Fermentation

Traditional fermented beverages from Chiapas, Mexico, represent an important source of microbial diversity, particularly of Saccharomyces cerevisiae. In native strains isolated from traditional fermented beverages, Saccharomyces cerevisiae has been observed to display distinct morphological and physiological traits; therefore, the aim of this study was to evaluate the population growth and the tolerance of twenty isolates to different stress factors such as temperature, osmotic pressure, and high ethanol concentrations, as well as the genetic variability through interdelta analysis, and to determine whether these physiological and molecular characteristics are associated with the type of beverage and the locality of origin. Differences were observed in tolerance to various factors, including high ethanol concentrations and elevated temperatures, as well as in the production of volatile compounds, with Taberna and Mezcal isolates showing notable performance. These isolates were able to withstand temperatures ranging from 43 to 45 °C and ethanol concentrations of up to 17% in Mezcal and Pox isolates, and 15% in Taberna isolates. High concentrations of isoamyl acetate and higher alcohols such as isoamyl alcohol were detected. In addition, the genetic variability of the isolates was evaluated, and its relationship with the type of beverage and the geographical origin of production was explored, including isolates obtained from Taberna, Mezcal, Pox, and Chicha de Chilacayote. Intraspecific variability was assessed through a retrotransposon-based analysis of the interdelta region using different primer combinations (δ1-δ2, δ12-δ21, and δ12-δ2). The generated banding patterns were analyzed using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA), which enabled the identification of molecular variability patterns among the isolates. Furthermore, a UPGMA analysis was performed using physiological and compound production data, revealing a relationship between these characteristics and the geographical origin of the isolates. The results revealed a high degree of intraspecific variability, which was associated with both the type of beverage and the locality of origin of the isolates.

Brazil is one of the world’s largest producers of grains and cattle, activities that generate a large amount of organic waste, which has high potential for biogas and methane production. Cattle manure (CM) and industrial waste from corn processing are substrates with significant potential for biogas and methane generation, particularly through the process of anaerobic co-digestion (AcoD). This study aimed to assess the biogas and methane yield, as well as the stability of the AcoD process involving CM and corn grain residues (CG) derived from a grain processing agroindustry, in conjunction with the application of an enzyme complex. The experiment was conducted in plug-flow biodigesters, with a total volume of 28 L, under a semi-continuous feeding regime (OLR = 0.84 g vs. L d⁻¹) at ambient temperature. The findings indicated increases in daily biogas and methane production for AcoD, without the addition of enzymes, of 52.1% and 44.4%, respectively, in comparison to CM mono-digestion. The incorporation of the enzyme complex did not yield beneficial effects, irrespective of the substrate composition. The utilization of enzymes in semi-continuous biodigesters to enhance methane yields necessitates further investigation to achieve favorable outcomes and validate its efficiency.

Yeast-derived biomolecules are redefining the boundaries of green nanotechnology. Biosurfactants, exopolysaccharides, enzymes, pigments, proteins, and organic acids—when sourced from carbohydrate-rich lignocellulosic hydrolysates—offer a molecular toolbox capable of directing, stabilizing, and functionalizing nanoparticles (NPs) with unprecedented precision. Beyond their structural diversity and intrinsic biocompatibility, these biomolecules anchor a paradigm shift: the convergence of biorefineries with nanotechnology to deliver multifunctional materials for the circular bioeconomy. This review explores: (i) the expanding portfolio of metallic and metal oxide NPs synthesized through yeast biomolecules; (ii) molecular-level mechanisms of reduction, capping, and surface tailoring that dictate NP morphology, stability, and reactivity; (iii) synergistic roles in intensifying lignocellulosic processes—from enhanced hydrolysis to catalytic upgrading; and (iv) frontier applications spanning antimicrobial coatings, regenerative packaging, precision agriculture, and environmental remediation. We highlight structure–function relationships, where amphiphilicity, charge distribution, and redox activity govern resilience under saline, acidic, and thermally harsh industrial matrices. Yet, critical bottlenecks remain: inconsistent yields, limited comparative studies, downstream recovery hurdles, and the absence of comprehensive life-cycle and toxicological evaluations. To bridge this gap, we propose a translational roadmap coupling standardized characterization with real hydrolysate testing, molecular libraries linking biomolecule chemistry to NP performance, and integrated techno-economic and environmental assessments. By aligning yeast biotechnology with nanoscience, we argue that yeast-biomolecule-driven nanoplatforms are not merely sustainable alternatives but transformative solutions for next-generation lignocellulosic biorefineries.