vegetables, which include broccoli, kale, cauliflower, and Brussel sprouts, are known for their high glucosinolate content. Glucosinolates and their derived forms namely isothiocyanates are of special interest in the pharmaceutical and food industries due to their antimicrobial, neuroprotective, and anticarcinogenic properties. These compounds are water soluble and heat-sensitive and have been proved to be heavily lost during thermal processing. In addition, previous studies suggested that novel non-thermal technologies such as high pressure processing, pulsed electric fields, or ultraviolet irradiation can affect the glucosinolate content of cruciferous vegetables. The objective of this paper was to review current knowledge about the effects of both thermal and non-thermal processing technologies on the content of glucosinolates and their derived forms in vegetables. This paper also highlights the importance of the incorporation of vegetables into our diet for their health-promoting properties beyond their anticarcinogenic activities.

In order to identify tobacco (Nicotiana megalosiphon) genes involved in broad-spectrum resistance to tobacco blue mold (Peronospora hyoscyami f. sp. tabacina), suppression subtractive hybridization was used to generate cDNA from transcripts that are differentially expressed during an incompatible interaction. After differential screening by membrane-based hybridization, clones corresponding to 182 differentially expressed genes were selected, sequenced, and analyzed. The cDNA collection comprised a broad repertoire of genes associated with various processes. Northern blot analysis of a subset of these genes confirmed the differential expression patterns between the compatible and incompatible interaction. Subsequent virus-induced gene silencing (VIGS) of four genes that were found to be differentially induced was pursued. While VIGS of a lipid transfer protein gene or a glutamate decarboxylase gene in Nicotiana megalosiphon did not affect blue mold resistance, silencing of an EIL2 transcription factor gene and a glutathione synthetase gene was found to compromise the resistance of Nicotiana megalosiphon to P. hyoscyami f. sp. tabacina. Potentially, these genes can be used to engineer resistance in blue mold-susceptible tobacco cultivars.

The present study was aimed at gaining insight into the mode of action of the antagonistic bacteria Pseudomonas graminis CPA-7, which has been previously identified as an effective biocontrol agent against Listeria monocytogenes, Salmonella enterica and Escherichia coli O157:H7 on fresh-cut fruit. In vitro experiments did not reveal any antimicrobial or proteolytic activity on solid media or any biosurfactant activity on hydrophobic surfaces. Metabolites produced by CPA-7 in two different culture media and on 'Galia' melon were unable to inhibit L. monocytogenes populations on 'Galia' melon plugs at 25 °C or 5 °C. In contrast, at 25 °C the population of this pathogen on 'Galia' plugs was reduced by 2.1 and 3.3 log-units when coinoculated with the antagonist in water, after 24 and 48 h, respectively. CPA-7 did not form biofilms after 72 h at 25 °C (OD=0.03) or at 30 °C (OD=0.01) on polystyrene plates and the production of alginate was close to the negative control. Studies of nutritional profiles showed high overlap (NOI>0.9) between CPA-7 and E. coli O157:H7 regarding the use of carboxylic acids. This functional group could also contain putative 2 targets for competiveness between CPA-7 and S. enterica, although overlapping was not restrictive enough (NOI=0.83).

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The effectiveness of a water-assisted UV-C (WUV) technology for the decontamination of fresh-cut broccoli from conventional and organic agricultural practices was evaluated as an alternative to chlorine sanitation. Several WUV doses (0.3-1.8 kJ m-2) were tested alone or combined with peroxyacetic acid (PAA). Results showed that 0.5 kJ m-2 was sufficient to reduce natural total aerobic mesophilic microorganisms by 2 log 10 in conventional broccoli without 2 negative consequences on the physical quality. However, in order to achieve the same effect on organic broccoli, a combined application of at least 0.3 kJ m-2 and 50 mg L-1 PAA was required. Total antioxidant capacity (TAC) was enhanced by 42, 90 and 81% in conventional broccoli 24 h after treatment with 0.3, 0.5 and 1.8 kJ m-2 , respectively, compared to watercontrol. A similar trend was observed in organic broccoli, although the increase in TAC (by 22%) compared to the water-control was only significant when a dose of 1.8 kJ m-2 was used. Similarly, 0.5 kJ m-2 enhanced the sulforaphane content in conventional broccoli by 1.5 and 4fold compared to water and chlorine-controls, respectively. WUV is a promising alternative technology to improve the microbiological and nutritional quality of fresh-cut broccoli.

The efficacy of two irradiation technologies: Ultraviolet-C light (UV-C), applied in water or in peroxyacetic acid, and dry-pulsed light (PL), for the inactivation and growth inhibition of Listeria innocua populations in fresh-cut broccoli, were evaluated. Water-assisted UV-C (WUV) (0.3 and 0.5 kJ m-2) reduced L. innocua initial populations by 1.7 and 2.4 log 10 , respectively; the latter dose also inhibited the growth for 8 d at 5 ºC. Replacing water with 40 or 80 mg L-1 peroxyacetic acid did not improve this efficacy. Pulsed light (5, 10, 15, and 20 kJ m-2) showed no effect on broccoli's native microbiota. Neither did 15 kJ m-2 PL inactivate L. innocua or inhibit its growth. Nonetheless, 24 h post-processing, PL (15 kJ m-2) increased total phenolic content by 25 % in respect of chlorine-sanitation, and enhanced total antioxidant capacity by 12 and 18 % compared to water and chlorine controls, respectively. Unlike dry-PL, WUV is a suitable technology for controlling L. monocytogenes populations in fresh-cut broccoli. Industrial relevance The present work provides relevant information to the fresh-cut food industry regarding a suitable decontamination alternative to chlorine sanitation. Low-dose immersion-assisted UV-C allows inactivation and inhibition of native and pathogenic microbiota while generates non-toxic byproducts and allows reusing the process water thereby enabling savings in water consumption. The results obtained herein provide new tools to ensure both quality and safety of minimally processed products, contributing to the so-called "smart green growth" addressed to provide a more innovative and sustainable future for the food industry.