Unraveling the potential of non-conventional yeasts in biotechnology.

Cost-effective microbial conversion processes of renewable feedstock into biofuels and biochemicals are of utmost importance for the establishment of a robust bioeconomy. Conventional baker's yeast Saccharomyces cerevisiae, widely employed in biotechnology for decades, lacks many of the desired traits for such bioprocesses like utilization of complex carbon sources or low tolerance towards challenging conditions. Many non-conventional yeasts (NCY) present these capabilities, and they are therefore forecasted to play key roles in future biotechnological production processes. For successful implementation of NCY in biotechnology, several challenges including generation of alternative carbon sources, development of tailored NCY and optimization of the fermentation conditions are crucial for maximizing bioproduct yields and titers. Addressing these challenges requires a multidisciplinary approach that is facilitated through the 'YEAST4BIO' COST action. YEAST4BIO fosters integrative investigations aimed at filling knowledge gaps and excelling research and innovation, which can improve biotechnological conversion processes from renewable resources to mitigate climate change and boost transition towards a circular bioeconomy. In this perspective, the main challenges and research efforts within YEAST4BIO are discussed, highlighting the importance of collaboration and knowledge exchange for progression in this research field

Obstetric–Neonatal Care during Birth and Postpartum in Symptomatic and Asymptomatic Women Infected with SARS-CoV-2: A Retrospective Multicenter Study

Data Availability Statement: Data are available upon reasonable request. All necessary data are supplied and available in the manuscript; however, the corresponding author will provide the dataset upon request. All data relevant to the study are included in the article.Copyright © 2022 by the authors. This study analyses the obstetric–neonatal outcomes of women in labour with symptomatic and asymptomatic COVID-19. A retrospective, multicenter, observational study was carried out between 1 March 2020 and 28 February 2021 in eight public hospitals in the Valencian community (Spain). The chi-squared test compared the obstetric–neonatal outcomes and general care for symptomatic and asymptomatic women. In total, 11,883 births were assisted in participating centers, with 10.9 per 1000 maternities (n = 130) infected with SARS-CoV-2. The 20.8% were symptomatic and had more complications both upon admission (p = 0.042) and during puerperium (p = 0.042), as well as transfer to the intensive care unit (ICU). The percentage of admission to the Neonatal Intensive Care Unit (NICU) was greater among offspring of symptomatic women compared to infants born of asymptomatic women (p < 0.001). Compared with asymptomatic women, those with symptoms underwent less labour companionship (p = 0.028), less early skin-to-skin contact (p = 0.029) and greater mother–infant separation (p = 0.005). The overall maternal mortality rate was 0.8%. No vertical transmission was recorded. In conclusion, symptomatic infected women are at increased risk of lack of labour companionship, mother–infant separation, and admission to the ICU, as well as to have preterm births and for NICU admissions.FISABIO grant number UGP-20-24

Hybridization and adaptive evolution of diverse Saccharomyces species for cellulosic biofuel production

Additional file 15. Summary of whole genome sequencing statistics

Realistic approach for full-scale bioethanol production from lignocellulose: a review

874-884This paper reviews current status of bioethanol production including substrates, fermenting microorganisms and technology for a full-scale process development. Considering main drawbacks, several parameters (high substrate loadings, sugar recovery after pretreatment, tolerance to inhibitory compounds and xylose fermentation by yeast) must be optimized for a successful industrial process for bioethanol production from lignocellulose

Short-term adaptation during propagation improves the performance of xylose-fermenting Saccharomyces cerevisiae in simultaneous saccharification and co-fermentation

© 2015 Nielsen et al. Background: Inhibitors that are generated during thermochemical pretreatment and hydrolysis impair the performance of microorganisms during fermentation of lignocellulosic hydrolysates. In omitting costly detoxification steps, the fermentation process relies extensively on the performance of the fermenting microorganism. One attractive option of improving its performance and tolerance to microbial inhibitors is short-term adaptation during propagation. This study determined the influence of short-term adaptation on the performance of recombinant Saccharomyces cerevisiae in simultaneous saccharification and co-fermentation (SSCF). The aim was to understand how short-term adaptation with lignocellulosic hydrolysate affects the cell mass yield of propagated yeast and performance in subsequent fermentation steps. The physiology of propagated yeast was examined with regard to viability, vitality, stress responses, and upregulation of relevant genes to identify any links between the beneficial traits that are promoted during adaptation and overall ethanol yields in co-fermentation. Results: The presence of inhibitors during propagation significantly improved fermentation but lowered cell mass yield during propagation. Xylose utilization of adapted cultures was enhanced by increasing amounts of hydrolysate in the propagation. Ethanol yields improved by over 30 % with inhibitor concentrations that corresponded to ≥2.5 % water-insoluble solids (WIS) load during the propagation compared with the unadapted culture. Adaptation improved cell viability by >10 % and increased vitality by >20 %. Genes that conferred resistance against inhibitors were upregulated with increasing amounts of inhibitors during the propagation, but the adaptive response was not associated with improved ethanol yields in SSCF. The positive effects in SSCF were observed even with adaptation at inhibitor concentrations that corresponded to 2.5 % WIS. Higher amounts of hydrolysate in the propagation feed further improved the fermentation but increased the variability in fermentation outcomes and resulted in up to 20 % loss of cell mass yield. Conclusions: Short-term adaptation during propagation improves the tolerance of inhibitor-resistant yeast strains to inhibitors in lignocellulosic hydrolysates and improves their ethanol yield in fermentation and xylose-fermenting capacity. A low amount of hydrolysate (corresponding to 2.5 % WIS) is optimal, whereas higher amounts decrease cell mass yield during propagation