High Ethanol Concentrations Research Articles

Effect of Alkali Source on Crystal Regulation and Ethanol Gas Sensing Properties of Nano-ZnO

This study investigates the ethanol gas-sensing mechanisms of ZnO nanocrystals with distinct morphologies, synthesized via a hydrothermal method using various alkali sources. Significant differences in the gas-sensing performance and morphology of ZnO samples synthesized with ammonium carbonate (Na2CO3), hexamethylenetetramine (HMTA), ammonia solution (NH3·H2O), and sodium hydroxide (NaOH) were observed. ZnO were confirmed to be impurity-free through XRD analysis, and their morphological features were characterized by SEM. TEM, XPS, and FTIR were employed to further analyze the crystal structure and binding energy of ZnO. To elucidate the underlying mechanisms, density functional theory (DFT) calculations combined with electron depletion layer theory were applied to assess charge transfer processes and identify the most sensitive ZnO crystal planes for ethanol detection. Experimental gas-sensing tests, conducted across 5–1000 ppm ethanol concentrations within a 150–350 °C range, showed that ZnO prepared with Na2CO3, HMTA, and NaOH was responsive at high ethanol concentrations as low as 100 °C, while ZnO synthesized with ammonia required 250 °C to exhibit sensitivity. All ZnO samples demonstrated excellent recovery at low concentrations at 250 °C. By integrating experimental findings with theoretical insights, this study provides a comprehensive understanding of ethanol gas-sensing mechanisms in ZnO, highlighting the role of crystal plane engineering and charge transfer dynamics as critical factors influencing gas response.

Impacts of maternal separation stress on ethanol intake and endocannabinoid system in adolescent mice

Clinical and preclinical studies suggest that early-life stress can increase the risk of developing ethanol use disorder later in life. Although the endocannabinoid (eCB) system plays a role in stress-related behaviors and ethanol consumption, it remains unclear whether the eCB system is affected in response to a combination of both factors. By using male and female adolescent C57BL/6J mice subjected to a maternal separation (MS) stress paradigm from postnatal day (PND) 1 to 14, we explored (1) the consequences of early-life stress experiences on ethanol consumption in adolescent mice and (2) how these events affect the eCB system and neuronal activation in brain regions associated with the reward system. In Experiment 1, we found that MS increased involuntary ethanol consumption specifically during the first exposure to the drug (during a 24 h-long trial on PND 28) and decreased the active/inactive nose poke ratio (discrimination index) specifically when mice were subjected to 1 h-sessions (PND 82–86) in an operant ethanol self-administration paradigm. In Experiment 2, during a two-bottle free choice paradigm, we found that MS increased mice preference for high ethanol concentrations (15 % and 20 %) but not lower ethanol concentrations (5 % and 10 %). Except for Mgll gene expression in the dorsal striatum (DS) in Experiment 2, no statistically significant effects of MS were observed regarding neuronal activation on the prefrontal cortex, DS, globus pallidus, and substantia nigra following a binge operant ethanol self-administration session (Experiment 1) or the eCB system molecules (Cnr1 and Faah gene expression) in the DS (Experiment 2).

Physicochemical Properties and Biological Activities of Polysaccharides from Panax Notoginseng Separated by Fractional Precipitation.

The dried root of Panax notoginseng is a medicinal and food ingredient. P. notoginseng polysaccharides (PNPs) have physicochemical properties, which have not been fully elucidated. This study aimed to identify a method to separate the PNP fractions and investigate their activities. PNPs were prepared from roots by hot water extraction, deproteinization, and decolorization. PNP20, PNP40, and PNP60 fractions were isolated through stepwise ethanol precipitation at 20 %, 40 %, and 60 % concentrations, respectively. The three polysaccharide fractions were characterized using chromatography, spectroscopy, and thermogravimetric analysis, and their moisture retention, antioxidant, and tyrosinase-inhibition properties were evaluated. Monosaccharide composition analysis showed that the three PNPs contained mannose (Man), galacturonic acid (GalA), glucose (Glc), galactose (Gal), and arabinose (Ara) in different molar ratios. HPGPC analysis demonstrated that the polysaccharides precipitated with higher ethanol concentrations had lower molecular weights (Mw). Furthermore, all PNPs had distinct moisturizing and hygroscopic properties and antioxidant activities, with PNP60 showing better antioxidant properties and a competitive mixture of hygroscopic properties and tyrosinase inhibition. The chemical composition and structural characteristics of PNPs could affect their functional attributes. PNP60 has the potential to be a moisturizer and antioxidant and could be used in the development of cosmetic ingredients.

Clostridia as Promising Biofactory for Heterotrophic (Fructose) and Autotrophic (C1-Gas) Fermentation

This study compared the performance of Clostridium ljungdahlii and Clostridium aceticum in the fermentation of fructose and C1-gasses (CO, CO2, N2) to produce valuable products such as ethanol and acetic acid. In heterotrophic fermentation (fructose), C. ljungdahlii yielded high ethanol concentrations (350 mg/L) and acetic acid (500 mg/L), with optimal production at pH 8 on the first day of fermentation. Although autotrophic fermentation (C1-gasses) resulted in lower ethanol levels (200 mg/L), it remained a viable option. Conversely, C. aceticum predominantly produced acetic acid in both fermentation modes, with higher concentrations in the heterotrophic fermentation (1600 mg/L) than the autotrophic fermentation (380 mg/L). These findings demonstrate the versatility of both microorganisms for producing valuable metabolites. C. ljungdahlii shows promise for bioethanol production, while C. aceticum excels at generating acetic acid, a crucial component in bioplastics and various industrial processes.

Liposomes and Ethosomes: Comparative Potential in Enhancing Skin Permeability for Therapeutic and Cosmetic Applications

Skin diseases are a common health problem affecting millions of people worldwide. Effective treatment often depends on the precise delivery of drugs to the affected areas. One promising approach is currently the transdermal drug delivery system (TDDS), whose significant challenge is the poor penetration of many compounds into the skin due to the stratum corneum (SC), which acts as a formidable barrier. To overcome this limitation, nanocarriers have emerged as a highly effective alternative. This review discusses the use of liposomes and ethosomes for transdermal drug delivery. Liposomes are micro- or nanostructures consisting of a lipid bilayer surrounding an aqueous core. They facilitate transdermal drug penetration and may be advantageous for site-specific targeting. Some methods of treating skin diseases involve incorporating drugs such as acyclovir, dithranol, and tretinoin or bioactive compounds such as fluconazole, melanin, glycolic acid, kojic acid, and CoQ10 into nanocarriers. The inability of liposomes to pass through the narrowed intercellular channels of the stratum corneum led to the invention of lipid-based vesicular systems such as ethosomes. They are structurally similar to conventional liposomes, as they are prepared from phospholipids, but they contain a high ethanol concentration. Ethosomes are noninvasive carriers that allow drugs to reach the deep layers of the skin. Examples of commonly used substances and drugs combined with ethosomes in cosmetics include methotrexate, ascorbic acid, vitamin A and E, and colchicine. A significant development in this area is the use of rutin-loaded ethosomes. Encapsulating rutin in ethosomes significantly improves its stability and enhances skin penetration, allowing more efficient delivery to deeper skin layers. In cosmetics, rutin–ethosome formulations are used to protect the skin from oxidative stress, reduce redness, and improve capillary strength, making it a valuable formulation in anti-aging and anti-inflammatory products. The results of the first clinical trial of the acyclovir–ethosome formulation confirm that ethosomes require further investigation. The work provides an update on recent advances in pharmaceutical and cosmetic applications, mentioning the essential points of commercially available formulations, clinical trials, and patents in the recent past.

Unveiling genetic anchors in saccharomyces cerevisiae: QTL mapping identifies IRA2 as a key player in ethanol tolerance and beyond.

Ethanol stress in Saccharomyces cerevisiae is a well-studied phenomenon, but pinpointing specific genes or polymorphisms governing ethanol tolerance remains a subject of ongoing debate. Naturally found in sugar-rich environments, this yeast has evolved to withstand high ethanol concentrations, primarily produced during fermentation in the presence of suitable oxygen or sugar levels. Originally a defense mechanism against competing microorganisms, yeast-produced ethanol is now a cornerstone of brewing and bioethanol industries, where customized yeasts require high ethanol resistance for economic viability. However, yeast strains exhibit varying degrees of ethanol tolerance, ranging from 8 to 20%, making the genetic architecture of this trait complex and challenging to decipher. In this study, we introduce a novel QTL mapping pipeline to investigate the genetic markers underlying ethanol tolerance in an industrial bioethanol S. cerevisiae strain. By calculating missense mutation frequency in an allele located in a prominent QTL region within a population of 1011 S. cerevisiae strains, we uncovered rare occurrences in gene IRA2. Following molecular validation, we confirmed the significant contribution of this gene to ethanol tolerance, particularly in concentrations exceeding 12% of ethanol. IRA2 pivotal role in stress tolerance due to its participation in the Ras-cAMP pathway was further supported by its involvement in other tolerance responses, including thermotolerance, low pH tolerance, and resistance to acetic acid. Understanding the genetic basis of ethanol stress in S. cerevisiae holds promise for developing robust yeast strains tailored for industrial applications.

Pressurized Liquid Extraction of Antioxidant and α-Amylase-Inhibitory Compounds from Red Seaweed Using Water-Ethanol Mixtures.

Red seaweeds from the coastal shores of Ilo (Peru) are a natural source of high-value compounds beneficial to health due to their high antioxidant capacity. Thus, this work evaluated the effect of water-ethanol mixtures (0, 15, and 30%; v/v) at high temperatures (90, 120, and 150 °C) on the polyphenol content, antioxidant capacity, and polyphenols profile of red seaweed (Chondracanthus chamissoi) during a pressurized liquid extraction process, whose parameters were set at 10 atm, with a single cycle of extraction and a volume of 150%. An increase in temperature and ethanol had a positive effect on antioxidant compounds. Thus, the best processing conditions were established at 150 °C and 30% ethanol, allowing for the extraction of a high polyphenol content (2.04 mg GAE/g dw) and antioxidant capacity (IC50: 7.46 mg/mL, ORAC: 148.98 μmol TE/g dw). High ethanol concentrations (30%) effectively recovered phenolic acids, flavonols, and phlorotannins for the polyphenols profile. However, the use of pure water was more effective in recovering flavonols. Interestingly, using pure water as an extraction solvent at high temperatures allowed for a more significant inhibition of the α-amylase enzyme than water-ethanol mixtures under the same conditions. Finally, the results can be utilized for future industrial scaling and the potential utilization of extracts in developing diabetes treatments.

Dynamic changes in microbial communities and volatile compounds in kombucha fermentation using Flos sophorae and Elm fruits, compared to black and green tea

The dynamic changes in physicochemical properties, microbial communities, and volatile compounds in kombucha made from Flos sophorae (FLSK) and Elm fruit (EFK) were compared to those of black tea (BTK) and green tea (GTK) over a 12-day fermentation period. The results revealed that overall flavonoid and polyphenol content, as well as antioxidant activity, increased initially and then decreased, accompanied by a steady reduction in pH within the fermentation broths investigated. Notably, the GTK exhibited stronger antioxidant activity than the other fermentation broths. Furthermore, 16S rRNA gene sequencing revealed that Komagataeibacter rhaeticus, Komagataeibacter saccharivorans, and Acidovorax wautersii were the dominating microbial species in the fermentation broths under this study. Komagataeibacter rhaeticus initially reduced and then increased throughout the FLSK fermentation, whereas Komagataeibacter saccharivorans increased from day 0 to day 6, and remain stable by day 12 during the EFK fermentation. Comparative analysis revealed that Komagataeibacter rhaeticus was more abundant in the FLSK and GTK than in the EFK and BTK, whereas Komagataeibacter saccharivorans showed a higher abundance in the EFK relative to the other fermentation broths. Gas chromatography-mass spectrometry identified acetic acid, linalool, ethanol, and ethyl acetate as the major volatile chemicals that rose significantly in fermentation mixtures of the examined substrates. The FLSK had a much higher linalool concentration than the other fermentation broths, although the EFK and GTK had higher ethanol content. Correlation study found that Komagataeibacter rhaeticus was negatively related with alcohol compounds, but Komagataeibacter saccharivorans was positively associated with a diverse spectrum of acids, alcohols, and esters. The study found changes in bioactive chemicals as well as interactions between bacterial populations and volatile compounds throughout fermentation in the substrates investigated.

Tolerance and efficient metabolization of extremely high ethanol concentrations by a social wasp

Ethanol, a natural by-product of sugar fermentation, can be found in various fruits and nectar. Although many animals routinely consume ethanol in low concentrations as part of their natural diets, its inherent toxicity can cause severe damage. Even species particularly well adapted to ethanol consumption face detrimental effects when exposed to concentrations above 4%. Here, we investigated the metabolism of ethanol and its impact on survival and behavior in the Oriental hornet (Vespa orientalis), a social wasp that naturally consumes ethanol. We show that chronic ethanol consumption, even at concentrations as high as 80%, had no impact on hornet mortality, construction behavior, or agonistic behavior. Using 13C1 labeled ethanol, we show that hornets efficiently metabolized ingested ethanol and at a much higher rate than honey bees. The presence of multiple copies of the alcohol dehydrogenase (NADP+) gene in the Vespa genera suggests a potential mechanism for ethanol tolerance. These findings support the hypothesis that the mutualistic relationship between ethanol-producing organisms and vespid hosts may be at the origin of their remarkable capacity to utilize and metabolize ethanol.

Development of an Effective Sterilization Protocol for Plant Tissue Culture Studies in Superfruit Aronia [Aronia melanocarpa (Michaux) Elliot

Effective sterilization protocols are crucial for a successful tissue culture study in Aronia. These protocols directly influence contamination rates, shoot health, and root development. In this context, the aim of the study is to develop an effective sterilization protocol for plant tissue culture studies in Aronia [Aronia melanocarpa (Michaux) Elliot], commonly known as the "superfruit." In study, shoot tips of the Nero Aronia variety were used as material. The sterilized shoot tips were transferred to the respective plant tissue culture media in a randomized parcels trial pattern with three replicates, each containing three explants per replicate. Various concentrations and combinations of sterilizing agents, such as sodium hypochlorite (NaOCl), hydrogen peroxide (H2O2), mercuric chloride (HgCl2), and ethanol (C2H5OH), were evaluated to determine their effectiveness in maintaining tissue health and reducing contamination. A total of twelve protocols were developed, incorporating different concentrations of these chemicals. The results showed that the combination of 5% NaOCl and 3% H2O2 provided the lowest average contamination rate (5%) and the highest average number of healthy (uncontaminated) explants (9.00 piece), demonstrating the sterilization efficiency of this combination. On the other hand, protocols containing HgCl2, especially at higher concentrations, resulted in impaired root development. High ethanol concentrations also contributed to effective sterilization, with the combination of 7% NaOCl and 80% ethanol yielding a low contamination rate (8%) and preserving tissue health. This study emphasizes the need to balance sterilization protocols between effective contamination control and tissue viability. The findings are expected to benefit the improvement and development of tissue culture techniques for Aronia and similar species, providing a basis for further research on effective sterilization practices, which are currently limited in Aronia tissue culture.

Enhanced bioethanol production from cassava waste: optimization of thermochemical pretreatment for maximum sugar recovery and characterisation of potential fractions

ABSTRACT Thermochemical pretreatment is an interesting approach for the effective separation of lignocellulosic biomass before fermentation for bioethanol production. This research focused on optimising the thermochemical pretreatment conditions of cassava waste using response surface methodology to predict the glucose yields under the optimal condition. The optimised conditions of 0.045 M of NaOH concentration at 153.59 °C for 48.03 min resulted in the maximum glucose yield of 93.87%. In addition, fermentation process can generate ethanol within a range of solid loading from 10% to 20%. The highest concentration of ethanol was 34.53 ± 0.56 g/L after 72 h, equivalent to ethanol yield of 0.46 g/g. The co-products were also characterised for further utilisation in biorefinery concept. The results of this study confirmed that the thermochemical pretreatment process using the NaOH catalyst could provide high glucose yields, which can be easily converted into bio-based fuels and further valorised of co-products to value-added chemicals.

Ethosomes-mediated tryptanthrin delivery as efficient anti-psoriatic nanotherapy by enhancing topical drug absorption and lipid homeostasis

Psoriasis is a chronic, relapsing, and refractory immune-mediated skin disease with the etiology and pharmaceutical targets remaining unsatisfactorily addressed. Topical herbal-derived compounds, such as tryptanthrin (Tryp), have been considered as an alternative therapy for psoriasis due to their lower costs and fewer side effects compared to other therapies. However, the effectiveness of topically administered drugs is substantially limited by the thickened pathological skin barrier and the low bioavailability of drugs in the deeper layers of the lesion. Ethosomes, being a novel phospholipid-based vesicle system with high content of ethanol, have been implicated in enhancing topical drug absorption and restoring psoriatic lesions. In this study, taking advantages of ethosomes as a soft and malleable drug carrier, we constructed the Tryp-loaded ethosome (Tryp-ES) through a one-step microfluidics-based technique. The optimal formulation of Tryp-ES was achieved by adding amino-acid-derived surfactant sodium lauroyl glutamate, and Tryp-ES exhibited homogeneous particle size and favorable stability at room temperature. In vitro evaluations showed that Tryp of Tryp-ES could be easily internalized into cells and accumulated in cell nuclei, hence inhibited the abnormally proliferated keratinocytes by inducing apoptosis. In vivo and in vitro assessment using psoritic skin of mice revealed that Tryp-ES had preferred skin retention and permeation of loaded drugs within the initial 1 h of topical administration, which could be attributed to transient disintegrations of cell membranes by ethosomes, thus improved cellular fluidity and permeability. Notably, a synergistic effect of ethosomes and Tryp was found in psoriatic mice. Tryp-ES-treated mice showed substantially ameliorated symptoms of psoriasis and reduced pathological alterations due to hyperplasia, inflammation and angiogenesis, without detectable local or systemic toxicities. Interestingly, lipidomics analysis confirmed that the supplementation of phospholipids, as in the form of ethosome vehicles, was an alterantive strategy to relieve psoriatic pathologies. Taken together, this study provides a novel impact for ethosomal topical delivery of Tryp and underlines their potential as an effective therapy for the management of psoriasis.

Saccharomyces cerevisiae for lignocellulosic ethanol production: a look at key attributes and genome shuffling.

These days, bioethanol research is looking at using non-edible plant materials, called lignocellulosic feedstocks, because they are cheap, plentiful, and renewable. However, these materials are complex and require pretreatment to release fermentable sugars. Saccharomyces cerevisiae, the industrial workhorse for bioethanol production, thrives in sugary environments and can handle high levels of ethanol. However, during lignocellulose fermentation, S. cerevisiae faces challenges like high sugar and ethanol concentrations, elevated temperatures, and even some toxic substances present in the pretreated feedstocks. Also, S. cerevisiae struggles to efficiently convert all the sugars (hexose and pentose) present in lignocellulosic hydrolysates. That's why scientists are exploring the natural variations within Saccharomyces strains and even figuring out ways to improve them. This review highlights why Saccharomyces cerevisiae remains a crucial player for large-scale bioethanol production from lignocellulose and discusses the potential of genome shuffling to create even more efficient yeast strains.

Conversion of glycerol into value-added products

Biomass residues and industrial waste are of great interest for their potential to produce a wide range of bioenergy and value-added products. Crude glycerol can be valorized into value added products by several microorganisms through microbial fermentation. Thus, Significant efforts have been made to develop biological methods to convert crude glycerol into various valuable chemicals and fuels, including 1, 3-propanediol, hydrogen and ethanol.In this context, our work have use glycerol medium as source of carbon for investigate bioethanol and 1, 3-propandiol production, using a microbial consortium. All experiments was carried out in sealed bottles, the reaction medium is placed in the shaker incubator at 37°C with stirring at 130 rpm. . Nitrogen gas was injected to create anaerobic conditions. The highest concentration of ethanol and 1,3 – propanediol obtained were 3.47 (g/l) and 4.8 mg/l respectively . These results highlight promising avenues for the valorization of biomass residues and industrial wastes in sustainable bioenergy production.

Emerging Nanotechnology Involved in Skin Cancer: Pathogenesis, Biomarkers, Ethosomal Formulation and Future Perspective.

Skin cancer, which comprises both melanoma and non-melanoma forms, is frequently diagnosed as the predominant malignancy among today's population. Existing treatments are often prolonged and complex, have a low rate of success, and have side effects. This complexity leads to poor patient adherence and increases the risk of disease recurrence. Ethosomes, extensively studied for their applications in topical and transdermal therapies, are distinguished by their high ethanol content, which facilitates enhanced skin penetration and efficient drug delivery. Compared to traditional liposomes, ethosomes offer notable advantages due to their unique composition, demonstrating potential efficacy in treating various skin conditions, including basal cell carcinoma, squamous cell carcinoma, and melanoma. The present review provides a brief introduction to skin melanoma and its pathogenesis, signalling pathways, biomarkers, the need for ethogel-based drug delivery, applications of ethosomes against skin cancer, and clinical trials.

Exploring lipids: A comprehensive review on their utilization in the formulation of liposomes, phytosomes, and ethosomes for advanced drug delivery systems"

This comprehensive review explores the diverse applications of lipids in the formulation of advanced drug delivery systems, specifically focusing on liposomes, phytosomes, and ethosomes. Lipids, crucial components in these formulations, play a pivotal role in enhancing drug solubility, stability, and bioavailability. The review systematically examines the latest advancements in lipid-based delivery systems, shedding light on their unique characteristics and applications. In the realm of liposomes, the study delves into various lipid compositions, highlighting their influence on liposomal structure and function. Additionally, the review explores the integration of phytosomes, which involve the complexation of drugs with plant-derived phospholipids, showcasing their potential to improve therapeutic efficacy. Ethosomes, lipid vesicles containing high concentrations of ethanol, are also extensively discussed, emphasizing their ability to enhance transdermal drug delivery. Critical analyses of recent research findings, including the impact of lipid selection on vesicle stability, drug release kinetics, and pharmacokinetics, are presented. The review further examines the challenges associated with lipid-based formulations, providing insights into potential avenues for future research and development. By synthesizing current knowledge, this review serves as a valuable resource for researchers, clinicians, and pharmaceutical scientists seeking a comprehensive understanding of the role of lipids in optimizing liposomal, phytosomal, and ethosomal drug delivery systems.

Simultaneous improvement of fructophilicity and ethanol tolerance of Saccharomyces cerevisiae strains through a single Adaptive Laboratory Evolution Strategy

Saccharomyces cerevisiae is the main yeast used in the winemaking industry. Its innate glucophilicity provokes a discrepancy in glucose and fructose consumption during alcoholic fermentation of grape must, which, combined with the inhibitory effect of ethanol accumulated in the fermentation broth, might lead to stuck or sluggish fermentations. In the present study, we realized an Adaptive Laboratory Evolution strategy, where an alcoholic fermentation of a 20 g/L fructose broth was followed by cell selection in a high ethanol concentration environment, employed in two different S. cerevisiae strains named CFB and BLR. The evolved populations originated from each strain after 100 generations of evolution exhibited diverse fermentative abilities. One evolved population, originated from CFB strain, fermented a synthetic broth of 100 g/L glucose and 100 g/L fructose to dryness in 170 h, whereas the parental strain did not complete the fermentation even after 1000 h of incubation. The parameters of growth of the parental and evolved populations of the present study, as well as of the ethanol tolerant populations acquired in a previous study, when grown in a synthetic broth of 100 g/L glucose and 100 g/L fructose, were calculated through a kinetic model, and were compared to each other in order to identify the effect of evolution on the biochemical behavior of the strains. Finally, in a 200 g/L fructose synthetic broth fermentation, only the evolved population derived from CFB strain showed improved fermentative behavior than its parental strain.

From tyrosine to hydroxytyrosol: a pathway involving biologically active compounds and their determination in wines by ultra performance liquid chromatography with mass spectrometry.

Hydroxytyrosol (HT) is a bioactive compound present in a limited number of foods such as wines, olives, and olive oils. During alcoholic fermentation, yeast converts aromatic amino acids into higher alcohols such as tyrosol, which can undergo hydroxylation into HT. The aim of this study was to validate an analytical method using ultra performance liquid chromatography coupled with mass spectrometry (UPLC/MS-MS) to quantify HT and its precursors (tyrosine, hydroxyphenylpyruvic acid, hydroxyphenylacetaldehyde, 4-hydroxyphenylacetic acid, and tyrosol) in wines. Their occurrence was evaluated in a total of 108 commercial Spanish wine samples. The validated method simultaneously determined both HT and its precursors, with adequatelimits of detection between 0.065 and 21.86 ng mL-1 and quantification limits between 0.199 and 66.27 ng mL-1 in a 5 min run. The concentration of HT in red wines was significantly higher (0.12-2.24 mg L-1) than in white wines (0.01-1.27 mg L-1). The higher the alcoholic degree, the higher was the content of HT. The bioactive 4-hydroxyphenylacetic acid was identified in Spanish wines for the first time at 3.90-127.47 mg L-1, being present in all the samples. The highest HT concentrations were found in red wines and in wines with higher ethanol content. These data are useful for a further estimation of the intake of these bioactive compounds and to enlarge knowledge on chemical composition of wines. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Conversion of wine lees and waste activated sludge into caproate and heptanoate: Thermodynamic and microbiological insights

In this study, wine lees and waste activated sludge (WAS) were co-fermented for the first time in a 4:1 ratio (COD basis) at 20, 40, 70 and 100 gCOD/L, in batch at 37 °C and pH 7.0. The substrates were successfully converted to caproate (C6) and heptanoate (C7) with a high selectivity (40.2 % at 40 gCOD/L). The rapidly-growing chain-elongating microbiome was enriched inClostridiaceaeandOscillospiraceae, representing together 3.4–8.8 % of the community. Substrate concentrations higher than 40 gCOD/L negatively affected C6 and C7 selectivities and yields, probably due to microbial inhibition by high ethanol concentrations (15.82–22.93 g/L). At 70 and 100 gCOD/L, chain elongation shifted from ethanol-based to lactate-based, with a microbiome enriched in the lactic acid bacteriaRoseburia intestinalis(27.3 %) andEnterococcus hirae(13.8 %). The partial pressure of H2(pH2) was identified by thermodynamic analysis as a fundamental parameter for controlling ethanol oxidation and improving C6 and C7 selectivities.

Biochemical and Biorefinery Platform for Second-Generation Bioethanol: Fermentative Strategies and Microorganisms

Bioethanol is the most commonly used biofuel. It is an alternative to replace fossil fuels in renewable energy; it can be produced from lignocellulosic feedstock using a biotechnological process. Their participation of microorganisms is crucial in the bioconversion process of fermentation for ethanol production and can involve bacteria, fungi, and yeasts. However, when working within bioethanol processes from lignocellulose feedstock, microorganisms face some challenges, such as high temperature, high solids content, and the ability to ferment sugars for high ethanol concentration. Such challenges will depend on operative strategies, such as simultaneous saccharification and fermentation, separate hydrolysis and fermentation, semi-simultaneous saccharification and fermentation, and consolidated bioprocessing; these are the most common configurations. This review presents different trends of the microbial role, biochemical application, and fermentation operative strategies for bioethanol production of the second generation.