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Background: Ochratoxin A (OTA) and Aflatoxin B1 (AFB1) are toxic secondary metabolites produced by certain mold species. In this primarily survey, we examined the OTA and AFB1 contamination of pearl millet grains distributed in Tunisia. Methods: Twenty-five pearl millet (Pennisetum glaucum L.) samples from different regions of Tunisia were analyzed by High Performance Liquid Chromatography coupled with fluorescence detector in order to evaluate the contamination with of AFB1 and OTA. Statistical tests were performed with XLSTAT 2018. Results: AFB1 and OTA were detected in 32 and 28% millet samples, respectively. Mean amounts of these mycotoxins in the contaminated samples were of 24.54±17.54 µg/kg for OTA and 22.72±23.09 µg/kg for AFB1. Approximately, 28 and 24% of analyzed samples were found above the European Union limits for AFB1 and OTA, respectively. The estimated daily intake of OTA and AFB1 were 3.76 and 3.89 ng/kg b.w. per day, respectively. No significantly (p>0.05) difference in OTA and AFB1 contamination rate was found between samples taken from different regions. Conclusion: Consumption of millet in Tunisia might be an important contributing factor to the risk of dietary exposure to OTA and AFB1. [ABSTRACT FROM AUTHOR]

In order to search for new chemotypes and to carry out a comparative study with the literature, the current study investigated the chemical composition of the essential oil of the flowers of Daucus carota (L.) ssp. carota using gas chromatography coupled with mass spectrometry (GC-MS). Moreover, the antimicrobial and insecticidal potentials of essential oil were studied. Hydrodistillation was used to extract the essential oil. Due to the immiscibility of essential oils in water and, therefore, in the culture medium, emulsification was carried out using a 0.2 % agar solution to promote germ/composite contact. Fumigation with the oil phase of the essential oil was carried out in airtight and transparent plastic boxes, with a capacity of 1 L as an exposure chamber to test the lightness of essential oils against adults of Sitophilus oryzae (L.). In each box, five Petri dishes were placed. Each replicate consisted of five adults of S. oryzae (L.). The essential oils were spread on Wathman filter paper and placed inside the exposure chamber. Mortality control was carried out by counting insect deaths from the first day of treatment until the death of all individuals. α-Pinene (22.2 %) was the major compound in the essential oil of the oil phase of D. carota (L.) ssp. carota followed by β-asarone (15.1 %), sabinene (12.4 %), and α-himachalene (10.1 %), as well as the crystallized phase containing β-asarone. In terms of antimicrobial activity, the essential oils showed significant inhibition of the six bacteria and seven molds studied at a concentration of 0.45 mg/mL. The essential oils were found to be highly effective against S. oryzae (L.). This approach can help reduce the amount of synthetic antibiotics applied and, therefore, decrease the negative impact of artificial agents, such as residues, resistance, and environmental pollution., (© 2024 Walter de Gruyter GmbH, Berlin/Boston.)

The essential oil and the aqueous and ethanolic extracts obtained from the aerial parts of Pelargonium graveolens cultivated in Morocco were studied for their antioxidant and insecticidal activity against rice weevils ( Sitophylus oryzae ). The total phenolic content of the extracts was determined by a spectrophotometric method and the phenolic compounds were extensively characterized by HPLC-PDA/ESI-MS. To evaluate antioxidant potential, three in vitro assays were used. In the DPPH test, the ethanolic extract was the most active, followed by the aqueous extract and the essential oil. In the reducing power assay, excellent activity was highlighted for both extracts, while in the Fe 2+ chelating activity assay, weak activity was observed for both the essential oil and the ethanolic extract and no activity for the aqueous extract. Concerning insecticide activity, the toxicity of the essential oil and the extracts was tested against rice weevils; the lethal concentrations LC 50 and LC 99 were determined, as well as the lethal time required for the death of 50% (LT 50 ) and 99% (LT 99 ) of the weevils. The essential oil had the highest activity; 100% mortality of S. oryzae was observed around 5, 9, and 8 days for the essential oil and the aqueous and ethanolic extracts, respectively.

Under stress or in optimum conditions, plants foster a specific guild of symbiotic microbes to strengthen pivotal functions including metabolic regulation. Despite that the role of the plant genotype in microbial selection is well documented, the potential of this genotype-specific microbial assembly in maintaining the host homeostasis remains insufficiently investigated. In this study, we aimed to assess the specificity of the foliar metabolic response of contrasting olive genotypes to microbial inoculation with wet-adapted consortia of plant-growth-promoting rhizobacteria (PGPR), to see if previously inoculated plants with indigenous or exogenous microbes would display any change in their leaf metabolome once being subjected to drought stress. Two Tunisian elite varieties, Chetoui (drought-sensitive) and Chemleli (drought-tolerant), were tested under controlled and stressed conditions. Leaf samples were analyzed by gas chromatography-mass spectrometry (GC-TOFMS) to identify untargeted metabolites. Root and soil samples were used to extract microbial genomic DNA destined for bacterial community profiling using 16S rRNA amplicon sequencing. Respectively, the score plot analysis, cluster analysis, heat map, Venn diagrams, and Krona charts were applied to metabolic and microbial data. Results demonstrated dynamic changes in the leaf metabolome of the Chetoui variety in both stress and inoculation conditions. Under the optimum state, the PGPR consortia induced noteworthy alterations in metabolic patterns of the sensitive variety, aligning with the phytochemistry observed in drought-tolerant cultivars. These variations involved fatty acids, tocopherols, phenols, methoxyphenols, stilbenoids, triterpenes, and sugars. On the other hand, the Chemleli variety displaying comparable metabolic profiles appeared unaffected by stress and inoculation probably owing to its tolerance capacity. The distribution of microbial species among treatments was distinctly uneven. The tested seedlings followed variety-specific strategies in selecting beneficial soil bacteria to alleviate stress. A highly abundant species of the wet-adapted inoculum was detected only under optimum conditions for both cultivars, which makes the moisture history of the plant genotype a selective driver shaping microbial community and thereby a useful tool to predict microbial activity in large ecosystems.

Introduction: Periodontitis, as a chronic, multifactorial inflammatory disease, has complex relationships with other diseases and ultimately with well-being. The aim of this cross-sectional study was to investigate the association between self-report periodontitis, as measured with the recently developed and validated modified Periodontal Screening Score (mPESS), and oral health-related quality of life (OHRQol) in a large population-based sample derived from the French NutriNet-Santé e-cohort., Methods: The sample was composed of 32,714 adults (75.5% women) with a mean age of 48.8 ± 13.9 years. Periodontitis was assessed based on age, smoking, and oral health status data obtained in 2011-2012, which allowed calculating the mPESS. An mPESS ≥ 5 was used to identify individuals at risk of severe periodontitis (main exposure). OHRQoL was measured with the Oral Health Impact Profile (OHIP-14) (main outcome) and the total score was dichotomized for analysis. Multivariable logistic regression analyses, considering physical health status, dietary and lifestyle confounding variables, were performed., Results: Overall, 6407 participants (19.6%) were at a high risk of severe periodontitis. A total of 7383 participants (22.6%) presented a relatively poor OHRQoL (OHIP-14 > 8, highest quartile). In the multivariable model, each of the following variables was independently and significantly associated with lower OHRQoL: older age (50-64 years), female sex, obesity, snacking between meals, frequent consumption of soft drinks and sweets/chocolate, risk of severe periodontitis, and having < 20 natural teeth were significantly. An mPESS ≥ 5 showed the highest odds for relatively poor OHRQoL (OR = 3.45; 95% CI 3.21-3.72)., Conclusion: The results support the association between periodontitis and OHRQoL in non-clinical samples. The use of mPESS could be tested in future prevention programs aiming at improving OHRQoL., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Introduction: Most of elite cultivated grapevine varieties ( Vitis vinifera L.), conventionally grafted on rootstocks, are becoming more and more affected by climate changes, such as increase of salinity. Therefore, we revisited the valuable genetic resources of wild grapevines ( V. sylvestris ) to elaborate strategies for a sustainable viticulture., Methods: Here, we compared physiological and biochemical responses of two salt-tolerant species: a wild grapevine genotype "Tebaba" from our previous studies and the conventional rootstock "1103 Paulsen". Interestingly, our physio-biochemical results showed that under 150mM NaCl, "Tebaba" maintains higher leaf osmotic potential, lower Na+/K+ ratio and a significant peaked increase of polyphenol content at the first 8h of salinity stress. This behavior allowed to hypothesis a drastic repatterning of metabolism in "Tebaba's" roots following a biphasic response. In order to deepen our understanding on the "Tebaba" salt tolerance mechanism, we investigated a time-dependent transcriptomic analysis covering three sampling times, 8h, 24h and 48h., Results: The dynamic analysis indicated that "Tebaba" root cells detect and respond on a large scale within 8h to an accumulation of ROS by enhancing a translational reprogramming process and inducing the transcripts of glycolytic metabolism and flavonoids biosynthesis as a predominate non-enzymatic scavenging process. Afterwards, there is a transition to a largely gluconeogenic stage followed by a combined response mechanism based on cell wall remodeling and lignin biosynthesis with an efficient osmoregulation between 24 and 48 h., Discussion: This investigation explored for the first time in depth the established cross-talk between the physiological, biochemical and transcriptional regulators contributing to propose a hypothetical model of the dynamic salt mechanism tolerance of wild grapevines. In summary, these findings allowed further understanding of the genetic regulation mechanism of salt-tolerance in V. sylvestris and identified specific candidate genes valuable for appropriate breeding strategies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Daldoul, Hanzouli, Hamdi, Chenenaoui, Wetzel, Nick, Mliki and Gargouri.)

In this paper, we assessed the ability of two strains of Saccharomyces cerevisiae, in viable and dead forms, to remove ochratoxin A (OTA) from an artificially contaminated synthetic grape juice medium (SGM) (10 µg OTA/L) and a naturally contaminated grape juice (6.64 µg OTA/L). The first strain, named Levulin FB, is a commercial yeast used in making wine. The second, named SC5, is an autochthonous strain isolated from table grapes. OTA concentrations in juices before and after their contact with yeast cells were assessed. A significant decrease in OTA level (p < 0.05) in the SGM medium and in the natural grape juice was observed after 1 h of adding yeast cells (20 g/L) in viable and heat-treated forms. It was inferred that the dead forms of the two strains were more able to eliminate OTA than their viable forms in both media. This study demonstrates the potential application of an autochthonous yeast for the natural decontamination of grape juice from fungal toxins.

The adsorption of sulfur-containing compounds from fuels on polymer nanocomposite adsorbents modified with carbon-based materials was investigated. This work reports the removal of benzothiophene from the model liquid fuel using a novel adsorbent prepared by nanopoly (4,4'-methylenedianiline)-graphene oxide (NPMDA/GO) composite. The adsorbent was successfully synthesized with the in situ electrochemical method and characterized using thermal gravimetric analysis (TGA), field-scattering scanning electron microscopy (FE-SEM), transient electron microscopy (TEM), X-ray diffraction analysis (XRD), and Fourier transform infrared (FTIR). The results showed that the presence of graphene oxide (GO) nanosheets in NPMDA/GO composite adsorbent due to its high tendency to sulfur would increase the adsorption of benzothiophene compared to unmodified nanopoly (4,4'-methylenedianiline) (NPMDA). The π&#95;complexation, oxygenated organic functional groups, and layered sheets of graphene oxide improve adsorption capacity for desulfurization. The NPMDA/GO composite presented maximum efficiency (63.33%) at 30 mg/L initial concentration, 120 mg adsorbent dose, and 120 min contact time at 25 °C. Furthermore, the adsorbent shows an almost good reusability after four cycles (67.12 mg/g sulfur absorption capacity). Pseudo-second-order model (R 2  = 0.9975) and the Freundlich isotherm (R 2  = 0.8813) were used to describe the adsorption process. Findings confirm that NPMDA/GO composite can be applicable for removal of benzothiophene from liquid fuels., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Recent evidence suggests that dietary habits influence the development and severity of periodontitis. The present cross-sectional study evaluated the association between different types and quantity of alcoholic beverage consumption (alone and interacting with smoking) and the probability to suffer from severe periodontitis in the French e-cohort NutriNet-Santé., Methods: The study population consisted of 35,390 adults (mean age: 49.04 ± 13.94 years), who filled oral health questionnaires and completed at least three non-consecutive 24-hour dietary records. Data on type and frequency of alcoholic beverage consumption were obtained from a semi-quantitative self-reported alcohol frequency questionnaire; the daily quantity (g/day) was estimated from the 24-hour dietary records. The probability of severe periodontitis (main dependent variable) was assessed by calculating the modified periodontal screening score (mPESS) from selected questions., Results: A total of 7263 individuals (20.5%) presented a high probability of suffering from severe periodontitis (high-mPESS). After adjusting for confounding factors, the frequency of alcoholic beverage consumption was significantly higher among high-mPESS group than their low-mPESS counterparts, especially for hard liquor/spirits (1.9 ± 1.4 days/week for high-PESS versus 1.6 ± 1.1 days/week the low-PESS [P < 0.0001]). The mean daily quantity of ethanol was also higher in high-mPESS versus low-mPESS individuals (11.2 ± 15.6 versus 7.9 ± 12.3 g/day; P = 0.011). A stronger association with self-report severe periodontitis was noted when alcohol consumption exceeding > 20 g/day for women and > 30 g/day for men was combined with smoking habit (OR = 7.30 [95% CI: 6.1-8.73])., Conclusion: The present results support an association between alcoholic beverage consumption and self-report severe periodontitis, particularly when it is associated with current smoking., (© 2020 American Academy of Periodontology.)

Background: Baloxavir is a cap-dependent inhibitor of the polymerase acid (PA) protein of influenza viruses. While appearing virologically superior to oseltamivir, baloxavir exhibits a low barrier of resistance. We sought to assess the impact of the common baloxavir-resistant I38T PA substitution on in vitro properties and virulence., Methods: Influenza A/Quebec/144147/2009 (H1N1)pdm09 and A/Switzerland/9715293/2013 (H3N2) recombinant viruses and their I38T PA mutants were compared in single and competitive infection experiments in ST6GalI-MDCK cells and C57/BL6 mice. Virus titers in cell culture supernatants and lung homogenates were determined by virus yield assays. Ratios of wild-type (WT) and I38T mutant were assessed by digital RT-PCR., Results: I38T substitution did not alter the replication kinetics of A(H1N1)pdm09 and A(H3N2) viruses. In competition experiments, a 50%:50% mixture evolved to 70%:30% (WT/mutant) for A(H1N1) and 88%:12% for A(H3N2) viruses after a single cell passage. The I38T substitution remained stable after 4 passages in vitro. In mice, the WT and its I38T mutant induced similar weight loss with comparable lung titers in both viral subtypes. The mutant virus tended to predominate over the WT in mouse competition experiments., Conclusion: The fitness of baloxavir-resistant I38T PA mutants appears relatively unaltered in seasonal subtypes warranting surveillance for its dissemination., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

The mouse is the most widely used animal model for influenza virus research. However, the susceptibility of mice to seasonal influenza virus depends on the strain of mouse and on the strain of the influenza virus. Seasonal A/H3N2 influenza viruses do not replicate well in mice and therefore they need to be adapted to this animal model. In this study, we generated a mouse-adapted A/H3N2 virus (A/Switzerland/9715293/2013 [MA-H3N2]) by serial passaging in mouse lungs that exhibited greater virulence compared to the wild-type virus (P0-H3N2). Seven mutations were found in the genome of MA-H3N2: PA(K615E), NP(G384R), NA(G320E) and HA(N122D, N144E, N246K, and A304T). Using reverse genetics, two synergistically acting genes were found as determinants of the pathogenicity in mice. First, the HA substitutions were shown to enhanced viral replication in vitro and, second, the PA-K615E substitution increased polymerase activity, although did not alter virus replication in vitro or in mice. Notably, single mutations had only limited effects on virulence in vitro. In conclusion, a co-contribution of HA and PA mutations resulted in a lethal mouse model of seasonal A/H3N2 virus. Such adapted virus is an excellent tool for evaluation of novel drugs or vaccines and for study of influenza pathogenesis.