Biofuels from algae Research Papers (original) (raw)

2025, Natural Resources

Cellulases and hemicellulases are the main industrial sources from different microorganisms used to depolymerise plant biomass to simple sugars that are converted to chemical intermediates and biofuels, such as ethanol. Cellulases are formed adaptively, and several positive (xyr1, Ace2, HAP2/3/5) and negative (Ace1, Cre1) components involved in this regulation are now known. In this review, we summarise current knowledge about how cellulase biosynthesis is regulated, and outline recent approaches and suitable strategies for facilitating the targeted improvement of cellulase production by genetic engineering. Trichoderma reesei is the preferred organism for producing industrial cellulases. However, a more efficient heterologous expression system for enzymes from different organism is needed to further improve its cellulase mixture. In addition those optimizations of the promoter and linker for hybrid genes can dramatically improve the efficiency of heterologous expression of cellulase genes.

2025, Topics in Catalysis

An overview is given of newly developed Lewis or Brønsted acid and base catalysts for esterification, transesterification and ester interchange reactions. The most relevant applications of these catalysts and reactions in the domain of... more

2025

This study assesses the sustainability of bioethanol production from multiple agricultural feedstocks, including corn stover, wheat straw, and rice husk, using a life cycle assessment (LCA) method. The process focuses on converting lignocellulose biomass into bioethanol through advanced biotechnology, enriching energy security and supporting sustainable development in Pakistan. The process includes various stages of feedstock utilization, including cultivation, harvesting, transportation, preprocessing, and conversion, eventually yielding 1 kg of bioethanol with different inventories for each of the three feedstocks. A comparative analysis of the three feedstocks reveals that the wheat straw showed the highest environmental impacts, while rice husk exhibits the least environmental impacts and emerges as a more sustainable and viable option for bioethanol production. The economic assessment revealed the feasibility of bioethanol production, achieving a daily revenue of 9600andamonthlyincomeof9600 and a monthly income of 9600andamonthlyincomeof211,200, based on 22 working days in a single 8 h shift. The total initial capital investment cost was estimated at 478,515,whileoperationalcostswerecalculatedat478,515, while operational costs were calculated at 478,515,whileoperationalcostswerecalculatedat225,921. The external cost of the plant was evaluated at $14.23. Transitioning from grid-mix to renewable energy, such as photovoltaic systems, showed a reduction among three feedstocks. Therefore, bioethanol production not only addresses waste management challenges but also contributes to waste-to-energy conversion and renewable energy generation, aligning with public health goals and sustainable development. The findings highlight the potential of bioethanol production as a strategic solution to manage agricultural waste sustainably and reduce greenhouse gas emissions.

2025, High Technology Letters

Alternative fuels are one of the most desirable issues in the present world. Vegetable oils play a significant role in this aspect and among the vegetable oils, Kusum oil (Schleicheraoleosa)is one of the promising feedstocksfor the production of alternative fuels like biodiesel. In the present study, biodiesel is produced from Kusum oil through a transesterification reaction with methanol (1:4 molar ratio of Kusum oil and methanol) at a temperature of 65 0 C with a mixing intensity of 575 rpm for 10 hrs. The reaction occurs in the presence of 8% biological catalyst Candida antarctica which can be recycled further. The characteristics of biodiesel from Kusum oil arecompared with diesel fuel and it shows expected outcomes.

2025

Abstract-- Eutrophication caused by the imbalance of chemicals, from disposed wastes in lakes and ponds, along with the presence of sunlight gives a boost to the growth of microalgae in the lake. Algae farming can be carried out by creating open ponds or photo bioreactor (PBR). On further treatment, the harvested algae can be converted into biodiesel. Such a productive result to waste water treatment can be carried out at varied locations where the optimum operating conditions for micro algae farming are satisfied. I.

2025, Renewable & Sustainable Energy Reviews

Microalgae are fast growing organisms and have the ability to accumulate lipid, which can be converted to biofuels. Here, we review specific growth rate, population productivity, and lipid productivity based on 192 publications of the marine microalgae Nannochloropsis. Specific growth rate was reported by thirty publications often using exponential growth equations, and fourteen publications stated biomass productivity. However, direct comparison among productivity estimates is impossible due to differences in calculations or omission of equations. Less than 5% of the publications directly reported lipid productivity, the key parameter for biofuels. We extracted growth data from 30 publications using Plot Digitizer software and tested best fit with exponential and logistic equations. The logistic equation often represents growth data better than the exponential one. Furthermore, we argue that maximum sustainable yield (MSY) is a more useful measure for harvest rates than specific growth rates. Interestingly, MSY displayed closer linear relationships with carrying capacity measures (r 2 ¼0.780, po 0.001 and r 2 ¼0.552, po 0.001 for algae density and biomass, respectively) than growth rate (r 2 ¼ 0.297, po 0.001 and r 2 ¼0.095, p¼ 0.090). We propose to apply concepts of logistic growth, carrying capacity and MSY calculations to estimates of maximum lipid productivity, similar to commonly used density and biomass calculations.

2025, Biomass-derived graphene and nanostructured carbons: A review for electrochemical applications

Carbon is the most promising material today. Biomass-residues are carbon-rich and have the possibility to replace obsolete, expensive and pollutant raw sources. For instance, graphene-like materials have attracted a powerful attention since its discovery. The varied textural properties, porosity, surface chemical functionality and conductivity make these biomass-derived materials ubiquitous to be used in solar cells, supercapacitors, and electrochemical sensors, among many other applications. The objective of the review is to summarize the advances in energy conversion, storage, and electrochemical sensing technologies using nanocarbons prepared from biomass. In this work we intend to correlate the nature of the graphene-or carbon-like material and its use in the different electrochemical applications mentioned. A discussion on the properties that define the effectiveness of a supercapacitor in energy storage is also proposed. The projections and future challenges in solar cells, supercapacitors and electrochemical sensors technology are also presented.

2025, Energy

Seaweed may be a source of third generation gaseous biofuel, in the form of biomethane. The scientific literature is sparse on the relative suitability of different varieties of seaweed to produce biomethane. This paper assesses the BMP (biochemical methane potential), ultimate analysis and theoretical yields of ten species of seaweed which may be found in commercial quantities around the coastline of Ireland. Saccharina latissima reported the highest BMP yield (ca. 342 L CH 4 kg VS À1 ). S. latissima if farmed, may produce 10,250 m 3 CH 4 ha À1 yr À1 (365 GJ ha À1 yr À1 ) which is in excess of all land based liquid biofuel systems.

2025

This paper explores the multifaceted challenges and realities of the global energy transition, focusing on the interplay between renewable energy sources and fossil fuels. While renewable energy technologies such as solar and wind power offer promising solutions for reducing carbon emissions, their intermittency and reliability issues present significant challenges in ensuring a consistent power supply. Using Germany's energy grid as a case study, the paper highlights how the integration of solar and wind power requires careful management to address gaps in energy availability. Additionally, the paper discusses the ongoing growth of fossil fuel production, challenging the notion of an “energy transition” and suggesting that the world is experiencing an “energy addition,” where fossil fuel production continues to rise alongside renewable energy adoption. The continued relevance of fossil fuels, including propane for heating and cooking, is underscored, particularly in remote regions and underdeveloped areas. Ultimately, this paper advocates for a balanced approach to energy policy, recognizing the ongoing importance of fossil fuels while promoting the advancement and integration of renewable technologies to achieve long-term energy sustainability and security.

2025

Present industrialization and global mobility era is an energy intensive period of the human history with an ever increasing energy demand. Unfortunately, fossil fuels are no more sustainable due to growing gap between the demand and supply. Biofuels are considered as promising alternative liquid fuels in recent global energy scenario. Food crops and ligno-cellulosic plant biomass have been widely studied as an alternative feedstock for biofuels production. After decades of research, the competition of fuel with food and recalcitrant nature of plant biomass, these feed stocks are losing their popularity. Marine macroalgae have come forward as another potential feedstock for biofuels production. Marine algae have several advantages over the traditional energy crops including absence of lignin, higher growth rates and no competition with human food. Moreover, along with several environmental benefits, they can be grown using saline and waste water and have higher abilities to sequester the atmospheric CO2 than traditional energy crops. Although there are several challenges associated with the algal biomass conversion to bioenergy yet these problems can be overcome using integrated biorefinery approach.

2025, Materials Science for Energy Technologies

Cultivation of microalgae in wastewaters and co-production of algal biomass have been considered as a sustainable approach for wastewater treatment. To achieve desirable biomass productivity and pollutants removal efficiencies, microalgal strain, cultivation mode and culturing conditions should be optimized. This was firstly aimed at examining growth characteristics of Chlorella variabilis TH03 strain under phototrophic, heterotrophic and mixtrophic cultivations using BG-11 medium as the sole of nutrient source. Secondly, the culturing variables such as aeration rate, percent dilution, N/P ratio and supplemented CO 2 concentration were optimized to maximize biomass production and nutrient removal efficiencies of the algal strain in domestic wastewater. Thirdly, growth and nutrient removal capability of C. variabilis TH03 were investigated in an outdoor reactor system using domestic wastewater as a culture medium. Data showed that C. variabilis TH03 grew well under phototrophic and mixtrophic conditions but completely inhibited under heterotrophic conditions. In mixtrophic conditions, optimal aeration rate, percent dilution, N/P ratio and supplemented CO 2 concentration achieved for the maximum growth and nutrient removal efficiencies were 0.2 vvm, no dilution, N/P = 15:1 and 15% CO 2 , respectively. Moreover, C. variabilis TH03 also exhibited an outstanding growth and nutrient removal capability in the outdoor reactor system, reaching areal biomass productivity of 39.5 g/m 2 •day. Pollutants including COD, TN and TP were removed at efficiencies of 73.9, 97.1 and 99.8%, respectively. Nutrient levels in the effluent dropped below those required by the national technical regulation on domestic wastewater QCVN 14:2008/BTNM and QCVN 14-MT: 2015/BTNMT. The obtained results are useful for further study in large scale cultivation of C. variabilis TH03 for the production of high volume and low price biomass, helping to obtain returns from treatment of the waste stream, which is currently considered as a major source of water pollution in Vietnam.

2025, Chemical engineering transactions

Palm oil production has become a major contributor to the economy of several tropical countries where palm oil trees can be grown commercially, particularly due to its high productivity and capability to yield more oil from less land area. Palm oil milling activities generate wastewater that is highly polluted and requires to be treated before it can be discharged into the environment. The wastewater generated from the milling activities is defined as palm oil mill effluent (POME). Studies have shown that algae can be grown using wastewater. The utilisation of algae for POME treatment coupled with biogas facilities in the palm oil mill can simultaneously remediate the wastewater and reduce the cost for nutrient and freshwater supplies required for algae growth. This paper investigates the techno-economic potentials of an integrated algae-based bio- refinery with palm oil mill. The proposed superstructure for the integrated bio-refinery includes carbon sequestration, algae growth wit...

2025

Using nanoadditives in biohydrogen production can be considered an optimal solution for existing challenges. Nanoparticles (NPs), affect the growth of microorganisms, intracellular electron transfers and the activity of metalloenzymes. The main research gap is to analyze and evaluate the effect of different types of NPs in several studies. The primary purpose of this study is to cover the research gap, by exploring the research databases, employing a complete list of search items followed by PRISMA guidelines. The taxonomy of the present study can cover these weaknesses and can successfully complement other studies. Evaluations have been conducted by the findings of the identified articles during the PRISMA guidelines. We also applied a feature selection technique to find the most important factor affecting the biohydrogen production yield. Accordingly, the additive values with the Relief feature selection score of 0.47±0.17 provided the highest impact on the biohydrogen production yield, followed by PH, with a score of 0.36±0.13. Finally, results showed that Fe-based additives boosted the catalytic mechanisms and metabolisms in all of the substrates. Conversely, Carbon-based additives enhanced glucose degradation in the substrates, and Biochar improved biological activity. The type of substrates and the number of NPs in each substrate are different. This study presents comparable results for each finding, based on the evidence. The main findings of this review can be of valuable help in the initial development of integrated additives, with different mechanisms of action.

2025, Economic Effects of Biofuel Production

2024, Catalysts

In this research, core-shell structured Fe 3 O 4 @MIL-100(Fe) composites were prepared by coating Fe 3 O 4 magnetite with porous MIL-100(Fe) metal-organic framework (MOF) material, which were then utilized as magnetic supports for the covalent immobilization of the lipase from Candida rugosa through amide linkages. By using the carbodiimide/hydroxysulfosuccinimide (EDC/NHS) activation strategy, the lipase immobilization efficiency could reach 83.1%, with an activity recovery of 63.5%. The magnetic Fe 3 O 4 @MIL-100(Fe) composite and immobilized lipase were characterized by several techniques. The characterization results showed that the Fe 3 O 4 core was coated with MIL-100(Fe) shell with the formation of perfect core-shell structured composites, and moreover, the lipase was covalently tethered on the magnetic carrier. The immobilized lipase displayed a strong magnetic response and could be facilely separated by an external magnetic field. With this magnetic biocatalyst, the maximum biodiesel conversion attained 92.3% at a methanol/oil molar ratio of 4:1, with a three-step methanol addition manner, and a reaction temperature of 40 • C. Moreover, the biocatalyst prepared in the present study was recycled easily by magnetic separation without significant mass loss, and displayed 83.6% of its initial activity as it was reused for five runs, thus allowing its potential application for the cleaner production of biodiesel.

2024, Bioresource Technology

In this study, mixed culture (microalgae:activated sludge) of a photobioreactor (PBR) were investigated at different inoculation ratios (1:0, 9:1, 3:1, 1:1, 0:1 wt/wt). This work was not only to determine the optimal ratio for pollutant remediation and biomass production but also to explore the role of microorganisms in the co-culture system. The results showed high total biomass concentrations were obtained from 1:0 and 3:1 ratio being values of 1.06, 1.12 g L-1 , respectively. Microalgae played a dominant role in nitrogen removal via biological assimilation while activated sludge was responsible for improving COD removal. Compared with the single culture of microalgae, the symbiosis between microalgae and bacteria occurred at 3:1 and 1:1 ratio facilitated a higher COD removal by 37.5-45.7 %. In general, combined assessment based on treatment performance and biomass productivity facilitated to select an optimal ratio of 3:1 for the operation of the co-culture PBR.

2024

Healthcare resources have changed fundamentally compared to decades ago. Modern
bio-food products and sustainable solutions for their production have increased the attention of
researchers, taking into account the current level of pollution of the earth and atmosphere along with
modern technologies applied to processed foods. Therefore, this review aims to highlight: (1) the
impact and relationship between the physiological parameters of the atmosphere, solar radiation
and soil, (in terms of their composition and stages of formation and organization) along with the
evolution to modern life; (2) the environmental impacts on algae, living organisms, food, and human
health and sustainability. In addition, we address the significant impact of algae as a sustainable
resource in reducing environmental pollution contributing to a healthier life.

2024, Agricultural Biotechnology Journal

Objectives Antibiotic-resistant bacteria have become a worldwide concern due to the unintentional use of antibiotics, which has resulted in bacterial strains resistant to many or all available antibiotics. The primary and secondary... more

2024

This paper will introduce a research regarding microalgae biomass as an environmentally and sustainably alternative biodiesel raw material. The purpose of the research is to compare all production cost variables between microalgae and oil palm biodiesel using production process cycle analysis system of extended life cycle analysis (extended LCA). The use of extended LCA system could possibly accommodate all environmental commodity variables on biodiesel production so that the potential microalgae biomass which is a renewable, low land use and environmentally sustainable product could be promoted. Values of environmental commodity variables are estimated by employing a willingness to pay (WTP) approach that is referred to the calculation of Environmental Priority Strategy (EPS) Software. The result research shows that there is an increase of biodiesel production cost of microalgae and oil palm after the inclusion of their externality variables cost. The biggest biodiesel production c...

2024

The fascinating world of microscopic life unveils a captivating spectacle as bacteria effortlessly maneuver through their surroundings with astonishing accuracy, guided by the intricate mechanism of chemotaxis. This review explores the complex mechanisms behind this behavior, analyzing the flagellum as the driving force and unraveling the intricate signaling pathways that govern its movement. We delve into the hidden costs and benefits of this intricate skill, analyzing its potential to propagate antibiotic resistance gene while shedding light on its vital role in plant colonization and beneficial symbiosis. We explore the realm of human intervention, considering strategies to manipulate bacterial chemotaxis for various applications, including nutrient cycling, algal bloom and biofilm formation. This review explores the wide range of applications for bacterial capabilities, from targeted drug delivery in medicine to bioremediation and disease control in the environment. Ultimately, through unraveling the intricacies of bacterial movement, we can enhance our comprehension of the intricate web of life on our planet. This knowledge opens up avenues for progress in fields such as medicine, agriculture, and environmental conservation.

2024, Journal of Applied Life Sciences International

The depletion of fossil fuels and increased atmospheric CO2 levels have precipitated a global energy and environmental crisis. The cultivation of microalgae offers a viable remedy by utilizing solar energy and assimilating CO2 for biofuel production via photosynthesis. Microalgae demonstrate rapid growth in diverse environments, rendering them a dependable biomass source for large-scale biofuel generation. Furthermore, their biofuel production can be tailored through the manipulation of growth conditions or genetic engineering. This review aims to highlight the variety of biofuels produced from microalgae and the methodologies to optimize their yield. This review also explores the economic implications of algal biofuel production in both open ponds and closed photobioreactors. Various strategies for the photo-production of biohydrogen utilizing the hydrogenase enzyme from green algae are investigated. Additionally, certain microalgae species are recognized for their potential as biodiesel sources due to their high lipid content. The lipid profiles of leading oil-producing algal strains under optimal conditions are assessed. This review further examines the potential of microalgae in synthesizing petroleum-based chemicals and in generating bioethanol and biogas from algal biomass.

2024, Marine Drugs

The marine microalga Nannochloropsis oculata has garnered significant interest as a potential source of lipids, both for biofuel and nutrition, containing significant amounts of C16:0, C16:1, and C20:5, n-3 (EPA) fatty acids (FA). Growth parameters such as temperature, pH, light intensity, and nutrient availability play a crucial role in the fatty acid profile of microalgae, with N. oculata being no exception. This study aims to identify key variables for the FA profile of N. oculata grown autotrophically. To that end, the most relevant literature data were gathered and combined with our previous work as well as with novel experimental data, with 121 observations in total. The examined variables were the percentages of C14:0, C16:0, C16:1, C18:1, C18:2, and C20:5, n-3 in total FAs, their respective ratios to C16:0, and the respective content of biomass in those fatty acids in terms of ash free dry weight. Many potential predictor variables were collected, while dummy variables were ...

2024, GCB Bioenergy

The transition to biofuels as viable alternatives to fossil fuels is increasingly critical, given the rising demand for sustainable energy. However, biofuel production is hindered by challenges such as feedstock scarcity, elevated production costs, and environmental impacts. Nanotechnology has the potential to significantly improve the efficiency and durability of biofuel production processes, thereby overcoming these challenges. Although there has been significant research on using nanomaterials in biofuel production, there needs to be more emphasis on understanding and addressing the difficulties of integrating these materials and developing strategies to overcome them. This review systematically examines the role of nanotechnology in various biofuel production pathways, including biodiesel, biogas, bioethanol, biohydrogen, hydrotreated vegetable oils, and Fischer-Tropsch synthesis. We discuss how nanomaterials improve key aspects of biofuel production, such as catalysis, microbial conversion, biomass pretreatment, and separation. Despite these advancements, nanotechnology has challenges, including nanoparticle toxicity, increased operational costs, and technical limitations. We propose potential solutions to these issues, emphasizing the need for interdisciplinary collaboration and innovative approaches. By effectively integrating nanotechnology into biofuel production, the energy sector can move toward a more sustainable and environmentally friendly future.

2024, Development of a Hybrid Methodology for Synthesis of Biofuels Production Processes Based On Optimization of Superstructures

Biofuels can be obtained using different processing routes and raw materials, so there are infinite combinations of possible topologies for raw material processing; it is desirable to develop a methodology for evaluation of different combinations in order to select the pathway that best accomplish a specific criterion. In this paper, the authors developed a hybrid methodology for the synthesis of biofuel production processes, based on a branch of available products and intermediates, the establishment of a superstructure with technologies and chemical species involved, mathematical optimization of production routes and depth assessment of the most promising alternatives. As a case of study, the methodology is applied in the synthesis of a process of production of biofuels from wastewater. The results showed correspondence between intermediate and final products for biodiesel and hydrogen, and the superstructure was constructed based biodiesel as main product. The optimization of the superstructure showed that the most promising route is through hydrothermal liquefaction of organic slurry and hydroprocessing of biocrude, with a maximum product yield of 0.61 tonnes of biodiesel/tonne of biomass.

2024, 3rd International Student Biotechnology Congress

Microalgae, the world’s largest group of photosynthetic organisms, convert atmospheric CO2 to polar and neutral lipids using sunlight, which after esterification can be utilized for biodiesel production. This article represents possible production of valuable microalgae from wastewater that can be used for biodiesel production. In this study, dominant species of algae in the wastewater from aerobic and anaerobic sectors of Parkandabad wastewater treatment plant were determined and algal growth curve, lipid content as well as biomass and lipid productivities for aerobic and anaerobic samples were investigated. The lipid contents of aerobic and anaerobic samples were 37.5% and 20% glipid. gbiomass-1, respectively. Thus wastewater can be efficiently utilized as a suitable source of biodiesel production.

2024, The 10th International Chemical Engineering Congress & Exhibition (IChEC 2018)

Microalgae have been proposed as a potential source for biodiesel production. The main objective of this study was to screen appropriate microalgae strains from wastewater for biodiesel production. In the present study, a number of algal strains grown in wastewater extracted from aerated and facultative lagoons of Parkandabad wastewater treatment plant, were isolated and four different strains of Chlorella sp. (A-Ch1, A-Ch2, F-Ch3, and F-Ch4) were identified based on morphological characteristics. Samples from aerated (A-R), facultative (F-R), and the four isolated strains were inoculated in BG-11 medium and growth curve, lipid content, biomass and lipid productivities of each experiment were investigated. The cultivation of A-R and F-R samples led to lipid contents of 16.6% and 12.2%, respectively with moderate amount of biomass dry weights. The strains of A-Ch2, F-Ch3, and F-Ch4 could accumulate relatively high lipid contents of 35.5%, 26.3%, and 38.2%, respectively that resulted in high lipid productivities. Moreover, F-Ch4 had the highest biomass and lipid productivities of 0.24 g.L-1.day-1 and 91.96 mg.L-1.day-1 among the strains, respectively. Therefore, the urban wastewater can be utilized as a suitable feedstock for biodiesel production because of the presence of microalgal strains with high lipid content and productivity.

2024, Biochemical Engineering Journal

Microalgae, the world’s largest group of photosynthetic organisms, convert atmospheric CO2 to polar and neutral lipids using sunlight, which after esterification can be utilized for biodiesel production. In the present study, a fully compartmentalized metabolic network was developed to describe the metabolism of Chlorella vulgaris based on known enzymatic reactions and typical metabolic pathways of green algae. Flux balance analysis was employed to optimize the specific growth rate and the lipid production rate using measured exchange fluxes of the metabolites. The experimental data for batch and fed batch algal fermentation systems acquired from the literature were used to validate the accuracy of the pseudo- steady state model. The physiological pathways of the microalgae for lipid biosynthesis were identified. The simulation revealed that the microalgae would be able to produce higher levels of lipid content (43.6%) during N-starvation cultivation under 100 μmolm−2 s−1 light
intensity, 0.25 vvm aeration with 2% (v/v) CO2, 2 mg L−1 PO4-P, and 5 mg L−1 NO3-N. Sensitivity analysis showed that CO2, light energy, O2, and nitrate were the most important factors affecting the lipid production at
N-deficient conditions. The findings consequential for manipulation of the metabolism of the microalgae with optimal activity.

2024

The paper summarizes the Space Technology Department at the Institute of Aviation goals for small spacecraft propulsion technology and link them to areas of propulsion research in Poland in general at the nearest future. A brief review of currently being investigated issue in the newly opened laboratory is presented as current and near term research, focused specifically on: concentrated solutions of H2O2 (stabilized and HTP - High Test Peroxide class) preparation, its long term storage possibilities, catalytic decomposition, “drop tests” for fuel ignition investigation, its use as “green” monopropellant or in hybrid rocket motors as the oxidant. By employing catalytic decomposition of HTP, auto-ignition of the solid fuel in a hybrid rocket is possible. When HTP is properly decomposed, the decomposition products alone release enough heat and the gases have suitable temperature (even over 700°C, depending on the concentration of the solution of peroxide) to provide efficient thrust. ...

2024

Marine diatoms have recently gained much attention as they are expected to be a promising resource for sustainable production of bioactive compounds such as carotenoids and biofuels as a future clean energy solution. To develop photosynthetic cell factories, it is important to improve diatoms for value-added products. In this study, we utilized UVC radiation to induce mutations in the marine diatom Phaeodactylum tricornutum and screened strains with enhanced accumulation of neutral lipids and carotenoids. Adaptive laboratory evolution (ALE) was also used in parallel to develop altered phenotypic and biological functions in P. tricornutum and it was reported for the first time that ALE was successfully applied on diatoms for the enhancement of growth performance and productivity OPEN ACCESS Mar. Drugs 2015, 13 6139 of value-added carotenoids to date. Liquid chromatography-mass spectrometry (LC-MS) was utilized to study the composition of major pigments in the wild type P. tricornutum, UV mutants and ALE strains. UVC radiated strains exhibited higher accumulation of fucoxanthin as well as neutral lipids compared to their wild type counterpart. In addition to UV mutagenesis, P. tricornutum strains developed by ALE also yielded enhanced biomass production and fucoxanthin accumulation under combined red and blue light. In short, both UV mutagenesis and ALE appeared as an effective approach to developing desired phenotypes in the marine diatoms via electromagnetic radiation-induced oxidative stress.

2024, Biofuels, Bioproducts and Biorefining (Biofpr)

This article aims to review the various techniques used to produce diesel from lignocellulosic biomass. Data were collected using the Web of Science database to identify trends, barriers, and prospects associated with the alternative methods used. The analysis reviewed 359 papers published between 2006 and 2021, focusing on three key areas: biomass pretreatment, biomass conversion, and biorefining. Pretreatment technologies require extensive research to reduce excessive energy and reagent consumption, thereby reducing overall costs. Fast pyrolysis and lipid-producing microorganisms have been shown to be the most promising conversion routes due to their versatility in utilizing different lignocellulosic residues and producing a wide range of marketable co-products. The most widely used method used for refining is hydroprocessing coupled with catalysts, with the objective of improving biooil quality. Two of the main challenges are the excessive cost of the overall process and the limitations imposed by the technology. These limitations require processing optimization to achieve sustainable production and valuable co-products. The growth of lignocellulosic diesel production will depend on the integration with other biodiesel and biofuel production processes by the optimization of new processes and the generation of new bioproducts to increase efficiency and reduce costs for commercial viability.

2024, Lusitano Caballero Y Verso

Data centers play a crucial role in the quickly changing digital era. These huge facilities house the fundamental infrastructure of our contemporary data-centric existence, encompassing everything from online social interactions to... more

2024, Marine Drugs

2024, Natural Resources

2024, ALGAE TORCH INFORME

2024, International Journal of Innovative Research in Technology

The quantity of crude oil is continuously declining, which forces researchers to create new sustainable alternative fuels, particularly biofuels. The project's main aim is to optimize the diesel engine operation on biodiesel concerning performance and emission and to find optimum engine parameters using the hybrid AHP-Topis method. In direct-injection (DI) diesel engines, algae methyl esters are used as biodiesel. The general best biodiesel mixture AME20 (80% diesel and 20% algae methyl esters) is used. The engine injection pressure was varied from 200 bar to 240 bar in 20-bar increments. The outcomes demonstrated that AME20 injection pressure adjustment enhanced emissions and diesel engine performance. Algal oil is obtained from the microalga Scenedesmus obliquus. A 20% biodiesel blend was created. The fatty acid composition of S. obliquus affects its fuel properties. Blend20 is similar to diesel oil in terms of its chemical and physical characteristics. A study was done on the performance metrics and exhaust emissions of a diesel engine burning diesel fuel and biodiesel blends. The biodiesel blend showed improved thermal efficiency, reduced exhaust gas temperature, and decreased specific fuel consumption. B20 produced fewer gas emissions than biodiesel. In this paper, compression ratio (CR) and injection parameters such as injection time (IT) and injection pressure (IP) are used to determine the performance and emissions of DI diesel engines using biodiesel (0%, 50%, and 100%).

2024

Los sistemas desarrollados para el cultivo de las microalgas pueden clasificarse en dos grandes grupos, en funcion de la forma de desarrollo de las poblaciones algales: cultivos en suspension y cultivos inmovilizados. A su vez, ambos sistemas de cultivo pueden ser abiertos o cerrados, segun que las microalgas y el medio de cultivo esten en contacto directo con el aire atmosferico o no. Los cultivos de microalgas inmovilizadas en una superficie que actua de soporte, forman un 'biofilm' continuo sobre dicha superficie formando un ecosistema especifico de agregacion denominado 'biofilm', normalmente constituido por varias especies, incluyendo bacterias, aunque puede haber alguna predominante. Las principales ventajas que tienen los fotobior reactores de biofilm sobre los de celulas suspendidas son: a) Facilidad para la cosecha, b) Mayor concentracion por unidad de volumen de medio, c) reduccion o ausencia de celulas en el efluente, d) reduccion en la necesidad de energi...

2024, Sustainability

Environmental pollution caused by conventional petro-diesel initiates at time of crude oil extraction and continues until its consumption. The resulting emission of poisonous gases during the combustion of petroleum-based fuel has worsened the greenhouse effect and global warming. Moreover, exhaustion of finite fossil fuels due to extensive exploitation has made the search for renewable resources indispensable. In light of this, biodiesel is a best possible substitute for the regular petro-diesel as it is eco-friendly, renewable, and economically viable. For effective biodiesel synthesis, the selection of potential feedstock and choice of efficient catalyst is the most important criteria. The main objective of this bibliographical review is to highlight vital role of different catalytic systems acting on variable feedstock and diverse methods for catalysis of biodiesel synthesis reactions. This paper further explores the effects of optimized reaction parameters, modification in chem...

2024, Revista Tecnología Química

Nowadays marine and coastal ecosystems are threatened by the invasion of harmful algal species. The solution to this situation should be aimed at the integral use of this biomass. The drying process has a decisive impact on the quality of the resulting raw material and the cost of any derived by-products. For this reason, the objective of this research is to evaluate the drying process of macroalgae: Sargassum fluitans, Ulva lactuca and Chaetomorpha cf. gracilis, using a solar dryer designed for this purpose. The drying process was evaluated at a temperature of 60°C. The results obtained reported that dehydration in the oven lasted less than 2 hours, while in the solar dryer values higher than those achieved in the oven were recorded. The first derivative analysis shows that the highest peak of moisture loss is around 80 % and is reached in the first 15 min in the electric stove. However, in solar drying it was recorded around 45 min. The results obtained in the drying process were adjusted to a polynomial model with a determination coefficient of 99,13 %.

2024, Energy Conversion and Management

Brown seaweed may be an option as a feedstock for gaseous biofuel production. This paper proposed a detailed study on the impacts of various segments of seaweed thalli on the biomethane production. Ascophyllum nodosum, Laminaria digitata, Laminaria hyperborea, Saccharina latissima and Saccorhiza polyschides have shown significant variation in proximate, ultimate and biochemical composition in various segments of their thalli. The highest biomethane potential of 286 L CH 4 kg VS −1 was recorded from the stipe of L. digitata, whereas the lowest value of 118 L CH 4 kg VS −1 was obtained from the holdfast of L. hyperborean. Due to the accumulated salt in the holdfast, the biomethane performance was reduced compared with the frond and stipe. The specific yield per fresh weight of seaweed was measured in the range of 10 to 32 m 3 CH 4 t −1 wwt. Considering the dominant role of fresh thallus, the frond was the most significant part for seaweed biogas production.

2024, Energy

Pre-treatment can enhance anaerobic digestion of seaweed; however, seasonal variation in the biochemical composition of seaweed has a significant impact on the pre-treatment effect. In this study, various pre-treatments were employed for the brown seaweed Laminaria digitata harvested in March (with high ash content and low carbon to nitrogen (C:N) ratio) and September (with low ash content and high C:N ratio). Washing of L. digitata harvested in March with hot water (defined as 40 °C) removed 54% of the ash and improved the volatile solids (VS) content by 31% leading to an improved biomethane yield of 282 L CH 4 kg VS-1. This pre-treatment affected a 16% increase in biodegradability, reduced salt accumulation in the digestate by 54%, and increased specific methane yield per wet weight by 25%. This level of effect was not noted for seaweed harvested in September, when the biodegradability is higher.

2024, Renewable & Sustainable Energy Reviews

Resource depletion and mitigation of climate change are the driving forces to find alternatives to fossil fuels. Seaweeds (macroalgae) have been considered as a promising alternative source of biofuels due to higher growth rates, greater production yields and a higher rate of carbon dioxide fixation, than land crops. A comparatively easily depolymerized structure, lack of need of arable land and no fresh water requirement for cultivation, make seaweed a potential feedstock for gaseous biofuel production. Biomethane potential of seaweed is greatly dependent on its chemical composition that is highly variable due to its type, habitat, cultivation method and time of harvest. Saccharina latissima and Laminaria digitata are the highest biomethane yielding Irish brown seaweeds. Seaweed harvested in July (northern hemisphere) was estimated to give gross energy yields in the range 38-384 GJ ha −1 yr −1 ; higher values are dependent on innovative cultivation systems. An integrated model is suggested where seaweed can be co-digested with other feedstock for the sustainable production of gaseous fuel to facilitate EU renewable energy targets in transport.

2024, Bioresource Technology

The manual manometric biochemical methane potential (mBMP) test uses the increase in pressure to calculate the gas produced. This gas production may be affected by the headspace volume in the incubation bottle and by the overhead pressure measurement and release (OHPMR) frequency. The biogas and methane yields of cellulose, barley, silage and slurry were compared with three incubation bottle headspace volumes (50, 90 and 180 ml; constant 70 ml total medium) and four OHPMR frequencies (daily, each third day, weekly and solely at the end of experiment). The methane yields of barley, silage and slurry were compared with those from an automated volumetric method (AMPTS). Headspace volume and OHPMR frequency effects on biogas yield were mediated mainly through headspace pressure, with the latter having a negative effect on the biogas yield measured and relatively little effect on methane yield. Two mBMP treatments produced methane yields equivalent to AMPTS.

2024, Bioresource Technology

Four feedstocks were assessed for use in a demand driven biogas system. Biomethane potential (BMP) assays were conducted for grass silage, food waste, Laminaria digitata and dairy cow slurry. Semi-continuous trials were undertaken for all feedstocks, assessing biogas and biomethane production. Three kinetic models of the semi-continuous trials were compared. A first order model most accurately correlated with gas production in the pulse fed semi-continuous system. This model was developed for production of electricity on demand, and biomethane upgrading. The model examined a theoretical grass silage digester that would produce 435 kW e in a continuous fed system. Adaptation to demand driven biogas required 187 minutes to produce sufficient methane to run a 2MW e combined heat and power (CHP) unit for 60 minutes. The upgrading system was dispatched 71 minutes following CHP shutdown. Of the biogas produced 21% was used in the CHP and 79% was used in the upgrading system.

2024, Applied Energy

The total theoretical biomethane resource of grass silage in a region was estimated. A theoretical biomethane resource of ca. 138 PJ was identified. An optimisation model determined profitable biomethane facility locations. Profitable plants produced 12 PJ of biomethane, 8.6% of the theoretical resource. Approximately 22% of industrial gas demand could be supplied by profitable plants.

2024, Energy

Seaweed may be a source of third generation gaseous biofuel, in the form of biomethane. The scientific literature is sparse on the relative suitability of different varieties of seaweed to produce biomethane. This paper assesses the BMP (biochemical methane potential), ultimate analysis and theoretical yields of ten species of seaweed which may be found in commercial quantities around the coastline of Ireland. Saccharina latissima reported the highest BMP yield (ca. 342 L CH 4 kg VS À1). S. latissima if farmed, may produce 10,250 m 3 CH 4 ha À1 yr À1 (365 GJ ha À1 yr À1) which is in excess of all land based liquid biofuel systems.

2024, Waste Management

Ulva lactuca (commonly known as sea letuce) is a green sea weed which dominates Green Tides or algae blooms. Green Tides are caused by excess nitrogen from agriculture and sewage outfalls resulting in eutrophication in shallow estuaries. Samples of U. lactuca were taken from the Argideen estuary in West Cork on two consecutive years. In year 1 a combination of three different processes/pretreatments were carried out on the Ulva. These include washing, wilting and drying. Biomethane potential (BMP) assays were carried out on the samples. Fresh Ulva has a biomethane yield of 183 L CH 4 /kg VS. For dried, washed and macerated Ulva a BMP of 250 L CH 4 /kg VS was achieved. The resource from the estuary in West Cork was shown to be sufficient to provide fuel to 264 cars on a year round basis. Mono-digestion of Ulva may be problematic; the C:N ratio is low and the sulphur content is high. In year 2 co-digestion trials with dairy slurry were carried out. These indicate a potential increase in biomethane output by 17% as compared to mono-digestion of Ulva and slurry.

2024

In this study, culture of Chlorella vulgaris in food effluent and its specific growth rate, biomass, chlorophyll a, chlorophyll b, total carotenoids and removal of nitrate and phosphate under the red light emitting diodes (R-LED) and fluorescent light (FL) were investigated. For these purposes, C. vulgaris were cultured in two concentrations of 10% (treatment of 10% W), 15% (treatment of 15% W) as mixotrophic model (Mix) of food effluent and BBM as autotrophic model (Auto) under red LED and fluorescence light for 15 days. Therefore, six different treatments were assigned as; BBM + FL (Auto), 10%W + FL (Mix), 15%W + FL (Mix), BBM + R-LED (Auto), 10%W + R-LED (Mix) and 15%+R-LED (Mix). The experiment conditions were 24 hours light photoperiod, water temperature of 26°C and a light intensity of 300 µmol photons m− 2 s− 1 for red LED light and 35 µmol photons m− 2 s− 1 for fluorescent treatments. The highest amount of chlorophyll a (1.60 mgL− 1), cell density (46.6 × 106 cell/mL), speci...