Bioeconomy Research Articles

LCA standards for environmental product assessments in the bioeconomy with a focus on biogenic carbon: A systematic review

Abstract Purpose Climate change mitigation is one of the priorities of the European Bioeconomy Strategy (BES). In this regard, renewable raw materials are a crucial resource, as they help to substitute fossil resources and reduce greenhouse gas (GHG) emissions by storing biogenic carbon (C). To control the environmental impact of the European BES, the life cycle assessment (LCA) is the preferred method. Standards provide guidance for LCA. This review aims to present the state of the art of LCA-related standards, focusing on the assessment of biogenic C and its global warming potential (GWP) to evaluate them for decision-making with regard to the transition to a bioeconomy (BE) and climate change mitigation. Methods A systematic review is conducted using the database Nautos to reveal the relevant standards guiding LCA in the BE. In an iterative process, criteria for a comparative analysis are defined. The eligible standards are then qualitatively analysed and compared based on criteria previously derived in the iterative process. Results and discussion In the context of LCA and bio-based products, 13 documents are identified. Differences are revealed in the accounting of biogenic C flows, the calculation of the duration of biogenic C storage and the biogenic C content as well as the consideration of substitution effects. Furthermore, the standards do not provide any information on the assessment of biogenic C in the circular economy so far. Conclusion The importance of biogenic C aspects in LCA has been reflected in the standards over the last 20 years. However, further research is needed to harmonise the different aspects and integrate new relevant ones related to biogenic C and BE to support decision-making for the transition to a BE. This becomes more important as new legislation refers to LCA standards as the preferred assessment method.

Remote Sensing, Artificial Intelligence and Smart Agriculture Technology Trends of the Future

The efficient and sustainable operation of the agricultural sector has become increasingly important in light of the transformations brought about by the third and fourth industrial revolutions. Population growth, increasing food demand, rising input costs, and environmental pressures necessitate innovative approaches not only to ensure food security but also to mitigate the effects of climate change. The European Union (EU) emphasizes the role of digital technologies in supporting agricultural productivity and resilience by promoting a bio-based economy. Strategies such as Farm to Fork (F2F) initiative aim to reduce pesticide and nutrient inputs, thus preserving biodiversity and supporting ecosystem health. Artificial intelligence (AI) and predictive analytics, along with connected sensors, offer opportunities to optimize water and nutrient usage and increase crop yields. By utilizing AI, combining remote sensing technologies, and monitoring changes in land use, it is possible to reduce environmental risks associated with agricultural practices. Although there are challenges such as high investment costs and data control for the integration of digital technologies, ongoing research and development efforts promise to overcome these obstacles. In conclusion, the integration of digital technologies into agriculture presents unique opportunities to address urgent issues and achieve sustainability goals. This review discusses the applicability of fundamental technologies such as the Internet of Things (IoT), Artificial Intelligence (AI), Precision Agriculture (PA), and Machine Learning (ML) in making agriculture more efficient and sustainable, by enabling the perception, monitoring, collection, analysis, and extraction of meaningful insights from agricultural data.

Unlocking the Potential of Hydrosols: Transforming Essential Oil Byproducts into Valuable Resources

The global demand for sustainable and non-toxic alternatives across various industries is driving the exploration of naturally derived solutions. Hydrosols, also known as hydrolates, represent a promising yet underutilised byproduct of the extraction process of essential oils (EOs). These aqueous solutions contain a complex mixture of EO traces and water-soluble compounds and exhibit significant biological activity. To fully use these new solutions, it is necessary to understand how factors, such as distillation time and plant-to-water ratio, affect their chemical composition and biological activity. Such insights are crucial for the standardisation and quality control of hydrosols. Hydrosols have demonstrated noteworthy properties as natural antimicrobials, capable of preventing biofilm formation, and as antioxidants, mitigating oxidative stress. These characteristics position hydrosols as versatile ingredients for various applications, including biopesticides, preservatives, food additives, anti-browning agents, pharmaceutical antibiotics, cosmetic bioactives, and even anti-tumour agents in medical treatments. Understanding the underlying mechanisms of these activities is also essential for advancing their use. In this context, this review compiles and analyses the current literature on hydrosols’ chemical and biological properties, highlighting their potential applications and envisioning future research directions. These developments are consistent with a circular bio-based economy, where an industrial byproduct derived from biological sources is repurposed for new applications.

Green carbon and the chemical industry of the future

The pressing need to mitigate climate change and drastically reduce environmental pollution and loss of biodiversity has precipitated a so-called energy transition aimed at the decarbonization of energy and defossilization of the chemical industry. The goal is a carbon-neutral (net-zero) society driven by sustainable energy and a circular bio-based economy relying on renewable biomass as the raw material. It will involve the use of green carbon, defined as carbon derived from terrestrial or aquatic biomass or organic waste, including carbon dioxide and methane emissions. It will also necessitate the accompanying use of green hydrogen that is generated by electrolysis of water using a sustainable source of energy, e.g. solar, wind or nuclear. Ninety per cent of the industrial chemicals produced in oil refineries are industrial monomers that constitute the precursors of a large variety of polymers, many of which are plastics. Primary examples of the latter are polyolefins such as polyethylene, polypropylene, polyvinyl chloride and polystyrene. Polyolefins are extremely difficult to recycle back to the olefin monomers and discarded polyolefin plastics generally end up as the plastic waste that is responsible for the degradation of our natural habitat. By contrast, waste biomass, such as the lignocellulose contained in forestry residues and agricultural waste, constitutes a renewable feedstock for the sustainable production of industrial monomers and the corresponding polymers. The latter could be the same polyolefins that are currently produced in oil refineries but a more attractive long-term alternative is to produce polyesters and polyamides that can be recycled back to the original monomers: a paradigm shift to a truly bio-based circular economy on the road to a net-zero chemical industry. This article is part of the discussion meeting issue ‘Green carbon for the chemical industry of the future’.

A case study of the regional bioeconomy in Central Germany: construction with renewable resources

In response to global challenges like climate change and resource depletion, national and international policies are increasingly emphasising sustainability. The bioeconomy represents a promising field to reconcile environmental integrity with economic development. The objective of this study is to examine the role of renewable resources in the construction industry within the framework of the bioeconomy, with a particular focus on Sustainable Development Goal 11: ‘Sustainable cities and communities’. The case study analyses the practical challenges and opportunities for innovation in Central Germany through a comprehensive regional analysis of construction practices using renewable resources. The methodology involved monitoring biomass flows by assessing harvest yields, area shares and biomass potentials. It also analysed the importance of the bio-based economy by examining employment data and identifying potential growth sectors. Stakeholder engagement was facilitated through knowledge transfer workshops to encourage collaboration and innovation. The results of the study highlight key trends within the industry, including the increasing prevalence of timber buildings, wood as a renewable carbon source in the chemical industry and the growing demand for wood-based packaging solutions. Policy initiatives are playing a supportive role in driving these developments, taking advantage of the region’s extensive wood resources (14.7 million m3 harvested in 2021) and the significant employment contribution of the forestry, wood and construction industries (2% of total employment, representing no less than 81,506 employees). These figures demonstrate the potential for sustainable construction practices to drive local economic growth and contribute to wider environmental objectives.

Conformational Selection in Enzyme-Catalyzed Depolymerization of Bio-based Polyesters.

Enzymatic degradation of polymers holds promise for advancing towards a bio-based economy. However, bulky polymers presents challenges in accessibility for biocatalysts, hindering depolymerization reactions. Beyond the impact of crystallinity, polymer chains can reside in different conformations affecting binding efficiency to the enzyme. We previously showed that the gauche and trans chain conformers associated with crystalline and amorphous regions of the synthetic polyethylene terephthalate (PET) display different affinity to PETase, thus affecting the depolymerization rate. However, structural-function relationships for biopolymers remain poorly understood in biocatalysis. In this study, we explored biodegradation of by-us previously synthesized bio-polyesters made from a rigid bicyclic chiral terpene-based diol and copolymerized with various renewable diesters. Herein, four of those polyesters spanning from semi-aromatic to aliphatic were subjected to enzymatic degradations in concert with induced-fit docking (IFD) analyses. Our findings demonstrate the importance of conformational selection in enzymatic depolymerization of biopolymers. A straight or twisted conformation of the polymer chain is crucial in biocatalytic degradation by showing different affinities to enzyme ground-state conformers. This work highlights the importance of considering the conformational match between the polymer and the enzyme to optimize the biocatalytic degradation efficiency of biopolymers, providing valuable insights for the development of sustainable bioprocesses.

A novel approach to enhance high optically active L-lactate production from food waste by landfill leachate

The recycling of food waste (FW) through anaerobic fermentation into lactic acid (LA), with two isomers L-LA and D-LA, aligns with the principles of a bio-based circular economy. However, FW fermentation is often limited by competing pathways, acidification inhibition, and trace metals deficiency. This study investigates the introduction of landfill leachate, containing buffering agents (ammonia) and trace metals, into FW fermentation. Various dosages of landfill leachate, ranging from 90 (LN-90) to 450 mg/L (LN-450) based on inclusive ammonia calculation, were employed. Results showed that LA production peaked at 43.65 ± 0.57 g COD/L in LN-180 on day 6, with a high optical activity of L-LA at 92.40 ± 1.15 %. Fermentation pathway analysis revealed that landfill leachate amendment enhances hydrolysis (as evidenced by increased activity of amylase, α-glucosidase, and protease) and glycolysis (resulting in enhanced utilization of carbohydrates and glucose). The inclusive ammonia in leachate plays a crucial role as a buffer, maintaining optimal pH conditions (5–7), thereby reducing volatile fatty acid production and thus intensifying LA orientations. The increased activity of L-lactate dehydrogenase (L-LA generation) and decreased NAD-independent lactate dehydrogenase (LA consumption) in properly dosed leachate further explained the high accumulation of L-LA. Dominance of lactic acid bacteria, including Streptococcus, Enterococcus, Klebsiella, Bifidobacterium, Bavariicoccus, and Lacticaseibacillus, accounted for 91.08% (LN-90), while inhibitory effects were observed in LN-450 (4.45%). Functional gene analysis further supported the enhanced glycolysis, L-lactate dehydrogenase, and nitrogen assimilation. Finally, a network analysis indicates a beneficial effect on the genus Enterococcus and Klebsiella by landfill leachate addition. This study demonstrates the efficiency of utilizing landfill leachate to enhance LA recycling from FW fermentation, aligning with the concept of circular economy by transforming waste into valuable resources.

In search of poly-3-hydroxybutyrate (PHB): A comprehensive review unveiling applications and progress in fostering a sustainable bio-circular economy

The escalating demand for economical and durable materials has propelled plastics into an indispensable facet of daily human life, dominating commercial and industrial sectors. The global plastic production of 1.1 billion tons by 2050 exacerbates concerns. The COVID-19 pandemic has further intensified the issue, reaching an alarming 0.3–0.4 billion tons annually. Urgent action is imperative to curtail the drastic environmental impact. Various strategies, particularly microbial involvement in plastic production and degradation, must be implemented to address this. Poly-3-Hydroxybutyrate (PHB) microbial polyesters present a promising alternative to conventional plastics because of their biodegradable nature, thus offering a sustainable solution to plastic pollution. PHBs are employed in divergent industries, including agriculture, medicine, nanotechnology, food, and tissue engineering. This comprehensive review addresses the gap in the literature by encompassing a wide range of topics related to PHBs, their associated enzymes, metabolic pathways, and applications. It also provides an in-depth analysis, highlighting the significance of diverse microbial communities in both the synthesis and degradation of biopolymers. Strategies for augmenting PHA production and leveraging waste products for circular economy initiatives are also discussed, emphasizing the need for innovative solutions to address the global plastic crisis.Top of Form This review highlights two critical strategies for tackling plastic pollution: introducing alternative materials like bioplastics and leveraging biological recycling with microbial assistance. Adopting bio-based circular economy strategies, implementing comprehensive 6 R waste management practices, strengthening plastic pollution regulations, and raising social awareness can significantly improve eco-friendly plastic waste management, diminish pollution, and enhance socio-economic conditions, thus benefiting economies worldwide.

Supplying the ethanol demand for 2030 in Brazil as a land-based climate change mitigation alternative: Implications on greenhouse gases emissions

Transitioning from a fossil-based to a bio-based economy is crucial to climate action and achieving neutrality in greenhouse gas (GHG) emissions. Biofuel production is an essential land-based GHG mitigation alternative. However, it raises concerns about biodiversity conservation, competition with food production, and net GHG emissions associated with direct land-use change (dLUC). This study aims to assess how the location and conversion routes influence GHG emissions for sugarcane expansion in Brazil to supply ethanol demand projections for 2030. A consistent and significant reduction in GHG emissions is achievable by implementing a strategy that prioritizes the spatial distribution for ethanol biorefinery expansions based on georeferenced life cycle emissions, including dLUC emissions associated with sugarcane production. Because of conservative zoning for sugarcane expansion, dLUC emissions are not an overriding factor, representing less than 9.1 % of the total GHG mitigation potential. Despite that, accounting for georeferenced dLUC emissions when prioritizing expansion facilities leads to spatial differences. Regarding conversion routes and land requirements, using cellulosic biorefineries could meet future projected demand based on sugarcane production from 3.1 million hectares, mostly in currently degraded pastureland. Conventional refineries would require 5.5 million hectares to meet the same demand of 71 billion liters. Despite the 77 % higher land demand to produce the same volume of ethanol, conventional refineries with straw recovery could be considered if electricity generation is a priority. This study illustrates how Brazil can achieve GHG mitigation targets while attending to future energy demand and protecting areas with high biodiversity.

Engineering a High Stable and Active RuO2 on Ti Sheet for Kolbe Electrolysis of Acetic Acid: An Investigation to Valorize the Pyroligneous Acid

The efficient utilization of renewable sources based on the simultaneous production of energy fuels and value-added chemicals is an essential to enable a biobased circular economy that benefits carbon neutrality. As an abundant by-product during the pyrolysis of biomass, pyroligneous acid is rich in acetic acid (CH3COOH) that is difficult to handle due to its highly acidic content. However, it is essential made up of renewable carbon that can be converted into valuable chemicals and fuels (e.g. methane, ethane, propane). Herein, we fabricate a highly stable and effective ruthenium oxide electrocatalyst (RuO2/TiOx) via using available titanium sheet as the substrate, to highly selectively transform AA to ethane by electrochemical conversion with ~82 (±5)% selectivity. The obtained results demonstrate that RuO2/TiOx exhibits an efficient electrochemical performance at low temperatures (5℃), and can convert AA at various pH, current density, and different concentrations. Moreover, we mimicked the complex chemical environment of the pyroligneous acid by adding diverse hydrocarbons (e.g., phenols, aldehydes) in acid solution to evaluate the stability of RuO2/TiOx. The electrolysis was also conducted in original pyroligneous acid solution, in which the RuO2/TiOx exhibits a considerable performance to convert AA to ethane. This work, based on the selective production of ethane from AA by a RuO2/TiOx electrode as an alternative to bulk metals as anodes for oxidative upgrading of carboxylic acids, making it promise to directly turn biomass residual into fuel thus improve the biomass utilization.

Phytoremediation as a viable ecological and socioeconomic management strategy.

Phytoremediation is an environmentally friendly alternative to traditional remediation technologies, notably for soil restoration and agricultural sustainability. This strategy makes use of marginal areas, incorporates biofortification processes, and expands crop alternatives. The ecological and economic benefits of phytoremediation are highlighted in this review. Native plant species provide cost-effective advantages and lower risks, while using invasive species to purify pollutants might be a potential solution to the dilemma of not removing them from the new habitat. Thus, strict management measures should be used to prevent the overgrowth of invasive species. The superior advantages of phytoremediation, including psychological and social improvements, make it a powerful tool for both successful cleanup and community well-being. Its ability to generate renewable biomass and adapt to a variety of uses strengthens its position in developing the bio-based economy. However, phytoremediation faces severe difficulties such as complex site circumstances and stakeholder doubts. Overcoming these challenges necessitates a comprehensive approach that balances economic viability, environmental protection, and community welfare. Incorporating regulatory standards such as ASTM and ISO demonstrates a commitment to long-term environmental sustainability, while also providing advice for unique nation-specific requirements. Finally, phytoremediation may contribute to a pleasant coexistence of human activity and the environment by navigating hurdles and embracing innovation.

ADVANCING SUSTAINABLE RESOURCE UTILISATION: A REVIEW OF AQUATIC BIOREFINERIES

This review explores the transformative potential of aquatic biorefineries in advancing sustainable resource utilisation. As global demands for renewable resources intensify, biorefineries have emerged as versatile solutions. Focusing on aquatic environments, this paper delves into diverse biomass resources, encompassing microorganisms, algae and aquatic plants. It navigates through key biorefinery processes, including hydrothermal liquefaction, algae cultivation and enzymatic conversion, illuminating their roles in sustainable biofuel and high-value chemical production. Thermochemical conversion processes, such as pyrolysis and gasification, offer additional pathways for bio-based product generation. The review critically assesses challenges in these processes, ranging from technical intricacies to regulatory considerations. Examining products derived from aquatic biorefineries (i.e. biofuels, chemicals and biomaterials) underscores their versatility. Looking ahead, the paper identifies technical challenges, regulatory landscapes and emerging technologies as focal points for future research. The review concludes by envisioning aquatic biorefineries as key players in sustainable resource management, advocating for research and technological innovation to propel this transformative field into the mainstream of the bio-based economy.

THE SIGNIFICANCE OF BIOMASS IN ACHIEVING A GLOBAL BIOECONOMY

This manuscript explores the imperative role of biomass in shaping the global bioeconomy, necessitated by escalating energy demands and the consequent environmental challenges posed by fossil fuel dependency. This paper delineates the diverse forms of biomass — from lignocellulosic materials to organic waste and algae — each holding distinct chemical compositions and applications within the bioeconomy. Investigating biomass conversion technologies (i.e. thermochemical, biochemical and chemical) provides a comprehensive understanding of their merits and limitations in energy production and resource optimisation. Specifically, it delves into pyrolysis, gasification, hydrothermal liquefaction, torrefaction, anaerobic digestion and transesterification, elucidating their mechanisms and contributions to energy generation and biofuel production. Moreover, the study incorporates bibliometric analysis, depicting thematic clusters in biomass research and highlighting the evolving trends in its application within the bioeconomy. The primary focus of studies within the initial cluster revolves around utilising biomass for a global bioeconomy through thermochemical conversion methods. Overall, this review underscores the indispensable role of biomass as a renewable and adaptable resource, pivotal in steering the transition towards a sustainable bio-based economy amid global environmental and socio-economic challenges.

New approaches for solubilization of phosphate rocks through solid-state fermentation by optimization of oxalic acid production

This study explores the enhancement of phosphate rock (PR) solubilization through solid-state fermentation (SSF) by optimizing oxalic acid production using Aspergillus niger. Key process parameters, including the use of agro-industrial by-products (sugarcane bagasse (SCB), wheat bran (WB), soybean bran (SB)), pH levels, sucrose supplementation, and methanol addition, were systematically evaluated through sequential experimental designs. The results identified SCB and SB in a 1:1 ratio as the most effective substrate. Remarkably, the inclusion of methanol (7 %) and sucrose (0.5 %) resulted in a 3-fold increase in oxalic acid production. Under these optimized conditions, significant phosphorus solubilization of Bayóvar, Itafós, and Registro PRs was achieved, with Bayóvar rock releasing up to 12.1 g/kgds of soluble P (63.8 % efficiency). Additionally, the SSF process effectively released organic phosphorus from the agro-industrial substrates. These findings hold promise for advancing the bio-based economy and developing future industrial biofertilizers.

Regional variations in the chemical composition of fresh and composted beach wrack on the island of Gotland, Sweden – Considering future treatments

Harvesting beach wrack biomass (stranded seaweed) from coastal zones to use in agriculture could mitigate eutrophication while contributing to resource substitution of fossil-based inputs in food production. As such, beach wrack holds great resource potential in a bio-based circular economy, but its chemical properties prove challenging, and more research is required to develop treatment techniques that will allow the realization of such a system. We compiled results from chemical analyses of fresh beach wrack conducted 2012–2023 from a database within the marine policy scheme LOVA in Gotland, Sweden, to study spatial and seasonal variations in macronutrients and cadmium (Cd) content since cadmium is a highlighted risk metal for beach wrack use. This data was complemented by sampling composted beach wrack from compost sites (passive pile treatment), including analysis of ammonium and nitrate.There was considerable variation in the chemical composition of the beach wrack depending on location and season. Fresh beach wrack from the LOVA-sampling exhibited an average C content of 17.32 %, N content of 1.24 %, P content of 0.17 %, and K content of 1.3 %, which is in line with earlier studies. Composted material also showed significant differences between locations in C, N, C/N, ammonium-N, nitrate-N, P, K and Cd.The C/N and ammonium-N/nitrate-N ratios in composted beach wrack differed significantly between different composts, indicating differences in mineralization processes and maturity.Average cadmium levels were below the EU cd-limit for biofertilisers 1,5 mg/kg DW, cd-level in fresh beach wrack (LOVA − 1,24 mg/kg), and in composted beach wrack (1,09 mg/kg DW). However, single values exceed the EU limit, and long-term effects of cadmium soil accumulation could not be ruled out.The results confirm that regional variations in beach wrack quality require investments in treatment techniques and strategies to make beach wrack usable.

Green pathways for biomass transformation: A holistic evaluation of deep eutectic solvents (DESs) through life cycle and techno-economic assessment

The utilization of renewable biomass resources to manufacture biofuels, chemicals, and materials has garnered considerable attention. Deep eutectic solvents (DESs) have surfaced as a promising instrument within the realm of biomass conversion, owing to their distinctive attributes such as biodegradability, negligible toxicity, easier fabrication, liquid-phase stability and renewability as opposed to ionic liquids (ILs). Research into DESs, particularly those derived from natural sources, is expanding to advance affordable and sustainable biomass conversion. However, the bottlenecks of DES are its limited solubility for certain biomass constituents, cost and availability. To overcome these hurdles, ongoing research and technological innovations strive to tap into the complete potential of DESs in biomass conversion. This review underscores the importance of evaluating DESs' eco-friendly potential comprehensively, encompassing ecological, financial, and technological standpoints which aims to illuminate how DESs can effectively contribute to sustainable biomass utilization, fostering an environmentally conscious circular bio-based economy.

Co-composting to close the cycle of resources during rose cultivation in Kenya: An agronomic and pesticide residue assessment

Recycling green waste through composting is a promising practice for the transition towards a bio-based circular economy in the floricultural sector of Africa, especially for Kenya where cut flower export accounts for nearly 14 % of its total export value in 2017. Rose waste is a large waste stream, but its intrinsic properties make it challenging to recycle. Composting on commercial scale was studied on a rose farm near Lake Naivasha, (Kenya). Three mixtures were examined: (1) rose waste (RW) only, (2) 80 % RW + 20 % tomato waste and (3) 90 % RW + 10 % mature rose compost. Trapezoidal piles of approximately 4000 kg green waste were composted following the turned windrow approach, samples were taken at six occasions. The nine-month composting study, including pesticide fate assessment, showed consistent performance across tested mixtures. All mixtures resulted in mature and stable compost with C/N ratios below 10 and a high fertilizing potential, meeting international sanitation requirements. Final average volume reduction was 82 %, total N values ranged between 8.1 and 8.9 mg g−1 compost and pH values were alkaline (8.0–8.3). Out of the approximately 50 pesticides commonly used in rose cultivation only 8–12 pesticides could be detected in the matured composts with the highest contribution of flubendiamide and fluopyram. Scenario analysis showed the feasibility of closing the resource cycle in the African floricultural sector via continuous crop rotation over eight years with an amendment rate of 11.5 kg per m2. Overall, this study provided straightforward implementable practices for rose waste management, which facilitates the re-use of valuable green waste in Africa and thereby contributes to the transition towards a global circular economy.

An Overview on Bioeconomy in Agricultural Sector, Biomass Production, Recycling Methods, and Circular Economy Considerations

This review examines the essential components of a circular economy (CE) in relation to the agricultural sector. The bioeconomy and circular economy are crucial for sustainable global industrial growth, focusing on closed-loop systems. The sustainability debate centers on intergenerational equity and natural capital. The CE requires new environmental technologies and global coordination in order to combat climate change and biodiversity loss. In addition, efficient food production and waste reduction are essential due to population growth. However, biomass is vital for a bio-based economy, impacting food waste and climate change. Grasslands support sustainable dairy production and carbon sequestration. Thus, effective waste and wastewater management are critical, with biomass energy providing renewable alternatives. Nonetheless, biofuels remain key for sustainability, focusing on pollution control and Green Chemistry. It is well known that sustainable transportation relies on bioenergy, with ongoing research improving processes and discovering new fuels. One notable challenge is managing heavy metals in biofuel production, and this underscores the need for eco-friendly energy solutions. The main purpose for this review paper is to create a connection between circular economy aspects and the agricultural system, with focus on the following: bioeconomy research, biomass utilities, and biofuel production. Extensive research was performed on the specialized literature by putting in common the main problems. Key subjects in this paper include the use of biomass in agriculture, the problems of plastic recycling, and the function of the CE in mitigating climate change and biodiversity loss. Efficient food production and waste minimization are highlighted due to their relevance in a growing population. The study’s detailed research and discussion aim to give important insights into how these practices might promote economic development and sustainability. Furthermore, the study covers important waste management issues such as food waste, plant composting, and chemical waste neutralization. These topics are critical to understanding the circular economy’s broader implications for minimizing environmental damage and implementing sustainable waste management strategies.

Biodegradation of PHB/PBAT films and isolation of novel PBAT biodegraders from soil microbiomes

Polyhydroxyalkanoates (PHAs) are important candidates for replacing petroleum-based plastics. This transition is urgent for the development of a biobased economy and to protect human health and natural ecosystems. PHAs are biobased and biodegradable polyesters that when blended with other polymers, such as poly(butylene adipate-co-terephthalate) (PBAT), acquire remarkable improvements in their properties, which allow them to comply with the requirements of packaging applications. However, the biodegradation of such blends should be tested to evaluate the impact of those polymers in the environment. For instance, PBAT is a compostable aliphatic-aromatic copolyester, and its biodegradation in natural environments, such as soil, is poorly studied. In this work, we evaluated the biodegradation of a bilayer film composed of PHB and PBAT, by a soil microbiome.The bilayer film reached 47 ± 1 % mineralization in 180 days and PHB was no longer detected after this period. The increased crystallinity of the PBAT residue was a clear sign of biodegradation, indicating that the amorphous regions were preferentially biodegraded. Seven microorganisms were isolated, from which 4 were closely related to microorganisms already known as PHB degraders, but the other 3 species, closely related to Streptomyces coelicoflavus, Clonostachys rosea and Aspergillus insuetus, were found for the first time as PHB degraders. Most remarkably, two fungi closely related to Purpureocillium lilacinum and Aspergillus pseudodeflectus (99.83 % and 100 % identity by ITS sequencing) were isolated and identified as PBAT degraders. This is very interesting due to the rarity of isolating PBAT-degrading microorganisms.These results show that the bilayer film can be biodegraded in soil, at mesophilic temperatures, showing its potential to replace synthetic plastics in food packaging.

Methanol as a co-substrate with CO2 enhances butyrate production in microbial electrosynthesis

Methanol is a promising feedstock for the bio-based economy as it can be derived from organic waste streams or produced electrochemically from CO2. Acetate production from CO2 in microbial electrosynthesis (MES) has been widely studied, while more valuable compounds such as butyrate are currently attracting attention. In this study, methanol was used as a co-substrate with CO2 to enhance butyrate production in MES. Feeding with CO2 and methanol resulted in the highest butyrate production rates and titres of 0.36 ± 0.01 g L−1 d−1 and 8.6 ± 0.2 g L−1, respectively, outperforming reactors with only CO2 feeding (0.20 ± 0.03 g L−1 d−1 and 5.2 ± 0.1 g L−1, respectively). Methanol acted as electron donor and as carbon source, both of which contributed ca. 50% of the carbon in the products. Eubacterium was the dominant genus with 52.6 ± 2.5% relative abundance. Thus, we demonstrate attractive route for the use of the C1 substrates, CO2 and methanol, to produce mainly butyrate.Key points• Butyrate was the main product from methanol and CO2in MES• Methanol acted as both carbon and electron source in MES• Eubacterium dominating microbial culture was enriched in MESGraphical