Biomass & Bioenergy最新文献

{"title":"Assessment of long-lived Carbon permanence in agricultural soil: Unearthing 15 years-old biochar from long-term field experiment in vineyard","authors":"David Chiaramonti ,&nbsp;Giulia Lotti ,&nbsp;Francesco Primo Vaccari ,&nbsp;Hamed Sanei","doi":"10.1016/j.biombioe.2024.107484","DOIUrl":"10.1016/j.biombioe.2024.107484","url":null,"abstract":"<div><div>Carbon persistence in soil is a key issue in the context of Carbon Dioxide Removal (CDR) policies and regulations: Soil Carbon Accumulation (SCA) is also included in the latest EU regulations on sustainable biofuels, and gaining attention at international level within ICAO and IMO. The long-lived nature of the durable carbon share in biochar can meet the most sever criteria set by relevant and ambitious CDR policies: however, the possibility to quantitatively assess the persistent carbon fraction in biochar has been highly debated in recent years. While lab-scale incubation experiments are intrinsically limited in providing information on long-term permanence, they do not address actual farm-scale persistence under real cultivation management practices. The deployment and combined use of recent analytical techniques allows instead to identify and quantitatively assess the persistence of the durable carbon fractions in biochar, and thus compliance of this carbon removal with the targets of CDR policies. The present work builds on one of the longest, almost unique, biochar experiments in the EU, originally developed for assessing the agronomic performances of biochar amended agricultural soil: for the first time, biochar distributed in a vineyard soil at 22 t/ha scale in 2009 was unearthed in 2024 and collected for full characterization. The agricultural soil was subject to conventional agricultural practices over the 15 years of vineyard cultivation. The scope of this research is to assess the permanence of biochar under these conditions. The present work shows the complexity of unearthing biochar from soil, applying a focused method to recover and clean the material before its characterization, without altering its chemical and physical properties. Both unearthed and original (i.e. before deployment) biochars were washed with water under same condition and procedures, and fully characterized. In addition to analytical practices commonly adopted for biochar characterization, FT-IR, SEM EDX, and Random Reflectance (R_o) techniques were used, quantifying the amount of the inertinite carbon component in biochar. Despite the dilution from the inclusion of exogeneous organic and inorganic matter from soil in the original biochar, the ratio of fixed carbon (Cfix) to total carbon (Ctot) showed minor variations (∼8 %). Moreover, the inertinite and semi-inertinite fractions in the washed original and unearthed biochars remained almost unchanged over 15 years of active use in agricultural soil, confirming the permanent nature of the inertinite share of carbon in biochar. This result, together with other recent findings in literature, provides scientific evidence supporting Biochar Carbon Removals (BCRs) as permanent removal in Carbon Dioxide Removal (CDR) regulations.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107484"},"PeriodicalIF":5.8,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved bioethanol production from corn stover using microwave-assisted protic ionic liquid pretreatment and an engineered S. cerevisiae strain","authors":"Yankun Wang ,&nbsp;Changsheng Su ,&nbsp;Xueying Mei ,&nbsp;Yongjie Jiang ,&nbsp;Yilu Wu ,&nbsp;Afrouz Khalili ,&nbsp;Hamid Amiri ,&nbsp;Changwei Zhang ,&nbsp;Di Cai ,&nbsp;Peiyong Qin","doi":"10.1016/j.biombioe.2024.107486","DOIUrl":"10.1016/j.biombioe.2024.107486","url":null,"abstract":"<div><div>Construction of a green, economical, and energy-efficient lignocellulose pretreatment process is the core to improve the economic feasibility of the second-generation bioethanol production. This study presents an effective strategy for bioethanol production based on microwave-assisted Diisopropylammonium hydrosulfate ([DIP][HSO₄]) pretreatment. The mechanisms for the depolymerization of the lignocellulose matrix in the novel pretreatment process were proposed by characterize the fractionated pulp and lignin. In this process, the effect of microwave power on mono-sugars production was also investigated. Results indicated that substantial removal of hemicellulose and lignin by 63.75 wt% and 59.36 wt %, respectively, were realized at 170 W for 3 min, which afforded to 69.69 % and 73.78 % of glucan and xylan recoveries in subsequent saccharification. Ethanol fermentation performances of the enzymatic hydrolysate of the pretreated pulps were evaluated using a C5/C6 co-assimilation <em>Saccharomyces cerevisiae</em> YL23. 34.35 g L⁻¹ of ethanol with a yield of 0.42 g g⁻¹ (total monomer sugars in hydrolysate) was received in the end fermentation broth using the fed-batch hydrolysate containing total 80.88 g L⁻¹ of mono-sugars. Correspondingly, 12.01 g of bioethanol and 13.12 g of technical lignin were co-generated from 100 g of dried corn stover.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107486"},"PeriodicalIF":5.8,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization and pilot-scale downdraft gasification of invasive forestry species biomass in the Dominican Republic","authors":"Rafael Vásquez-Martínez ,&nbsp;Julián Cuervo ,&nbsp;Pascual A. Ramos ,&nbsp;Yessica A. Castro","doi":"10.1016/j.biombioe.2024.107476","DOIUrl":"10.1016/j.biombioe.2024.107476","url":null,"abstract":"<div><div>In many developing countries, the primary source of energy generation is fossil fuels. However, the study and utilization of invasive forestry species for gasification can help transition away from fossil fuels and towards sustainable, renewable energy production. In the present work, we investigated the characterization and energy potential of four invasive forestry species (<em>Prosopis juliflora, Azadirachta indica, Acacia mangium,</em> and <em>Calliandra calothyrsus</em>) affecting the dry and rain forests of the Dominican Republic. We analyzed the parts (wood, bark, and branches), and transverse diameter sizes (less than 2.5 cm, 2.5–5.0 cm, and 5.0 cm) of the invasive forestry species. Additionally, we evaluated the calorific value, composition, and quality indicators of the syngas produced by these species using a downdraft gasifier. Fixed carbon, ash, and moisture content were higher in the bark compared to the wood and branches of the forestry species. Also, lower the thickness of the species branches tended to have higher moisture and ash content. <em>A. mangium</em> had the highest energy potential with calorific values of 20.4 MJ/kg for the biomass and 5.22 MJ/m³ for the syngas. The species <em>P. juliflora</em> showed a calorific value of 18.6 MJ/kg and syngas with 5.08 MJ/m³. However, the gasifier cold gas efficiency of the species <em>P. juliflora</em> obtained of 24.89 % which was slightly higher than <em>A. mangium</em> with 23.29 % based on the conversion ratio of biomass to gas. Our findings reveal the promising potential of <em>P. juliflora</em>, a relatively underexplored biomass, as a viable feedstock for gasification-based bioenergy production.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107476"},"PeriodicalIF":5.8,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Piezoresistivity in pyrolyzed coconut fiber","authors":"Mohammed Mudassir ,&nbsp;Bushair Ali K ,&nbsp;Ali Ahmadian ,&nbsp;C.N. Shyam Kumar","doi":"10.1016/j.biombioe.2024.107479","DOIUrl":"10.1016/j.biombioe.2024.107479","url":null,"abstract":"<div><div>Pyrolyzed carbon materials give fascinating solutions for many problems in the current research world. The locally available organic wastes can be pyrolyzed and tuned for their properties for various applications. Coconut-based materials such as shell and fiber have shown promising results in different technological applications. However, a detailed study of the structural and property evolution of these materials has not been carried out yet. In this work, the evolution of conductivity and piezoresistivity of coconut fiber-derived carbon is studied. Coconut fiber is pyrolyzed at different temperatures 600 °C, (CCP600) 800 °C (CCP800) and 1000 °C (CCP1000) to produce carbon fiber. Electrical conductivity experiments show differences between CCP600, CCP800 and CCP1000, with CCP600 displaying much lower conductivity at approximately (0.7 S/m) compared to CCP800 (1 × 10³ S/m) and CCP1000 (1.4 × 10³ S/m). Conversely, CCP600 demonstrates impressive piezoresistive characteristics, exhibiting significant resistance changes even under minimal strain. The gauge factor for the coconut fiber-derived carbon was found to be 4.1 for CCP600, 1.0 for CCP800, and 0.3 for CCP1000. Further, the powdered carbon samples show an increase in the gauge factor to a range of 36.8, which makes CCP600 well-suited for sensor applications requiring precise sensing capabilities. The present study suggests that CCP600, with its low cost and ease of fabrication, is a promising material for low-budget sensor applications.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107479"},"PeriodicalIF":5.8,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving in-situ biomethanation of sewage sludge under mesophilic conditions: Performance and microbial community analysis","authors":"Mohamed Saad Hellal ,&nbsp;Filip Gamon ,&nbsp;Grzegorz Cema ,&nbsp;Kishore Kumar Kadimpati ,&nbsp;Aleksandra Ziembińska-Buczyńska ,&nbsp;Joanna Surmacz-Górska","doi":"10.1016/j.biombioe.2024.107487","DOIUrl":"10.1016/j.biombioe.2024.107487","url":null,"abstract":"<div><div>This research investigated the application of in-situ biological hydrogen methanation within a continuous stirred tank reactor (CSTR) system under mesophilic conditions, with sewage sludge used as the substrate. Two CSTRs with an effective capacity of 5 L were installed and loaded with inoculum sludge with a volatile solid (VS) concentration of 1.2–1.5 %. They were fed mixed waste sludge with an organic loading rate (OLR) of 1.5 g VS/L and an average sludge retention time (SRT) of 19 days under mesophilic conditions at 37 °C. One of the reactors operated as a control, while the other was injected with H₂ through a microceramic membrane diffuser with a H₂:CO₂ ratio of 4:1. The results of this study revealed that the addition of H₂ and the recirculation of residual hydrogen in biogas led to a substantial increase in the production of methane from 157 L/kg VS to 275 L/kg VS. Increasing the methane content in biogas from 52 % to 78 % yielded an impressive 42.8 % higher methane production rate. Metataxonomic analysis of the microbial community via high-throughput sequencing techniques revealed that the dominant acetoclastic and hydrogenotrophic methanogens were <em>Methanosaeta</em> and <em>Methanoregula</em>, respectively, with greater abundances of both groups in the experimental bioreactor. The dynamics of their activity in both bioreactors were analyzed via qPCR, and the functional genes encoding methyl-coenzyme M reductase (<em>mcrA</em> gene) and hydrogenase Ni-Fe presented comparable changes between RI and RII. By optimizing key operational parameters and closely examining the dynamics of the microbial community, this approach can contribute significantly to sustainable bioenergy solutions while minimizing environmental impact.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107487"},"PeriodicalIF":5.8,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydroprocessing of waste cooking oil to produce liquid fuels over Ni-Mo and Co-Mo supported on carbon nanotubes","authors":"K.K. Ferreira ,&nbsp;C. Di Stasi ,&nbsp;A. Ayala-Cortés ,&nbsp;L.S. Ribeiro ,&nbsp;J.L. Pinilla ,&nbsp;I. Suelves ,&nbsp;M.F.R. Pereira","doi":"10.1016/j.biombioe.2024.107480","DOIUrl":"10.1016/j.biombioe.2024.107480","url":null,"abstract":"<div><div>New fuel production alternatives are becoming increasingly necessary to replace fossil energy sources and reduce the environmental implications of carbon emissions. In this context, renewable sources, such as waste cooking oil (WCO), are an excellent choice for producing bio-based fuels. However, to use WCO as fuel, the oxygen content in its triglyceride structures must be removed. To this end, bimetallic Co-Mo and Ni-Mo supported on pristine carbon nanotubes (CNT) and oxidized carbon nanotubes (CNT_ox) were synthesized to investigate the hydroprocessing of WCO in a batch reactor operating at 350 °C, 70 bar of H₂ (evaluated at ambient temperature) for 3 h. The results showed that Ni-Mo/CNT_ox exhibited superior catalytic performance, mainly producing <em>n</em>-alkanes in the range of C₁₄-C₂₂ with a carbon conversion of about 67 mol.% and being selective for light alkanes (6.6 mol.% of C₅-C₇), jet fuel (11.4 mol.% of C₈-C₁₆) and diesel fuel (81.2 mol.% of C₁₇-C₂₂). On the other hand, a residence time of 5 h was necessary to achieve the same results with the carbon-supported Co-Mo catalysts. Hydrodeoxygenation was the main deoxygenation route followed using CNT based catalysts.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107480"},"PeriodicalIF":5.8,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing hydrogen production from anaerobic digestion of pretreated fruit and vegetable peels using Clostridium butyricum NE133","authors":"N. Elerakey,&nbsp;S.M. Abdelrahman,&nbsp;M.A. Tawfik,&nbsp;A.H.M. Rasmey,&nbsp;A.A. Aboseidah,&nbsp;H. Hawary","doi":"10.1016/j.biombioe.2024.107485","DOIUrl":"10.1016/j.biombioe.2024.107485","url":null,"abstract":"<div><div>This study aimed to investigate the feasibility of hydrogen production (HP) by <em>Clostridium butyricum</em> NE133 from different fruit and vegetable peels (FVPs) as substrates. In addition, the kinetic parameters of hydrogen production and optimization of the anaerobic dark fermentation conditions were analyzed. <em>Clostridium butyricum</em> NE133 was isolated from domestic wastewater and selected as the front runner hydrogen-producer from glucose with maximum hydrogen production (H_max) of 1778.00 ± 15.03 mL/L, maximum production rate (R_max) of 961.95 mL/L/h and lag phase (λ) of 28.12 h. NE133 was genetically identified (accession number PP581793) and shown to harbor the Fe-Fe hydrogenase gene. This isolate showed a high potential to produce hydrogen from anaerobic fermentation of watermelon peels with H_max of 1062.67 ± 11.92 mL/L, R_max of 268.01 mL/L/h and λ of 33.92 h. The watermelon peels were subjected to different pretreatment methods to enhance the dark fermentation by <em>C. butyricum</em> NE133. It was revealed that the combined physicochemical treatment (0.05 M H₂SO₄/121 °C) significantly increased hydrogen yield, with 2300.33 ± 0.88 mL/L, R_max of 1065.56 mL/L/h and λ of 22.39 h with a high accuracy of R² (0.9999). The study emphasizes the effectiveness of using <em>C. butyricum</em> NE133 for sustainable biohydrogen production. The findings also indicate the feasibility of converting agricultural waste into valuable energy sources, contributing to waste management and renewable energy solutions.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107485"},"PeriodicalIF":5.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive utilization of Aspergillus niger waste mycelium based on physically induced autolysis: Preparation of chitosan and alternative nitrogen source","authors":"Qinfeng Guo ,&nbsp;Yanting Xu ,&nbsp;Zijun Liu ,&nbsp;Dandan Zhang ,&nbsp;Zhilong Xiu ,&nbsp;Yuesheng Dong","doi":"10.1016/j.biombioe.2024.107477","DOIUrl":"10.1016/j.biombioe.2024.107477","url":null,"abstract":"<div><div>In industrial fermentation of citric acid, vast quantities of mycelium from <em>Aspergillus niger</em> (MAN) are produced, with an annual output of 20 million tons in China alone. The disposal of waste MAN poses a significant challenge and signifies a missed opportunity for resource recovery. In this study, physically induced autolysis (PIA) was employed to utilize the MAN proteins and chitosan. The results indicated abundant soluble proteins and sugars were released into the supernatant, while the cell fragments can be used to prepare chitosan. Under optimized autolytic conditions, the rate of total protein utilization of MAN was 78.7 %, and the rate of reserved chitin in the cell fragment was 93.8 %, outperforming other techniques. These findings were consistently reproducible in larger-scale experiments. Chitosan was prepared from cell fragments that eliminated the need for acid treatment and reduced alkali utilization by 50–67 %, thanks to PIA's effective removal of proteins from cell fragments. The rate of total sugar utilization, including both the content of the soluble sugars from autolysate and prepared chitosan, was 75.42 % of the total sugar of MAN. Additionally, the autolysate was proved to be an alternative nitrogen source in the fermentation media for microbial production of 2, 3-butanediol and citric acid, yielding concentrations comparable or superior to traditional sources. Thus, our findings not only achieved high component utilization rates but also facilitated environmentally friendly chitosan preparation, indicating the potential for innovative approaches to convert waste mycelium into valuable resources and advance the industry towards more efficient practices.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107477"},"PeriodicalIF":5.8,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Porous and high specific surface area carbon material derived from ginkgo leaves for high-performance symmetric supercapacitors","authors":"Lihua Zhang ,&nbsp;Xiaoyang Cheng ,&nbsp;Lingyan Li ,&nbsp;Xinran Li ,&nbsp;Hao Wu ,&nbsp;Jinfeng Zheng ,&nbsp;Jiarong Yao ,&nbsp;Guifang Li","doi":"10.1016/j.biombioe.2024.107481","DOIUrl":"10.1016/j.biombioe.2024.107481","url":null,"abstract":"<div><div>Carbon materials have the advantages of large surface area, high conductivity and stable chemical properties, and are widely used in the field of electrochemical energy storage. However, carbon materials currently have some problems such as high cost, complicated process and poor electrochemical performance. The development of low cost, environmental friendly and high specific capacitance porous carbon materials is of great significance for large-scale production and application. In addition, renewable, low-cost biomass materials are ideal precursors for the preparation of porous carbon materials. In this work, porous carbon materials were synthesized using ginkgo leaves as carbon source and KHCO₃ as activator. The effect of activator mass on the structure and composition of porous carbon was studied in detail. The results show that when 3 g activator is added, the prepared carbon material (GCK-3) has a specific surface area of up to 2640 m² g⁻¹ and a rich hierarchical pore structure (including micro, medium and large pores). In addition, the carbon material retains a certain amount of the heteroatoms of the biomass itself, which can generate additional pseudocapacitance. Due to the advantages of composition and structure, GCK-3 shows good electrochemical performance and rate performance. A symmetric supercapacitor assembled from two identical GCK-3 electrodes has an energy density of 13.7 Wh kg⁻¹ and exhibits good cycle stability with a capacitor retention rate of 100 % after 10,000 cycles. The green and low-cost carbon source precursor, simple synthesis method and excellent electrochemical properties all indicate that ginkgo leaf derived carbon materials have great application prospects.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107481"},"PeriodicalIF":5.8,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can mild alkaline pretreatment simultaneously enhance the antioxidant capacity of Beta-carotene extracts and biomethane yields in a sustainable Dunaliella salina biorefinery?","authors":"Pilar Águila-Carricondo ,&nbsp;Raquel García-García ,&nbsp;Juan Pablo de la Roche ,&nbsp;Pedro Luis Galán ,&nbsp;Luis Fernando Bautista ,&nbsp;Gemma Vicente","doi":"10.1016/j.biombioe.2024.107474","DOIUrl":"10.1016/j.biombioe.2024.107474","url":null,"abstract":"<div><div>This research aims to assess the effect of alkaline pretreatments on the antioxidant potential of β-carotene-rich extracts from the microalga <em>Dunaliella salina</em> and the cumulative biomethane production from its spent biomass, within the framework of a circular economy approach using four biorefineries. A solvent screening was performed, with ethyl acetate achieving the maximum β-carotene extraction yield (5.3% ± 0.03%). Alkaline pretreatments were applied to the initial biomass (direct) and extracts after a extraction with ethyl acetate (indirect), using two matrices: water (W) and a mixture water:ethanol (WE). Direct alkaline pretreatments (D) offered extracts with higher potential than indirect pretreatments (I) in terms of: i) antioxidant capacity, as measured by ABTS^•+ assay (0.69±0.1 and 0.61±0.1 mmolTE/gDW for W-D and WE-D, respectively, and 0.55±0.1 and 0.53±0.1 mmolTE/gDW for W-I and WE-I, respectively) and •OH scavenging activity (1.89±0.2 and 2.05±0.5 mmolTE/gDW for W-D and WE-D, respectively, and 0.48±0 and 1.2±0.3 mmolTE/gDW for W-I and WE-I, respectively), ii) biomethane production from their spent biomass (301±14 mLCH₄/gVS and 289±9.0 mLCH₄/gVS for W-D and WE-D, respectively, compared to 235±57 mLCH₄/gVS without alkaline pretreatment), and iii) sustainability analysis, which includes the assessment of the biomass exploitation for β-carotene extraction and biomethane production. The most sustainable biorefinery was W-D as it achieved the highest biomass exploitation (33.8%), compared to WE-D (29.1%), W-I (33.1%) or WE-I (32.8%). This underscores the novelty and effectiveness of direct alkaline pretreatments for enhancing both antioxidant potential and energy recovery from <em>D. salina</em> biomass in a biorefinery context.</div></div>","PeriodicalId":253,"journal":{"name":"Biomass & Bioenergy","volume":"191 ","pages":"Article 107474"},"PeriodicalIF":5.8,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}