High Ethanol Production Research Articles

Enhanced high temperature ethanol production using newly isolated thermotolerant yeast Pichia kudriavzevii NUPHS from Thailand

Enhanced high temperature ethanol production using newly isolated thermotolerant yeast Pichia kudriavzevii NUPHS from Thailand

Kluyveromyces marxianus: Current State of Omics Studies, Strain Improvement Strategy and Potential Industrial Implementation

Bioethanol is considered an excellent alternative to fossil fuels, since it importantly contributes to the reduced consumption of crude oil, and to the alleviation of environmental pollution. Up to now, the baker yeast Saccharomyces cerevisiae is the most common eukaryotic microorganism used in ethanol production. The inability of S. cerevisiae to grow on pentoses, however, hinders its effective growth on plant biomass hydrolysates, which contain large amounts of C5 and C12 sugars. The industrial-scale bioprocessing requires high temperature bioreactors, diverse carbon sources, and the high titer production of volatile compounds. These criteria indicate that the search for alternative microbes possessing useful traits that meet the required standards of bioethanol production is necessary. Compared to other yeasts, Kluyveromyces marxianus has several advantages over others, e.g., it could grow on a broad spectrum of substrates (C5, C6 and C12 sugars); tolerate high temperature, toxins, and a wide range of pH values; and produce volatile short-chain ester. K. marxianus also shows a high ethanol production rate at high temperature and is a Crabtree-negative species. These attributes make K. marxianus promising as an industrial host for the biosynthesis of biofuels and other valuable chemicals.

Potential of Candida glabrata from ragi as a bioethanol producer using selected carbohydrate substrates

Abstract. Vincent M, Johnny Q, Adeni DSA, Suhaili N. 2020. Potential of Candida glabrata from ragi as a bioethanol producer using selected carbohydrate substrates. Nusantara Bioscience 12: 1-10. The flexibility and efficiency of fermenting microorganisms to convert substrates to ethanol are important factors in achieving high bioethanol yields during ethanolic fermentation. In this study, Candida glabrata, a common yeast found in fermented food, was evaluated in terms of its capability to produce ethanol using different types of carbohydrates, which included simple saccharides (glucose, maltose, sucrose), polysaccharides (starch and cellulose) and complex carbohydrates (total sago effluent, TSE). Our results indicated that C. glabrata was able to efficiently produce ethanol from glucose at 79.84% TEY (Theoretical Ethanol Yield). The ethanol production from sucrose was low, which was only 6.44% TEY, while no ethanol was produced from maltose. Meanwhile, for complex carbohydrate substrates such as starch and cellulose, ethanol was produced only when supplementary enzymes were introduced. Simultaneous Saccharification and Fermentation (SSF) of starch dosed with amylases resulted in an ethanol yield of 55.08% TEY, whilst SSF of cellulose dosed with cellulases yielded a TEY of 31.41%. When SSF was performed on TSE dosed with amylases and cellulases, the highest ethanol production was recorded within 24 h, with a yield of 23.36% TEY. Lactic acid and acetic acid were found to be at minimal levels throughout the fermentation period, indicating an efficient ethanol conversion. A notable increase in C. glabrata biomass was observed in cultures fed with glucose, starch (with supplementary amylases), and TSE (with supplementary amylases and cellulases). The current study indicates that C. glabrata can be used for bioethanol production from glucose, polysaccharides, and complex starchy lignocellulosic substrates such as TSE via SSF.

Evaluation of ethanol tolerance in relation to intracellular storage compounds of Saccharomyces cerevisiae using FT-IR spectroscopy

During ethanol fermentation, ethanol accumulates in the medium and becomes a significant stress factor for yeast. Trehalose and glycogen are major carbohydrate storages and presumably protect cells from such stress conditions. In this study, batch cultivations of wild and adapted Saccharomyces cerevisiae were performed to evaluate the fermentation kinetics and carbohydrate storages, interrelatedly. Trehalose and glycogen were determined by both High Performance Liquid Chromatography (HPLC) and Fourier Transform-Infrared (FT-IR) spectroscopy for comparison. The obtained maximum trehalose and glycogen (7.5 and 10.5 %) contents of the adapted strain was remarkably higher compared to the wild strain (5 and 6.5 %). The adapted S. cerevisiae displayed an enhanced fermentation stresses coping ability resulting in a higher ethanol productivity (2.03 vs 1.65 g ethanol/h) as well as higher ethanol titer (7.7 vs 6.4 %). This study contributes to the understanding of the cellular response of S. cerevisiae cells to fermentation stresses in relation to culture history together with the evaluation of fermentation performance, as well as the process kinetics. This study also confirms that FT-IR spectroscopy of whole S. cerevisiae cells for determination of storage compounds without pretreatment has valuable advantages compared to HPLC with intensive sample handling.

Effect of microaeration on cell growth and glucose/xylose fermentation of Kluyveromyces marxianus from the imitate lignocellulosic-derived hydrolysate

The inhibitory effect of toxic byproducts mainly derived from the pretreatment of lignocellulosic biomass is one of the limiting factors hindering industrial application. In this work, a simple yet practicable aeration strategy was proposed to enhance microbial tolerance to inhibitors, including formic acid, acetic acid, furfural, and 5-hydroxymethyl furfural (5-HMF). Batch fermentation by Kluyveromyces marxianus CICC 1727−5 using xylose and glucose alone and in combination under different aeration conditions coupled with multiple inhibitors was performed. The fermentation time and residual xylose significantly decreased with high xylitol production (0.7 g/g) and high ethanol production (0.42 g/g) at an aeration rate of 0.5 vvm. The postglucose effect was effectively relieved during co-fermentation by the microaeration strategy. Transcriptomics analysis was performed to determine the mechanism of inhibitor resistance. Transcription of genes related to DNA replication, protein processing, carbon metabolism, biosynthesis of the ribosome, amino acids, peroxidase, sterols, and unsaturated fatty acids were significantly upregulated accompanied by downregulated expression of genes related to autophagy under aeration conditions in the presence of multiple inhibitors. These results provide a valuable reference for future studies on biofuel fermentation from lignocellulosic biomass by a facultative fermenting microbe.

Recycling of Black Liquor for Treating Sugarcane Bagasse at Low Temperature to Attain High Ethanol Production without Washing Step

Alkaline pretreatment has been commonly used for bioconversion of lignocellulose into fuel ethanol due to its gentle condition. However, the large quantity of water consumption and wastewater generation from the pretreatment and washing steps have been two bottleneck problems for the practical application of alkaline pretreatment. In order to save water consumption and reduce wastewater generation, black liquor (BL) generated in the sodium hydroxide (NaOH) pretreatment process was recycled for pretreating sugarcane bagasse (SCB), and the BL-NaOH-treated SCB without being washed was directly enzymatically hydrolyzed and fermented. After 120-h fed-batch enzymatic hydrolysis with the addition of 20 FPU cellulase/g cellulose and 2.51 μL Tween80/mL hydrolytic slurry, the maximum glucose concentration and enzymatic hydrolysis efficiency achieved 99.95 g/L and 71.02%, respectively. After 36-h fermentation with the domesticated Saccharomyces cerevisiae, the ethanol production reached 44.53 g/L, which amounted to 87.35% of theoretical ethanol yield. Compared with other water-saving and wastewater-reducing alkaline pretreatments, this technology saved more than 20% water consumption and reduced over 20% wastewater discharge. It provides a promising applied technology for cellulosic ethanol production.

Evaluating the Engineered Saccharomyces cerevisiae With High Spermidine Contents for Increased Tolerance to Lactic, Succinic, and Malic Acids and Increased Xylose Fermentation

Saccharomyces cerevisiae is a promising candidate for production of organic acids as it is more tolerant to these acids than the prokaryotes. However, the large-scale production of organic acids from lignocellulosic biomass is limited by their accumulation in the growth medium and inability of xylose fermentation by S. cerevisiae. Here we showed that high intracellular spermidine (SPD) contents confers enhanced tolerance to lactic, succinic, and malic acids in S. cerevisiae. Specifically, in the presence of 20 g/L malic acid, the maximum specific growth rate and dry cell weight of a S. cerevisiae with two fold higher SPD content were 40% and 36% higher than those of the control strain. When a xylose assimilation pathway was introduced into an engineered strain with high SPD content, the resulting S. cerevisiae strain exhibited 23∼47% higher xylose consumption rate and 6∼16% higher ethanol productivity than those of the control strain during the four times of repeated-batch fermentations using a mixture of glucose and xylose as carbon sources. These results suggest that the strain developed in this study would serve as a platform strain for production of organic acids.

Biochemical, physicochemical and melissopalynological analyses of two multifloral honey types from Brazil and their influence on mead production

The present work aimed to evaluate the biochemical, physicochemical and melissopalynological characteristics of two honey types obtained from the same production period (a light one and a dark one) and to apply them in the fermentative process of mead by three yeasts (Saccharomyces cerevisiae Montrachet, Saccharomyces bayanus Premier Blanc and Saccharomyces cerevisiae Safbrew T-58), incubated at 30 °C and 150 rpm for 24 h. The fermentations were carried out in 500 mL Erlenmeyer flasks containing honey must (30 oBrix), supplemented with yeast extract (5 g.L−1), malt extract (5 g.L−1), peptone (10 g.L−1), magnesium chloride (0.05 g.L−1), ammonium sulfate (0.3 g. L−1) and ammonium phosphate (0.05 g.L−1), inoculated with an initial culture of 106 cells. mL−1 and incubated at 30 °C for 264 h. A difference in the honey’s melissopalynological profile was observed, as well as a consequent difference in the physicochemical characteristics. Higher cell growth was observed: S. cerevisiae Montrachet (9.5 x 107 cells.mL−1, 72 h), S. bayanus Premier Blanc (9.2 x 107 cells.mL−1, 72 h) and S. cerevisiae Safbrew T-58 (6.1 x 107 cells.mL−1, 96 h), as well as a higher substrate consumption (80.7, 86.3 and 73.8%) and higher ethanol production (14.0, 15.0 and 12.7%), respectively, in the fermentation of the must with dark honey.

Effects of Additional Xylanase on Saccharification and Ethanol Fermentation of Ammonia-Pretreated Corn Stover and Rice Straw

Synergistic effect of cellulase and hemicellulase (xylanase) was evaluated because lignocellulosic material is a heterogeneous complex of cellulose and hemicellulose. Various effects of HTec2 addition on enzymatic saccharification and fermentation were evaluated using two different substrates such as corn stover and rice straw. Corn stover and rice straw were pretreated by the LMAA (low-moisture anhydrous ammonia) method at the preselected same conditions (90 °C, 120 h, moisture content = 50%, NH3 loading = 0.1 g NH3/g). It was observed that the enzymatic saccharification yield of pretreated corn stover (76.4% for glucan digestibility) was higher than that of pretreated rice straw (70.9% for glucan) using CTec2 cellulase without HTec2 addition. Glucan digestibility of pretreated corn stover was significantly increased from 76.4% to 91.1% when the HTec2/CTec2 (v/v) increased from 0 to 10. However, it was interesting that the ethanol production was decreased from 89.9% to 76.3% for SSF and 118.0% to 87.9% for SSCF at higher HTec2/CTec2. As the glucan loading increased from 2.0% to 7.0%, the ethanol yields of both SSF and SSCF were decreased from 96.3% to 88.9% and from 116.6% to 92.4%, respectively. In addition, the smallest inoculum size (optical density of 0.25) resulted in the highest ethanol production (20.5 g/L).

Genome sequence of Acremonium strictum AAJ6 strain isolated from the Cerrado biome in Brazil and CAZymes expression in thermotolerant industrial yeast for ethanol production

Increased demand for biofuels promotes the search for new biomass-degrading fungi. Acremonium strictum is an environmentally widespread filamentous fungi found on plant debris; that secretes lignocellulose-degrading enzymes. A recently isolated A. strictum strain, AAJ6; native to the Brazilian Cerrado biome was evaluated for its capacity to degrade lignocellulosic substrates. In this study, whole-genome sequencing of AAJ6 was performed and 775 CAZy domains were identified which correlated to those of A. strictum strain DS1bioAY4a and other lignocellulolytic fungi; suggesting AAJ6 is a high CAZyme producer. We expressed the glycoside hydrolase families GH74 and GH3 from plasmid or genome-integrated to evaluate the ethanol production from cellulosic substrates in Brazilian industrial Saccharomyces cerevisiae strains (PE-2 and SA-1) evolved for thermotolerance (AMY12 and AMY35). Those expressing the genome-integrated enzymes showed the highest β-glucosidase activity and growth in medium with cellobiose at 40°C. The strain AGY005 (integrated cassettes) showed 19, 23 and 46% higher ethanol production in SHF, pSSF (partial hydrolysis SSF) and SSF processes, respectively, using Avicel, and ∼50% more ethanol using pre-treated sugarcane bagasse, compared to the strain with a plasmid-based expression. These results indicate the improved performance of thermotolerant industrial strains with genome-integrated CAZymes in the SSF process for 2G ethanol.

Construction of Recombinant Klebsiella pneumoniae to Increase Ethanol Production on Residual Glycerol Fed-Batch Cultivations.

K. pneumoniae BLh-1 strain was genetically modified aiming at obtaining high ethanol productivity in cultivations using residual glycerol from biodiesel synthesis as substrate. The recombinant strain K. pneumoniae Kp17 was obtained by inserting the multicopy plasmid pTOPOBL17 containing the AdhE gene, and its own promoter, from K. pneumoniae BLh-1. Influence of Fe2+ supplementation and initial glycerol concentration on culture conditions were analyzed, both in rotatory shaker and in batch bioreactors. In the bioreactor cultures, K. pneumoniae Kp17 strain produced 4.5gL-1 of ethanol (productivity of 0.50gL-1h-1 and yields of 0.15gg-1) after 24-h cultivation, corresponding to an increase of approximately 40% in ethanol concentration compared to wild strain, K. pneumoniae BLh-1. Best conditions were then applied in exponential fed-batch bioreactors, with final ethanol concentration of 17.30gL-1 (productivity of 0.59gL-1h-1 and yields of 0.16gg-1) after 30h of feeding, representing 11.5% of increment in titer of ethanol compared to the wild strain. Mutant cells kept 92.5% of the plasmids under batch in 24h, and 71.9% under fed-batch after 27h of exponential feeding. The findings in this work show the possibility of using a simple approach to genetically modify K. pneumoniae to be employed this versatile bacterium for the bioconversion of residual glycerol into ethanol.

Simulation and Performance Analysis of Integrated Gasification–Syngas Fermentation Plant for Lignocellulosic Ethanol Production

This study presents a new simulation model developed with ASPEN Plus of waste biomass gasification integrated with syngas fermentation and product recovery units for bioethanol production from garden waste as a lignocellulosic biomass. The simulation model includes three modules: gasification, fermentation, and ethanol recovery. A parametric analysis is carried out to investigate the effect of gasification temperature (500–1500 °C) and equivalence ratio (0.2–0.6) on the gasification performance and bioethanol production yield. The results reveal that, for efficient gasification and high ethanol production, the operating temperature range should be 700–1000 °C, as well as an equivalence ratio between 0.2 and 0.4. At optimal operating conditions, the bioethanol production yield is 0.114 kg/h per 1 kg/h input garden waste with 50% moisture content. It is worth mentioning that this parameter increases to 0.217 kgbioethanol/kggarden waste under dry-based conditions.

Selection and oenological comparison of Taiwan Black Queen grape wine yeasts

More than hundreds of private wineries have been established since the Taiwan Tobacco and Alcohol Administration Act was enacted on April 19, 2000. It is then essential to screen local wine yeast in order to develop quality wine with unique flavor. Black Queen grape is a main ingredient for red wine brewing in Taiwan. In this study, ethanol productivity of yeasts isolated from spontaneous fermentation of Black Queen grape must (17 and 30 °Brix) was determined. Seven yeasts identified as Saccharomyces cerevisiae by Biolog System with higher ethanol productivity were individually inoculated into Black Queen grape must to undergo fermentation at 25°C for 14 days. The ethanol contents and volatile acidity in wine were above 15% (v/v) and below 0.7 g/L, respectively. Compared to commercial wine yeasts A, B and C, HP01 fermented red wine contained the highest total ester content, color intensity, taste grade, and overall preference value. On the other hand, HS13 fermented red wine contained the highest ethanol, higher alcohols, fatty acids and phenolic compounds content. The mtDNA restriction fragments profiles of these two wine yeast strains were different from those of other yeast strains. Due to their superiority in oenological characteristics, HP01 and HS13 can be applied in Black Queen red wine brewing to produce red wine with unique flavor.

Improvement in Ethanol Yield from Lignocellulo-Starch Biomass using Saccharomyces cerevisiae alone or its Co-culture with Scheffersomyces stipitis

Background:Literature on ethanol production from Lignocellulo-Starch Biomass (LCSB) containing starch besides cellulose and hemicellulose, is scanty. Fed-Batch Separate Hydrolysis And Fermentation (F-SHF) was earlier found more beneficial than Fed-Batch Simultaneous Saccharification and Fermentation (F-SSF).Objective:The study aimed at modification of the saccharification and fermentation strategies by including a prehydrolysis step prior to the SSF and compared the ethanol yields with co-culture fermentation using hexose-fermenting Saccharomyces cerevisiae and pentose-fermenting Scheffersomyces stipitis.Methods:Fed-batch hybrid-SSF and Fed-Batch Separate Hydrolysis and Co-culture Fermentation (F-SHCF) in improving ethanol yield from Steam (ST) or Dilute Sulfuric Acid (DSA) pretreated LCSBs (peels of root and vegetable crops) were studied.Results:There was a progressive build-up of ethanol during F-HSSF up to 72h and further production up to 120h was negligible, with no difference among pretreatments. Despite very high ethanol production in the initial 24h of fermentation by S.cerevisiae under F-SHCF, the further increase was negligible. A rapid hike in ethanol production was observed when S. stipitis was also supplemented because of xylose conversion to ethanol.Conclusion:While ST gave higher ethanol (296-323 ml/kg) than DSA under F-HSSF, the latter was advantageous under F-SHCF for certain residues. Prehydrolysis (24h; 50°C) enhanced initial sugar levels favouring fast fermentation and subsequent saccharification and fermentation occurred concurrently at 37°C for 120h, thus leading to energy saving and hence F-HSSF was advantageous. Owing to the low hemicellulose content in LCSBs, the relative advantage of co-culture fermentation over monoculture fermentation was not significant.

Stress-driven dynamic regulation of multiple tolerance genes improves robustness and productive capacity of Saccharomyces cerevisiae in industrial lignocellulose fermentation

Yeast productivity in lignocellulosic ethanol fermentation is clearly impeded by stress. Enhancing the robustness of xylose-fermenting yeast is important for improving lignocellulosic ethanol production. In this study, the glutathione biosynthesis pathway and acetic acid degradation pathway were strengthened to enhance yeast tolerance to stress due to elevated reactive oxygen species (ROS) and acetic acid. Dynamic feedback regulation of the anti-stress genetic circuits was achieved using stress-driven promoters discovered from the transcriptome to maintain low intracellular ROS, relieve the metabolic burden, and ultimately improve the robustness and ethanol production of yeast. The cell growth, xylose utilization and ethanol production of the engineered strain were enhanced under both stress and nonstress conditions. The engineered strain showed 49.5% and 17.5% higher ethanol productivity in laboratory media and industrial lignocellulosic media, respectively, at 36 °C compared with the parent strain. This study provides novel insights on the rational design and construction of feedback genetic circuits for dynamically improving yeast robustness.

Evaluation of the Fermentative Capacity of Saccharomyces cerevisiae CAT-1 and BB9 Strains and Pichia kudriavzevii BB2 at Simulated Industrial Conditions.

The search for promising yeasts that surpass the fermentative capacity of commercial strains, such as Saccharomyces cerevisiae CAT-1, is of great importance for industrial ethanol processes in the world. Two yeasts, Pichia kudriavzevii BB2 and Saccharomyces cerevisiae BB9, were evaluated in comparison to the industrial yeast S. cerevisiae CAT-1. The objective was to evaluate the performance profile of the three studied strains in terms of growth, substrate consumption, and metabolite formation, aiming to determine their behaviour in different media and pH conditions. The results showed that under cultivation conditions simulating the medium used in the industrial process (must at 22° Brix at pH 3.0) the highest ethanol productivity was 0.41gL-1h-1 for S. cerevisiae CAT-1, compared to 0.11g L-1 h-1 and 0.16g L-1 h-1 for P. kudriavzevii and S. cerevisiae BB2, respectively. S. cerevisiae CAT-1 produced three times more ethanol in must at pH 3.0 (28.30g L-1) and in mineral medium at pH 3.0 (29.17g L-1) and 5.0 (30.70g L-1) when compared to the value obtained in sugarcane must pH 3.0 (9.89g L-1). It was concluded that S. cerevisiae CAT-1 was not limited by the variation in pH in the mineral medium due to its nutritional composition, guaranteeing better performance of the yeast even in the presence of stressors. Only S. cerevisiae CAT-1 expressed he constitutive invertase enzyme, which is responsible for hydrolysing the sucrose contained in the must.

Population dynamics of Saccharomyces cerevisiae PE-2 and CAT-1 in CO-culture for the production of ethanol

In the Brazilian industries, the inoculum used throughout the harvest of ethanol production consists of a combination of two or more yeast strains. The combination of yeasts may influence in the metabolic pathways of microorganisms and increase the yields and production rates of some compounds. In biotechnological processes with co-culture, one microorganism can prevail over the other. Therefore, the knowledge about how the population dynamics occurs during fermentation allows modifications in the process in order to obtain higher yields and to achieve greater fermentative efficiency. The aim of this study was to investigate the fermentation with synthetic sugar cane broth in co-culture of Saccharomyces cerevisiae strains CAT-1 and PE-2 followed by molecular fermentation monitoring. The concentration of biomass, ethanol, glycerol, acetic acid and residual sucrose were monitored to verify the influence of different combinations during the fermentation. The mixture of CAT-1 and PE-2 presented the highest ethanol production, with higher performance of fermentative parameters than pure cultures

Entrapped Psychrotolerant Yeast Cells within Pine Sawdust for Low Temperature Wine Making: Impact on Wine Quality.

An alternative methodology is proposed for low temperature winemaking using freeze-dried raw materials. Pine sawdust was delignified and the received porous cellulosic material was applied as immobilization carrier of the psychrotolerant yeast strain Saccharomyces cerevisiae AXAZ-1. The immobilization of yeast cells was examined and verified by scanning electron microscopy (SEM). The immobilized biocatalyst and high-gravity grape must were separately freeze-dried without cryoprotectants and stored at room temperature (20–22 °C) for 3 months. The effect of storage on the fermentation efficiency of the immobilized biocatalyst at low temperatures (1–10 °C), as well as on the aromatic characteristics of the produced wines was evaluated. Storage time had no significant effect on the fermentation efficiency of the biocatalyst resulting in most cases in high ethanol production 13.8–14.8% v/v. The volatile fraction of the produced wines was examined using headspace solid-phase microextraction (HS-SPME) followed by gas chromatography mass spectrometry (GC/MS). GC-MS/SPME analysis along with the organoleptic evaluation revealed in all produced wines a plethora of fresh and fruit aromatic notes. To conclude, fermentation kinetics and aromatic profile evaluation encourages the production of high-quality sweet wines at low temperatures using pine sawdust (Pinus halepensis) entrapped yeast cells as a promoter.

Effects of various inhibitory substances and immobilization on ethanol production efficiency of a thermotolerant Pichia kudriavzevii

BackgroundAlthough bioethanol production has been gaining worldwide attention as an alternative to fossil fuel, ethanol productivities and yields are still limited due to the susceptibility of fermentation microorganisms to various stress and inhibitory substances. There is therefore an unmet need to search for multi-stress-tolerant organisms to improve ethanol productivity and reduce production cost, particularly when lignocellulosic hydrolysates are used as the feedstock.ResultsHere, we have characterized a previously isolated Pichia kudriavzevii LC375240 strain which is thermotolerant to high temperatures of 37 °C and 42 °C. More excitingly, growth and ethanol productivity of this strain exhibit strong tolerance to multiple stresses such as acetic acid, furfural, formic acid, H2O2 and high concentration of ethanol at 42 °C. In addition, simple immobilization of LC375240 on corncobs resulted to a more stable and higher efficient ethanol production for successive four cycles of repeated batch fermentation at 42 °C.ConclusionThe feature of being thermotolerant and multi-stress-tolerant is unique to P. kudriavzevii LC375240 and makes it a good candidate for second-generation bioethanol fermentation as well as for investigating the molecular basis underlying the robust stress tolerance. Immobilization of P. kudriavzevii LC375240 on corncobs is another option for cheap and high ethanol productivity.

An effective strategy for dual enhancements on bioethanol production and trace metal removal using Miscanthus straws

Lead (Pb) is one of the most hazardous substances contaminating water source and agricultural lands, and Miscanthus is a leading bioenergy crop providing enormous lignocellulose residues convertible for bioethanol and biochemicals. Using two distinct Miscanthus straws, this study compared various chemical pretreatments to obtain relatively high cellulosic ethanol production. All remained solid wastes were then employed for Pb adsorption under different incubation conditions (pH, initial concentration, temperature, etc). By comparison, the solid residues were of remarkably higher Pb adsorption capacity and removal rates than those of raw materials. Notably, the optimal one-step alkali pretreatment could not only lead to high bioethanol yield, but the remaining solid residues from final yeast fermentation were of the highest Pb adsorption among all pretreatments performed in this study. Chemical analyses revealed that the solid residues from the optimal alkali pretreatment could act as active biosorbents for Pb adsorption via typical chemical binding manner, and they also exhibited much larger surface area and pore volume relative to the raw materials, interpreting why they were of significantly higher Pb adsorption. Hence, this study has demonstrated a powerful strategy to use full Miscanthus straws for both enhanced cellulosic ethanol production and improved biosorbent activity for trace metal removal without any biomass waste release into the environment.