Project description:Fresh fish are highly perishable food products and their short shelf-life limits their commercial exploitation, leads to waste and has a negative impact on aquaculture sustainability. New non-thermal food processing methods, such as High pressure (HP), are being investigated to prolong shelf-life while assuring high food quality. We applied several tools to evaluate the impacts of HP processing on European sea bass (Dicentrarchus labrax) fillets quality and shelf life. The data here presented includes visual and physical measurements of flesh quality and the microbiome and proteome profiles of control and HP-processed sea bass fillets (600MPa, 25ºC, 5min), after isothermal storage (2°C) for different periods ranging from 1 to 67 days. Color (L-, a- and b- values) change and texture (hardness, cohesiveness and adhesiveness) parameters were obtained by using appropriate colorimeter and texture analyser, respectively, during refrigerated storage. Bacterial diversity was analysed by Illumina high-throughput sequencing of the 16S rRNA gene in five pooled DNAs from control or HP-processed fillets after 1, 11 or 67 days and the raw reads were deposited in the NCBI-SRA database with accession number PRJNA517618. In addition, high-throughput sequencing of the internal transcribed spacer (ITS) region targeting yeast and moulds was run for control or HP-processed fillets at the end of storage (11 or 67 days, respectively), being deposited under SRA accession PRJNA517779. Quantitative label-free proteomics profiles were analysed by SWATH-MS (Sequential Windowed data independent Acquisition of the Total High-resolution-Mass Spectra) in myofibrillar or sarcoplasmic enriched protein extracts pooled for control or HP-processed filets after short (1d) or long-term (11-67 days) storage. These data support the findings reported in “High pressure processing of European sea bass (Dicentrarchus labrax) fillets and tools for flesh quality and shelf life monitoring” (Tsironi et al. 2019).
Project description:Lettuce (Lactuca sativa L.) is a highly perishable horticultural crop with a relatively short shelf life due to leaf senescence that limits its commercial value and contributes to food waste. Postharvest senescence varies with influences of both environmental and genetic factors. Preharvest genetic factors can be indicative of postharvest quality. Discovery of additional preharvest markers to assess lettuce shelf life is an important step towards increasing the efficiency of lettuce breeding efforts for improved shelf life. We selected and evaluated three romaine lettuces with variable shelf lives with the aim of identifying preharvest markers of lettuce postharvest shelf life. We evaluated leaf morphological characteristics for each of the three cultivars. To assess molecular indicators of shelf life, we used an RNA sequencing approach to construct transcriptomic profiles of two of the cultivars, a short shelf life (SSL) breeding line 60184 and a long shelf life (LSL) cultivar ‘Okeechobee’ at maturity. We identified 552 upregulated and 315 downregulated differentially expressed (DE) genes between the genotypes. We found that 27 % of the DE lettuce genes had an Arabidopsis thaliana ortholog characterized as senescence-associated, indicating that variable expression of senescence-associated genes (SAGs) could serve as a tool for preharvest markers of postharvest shelf life. Notably, we identified several SAGs and functional groupings with highly differential expression between the cultivars. This includes several jasmonate ZIM-domain (JAZ), jasmonic acid (JA) signaling genes, chlorophyll a-b binding (CAB) chloroplast-associated genes, and cell wall modification genes including pectate lyases (PL) and expansins (EXP). This study presented an innovative approach for identifying molecular markers for preharvest factors linked to postharvest traits for prolonged shelf. These genes could potentially be developed further as preharvest predictors of shelf life for lettuce breeding
Project description:Recombinant human erythropoietin administration studies involving transcriptomic approaches have demonstrated a gene-expression signature that could aid detection of blood doping. However, current anti-doping testing does not involve blood collection into tubes with RNA preservative. This study investigated if whole blood in long-term storage and whole blood leftover from standard haematological testing in short-term storage could be used for transcriptomic analysis despite lacking RNA preservative. Whole blood samples were collected from thirteen and fourteen healthy males, for long-term and short-term storage experiments. Long-term storage: whole blood collected into Tempus™ tubes and K2EDTA tubes and subjected to long-term (i.e., −80°C) storage and RNA extracted. After storage, K2EDTA tubes were thawed and extracted using GeneJET RNA Purification Kit (Thermo Fisher Scientific, Vilnius, Lithuania) or Tempus™ Spin RNA Isolation Kit (Life Technologies, Carlsbad, CA, USA). RNA quality and purity was sufficient for gene expression analysis. Principle Component Analysis of microarray and RNA-seq gene expression data for long-term storage: When comparing gene expression between blood tubes with and without RNA preservation, 6% (4058 transcripts) were differentially expressed. RNA quantity, purity and integrity was not significantly compromised from long-term storage in blood storage tubes lacking RNA preservative, indicating that transcriptomic analysis could be conducted using anti-doping samples collected or biobanked without RNA preservation.
Project description:Purpose: This study was to explore the underlying molecular mechanism of temperature effects on fruit quality during shelf life. The transcriptome data of peach fruits stored in high temperature (HT, 35 °C) and common temperature (CT, 25 °C) conditions were measured and compared. Methods: Red flesh peach (Prunus persica L. Batsch cv. Tianxianhong) fruits with consistent color, shape and weight were selected and kept at 5 °C for 2 days after the day of harvest. Then, these fruits were randomly divided into two groups. One group was stored at CT for 7 days, and the other was stored at HT for 7 days. During storage, fruits were sampled at day 1, 2 and 3 as early stage as well as day 5, 6 and 7 as later stage. Total RNA of each sample was extracted and used to construct 24 RNA libraries. RNA sequencing was performed on an Illumina HiSeq 2500 platform. The differences in transcriptome, ethylene production, pulp softening of postharvest peach fruits were compared between CT and HT storage conditions Results: Our results showed that HT conditioning after 5 °C is better than CT to maintaining fruit quality during shelf life due to MEKK1-MKK2-MPK4/6 signal transduction and low level of ethylene and auxin biosynthesis enzymes which may affect genes related to softening and membrane stability through ethylene response factors (ERFs) and auxin response factors (ARFs).