Project description:Comparative profiling of fresh-cut lettuce samples treated with an alternative washing solution (PAA) with respect to standard treated samples STD (SH-treated).We generated a comprehensive repertory of transcripts useful to study the global change induced by two sanitizer in different time points of storage (T1, T3, and T6).
Project description:An untargeted metabolomics approach using UPLC-ESI-QTOF-MS was performed to explore the metabolome of iceberg lettuce and the changes related to storage time and genetics. Two cultivars with different browning susceptibility, fast- browning (FB) and slow-browning (SB) were studied juts after cutting (d0) and after 5 days of storage (d5). Extraction, metabolic profiling, and data-pretreatment procedures were optimized to obtain a robust and reliable data set. Preliminary principal component analysis (PCA) and hierarchical cluster analysis (HCA) of the full dataset (around 8551 extracted, aligned and filtered metabolites) showed a clear separation between the different samples (FB-d0, FB-d5, SB-d0, and SB-d5), highlighting a clear storage time-dependent effect. After statistical analysis applying Student´s t-test, 536 metabolites were detected as significantly different between d0 and d5 of storage in FB and 633 in SB. Some metabolites (221) were common to both cultivars. Out of these significant compounds, 22 were tentatively identified by matching their molecular formulae with those previously reported in the literature. Five families of metabolites were identified, some of them closely related to quality loss: amino acids, phenolic compounds, sesquiterpene lactones, fatty acids, and lysophospholipids. All compounds showed a clear trend to decrease at d5 except phenolic compounds that increased after storage. Overall, cutting and storage were shown to have a significant impact on the changes of lettuce metabolomics, with different trends depending on the browning susceptibility.
Project description:The widespread use of chemical inputs in agriculture has raised concern over their long-term environmental and health impacts, driving demand for sustainable, natural product-based alternatives. Peptide-hormone signaling interactions, particularly those regulating senescence, are promising targets for developing such alternatives to advance postharvest technologies. However, most current insights stem from model species, limiting their translation to crops and ornamental plants. This study identifies the CLAVATA3/EMBRYO-SURROUNDING REGION-related (CLE) family CLE12 peptide (CLE12p) in Lactuca sativa as a peptide that shows potential for postharvest management of crops and ornamental flowers. CLE12p interacts with salt (NaCl), abscisic acid (ABA) and ethylene pathways, influencing lettuce development and morphology. Notably, CLE12p induced stomatal closure in a similar manner to that of ABA, suggesting overlapping signalling pathways. Transcriptomic analyses revealed how CLE12p modulates immune and defence responses, fluid transport, and leaf senescence, indicating a broader role in leaf senescence regulation similar to that of ethylene. Functionally, CLE12p delayed senescence in lettuce by preserving leaf greenness and water content following dark treatment and harvest. Additionally, CLE12p extended the longevity of cut roses by maintaining fresh weight and water content. These findings demonstrate the practical potential of CLE peptides in non-model species and support their application as natural tools for extending postharvest shelf life in crops and ornamental plants, paving the way for further exploration of their role in agricultural biotechnology.
Project description:In the present study, we found a new walnut germplasm from wild Juglans cathayensis population, which presented white husk that did not brown. We compared the transcriptome between the fresh-cut browning (control) and white husks of the Chinese walnut using Illumina HiSeq 4000 platform
Project description:Lettuce is one of most consumed vegetables globally. This crop is susceptible to abiotic stresses. To understand the molecular mechanisms of stress response in lettuce, global transcriptome analysis was conducted. This analysis revealed distinctive temporal expression patterns among the stress-regulated genes in lettuce plants exposed to abiotic stresses
Project description:Nisin application delays growth of Listeria monocytogenes on fresh-cut iceberg lettuce, while the bacterial community structure changes within one week of storage.
Project description:Increasing evidence of Pseudomonas aeruginosa on fresh plant-based foods raises food safety concerns. While internalization of pathogens such as Salmonella enterica in vegetables such as lettuce is well documented, corresponding data for P. aeruginosa are lacking. Moreover, climate change-associated temperature shifts may influence the plant microbiota and the presence of human pathogens. This study investigates the internalization and temperature-dependent gene expression of P. aeruginosa PAO1 on green oak leaf lettuce as a model system. For this purpose, oak leaf lettuce was cultivated in soil inoculated with P. aeruginosa PAO1_sfGFP_UHH07, and internalization was analyzed using confocal laser scanning microscopy. Temperature-dependent transcriptomic changes of P. aeruginosa PAO1 were assessed by analyzing differentially expressed genes following plant inoculation and incubation at 18 and 22 °C, respectively. P. aeruginosa PAO1 is capable of internalizing into the roots of oak leaf lettuce, but a translocation into leaves was not detected. Transcriptomic analyses showed that a moderate temperature increase shifts bacterial gene expression, with virulence genes upregulated at 22 °C and persistence-associated genes predominating at 18 °C. These results show that temperature influences the persistence and pathogenic potential of P. aeruginosa present on oak leaf lettuce, highlighting potential impacts of climate change on food safety.