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Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives

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

Deadline for manuscript submissions: closed (15 September 2023) | Viewed by 18793

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Special Issue Editors

Dr. Miguel Ladero

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Guest Editor

Department of Chemical Engineering, College of Chemical Sciences, Complutense University of Madrid, 28040 Madrid, Spain
Interests: glycerol; biodiesel; valorization; catalysts; carbonates; ketals; monomers; ethers; esters; lactic acid; hydrogen; diols; refining; oxidation; dehydration; biorefinery; biomaterials
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Victoria E. Santos

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Guest Editor

Department of Chemical Engineering, College of Chemical Sciences, Complutense University of Madrid, 28040 Madrid, Spain
Interests: bioprocesses; gas-liquid transport; valorization; biorefineries; kinetic modelling; hydrodynamic and oxidative stress; ROS; platform biobased-chemicals

Special Issue Information

Dear Colleagues,

In a global situation marked by the need to find new material and energy resources, as well as novel processes and procedures that improve the efficiency of the use of any resource, plant biomass is shown to be an excellent set of raw materials for obtaining products that can compete with and ultimately replace chemical products from the petrochemical industry. The main characteristic of plant biomass is its renewability, in clear contrast to fossil sources. In fact, the capacity of terrestrial and marine plants to fix inorganic matter, including carbon dioxide, through photosynthesis, makes it possible to generate enormous quantities of matter, this so-called plant biomass.

The transformation of biomass into products of interest to mankind has gone from the typical processes of the food industry, the basis of first-generation refineries, to the transformation of lignocellulosic and similar materials from the structures of terrestrial and marine plants, including macroalgae. This biomass is the starting point of second and third generation biorefineries and is much more abundant than the food biomass of first generation biorefineries, while its use avoids stresses to the food and feed markets.

However, the structure of the biomass of plants and algae is refractory to transformation and requires numerous physical, chemical and biological or biocatalytic treatments to facilitate its transformation into platform chemicals or organic industrial intermediates to obtain the numerous chemical products demanded by our society.

This Special Issue is dedicated to the processes and operations that, with the help of enzymes, microorganisms and higher organisms, allow the access and transformation of biomass into chemical intermediates or platform chemicals.

Dr. Miguel Ladero
Prof. Dr. Victoria E. Santos
Guest Editors

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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

biorefinery
biotechnology
biocatalysis
accessibility
mass transport
reactivity
structure
valorization
platform chemical
bioreactor

Published Papers (13 papers)

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Editorial

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5 pages, 621 KiB

Open AccessEditorial

Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives

by Miguel Ladero Galán

Fermentation 2024, 10(1), 59; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation10010059 - 15 Jan 2024

Viewed by 991

Abstract

Over the past few decades, the need for new, more accessible and renewable raw materials has become evident [...] Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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Research

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15 pages, 5153 KiB

Open AccessArticle

Maximizing Bioethanol Production from Eucalyptus globulus Using Steam Explosion Pretreatment: A Multifactorial Design and Fermenter Development for High Solid Loads

by Eduardo Troncoso-Ortega, Roberto Valenzuela, Pablo Reyes-Contreras, Patricia Castaño-Rivera, L-Nicolás Schiappacasse and Carolina Parra

Fermentation 2023, 9(11), 965; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9110965 - 10 Nov 2023

Viewed by 1236

Abstract

Steam explosion pretreatment is suitable for bioethanol production from Eucalyptus globulus wood. Multifactorial experiment designs were used to find the optimal temperature and residence time required to obtain the best glucose yield from the enzymatic hydrolysis of pretreated materials. The chemical composition, crystallinity index, morphology and polymerization degree of the pretreated materials were correlated with enzymatic accessibility. Simultaneous saccharification and fermentation (SSF) using a fed-batch strategy was applied to three different laboratory-scale fermenters. The optimization of the pretreatment was obtained at 208 °C and 11 min. However, the enzymatic hydrolysis performance did not show significant differences from the material obtained at 196 °C and 9.5 min, which was determined to be the real optimum, owing to its lower energy requirement. The vertical fermenter with type “G” blades and the horizontal fermenter with helical blades were both highly efficient for reaching ethanol yields close to 90% based on dry wood, and ethanol concentrations close to 9.0% v/v. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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15 pages, 3239 KiB

Open AccessArticle

Microbial Fuel Cell Using a Novel Ionic Liquid-Type Membrane–Cathode Assembly for Animal Slurry Treatment and Fertilizer Production

by Eduardo Iniesta-López, Adrián Hernández-Fernández, Yolanda Garrido, Ioannis A. Ieropoulos and Francisco José Hernández-Fernández

Fermentation 2023, 9(9), 844; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9090844 - 14 Sep 2023

Viewed by 940

Abstract

The implementation of a microbial fuel cell for wastewater treatment and bioenergy production requires a cost reduction, especially when it comes to the ion exchange membrane part and the catalysts needed for this purpose. Ionic liquids in their immobilized phase in proton exchange membranes and non-noble catalysts, as alternatives to conventional systems, have been intensively investigated in recent years. In the present study, a new microbial fuel cell technology, based on an ionic liquid membrane assembly for CoCu mixed oxide catalysts, is proposed to treat animal slurry. The new low-cost membrane–cathode system is prepared in one single step, thus simplifying the manufacturing process of a membrane–cathode system. The novel MFCs based on the new low-cost membrane–cathode system achieved up to 51% of the power reached when platinum was used as a catalyst. Furthermore, the removal of organic matter in suspension after 12 days was higher than that achieved with a conventional system based on the use of platinum catalysts. Moreover, struvite, a precipitate consisting of ammonium, magnesium, and phosphate, which could be used as a fertilizer, was recovered using this membrane–cathode system. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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16 pages, 1056 KiB

Open AccessEditor’s ChoiceArticle

Lactic Acid Production from Steam-Exploded Sugarcane Bagasse Using Bacillus coagulans DSM2314

by William Rodrigues Alves, Thiago Alessandre da Silva, Arion Zandoná Filho and Luiz Pereira Ramos

Fermentation 2023, 9(9), 789; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9090789 - 26 Aug 2023

Cited by 1 | Viewed by 1417

Abstract

This work aimed at producing lactic acid (LA) from sugarcane bagasse after steam explosion at 195 °C for 7.5 and 15 min. Enzymatic hydrolysis was carried out with Cellic CTec3 and Cellic HTec3 (Novozymes), whereas fermentation was performed with Bacillus coagulans DSM2314. Water washing of pretreated solids before enzymatic hydrolysis improved both hydrolysis and fermentation yields. The presence of xylo-oligosaccharides (XOS) in substrate hydrolysates reduced hydrolysis efficiency, but their effect on fermentation was negligible. The presence of fermentation inhibitors in C5 streams was circumvented by adsorption on activated carbon powder with no detectable sugar losses. High carbohydrates-to-LA conversions (Y_p/s) of 0.88 g·g⁻¹ were obtained from enzymatic hydrolysates of water-washed steam-exploded materials that were produced at 195 °C, in 7.5 min, and the use of centrifuged-but-never-washed pretreated solids decreased Y_p/s by 16%. However, when the detoxified C5 stream was added at a 10% ratio, Y_p/s was raised to 0.93 g·g⁻¹ for an LA productivity of 2.55 g·L⁻¹·h⁻¹. Doubling the pretreatment time caused a decrease in Y_p/s to 0.78 g·g⁻¹, but LA productivity was the highest (3.20 g·L⁻¹·h⁻¹). For pretreatment at 195 °C for 7.5 min, the elimination of water washing seemed feasible, but the use of longer pretreatment times made it mandatory to eliminate fermentation inhibitors. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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18 pages, 1855 KiB

Open AccessArticle

Study on the Operational Modes Using Both Growing and Resting Cells for Succinic Acid Production from Xylose Kinetic Modelling

by Itziar A. Escanciano, Vanessa Ripoll, Miguel Ladero and Victoria E. Santos

Fermentation 2023, 9(7), 663; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9070663 - 14 Jul 2023

Cited by 3 | Viewed by 905

Abstract

Succinic acid (SA) is one of the most prominent C4 biomass-based platform chemicals that can be biologically obtained. This article verifies, for the first time, the possibility of producing succinic acid with fed-batch or repeated batch operations with Actinobacillus succinogenes in a resting state, that is, in the absence of a nitrogen source. In this work it is possible to optimise separately the stages of cell growth and production in the fed-batch or repeated batch modes, minimising the costs associated with the nitrogen source and facilitating the subsequent purification of SA. These experiments were carried out with xylose, the most abundant monosaccharide in hemicelluloses, with the results subsequently being compared to those obtained in equivalent operations carried out with cells in a state of growth. First, a cost-effective synthetic growth medium was proposed and successfully employed for SA production. Biocatalysts’ reutilisation showed that the bioprocess can be carried out successfully in repeated batch and fed-batch modes. The best mode for growing cells is repeated batch, achieving a maximum productivity of 0.77 g‧L⁻¹‧h⁻¹, a selectivity of 53% and a yield of 51% with respect to xylose consumed. In contrast, the fed-batch mode was found to be the most convenient mode with resting cell biocatalyst, reaching a maximum productivity of 0.83 g‧L⁻¹‧h⁻¹, a selectivity of 0.78 g‧g⁻¹ and a yield of 68% with respect to the xylose consumed. In addition, by-product formation is significantly reduced when employing resting cells. An unstructured non-segregated kinetic model was developed for both biocatalysts, capable of simulating cell growth, xylose consumption, SA production and by-product generation, with successful estimation of kinetic parameters supported by statistical criteria. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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17 pages, 3639 KiB

Open AccessEditor’s ChoiceArticle

Lactic Acid Production from Cow Manure: Experimental Process Conditions Analysis

by Ricard Garrido, Víctor Falguera, Omar Pérez Navarro, Amanda Acosta Solares and Luisa F. Cabeza

Fermentation 2023, 9(7), 604; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9070604 - 27 Jun 2023

Cited by 1 | Viewed by 1665

Abstract

The production of cow manure far exceeds the quantity that can be utilized in primary applications such as fertilizer or for the generation of biogas. As a result, alternative value-added applications are being investigated. The purpose of this study is to evaluate the production of lactic acid, using cow manure as the raw material. The methodology involved the implementation of thermochemical pretreatment for the cow manure, followed by simultaneous saccharification and fermentation for lactic acid production. Response surface methodology based on a central composite design was employed to analyze the simultaneous saccharification and fermentation process. The factorial design of the experiments was carried out with three factors, cow manure concentration, temperature, and enzyme concentration, with 80 g·L⁻¹, 50 °C, and 212.5 IU/gCM_{Dry Matter} as central point values, respectively. Following the addition of Bacillus coagulans DSM2314 inoculum to enzymatically hydrolyzed cow manure at pH 5.0, after a 24 h period the concentration of lactic acid was recorded at 13.65 g·L⁻¹, with a conversion efficiency of 33.1%. Studies were conducted until 48 h to analyze time impact. Characterization studies for native cow manure and that pretreated using acid reagent were conducted. Sugar content and by-product formation were analyzed, resulting in 23.24 g·L⁻¹ of sugar remaining as the maximum after fermentation, while low values of furfural (1.04 g·L⁻¹), 5-hydroxymethylfurfural (1.35 g·L⁻¹), and acetic acid (1.45 g·L⁻¹) were found. Optimal conditions were calculated at 24 and 48 h with R software, obtaining the lactic acid, with yields of 13.4 g·L⁻¹, 36.28% (for 24 h) and 15.27 g·L⁻¹, 32.76% (for 48 h), respectively. Experimental and statistical studies of enzymatic hydrolysis and fermentation stated that cow manure was a feasible substrate for the production of lactic acid. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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15 pages, 1550 KiB

Open AccessArticle

Biotechnological Production of Fumaric Acid by Rhizopus arrhizus—Reaching Industrially Relevant Final Titers

by Anja Kuenz, Laslo Eidt and Ulf Prüße

Fermentation 2023, 9(7), 588; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9070588 - 23 Jun 2023

Viewed by 1046

Abstract

Fumaric acid is used in various areas of the chemical industry due to its functional groups. For example, it is used in the polymer industry to produce unsaturated polyester resins, which are nowadays mostly produced from fossil raw materials. With regard to sustainable biotechnological fumaric acid production, the main challenge is to develop a cost-effective and robust fermentation process with industrially relevant final titers, productivities and yields. For biotechnological fumaric acid production, mainly fungi of the genus Rhizopus are used, which require very complex and challenging morphology control. The aim of this work is the development of an effective biotechnological fumaric acid production process with R. arrhizus NRRL 1526. Significant insights into the morphology control of the fungus and optimization of production characteristics were obtained, and a final titer of 86.3 g/L fumaric acid was achieved in a batch cultivation, with a yield of 0.67 g/g and a productivity of 0.60 g/(L∙h). In addition, a fed-batch process was developed, in which the production phase was extended, and a maximum final titer of 195.4 g/L fumaric acid was achieved. According to current knowledge, this value is the highest final concentration of fumaric acid produced using biotechnology. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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13 pages, 4000 KiB

Open AccessArticle

Heterologous Expression and Biochemical Characterization of a Thermostable Endoglucanase (MtEG5-1) from Myceliophthora thermophila

by Wenyuan Zhou, Sheng Tong, Farrukh Raza Amin, Wuxi Chen, Jinling Cai and Demao Li

Fermentation 2023, 9(5), 462; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9050462 - 12 May 2023

Cited by 1 | Viewed by 1515

Abstract

Thermophilic endoglucanases have become of significant interest for effectively catalyzing the hydrolysis of cellulose. Myceliophthora thermophila is an ideal source of thermophilic enzymes. Interestingly, different hosts differently express the same enzymes. In this study, we successfully overexpressed endoglucanase (MtEG5-1) from M. thermophila in the methylotrophic yeast, Pichia pastoris GS115, via electroporation. We found that purified MtEG5-1 exhibited optimum activity levels at pH 5 and 70 °C, with 88% thermal stability after being incubated at 70 °C for 2 h. However, we observed that purified MtEG5-1 had a molecular weight of 55 kDa. The Km and Vmax values of purified MtEG5-1 were approximately 6.11 mg/mL and 91.74 μmol/min/mg at 70 °C (pH 5.0), respectively. Additionally, the optimum NaCl concentration of purified MtEG5-1 was found to be 6 g/L. Furthermore, we observed that the activity of purified MtEG5-1 was significantly enhanced by Mn²⁺ and was inhibited by K⁺. These results indicated that MtEG5-1 expressed by P. pastoris GS115 is more heat-tolerant than that expressed by A. niger and P. pastoris X33. These properties of MtEG5-1 make it highly suitable for future academic research and industrial applications. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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21 pages, 4274 KiB

Open AccessArticle

Multi-Response Optimization of Thermochemical Pretreatment of Soybean Hulls for 2G-Bioethanol Production

by Martín Gil Rolón, Rodrigo J. Leonardi, Bruna C. Bolzico, Lisandro G. Seluy, Maria T. Benzzo and Raúl N. Comelli

Fermentation 2023, 9(5), 454; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9050454 - 10 May 2023

Viewed by 1357

Abstract

Soybean is a major crop used in the production of human food. The soybean hull (SH) is also known as the seed coat and it constitutes about 5–8% of the total seed on a dry weight basis, depending on the variety and the seed size. Dilute sulfuric acid was employed for the thermochemical pretreatment of SH prior to enzymatic saccharification and alcoholic fermentation. Empirical modeling of response surface, severity factor and multi-response desirability function methodology, were used to perform the process optimization. Temperature, acid concentration and reaction time were defined as operational variables, while furfural, 5-hydroxymethylfurfural and solubilized hemicellulose and cellulose were defined as response variables. Mathematical models satisfactorily described the process and optimal conditions were found at 121 °C; 2.5% w/v H₂SO₄ and 60 min. More than 80% and 90% of hemicelluloses and celluloses, respectively, were able to solubilize at this point. The fermentation performance of an industrial Saccharomyces cerevisiae strain was also evaluated. The glucose available in the hydrolysates was completely consumed in less than 12 h, with an average ethanol yield of 0.45 g_ethanol/g_glucose. Thus, the thermochemical conditioning of SH with dilute sulfuric acid is a suitable operation for 2G-bioethanol production. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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18 pages, 3761 KiB

Open AccessArticle

The TgRas1 Gene Affects the Lactose Metabolism of Trichoderma guizhouense NJAU4742

by Jiaxi Miao, Chen Chen, Yajing Gu, Han Zhu, Haiyang Guo, Dongyang Liu and Qirong Shen

Fermentation 2023, 9(5), 440; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9050440 - 04 May 2023

Viewed by 1253

Abstract

Trichoderma is one of the fungi commonly used in fermentation engineering. The hydrolytic enzymes secreted by Trichoderma have great economic value. Trichoderma guizhouense NJAU4742 is a branch of Trichoderma harzianum, which also has application potential. Lactose can induce fungi to secrete cellulase. Unfortunately, neither the lactose-inducing effect nor the mechanism of lactose metabolism in the study of Trichoderma guizhouense NJAU4742 is clear. Our study showed that carbon sources such as glucose, galactose, and sucrose could not induce cellulase secretion from Trichoderma guizhouense NJAU4742. Lactose induced the filter paper activity of the cellulase secreted by Trichoderma to reach 4.13 ± 0.11 U·mL⁻¹. The ratio of 0.4% lactose–0.6% straw is the best way to induce cellulase and is better than adding only straw or lactose. TgRas family genes respond differently to different carbon sources at the gene level, and these proteins may be involved in different carbon source metabolisms. The results of transcriptional responses under different growth conditions showed that TgRas1 occupies a dominant position among TgRas family genes. The growth of the ΔTgRas1 mutant on the plate was inhibited, and the hyphae were dense, thick, and swollen. Under the condition of lactose, the biomass of ΔTgRas1 was severely inhibited in liquid fermentation, and its biomass decreased by 91.43% compared with WT. The liquid fermentation of ΔTgRas1 under other carbon source conditions was not affected. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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14 pages, 1124 KiB

Open AccessArticle

Continuous Bioproduction of Alginate Bacterial under Nitrogen Fixation and Nonfixation Conditions

by Pablo Contreras-Abara, Tania Castillo, Belén Ponce, Viviana Urtuvia, Carlos Peña and Alvaro Díaz-Barrera

Fermentation 2023, 9(5), 426; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9050426 - 28 Apr 2023

Cited by 1 | Viewed by 1473

Abstract

Alginate is a biomaterial produced by Azotobacter vinelandii, a diazotroph that, under nitrogen-fixing conditions, can fix nitrogen under high oxygen levels. In A. vinelandii, alginate is synthesized from fructose-6P via synthesis of precursor, polymerization, and modification/exportation. Due to its viscosifying, gelling, and thickening characteristics, alginate is widely used in food, pharmaceutical, and cosmetical industries. This study aimed to develop a continuous bioprocess and a comparative analysis of alginate production under diazotrophic and nondiazotrophic conditions. Continuous cultures were developed at three dilution rates (0.06, 0.08 and 0.10 h⁻¹). In steady state, the respiratory activity, alginate production, alginate molecular weight and the genes encoding alginate polymerase were determined. Under the conditions studied, the specific oxygen uptake rate and respiratory quotient were similar. The diazotrophic conditions improved the conversion of sucrose to alginate and the specific productivity rate, which was 0.24 ± 0.03 g g⁻¹ h⁻¹. A higher alginate molecular weight (725 ± 20 kDa) was also achieved under diazotrophic conditions, which can be explained by an increase in the gene expression of genes alg8 and alg44 (encoding polymerase). The results of this work show the feasibility of enhancing alginate production (yields and specific productivity rates) and quality (molecular weight) under nitrogen-fixing conditions, opening the possibility of developing a continuous bioprocess to produce alginate with specific characteristics under conditions of diazotrophy. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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17 pages, 1757 KiB

Open AccessArticle

Development of a Simple and Robust Kinetic Model for the Production of Succinic Acid from Glucose Depending on Different Operating Conditions

by Itziar A. Escanciano, Miguel Ladero, Victoria E. Santos and Ángeles Blanco

Fermentation 2023, 9(3), 222; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9030222 - 25 Feb 2023

Cited by 4 | Viewed by 1829

Abstract

Succinic acid (SA) is one of the main identified biomass-derived chemical building blocks. In this work we approach the study of its production by Actinobacillus succinogenes DSM 22257 from glucose, focusing on the development and application of a simple kinetic model capable of representing the evolution of the process over time for a great diversity of process variables key to the production of this platform bio-based chemical: initial biomass concentration, yeast extract concentration, agitation speed, and carbon dioxide flow rate. All these variables were studied experimentally, determining the values of key fermentation parameters: titer (23.8–39.7 g·L⁻¹), yield (0.59–0.72 g_SA·g_glu⁻¹), productivity (0.48–0.96 g_SA·L⁻¹·h⁻¹), and selectivity (0.61–0.69 g_SA·g_glu⁻¹). Even with this wide diversity of operational conditions, a non-structured and non-segregated kinetic model was suitable for fitting to experimental data with high accuracy, considering the values of the goodness-of-fit statistical parameters. This model is based on the logistic equation for biomass growth and on potential kinetic equations to describe the evolution of SA and the sum of by-products as production events that are not associated with biomass growth. The application of the kinetic model to diverse operational conditions sheds light on their effect on SA production. It seems that nitrogen stress is a good condition for SA titer and selectivity, there is an optimal inoculum mass for this purpose, and hydrodynamic stress starts at 300 r.p.m. in the experimental set-up employed. Due to its practical importance, and to validate the developed kinetic model, a fed-batch fermentation was also carried out, verifying the goodness of the model proposed via the process simulation (stage or cycle 1) and application to further cycles of the fed-batch operation. The results showed that biomass inactivation started at cycle 3 after a grace period in cycle 2. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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Review

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20 pages, 3763 KiB

Open AccessReview

Sugar Beet Pulp as Raw Material for the Production of Bioplastics

by Cristina Marzo-Gago, Ana Belén Díaz and Ana Blandino

Fermentation 2023, 9(7), 655; https://0-doi-org.brum.beds.ac.uk/10.3390/fermentation9070655 - 12 Jul 2023

Cited by 1 | Viewed by 2207

Abstract

The production of bioplastics from renewable materials has gained interest in recent years, due to the large accumulation of non-degradable plastic produced in the environment. Here, sugar beet pulp (SBP) is evaluated as a potential raw material for the production of bioplastics such as polylactic acid (PLA) and polyhydroxyalkanoates (PHAs). SBP is a by-product obtained in the sugar industry after sugar extraction from sugar beet, and it is mainly used for animal feed. It has a varied composition consisting mainly of cellulose, hemicellulose and pectin. Thus, it has been used to produce different value-added products such as methane, hydrogen, pectin, simple sugars, ethanol, lactic acid and succinic acid. This review focuses on the different bioprocesses involved in the production of lactic acid and PHAs, both precursors of bioplastics, from sugars derived from SBP. The review, therefore, describes the pretreatments applied to SBP, the conditions most frequently used for the enzymatic hydrolysis of SBP as well as the fermentation processes to obtain LA and PHAs. Full article

(This article belongs to the Special Issue Upstream Bioprocesses to Biomass-Based Platform Chemicals and Derivatives)

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