Bioethanol Feedstock Research Articles

Optimized bioethanol production from Lemna minuta biomass harvested from polluted water via acid and enzymatic hydrolysis

The contamination of water bodies through domestic, agricultural, and industrial discharges remains a critical environmental challenge, leading to eutrophication and harmful impacts on aquatic ecosystems and public health. In response, phytoremediation, which utilizes aquatic plants for pollutant removal, have gained attention. This study investigates the potential of Lemna minuta biomass, harvested from a polluted pond, for bioethanol production. The research evaluates carbohydrate content and explores the efficiency of acid and enzymatic hydrolysis in converting the biomass into fermentable sugars. The study’s findings reveal that Lemna minuta exhibits a carbohydrate content of 36.46 ± 1.69%. Acid hydrolysis demonstrated a high conversion efficiency, with optimal conditions achieving up to 99.20% efficiency and 18.09 g L−1 total reducing sugars. Enzymatic hydrolysis, while effective, yielded lower efficiencies, indicating the need for further optimization. Fermentation tests using Saccharomyces cerevisiae chardonnay resulted in ethanol production of 1.5 g L−1, highlighting the potential of Lemna minuta as a sustainable bioethanol feedstock. These findings highlight the potential of Lemna minuta as a sustainable feedstock for bioethanol production while contributing to environmental remediation, reinforcing its dual role in renewable energy and ecosystem restoration.

Cyanobacterial phycoremediation: a sustainable approach to dairy wastewater management

ABSTRACT The dairy industry is a significant sector within the food industries, known for its high-water consumption and consequent generation of dairy wastewater (DWW), which is rich in pollutants like Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD). Improper disposal of DWW poses serious environmental challenges, including eutrophication and highlighting the need for sustainable biological treatment methods. This study investigates the potential of indigenous cyanobacterial strains Oscillatoria pseudogeminata, Oscillatoria proteus, Oscillatoria trichoides, and Lyngbya ceylanica for the bioremediation of DWW. Under controlled laboratory conditions, these strains were assessed for their uptake capabilities for 15 days. Results indicated that L. ceylanica significantly reduced (approx. 70%, P < .05) in key pollutants such as ammonia, nitrate, and phosphate compared to other strains. Biochemical analyses indicated a decrease in biomass, chlorophyll a, carotenoids, proteins, and carbohydrates in DWW relative to the growth of cyanobacteria in BG 11 media. This decline may hinder the effectiveness of cyanobacterial in wastewater remediation. The findings highlight the efficacy of selected cyanobacteria in nutrient removal from DWW, emphasizing their dual role in nutrient uptake through biosorption mechanism and biomass generation. The results pave the way for innovative biotechnological applications such as biofertilizers and feedstock for bioethanol/ biodiesel production, thus promoting more sustainable management practices within the dairy industry.

A Review of the Technological Aspects and Process Optimization of Bioethanol Production From Corn Stover Biomass: Pretreatment Process, Hydrolysis, Fermentation, Purification Process, and Future Perspective

ABSTRACTBioethanol, a sustainable energy solution derived from renewable biomass, has gained prominence, with corn stover emerging as a substantial biomass resource in Indonesia. Corn stover, a corn residue, is one of the top three agricultural wastes worldwide and is abundantly available. However, a significant portion of corn stover is burned in fields rather than utilized for bioethanol production, whereas it has potential as a bioethanol feedstock. As the world strives to realize sustainable and environmentally friendly energy security, bioethanol production from corn stover can be one of the solutions to be developed. Nonetheless, the current immaturity of bioethanol production technology is one of the causes of large‐scale production failure. The present paper comprehensively reviews the technological aspects and process optimization of bioethanol production using corn stover as a feedstock comprising pretreatment, hydrolysis, fermentation, and bioethanol purification processes. According to our critical review, ammonia fiber expansion (AFEX) pretreatment is the most effective conventional pretreatment, with glucose yield up to 90%. Moreover, ultrasound appears to be the most viable option for nonconventional pretreatment of corn stover for producing bioethanol. However, combining ultrasound pretreatment and dilute aqueous ammonia produced 80.6% sugar output. Furthermore, enzymatic hydrolysis emerges as the most effective saccharification, yielding up to 81.39%. Moreover, the fermentation process of corn stover with the saccharification and co‐fermentation (SScF) method and the process optimization with response surface methodology (RSM) could produce bioethanol with a concentration of up to 59.8 g/L and 92.07% ethanol yield, respectively. This review also reveals that pervaporation for the purification process is the best choice for producing bioethanol with high purity up to &gt; 99%. In addition, this method could reduce the energy used by 6.6% lower, 24.2% lower carbon footprint, and have the lowest total capital and production costs compared to conventional molecular sieves and extractive distillation. We believe this review article can provide a reference for selecting the best bioethanol production process from corn stover for further research.

Fermentation of Biomass and Residues from Brazilian Agriculture for 2G Bioethanol Production.

Brazil is one of the world's leading producers of staple foods and bioethanol. Lignocellulosic residual sources have been proposed as a promising feedstock for 2G bioethanol and to reduce competition between food and fuels. This work aims to discuss residual biomass from Brazilian agriculture as lignocellulosic feedstock for 2G bioethanol production as bagasse, stalk, stem, and peels, using biorefining concepts to increase ethanol yields. Herein, we focused on biomass chemical characteristics, pretreatment, microorganisms, and optimization of process parameters that define ethanol yields for bench-scale fermentation. Although several techniques, such as carbon capture, linking enzymes to supports, and a consortium of microorganisms, emerge as future alternatives in bioethanol synthesis, these technologies entail necessary optimization efforts before commercial availability. Overcoming these challenges is essential to linking technological innovation to synthesizing environmentally friendly fuels and searching other biomass wastes for 2G bioethanol to increase the biofuel industry's potential. Thus, this work is the first to discuss underutilized lignocellulosic feedstock from other agrifoods beyond sugar cane or corn, such as babassu, tobacco, cassava, orange, cotton, soybean, potatoes, and rice. Residual biomasses combined with optimized pretreatment and mixed fermentation increase hydrolysis efficiency, fermentation, and purification. Therefore, more than a product with a high added value, bioethanol synthesis from Brazilian residual biomass prevents waste production.

Investigation of the effect of specific gravity and pH on the fermentation period of a single and combined algae species as a potential bioethanol feedstock

Algae has garnered significant attention as a promising biomass source for bioethanol production and as a solution to sustainability issues. Nevertheless, the disruption of complex carbohydrates required for yeast fermentation occurs during algae cultivation. The fermentation process, which is critical for producing bioethanol as a cost-effective and environmentally friendly alternative fuel, may be improved by meticulously managing the parameters that influence fermentation, such as specific gravity and pH. Bioethanol was produced from algae species (Navicula sp., Oscillatoria sp. and diatoms) using simultaneous saccharification and fermentation (SSF) processes. A control, single and combined algal species were prepared in the following formation: Oscillatoria sp. and Navicula sp. (sample A), Oscillatoria sp. (sample B), diatom and Oscillatoria sp. (sample C), Navicula sp. (sample D), and diatoms, Navicula sp. and Oscillatoria sp (sample E). The daily bioethanol concentrations in the fermentation medium were measured using a digital optical refractometer, and a Two-way ANOVA analysis (p < 0.05) was conducted to determine the differences between the period of fermentation and the bioethanol concentration. Additionally, the pH and specific gravity were assessed. The Two-way ANOVA analysis conducted indicated that the F-values surpassed the F-critical values and the p-values were all notably below 0.05, suggesting a statistically significant distinction between the samples in their fermentation periods and bioethanol concentration. The highest concentration was observed in sample E at 39.53 g/L, followed by samples C and D at 37.36 g/L, samples A and B at 35.10 g/L, and the control at 4.78 g/L. The findings showed that mixed cultures could potentially improve ethanol yield. The optimal fermentation period was determined to be 72 h. The pH levels in the control and algae samples varied between 6.5 and 6.7 and 7.06 to 8.42, respectively. The specific gravity in the control and algae samples ranged from 1.003 to 1.004 and 1.023 to 1.037, respectively. During algae fermentation, specific gravity initially increased, then stabilized before decreasing. pH levels correlated with fermentation duration. Understanding these factors is crucial for maximizing bioethanol production. This discovery could lead to exploring how different algae species interact to improve cultivation methods.

Chemical Composition and Carbohydrate Characterization of Beach-Cast Marine Macrophytes from the Mexican Caribbean: Implications for Potential Bioethanol Production

Marine macrophytes are considered promising biomass for bioethanol production. The increases in anthropogenic nutrients and climate change have caused unprecedented blooming of ‘sargasso’ across the Atlantic since 2011. This biomass reaches the Caribbean Sea, stranding in large amounts along shorelines, and creating a serious waste management problem. The knowledge of its chemical composition is important to assess whether this material could serve as feedstock for third-generation bioethanol. The beach-cast marine macrophytes collected on the Mexican Caribbean coast in December 2018 were composed of brown seaweeds and a seagrass (23.5 and 76.5% relative abundance, respectively) including Sargassum fluitans, Sargassum natans I, Sargassum natans VIII, Turbinaria turbinata, and the angiosperm Syringodium filiforme. For valorization purposes, glucans, non-glucans carbohydrates and lignin were determined. Besides its abundance, underutilization, and low-cost this whole biomass may have potential as a promising raw material for third-generation bioethanol because it contains easily fermentable glucose such as mannitol (36.3% in whole biomass and 56% in the Sargassum species) and cellulose (36.3% on average). Other specific carbohydrates such as alginate (20–31%) and fucoidan (9.1–8.2%) were present in smaller amounts but they can also be converted to fermentable sugars with the proper methodology. Some advantages and limitations for the potential production of third-generation bioethanol from this biomass are discussed.

Engineered Chlorella vulgaris improves bioethanol production and promises prebiotic application.

Microalgal biomass for biofuel production, integration into functional food, and feed supplementation has generated substantial interest worldwide due to its high growth rate, non-competitiveness for agronomic land, ease of cultivation in containments, and presence of several bioactive molecules. In this study, genetic engineering tools were employed to develop transgenic lines of freshwater microalga Chlorella vulgaris with a higher starch content, by up-regulating ADP-glucose pyrophosphorylase (AGPase), which is a rate-limiting enzyme in starch biosynthesis. Expression of the Escherichia coli glgC (AGPase homolog) gene in C. vulgaris led to an increase in total carbohydrate content up to 45.1% (dry cell weight, DCW) in the transgenic line as compared to 34.2% (DCW) in the untransformed control. The starch content improved up to 16% (DCW) in the transgenic alga compared to 10% (DCW) in the control. However, the content of total lipid, carotenoid, and chlorophyll decreased differentially in the transgenic lines. The carbohydrate-rich biomass from the transgenic algal line was used to produce bioethanol via yeast fermentation, which resulted in a higher ethanol yield of 82.82mg/L as compared to 54.41mg/L from the untransformed control. The in vitro digestibility of the transgenic algal starch revealed a resistant starch content of up to 7% of total starch. Faster growth of four probiotic bacterial species along with a lowering of the pH of the growth medium indicated transgenic alga to exert a positive prebiotic effect. Taken together, the study documents the utilization of genetically engineered C. vulgaris with enriched carbohydrates as bioethanol feedstock and functional food ingredients.

Optimal agricultural structure allocation based on carbon source/sink accounting

China has implemented policies to promote fuel ethanol development and achieve its dual-carbon goal. Under the policy, the significant modifications will occur in the allocation of land use resources within ethanol raw material cultivation regions. In the process of land use change, ensuring food provision and protecting the regional carbon sink are also crucial for sustainable development. This study explores carbon distribution in the Guiping section of the Yujiang River basin, where bioethanol raw materials are cultivated. Using the CLUE-S model, a multi-objective model prioritizing economic and ecological benefits is constructed. Four scenarios (i.e., the natural expansion scenario (NES); the food conservation scenario (FCS); the bioethanol feedstock conservation scenario (BCS), and the carbon sinks conservation scenario (CCS) are simulated, predicting land resource distribution by 2030. The total carbon sink decreased by 285.60 gC·m−2·a−1, showing a seasonal trend of higher levels in summer and lower levels in winter. In 2030, the total carbon sink decreased in the NES scenario, while it increased in the FCS and BCS scenarios. The CCS scenario had the largest increase, approximately 582.27 × 103 tC. These simulated scenarios consider various economic and environmental factors, providing a scientific basis for the efficient allocation of regional land resources. They also have significant implications for local energy, economic, and environmentally sustainable development, as well as promoting the achievement of carbon neutrality.

Biogas Generation from Cotton Waste

Abstract: The anaerobic treatability and methane generation potential of three altered cotton wastes namely, cotton stalks, cotton seed hull and cotton oil cake remained determined in batch reactors. In addition, the effects of nutrient and trace metal supplementation were similarly investigated. The conversion of organics of cotton stem into bioenergy could serve the dual part of renewable energy production and waste reduction. Composition analysis demonstrated that cotton stem is a suitable feedstock for both bioethanol and biogas production. Anaerobic digestion of cotton stem attained 40.35% total biogas with 12.76% increased net CH4 volume compared to co-digestion of cotton stem with buffalo dung. Chopped cotton waste was considered as prospected substrate for biogas production. Cotton stalk was used gradually to exchange gobar content as substrate. During the study of four months the digester performed well till 90% feeding of cotton waste substrate. The maximum biogas generation detected was 1.3 m3 ; this shows that chopped cotton wastehas the potential to generate biogas. However, the digester was choked repeatedly and the concern of repetitive chocking of digester needs to be addressed.

Comparative assessment of pre-treatment techniques and process economics on marine seaweed, Gelidium pusillum, for enhanced bioethanol production

Many researchers are actively investigating different pre-treatment methods on alternative energy sources for sustainable production of bioethanol. With abundant carbohydrates and ease of cultivation, Gelidium pusillum, seaweed biomass has gained attention as a bioethanol feedstock. In the present study, various combinatorial pre-treatment methods like ultrasonic-acid treatment, microwave-alkali treatment, and steam-organic solvent treatment were carried out on seaweed biomass and compared for their efficiency in bioethanol production. Physico-chemical changes of biomass were characterized using Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, and X-ray Diffraction. Among all pre-treatment methods, microwave-alkali treatment was found to be the most effective one and yielding fermentable sugars, sugar utilization efficiency, and ethanol concentration of 395 mg/g, 78.33 ± 0.98%, and 5.7 ± 0.19 g/L, respectively. Additionally, the process-economic analysis showed that Gelidium pusillum and microwave-alkali treatment could be scaled up to the industrial level with a production cost of $1.40 per liter of ethanol with minimal ecological impact.

Development of an Integrated Bioprocess System for Bioethanol and Arabitol Production from Sugar Beet Cossettes.

An innovative integrated bioprocess system for bioethanol production from raw sugar beet cossettes (SBC) and arabitol from remaining exhausted sugar beet cossettes (ESBC) was studied. This integrated three-stage bioprocess system is an example of the biorefinery concept to maximise the use of raw SBC for the production of high value-added products such as sugar alcohols and bioethanol. The first stage of the integrated bioprocess system was simultaneous sugar extraction from SBC and its alcoholic fermentation to produce bioethanol in an integrated bioreactor system (vertical column bioreactor and stirred tank bioreactor) containing a high-density suspension of yeast Saccharomyces cerevisiae (30 g/L). The second stage was the pretreatment of ESBC with dilute sulfuric acid to release fermentable sugars. The resulting liquid hydrolysate of ESBC was used in the third stage as a nutrient medium for arabitol production by non-Saccharomyces yeasts (Spathaspora passalidarum CBS 10155 and Spathaspora arborariae CBS 11463). The obtained results show that the efficiency of bioethanol production increased with increasing temperature and prolonged residence time in the integrated bioreactor system. The maximum bioethanol production efficiency (87.22 %) was observed at a time of 60 min and a temperature of 36 °C. Further increase in residence time (above 60 min) did not result in the significant increase of bioethanol production efficiency. Weak acid hydrolysis was used for ESBC pretreatment and the highest sugar yield was reached at 200 °C and residence time of 1 min. The inhibitors of the weak acid pretreatment were produced below bioprocess inhibition threshold. The use of the obtained liqiud phase of ESBC hydrolysate for the production of arabitol in the stirred tank bioreactor under constant aeration clearly showed that S. passalidarum CBS 10155 with 8.48 g/L of arabitol (YP/S=0.603 g/g and bioprocess productivity of 0.176 g/(L.h)) is a better arabitol producer than Spathaspora arborariae CBS 10155. An innovative integrated bioprocess system for the production of bioethanol and arabitol was developed based on the biorefinery concept. This three-stage bioprocess system shows great potential for maximum use of SBC as a feedstock for bioethanol and arabitol production and it could be an example of a sustainable 'zero waste' production system.

Bambusa tulda: A potential feedstock for bioethanol and its blending effects on the performance of spark ignition engine

Alternatives to conventional fuel sources must be investigated due to strict regulatory requirements and the depletion of fossil fuel supplies. As a result, of better transportation and population growth, the requirement for energy is increasing daily. Bioethanol may be used successfully to replace both gasoline and spark ignition engine diesel. Most nations blend 10% bioethanol with gasoline in automobiles. Several nations, notably India, have announced that they will soon begin blending 20% bioethanol with gasoline. Bambusa Tulda is used as a raw material for the extraction of bioethanol, which is a type of Indian bamboo. This study covers both the ethanol extraction from bamboo and the effects of various mixtures on spark-ignited engine performance. Four separate blends were developed on a volumetric basis at varying engine speeds, and the wide-open throttle was utilized to evaluate the performance and emissions of each mix with a constant compression ratio of 10:1. When bioethanol was enhanced, combustion efficiency, indicated power, engine power, mechanical efficiency, and volumetric efficiency all increased. Hydrocarbon, carbon monoxide, and carbon dioxide emissions decreased, while nitrogen oxide emissions increased. The engine performance of BE 15 was found to be the greatest among all the gasoline blends tested. According to this study, when nitrogen oxide emission control methods are applied, bamboo may be used as a feedstock for the manufacture of second-generation bioethanol. This invention offers a bioethanol production process that is good for environmental sustainability.

Optimization of Bioethanol Production from Cassava through Fermentation Stimulant with Addition of Alpha-Amylase Enzyme

Bioethanol, as a substitute for fuel, presents significant advantages such as environmentally friendly exhaust emissions, high octane value, and a reduction in the use of hazardous additives. The utilization of carbohydrate-rich alternatives as bioethanol feedstock is gaining prominence, particularly root vegetables like cassava. The objective of this research is to obtain bioethanol from cassava through a fermentation stimulant process involving cellulase enzyme and Saccharomyces caravisiase. In the long term, the overarching goal is to establish an alternative energy source with bioethanol production technology derived from cassava. This study comprises three treatments, incorporating the addition of alpha-amylase enzyme at 0.5, 0.1, and 0.15 mL, with a fermentation duration of 56 hours. The research findings reveal that the addition of 0.5 mL of alpha-amylase enzyme produces optimal bioethanol with the highest yield. These results not only underscore the potential of cassava as a primary bioethanol feedstock but also make a significant contribution to the development of efficient and sustainable bioethanol production technology.

Unlocking Indonesia's sweet sorghum potential: A techno-economic analysis of small-scale integrated sorghum-based fuel grade bioethanol industry

To expand the utilization of sweet sorghum as bioethanol feedstock, an initial study of the feasibility completed with techno-economic analysis of an integrated small-scale sweet sorghum-based bioethanol industry (capacity of 4 kL/d) located in East Java, Indonesia is exemplified in this paper. Bioethanol is produced from pressed sorghum juice, while other parts of the sorghum plant, i.e. grains, leaves, and residual biomass, are used to produce other valuable products such as sorghum flour, rice, bran, and biopellet. The feasibility of producing bioethanol from sweet sorghum as raw material can be achieved if all by-products and parts of sorghum that have not been utilized are also converted to valuable products. The results of techno-economic calculations show that the use of sweet sorghum for bioethanol and by-products is feasible to develop fuel grade bioethanol industry with an NPV of IDR 47.5 billion, IRR 28.0 %, and a payback period of 4.10 years.

Exploring the Utilization Potential of Spirogyra sp. Biomass for Ethanol Production: A Study on Saccharification Optimization and High-Temperature Ethanol Fermentation

Spirogyra sp. is one of the potential feedstocks for bioethanol production, owing to its high carbohydrate and low lignin contents. However, to date, its use has scarcely been reported, particularly in high-temperature ethanol fermentation. The present study investigated the use of Spirogyra biomass as a bioethanol feedstock by optimizing the conditions for biomass saccharification, followed by ethanol fermentation via thermotolerant yeasts, i.e., Saccahromyces cerevisiae DBKKU Y-53, Kluyveromyces marxianus DBKKU Y-102, and Pichia kudriazevii RZ8-1. The optimization of the algal biomass hydrolysis using response surface methodology (RSM) showed that a maximum total sugar production of 14.75 ± 0.13 g/L was attained using 2.67% (v/v) sulfuric acid, 7.97% (w/v) of biomass loading, and 20 min of hydrolysis time. The fermentation of Spirogyra sp. hydrolysate containing 20 g/L of total sugar at 37 °C showed that S. cerevisiae DBKKU Y-53, K. marxianus DBKKU Y-102, and P. kudriazevii RZ8-1 produced 4.05 ± 0.35 g/L, 4.48 ± 0.13 g/L, and 4.47 ± 0.19 g/L of ethanol, respectively. At 40 °C, lower ethanol production of 1.07 ± 0.47 g/L, 3.93 ± 0.24 g/L, and 3.97 ± 0.19 g/L, respectively, were observed. Nevertheless, P. kudriazevii RZ8-1 exhibited a promising potential for the further development of a high-temperature ethanol fermentation process.

Exploring hostel kitchen waste as feedstock for bioethanol and biogas production in a biorefinery setup

Waste to wealth is today’s need, as waste generation has become humongous challenge for mankind now. In the present study kitchen waste from the Institute, hostel mess is used as raw material for ethanol, biogas, and manure production in a bio-refinery system. In the first step of the biorefinery the kitchen waste, which contains approximately 35% carbohydrates, was pretreated with 0.5 % H2SO4 to release sugars required for fermentation and 3.6 mg/ml of reducing sugars, and 0.46 mg/ml of pentose sugar. Enzymatic hydrolysis of the un-hydrolyzed biomass remnant after acid pretreatment at 30 °C with crude amylase (enzyme activity: 45.36 U/min/ml) obtained from Aspergillus niger followed by hydrolysis at 55 °C with crude cellulase (enzyme activity: 36.25 U/min/ml) and xylanase activity (activity: 11.25 U/min/ml) obtained from Trichoderma reesei produced 1.64 mg/ml and 1.66 mg/ml hexose and pentose sugar, respectively. Fermentation of the hydrolysate with S. cerevisiae and Pistia stipitis produced a 2.43% (v/v) ethanol yield. Anaerobic digestion of the unutilized solid biomass produced 270 ml/Kg biogas and 63.35 gm/Kg dry soil nutrient enhancer. The study suggested that the kitchen waste-based economically viable bio-refinery setup can be developed for the eco-friendly management and production of various valuable products from kitchen waste.

Biorefining of corn stover for efficient production of bioethanol, biodiesel, biomethane, and value-added byproducts

The present study investigated an integrated biorefinery that employed corn stover as the feedstock for sustainable bioethanol, biodiesel, biogas, chitosan, glycerol, and animal feed production. Corn stover was initially subjected to dilute acid pretreatment (1.8 % v/v H2SO4, 121 °C, and 22 min) followed by enzymatic hydrolysis with a commercial cellulase (37 °C, 72 h) to promote the release of glucose (∼93 wt%) and xylose (∼89 wt%). Mucor indicus fungus was then employed to convert the released sugars into bioethanol, glycerol, and fungal biomass with yields of 0.38 g g−1, 36 mg g−1, and 0.51 g g−1, respectively. The biomass of M. indicus was processed to extract chitosan (6 mg g−1 fungal biomass) and lipids (297 mg g−1 fungal biomass). The lipid was subsequently converted to biodiesel via transesterification in the presence of HCl/ MeOH with the yield of 0.54 g g−1 fungal lipid. The defatted biomass residue was then converted to biogas with 81 % theoretical yield through anaerobic digestion. To ensure process circularity, the nutritional values of pretreated and hydrolyzed corn stover were also investigated with their suitability as livestock. It was determined that 158.1 thousand tons of dry corn stover, which was annually collectible in Iran, could be used for the production of 137.6 kg chitosan, 10.4 ton animal feed, 870.0 kg glycerol, 40.7 million litters ethanol, 2.8 million m3 biodiesel, and 449.2 million m3 biomethane. The utilization of the produced ethanol, biodiesel, and biomethane in transporting sector was shown to have the potential of facilitating 4.3 million tons of equivalent carbon dioxide and a 197.8 million dollars reduction of associated social costs.

Bioprospecting of novel ligninolytic bacteria for effective bioremediation of agricultural by-product and synthetic pollutant dyes

Lignin is a significant renewable carbon source that needs to be exploited to manufacture bio-ethanol and chemical feedstocks. Lignin mimicking methylene blue (MB) dye is widely used in industries and causes water pollution. Using kraft lignin, methylene blue, and guaiacol as a full carbon source, 27 lignin-degrading bacteria (LDB) were isolated from 12 distinct traditional organic manures for the current investigation. The ligninolytic potential of 27 lignin-degrading bacteria was assessed by qualitative and quantitative assay. In a qualitative plate assay, the LDB-25 strain produced the largest zone, measuring 6.32 ± 0.297, on MSM-L-kraft lignin plates, while the LDB-23 strain produced the largest zone, measuring 3.44 ± 0.413, on MSM-L-Guaiacol plates. The LDB-9 strain in MSM-L-kraft lignin broth was able to decolorize lignin to a maximum of 38.327 ± 0.011% in a quantitative lignin degradation assay, which was later verified by FTIR assay. In contrast, LDB-20 produced the highest decolorization (49.633 ± 0.017%) in the MSM-L-Methylene blue broth. The highest manganese peroxidase enzyme activity, measuring 6322.314 ± 0.034 U L−1, was found in the LDB-25 strain, while the highest laccase enzyme activity, measuring 1.5105 ± 0.017 U L−1, was found in the LDB-23 strain. A preliminary examination into the biodegradation of rice straw using effective LDB was carried out, and efficient lignin-degrading bacteria were identified using 16SrDNA sequencing. SEM investigations also supported lignin degradation. LDB-8 strain had the highest percentage of lignin degradation (52.86%), followed by LDB-25, LDB-20, and LDB-9. These lignin-degrading bacteria have the ability to significantly reduce lignin and lignin-analog environmental contaminants, therefore they can be further researched for effective bio-waste management mediated breakdown.

Process simulation-based scenario analysis of scaled-up bioethanol production from water hyacinth.

The online version contains supplementary material available at 10.1007/s13399-023-03891-w.

TaqMan-Based Duplex Real-Time PCR Approach for Analysis of Grain Composition (Zea mays - Sorghum bicolor) in Feedstock Flour Mixes for Bioethanol Production

Some U.S. bioethanol plants use a blend of maize and sorghum grains as feedstocks depending on availability and price. Knowledge of the grain composition of milled feedstock is beneficial for maximizing process efficiency and for potential future regulatory requirements. To analyze feedstock composition, we developed a duplex real-time PCR assay based on TaqMan probes for the simultaneous analysis of flour blends. For sorghum, the method amplified a sequence within the F-Box domain-containing protein and for maize, the method amplified a sequence of the high mobility group a (HMGa) proteins. To acquire fluorescent signals simultaneously, FAM and TAMRA fluorescent probes were used to label the sorghum- and maize-specific probes, respectively. Results showed that the primers and probes were highly specific for either maize or sorghum. The real-time duplex PCR assay was validated on simulated flour binary mixtures and was high in the precision and accuracy for the sorghum PCR system. Results with the established method showed specificity and sensitivity in quantifying sorghum composition in bioethanol feedstock mixtures.