Organic Waste Valorization into Bioenergy and Biochemicals with High Industrial Interest

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

Deadline for manuscript submissions: closed (20 November 2023) | Viewed by 8463

Special Issue Editor


E-Mail Website
Guest Editor
IMDEA Energy Institute, Madrid, Spain
Interests: anaerobic digestion; anaerobic fermentation; bioenergy, bioproducts; biofuels; microalgae; organic waste valorization; microbial community analysis
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Worldwide concerns regarding fossil fuel reserve exhaustion is not only associated with energy security but also with the future availability of a wide number of compounds that are currently produced through petrochemical routes. The search for an alternative source able to replace petrochemical derivatives while promoting a sustainable development gave rise to considering organic wastes a valuable feedstock for producing energy and products. Within this approach, the valorization of organic wastes does not only help to solve environmental pollution but could also contribute to the transition from a linear to a renewable circular economy. In this regard, biological processes are considered sustainable and cost-effective technologies to valorize different kinds of organic wastes (municipal solid waste, agroindustrial wastes, lignocellulosic biomass, microalgae, food industry effluents, etc.) into biochemicals with a high industrial interest, including fatty acids, succinic acid, lactic acid, bioethanol, biopolymers, amino acids, and biohydrogen, among others.

The Special Issue will be focused on organic waste valorization via biological processes into added-value products. The main topics include but are not limited to the following:

  • New biological processes;
  • Process optimization;
  • Biofuel production;
  • Bioenergy production;
  • Green chemical production;
  • Waste valorization;
  • Product recovery;
  • Microbial analysis.

Dr. Silvia Greses
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 2600 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

  • fermentative processes
  • innovative bioprocesses
  • bioprocess optimization
  • added-value bioproducts
  • green chemicals
  • circular economy
  • organic wastes
  • microbial community

Published Papers (5 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

15 pages, 6224 KiB  
Article
The Stool Microbiome in African Ruminants: A Comparative Metataxonomic Study Suggests Potential for Biogas Production
by Felipe Werle Vogel, Nicolas Carlotto, Zhongzhong Wang, Lydia Garrido, Vasiliki Chatzi, Raquel Gonzalez Herrero, Luis Benavent-Albarracín, Javier Martinez Gimenez, Loles Carbonell and Manuel Porcar
Fermentation 2024, 10(3), 119; https://doi.org/10.3390/fermentation10030119 - 21 Feb 2024
Viewed by 1229
Abstract
Lignocellulosic biomass is a promising substrate for anaerobic digestion (AD) in renewable energy generation but presents a significant challenge during the hydrolysis stage of conventional AD due to the recalcitrant nature of this biomass substrate. Rumen fluid is often employed as a bioaugmentation [...] Read more.
Lignocellulosic biomass is a promising substrate for anaerobic digestion (AD) in renewable energy generation but presents a significant challenge during the hydrolysis stage of conventional AD due to the recalcitrant nature of this biomass substrate. Rumen fluid is often employed as a bioaugmentation seed to enhance hydrolysis in the AD of lignocellulosic substrates due to its richness in hydrolytic bacteria. However, using rumen fluid to enhance AD processes presents substantial hurdles, including the procurement difficulties associated with rumen fluid and ethical concerns. In this study, the fecal microbiota of 10 African ruminant species from a large zoological park (Bioparc) in Valencia, Spain, were studied using 16S rRNA gene amplicon sequencing. In this study, the fecal microbiota of 10 African ruminant species from a large zoological park (Bioparc) in Valencia, Spain, were studied using 16S rRNA gene amplicon sequencing. The investigation revealed potential similarities between the fecal microbiota from the African ruminants’ and cows’ rumen fluids, as suggested by theoretical considerations. Although direct comparative analysis with cow rumen fluid was not performed in this study, the theoretical framework and existing literature hint at potential similarities. According to our results, the Impala, Blesbok, Dikdik and Bongo ruminant species stood out as having the greatest potential to be used in bioaugmentation strategies. Key genera such as Fibrobacter, Methanobrevibacter, and Methanosphaera in Impala samples suggested Impala rumen fluid’s involvement in cellulose breakdown and methane production. Blesbok and Dikdik exhibited a high abundance of Bacillus and Atopostipes, potentially contributing to lignin degradation. The richness of Prevotellaceae and Rikenellaceae in the Bongo fecal samples is probably associated with structural carbohydrate degradation. Taken together, our results shed light on the microbial ecology of the gut contents of a whole set of Bovidae ruminants and contribute to the potential application of gut microbiota in AD. Full article
Show Figures

Figure 1

14 pages, 1275 KiB  
Article
Employing Spent Frying Oil as a Feedstock to Produce Short-Chain Organic Acids Using Mixed Microbial Cultures
by André Oliveira, Sílvia Petronilho and Luísa S. Serafim
Fermentation 2023, 9(11), 975; https://doi.org/10.3390/fermentation9110975 - 15 Nov 2023
Viewed by 1051
Abstract
Food industry waste and wastewater have been explored in relation to acidogenic fermentation as sources of non-competing food carbohydrates and mixed microbial cultures (MMCs), respectively, with the aim of producing short-chain organic acids (SCOAs) with general applications in polyhydroxyalkanoates (PHAs) production. However, studies [...] Read more.
Food industry waste and wastewater have been explored in relation to acidogenic fermentation as sources of non-competing food carbohydrates and mixed microbial cultures (MMCs), respectively, with the aim of producing short-chain organic acids (SCOAs) with general applications in polyhydroxyalkanoates (PHAs) production. However, studies on acidogenic fermentation using lipidic substrates are scarce. In this work, it was hypothesized that spent frying oil (SFO) could be used as a substrate for SCOA production via MMCs. In this study, oleic acid was used as a model molecule. The characterization of SFO revealed that it is mainly composed of oleic acid (81%), with minor amounts of palmitic, linoleic, and stearic acids. Different MMCs and food-to-microorganism (F/M) ratios were tested. MMCs collected in the aerobic tank of a municipal wastewater treatment plant (AES), at a 1:1 F/M, allowed to obtain the highest SCOA concentration (1.50 g COD/L) and the most diverse profile of SCOAs, with the production of acetic, propionic, butyric, iso-butyric, and valeric acids at 48:17:9:13:13% on a molar basis, respectively. This variety of odd and even SCOAs is of upmost importance, with potential applications in producing PHAs. This work can be considered a starting point for future acidogenic fermentation studies using lipid-based substrates and for the future production of PHAs. Full article
Show Figures

Figure 1

12 pages, 1491 KiB  
Article
Feasibility Study of Biohydrogen Production from Acid Cheese Whey via Lactate-Driven Dark Fermentation
by Brenda Aranda-Jaramillo, Elizabeth León-Becerril, Oscar Aguilar-Juárez, Roberto Castro-Muñoz and Octavio García-Depraect
Fermentation 2023, 9(7), 644; https://doi.org/10.3390/fermentation9070644 - 9 Jul 2023
Cited by 7 | Viewed by 2416
Abstract
The high loading of lactic acid bacteria (LAB) present in cheese whey still limits its use as hydrogen feedstock. This study aims to investigate the feasibility of producing hydrogen from acid cheese whey via lactate-driven dark fermentation (LD-DF). Mesophilic batch fermentations were performed [...] Read more.
The high loading of lactic acid bacteria (LAB) present in cheese whey still limits its use as hydrogen feedstock. This study aims to investigate the feasibility of producing hydrogen from acid cheese whey via lactate-driven dark fermentation (LD-DF). Mesophilic batch fermentations were performed with delipidated acid cheese whey at a fixed pH of 5.8 and driven by an acidogenic bacterial culture containing LAB and lactate-oxidizing hydrogen producers (LO-HPB). The results obtained indicated that it is technically feasible to produce hydrogen from undiluted cheese whey through lactate oxidation-mediated fermentation. It was elucidated that the acidogenic fermentation of cheese whey followed a two-step lactate-type fermentation, in which fermentable carbohydrates were first converted into lactate, and then lactate was metabolized into hydrogen with the co-production of butyrate. The hydrogen yield and the maximum volumetric hydrogen production rate achieved were 44.5 ± 2.9 NmL/g-CODfed and 1.9 NL/L-d, respectively. Further microbial community analysis revealed that Lactobacillus, Clostridium, and Klebsiella were the dominant bacterial genera when the hydrogen production rate peaked. It was therefore suggested that the metabolic potential behind the association between LAB and LO-HPB was important in driving the two-step lactate-type fermentation. Overall, the LD-DF can be a strategic hydrogen-producing pathway to be implemented with cheese whey. Full article
Show Figures

Figure 1

11 pages, 1583 KiB  
Article
Biogas Production and Energy Balance in a Two-Stage Anaerobic Digestion of Fruit and Vegetable Waste: Thermophilic versus Mesophilic
by Pham Van Dinh and Takeshi Fujiwara
Fermentation 2023, 9(7), 601; https://doi.org/10.3390/fermentation9070601 - 27 Jun 2023
Viewed by 1990
Abstract
This study aimed to investigate biogas production and energy balance in a two-stage anaerobic digestion system of fruit/vegetable waste under thermophilic and mesophilic conditions. Firstly, the feedstock was hydrolyzed and acidified in an acidic reactor at 37 °C with a retention time of [...] Read more.
This study aimed to investigate biogas production and energy balance in a two-stage anaerobic digestion system of fruit/vegetable waste under thermophilic and mesophilic conditions. Firstly, the feedstock was hydrolyzed and acidified in an acidic reactor at 37 °C with a retention time of 5 d. Then, the liquid hydrolysate was collected and pumped into an up-flow methane reactor under a mesophilic temperature with a retention time of 5 d and a thermophilic condition with a retention time of 3 d. The experimental results showed that in the thermophilic methane reactor, the COD removal, biogas yield, and methane concentration were 96.3%, 492 mL/g-VS, and 70.4%, respectively. These values were 3%, 10%, and 3% higher, respectively, than those obtained in the mesophilic methane reactor. In terms of energy, the mesophilic and thermophilic methane reactors consumed the same thermal energy demand for temperature control. They were much lower than the heat values produced by the power engine. The two-stage anaerobic digestion system using a thermophilic methane reactor obtained a gross energy of 11.20 kJ/g-VS and a net energy of 9.83 kJ/g-VS. These values were 13.2% and 14.8% higher, respectively, than those obtained by the system with a mesophilic condition. Moreover, the use of a thermophilic reactor helped reduce the reactor volume by 40%, leading to significant investment cost savings. Full article
Show Figures

Figure 1

13 pages, 933 KiB  
Article
Biogas Production from Steam-Exploded Maize Stover: Results from Continuous Anaerobic Tank Bioreactor Tests
by Abbas Shevidi, Javier Lizasoain, Bernhard Wlcek, Susanne Frühauf, Andreas Gronauer and Alexander Bauer
Fermentation 2023, 9(4), 339; https://doi.org/10.3390/fermentation9040339 - 28 Mar 2023
Cited by 2 | Viewed by 1235
Abstract
Steam explosion pretreatment of lignocellulosic biomass presents a promising technology for agricultural residues before anaerobic degradation. This study aimed to assess biogas production in continuously stirred tank reactors using steam-exploded maize stover mono-digestion. The continuous digestion tests were carried out in four fermenters [...] Read more.
Steam explosion pretreatment of lignocellulosic biomass presents a promising technology for agricultural residues before anaerobic degradation. This study aimed to assess biogas production in continuously stirred tank reactors using steam-exploded maize stover mono-digestion. The continuous digestion tests were carried out in four fermenters with a capacity of 150 L under mesophilic and thermophilic conditions. Maize stover was pretreated at 173 °C for 15 min. Four different organic loading rates (OLR) were tested, the biogas and methane production rate was monitored, and parameters such as dry matter (DM), volatile solids (VS), pH, and C:N were analyzed. The results of the tests showed that using steam-exploded maize stover in a continuous system over the range of an OLR from 1.0 to 3.5 kg VS m–3 d–1 is feasible with nitrogen as an additive only. The maximum methane yield, 637 LN m–3 d–1, was measured under thermophilic conditions with an OLR of 3.5 kg VS m–3 d–1. The trend of an increased gas production rate with an increasing OLR was observed over the range of the applied OLRs, although the average gas yield in the thermophilic mode was higher than it was in the mesophilic one. Full article
Show Figures

Figure 1

Back to TopTop