values of about 0.035 for EE and 0.433 for ExROI, while further improvement may be achieved by optimization of nutrient addition and mixing methodology. This work demonstrates a tool to measure the performance of laboratory scale macroalgae biomass cultivation systems, followed by preliminary efficiency and environmental impact values, important for future upscaling. [ABSTRACT FROM AUTHOR]

Among all biomass constituents, the ashes are major hurdles for biomass processing. Ashes currently have low market value and can make a non-negligible fraction of the biomass dry weight significantly impacting its further processing by degrading equipment, lowering process yield, inhibiting reactions and decreasing products qualities. However, most of the current treatments for deashing biomass are of poor efficiency or industrial relevance. This work is the first report on the use of Pulsed Electric Field (PEF) to enhance deashing of biomass from a high ash content green marine macroalga, Ulva sp., using hydraulic pressing. By inducing cell permeabilization of the fresh biomass, PEF was able to enhance the ash extraction from 18.4% (non-treated control) to 37.4% of the total ash content in average, significantly enhancing the extraction of five of the major ash elements (K, Mg, Na, P and S) compared to pressing alone. [ABSTRACT FROM AUTHOR]

Offshore grown macroalgae biomass could provide a sustainable feedstock for biorefineries. However, tools to assess its potential for producing biofuels, food and chemicals are limited. In this work, we determined the net annual primary productivity (NPP) for Ulva sp. (Chlorophyta), using a single layer cultivation in a shallow, coastal site in Israel. We also evaluated the implied potential bioethanol production under literature based conversion rates. Overall, the daily growth rate of Ulva sp. was 4.5 ± 1.1%, corresponding to an annual average productivity of 5.8 ± 1.5 g DW m −2 day −1 . In comparison, laboratory experiments showed that under nutrients saturation conditions Ulva sp. daily growth rate achieved 33 ± 6%. The average NPP of Ulva sp . offshore was 838 ± 201 g C m −2 year −1 , which is higher than the global average of 290 g C m −2 year −1 NPP estimated for terrestrial biomass in the Middle East. These results position Ulva sp. at the high end of potential crops for bioenergy under the prevailing conditions of the Eastern Mediterranean Sea. We found that with 90% confidence, with the respect to the conversion distribution, the annual ethanol production from Ulva sp. biomass, grown in a layer reactor is 229.5 g ethanol m −2 year −1 .This translates to an energy density of 5.74 MJ m −2 year −1 and power density of 0.18 W m −2 . Growth intensification, to the rates observed at the laboratory conditions, with currently reported conversion yields, could increase, with 90% confidence, the annual ethanol production density of Ulva sp. to 1735 g ethanol m −2 year −1 , which translates to an energy density of 43.5 MJ m −2 year −1 and a power density 1.36 W m −2 . Based on the measured NPP, we estimated the size of offshore area allocation required to provide biomass for bioethanol sufficient to replace 5–100% of oil used in transportation in Israel. We also performed a sensitivity analysis on the biomass productivity, national CO 2 emissions reduction, ethanol potential, feedstock costs and sizes of the required allocated areas. [ABSTRACT FROM AUTHOR]

Economic and environmental developments in the last decades call for the displacement of fossil fuels to alternative energy sources. Biofuels are considered as a part of the solution for this challenge. Sustainable raw materials for the production of transportation biofuels such as biodiesel, biobutanol and bioethanol, can be obtained from algal biomass. In particular, marine macroalgal biomass is a promising feedstock for transportation biofuels because of (the) its fast growth and its potential cultivation on seawater, avoiding competition of resources with conventional agriculture of terrestrial plants used for food. In addition, dissolved inorganic nutrients like nitrogen, phosphorous and carbon are taken up by macroalgae, helping to alleviate eutrophication in seas and oceans. Using biological, chemical and engineering advances in the last decades, technologies to provide cost efficient cultivation, harvesting, extraction and processing of sustainable biofuels have to be elaborated. This paper provides a review of macroalgae based biorefineries with offshore cultivation and consequent biomass conversion into transportation liquid biofuels. We discuss the methods for offshore cultivation, harvesting, and conversion of macroalgae biomass into liquid transportation biofuels. Based on the current information and global experience, we present local perspectives specific for France, Germany, Norway, the Netherlands and Israel on the potential use of Exclusive Economic Zone for transportation biofuels production. Marketable suggestions for future research need to include all stakeholders of a given site for offshore biorefinery development. [ABSTRACT FROM AUTHOR]

Marine macroalgae are an attractive source of alternative protein. However, protein extraction from macroalgae is challenging. In this work, we investigated a combination of enzymatic cell wall degradation and high voltage Pulsed Electric Fields (PEF), to enhance yields of water-soluble-protein extraction from the green marine macroalga Ulva sp. The combined process showed a considerably higher protein extraction yield (19.6 ± 0.33%) compared to that of PEF alone (10.8 ± 0.37%) and enzyme pretreatment alone (9.7 ± 0.42%). Moreover, the water-soluble-protein extract obtained by PEF, which followed enzymatic cell wall degradation, had significant antioxidant activity. These results indicate that PEF combined with enzymatic pretreatment could contribute to protein extraction yields from Ulva sp., as a part of sustainable seaweed biorefinery. Although several previous works reported on methods for protein extraction from seaweeds for food application, the commercialization of the seaweed proteins is challenging due to multiple challenges in the extraction process development. In this work we show that a combination of enzymes for cell wall degradation with high voltage pulsed electric fields for membrane permeabilization lead to higher yields of water-soluble proteins. Both enzyme treatment and PEF are scalable processes, which do not modify proteins chemically, potentially leading to higher quality of the extract in comparison to standard alkaline extraction with a need to treat chemical waste. • Protein extraction from macroalgae Ulva sp. is challenging. • A combination of cellulase with Pulsed Electric Fields to extract protein was investigated. • The combined process showed 19.6 ± 0.33% protein extraction yield. • The water-soluble-protein extract had significant antioxidant activity. • The specific energy consumed relative to the wet mass of Ulva sp. was 79.1 ± 1.44 kJ kg−1 [ABSTRACT FROM AUTHOR]

Macroalgae are potential feedstock for biorefineries. However, integration of macroalgae into biorefinery network requires new processing technologies that will lead to energy efficient and zero waste conversion of macroalgae biomass into food, chemicals and fuels. Here we report on the selective extraction of proteins from green macroalgae from Ulva genus by electroporation with energy efficient pulsed electric field (PEF) process. We show that application of 75 pulses with an average electric field strength of 2.964 ± 0.007 kV cm − 1 , and pulse duration 5.70 ± 0.30 μs, delivered at approximately 0.5 Hz, combined with hydraulic pressing of the treated samples for 5 min with force of 45 daN cm − 2 led to the total protein concentration of 59.13 ± 3.82 μg mL − 1 in the extracted juice. The final temperature of the extracted juice was 35.50 ± 2.02 °C. The energy consumption of the process is 251 ± 3 kWh kg − 1 of protein. We show that PEF process is selective and its extraction efficiency and damage are protein specific. [ABSTRACT FROM AUTHOR]

[Display omitted] • C. amphilecti strain isolated from Ulva sp. was used for the biosynthesis of PHB. • PHB was generated from mannitol-rich agriculture wastes by C. amphilecti. • Methyl levulinate is a novel renewable and non-chlorinated PHB extraction solvent. • High recovery yield and purity of PHB were obtained with methyl levulinate solvent. The present study explored the use of mannitol and mannitol-rich agro-industrial wastes as substrates for PHB production by Cobetia amphilecti isolated from the green Ulva sp. seaweed. Cultivation of C. amphilecti on mannitol, celery, and olive leaves (OLs) waste led to 4.20, 6.00, and 5.16 g L−1 of cell dry mass (CDM), 76.3, 25.5, and 12.0% of PHB content in CDM and 3.2, 1.53, and 0.62 g L−1 of PHB concentration, respectively; which suggested that they can be exploited as carbon substrates for the production of PHB. Extraction of PHB from C. amphilecti cultures by solubilization in the green solvent methyl levulinate (ML) (2% w/w, 140 °C, 1 h) indicated that the recovery yield and purity of PHB are above 97 and 90% w/w, respectively. The use of ML could be an attractive method for the recovery of PHB when safe and non-toxic solvents are required. [ABSTRACT FROM AUTHOR]

Carnosine (β-alanyl-L-histidine) and its methylated counterpart anserine (β-alanyl-1-methylhistidine) are important functional dipeptides found in various vertebrates' tissues. In this study, we identified the critical parameters of pulsed electric fields (PEF), coupled to mechanical pressing, followed by incubation in water up to 240 min for the extraction of these bioactive dipeptides from chicken meat. We show that PEF improves the kinetics of anserine and carnosine release to water by 7 to 53%, compared to the same water extraction process without PEF when the incubation time is below 120 min. A fractional factorial design showed that the incubation time in the water, after PEF pretreatment, had the most significant effect on dipeptides extraction. The maximum achieved total protein yield was 15.5 mg g fresh weight(FW) -1 after 120 min incubation in water. The maximum carnosine extraction yield was 7.48 mg g FW −1 with a maximum anserine extraction yield of 3.05 mg g FW −1. The specific energy yield of extraction of protein, carnosine, and anserine was 488.16 mg J−1, 39.43 mg J−1, and 131.63 mg J−1 respectively. The developed method is scalable and could be further explored to extract bioactive compounds from animal tissues. • Extraction of functional dipeptides from chicken meat by inducing electroporation. • Pulsed electric field treatments could enhance extraction yields of carnosine and anserine. • Study on the impact of process parameters revealed crucial factors to consider. • Potential for value-addition from animal tissues by low-energy scalable PEF technology [ABSTRACT FROM AUTHOR]

[Display omitted] • Application of extreme halophilic archaea for PHA production. • Utilization of pneumatically agitated reactors for outdoor fermentation. • Application of ultrasonic separation technology for harvesting of archaeal biomass. • Value addition towards a halophilic biorefinery. The present study tested the outdoor cultivation of Haloferax mediterranei for PHA production from green macroalgae Ulva sp. in pneumatically agitated bioreactors and applied ultrasonic separation for enhanced settling of archaeal cells. Scaled-up cultivation (40 L) yielded maximum biomass productivity of 50.1 ± 0.11 mg·L-1·h−1 with a PHA productivity of 27 ± 0.01 mg·L-1·h−1 and conversion yield of 0.107 g PHA per gram Ulva DW. The maximum mass fraction of PHA achieved in biomass was calculated to be 56% w/w. Ultrasonic harvesting of Hfx. mediterranei cells approached 30% removal at energy inputs around 7.8 kWh·m−3, and indicated no significant aggregation enhancement by Ca2+ addition. Molecular weight analysis showed an increase in Polydispersity Index (PDI) when the corresponding air velocities were increased suggesting that the polymer was more homogeneous at lower mixing velocities. The current study demonstrated scalable processes for PHA production using Ulva sp. feedstock providing new technologies for halophilic biorefinery. [ABSTRACT FROM AUTHOR]

Edible green marine macroalgae, especially species of Ulva , can accumulate starch up to 30% of their dry weight; however, its physicochemical, functional, and digestibility properties are still unknown. In this study, we characterized molecular mass distribution, amylose-amylopectin ratio, crystallinity, hydration capacity, viscoelastic and pasting properties, and the digestibility of starch extracted from Ulva ohnoi and compared it to rice and potato starches. Ulva starch had a higher amylose content than rice and potato starches (55.0%, 34.5% and 24.3%, respectively). Ulva starch exhibited higher hydration capacity than rice starch (25.7 g water /g starch and 10.3 g water /g starch respectively), while potato starch exhibited the highest hydration capacity, of 41 g water /g starch , probably mainly due to presence of phosphate groups. Ulva starch had the lowest mass-average molecular weight ((1.17×106 g/mol), compared to rice (4.40×106 g/mol) and potato (5.80×106 g/mol) starches. Ulva starch exhibited the highest G′ and viscosity setback ratio after cooling-induced gelation following gelatinization, probably thanks to its uniquely high amylose content, which led to higher tendency for physical crosslinking by retrogradation. This may also explain the fact that Ulva starch exhibited somewhat lower digestibility after retrogradation, compared to rice and potato starches, which would be advantageous for forming resistant starch serving as a dietary fiber, and lowering glycemic index. The superior gel properties on the one hand and lower digestibility, which would be helpful in tackling obesity & diabetes, on the other hand, make U lva starch a unique and promising new functional food ingredient. [Display omitted] • Ulva ohnoi amylose content: 55% of the starch, more than most terrestrial starches. • Ulva starch exhibited higher hydration capacity than rice starch. • Gelatinized Ulva starch exhibited the highest G′ after cooling-induced gelation. • Ulva starch had somewhat lower digestibility than rice and potato starches. • Lower digestibility may lead to lower glycemic index, advantageous against diabetes. [ABSTRACT FROM AUTHOR]

• Exploring Polyhydroxyalkanoats production by green seaweed associative bacteria. • Ulva sp. hydrolysates as a substrate for PHA production by microbial isolates. • New Cobetia isolates afforded high PHA production, 61% (w/w) This work aimed to isolate a series of bacterial strains associated with the green seaweed Ulva sp. and evaluate their capability to manufacture PHA. The effect of the type of supplemented sugars found to be in macroalgae, on the growth and PHA productivity of the strains was studied. Analysis of the 16S rRNA gene sequence of the isolated strains revealed that the PHA-producing bacteria were phylogenetically related to the genus Cobetia , Bacillus , Pseudoaltermonas and Sulfitobacter, which showed high PHA contents among the isolates. The highest PHA content was observed in the case of Cobetia strain, with up to 61% w/w in the presence of mannitol and 12% w/w on Ulva sp. acid hydrolysate as a substrate. [ABSTRACT FROM AUTHOR]

• Hydrothermal processing of the whole Ulva sp. biomass vs. extracted carbohydrate fractions of starch and cellulose. • Glucose is a major released monosaccharide with hydrothermal deconstruction. • Most of the glucose is released from starch. • Whole biomass hydrolysis preferred for PHA fermentation with Haloferax mediterranei. • The highest ash-free hydrochar yield was from Ulva cellulose. In the fermentation and bioenergy industry, terrestrial biomass is usually fractionated and the collected components, such as starch, are processed separately. Such a separation has not been reported for seaweeds. In this work, the direct hydrothermal processing of the whole green seaweed Ulva sp. biomass is compared to processing of separated starch and cellulose, to find the preferable route for monosaccharide, hydrochar, and polyhydroxyalkanoates (PHA) production. Glucose was the major released monosaccharide. A significant share of the glucose yield comes from the starch fraction. The highest hydrochar yield with the lowest ash content was obtained from the separated cellulose fraction. The highest PHA yield was obtained using a whole Ulva sp. hydrolysate fermentation with Haloferax mediterranei. Economic analysis shows the advantage of direct Ulva sp. biomass fermentation to PHA. The co-production of glucose and hydrochar does not add significant economic benefits to the process under plausible prices of the two outputs. [ABSTRACT FROM AUTHOR]

• SW treatment of Ulva biomass led to the production of hydrochar and phytochemicals. • SW treatment led to the extraction of 84.9% protein from the total Ulva protein. • Ethanol production was optimized with S. cerevisiae and E. coli , in a two-step. • 0.84% of Israel's EEZ can cover all national demand for protein by using Ulva. Marine seaweeds are promising biomass feedstock for the co-production of food, energy and chemicals in a biorefinery. In this study, subcritical water hydrolysis (SWH) was applied to the biomass of green seaweed Ulva sp., fast-growing cosmopolitan seaweed. The SWH was done with seawater at 180 °C and 10.5 bar during 40 min with 8% w/w solid load. This treatment resulted in 211 ± 7 mg of hydrochar g−1 dry weight (DW) of Ulva sp. with higher heating value (HHV) double that of the initial biomass. The liquid fraction content per gram of Ulva DW included 5.2 ± 1.15 mg of 5-HMF; 24.1 ± 2.84 mg total monosaccharides (composed of 14.3 ± 1.78 mg glucose, 5.1 ± 0.41 mg rhamnose, 2.3 ± 0.41 mg fructose, 1 ± 0.06 mg xylose, 0.9 ± 0.08 mg galactose and 0.6 ± 0.11 mg glucuronic acid); 58 ± 11.78 mg protein (corresponding to 84.9 ± 13.2% of the total protein); and free amino acids (3.64 ± 0.07 mg leucine, 2.08 ± 0.13 mg arginine, 1.54 ± 0.01 mg isoleucine and 1.06 ± 0.03 mg alanine). Two-step fermentation optimization was done with Saccharomyces cerevisiae and Escherichia coli in Ulva hydrolysate following the SWH, with ethanol yield of 4.67 ± 0.76 mg g−1 DW Ulva. Based on these process results, some economics and sustainability indicators were estimated for large-scale macroalgae-based biorefinery. The required offshore areas for Ulva cultivation to satisfy the entire national demand in Israel for plant-based protein, char for electricity production (20% blend co-firing with coal), or ethanol for transportation (10% blend in gasoline), are 0.8%, 3.1% and 34.3%, respectively of the Israeli exclusive economic zone in the Mediterranean sea. The total revenue expected for the co-products derived from Ulva sp. via SWH varies between $0.26 and $1.06 kg−1 DW. [ABSTRACT FROM AUTHOR]

The present study analyses the effects of low intensity pulsed electric fields (PEFs), coupled to mechanical press dewatering on meat drying with air convection. Process parameter optimization using Taguchi design showed that the number of pulses had most significant effect on meat dewatering. A maximum effective diffusivity of 2.31 × 10−9 m2 s−1 was observed for PEF assisted drying of chicken meat at 80 °C. An overall energy saving of 933.18 ± 22 J g−1 was observed for drying at 60 °C when the meat was treated with a voltage of 75 V with initial distance between electrodes of 6.917 ± 0.38 mm, pulse length 7 ms, 300 pulses with a frequency of 2 Hz under 125.44 kPa continuous mechanical load. Our study suggests that PEF coupled to mechanical dewatering saves energy in conventional meat drying with air convection. Such a strategy could provide a scalable model for PEF assisted drying of various food products with higher energy efficiency and improved diffusivity. • Utilization of pulsed electric fields to reduce energy consumption for drying of chicken meat with maximum energy savings of 933.18 ± 22 J g−1. • Application of Taguchi methodology for optimization of process parameters. • Effect of various drying temperatures on the water diffusivity with ~40% water removal using PEF treatment. • Sustainable and energy-efficient process for manufacture of dried meat products. Industrial Relevance. Drying is an energy intensive operation that easily accounts for up to 15% of all industrial energy usage, often with relatively low thermal efficiency in the range of 25–50%. In conventional thermal drying methods, flavor, color, and nutritional loss (vitamin degradation and loss of amino acids) occur because of thermal degradation, which decreases the drying rate and rehydration ratio. For this reason, new technologies should be used to obtain better quality dried meat and dried meat products. The present study demonstrates the utility of PEF treatment for drying of food items in an energy efficient manner. The results indicated that PEF could assist in drying by reducing the water content. The process is low energy consuming thereby increasing its utility for a variety of food products. The methods used are scalable and could be used for increased shelf life of various food items. [ABSTRACT FROM AUTHOR]

Optimization of protocols is required for each specific type of biomass processed by electroporation of the cell membrane with high voltage pulsed electric fields (PEF). Such optimization requires convenient and adaptable laboratory systems, which will enable determination of both electrical and mechanical parameters for successful electroporation and fractionation. In this work, we report on a laboratory PEF system consisting of a high voltage generator with a novel asymmetric voltage multiplying architecture and a treatment chamber with sliding electrodes. The system allows applying pulses of up to 4 kV and 1 kA with a pulse duration between 1 μs and 100 μs. The allowable energy dissipated per pulse on electroporated biomass is determined by the conditions for cooling the biomass in the electroporation cell. The device was tested on highly conductive green macroalgae from Ulva sp., a promising but challenging feedstock for the biorefinery. Successful electroporation was confirmed with bioimpedance measurements. Seaweed biomass is an emerging feedstock for biorefineries with already 30 million tons per year of global industrial production. However, most of the biomass produced today is lost. Pulsed electric field (PEF) extraction could allow saving energy on biomass drying, deashing and it could allow extracting various organic compounds. However, the parameters needed to seaweed biomass treatment with PEF are not known and will differ from species to species. Furthermore, very high salt content challenges most of the available laboratory PEF devices, limiting the ability for parameters optimization in the lab. The developed laboratory scale PEF system coupled to bioimpedance measurement provides a necessary set of tools and methods for PEF parameters optimization required for process scale-up. • Pulsed electric field generator with gravitation press electrodes was developed for seaweed biomass electroporation. • Asymmetric voltage multiplying architecture allows to control the voltage of each pulse. • PEF parameters 4 kV, 1 kA, 1–100 μs duration and total power dissipation of 20 W • Macroalgae Ulva sp. was treated with 124 ± 12 V mm−1, pulse duration 50 μs, pulse number 50, frequency 3 Hz. • Electroporation of the biomass was confirmed with bioimpedance measurements. [ABSTRACT FROM AUTHOR]

• Green macroalgae Ulva sp. was cultivated 15 km offshore. • A positive growth rate of offshore cultivated Ulva sp. was measured during 7 months of cultivation. • A positive yield was measured during 7 months of cultivation. • Pulsed electric field dewatering of Ulva sp. saves energy on convective air drying. Offshore macroalgae biomass production is a promising, yet challenging, pathway to provide feedstock for biorefineries. In this work, a device and a process for dewatering offshore grown biomass of the green macroalgae Ulva sp. using high-voltage pulsed electric fields (PEF) was developed. Ulva sp. was cultivated attached to fish cages 15 km offshore. Increasing the applied voltage from 250 V to 500 V and invested PEF energy from 9.3 ± 0.4 J g−1 FW to 54.6 ± 0.2Jg−1 FW increased the extracted water from 0.033 ± 0.006 g Water g−1 FW to 0.150 ± 0.031 g Water g−1 FW. The energy consumption to achieve similar moisture content with air convection drying was lower by 78.73 ± 10.41 (JgFW−1) for 250 V and 339.31 ± 48.01 (JgFW−1) for 500 V, pulse duration 50 µs, pulse number 50, pulse repetition frequency 3 Hz. PEF leads to biomass compression of 8.45 ± 1.72% for 250 V protocol and 25.66 ± 2.53% for 500 V protocol. In addition, PEF leads to the reduction of water diffusivity of 18–19% in the treated biomass, reducing air drying kinetics. [ABSTRACT FROM AUTHOR]

• The estimated U-factor of the studied algae window profile was 4.9 W m−2 K−1, VT and SHGC differ significantly according to the studied microalgae specie and concentration in the window system. • The maximum available energy saving of the studied algae window significantly differs according to the façade orientation and reached up to 20 kWh m−2 year−1 in the South façade. • Algae concentration, window size and the combination factor of algae concentration with window size were found to be statistically significant in affecting the energetic impact of the algae window, for each façade orientation. The present study focused on analyzing the potential impact of incorporating living microalgae to the built facades, Algae Window, on the energy consumption reduction of a building. Two microalgae species of Chlamydomonas reinhardtii and of Chlorella vulgaris were cultivated and the impacts cells density were studied on the light penetration and heat transfer. The experimentally measured impacts of the two studied microalgae species were used to calculate the U-factor (Thermal conductance), VT (Visible Transmittance) and SHGC (Solar Heat Gain Coefficient) of the Algae Window. Based on the empirical results, the impact of the algae window on the energy consumption was estimated by extensive simulation study within an office space in the LEED accredited Porter building in Tel-Aviv University, Israel. The results show that incorporation of the microalgae into the windows has the potential to improve the energy efficiency in the studied building under the conditions of the Mediterranean climate. The impact of the algae window on the energy consumption was estimated in comparison to single glazing and to double glazing, and was found to differ significantly according to the facade orientation in both microalgae species; at maximum concentrations in the algae window as compared to single glazing window, the energy saving reached up to 20 KWh m−2 year−1 in South, 8 KWh m−2 year−1 in East, 14 KWh m−2 year−1 in West, and energy increase up to 18 KWh m−2 year−1 in North. Three factors were found to explain the variance in the energy saving performance of the Algae Window, namely, the algae concentration, the window size and the combination factor of the algae concentration with the window size that yielded the largest effect on decreasing the energy consumption. This study suggests that incorporating microalgae cultivation in building windows can provide energy saving to the building and addresses the main design factors that can effect on the savings as well as on other energetic aspects involved in the system such as energy production from algal biomass that has multiple applications in the urban environment. [ABSTRACT FROM AUTHOR]