Bacterial population dynamics and decay on leaves of different ages of ready-to-use broad-leaved endive

Benchmarking of circular economy behaviors for Iraqi energy companies based on engagement modes with green technology and environmental, social, and governance rating

Greenhouse gas emissions and global warming are recent issues of upward trend. This study sought to underline the causal relationships between engagement modes with green technology, environmental, social, and governance (ESG) ratio, and circular economy. Our investigation also captured benchmarking of energy companies' circular economy behaviors. A hybrid-stage partial least squares structural equation modeling (PLS-SEM) and multi-criteria decision-making (MCDM) analysis have been adopted. This study collected 713 questionnaires from heads of departments and managers of energy companies. The findings of this study claimed that engagement modes with green technology affect the circular economy and sustainability. The findings revealed that ESG ratings have a mediating role in the nexus among engagement modes with green technology and circular economy. The results of the MCDM application revealed the identification of the best and worst energy companies of circular economy behaviours. This study is exceptional because it is among the first to address the issues of greenhouse gas emissions by providing decisive evidence about the level of circular economy behaviors in energy companies.

Shifts in the Bacterial Community Related to Quality Properties of Vacuum-Packaged Peeled Potatoes during Storage

To reveal the potential relationship between the bacterial community and quality attributes of vacuum-packaged peeled potatoes, the bacterial community dynamics, visual quality, organic acids, flavor and volatile organic compounds (VOCs) during 12 days of storage under 10 °C were studied, and a correlation analysis was performed between the bacterial community and VOCs. During the whole storage, the dominant bacteria changed from Ralstonia, Pseudomonas, Pantoea and Comamonas to Clostridia, Clostridium, Lacrimispora, Lactococcus and Leuconostoc. The visual quality and hardness deteriorated significantly on day 12; meanwhile, lactic and acetic acid content accumulated to 0.79 and 4.87 mg/g FW, respectively. Potatoes’ flavor deteriorated severely after 8 days, as evidenced by results of an electronic nose (e-nose). A total of 37 VOCs were detected, and the total content showed an increasing trend from 2164.85 to 10658.68 μg/kg during the whole storage. A correlation analysis showed that Enterobacteriaceae, Erwinia, Lacrimispora, Lactococcus, Serratia, Pantoea, Clostridium, Flavobacterium and Clostridia were positively correlated with the biosynthesis of VOCs. In addition, 10 spoilage markers were screened according to a variable importance in projection (VIP) ≥ 1. Ethanol, which was the most abundant spoilage marker, was significantly related to Enterobacteriaceae, Erwinia, Lacrimispora and Lactococcus. The results of this study have great practical significance for prolonging the shelf life of fresh-cut agricultural produce.

Behavior of Escherichia coli O157:H7 on damaged leaves of spinach, lettuce, cilantro, and parsley stored at abusive temperatures

Recent foodborne illness outbreaks associated with the consumption of leafy green produce indicates a need for additional information on the behavior of pathogenic bacteria on these products. Previous research indicates that pathogen growth and survival is enhanced by leaf damage. The objective of this study was to compare the behavior of Escherichia coli O157:H7 on damaged leaves of baby Romaine lettuce, spinach, cilantro, and parsley stored at three abusive temperatures (8, 12, and 15 degrees C). The damaged portions of leaves were inoculated with approximately 10(5) CFU E. coli O157:H7 per leaf. The pathogen grew on damaged spinach leaves held for 3 days at 8 and 12 degrees C (P < 0.05), with the population increasing by 1.18 and 2.08 log CFU per leaf, respectively. E. coli O157:H7 did not grow on damaged Romaine leaves at 8 or 12 degrees C, but growth was observed after 8 h of storage at 15 degrees C, with an increase of less than 1.0 log. Growth of E. coli O157:H7 on Romaine lettuce held at 8 or 12 degrees C was enhanced when inocula were suspended in 0.05% ascorbic acid, indicating the possibility of inhibition by oxidation reactions associated with tissue damage. Damaged cilantro and Italian parsley leaves held at 8 degrees C for 4 days did not support the growth of E. coli O157:H7. Behavior of the pathogen in leaf extracts differed from behavior on the damaged tissue. This study provides evidence that the damaged portion of a leafy green is a distinct growth niche that elicits different microbial responses in the various types of leafy greens.

Microbial and sensory quality of commercial fresh processed red lettuce throughout the production chain and shelf life

Red pigmented 'Lollo Rosso' lettuce was processed under usual and controlled conditions in an industrial plant. At different steps of the production chain (reception, shredding, washing, draining, rinsing, centrifugation, and packaging), microbial counts were evaluated. Following industrial practices, processed lettuce was packaged at 5 degrees C in sealed polypropylene (PP) bags with an initial atmosphere containing 3 kPa O(2) and 5 kPa CO(2). The numbers of psychrotrophic bacteria, coliform and lactic acid bacteria (LAB) were influenced by all the studied steps of the production chain of the fresh processed 'Lollo Rosso' lettuce. Shredding, rinsing and centrifugation in particular increased bacterial counts. During a storage period of 7 days at 5 degrees C, sensory attributes (general appearance, texture, aroma, translucency, initial and persistent off-odors, leaves superficial browning, leaves edges browning, and decay) as well as microbial counts (psychrotrophic and mesophilic bacteria, coliforms and lactic acid bacteria) were monitored. Due to high microbial counts and off-odors evaluation, a shelf life shorter than 7 days should be considered for fresh processed 'Lollo Rosso' lettuce.

The ecological significance of biofilm formation by plant-associated bacteria

Bacteria associated with plants have been observed frequently to form assemblages referred to as aggregates, microcolonies, symplasmata, or biofilms on leaves and on root surfaces and within intercellular spaces of plant tissues. In a wide range of habitats, biofilms are purported to be microniches of conditions markedly different from those of the ambient environment and drive microbial cells to effect functions not possible alone or outside of biofilms. This review constructs a portrait of how biofilms associated with leaves, roots and within intercellular spaces influence the ecology of the bacteria they harbor and the relationship of bacteria with plants. We also consider how biofilms may enhance airborne dissemination, ubiquity and diversification of plant-associated bacteria and may influence strategies for biological control of plant disease and for assuring food safety. Trapped by a nexus, coordinates uncertain Ever expanding or contracting Cannibalistic and scavenging sorties Excavations through signs of past alliances Consensus signals sound revelry Then time warped by viscosity Genomes showing codependence A virtual microbial beach party With no curfew and no time-out A few estranged cells seeking exit options, Looking for another menagerie. David Sands, Montana State University, Bozeman, February 2003

Effects of epiphytic Enterobacteriaceae and pseudomonads on the growth of Listeria monocytogenes in model media

Four Enterobacteriaceae (Enterobacter agglomerans and Rhanella aquatilis) and six pseudomonads (Pseudomonas fluorescens, Pseudomonas chlororaphis, Pseudomonas putida) isolated from minimally processed green endive were coinoculated at 10 degrees C with Listeria monocytogenes in a minimal medium. Pseudomonads did not modify the growth of L. monocytogenes, whereas Enterobacteriaceae reduced its maximal population by 2 to 3 log CFU/ml. The same effect was observed in a diluted yeast extract medium supplemented with amino acids and glucose, in which L. monocytogenes grown alone reached 10(9) to 10(10) CFU/ml. In the same diluted yeast extract medium, not supplemented with glucose and amino acids, the maximal population of L. monocytogenes in the presence of both Enterobacteriaceae and pseudomonads was only slightly reduced (less than 0.5 log CFU/ml). Culture filtrates of the Enterobacteriaceae had no inhibitory activity on L. monocytogenes. The effect of the Enterobacteriaceae on L. monocytogenes growth was presumably due to a competition for glucose and/or amino acids.