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During alcoholic fermentation, ethanol accumulation significantly impacts yeast cells by disrupting membrane integrity, increasing permeability, and reducing cell viability. This study evaluated the effects of ethanol stress on the growth, membrane fluidity, and cell surface morphology of Saccharomyces cerevisiae and non-Saccharomyces yeast strains, specifically Torulaspora delbrueckii and Metschnikowia pulcherrima. These strains, commercialized by AEB SpA and preserved at the Unimore Microbial Culture Collection (UMCC), were tested for fermentative performance in grape must and grown under varying ethanol concentrations. Membrane fluidity was measured using Laurdan generalized polarization (GP), while Atomic Force Microscopy (AFM) assessed cell surface morphology. Results indicated that at 10% ethanol, membrane fluidity increased, particularly in strains able to tolerate up to 16% ethanol, which also demonstrated superior fermentative performance. Less tolerant strains, such as T. delbrueckii UMCC 5 and M. pulcherrima UMCC 15, showed smaller increases in fluidity. At 18% ethanol, these strains exhibited severely altered surface morphology and larger surface roughness values, suggesting increased instability under high ethanol stress, while more tolerant strains displayed better-preserved surface morphology and lower roughness values, reflecting enhanced adaptability. These findings offer insights into yeast responses to ethanol stress, supporting the development of more resilient strains for improved fermentation. [ABSTRACT FROM AUTHOR]

In this work we examined the contents of 14 polyphenols in white lupin (Lupinus albus L.) samples cultivated in Southern Italy by the optimisation and validation of a LC-HRMS method. The validation of the LC-HRMS method showed linearity results r2 > 0.989 and recovery values between 71 and 119% for a very wide range of concentrations. Ellagic acid was the most abundant polyphenol, with mean concentrations of 16271.86 ± 19798.53 μg/Kg, followed by apigenin (2749.51 ± 889.95 μg/Kg). A significant variability in ellagic acid contents was found between the areas of cultivation examined (p < 0.05). As far as we know, this work provides the first data on the polyphenols contents of white lupins cultivated in Italy. The comparison with other study confirms the role of the cultivation area for the determination of the polyphenol's contents. The study also confirms white lupins as a promising source of antioxidant and anti-inflammatory substances in a balanced diet. [ABSTRACT FROM AUTHOR]

The presence of polyphenols was examined in carob pods ( Ceratonia siliqua ) from Southern Italy 90 days after harvest by the validation of a reliable LC-HRMS method. A greater abundance of Apigenin (51490.22 ± 34399.16 μg/Kg) and Myricetin (24897.92 ± 108332.05 μg/Kg) compared to previous research works conducted in Mediterranean countries. Significant differences in the polyphenol content between sampling areas ( p  < 0.05) were observed, particularly differences in hesperidin and myricetin. These differences confirmed the role of geochemical and climatic conditions in the variation of polyphenol content. This study is a first regarding the phenolic content of carob pods from Southern Italy, confirming the presence of these substances even long after harvest and that carob pods are valuable sources of phenolic substances that may be useful in the prevention of diseases related to oxidative stress.