Staphylococcus aureus is a major food safety concern because of its ability to produce heat-stable enterotoxins, develop antimicrobial resistance, and express virulence factors associated with persistence and pathogenicity. The present study characterised S. aureus isolates recovered from ready-to-eat (RTE) foods and food handlers’ hands in university food service establishment in northern Portugal, focusing on virulence-associated genes, antimicrobial resistance profiles, and biofilm production. A total of 261 samples were analysed, including 156 RTE food samples and 105 hand swabs. Twenty-nine coagulase-positive staphylococci isolates were recovered and confirmed as S. aureus by detection of the nuc gene, corresponding to an overall prevalence of 11.11% (29/261). Of these, 20 isolates were obtained from food handlers’ hands and 9 from RTE foods. The hla and sei genes were detected in all isolates, while seg and tst were detected in 93.10%; sed was not detected. Biofilm-forming capacity was identified in 44.83% of isolates, with most strains exhibiting weak to moderate biofilm production. Resistance to at least one antimicrobial agent was observed in 31.0% of isolates, and presumptive methicillin-resistant Staphylococcus aureus represented 13.79%, all classified as multidrug-resistant. These findings support the occurrence of handling-related contamination and reinforce the need for strict hygiene practices, temperature control, and continuous monitoring in institutional food service environments.

Climate change significantly impacts fruit production and yield, affecting its commercial value. Foliar fertilization emerges as a fast and targeted strategy to address crop nutrient deficiencies and enhance fruit quality. Sweet cherry is among the most highly valued and widely appreciated fruit crops globally. This study was conducted over two consecutive years on the sweet cherry cv. Sweetheart. Calcium (300 g hL−1 and 150 g hL−1) and a seaweed-based biostimulant (150 mL hL−1 and 75 mL hL−1), as well as a combination of both nutrients (300 g hL−1 calcium and 150 mL hL−1 seaweed), in addition to a control treatment (water), were applied at the foliar level to improve sweet cherry quality. To assess cherry quality, including biometric, chromatic, texture, and biochemical parameters, as well as the sensory analysis, fruits from each treatment were harvested at the commercial maturity stage. Calcium treatments improved fruit size, total soluble solids, and firmness, while also delaying fruit ripening by increasing titratable acidity. The seaweed-based biostimulant enhanced fruit size, promoted color development, and accelerated ripening. Together, these findings highlight the crucial role of calcium in improving sweet cherry quality and underscore seaweed-based biostimulants as a promising and sustainable strategy for enhancing fruit quality. Although cherry quality is highly affected by environmental conditions, this study demonstrated that calcium fertilization, either alone or in combination with seaweed, enhances sweet cherry quality attributes, making it a suitable strategy for application in commercial orchards and for the global improvement of sweet cherry production.

BACKGROUND:Sweet cherry is highly valued around the world for its sensory qualities. Bioactive properties play significant roles in sweet cherry quality and consumer acceptance due to its health benefits. Plant nutrition through balanced fertilizer application helps in abiotic stresses mitigation, enhancing the biosynthesis of bioactive substances. For three consecutive years, magnesium (Mg) and potassium (K) were applied as foliar sprays to sweet cherry trees of the Burlat cultivar, with the aim to improve phytochemical composition. Fruits from each treatment were harvested at the commercial ripening stage to evaluate cherry bioactive composition and antioxidant activity. RESULTS:Overall, the phytochemical composition and antioxidant activity increased over the three trial years, reaching their highest values in 2021, highlighting the effects of continuous fertilization with Mg and K. The Mg treatments (especially Mg250 in 2019 and Mg125 in 2020) enhanced the phytochemical composition of sweet cherries by increasing total phenolics, flavonoids, ortho-diphenols, and anthocyanin contents, as well as boosting antioxidant activity. In contrast, K treatments (mainly K50) led to a decrease in all bioactive compounds and antioxidant activity. The levels of individual phenolic compounds varied across treatments; however, catechin, epicatechin, chlorogenic acid, and quercetin-3-O-rutinoside contents declined over the 3 years, while neochlorogenic acid and cyanidin-3-O-rutinoside levels increased, stabilizing in 2020 and 2021. CONCLUSIONS:These findings offer valuable insights for enhancing sweet cherry bioactive properties. © 2025 Society of Chemical Industry.

Fruit cracking is a developmental defect depending on genetic and environmental conditions. Fruit cracking has a negative impact on quality and production. Fruits with cracking cannot be commercialized and enhance pathogen contaminations. Identifying genes as markers may help in breeding and post-harvest treatments. We compared qPCR and dPCR methods using a set of 16 genes that appear to be differentially expressed in the cherry varieties Sweatheart with low cracking and Burlat with high cracking indexes. Differences in absolute transcripts spanned across nearly three orders of magnitude. Overall qPCR and dPCR show a highly significant negative correlation of -0.90. The equation allowed converting Ct values to dPCR copy number. However, copy number in dPCR allow a direct comparison across experiments and transcriptomic analysis. The combination of PaCER1, PaXTH, PaEXP1, PaEXP2, PaKCS6, PaWINA, PaWINB and PaCER3 as an expression bitmap can separate cherry fruits with low and high cracking phenotypes based on gene expression. Our results highlight the importance of the wax biosynthesis and cell wall metabolic pathways in susceptibility to fruit cracking. Furthermore, the newly identified bitmap may be useful to test in other locations and with different varieties.

Modern fruit crop production increasingly seeks sustainable strategies to enhance growth, yield, and fruit quality while minimizing environmental impacts. Plant biostimulants—naturally derived substances or beneficial microorganisms, such as seaweed and plant extracts, Plant-Growth-Promoting Rhizobacteria (PGPR), humic substances, protein hydrolysates, and Si—emerge as promising tools to achieve these goals by stimulating key physiological and biochemical processes. They can improve nutrient uptake and efficiency, modulate hormonal and metabolic pathways, and enhance the activity of enzymatic and non-enzymatic antioxidants, leading to improved plant vitality and fruit quality. Biostimulants also influence rhizosphere microbial communities and soil health, promoting nutrient cycling, beneficial microbial diversity, and soil structure. This review evaluates the application of biostimulants in fruit crops and their effects on growth, physiology, productivity, fruit quality, both chemical and nutritional composition and physical parameters. Challenges related to variability in efficacy, formulation standardization, and crop-specific responses are discussed, alongside future perspectives on integrating biostimulants into sustainable orchard management. Overall, biostimulants represent multifunctional tools that support both productivity and ecological sustainability in modern fruit production systems.