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Background: Phytopathogenic fungi remain the main infectious agents in plants, causing severe damage to the environment and human health. Thus, to reduce the usage of synthetically derived fungicides and perform agricultural crop production, the search for new control strategies including plant extracts constitutes an eco-friendly and safe alternative. Objectives: This study aimed to quantify the phytochemical constituents of the three plant (Mentha pulegium L., Mentha spicata L., and Mentha longifolia L.) extracts and to screen their phytochemical composition including total phenolic (TPC), flavonoids (TFC) and condensed tannins contents (TCTC), and to evaluate their antioxidant activities. The efficacy of all mint extracts will be investigated against phytopathogenic fungal species. Materials and Methods: The three plant extracts were screened to assess their total phenolic, flavonoids, and condensed tannin contents using spectrophotometric assays. The antioxidant activities include 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric ion reducing antioxidant power (FRAP), and β-carotene assays. The antifungal activities were investigated on phytopathogenic species including Botrytis cinerea, Fusarium culmorum, Fusarium oxysporum, Aspergillus niger, Aspergillus flavus, and Trichoderma sp. Results: Quantitative analyses of phytochemical constituents of Mentha genus extracts revealed that both ethyl acetate (EtAc) and chloroformic (Chl) extracts are a rich source of phenols, flavonoids, and condensed tannins. Ethyl acetate extract of M. longifolia (EtAc L) displayed the highest content of phenols (69.9 ± 1.35 mg GAE/g DW) and flavonoids (53.26 ± 2.11 mg CE/g DW), while M. pulegium ethyl acetate extract (EtAc P) has the highest condensed tannins content (2.13 ± 0.4 mg CE/g DW). Moreover, the tested extracts exhibited potent antioxidant activities at low concentrations for EtAc L, followed by M. spicata (EtAc S), and EtAc P (IC50 = 35.76 ± 1.32 µg/mL for scavenging DPPH free radicals; EC50 527.96 ± 5.45 µg/mL for FRAP, and IC50 = 106.3 ± 3.75 µg/mL for β-carotene bleaching test). Finally, all tested extracts were able to inhibit the growth of several phytopathogenic micro-organisms on both agar and broth media. Conclusion: The Mentha extracts derived from the three mint species (i.e., L, P, and S) could be used for their antifungal activities to provide sustainable crop pest management. [ABSTRACT FROM AUTHOR]

Aerobic metabolism in plants results in the production of hydrogen peroxide (H2O2), a significant and comparatively stable non-radical reactive oxygen species (ROS). H2O2 is a signaling molecule that regulates particular physiological and biological processes (the cell cycle, photosynthesis, plant growth and development, and plant responses to environmental challenges) at low concentrations. Plants may experience oxidative stress and ultimately die from cell death if excess H2O2 builds up. Triticum dicoccoides, Triticum urartu, and Triticum spelta are different ancient wheat species that present different interesting characteristics, and their importance is becoming more and more clear. In fact, due to their interesting nutritive health, flavor, and nutritional values, as well as their resistance to different parasites, the cultivation of these species is increasingly important. Thus, it is important to understand the mechanisms of plant tolerance to different biotic and abiotic stresses by studying different stress-induced gene families such as catalases (CAT), which are important H2O2-metabolizing enzymes found in plants. Here, we identified seven CAT-encoding genes (TdCATs) in Triticum dicoccoides, four genes in Triticum urartu (TuCATs), and eight genes in Triticum spelta (TsCATs). The accuracy of the newly identified wheat CAT gene members in different wheat genomes is confirmed by the gene structures, phylogenetic relationships, protein domains, and subcellular location analyses discussed in this article. In fact, our analysis showed that the identified genes harbor the following two conserved domains: a catalase domain (pfam00199) and a catalase-related domain (pfam06628). Phylogenetic analyses showed that the identified wheat CAT proteins were present in an analogous form in durum wheat and bread wheat. Moreover, the identified CAT proteins were located essentially in the peroxisome, as revealed by in silico analyses. Interestingly, analyses of CAT promoters in those species revealed the presence of different cis elements related to plant development, maturation, and plant responses to different environmental stresses. According to RT-qPCR, Triticum CAT genes showed distinctive expression designs in the studied organs and in response to different treatments (salt, heat, cold, mannitol, and ABA). This study completed a thorough analysis of the CAT genes in Triticeae, which advances our knowledge of CAT genes and establishes a framework for further functional analyses of the wheat gene family. [ABSTRACT FROM AUTHOR]

Citrus, which belongs to the Rutaceae family, is a very widespread genus in the Mediterranean Basin. In Tunisia, various parts of these spontaneous or cultivated plants are used in common dishes or in traditional medicine. The purpose of this work was to investigate C. limon and C. paradisi essential oil (EO). The samples were studied for their chemical composition using SPME/MS, as well as their antibacterial and antifungal activities. Prothrombin time (PT) and activated partial thromboplastin time (aPTT) methods were used to evaluate the anticoagulant potentialities. The obtained results show that both essential oils are rich in monoterpenes hydrocarbons, whereby limonene is the main compound in C. paradisi EO (86.8%) and C. limon EO (60.6%). Moreover, C. paradisi EO contains β-pinene (13.3%), sabinene (2.2%) and α-pinene (2.1%). The antibacterial assay of the essential oils showed important bactericidal and fungicidal effects against all strains tested. In fact, the MICs values of C. limon EO ranged from 0.625 to 2.5 mg/mL against all Gram-positive and Gram-negative bacteria, and from 6.25 to 12.5 mg/mL for Candida spp. strains, while C. paradisi EO was more active against all bacteria with low MICs values ranging from 0.192 to 0.786 mg/mL, and about 1.5 mg/mL against Candida species. Both tested Citrus EOs exhibited interesting anticoagulant activities as compared to heparin. The molecular docking approach was used to study the binding affinity and molecular interactions of all identified compounds with active sites of cytidine deaminase from Klebsiella pneumoniae (PDB: 6K63) and the C (30) carotenoid dehydrosqualene synthase from Staphylococcus aureus (PDB: 2ZCQ). The obtained results show that limonene had the highest binding score of −4.6 kcal.mol−1 with 6K63 enzyme, and −6.7 kcal.mol−1 with 2ZCQ receptor. The ADME profiling of the major constituents confirmed their important pharmacokinetic and drug-like properties. Hence, the obtained results highlight the potential use of both C. limon and C. paradisi essential oils as sources of bioactive compounds with antibacterial, antifungal, and anti-coagulant activities. [ABSTRACT FROM AUTHOR]

Cancer is one of the major causes of death worldwide. The repercussions of conventional therapeutic approaches present a challenge in the delivery of new effective treatments. Thus, more attention is being awarded to natural products, mainly honey. Honey could be the basis for the development of new therapies for cancer patients. The aim of this study is to assess the phytochemical profiling, antioxidant, drug-likeness properties, and anticancer activity of Ziziphus honey (ZH) derived from the Hail region of Saudi Arabia. The phytochemical profiling using high resolution-liquid chromatography mass spectrometry (HR-LCMS) revealed 10 compounds belonging to several familial classes and one tripeptide. Potential antioxidant activity was noted as assessed by DPPH (IC50 0.670 mg/mL), ABTS (IC50 3.554 mg/mL), and β-carotene (IC50 > 5 mg/mL). The ZH exerted a notable cytotoxic effect in a dose-dependent manner against three cancer cell lines: lung (A549), breast (MCF-7), and colon (HCT-116), with respective IC50 values of 5.203%, 6.02%, and 7.257%. The drug-likeness investigation unveiled that most of the identified compounds meet Lipinski's rule. The molecular docking analysis revealed interesting antioxidant and anticancer activities for most targeted proteins and supported the in vitro findings. The Miraxanthin-III compound exhibited the most stabilized interaction. This study provides deeper insights on ZH as prominent source of bioactive compounds with potent antioxidant and anticancer effects. [ABSTRACT FROM AUTHOR]

Thymus musilii Velen. is a rare plant species cultivated in the Ha'il region (Saudi Arabia) under greenhouse conditions. In this work, we described, for the first time, the phytochemical composition, antimicrobial, antioxidant, anti-quorum sensing, and anticancer activities of T. musilii methanolic extract using both experimental and computational approaches. The obtained results showed the identification of eight small-like peptides and eighteen phyto-compounds by using high-resolution liquid chromatography–mass spectrometry (HR-LCMS) dominated mainly by compounds belonging to isoprenoid, fatty acyl, flavonoid, and alkaloid classes. The tested extracts exhibited high antifungal and antibacterial activity with the mean diameter of growth inhibition zones ranging from 12.33 ± 0.57 mm (Pseudomonas aeruginosa ATCC 27853) to 29.33 ± 1.15 mm (Candida albicans ATCC 10231). Low minimal inhibitory concentrations were recorded for the tested micro-organisms ranging from 0.781 mg/mL to 12.5 mg/mL. While higher doses were necessary to completely kill all tested bacterial and fungal strains. Thyme extract was able to scavenge DPPH•, ABTS•+, β-carotene, and FRAP free radicals, and the IC50 values were 0.077 ± 0.0015 mg/mL, 0.040 ± 0.011 mg/mL, 0.287 ± 0.012 mg/mL, and 0.106 ± 0.007 mg/mL, respectively. The highest percentage of swarming and swimming inhibition was recorded at 100 µg/mL with 39.73 ± 1.5% and 25.18 ± 1%, respectively. The highest percentage of biofilm inhibition was recorded at 10 mg/mL for S. typhimurium ATCC 14028 (53.96 ± 4.21%) and L. monocytogenes ATCC 7644 (49.54 ± 4.5 mg/mL). The in silico docking study revealed that the observed antimicrobial, antioxidant, and anticancer activities of the constituent compounds of T. musilii are thermodynamically feasible, notably, such as those of the tripeptides (Asn-Met-His, His-Cys-Asn, and Phe-His-Gln), isoprenoids (10-Hydroxyloganin), and diterpene glycosides (4-Ketoretinoic acid glucuronide). [ABSTRACT FROM AUTHOR]

Biosurfactants have gained more attention in the past decade as possible medical resources. They are useful therapeutic agents against many infections because of their antibacterial, antifungal, and antiviral properties. Additionally, the anti-adherent activities of these compounds counter to a number of pathogens suggest that they could be useful as an anti-adherent coating for medical inserts, helping to prevent infections in hospitals without the use of chemicals. This study aims to investigate the antiadhesive activities of biosurfactants extracted from Lactobacillus brevis and Bacillus sp. against seven clinical pathogens. Biosurfactants at different concentrations were applied to polystyrene surfaces, and then the attachment of pathogenic strains was evaluated. The adhesion of microbes to n-hexadecane was also studied. As a result, the bacterial strains with 50 mg/ml of Lactobacillus brevis biosurfactant displayed a 69–73% reduction in adhesion. In contrast to the first biosurfactant, a biosurfactant extracted from Bacillus sp. significantly reduced bacterial attachment at all concentrations studied, although to a lesser extent. As the concentration was increased in surface conditioning tests, the anti-adhesive activity increased, showing the significance of considering this. In summary, both biosurfactants demonstrated excellent potential as anti-adhesive compounds that can prevent microbial contamination. Our findings provided evidence that biosurfactants could be used in medical applications. [ABSTRACT FROM AUTHOR]

A revival interest has been given to natural products as sources of phytocompounds to be used as alternative treatment against infectious diseases. In this context, we aimed to investigate the antimicrobial potential of Ziziphus honey (ZH) against twelve clinical bacterial strains and several yeasts and molds using in vitro and computational approaches. The well-diffusion assay revealed that ZH was able to induce growth inhibition of most Gram-positive and Gram-negative bacteria. The high mean growth inhibition zone (mGIZ) was recorded in E. coli (Clinical strain, 217), S. aureus followed by E. coli ATCC 10536 (mGIZ values: 41.00 ± 1 mm, 40.67 ± 0.57 mm, and 34.67 ± 0.57 mm, respectively). The minimal bactericidal concentrations (MBCs) and minimal fungicidal concentration values (MFCs) from approximately 266.33 mg/mL to over 532.65 mg/mL. Molecular docking results revealed that the identified compounds maltose, 2-furoic acid, isopropyl ester, 2,4-imidazolidinedione, 5-(2-methylpropyl)-(S)- and 3,4,5-trihydroxytoluene, S-Methyl-L-Cysteine, 2-Furancarboxylic acid, L-Valine-N-ethoxycarbonyl, Hexanoic acid, 3,5,5-trimethyl-, Methyl-beta-D-thiogalactoside, gamma-Sitosterol, d-Mannose, 4-O-Methylmannose, 2,4-Imidazolidinedione, 5-(2-methylpropyl)- (S) were found to have good affinity for targeted receptor, respectively. Through a 100-ns dynamic simulation research, binding interactions and stability between promising phytochemicals and the active residues of the studied enzymes were confirmed. The ADMET profiling of all identified compounds revealed that most of them could be qualified as biologically active with good absorption and permeation. Overall, the results highlighted the efficiency of ZH against the tested clinical pathogenic strains. The antimicrobial potential and the potency displayed by the identified compounds could imply their further pharmacological applications.Communicated by Ramaswamy H. Sarma.

Aerobic metabolism in plants results in the production of hydrogen peroxide (H 2 O 2 ), a significant and comparatively stable non-radical reactive oxygen species (ROS). H 2 O 2 is a signaling molecule that regulates particular physiological and biological processes (the cell cycle, photosynthesis, plant growth and development, and plant responses to environmental challenges) at low concentrations. Plants may experience oxidative stress and ultimately die from cell death if excess H 2 O 2 builds up. Triticum dicoccoides , Triticum urartu, and Triticum spelta are different ancient wheat species that present different interesting characteristics, and their importance is becoming more and more clear. In fact, due to their interesting nutritive health, flavor, and nutritional values, as well as their resistance to different parasites, the cultivation of these species is increasingly important. Thus, it is important to understand the mechanisms of plant tolerance to different biotic and abiotic stresses by studying different stress-induced gene families such as catalases (CAT), which are important H 2 O 2 -metabolizing enzymes found in plants. Here, we identified seven CAT -encoding genes ( TdCATs ) in Triticum dicoccoides , four genes in Triticum urartu ( TuCATs ), and eight genes in Triticum spelta ( TsCATs ). The accuracy of the newly identified wheat CAT gene members in different wheat genomes is confirmed by the gene structures, phylogenetic relationships, protein domains, and subcellular location analyses discussed in this article. In fact, our analysis showed that the identified genes harbor the following two conserved domains: a catalase domain (pfam00199) and a catalase-related domain (pfam06628). Phylogenetic analyses showed that the identified wheat CAT proteins were present in an analogous form in durum wheat and bread wheat. Moreover, the identified CAT proteins were located essentially in the peroxisome, as revealed by in silico analyses. Interestingly, analyses of CAT promoters in those species revealed the presence of different cis elements related to plant development, maturation, and plant responses to different environmental stresses. According to RT-qPCR, Triticum CAT genes showed distinctive expression designs in the studied organs and in response to different treatments (salt, heat, cold, mannitol, and ABA). This study completed a thorough analysis of the CAT genes in Triticeae , which advances our knowledge of CAT genes and establishes a framework for further functional analyses of the wheat gene family.