Sustainable Biofuel Research Articles

Integration of plant and microbial oil processing at oilcane biorefineries for more sustainable biofuel production

AbstractOilcane—an oil‐accumulating crop engineered from sugarcane—and microbial oil have the potential to improve renewable oil production and help meet the expected demand for bioderived oleochemicals and fuels. To assess the potential synergies of processing both plant and microbial oils, the economic and environmental implications of integrating microbial oil production at oilcane and sugarcane biorefineries were characterized. Due to decreased crop yields that lead to higher simulated feedstock prices and lower biorefinery capacities, current oilcane prototypes result in higher costs and carbon intensities than microbial oil from sugarcane. To inform oilcane feedstock development, we calculated the required biomass yields (as a function of oil content) for oilcane to achieve financial parity with sugarcane. At 10 dw% oil, oilcane can sustain up to 30% less yield than sugarcane and still be more profitable in all simulated scenarios. Assuming continued improvements in microbial oil production from cane juice, achieving this target results in a minimum biodiesel selling price of 1.34 [0.90, 1.85] USD∙L−1 (presented as median [5th, 95th] percentiles), a carbon intensity of 0.51 [0.47, 0.55] kg CO2e L−1, and a total biodiesel yield of 2140 [1870, 2410] L ha−1 year−1. Compared to biofuel production from soybean, this outcome is equivalent to 3.0–3.9 as much biofuel per hectare of land and a 57%–63% reduction in carbon intensity. While only 20% of simulated scenarios fell within the market price range of biodiesel (0.45–1.11 USD∙L−1), if the oilcane biomass yield would improve to 25.6 DMT∙ha−1∙y−1 (an equivalent yield to sugarcane) 87% of evaluated scenarios would have a minimum biodiesel selling price within or below the market price range.

Advancements in lignocellulolytic multienzyme bioprocesses for sustainable biofuels and biochemicals: strategies, innovations, and future prospects

Advancements in lignocellulolytic multienzyme bioprocesses for sustainable biofuels and biochemicals: strategies, innovations, and future prospects

Recycling waste tires into sustainable biofuel for replacing petroleum fuel in diesel engines using nanoparticles and biohydrogen.

In this paper, the production of pyrolyzed oil in lab scale plant and its possible use in variable speed diesel engine with nanoparticle and secondary fuel oxy-hydrogen gas is investigated. The pyrolyzed oil is produced from waste tires in lab scale plant, and after its distillation, it is blended with neat diesel in the proportion of 20:80 (TDF). The different testing fuels are prepared by mixing nanoparticle CeO2 (NP) at the concentrations 50ppm and 100ppm with blended fuel (named as TDF-NP50 and TDF-NP100). While in the testing phase, the HHO gas is supplied through specially designed venturi at fixed flow rate (fuel designated as TDF-NP50-HHO and TDF-NP100-HHO). The focus of current investigation is to investigate the combined impact of inducting HHO with nanoparticle mixed pyrolyzed blends on engine performance and emissions characteristics. The pyrolyzed blended fuel deteriorate the BTE, BSFC, emissions of HC and NOx while improves the CO emission. The improvement in all the characteristics can be achieved by introducing CeO2 nanoparticle at 50ppm and 100ppm which improves BTE by 15-24%, BSFC by 2.2-4.2%, HC by 8-18%, CO by 7-12%, and NOx by 7-16%. The further improvement can be achieved by inducting HHO gas, which are BTE 11%, BSFC 5-8%, HC 15%, and CO 13-16%. However, the NOx emission is increased by 14-17%. Hence, the waste tire-derived pyrolyzed oil along with green hydrogen and nanoparticles CeO2 can be used as a sustainable transportation fuel in existing CI engine.

Applications of Machine Learning Technologies for Feedstock Yield Estimation of Ethanol Production

Biofuel has received worldwide attention as one of the most promising renewable energy sources. Particularly, in many countries such as the U.S. and Brazil, first-generation ethanol from corn and sugar cane has been used as automobile fuel after blending with gasoline. Nevertheless, in order to continuously increase the use of biofuels, efforts are needed to reduce the cost of biofuel production and increase its profitability. This can be achieved by increasing the efficiency of a sequential biofuel production process consisting of multiple operations such as feedstock supply, pretreatment, fermentation, distillation, and biofuel transportation. This study aims at investigating methodologies for predicting feedstock yields, which is the earliest step for stable and sustainable biofuel production. Particularly, this study reviews feedstock yield estimation approaches using machine learning technologies that focus on gradually improving estimation accuracy by using big data and computer algorithms from traditional statistical approaches. Given that it is becoming increasingly difficult to stably produce biofuel feedstocks as climate change worsens, research on developing predictive modeling for raw material supply using the latest ML techniques is very important. As a result, this study will help researchers and engineers predict feedstock yields using various machine learning techniques, and contribute to efficient and stable biofuel production and supply chain design based on accurate predictions of feedstocks.

Conversion of kraft lignin to hydrocarbons using an integrated molten salt pyrolysis/catalytic hydrotreatment approach

Thermochemical conversion of underutilized lignocellulosic streams such as kraft lignin from the pulp and paper industry has the potential to produce sustainable chemicals and biofuels. We here report a process to continuously convert softwood-based lignoboost lignin to hydrocarbons using a three-step approach: i) liquefaction/dispersion of the lignin in a suitable molten salt, ii) pyrolysis of the liquefied/dispersed lignin in a molten salt mixture (ZnCl2, KCl, and NaCl), to obtain a crude lignin oil and iii) upgrading of the lignin oil using a catalytic hydrotreatment to yield hydrocarbons. Step 1 and 2 were integrated using a twin screw extruder with different heating sections at a scale of 20 g/h lignin input. Besides char, a lignin oil, mainly composed of monomeric phenolics, and propylene were the major products. The highest yield of the latter two products was around 32 wt% (23 wt% crude lignin oil and 9 wt% propylene). The lignin oil was subsequently converted to hydrocarbons using a two-step catalytic hydrotreatment approach (stabilization step using CoMo/Al2O3 catalyst and a further deep hydrotreatment over a NiMo/Al2O3 catalyst). The final liquid product contained less than 0.5 wt% of oxygen and was shown to be rich in (cyclo)alkanes and aromatic hydrocarbons. The carbon yield for the overall conversion of lignin to hydrocarbons was 23 %.

Catalytic hydrogenation of waste-derived lipids: A route to producing sustainable drop-in biofuels by using Re/TiO2 catalysts

The urgent threat of climate change compels modern society to transition to alternative energy sources swiftly. The production of sustainable liquid biofuels capable of substituting fossil-derived fuels is a topic of great interest. This study explores the effectiveness of Re/TiO2 catalysts in producing drop-in biofuels from waste-derived feedstock. Specifically, four Re-based catalysts supported on different TiO2 materials, namely TiO2 P25, TiO2 FSP, TiO2 M, TiO2 COTIOX were synthesized using the wet impregnation method, characterized and tested in the hydrodeoxygenation reaction of fatty acids, to uncover fundamental insight into this process. These catalysts exhibited varying levels of effectiveness. Apart from Re/TiO2 COTIOX, which showed the lowest conversion of fatty acids (30 %), the other three catalysts allowed over 98 % conversion of fatty acids into hydrocarbons after 6 h reaction, at 35 bar of H2, under solvent-free conditions and without pre-reduction of the catalyst. Notably, Re/TiO2 P25 was the most effective, attaining this remarkable result at 300 °C. The remaining catalysts, Re/TiO2 FSP and Re/TiO2 M, required higher temperatures (350 °C) to achieve complete hydrogenation of fatty acids into hydrocarbons. These effective catalysts also demonstrated great recoverability, reusability, and robustness, successfully converting waste-derived lipids, such as grease recovered from urban sewage sludge and waste cooking oil, into hydrocarbons. These findings underscore Re/TiO2 as a promising robust catalyst for waste-derived lipids hydrogenation, enabling the efficient production of drop-in biofuels and paving the way for innovative solutions in the renewable energy landscape.

Hydrothermal liquefaction: exploring feedstock for sustainable biofuel production

A number of technological strategies utilizing various types of biomass for the production of hydrocarbons have been put forth but their energy intensive methods are a concern for improved efficiency of biofuel production. Hydrothermal liquefaction (HTL) has emerged as a promising and feasible technology towards utilization of lignocellulosic biomass. The suitability of different biomass feedstock for HTL is intricately tied to their macromolecular composition and process parameters. The comprehensive analysis of feedstock for hydrothermal liquefaction (HTL) signal towards the immense potential of various biomass feedstock, such as corn stover, Miscanthus, pine biomass, Spirulina, sugarcane bagasse, rice bran etc. in contributing significantly to renewable energy production. The study emphasizes that the composition of biomass is critical in influencing bio-oil yield during the HTL process. Biomass components like cellulose, hemicellulose, and lignin, each play distinct roles in determining the efficiency of conversion. Specifically, feedstock with higher cellulose and hemicellulose content, such as Miscanthus and sugarcane bagasse, demonstrate superior bio-oil yields. The analysis of proximate factors affecting HTL efficiency reveals that moisture content, ash content and high heating value (HHV) are pivotal in optimizing the process. In addition to composition and physical characteristics, the article underscores the significance of growth conditions and nutrient utilization in cultivating biomass feedstock. Integrating HTL with biomass cultivation can create a sustainable, closed-loop system where nutrients from the HTL process are recycled back into cultivation. Biomass offers a renewable energy alternative, however it also poses challenges related to land use and potential competition with food production. Sustainable practices, such as utilizing agricultural and forestry residues and optimizing collection as well as storage processes, can alleviate some of these concerns. By optimizing feedstock selection, process parameters, and integrating sustainable practices, HTL can play a decisive role in advancing biofuel production and contributing to a more sustainable energy future. The interplay between biomass composition, processing efficiency, environmental impacts, and economic feasibility is essential for realizing the full potential of HTL technology in the bio-economy. The current analysis sheds light on the relationship of bio-oil yield with macromolecular components including cellulose, hemicellulose, and lignin as well as process parameters like ash content, moisture content, higher heating value, fixed carbon and volatiles. Focusing on process optimization, this study embodies a closer analysis of literature aimed at defining optimum strategies for enhancement of HTL.

Developing microalgae harvesting: Enhanced efficiency with magnetite-urea nanocomposites for sustainable astaxanthin biorefinery

Harvesting costs, accounting for 15–30 % of total expenses, are a major bottleneck in microalgae biorefinery due to low cell density and energy-intensive processes. This study investigates Fe3O4-Urea (Fe@urea) nanocomposites (NCs) to replace conventional methods and improve the harvesting efficiency (HE) of Chlorella zofingiensis, known for its high lipid and astaxanthin content. Urea-coated magnetite nanoparticles (NPs) with additional functional groups significantly improved harvesting performance across all pH levels compared to conventional Fe3O4 NPs. HE was evaluated using both optical density and cell counting methods, with the latter proving superior results by eliminating interference from unreacted salts and debris. Optimization of nanocomposite concentrations and culture pH with Fe@urea achieves 95 % HE at 800 mg L−1 and pH 3–4. The Langmuir and Freundlich models confirmed the nanocomposite's multifaceted capabilities. Characterization techniques included SEM, FTIR, EDX, zeta potential analysis, and TEM. This innovative approach can revolutionize large-scale microalgae biorefineries, enhancing sustainable biofuel and bioproduct production and supporting the Sustainable Development Goal of Affordable and Clean Energy (SDGs 7).

Heavea brasilienis (Rubber seed oil) as cost effective non edible feedstock for sustainable high quality biofuel production.

Biodiesel is renewable fuel acquired from biomass which has short chain alkyl esters derived from vegetable oil or animal fats. It has greater advantages over traditional diesel oil. In first level esterification, H2SO4 is used because the acid catalyst to decrease the FFA from 4. 5% to 0. 85 %. In 2nd stage, transesterification chemical process was carried with methanol and NaOH, the elevated temperature 600c and response time is 45 min to 75min. Only a few experiments have been carried out for evaluating the results of equation using a Scientific tool.

Production and optimization of biofuels from locally isolated algal biomass: Strategies for circular economy integration

In the present study, we investigated the potential of locally isolated algal strains as alternative energy sources for sustainable biofuel production. The focus of this study was to identify algal strains that are capable of accumulating oils rich in essential fatty acids. Algal samples were collected from different areas and 14 isolates were obtained. Among the various pretreatment methods tested, hydrothermal pretreatment using sulfuric acid at 95 °C yielded the best results, with sample IIB-14 containing more than 2% reducing sugars. These sugars were then used for fermentation with the S. cerevisiae strain, resulting in an ethanol concentration of 3.52% ± 0.2%. This holistic approach contributes to the development of low-cost and environmentally friendly alternatives to traditional energy sources. While algal biofuels offer a promising substitute for fossil fuels, further advancements are needed before they can be widely adopted in the fuel market. Among these, isolates IIB-8 and IIB-9 showed the highest oil yields of 22.84% and 24.69% (w/w), respectively. The specific environmental settings for optimal growth of these strains were determined, and the physicochemical parameters of the oils, including iodine value, viscosity, density, acid value, saponification value, unsaponifiable mass, and peroxide value, were analyzed. The transesterification of oils into fatty acid methyl esters (FAMEs) revealed the presence of significant amounts of fatty acids, including EPA, DHA, and linoleic acid. Moreover, the study also explored the potential of algal biomass for bioethanol production, addressing the sustainability concerns of renewable energy supplies. Hydrothermal pretreatment using sulfuric acid at 95 °C yielded the highest concentration of reducing sugars (>2%) in IIB-14. Sugar extracted from algal biomass was used for fermentation. The Saccharomyces cerevisiae strain used for the fermentation process yielded an ethanol concentration of 3.52% ± 0.2%. This holistic approach contributes to the development of low-cost and environment-friendly alternatives to renewable energy sources. Algal biofuels may offer a practical substitute for fossil fuels, but there is still a long way to go before they can enter the fuel market and are widely used.

Sustainable Production of Biofuels from Biomass Feedstocks Using Modified Montmorillonite Catalysts.

The rampant exploitation of fossil fuels has led to the significant energy scarcity and environmental disruption, affecting the sound momentum of development and progress of human civilization. To build a closed-loop anthropogenic carbon cycle, development of biofuels employing sustainable biomass feedstocks stands at the forefront of advancing carbon neutrality, yet its widespread adoption is mainly hampered by the high production costs. Montmorillonite, however, has garnered considerable attention serving as an efficient heterogeneous catalyst of ideal economic feasibility for biofuel production, primarily due to its affordability, accessibility, stability, and excellent plasticity. Up to now, nevertheless, it has merely received finite concerns and interests in production of various biofuels using montmorillonite-based catalysts. There is no timely and comprehensive review that addresses this latest relevant progress. This review fills the gap by providing a systematically review and summary in controllable synthesis, performance enhancement, and applications related to different kinds of biofuels including biodiesel, biohydrogenated diesel, levulinate, γ-valerolactone, 5-ethoxymethylfurfural, gaseous biofuels (CO, H2), and cycloalkane, by using montmorillonite catalysts and its modified forms. Particularly, this review critically depicts the design strategies for montmorillonite, illustrates the relevant reaction mechanisms, and assesses their economic viability, realizing sustainable biofuels production via efficient biomass valorization.

Production of Bio-Oil from Sugarcane Bagasse through Hydrothermal Liquefaction Processes with Modified Zeolite Socony Mobil-5 Catalyst

In response to the increasing global demand for sustainable energy alternatives, this research explores the efficient conversion of sugarcane bagasse to bio-oil through hydrothermal liquefaction (HTL) processes with modified Zeolite Socony Mobil-5 catalysts (ZSM-5). The study systematically investigates the impact of feedstock quantity, reaction temperature, duration, and catalyst loading on bio-oil yield and quality. Optimisation experiments revealed that a feedstock amount of 10 grammes, an HTL temperature of 340 °C for 60 min and a ZSM-5 catalyst loading of 3 grammes resulted in the highest bio-oil yield. Furthermore, the introduction of Ni and Fe metals to ZSM-5 exhibited enhanced catalytic activity without compromising the structure of the zeolites. Comprehensive characterisation of modified catalysts using SEM-EDS, XRD, TGA, TEM, and FTIR provided insight into their structural and chemical properties. The successful incorporation of Ni and Fe into ZSM-5 was confirmed, highlighting promising applications in hydrothermal liquefaction. Gas chromatography–mass spectrometry (GC-MS) analysis of bio-oils demonstrated the effectiveness of the 2% Fe/ZSM-5 catalyst, highlighting a significant increase in hydrocarbon content. FTIR analysis of the produced bio-oils indicated a reduction in functional groups and intensified aromatic peaks, suggesting a shift in chemical composition favouring aromatic hydrocarbons. This study provides valuable information on HTL optimisation, catalyst modification, and bio-oil characterisation, advancing the understanding of sustainable biofuel production. The findings underscore the catalytic prowess of modified ZSM-5, particularly with iron incorporation, in promoting the formation of valuable hydrocarbons during hydrothermal liquefaction.

Sustainable biofuels from corncobs: optimization of microwave pretreatment for enhanced fermentable sugar yield

Microwave-Assisted Alkali (MAA) pretreatment of corncob biomass was optimized for maximum fermentable sugar yield using dilute sulfuric acid hydrolysis. A Central Composite Design (CCD) investigated the effects of microwave power (450–9000 W), NaOH concentration (1.5 to 4.5% wt./v), and irradiation time (10–20 min) on lignin removal. The optimal MAA pretreatment conditions were found to be 691.73 W, 3.4% NaOH, and 15.5 min, resulting in the selective removal of 73.36% lignin with high retention of cellulose (71.69%) and hemicellulose (22.14%). Characterization techniques (FTIR, SEM, XRD, TGA) confirmed substantial changes in surface morphology, functional groups, crystallinity, and thermal stability of the pretreated corncobs. Dilute sulfuric acid hydrolysis (0.5–2.5%, 110130 °C, 3060 min) of the optimized sample yielded a maximum reducing sugar output of 537.42 mg/g, achieved at 0.534% H2SO4, 122.3 °C, for 58 min. Optimizing Microwave-Assisted Alkali pretreatment process for corncobs could boost biofuel production efficiency, sustainably utilize agricultural waste, and advance a more sustainable energy landscape.

Assessing the Sustainability of Diverse Biofuels through Life Cycle and Techno-Economic Analysis

The global shift towards sustainable energy sources has spurred extensive exploration of biofuels as promising substitutes for traditional fossil fuels. Yet, pinpointing the optimal biofuel necessitates a nuanced evaluation across environmental, economic, and technological fronts. This study undertakes a comparative analysis of three prominent biofuels—biodiesel, bioethanol, and biogas—employing a multi-faceted assessment framework integrating both Life Cycle Assessment (LCA) and Techno-Economic Assessment (TEA). Through a comprehensive examination encompassing environmental impacts, economic viability, and operational efficacy, this research offers insights into the strengths and limitations inherent in each biofuel variant. By shedding light on the sustainability prospects of these biofuels across diverse applications, the findings aim to furnish stakeholders with informed guidance for selecting the most fitting and sustainable biofuel options.

Valorization of fish waste for sustainable biofuel production: A case study in Ghana

Fish processing plants generate significant waste annually, which harms the environment. To tackle this, the waste can be converted into biofuel, pharmaceuticals, fertilizer, and animal feed. Biofuels, specifically biogas and biodiesel, are emphasized for their eco-friendly properties that help combat global warming. The study focuses on producing biodiesel through transesterification and biogas via anaerobic digestion of fish waste. Analyses of the rate constant (K), activation energy (Ea), entropy (ΔS), enthalpy (ΔH), and Gibbs free energy (ΔG) at varied temperatures show highest Ea, K, ΔH, and ΔS values of 60.74 kJ/mol, 31.43 s−1, 66.01 kJ/mol, and 30.99 kJ/mol K, respectively. The biodiesel was also characterized by Fourier transform infrared (FTIR) spectroscopy and kinematic viscosity. Additionally, the properties; relative density, viscosity, oxidation stability, pour point, cloud point, flash point, and cetane number were found to be 0.669, 5.090 mm2s−1, >7, −7 °C, 0.999 °C, 151 °C, and 51, respectively. Biogas production using varying ratios of fish waste and cow dung (1:1,1:2, 1:3, and 1:4) indicates that a 1:4 ratio yields optimal results with 69% methane (CH4) and 21.5% carbon dioxide (CO2), suitable for scalable biogas production. The process is efficient at a neutral pH (7.1–7.3) and 27 °C, offering a viable solution to reduce fish waste pollution while generating renewable energy. Finally, a proposed model of a biodigester for optimum biogas production is discussed.

Enhancing bioethanol yield from food waste: Integrating decontamination strategies and enzyme dosage optimization for sustainable biofuel production

Amidst the global surge in energy demand, the public’s focus has shifted from fossil fuels to more sustainable and eco-friendly fuels like bioethanol. Thus, the prospect of producing bioethanol from food waste (FW) is gaining traction, offering a sustainable solution to both waste management and energy needs. However, increasing bioethanol yields during food waste fermentation requires an approach that addresses the variability of these heterogeneous feedstocks in terms of chemical composition, microbial contamination, enzyme dosage requirements, and high moisture content. Hence, this study evaluated thermal and chemical decontamination strategies for pre- and post-consumer food waste and minimised the exogenous enzyme dosage by applying an engineered, amylase-producing strain (Saccharomyces cerevisiae ERT12). Results show that thermal sterilisation at an elevated liquefaction temperature significantly improved ethanol yields (from pre-and post-consumer food waste) more than chemical decontamination methods. Also, key findings show that applying the amylase-secreting yeast reduced enzyme dosages by up to 33 %. During fed-batch fermentation with strain ER T12, the highest possible solids loading increased the final ethanol concentrations by 96 % (for pre-consumer FW) and 85 % (for post-consumer FW) compared to batch fermentation. Also, the pre-consumer to post-consumer FW fed-batch fermentation maintained acceptable volumetric production rates of 2.35 to 1.57 g/l.h and yielded 87.6 to 61.2 % of the theoretical maximum. Although the maximum solids loadings, ethanol titres and yields achievable in food waste fermentations were still limited by the inherent moisture contents of the feed, they demonstrated performances that may be appropriate for industrial implementation, considering the negative feedstock costs.

Utilizing cocoa bean husk residues from supercritical extraction for biofuel production through hydrothermal liquefaction

This study aimed to develop an efficient method for converting residual biomass into biofuel through a process that combines supercritical fluid extraction and hydrothermal liquefaction. The study analyzed the compositional changes in the biomass residues using various co-solvents and assessed their potential for biofuel production. After hydrothermal liquefaction, the liquid biofuel produced showed a decrease in the H to C ratio from 1.7 to 1.6 and a reduction in the O to C ratio from 0.5 to 0.2, compared to the unprocessed feedstock, indicating a favorable alteration in elemental composition for biofuel production. Notably, residues extracted with supercritical CO2 and ethanol had the lowest yield, while those extracted with CO2 and water achieved the highest energy recovery at 101.5%. These findings suggest that integrating supercritical fluid extraction with hydrothermal liquefaction is an environmentally sustainable and efficient approach, significantly advancing the development of sustainable biofuels.

Eco-friendly production of biodiesel from Carthamus tinctorius L. seeds using bismuth oxide nanocatalysts derived from Cannabis sativa L. Leaf extract

Global challenges in environmental protection, social welfare, and economic growth necessitate increased energy production and related services. Biofuel production from waste biomass presents a promising solution, given its widespread availability. This study focuses on converting highly potent Carthamus tinctorius L. seed oil (51 % w/w) into sustainable biofuel using a novel, highly reactive, recyclable, and eco-friendly bismuth oxide (Bi2O3) nano-catalyst derived from Cannabis sativa L. leaf extract. The physio-chemical properties of the synthesized biodiesel were analyzed using Gas Chromatography/Mass Spectroscopy (GC-MS), Nuclear Magnetic Resonance (NMR), and Fourier-Transform Infrared Spectroscopy (FTIR). Additionally, the green Bi2O3 nanoparticles were characterized through Scanning Electron Microscopy (SEM), Energy Diffraction X-Ray (EDX), and X-Ray Diffraction (XRD). Optimal conditions for biodiesel production were determined using Response Surface Methodology (RSM) in combination with Central Composite Design (CCD), focusing on molar ratio, catalyst loading, and reaction duration. The highest output (94 %) of C. tinctorius-derived biodiesel (CTBD) was achieved under the following conditions: a temperature (75 °C) for time duration (100 min), a methanol to oil ratio (6:1), and a catalyst loading (0.69 wt%). The resulting biodiesel met international standards, with a sulphur content of 0.00097 wt%, and an acid value of (0.34 mg KOH/g). This study demonstrates that converting C. tinctorius waste seed oil into clean bioenergy is an effective waste management strategy that minimizes environmental impact.

Advancements in Synthetic Biology for Enhancing Cyanobacterial Capabilities in Sustainable Plastic Production: A Green Horizon Perspective

This comprehensive review investigates the potential of cyanobacteria, particularly nitrogen-fixing strains, in addressing global challenges pertaining to plastic pollution and carbon emissions. By analyzing the distinctive characteristics of cyanobacteria, including their minimal growth requirements, high photosynthetic efficiency, and rapid growth rates, this study elucidates their crucial role in transforming carbon sequestration, biofuel generation, and biodegradable plastic production. The investigation emphasizes cyanobacteria’s efficiency in photosynthesis, positioning them as optimal candidates for cost-effective bioplastic production with minimized land usage. Furthermore, the study explores their unconventional yet promising utilization in biodiesel production, mitigating environmental concerns such as sulfur emissions and the presence of aromatic hydrocarbons. The resulting biodiesel exhibits significant combustion potential, establishing cyanobacteria as a viable option for sustainable biofuel production. Through a comprehensive assessment of both achievements and challenges encountered during the commercialization process, this review offers valuable insights into the diverse contributions of cyanobacteria. Its objective is to provide guidance to researchers, policymakers, and industries interested in harnessing bio-inspired approaches for structural and sustainable applications, thereby advancing global efforts towards environmentally conscious plastic and biofuel production.

Role of cultivation parameters in carbohydrate accretion for production of bioethanol and C-phycocyanin from a marine cyanobacterium Leptolyngbya valderiana BDU 41001: A sustainable approach

The investigation aimed to augment carbohydrate accumulation in the marine cyanobacterium Leptolyngbya valderiana BDU 41001 to facilitate bioethanol production. Under the standardised physiochemical condition (SPC), i.e. 90 µmol photon m−2 s−1 light intensity, initial culture pH 8.5, 35 °C temperature and mixing at 150 rpm increased the carbohydrate productivity ∼70 % than the control, while a 47 % rise in content was obtained under the nitrate (N)-starved condition. Therefore, a two-stage cultivation strategy was implemented, combining SPC at the 1st stage and N starvation at the 2nd stage, resulting in 80 % augmentation of carbohydrate yield, which enhanced the bioethanol yield by ∼86 % as compared to the control employing immobilised yeast fermentation. Moreover, biomass utilisation was maximised by extracting C-phycocyanin, where a ∼77 % rise in productivity was recorded under the SPC. This study highlights the potential of L. valderiana for pilot-scale biorefinery applications, advancing the understanding of sustainable biofuel production.