Ethanol Production Process Research Articles

Yeast enhancement by mass mating and selective pressure for the integrated production process of first and second-generation ethanol

Second-generation ethanol production is a worldwide applicable technology with the potential to replace fossil fuels and contribute to sustainability. The incorporation of second-generation ethanol production in Brazilian biorefineries, besides the technological advantages, adds to the abundance of feedstock derived from the sugar and alcohol industry itself. However, developing yeast strains that resist the inhibitory conditions of the new substrate, potentiated by cellular recycling, is extremely necessary. The aim of the present work was to develop yeast strains by hybridization and selective pressure techniques, with multi-tolerant profile for the fed-batch fermentation process using a mixture of molasses and bagasse hydrolysate as substrate. Therefore, the mass crossing technique was carried out involving five strains of Saccharomyces cerevisiae, previously selected, for demonstrating high tolerance to fermentation from mixed-must composed of lignocellulosic hydrolysate and sugarcane molasses. The culture resulting from the mass mating was followed by a selective pressure during 51 generations, generating enrichment of more tolerant strains. Employing microplate growth evaluation (optical density [DO] 600 nm), ten evolved isolates were selected, which were submitted to lab scale fermentation, simulating industrial conditions to the maximum. In the end, it was possible to highlight a lineage (C8E1-13T) presenting trehalose reserve content significantly higher than the other lineages evaluated, thus demonstrating the generation of an improved phenotype.

Comparison of adsorption potential of methylene blue and 17β-stradiol on biochar, activated biochar and catalytic biochar from lignocellulosic waste

This work compares the adsorption capacity of methylene blue (MB) and 17β-stradiol (17β-S) onto biochar (B), activated biochar (AB) and catalytic biochar (CB), obtained through pyrolysis of residual lignin of the second-generation (2G) ethanol production process from a sugarcane industry. K2CO3 was used as activating agent and catalyst. Biochars were characterized by the techniques of point of zero charge, nitrogen adsorption and desorption, SEM and FTIR. Kinetic, isothermal and thermodynamic adsorption studies were carried out. Biochars behaved according to the pseudo-second order (PSO) kinetic model, with similar removal percentages of MB using AB and CB. In contrast, AB showed significantly higher removal percentages of 17β-S than CB. The Sips model agreed to isothermal adsorption data of 17β-S onto all biochars. For MB adsorption, Freundlich model agreed to data using B and AB, and Langmuir model was more suitable for CB. The process was viable, spontaneous, endothermic and showed increase in entropy, except for 17β-S adsorption onto CB. Consequently, the activated and catalytic pyrolysis processes increased the adsorptive potential of biochar derived from 2G lignocellulosic residue. Finally, CB and AB obtained significant removal percentage values of MB (85.8–99.3 %) and 17β-S (37.6–76.7 %), where CB is favorable due to its simpler preparation steps.

Improving the solar ethanol distillation system by combining the heat pipe and parabolic trough collector

This research examines the advantages of utilizing heat pipe technology with parabolic trough collectors in solar ethanol distillation systems. The goal of this work is to optimize the ethanol yield and concentration generated from the distillation of the ethanol–water mixtures from various types of feedstock. Laboratory experiments were conducted to analyze the effect of charged concentrations (2 % to 10 % v/v) and the properties of feedstock (pineapple, sticky rice, and molasses) on the distillation. The results indicate the feedstock types and charged concentration significantly affected the rate of output and ethanol yield. The amount and concentration of distilled ethanol from molasses (385 ml, 70 % v/v) was higher than that of sticky rice (375 ml, 68 % v/v) but highest from pineapple (395 ml, 72 % v/v). Even though pineapple resulted in the highest overall distillated ethanol, pineapple and sticky rice are costly feedstock, as well as increasing complexity in the ethanol production process, which could result in a reduction of value added investments. Implementing renewable solar energy yield ethanol for reduced operating cost or better benefit overall production to underpin a sustainability aspect of agriculture compared to standard conventional distillation. This research contribution to the solar ethanol distilling process, production of biofuels, and interest in renewable fuel sources.

Environmental impact and energy balance assessment in ethanol production from sugarcane molasses: A life cycle analysis in southern India

Blending ethanol with fossil fuels is regarded as an important measure to reduce overall greenhouse gas emissions and the carbon footprint. However, there is a lack of comprehensive studies addressing overall greenhouse gas emissions and energy utilization during ethanol production from sugarcane in South India. This study represents a pioneering attempt to determine the emissions and resource utilization, enabling a comparison of the carbon footprint of the ethanol production process with that of using fossil fuels. The study employed the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model to calculate greenhouse gas emissions and resource utilization. Data was obtained from field studies conducted at Gayatri Sugars Limited, Telangana state, India. The collected data was input into a life cycle analysis (LCA) model in which two cane trash treatment methods were evaluated: burning and mulching. In terms of emissions, the CO2 emissions for one ton of sugarcane were 43.86 kg during cultivation, 45.98 kg during transportation, 69.05 kg during burning of cane trash, and 6.37 kg during the production of one ton of ethanol. The overall energy yield ratio was found to be 15.795 MJ/MJf. Emissions from sugarcane farming and transportation stages were high, significantly contributing to a high carbon footprint. The net emission was significantly lower for the mulching process, which also improved soil characteristics and fertility. The outcomes provide valuable insights for academia, industrial decision-makers, and policymakers at both state and central government levels.

Energy assessment and heat integration of biofuel production from bio-oil produced through fast pyrolysis of sugarcane straw, and its upgrading via hydrotreatment

Sugarcane processing is one of the most important economic activities in Brazil, producing ethanol and sugar for domestic and international markets. Utilising the lignocellulosic residues of this industry, specifically bagasse and straw, would increase the second-generation biofuel production without increasing the sugarcane planted area. Among the processes available, the fast pyrolysis is a thermochemical conversion process that produces mainly bio-oil, a liquid with several advantages over solid biomass, regarding transportation, pumping, storage, and handling. Moreover, the bio-oil can be upgraded to obtain biofuels of higher added-value. Among feasible upgrading technologies, the hydrotreatment is one of the most promising methods for eliminating the reactive functionalities of the bio-oil by removing oxygen or cracking large molecules in the presence of hydrogen; however, this comes at the expense of a significant hydrogen consumption. Thus, the aim of this study is to evaluate the biofuel production through the fast pyrolysis of sugarcane straw, followed by the upgrading of the produced bio-oil via hydrotreatment. The evaluation is carried out by way of energy and mass balances of the processes, performed using the software Aspen Plus. Furthermore, the possibilities of integrating the bio-oil production and upgrading into the conventional ethanol and sugar production process will also be assessed through heat integration, applying the Pinch analysis. Results showed the potential for renewable gasoline and diesel production with yields of 0.086 kg/kg of dry straw and 0.08 kg/kg of dry straw, respectively. Additionally, integrating the pyrolysis process, including the bio-oil upgrading, into the ethanol production process can achieve a liquid fuel production (ethanol, gasoline and diesel) of 2289.8 MJ/t cane, which represents an increase of 29 %, while the surplus electricity increases in 5.3 %, when compared to the conventional ethanol production plant.

Cell Recycling Application in Single-Stage and Sequential-Stage Co-Production of Xylitol and Ethanol Using Corn Cob Hydrolysates

A sustainable bioeconomy in agricultural and agro-industrial production must inevitably involve the sustainable use of agricultural residues through zero-waste processes. Corn cob is considered crucial agricultural waste as 278 and 293 million tons were produced worldwide in 2022 and 2023, respectively. Corn cob hydrolysates, which are abundant in xylose and glucose, could be efficiently utilized for xylitol and ethanol production through the cultivation of recycling the yeast strain Candida magnoliae TISTR 5664 in the single-stage and sequential-stage co-production of these products. The statistically significant maxima (p ≤ 0.05) ethanol concentrations were improved by 7.8% (49.9–51.7 g/L or 91.3–95.6% of the theoretical) from the single stage of ethanol production employing recycled cells and 9.9% (50.9–54.1 g/L or 77.3–83.9% of the theoretical) from the second step of sequential-stage co-production using recycled cells without xylitol accumulation. Conversely, the single-stage xylitol production utilizing recycled cells under microaerobic conditions resulted in a statistically significant lower (p ≤ 0.05) xylitol concentration by two folds relative to the control, while ethanol concentration was elevated by almost double. The statistically significant maximum (p ≤ 0.05) xylitol was achieved at 25.9 g/L (58.6% of the theoretical) when sequential-stage co-production was initiated in the first step with fresh inoculum only and not recycled cells. The sequential-stage co-production of xylitol and ethanol presented the potential for statistically significant improvement (p ≤ 0.05) of both xylitol and ethanol production processes.

Highly Efficient Production of Cellulosic Ethanol from Poplar Using an Optimal C6/C5 Co-Fermentation Strain of Saccharomyces cerevisiae.

Cellulosic ethanol is the key technology to alleviate the pressure of energy supply and climate change. However, the ethanol production process, which is close to industrial production and has a high saccharification rate and ethanol yield, still needs to be developed. This study demonstrates the effective conversion of poplar wood waste into fuel-grade ethanol. By employing a two-step pretreatment using sodium chlorite (SC)-dilute sulfuric acid (DSA), the raw material achieved a sugar conversion rate exceeding 85% of the theoretical value. Under optimized conditions, brewing yeast co-utilizing C6/C5 enabled a yield of 35 g/L ethanol from 10% solid loading delignified poplar hydrolysate. We increased the solid loading to enhance the final ethanol concentration and optimized both the hydrolysis and fermentation stages. With 20% solid loading delignified poplar hydrolysate, the final ethanol concentration reached 60 g/L, a 71.4% increase from the 10% solid loading. Our work incorporates the pretreatment, enzymatic hydrolysis, and fermentation stages to establish a simple, crude poplar waste fuel ethanol process, expanding the range of feedstocks for second-generation fuel ethanol production.

An alternative process for bioethanol production from marine and freshwater algae using yeast for hydrolysis

This research develops a new process for production of bioethanol from marine and freshwater algae based on hydrolysis using yeast rather than the established methods of enzyme and acid hydrolysis. Yeast were isolated and adapted specifically for this process and the effectiveness of this hydrolysis was evaluated. This method was then evaluated within a full ethanol production process involving ozone pretreatment, and both hydrolysis and fermentation using yeast, under different nutrient supplementation regimes. The process effectiveness was evaluated for species of freshwater (Spirogyra hyalina) and marine (Kappaphycus alvarezii) algae. The yeast-based hydrolysis method outperformed acid and enzyme hydrolysis for both species of freshwater and marine algae, with particularly significant results for the freshwater algae. In the whole of process treatment, the yeast-based hydrolysis approach was effective when combined with ozone pretreatment for marine algae, and without any pretreatment for freshwater algae. The highest ethanol yield was achieved through fermentation with a yeast extract supplement present. These results indicate that ozone pretreatment, hydrolysis using yeast, and fermentation with the use of yeast extract as a nutrient are promising methods for economic ethanol production from seawater algae, and for freshwater algae where ozone pretreatment is not required.

Unlocking waste potential: A neural network approach to forecasting sustainable acetaldehyde production from ethanol upcycling in biomass waste gasification

The upcycling of biomass waste gasification process for ethanol and acetaldehyde production has been augmented by integrating secondary and tertiary processes. A simulation model using Aspen Plus, developed from experimental investigations to assess the viability of this proposed system. Furthermore, this model has been utilized to create an Artificial Neural Network (ANN) prediction model. Process sustainability analysis demonstrated an energy efficiency of 64 % while economic viability up to 80 % process efficiency with an Internal Rate of Return (IRR) of 6 % and a payback period of 2107 days. An optimization strategy and an artificial neural network (ANN)-based predictive model have been developed. Optimization results revealed that a gasifier temperature of around 600 °C, a gasifying agent ratio of 2.0, and an acetaldehyde reactor temperature of 300 °C yield better process outcomes and revenue. The ANN model exhibited robust performance with coefficient of determination (R2) values ranging from 0.92 to 0.98 for acetaldehyde, hydrogen, and total revenue. Mean absolute error (MAE) and mean absolute percentage error (MAPE) fell within the range of 0.03–0.1 and 0.1–1.12 %, respectively. Consequently, given the favorable sustainability and predictive model performance, this study can be used for similar endeavors.

Influence of feedstock selection on cellulosic ethanol production based on densified biomass with calcium hydroxide and regular steam pretreatment

Feedstock selection is a key factor affecting the process of cellulosic ethanol production. Densifying lignocellulosic biomass with chemicals (calcium hydroxide) followed by regular steam autoclave (DLCA(ch)) is an emerging and efficient pretreatment technology. In this study, different crop straws were selected as feedstock in a DLCA(ch) based process for cellulosic ethanol production, and their experimental and economic performances were evaluated. Both single crop straws and mixed crop straws were used and compared as feedstock for DLCA(ch) based biorefinery. Among single crop straws of corn stover, rice straw and wheat straw, wheat straw had the highest ethanol yield and the lowest feedstock cost, with a minimum ethanol selling price of 2.03 $/gal ethanol considering a 10 % internal rate of return and a 2000 tons crop straw per day biorefinery scale. When mixed crop straws were used as the feedstock, both feedstock cost and ethanol production cost were further reduced, and the minimum ethanol selling price was reduced to 2.02 $/gal ethanol. In addition, the use of mixed crop straws has great potential for large scale DLCA(ch) based process for cellulosic ethanol production.

Bioethanol production by immobilized co-culture of Saccharomyces cerevisiae and Scheffersomyces stipitis in a novel continuous 3D printing microbioreactor.

Biorefineries require low-cost production processes, low waste generation and equipment that can be used not only for a single process, but for the manufacture of several products. In this context, in this research a continuous 3D printing microbioreactor coupled to an Arduino-controlled automatic feeding system was developed for the intensification of the ethanol production process from xylose/xylulose (3:1), using a new biocatalyst containing the co-culture of Scheffersomyces stipitis and Saccharomyces cerevisiae (50/50). Initially, batch fermentations of monocultures of S. cerevisiae and S. stipitis and co-culture were carried out. Subsequently, the immobilized co-culture was used as a biocatalyst in continuous fermentations using the developed microreactor. Fermentations carried out in the microbioreactor presented a 2-fold increase in the ethanol concentration and a 3-fold increase in productivity when compared to monocultures. The microbioreactor developed proved to be efficient and can be extended for other bioproducts production. This approach proved to be a promising alternative for the use of the hemicellulose fraction of biomasses without the need to use modified strains.

Study of ethanol vapor explosion and prediction based on chemical kinetics under high temperature and pressure

AbstractThe study of the explosion parameters of ethanol–air mixture at high pressure and temperature is essential for the safe production of ethanol. However, the explosion characteristics of ethanol vapor at various pressures and temperatures are limited. The mechanism at the flammability limits of ethanol has not been clarified, and the corresponding prediction model is also lacking. In this study, chemical kinetics and machine learning are used to study the mechanism of ethanol explosion and build predictive models, respectively. Our findings show that an increase in the initial pressure has a more pronounced influence on the explosion pressure (Pex) and pressure rise rate (dp/dt) than an increase of temperature. The variation trend of the upper flammability limit (UFL) of ethanol is related to the different effects of temperature and pressure on OH radicals. H + O2<>OH + O and HO2 + CH3<>OH + CH3O had the greatest effect on the generation of OH radicals. The quantitative relationship between the H, O, and OH radicals and UFL was constructed by machine learning, providing a new research perspective for the prediction of the UFL of an inflammable fuel under different pressures and temperatures. The results of the study will provide theoretical and practical guidance for the prevention and control of explosions in the ethanol production process.

Bio-Ethanol Production from Wheat Straw Using Yeast Isolates

In the first hand, the cost of fossil fuel is increasing alarmingly. On the second hand, combustion of fossil fuels contributes for global warming. Therefore, it need to strength the production of renewable energies. The aim of this study was to produce bioethanol from wheat straw using yeast isolates. The isolates were isolated from decomposed soil, termite soil and rotten wood samples using yeast extract peptone dextrose media (YPD) and characterized chemically and morphologically. The wheat straws were powdered and hydrolyzed with dilute sulfuric acids. After neutralization, it was used to produce ethanol. Response surface methodology was employed to optimize the ethanol production process from wheat straws. The isolates were grown optimally at a temperature of 30oC, pH nearly 5, and sugar concentration 70 to 120 g/L. Among hydrolysis conditions, lower acid concentration (less than 1.5%) and temperature of 60oC resulted higher reducing sugars. The optimization study showed that the highest bio-ethanol concentration of 6.8g/l was observed by SWX under the optimum conditions of with 1% H2S04, 60oC temperature and 52.5-minute time hydrolysis at 30°C for 48 hour incubation time. Wheat straws could be good candidate for ethanol production.

Transformations of bamboo into bioethanol through biorefinery.

The increasing demand for energy has prompted scholars to research alternative energy sources. Bamboo is a species of woody perennial grass that belongs to the Gramineae family and the Bambuseae subfamily. It could be considered a possible lignocellulosic substrate for the production of bioethanol due to its favourable environmental effects and increased yearly biomass yield. Non-renewable fossil fuels cannot provide enough energy to meet the needs of contemporary societies. Among the various alternative energy sources, bioethanol has drawn a lot of attention from people all around the world. This paper reviews the cost and process parameters for the synthesis of bioethanol from bamboo. This review aims to increase the effectiveness of the entire ethanol production process by focusing on pretreatment, enzymatic hydrolysis, and fermentation. The emphasis of this review is on the efficient process for producing bioethanol while maintaining environmental sustainability. When compared to other NaOH pretreatment techniques, bamboo substrates prepared with NaOH and ultra-high-pressure explosion (UHPE) exhibit higher enzymatic hydrolyzability when processed under optimal conditions, such as 100MPa, 121°C, and 70rpm for 2h, yielding 89.7-95.1% ethanol after 24h. The article lists the bamboo species responsible for creating each product, making it straightforward for producers to study and select the species based on whatever value-added product they wish to produce bioethanol with different parameters.

The impact of lignocellulosic ethanol production on the environment from a life cycle perspective

In the production process of cellulosic ethanol, all sections are closely related. It is difficult to study its producing law and key factors that affect the process only by experimental means. Computer simulation has a powerful data mining ability, which can analyze, design, and evaluate the production process of cellulosic ethanol. Specifically, it can use data calculated by Aspen Plus before, and analyze the impact of cellulose ethanol production on the environment by life cycle assessment (LCA). Results show that the total environmental impact value of the whole process is 0.20∼0.37 person·a/t. And in the whole process, the growth stage and the production stage have the biggest impact.

From Saccharomyces cerevisiae to Ethanol: Unlocking the Power of Evolutionary Engineering in Metabolic Engineering Applications.

Increased human population and the rapid decline of fossil fuels resulted in a global tendency to look for alternative fuel sources. Environmental concerns about fossil fuel combustion led to a sharp move towards renewable and environmentally friendly biofuels. Ethanol has been the primary fossil fuel alternative due to its low carbon emission rates, high octane content and comparatively facile microbial production processes. In parallel to the increased use of bioethanol in various fields such as transportation, heating and power generation, improvements in ethanol production processes turned out to be a global hot topic. Ethanol is by far the leading yeast output amongst a broad spectrum of bio-based industries. Thus, as a well-known platform microorganism and native ethanol producer, baker's yeast Saccharomyces cerevisiae has been the primary subject of interest for both academic and industrial perspectives in terms of enhanced ethanol production processes. Metabolic engineering strategies have been primarily adopted for direct manipulation of genes of interest responsible in mainstreams of ethanol metabolism. To overcome limitations of rational metabolic engineering, an alternative bottom-up strategy called inverse metabolic engineering has been widely used. In this context, evolutionary engineering, also known as adaptive laboratory evolution (ALE), which is based on random mutagenesis and systematic selection, is a powerful strategy to improve bioethanol production of S. cerevisiae. In this review, we focus on key examples of metabolic and evolutionary engineering for improved first- and second-generation S. cerevisiae bioethanol production processes. We delve into the current state of the field and show that metabolic and evolutionary engineering strategies are intertwined and many metabolically engineered strains for bioethanol production can be further improved by powerful evolutionary engineering strategies. We also discuss potential future directions that involve recent advancements in directed genome evolution, including CRISPR-Cas9 technology.

Selection and improvement of Saccharomyces cerevisiae by direct and mass mating for integrated first and second generation (1G + 2G) ethanol production

The integrated 1G + 2G ethanol production process seems to be a feasible strategy considering the Brazilian scenario, in which sugarcane molasses and bagasse are available substrates in biorefineries. However, such process imposes harsh conditions to yeasts, which must be able to simultaneously deal with several stresses from molasses and hydrolysate. In this work, improved hybrid strains of Saccharomyces cerevisiae with higher resistance for an integrated 1G + 2G ethanol production were obtained by hybridization technique. Initially, 663 wild S. cerevisiae strains were screened in microculture growth assays. Seven strains were pre-selected out of 40 based on their stress multi-tolerance traits. Subsequently, these pre-selected strains underwent evaluation in cell-recycling fed-batch fermentation conditions utilizing a medium containing molasses-bagasse hydrolysate. The two most successful strains from this evaluation were subjected to sporulation, yielding haploid cells. These haploid cells were then subjected to crossbreeding, employing direct and mass mating techniques. From the initial pool of 7 pre-selected strains, 3 hybrid strains were selected due to their enhanced resistance under the demanding conditions of cell recycling fed-batch fermentation, particularly when utilizing a higher osmotic molasses-hydrolysate medium. These hybrid strains consistently exhibited high cell viability rates and effectively accumulated elevated levels of trehalose and glycogen over the course of five fermentation cycles. Remarkably, they maintained ethanol productivity at levels comparable to their respective parental strains. The genotyping molecular identification attested the difference between the hybrids and the parental strains. The 3 hybrids selected seem to present valuable backgrounds for metabolic engineering for lignocellulosic-derived xylose fermentation.

Effect of raw material structural composition on the fermentation process of ethanol production

Ethanol is becoming the important renewable energy sources in the world which produces from carbohydrate resources. The raw material selection is the important procedure for real industrial production. The effect of biomass structural composition in feedstock on ethanol production is therefore needed to explore for feedstock selection. According to the previous research studies, the fermentation process includes pre-treatment and fermentation of sugar to ethanol. This study focuses on the simulation of raw material variation in ethanol production especially the structural composition of carbohydrate that contains three main components, cellulose, xylan, and lignin, in the fermentation section. The simulation model is validated by the data of previous study information with small deviation. The mixture design method is used for result interpretation and analysis. From the design of experiment, there are 14 scenarios and the selected response parameter is the mass fraction of ethanol in outlet stream of fermentation section. From the results, the maximum mass fraction of ethanol in outlet stream is in the scenario which has a large amount of cellulose and xylan fractions. This is because the conversion of reaction in the fermentation reactor mostly consumes cellulose and xylan to produce glucose and xylose, respectively, and converts them into ethanol product. From the overall result of this study, the important of raw material selection in ethanol production is illustrated.

Energy and nitrogen utilization of lactating dairy cattle fed increasing inclusion of a high-protein processed corn coproduct*

Advancing technologies of the corn dry-milling ethanol production process includes the mechanical separation of fiber-containing particles from a portion of plant- and yeast-based nitrogenous particles. The resulting high-protein processed corn coproduct (HPCoP) contains approximately 52% crude protein (CP), 36% neutral detergent fiber (NDF), 6.4% total fatty acids (TFA). The objective of this experiment was to examine the effects of replacing nonenzymatically browned soybean meal with the HPCoP on dry matter intake (DMI), energy and N utilization, and milk production of lactating Jersey cows. Twelve multiparous Jersey cows were used in a triplicated 4 × 4 Latin square design consisting of four 28-d periods. Cows were blocked by milk yield and assigned randomly to 1 of 4 treatment diets that contained HPCoP (dry matter [DM] basis) at (1) 0%; (2) 2.6%; (3) 5.4%; and (4) 8.0%. Diets were formulated to be isonitrogenous and thus replace nonenzymatically browned soybean meal with HPCoP in the concentrate mix, while forage inclusion remained the same across diets. Increasing the concentration of HPCoP had no effect on DMI (mean ± SE; 19.9 ± 0.62 kg/d), but tended to linearly increase milk yield (27.8, 28.5, 29.8, and 29.0 ± 1.00 kg/d). Although no difference was observed in the concentration of milk protein with increasing inclusion of HPCoP (3.40% ± 0.057%), the concentration of fat linearly increased with the inclusion of HPCoP (5.05%, 5.19%, 5.15%, 5.47% ± 0.18%). No differences were observed in the digestibility of DM, NDF, CP, TFA, and gross energy averaging 66.6% ± 0.68%, 49.0% ± 1.03%, 66.1% ± 0.82%, 73.6% ± 1.73%, 66.3% ± 0.72%, respectively, with increasing HPCoP inclusion. The concentration of dietary gross energy linearly increased with increasing concentrations of HPCoP (4.25, 4.26, 4.28, and 4.31 ± 0.01 Mcal/kg), but no difference was observed in digestible energy and metabolizable energy (ME) across treatments averaging 2.83 ± 0.033 and 2.53 ± 0.043 Mcal/kg, respectively. Concentration of dietary net energy for lactation (NEL) tended to increase with increasing HPCoP (1.61, 1.72, 1.74, 1.72 ± 0.054 Mcal/kg) with the ratio of NEL:ME increasing linearly with increasing HPCoP inclusion (0.648, 0.676, 0.687, 0.677 ± 0.0124). Results of this study suggest that inclusion of the HPCoP can replace nonenzymatically browned soybean meal and support normal milk production.

Al2(SO4)3 alters the antioxidant mitochondrial metabolism of Botritys cinerea and optimizes the production of cellulose and oxidative degrading enzymes

The enzymes produced by pathogenic fungi, especially Botritys cinerea, deserve specific attention due to the diversity of their applications, mainly in biofuel production, food processing, and the pharmaceutical industry. Thus, this work used Al2(SO4)3 as a stressor in order to evaluate if the stress levels caused by the concentrations of 100, 250, 500, and 1000 ppm were sufficient to increase the production of hydrolytic cellulolytic enzymes (FPase, CMCase, Avicelase, β-glucosidase, xylanase) and oxidative (laccase and manganese peroxidase). The study also evaluated the stress levels in previously treated mycelia of B. cinerea and whether they corresponded to the different states of mitochondrial respiration. Our study indicates that Al2(SO4)3 increased the production of cellulolytic and oxidative enzymes in all concentrations in a dose-dependent manner and that Al2(SO4)3 alters the mitochondrial respiratory rate, with lower ATP productions, indicating that less-coupled mitochondria were obtained and that this may be due to the increase of oxidative stress. Thus, it is plausible to suggest the use of Al2(SO4)3 in the production of cellulolytic enzymes, which could be used in the hydrolysis stage of second-generation ethanol production processes, as it reduces the time required for enzymatic expression applications in industrial processes.