Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
3.8
3.3
Journals
Fermentation
Special Issues
Biofuels Production and Processing Technology, 3rd Edition
share announcement

Biofuels Production and Processing Technology, 3rd Edition

A special issue of Fermentation (ISSN 2311-5637). This special issue belongs to the section "Industrial Fermentation".

Deadline for manuscript submissions: 31 May 2025 | Viewed by 13242

Special Issue Editor

Dr. Alessia Tropea

E-Mail Website
Guest Editor
Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina, Italy
Interests: microbial fermentation; fermentation process management; biofuel; biorefinery; value-added products; microbial pigments production; microbial carotenoids; functional food
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The negative global warming impact and global environmental pollution due to fossil fuels mean that the main challenge of modern society is finding alternatives to conventional fuels. In this scenario, biofuels derived from renewable biomass represent the most promising renewable energy sources. Depending on the biomass used by fermentation technologies, it is possible to obtain first-generation biofuels produced from food crops, second-generation biofuels produced from non-food feedstocks (mainly originating from renewable lignocellulosic biomasses), and third-generation biofuels (represented by algae or food waste biomass).

Although biofuels appear to be the closest alternative to fossil fuels, it is necessary for them to be produced in competitive quantities and costs, requiring both improvements to production technologies and diversification of feedstock.

This topic represents an interesting challenge for both the scientific and industrial world, and many efforts are still required in this field in order to reduce the negative global warming impact and global environmental pollution due to fossil fuels, in accordance with environmentally sustainable development.

This Special Issue will focus on the development of new technologies and the implementation of new feedstock suitable for biofuels production, as well as different biomass pretreatments, fermentation strategies, different applied microorganisms used as monoculture or coculture, and different setups for biofuel fermentation processes. Moreover, research on economic feasibility is also encouraged.

Therefore, I would like to invite authors to submit original innovative research articles and review papers related to the potential topics of the “Biofuels Production and Processing Technology, 3rd Edition” Special Issue. The previous two editions can be viewed at:

Biofuels Production and Processing Technology

Biofuels Production and Processing Technology: 2nd Edition

Dr. Alessia Tropea
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Fermentation is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2100 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • biofuel production technologies
  • downstream processing
  • upstream processing
  • biorefinery
  • energy
  • bioethanol production
  • agroforest and industrial waste feedstock valorization
  • microorganisms for biofuel
  • sustainability

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • Reprint: MDPI Books provides the opportunity to republish successful Special Issues in book format, both online and in print.

Further information on MDPI's Special Issue policies can be found here.

Published Papers (6 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

14 pages, 3828 KiB  
Article
pH-Dependent Metabolic Regulation in Clostridium ljungdahlii During CO Fermentation
by Ze-Rong Liu, Zhi-Qiong Wen, Jing-Wen Wu, Hui-Peng Gao, Quan Zhang, Lan-Peng Li, Li-Cheng Liu, Qiang Li, Fu-Li Li and Zi-Yong Liu
Fermentation 2025, 11(3), 154; https://doi.org/10.3390/fermentation11030154 - 19 Mar 2025
Viewed by 538
Abstract
Clostridium ljungdahlii is a model acetogenic bacterium utilized for ethanol production from syngas, with its growth and ethanol synthesis being profoundly influenced by fermentation pH. However, the mechanistic basis of this pH-dependent regulation remains poorly understood. In this study, we systematically investigated the [...] Read more.
Clostridium ljungdahlii is a model acetogenic bacterium utilized for ethanol production from syngas, with its growth and ethanol synthesis being profoundly influenced by fermentation pH. However, the mechanistic basis of this pH-dependent regulation remains poorly understood. In this study, we systematically investigated the impact of pH on the growth and metabolic profile of C. ljungdahlii under controlled pH conditions using CO as the sole carbon and energy source. At pH 6.0, C. ljungdahlii consumed around 6.0 M carbon monoxide, producing 413 ± 43 mM acetate, 288 ± 35 mM ethanol, and 17 ± 2 mM 2,3-butanediol, with a maximum optical density (OD) of 15.9. In contrast, at pH 5.3, the strain exhibited enhanced metabolic activity, consuming around 9.6 M carbon monoxide and generating 235 ± 24 mM acetate, 756 ± 26 mM ethanol, 38 ± 4 mM 2,3-butanediol, and 28 ± 7 mM lactate, achieving a maximum OD of 30. This represents an approximate twofold increase in both ethanol production and biomass accumulation compared to pH 6.0. Proteomic and parallel reaction monitoring (PRM) analyses demonstrated that the expression levels of key enzymes in central metabolic pathways were marginally higher at pH 6.0 than at pH 5.3, indicating that the observed physiological enhancements were not attributable to differential enzyme expression but likely stemmed from variations in ATP synthesis efficiency. Further optimization experiments revealed that the optimal pH for growth and ethanol production by C. ljungdahlii under CO-sufficient and nutrient-replete conditions is approximately 5.3. These findings provide critical insights into the pH-dependent metabolic regulation of C. ljungdahlii and establish essential parameters for scaling up syngas fermentation for ethanol production. Additionally, this study offers a foundation for further exploration of the unique proton motive force-driven ATP synthesis system in C. ljungdahlii and its broader implications for metabolic network regulation. Full article
(This article belongs to the Special Issue Biofuels Production and Processing Technology, 3rd Edition)
►▼ Show Figures

Figure 1

23 pages, 4379 KiB  
Article
Simultaneous Saccharification and Fermentation of Wheat Starch for Bioethanol Production
by Vesna Vučurović, Aleksandra Katanski, Damjan Vučurović, Bojana Bajić and Siniša Dodić
Fermentation 2025, 11(2), 80; https://doi.org/10.3390/fermentation11020080 - 6 Feb 2025
Cited by 1 | Viewed by 1763
Abstract
Bioethanol is a renewable, environmentally-friendly biofuel conventionally produced through the alcoholic fermentation of sugary or starch-rich substrates by microorganisms, commonly Yeast Saccharomyces cerevisiae. Intermediates of industrial wheat flour wet milling processing to starch, such as A-starch and B-starch milk, are cost-effective, abundant, [...] Read more.
Bioethanol is a renewable, environmentally-friendly biofuel conventionally produced through the alcoholic fermentation of sugary or starch-rich substrates by microorganisms, commonly Yeast Saccharomyces cerevisiae. Intermediates of industrial wheat flour wet milling processing to starch, such as A-starch and B-starch milk, are cost-effective, abundant, and non-seasonal feedstocks for bioethanol production. This study evaluates the bioethanol production from wheat A-starch and B-starch milk and mixtures of these two substrates in different ratios (1:3, 1:1, and 3:1) using two cold hydrolysis procedures at 65 °C: (i) simultaneous liquefaction and saccharification (SLS) followed by fermentation, and (ii) liquefaction by alpha-amylase followed by simultaneous saccharification and fermentation (SSF). The results demonstrated that SSF and SLS are equally efficient procedures for reaching a high ethanol yield of 53 g per 100 g of starch and 93% of starch conversion to ethanol for all investigated substrates. Lower levels of non-starch components in A-starch milk, which typically contribute to volatile by-product formation, allowed clear distillate profiles in terms of and lower content of aldehydes, methanol, and volatile acidity, enhancing ethanol distillate purity compared to B-starch milk. Mixing high-quality A-starch milk with low-cost B-starch milk enables higher ethanol yield, improved distillate quality, and energy savings for efficient industrial-scale applications. Full article
(This article belongs to the Special Issue Biofuels Production and Processing Technology, 3rd Edition)
►▼ Show Figures

Graphical abstract

12 pages, 1303 KiB  
Article
The Effect of Hydrogen Peroxide on Biogas and Methane Produced from Batch Mesophilic Anaerobic Digestion of Spent Coffee Grounds
by Siham Sayoud, Kerroum Derbal, Antonio Panico, Ludovico Pontoni, Massimiliano Fabbricino, Francesco Pirozzi and Abderrezzaq Benalia
Fermentation 2025, 11(2), 60; https://doi.org/10.3390/fermentation11020060 - 29 Jan 2025
Viewed by 1122
Abstract
This paper aims to explore both experimental and modeling anaerobic digestion (AD) processes as innovative methods for managing the substantial quantities of spent coffee grounds (SCG) generated in Algeria, transforming them into valuable renewable energy sources (biogas/methane). AD of SCG, while promising, is [...] Read more.
This paper aims to explore both experimental and modeling anaerobic digestion (AD) processes as innovative methods for managing the substantial quantities of spent coffee grounds (SCG) generated in Algeria, transforming them into valuable renewable energy sources (biogas/methane). AD of SCG, while promising, is hindered by its complex lignocellulosic structure, which poses a significant challenge. This study investigates the efficacy of hydrogen peroxide (H2O2) pretreatment in addressing this issue, with a particular focus on enhancing biogas and methane production. The AD of SCG was conducted over a 46-day period, and the impact of H2O2 pretreatment was evaluated using laboratory-scale batch anaerobic reactors. Four different concentrations of H2O2 (0.5, 1, 2, and 4% H2O2 w/w) were studied in mesophilic conditions (37 ± 2) for 24 h at room temperature, providing basic data on biogas and methane production. The results showed a significant increase in soluble oxygen demand (SCOD) and total sugar solubilization in the range of 555.96–713.02% and 748.48–817.75%, respectively. The optimal pretreatment was found to be 4% H2O2 w/w resulting in 16.28% and 16.93% improvements in biogas and methane yield over the untreated SCG. Further, while previous research has established oxidative pretreatment efficacy, this study uniquely combines the empirical analysis of H2O2 pretreatment with a detailed kinetic modeling approach using the modified Gompertz (MG) and logistic function (LF) models to estimate kinetic parameters and determine the accuracy of fit. The MG model showed the most accurate prediction, thus making the present investigation a contribution to understanding the performance of the AD system under oxidative pretreatment and designing and scaling up new systems with predictability. These findings highlight the potential of H2O2-pretreated SCG as a more efficient and readily available resource for sustainable waste management and renewable energy production. Full article
(This article belongs to the Special Issue Biofuels Production and Processing Technology, 3rd Edition)
►▼ Show Figures

Figure 1

25 pages, 2105 KiB  
Article
Co-Digestion and Mono-Digestion of Sewage Sludge and Steam-Pretreated Winter Wheat Straw in Continuous Stirred-Tank Reactors—Nutrient Composition and Process Performance
by Emma Kreuger, Virginia Tosi, Maja Lindblad and Åsa Davidsson
Fermentation 2024, 10(8), 414; https://doi.org/10.3390/fermentation10080414 - 10 Aug 2024
Viewed by 1448
Abstract
Wheat straw (WS) constitutes a considerable biomass resource and can be used to produce the energy carrier methane through anaerobic digestion. Due to the low contents of several nutrient elements and water in harvested WS, the use of sewage sludge (SS), consisting of [...] Read more.
Wheat straw (WS) constitutes a considerable biomass resource and can be used to produce the energy carrier methane through anaerobic digestion. Due to the low contents of several nutrient elements and water in harvested WS, the use of sewage sludge (SS), consisting of primary sludge and waste-activated sludge, as a nutrient source in co-digestion with steam-pretreated wheat straw (PWS) was investigated theoretically and practically. WS was steam-pretreated, with acetic acid as the catalyst, at 190 °C for 10 min, ending with a rapid reduction in pressure. Process stability and specific methane production were studied for the mono-digestion and co-digestion of PWS and SS in continuous stirred-tank reactors for 208 days. The HRT was 22 days and the OLR 2.1 gVS L−1 d−1. In co-digestion, the OLR was increased to 2.8 gVS L−1 d−1 for one week. Nutrient elements were added to PWS mono-digestion at two different concentration levels. Co-digestion was stable, with a total concentration of short-chain fatty acids (SCFAs) at a safe level below 0.35 g L−1 at both OLRs. The higher OLR during co-digestion would require an increase in reactor volume of 14%, compared to the mono-digestion of SS, but would increase the annual production of methane by 26%. The specific methane production levels for PWS mono-digestion, SS mono-digestion, and co-digestion were 170, 320, and 260 mL g−1VS, respectively. Co-digestion did not result in a synergistic increase in the methane yield. SCFAs accumulated in the mono-digestion of PWS when using lower levels of nutrient supplements, and the concentrations fluctuated at higher nutrient levels. The main conclusion is that PWS and SS can be co-digested with long-term process stability, without the addition of chemicals other than water and acetic acid. The specific methane production for mono-digestion of PWS was relatively low. The effect of using higher concentrations of micronutrients in PWS mono-digestion should be evaluated in future studies. Full article
(This article belongs to the Special Issue Biofuels Production and Processing Technology, 3rd Edition)
►▼ Show Figures

Figure 1

12 pages, 1329 KiB  
Article
Enhancing the Fermentation Process in Biogas Production from Animal and Plant Waste Substrates in the Southeastern Region of Bulgaria
by Angel Terziev, Penka Zlateva and Martin Ivanov
Fermentation 2024, 10(4), 187; https://doi.org/10.3390/fermentation10040187 - 29 Mar 2024
Cited by 3 | Viewed by 4290
Abstract
Annually, a huge amount of waste from plant biomass and animal manure is produced from agriculture and animal farming. Many studies provide information on the biomethane potential of agricultural and livestock wastes, but only a few studies have investigated the application of the [...] Read more.
Annually, a huge amount of waste from plant biomass and animal manure is produced from agriculture and animal farming. Many studies provide information on the biomethane potential of agricultural and livestock wastes, but only a few studies have investigated the application of the substrates in combination. The objective of the study is to enhance the fermentation process in the digester for biogas production, obtained from animal and plant waste substrates. In four batch processes for three months, the temperatures and the residence time of the substrates in the fermenter were analyzed. Simultaneously, electricity and thermal energy were produced via cogeneration units, which were exported to the public grid and city heating network. The plant substrate is a silage mixture of corn and wheat waste. The animal substrate is a mixture of beef and pig manure. Animal and vegetable waste raw materials are collected and transported to the site, located in the region of southeastern Bulgaria. The total annual consumption of animal and plant waste is 17,971 t/year. The enhancement of the process leads to the production of 1,506,000 Nm3 CH4/a of methane, the generation of which requires 299.63 MWh/a of electricity and 649.09 MWh/a thermal energy. Full article
(This article belongs to the Special Issue Biofuels Production and Processing Technology, 3rd Edition)
►▼ Show Figures

Figure 1

25 pages, 4924 KiB  
Article
Bioethanol Production from A-Starch Milk and B-Starch Milk as Intermediates of Industrial Wet-Milling Wheat Processing
by Aleksandra Katanski, Vesna Vučurović, Damjan Vučurović, Bojana Bajić, Žana Šaranović, Zita Šereš and Siniša Dodić
Fermentation 2024, 10(3), 144; https://doi.org/10.3390/fermentation10030144 - 2 Mar 2024
Cited by 3 | Viewed by 3645
Abstract
The present work highlights the advances of integrated starch and bioethanol production as an attractive industrial solution for complex wheat exploitation to value-added products focusing on increased profitability. Bioethanol is conventionally produced by dry-milling wheat grain and fermenting sugars obtained by the hydrolysis [...] Read more.
The present work highlights the advances of integrated starch and bioethanol production as an attractive industrial solution for complex wheat exploitation to value-added products focusing on increased profitability. Bioethanol is conventionally produced by dry-milling wheat grain and fermenting sugars obtained by the hydrolysis of starch, while unused nonfermentable kernel compounds remain in stillage as effluents. On the other hand, the wet-milling of wheat flour enables complex wheat processing for the simultaneous production of starch, gluten, and fiber. The intermediates of industrial wheat starch production are A-starch milk, containing mainly large starch granules (diameter > 10 μm), and B-starch milk, containing mainly small starch granules (diameter < 10 μm). The present study investigates different starch hydrolysis procedures using commercial amylase for bioethanol production from A-starch and B-starch milk by batch fermentation using distillers’ yeast Saccharomyces cerevisiae Thermosacc®. Cold hydrolysis with simultaneous liquefaction and saccharification at 65 °C, a pH of 4.5, and a duration of 60 min was the most efficient and energy-saving pretreatment reaching a high conversion rate of starch to ethanol of 93% for both of the investigated substrates. A process design and cost model of bioethanol production from A-starch and B-starch milk was developed using the SuperPro Designer® v.11 (Intelligen Inc., Scotch Plains, NJ, USA) software. Full article
(This article belongs to the Special Issue Biofuels Production and Processing Technology, 3rd Edition)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-6
Back to TopTop