42 research outputs found
Modes of antibacterial action of curcumin under dark and light conditions: A toxicoproteomics approach
Brief postharvest exposure to pulsed light stimulates coloration and anthocyanin accumulation in fig fruit (Ficus carica L.)
Antimicrobial coatings on polyethylene terephthalate based on curcumin/cyclodextrin complex embedded in a multilayer polyelectrolyte architecture
Effects of Compostable Packaging and Perforation Rates on Cucumber Quality during Extended Shelf Life and Simulated Farm-to-Fork Supply-Chain Conditions
Cucumbers are highly perishable and suffer from moisture loss, shriveling, yellowing, peel damage, and decay. Plastic packaging helps to preserve cucumber quality, but harms the environment. We examined the use of compostable modified atmosphere packaging (MAP) with different perforation rates as a possible replacement for conventional plastic packaging materials. The results indicate that all of the tested types of packaging reduced cucumber weight loss and shriveling. However, compostable MAP with micro-perforations that created a modified atmosphere of between 16–18% O2 and 3–5% CO2 most effectively preserved cucumber quality, as demonstrated by reduced peel pitting, the reduced appearance of warts and the inhibition of yellowing and decay development. Overall, micro-perforated compostable packaging extended the storage life of cucumbers under both extended shelf conditions and simulated farm-to-fork supply-chain conditions and thus may serve as a replacement for the plastic packaging currently used to preserve the postharvest quality of cucumbers
Investigating the Antibacterial Effect of a Novel Gallic Acid-Based Green Sanitizer Formulation
The purpose of the present study was to investigate the mechanism of action of our newly developed green sanitizer formulation comprising a natural phenolic compound, gallic acid (GA), strengthened by the Generally Recognized as Safe (GRAS) materials hydrogen peroxide (H2O2) and DL-lactic acid (LA). Combining 8 mM GA with 1 mM H2O2 resulted in an abundant generation of reactive oxygen species (ROS) and a bactericidal effect towards Gram-negative (Escherichia coli, Pseudomonas syringae, and Pectobacterium brasiliense) and Gram-positive (Bacillus subtilis) bacteria (4 to 8 log CFU mL−1 reduction). However, the exposure to this dual formulation (DF) caused only a modest 0.7 log CFU mL−1 reduction in the Gram-positive L. innocua population. Amending the DF with 20 mM LA to yield a triple formulation (TF) resulted in the efficient synergistic control of L. innocua proliferation without increasing ROS production. Despite the inability to grow on plates (>7 log CFU mL−1 population reduction), the TF-exposed L. innocua maintained high intracellular ATP pools and stable membrane integrity. The response of L. innocua to TF could be qualified as a “viable but nonculturable” (VBNC) phenomenon, while with the other species tested this formulation caused cell death. This research system may offer a platform for exploring the VBNC phenomenon, a critical food safety topic
Enhancement of Glucosinolate Formation in Broccoli Sprouts by Hydrogen Peroxide Treatment
Broccoli sprouts are known as a rich source of health-beneficial phytonutrients: glucosinolates and phenolic compounds. The production of phytonutrients can be stimulated by elicitors that activate the plant stress response. The aim of this study was enhancing the nutritional value of broccoli sprouts using hydrogen peroxide (H2O2) as an elicitor. Daily spraying with H2O2 (500–1000 mM) enhanced the accumulation of glucosinolates, doubling their content in the cotyledons of 16/8 h photoperiod-grown 7-day sprouts compared to the water-treated controls. The application of H2O2 on dark-grown sprouts showed a smaller extent of glucosinolate stimulation than with light exposure. The treatment affected sprout morphology without reducing their yield. The H2O2-treated sprouts had shorter hypocotyls and roots, negative root tropism and enhanced root branching. The activated glucosinolate production became evident 24 h after the first H2O2 application and continued steadily until harvest. Applying the same treatment to greenhouse-grown wild rocket plants caused scattered leaf bleaching, a certain increase in glucosinolates but decline in phenolics content. The H2O2 treatment of broccoli sprouts caused a 3.5-fold upregulation of APK1, a gene related to sulfur mobilization for glucosinolate synthesis. Comparing the APK1 expression with the competing gene GSH1 using sulfur for antioxidant glutathione production indicated that glutathione synthesis prevailed in the sprouts over the formation of glucosinolates
