Understanding the effect of postharvest tomato temperatures on two toxigenic Alternaria spp. strains: growth, mycotoxins and cell-wall integrity-related gene expression

BackgroundTomato fruits are susceptible to Alternaria spp. spoilage. A correct postharvest management is necessary to prevent mould growth and mycotoxin accumulation, being the temperature one of the main factors. The effect of different postharvest temperatures (5, 12, 25 and 35 °C) on growth, mycotoxin production and a stress-related gene expression by two Alternaria spp. was assessed. ResultsGrowth rates decreased rapidly when temperature was higher than the optimum (25 °C), while a gradual reduction was detected at lower temperatures. Tenuazonic acid (TeA) was strongly synthesised at all temperatures evaluated, with a maximum between 12 and 25 °C. Alternariol monomethyl ether (AME) was produced only at the two lowest temperatures; with a peak at 12 °C. Regarding the expression of the stress-related RHO1 gene, during active fungal growth both Alternaria spp. showed more copies of the gene as temperature increased. At the stationary phase, the RHO1 gene expression was significantly higher at 12 °C, coinciding with AME highest accumulation. ConclusionChanges on temperatures related to different postharvest stages of tomato fruits markedly affect toxigenic Alternaria spp. The highest levels of both mycotoxins were recorded at 12 °C, a common storage temperature for tomato fruit. Additionally, an association between alternariols biosynthesis and the cell wall integrity pathway was noticed in relation to temperature, suggesting that temperature may act as stressor stimulating the RHO1 gene expression, which in turn triggers this mycotoxin synthesis. These results will be useful in developing new strategies to efficiently control Alternaria spoilage in tomato fruit and by-products.Fil: Da Cruz Cabral, Lucía Mariana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; Argentina. Universidad de Extremadura; EspañaFil: Rodríguez, Alicia. Universidad de Extremadura; EspañaFil: Delgado, Josué. Universidad de Extremadura; EspañaFil: Patriarca, Andrea Rosana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentin

Use of the painDETECT tool in rheumatoid arthritis suggests neuropathic and sensitization components in pain reporting.

Rheumatoid arthritis (RA) is an inflammatory autoimmune condition typified by systemic inflammation targeted toward synovial joints. Inhibition of proinflammatory networks by disease-modifying antirheumatic drugs, eg, methotrexate and biologic therapies, including tumor necrosis factor-α inhibitors, often leads to suppression of disease activity observed at the clinical level. However, despite the era of widespread use of disease-modifying treatments, there remain significant groups of patients who continue to experience pain. Our study formulated a pain assessment tool in the arthritis clinic to assess feasibility of measurements including the visual analog scale (VAS) and painDETECT to assess multimodal features of pain in people with established RA (n=100). Clinical measures of disease activity (Disease Activity Score in 28 Joints [DAS28]) were also recorded. Our data showed that despite the majority of subjects on at least one disease-modifying agent, the majority of patients reported severe pain (54%) by VAS, despite well-controlled clinical disease, with mean DAS28 2.07±0.9. Using the painDETECT questionnaire, 67% of patients had unlikely neuropathic pain. A significant proportion of subjects (28%) had possible neuropathic pain and 5% had features of likely neuropathic pain by painDETECT scoring. We found a positive correlation between VAS and painDETECT (R (2)=0.757). Of note, the group who had likely or probable neuropathic pain also showed significantly increased pain reporting by VAS (P30) also had statistically higher proportions of pain reporting (VAS 89.0±0.7 mm) compared with subjects who had a normal body mass index (VAS 45.2±21.8 mm), P<0.05. Our findings suggest that multimodal features of pain perception exist in RA, including neuropathic and sensitization elements, perhaps explaining why a subgroup of people with RA continue to experience ongoing pain, despite their apparent suppression of inflammation

Exercise and Quality of Life Outcomes in a Patient with Stage 4 COPD

A 56-year-old female diagnosed with end stage COPD was referred to a rural based cardiac and pulmonary rehabilitation program. Medical history and initial baseline physical assessments were measured including resting vitals, height, weight, 6-minute walk test, and the HSQ-SF36® quality of life questionnaire. She was given a basic orientation to exercise equipment including Nu-Step® and five different band and dumbbell resistance exercises prescribed at 2 sets of 12 (RPE rating = 12 to 14). An exercise prescription for the exercise program three days per week was developed for approximately one hour at 2 to 3 METs with intermittent exercise on the Nu-Step® at a 4:1 ratio at 90% of estimated max level. After the initial assessment (August, 2014), she attended once, was absent for a 3 month period, then returned and was compliant with 8 sessions. She discontinued sessions at that point and was absent for two months. She came back for a third time on Feb. 2nd, 2015 after being hospitalized for 2 weeks secondary to pneumonia and bronchitis condition. She now uses two oxygen (2 liters) and assistive breathing techniques. Her exercise prescription was lowered to the initial prescription after all assessments were re-measured. As of Feb 2, she has attended 100 percent of the exercise sessions without incident or hospital re-admittance. Physical outcomes are contained in the table below. Quality of life measures will continue to be evaluated. August 2014 February 2015 Height (in): 62 62 Weight (lbs): 117 115 Blood Pressure (mmHg): 140/58 132/62 Heart Rate (bpm): 94 107 ECG: NSR NSR SaO2 (%): 95 (w/o O2) \u3c 88 (w/o O2); 96 (w/ O2) 6 minute walk distance (m): 218 25

Interacting temperature and water activity modulate production of Destruxin A by Metarhizium anisopliae on Galleria larvae-modified agar based media invitro

Destruxin A produced by some strains of entomopathogenic Metarhizium anisopliae is an important secondary metabolite which has been reported as a virulence factor. This study evaluated the effect of temperature and water activity (aw) on destruxin A (DA) production by two strains of M. anisopliae (V275 and Ma 275.86) cultured on Oxoid Technical Agar modified with homogenized insect larvae invitro. Only one of the strains (V275) produced DA on the substrate and there were significant variabilities in the amount of DA at different aw and temperature regimes. Concentrations of DA were further modulated by interactions of temperature and aw. The retention time for DA in the HPLC profile was 15.5 minutes and the highest peak was at 0.98 aw and 35°C while the lowest was at 0.96 aw and 35°C. The abiotic interactions that supported biomass production appeared different from what was required for production of DA. The optimal temperatures for biomass formation varied significantly with aw. At 0.995 aw and 25°C, highest biomass was produced while at relatively lower aw levels (0.98 and 0.96) the optimum temperature was 30 °C. There was a strong positive correlation (r = 0.455, n = 25, p = 0.023) between temperature and DA concentration

Impact of climate change environmental conditions on the resilience of different formulations of the biocontrol agent Candida sake CPA‐1 on grapes

Biocontrol agents have become componentsof integrated crop protection systemsfor controlling economically important fungal pathogens.Candida sakeCPA-1 is abiocontrol agent of fungal pathogens of fruits, both pre- and post-harvest. Whilethe efficacy of different formulations have been examined previously, few studieshave considered the resilience of different formulations under changing climaticconditions of elevated temperature, drought stress and increased atmospheric CO2.This study examined the effect of (a) temperature9RH9elevated CO2(400vs1000 ppm) on the temporal establishment and viability of two dry and one liquidC. sakeCPA-1 formulations on grape berry surfaces; (b) temperature stress (25vs35°C); and (c) elevated CO2levels. Results indicated that temperature, RH and CO2concentration influenced the establishment and viability of the formulations butthere was no significant difference between formulations. For the combined three-component factors, increased temperature (35°C) and lower RH (40%) reduced theviable populations on grapes. The interaction with elevated CO2improved theestablishment of viable populations of the formulations tested. Viable populationsgreater than Log 4 CFUs per g were recovered from the grape surfaces suggestingthat these had conserved resilience for control ofBotrytisrot in grapes.info:eu-repo/semantics/acceptedVersio

Predicted ecological niches and environmental resilience of different formulations of the biocontrol yeast Candida sake CPA-1 using the Bioscreen C

Environmental resilience of biocontrol microorganisms has been a major bottleneck in the development of effective formulations. Candida sake is an effective biocontrol agent (BCA) against Penicillium expansum, Botrytis cinerea or Rhizopus stolonifer, and different formulations of the BCA have been optimised recently. The objective of this study was to compare the relative tolerance of different dry and liquid formulations of the biocontrol yeast C. sake CPA-1 to interacting environmental conditions using the Bioscreen C. Initially, the use of this automated turbidimetric method was optimised for use with different formulations of the biocontrol yeast. The best growth curves were obtained for the C. sake CPA-1 strain when grown in a synthetic grape juice medium under continuous shaking and with an initial concentration of 105 CFUs ml−1. All the formulations showed a direct relationship between optical density values and yeast concentrations. Temperature (15–30 °C) and water activity (aw; 0.94–0.99) influenced the yeast resilience most profoundly, whereas the effect of pH (3–7) was minimal. In general, the liquid formulation grew faster in more interacting environmental conditions but only the yeast cells in the dry potato starch formulation could grow in some stress conditions. This rapid screening method can be used for effective identification of the resilience of different biocontrol formulations under interacting ecological abiotic conditions.info:eu-repo/semantics/acceptedVersio

Efficacy of fungal and bacterial antagonists for controlling growth, FUM1 gene expression and fumonisin B 1 production by Fusarium verticillioides on maize cobs of different ripening stages

This study was carried out to examine the efficacy of two biocontrol agents (Clonostachys rosea 016, BCA1; Gram-negative bacterium, BCA5) for control of FUM1 gene expression and fumonisin B1 (FB1) production by F. verticillioides FV1 on maize cobs of different ripening stages: R3, Milk (0.985 aw); R4, Dough (0.976 aw); R5, Dent (0.958 aw). Initially, temporal studies on FUM1 gene expression and FB1 production were performed on maize kernels for up to 14 days. This revealed that day 10 was optimum for both parameters, and was used in the biocontrol studies. Maize cobs were inoculated with 50:50 mixtures of the pathogen:antagonist inoculum and incubated in environmental chambers to maintain the natural aw conditions for ten days at 25 and 30 °C. The growth rates of F. verticillioides FV1, the relative expression of the FUM1 gene and FB1 production were quantified. It was found that, aw × temp had significant impacts on growth, FUM1 gene expression and FB1 production by F. verticillioides FV1 on maize cobs of different maturities. The fungal antagonist (BCA1) significantly reduced FB1 contamination on maize cobs by > 70% at 25 °C, and almost 60% at 30 °C regardless of maize ripening stage. For the bacterial antagonist (BCA5) however, FB1 levels on maize cobs were significantly decreased only in some treatments. These results suggest that efficacy of antagonists to control mycotoxin production in ripening maize cobs needs to take account of the ecophysiology of the pathogen and the antagonists, as well as the physiological status of the maize during silking to ensure effective control

Proof of concept: could snake venoms be a potential source of bioactive compounds for control of mould growth and mycotoxin production

© 2020 The Authors. This is an open access article under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.The objective was to screen 10 snake venoms for their efficacy to control growth and mycotoxin production by important mycotoxigenic fungi including Aspergillus flavus, Aspergillus westerdijkiae, Penicillium verrucosum, Fusarium graminearum and F. langsethiae. The Bioscreen C rapid assay system was used. The venoms from the Viperidae snake family delayed growth of some of the test fungi, especially F. graminearum and F. langsethiae and sometimes A. flavus. Some were also able to reduce mycotoxin production. The two most potent crude snake venoms (Naja nigricollis and N. siamensis; 41 and 43 fractions, respectively) were further fractionated and 83/84 of these fractions were able to reduce mycotoxin production by >90% in two of the mycotoxigenic fungi examined. This study suggests that there may be significant potential for the identification of novel fungistatic/fungicidal bioactive compounds as preservatives of raw and processed food commodities post-harvest from such snake venoms.Peer reviewedFinal Published versio

Predicted ecological niches and environmental resilience of different formulations of the biocontrol yeast Candida sake CPA-1 using the Bioscreen C

Environmental resilience of biocontrol microorganisms has been a major bottleneck in the development of effective formulations. Candida sake is an effective biocontrol agent (BCA) against Penicillium expansum, Botrytis cinerea or Rhizopus stolonifer, and different formulations of the BCA have been optimised recently. The objective of this study was to compare the relative tolerance of different dry and liquid formulations of the biocontrol yeast C. sake CPA-1 to interacting environmental conditions using the Bioscreen C. Initially, the use of this automated turbidimetric method was optimised for use with different formulations of the biocontrol yeast. The best growth curves were obtained for the C. sake CPA-1 strain when grown in a synthetic grape juice medium under continuous shaking and with an initial concentration of 105 CFUs ml−1. All the formulations showed a direct relationship between optical density values and yeast concentrations. Temperature (15–30 °C) and water activity (aw; 0.94–0.99) influenced the yeast resilience most profoundly, whereas the effect of pH (3–7) was minimal. In general, the liquid formulation grew faster in more interacting environmental conditions but only the yeast cells in the dry potato starch formulation could grow in some stress conditions. This rapid screening method can be used for effective identification of the resilience of different biocontrol formulations under interacting ecological abiotic conditions