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The phytochemical study of Bellis sylvestris has been carried out. This study led to the isolation of 28 secondary metabolites belonging to different classes. The structures of these compounds have been elucidated on the basis of extensive 2D-NMR spectroscopic analyses, including COSY, TOCSY, HSQC, CIGAR-HMBC, H2BC and HSQC-TOCSY, along with Q-TOF HRMS 2 analysis. Three of them, two megastimane derivatives and a glycoside of 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone, were reported for the first time. The compounds isolated from Bellis sylvestris were tested for their antimicrobial activity against some microorganisms associated with urinary tract infections ( Proteus mirabilis , Pseudomonas aeruginosa , Streptococcus aureus and Candida albicans ). The bacterial strains showed variable degrees of susceptibility to the compounds. Selected compounds were evaluated for their anti-biofilm properties against Pseudomonas aeruginosa and Candida albicans . Caffeic and rosmarinic acids were the once showing a higher reduction rate of biofilm formation. [ABSTRACT FROM AUTHOR]

Helicobacter pullorum is recognized as an emerging food-borne pathogen that may colonize the intestinal tract and the liver of avian species and humans causing several gastrointestinal and liver diseases. However, not all strains are reported to be capable of causing clinical disease, thus making poultry as reservoir for the zoonotic transmission of the infection through carcass contamination of broilers at slaughter. In poultry, the prevalence of this bacterium could be underestimated and the available data mainly refer to conventional rearing systems, whereas free-range and organic breedings have been poorly investigated. Therefore, this study was aimed to characterize the caecal microbiota community of free-range grown chickens and determine the presence and the relative abundance of H. pullorum by using NGS-based 16S rDNA sequencing. A total of 18 chickens reared for 56 d on a semi-extensive management system were euthanized at two time points: 9 birds at 28 d of age (before have access to outdoor; I = Indoor) and other 9 birds at 56 d of age (before slaughter; O = Outdoor). Cecal contents were collected for microbiota analyses. H. pullorum was detected in the cecum of 16/18 samples and its proportion in indoor was significantly higher than outdoor chickens (2.46 and 0.52%, respectively; P < 0.05), showing 78.8% of decrease with the outdoor access of the chickens. Therefore, it may be assumed that the potential for zoonotic infection is less likely. Moreover, H. pullorum was negatively correlated with 17 bacterial species as significantly more abundant in Outdoor microbial caecal communities. Among these, we highlighted the presence of Mucispirillium schaedleri and Oscillospira, already previously associated with a healthy gut and thus representing promising gut bacterial markers for host health. Our findings suggest that alternative production systems with outdoor access, may play a crucial role in the establishment of a healthy gut microbiota, which in turn might prevent colonization of harmful bacteria such as Helicobacter pullorum. [ABSTRACT FROM AUTHOR]

The occurrence of increased antibiotic resistance has reduced the availability of drugs effective in the control of infectious diseases, especially those caused by various combinations of bacteria and/or fungi that are often associated with poorer patient outcomes. In the hunt for novel antibiotics of interest to treat polymicrobial diseases, molecules bearing guanidine moieties have recently come to the fore in designing and optimizing antimicrobial agents. Due to their remarkable antibacterial and antifungal activities, labdane diterpenes are also attracting increasing interest in antimicrobial drug discovery. In this study, six different guanidines prenylated with labdanic fragments were synthesized and evaluated for their antimicrobial properties. Assays were carried out against both non-resistant and antibiotic-resistant bacteria strains, while their possible antifungal activities have been tested on the yeast Candida albicans. Two of the synthesized compounds, namely labdan-8,13(R)-epoxy-15-oyl guanidine and labdan-8,13(S)-epoxy-15-oyl guanidine, were finally selected as the best candidates for further developments in drug discovery, due to their antimicrobial effects on both Gram-negative and Gram-positive bacterial strains, their fungicide action, and their moderate toxicity in vivo on zebrafish embryos. The study also provides insights into the structure-activity relationships of the guanidine-functionalized labdane-type diterpenoids. [Display omitted] • Synthesis of acyl guanidines prenylated with labdanic diterpenoids. • Acylguanidines with a broad-spectrum antimicrobial activity. • Synergistic action of acylguanidines in combination with known antibiotics. • A short synthesis of natural ent -gomeric acids via a tandem HWE-oxa Michael reactions. [ABSTRACT FROM AUTHOR]

Abstract: Two new acylated styrylpyrones, one 5-methoxy-1(3H)-isobenzofuranone glucoside and a hydroxymethyl-orcinol derivative, along with sixteen known aromatic metabolites, including lignans, quinic acid derivatives low-molecular weight phenol glucosides, have been isolated from the methanol extract of Helichrysum italicum, a medicinal plant typical of the Mediterranean vegetation. The structures of these compounds have been elucidated on the basis of extensive 2D-NMR spectroscopic analyses, including COSY, TOCSY, HSQC, CIGAR-HMBC, H2BC and HSQC-TOCSY, along with Q-TOF HRMS2 analysis. Selected compounds were evaluated for their anti-biofilm properties against Pseudomonas aeruginosa. [Copyright &y& Elsevier]