Integrated Consolidated Bioprocessing for Conversion of Lignocellulosic Feedstock to Biofuels and Value-Added Bioproducts

A biorefinery integrated process based on lignocellulosic feedstock is especially interesting in rural areas with a high density of agricultural and agro-industrial wastes, which is the case for olive crop areas and their associated industries. In the region of Andalusia, in the south of Spain, the provinces of Jaén, Córdoba and Seville accumulate more than 70% of the olive wastes generated in Spain. Therefore, the valorisation of these wastes is a matter of interest from both an environmental and a social point of view. The olive biorefinery involves a multi-product process from different raw materials: olive leaves, exhausted olive pomace, olive stones and olive tree pruning residues. Biorefinery processes associated with these wastes would allow their valorisation to produce bioenergy and high value-added renewable products. In this work, using geographic information system tools, the biomass from olive crop fields, mills and olive pomace-extracting industries, where these wastes are generated, was determined and quantified in the study area. In addition, the vulnerability of the territory was evaluated through an environmental and territorial analysis that allowed for the determination of the reception capacity of the study area. Then, information layers corresponding to the availability of the four biomass wastes, and layers corresponding to the environmental fragility of the study area were overlapped and they resulted in an overall map. This made it possible to identify the best areas for the implementation of the biorefineries based on olive-derived biomass. Finally, as an example, three zones were selected for this purpose. These locations corresponded to low fragility areas with a high availability of biomass (more than 300,000 tons/year) in a 30 km radius, which would ensure the biomass supply.

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Consolidated bioprocessing of lignocellulose for production of glucaric acid by an artificial microbial consortium

Biotechnology for Biofuels ◽

10.1186/s13068-021-01961-7 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Chaofeng Li ◽

Xiaofeng Lin ◽

Xing Ling ◽

Shuo Li ◽

Hao Fang

Keyword(s):

Acid Production ◽

Microbial Consortium ◽

Consolidated Bioprocessing ◽

High Titer ◽

Value Added ◽

Superior Performance ◽

Glucaric Acid ◽

Practical Applications ◽

Work Distribution ◽

Rut C30

Abstract Background The biomanufacturing of d-glucaric acid has attracted increasing interest because it is one of the top value-added chemicals produced from biomass. Saccharomyces cerevisiae is regarded as an excellent host for d-glucaric acid production. Results The opi1 gene was knocked out because of its negative regulation on myo-inositol synthesis, which is the limiting step of d-glucaric acid production by S. cerevisiae. We then constructed the biosynthesis pathway of d-glucaric acid in S. cerevisiae INVSc1 opi1Δ and obtained two engineered strains, LGA-1 and LGA-C, producing record-breaking titers of d-glucaric acid: 9.53 ± 0.46 g/L and 11.21 ± 0.63 g/L d-glucaric acid from 30 g/L glucose and 10.8 g/L myo-inositol in fed-batch fermentation mode, respectively. However, LGA-1 was preferable because of its genetic stability and its superior performance in practical applications. There have been no reports on d-glucaric acid production from lignocellulose. Therefore, the biorefinery processes, including separated hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF) and consolidated bioprocessing (CBP) were investigated and compared. CBP using an artificial microbial consortium composed of Trichoderma reesei (T. reesei) Rut-C30 and S. cerevisiae LGA-1 was found to have relatively high d-glucaric acid titers and yields after 7 d of fermentation, 0.54 ± 0.12 g/L d-glucaric acid from 15 g/L Avicel and 0.45 ± 0.06 g/L d-glucaric acid from 15 g/L steam-exploded corn stover (SECS), respectively. In an attempt to design the microbial consortium for more efficient CBP, the team consisting of T. reesei Rut-C30 and S. cerevisiae LGA-1 was found to be the best, with excellent work distribution and collaboration. Conclusions Two engineered S. cerevisiae strains, LGA-1 and LGA-C, with high titers of d-glucaric acid were obtained. This indicated that S. cerevisiae INVSc1 is an excellent host for d-glucaric acid production. Lignocellulose is a preferable substrate over myo-inositol. SHF, SSF, and CBP were studied, and CBP using an artificial microbial consortium of T. reesei Rut-C30 and S. cerevisiae LGA-1 was found to be promising because of its relatively high titer and yield. T. reesei Rut-C30 and S. cerevisiae LGA-1were proven to be the best teammates for CBP. Further work should be done to improve the efficiency of this microbial consortium for d-glucaric acid production from lignocellulose.

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Hydrolytic secretome engineering in Yarrowia lipolytica for consolidated bioprocessing on polysaccharide resources: review on starch, cellulose, xylan, and inulin

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11097-1 ◽

2021 ◽

Vol 105 (3) ◽

pp. 975-989

Author(s):

Ewelina Celińska ◽

Jean-Marc Nicaud ◽

Wojciech Białas

Keyword(s):

Yarrowia Lipolytica ◽

High Efficiency ◽

Consolidated Bioprocessing ◽

Genome Mining ◽

Value Added ◽

Process Models ◽

Process Efficiency ◽

Secretory Proteins ◽

Microbial Conversion ◽

Key Points

Abstract Consolidated bioprocessing (CBP) featuring concomitant hydrolysis of renewable substrates and microbial conversion into value-added biomolecules is considered to bring substantial benefits to the overall process efficiency. The biggest challenge in developing an economically feasible CBP process is identification of bifunctional biocatalyst merging the ability to utilize the substrate and convert it to value-added product with high efficiency. Yarrowia lipolytica is known for its exceptional performance in hydrophobic substrates assimilation and storage. On the other hand, its capacity to grow on plant-derived biomass is strongly limited. Still, its high potential to simultaneously overproduce several secretory proteins makes Y. lipolytica a platform of choice for expanding its substrate range to complex polysaccharides by engineering its hydrolytic secretome. This review provides an overview of different genetic engineering strategies advancing development of Y. lipolytica strains able to grow on the following four complex polysaccharides: starch, cellulose, xylan, and inulin. Much attention has been paid to genome mining studies uncovering native potential of this species to assimilate untypical sugars, as in many cases it turns out that dormant pathways are present in Y. lipolytica’s genome. In addition, the magnitude of the economic gain by CBP processing is here discussed and supported with adequate calculations based on simulated process models. Key points • The mini-review updates the knowledge on polysaccharide-utilizing Yarrowia lipolytica. • Insight into molecular bases founding new biochemical qualities is provided. • Model industrial processes were simulated and the associated costs were calculated.

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Basic Steps to Promote Biorefinery Value Chains in Forestry in Italy

Sustainability ◽

10.3390/su132111731 ◽

2021 ◽

Vol 13 (21) ◽

pp. 11731

Author(s):

Swati Tamantini ◽

Alberto Del Lungo ◽

Manuela Romagnoli ◽

Alessandro Paletto ◽

Michael Keller ◽

...

Keyword(s):

Value Added ◽

Energy Generation ◽

Value Chains ◽

Wood Biomass ◽

Wood Industry ◽

Lignocellulosic Feedstock ◽

New Methodologies ◽

End Use ◽

Main Components ◽

Value Added Products

Biorefineries are an important pillar to conduct the transition toward a circular bioeconomy. Forestry value chains produce wood biomass from harvesting and processing residues that have potential to be used in biorefineries, but currently, these residues are mostly used for energy generation. New biorefineries and new methodologies of wood fractionation allow the production of high value-added products based on carbohydrates and lignin. However, biorefineries based on lignocellulosic feedstock are still few in European countries and even less in Italy. The present study analyses the processes involved in a scenario of establishment of forest biorefineries, reviewing the main components and the actual organization of forestry value chains in Italy. The aim is to have a general vision, to identify and to focus the possibilities of the actual value chains and to fill gaps. The development of the territories is thought of in a perspective of a broader repertoire and more branched value chains than simple energy-generation end use, reviewing the tool for a feasibility study that could potentially involve lignocellulosic biorefineries also based on forest-wood industry feedstocks.

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Consolidated bioprocessing of lignocellulose for production of glucaric acid by an artificial microbial consortium

10.21203/rs.3.rs-29885/v2 ◽

2021 ◽

Author(s):

Chaofeng Li ◽

Xiaofeng Lin ◽

Xing Ling ◽

Shuo Li ◽

Hao Fang

Keyword(s):

Acid Production ◽

Microbial Consortium ◽

Consolidated Bioprocessing ◽

High Titer ◽

Value Added ◽

Glucaric Acid ◽

Work Distribution ◽

Fed Batch Fermentation ◽

Excellent Work ◽

Rut C30

Abstract Background: The biomanufacturing of D-glucaric acid has been attracted increasing interest because it is one of the top value-added chemicals produced from biomass. Saccharomyces cerevisiae is regarded as an excellent host for D-glucaric acid production. Results: The opi1 gene was knocked out because of its negative regulation on myo-inositol synthesis, which is the limiting step of D-glucaric acid production by S. cerevisiae. Then we constructed the biosynthetic pathway of D-glucaric acid in S. cerevisiae INVSc1 opi1Δ and obtained two engineered strains, LGA-1 and LGA-C, producing record breaking titers of D-glucaric acid, 9.53 ± 0.46 g/L and 11.21 ± 0.63 g/L D-glucaric acid from 30 g/L glucose and 10.8 g/L myo-inositol in the mode of fed-batch fermentation, respectively. However, LGA-1 was more preferable because of the genetic stability and the outperformance in applications. So far, there have been no reports on D-glucaric acid production from lignocellulose. Therefore, the biorefinery processes including separated hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF) and consolidated bioprocessing (CBP) were investigated and compared. CBP by an artificial microbial consortium composed of Trichoderma reesei Rut-C30 and S. cerevisiae LGA-1 was found to have relatively high D-glucaric acid titers and yields after 7 d fermentation, 0.54 ± 0.12 g/L D-glucaric acid from 15 g/L Avicel, and 0.45 ± 0.06 g/L D-glucaric acid from 15 g/L steam exploded corn stover (SECS), respectively. In attempts to design the microbial consortium for more efficient CBP the team consisted of the two members, T. reesei Rut-C30 and S. cerevisiae LGA-1, was found to be the best with excellent work distribution and collaboration.Conclusions: Two engineered S. cerevisiae strains, LGA-1 and LGA-C, with high titers of D-glucaric acid were obtained. This indicates that S. cerevisiae INVSc1 was an excellent host. Lignocellulose is a more preferable substrate than myo-inositol. SHF, SSF and CBP were studied and CBP by an artificial microbial consortium of T. reesei Rut-C30 and S. cerevisiae LGA-1 was found to be promising because of the relatively high titer and yield. T. reesei Rut-C30 and S. cerevisiae LGA-1were proved to be the best teammates for CBP. Further work should be done to improve the efficiency of this microbial consortium for D-glucaric acid production from lignocellulose.

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Recent Advances in Applications of Acidophilic Fungal Microbes for Bio-Chemicals

10.20944/preprints201804.0204.v1 ◽

2018 ◽

Author(s):

Rehman Javaid ◽

Aqsa Sabir ◽

Nadeem Sheikh ◽

Muhammad Ferhan

Keyword(s):

Acetic Acid ◽

Aromatic Compounds ◽

Value Added ◽

Enzymatic Conversion ◽

Environment Friendly ◽

Lignocellulosic Feedstock ◽

Phenyl Propanoid ◽

Inorganic As ◽

Lignin Peroxidases ◽

Lignin Depolymerization

Lignocellulosic feedstock (cellulose, hemicellulose and lignin) has been used for a variety of purposes. Among them, lignin can produce value-added chemicals having phenyl-propanoid subunits known as core lignin, possessing either C-C bonds or ether linkages. It can be depolymerized by microbial activity together with certain enzymes (laccases and peroxidases). Both acetic acid and formic acid production by certain fungi contribute significantly to lignin depolymerization. Natural organic acids production by fungi has many key roles in nature that are strictly dependent upon organic acid producing fungus type. Enzymatic conversion of lignocellulosic is beneficial over other physiochemical processes. Laccases, the copper containing proteins oxidize a broad spectrum of inorganic as well as organic compounds but most specifically phenolic compounds by radical catalyzed mechanism. Similarly, lignin peroxidases (LiP), the heme containing proteins perform a vital part in oxidizing a wide variety of aromatic compounds with H2O2. Lignin depolymerization yields polyaromatics, the important ones are BTX (Benzene, Xylene and Toluene), found in several different configurations. However, most modern aromatics complexes enhance the production of p-xylene, benzene and sometimes o-xylene respectively. Thus, this review will provide a concept that chemical and biological modifications of lignin yield certain value added and environment friendly chemicals.

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Novel Yeast Strains for the Efficient Saccharification and Fermentation of Starchy By-Products to Bioethanol

Energies ◽

10.3390/en12040714 ◽

2019 ◽

Vol 12 (4) ◽

pp. 714 ◽

Cited By ~ 12

Author(s):

Nicoletta Gronchi ◽

Lorenzo Favaro ◽

Lorenzo Cagnin ◽

Silvia Brojanigo ◽

Valentino Pizzocchero ◽

...

Keyword(s):

Process Integration ◽

Consolidated Bioprocessing ◽

Scale Up ◽

Cost Savings ◽

Value Added ◽

Yeast Strains ◽

Technological Advances ◽

Set Up ◽

Simultaneous Saccharification ◽

Selection Of

The use of solid starchy waste streams to produce value-added products, such as fuel ethanol, is a priority for the global bio-based economy. Despite technological advances, bioethanol production from starch is still not economically competitive. Large cost-savings can be achieved through process integration (consolidated bioprocessing, CBP) and new amylolytic microbes that are able to directly convert starchy biomass into fuel in a single bioreactor. Firstly, CBP technology requires efficient fermenting yeast strains to be engineered for amylase(s) production. This study addressed the selection of superior yeast strains with high fermentative performances to be used as recipient for future CBP engineering of fungal amylases. Twenty-one newly isolated wild-type Saccharomyces cerevisiae strains were screened at 30 °C in a simultaneous saccharification and fermentation (SSF) set up using starchy substrates at high loading (20% w/v) and the commercial amylases cocktail STARGEN™ 002. The industrial yeast Ethanol Red™ was used as benchmark. A cluster of strains produced ethanol levels (up to 118 g/L) significantly higher than those of Ethanol Red™ (about 109 g/L). In particular, S. cerevisiae L20, selected for a scale-up process into a 1-L bioreactor, confirmed the outstanding performance over the industrial benchmark, producing nearly 101 g/L ethanol instead of 94 g/L. As a result, this strain can be a promising CBP host for heterologous expression of fungal amylases towards the design of novel and efficient starch-to-ethanol routes.

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Od rastlinske biomase do biogoriv in bio-surovin z mikrobnimi celičnimi tovarnami

Acta agriculturae Slovenica ◽

10.14720/aas.2020.116.1.1331 ◽

2020 ◽

Vol 116 (1) ◽

pp. 75

Author(s):

Maša VODOVNIK ◽

Matevž ZLATNAR

Keyword(s):

Renewable Energy ◽

Plant Biomass ◽

Consolidated Bioprocessing ◽

Raw Materials ◽

Value Added ◽

Cost Effective ◽

Human Society ◽

Microbial Cell Factories ◽

Cell Factories ◽

Wide Range

<p>Global energy demands and global warming represent key challenges of the future of human society. Continous renewable energy supply is key for sustainable economy development. Waste plant biomass represent abundant source of renewable energy that can be transformed to biofuels and other value-added products, which is currently limited due to the lack of cost-effective biocatalysts. The bottleneck of this process is the degradation of structural polysaccharides of plant cell walls to soluble compounds that can be fermented to solvents or transformed to biogas via methanogenesis and can be used as biofuels or chemical raw materials. In order to replace traditional physical and chemical methods of lignocellulose pretreatment with more environmentally friendly biological approaches, native microbial enzyme systems are increasingly being explored as potential biocatalysts that could be used in these processes. Microbial enzymes are useful either as catalysts in the enzymatic hydrolysis of lignocelluloses or as components incorporated in engineered microbes for consolidated bioprocessing of lignocelluloses. The unprecedented development of tools for genetic and metabolic engineering for a wide range of microorganisms enabled significant progress in the development of microbial cell factories optimized for the producton of biofuels. One of the most promising strategies aimed towards this goal, i.e. systematic design and heterologous expression of »designer cellulosomes« in industrial solventogenic strains is adressed in detail.</p>

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Coordination of consolidated bioprocessing technology and carbon dioxide fixation to produce malic acid directly from plant biomass in Myceliophthora thermophila

Biotechnology for Biofuels ◽

10.1186/s13068-021-02042-5 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Jingen Li ◽

Bingchen Chen ◽

Shuying Gu ◽

Zhen Zhao ◽

Qian Liu ◽

...

Keyword(s):

Malic Acid ◽

Plant Biomass ◽

Consolidated Bioprocessing ◽

Average Rate ◽

Value Added ◽

Cost Effective ◽

Myceliophthora Thermophila ◽

Carbon Efficiency ◽

Bulk Chemicals ◽

Promising Strategy

Abstract Background Consolidated bioprocessing (CBP) technique is a promising strategy for biorefinery construction, producing bulk chemicals directly from plant biomass without extra hydrolysis steps. Fixing and channeling CO2 into carbon metabolism for increased carbon efficiency in producing value-added compounds is another strategy for cost-effective bio-manufacturing. It has not been reported whether these two strategies can be combined in one microbial platform. Results In this study, using the cellulolytic thermophilic fungus Myceliophthora thermophila, we designed and constructed a novel biorefinery system DMCC (Direct microbial conversion of biomass with CO2 fixation) through incorporating two CO2 fixation modules, PYC module and Calvin–Benson–Bassham (CBB) pathway. Harboring the both modules, the average rate of fixing and channeling 13CO2 into malic acid in strain CP51 achieved 44.4, 90.7, and 80.7 mg/L/h, on xylose, glucose, and cellulose, respectively. The corresponding titers of malic acid were up to 42.1, 70.4, and 70.1 g/L, respectively, representing the increases of 40%, 10%, and 7%, respectively, compared to the parental strain possessing only PYC module. The DMCC system was further improved by enhancing the pentose uptake ability. Using raw plant biomass as the feedstock, yield of malic acid produced by the DMCC system was up to 0.53 g/g, with 13C content of 0.44 mol/mol malic acid, suggesting DMCC system can produce 1 t of malic acid from 1.89 t of biomass and fix 0.14 t CO2 accordingly. Conclusions This study designed and constructed a novel biorefinery system named DMCC, which can convert raw plant biomass and CO2 into organic acid efficiently, presenting a promising strategy for cost-effective production of value-added compounds in biorefinery. The DMCC system is one of great options for realization of carbon neutral economy.

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Sustainable 2,5-furandicarboxylic synthesis by a direct 5-hydroxymethylfurfural fuel cell based on a bifunctional PtNiSx catalyst

Chemical Communications ◽

10.1039/d0cc06087a ◽

2020 ◽

Vol 56 (88) ◽

pp. 13611-13614

Author(s):

Jialu Wang ◽

Xian Zhang ◽

Guozhong Wang ◽

Yunxia Zhang ◽

Haimin Zhang

Keyword(s):

Fuel Cell ◽

Electric Energy ◽

Value Added ◽

Chemical Energy ◽

New Type

A new type of direct 5-hydroxymethylfurfural (HMF) oxidation fuel cell based on a bifunctional PtNiSx/CB catalyst not only transformed chemical energy into electric energy but also converted HMF into value-added 2,5-furandicarboxylic (FDCA).

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