Antimicrobial activity of spices essential oils and its effectiveness on mature biofilms of human pathogens.

The antibacterial activity of Pimpinella anisum L., Cinnamomum zeylanicum, Syzygium aromaticum, and Cuminum cyminum L. essential oils (EOs) against some common pathogenic microorganisms (Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 14990, Enterococcus faecalis ATCC 29212, Streptococcus pyogenes ATCC 1915, Escherichia coli ATCC 8739, Pseudomonas aeruginosa ATCC 27853, Aeromonas hydrophila ATCC 7966, Proteus mirabilis ATCC 10005, Klebsiella pneumoniae ATCC 13883, and Candida albicans ATCC 10231) and their biofilms was studied. The EOs inhibitory effects were evaluated by both Agar Well Diffusion assay and Minimum Inhibitory Concentration (MIC) determination. The most active EOs, cinnamon and cloves, were also tested on 18, 24, 48, 72 hours mature biofilms. Cinnamon and cloves exhibited the best results showing a significant activity against all the tested bacteria. Concerning biofilm, results suggest that Cinnamomum zeylanicum oil may be a useful approach to impair the biofilm produced by the tested Gram-negative bacteria. [Formula: see text].

Comparison of gluten peptides and potential prebiotic carbohydrates in old and modern Triticum turgidum ssp. genotypes.

Old wheat genotypes are perceived by consumers as healthier than modern ones. The release of gluten peptides with in vitro digestion and the content of potentially prebiotic carbohydrates (i.e. resistant fraction of starch and cell-wall associated dietary fiber) were evaluated in tetraploid wheats, namely 9 old and 3 modern Triticum turgidum ssp. genotypes. Simulated digestion of wholemeal flours yielded 152 major peptides, 59 of which were attributed a sequence. Principal component analysis revealed that peptide profiles were variable in old genotypes, unlike in modern ones. Digestion of old genotypes generally yielded peptides in greater concentration. In particular, 5 peptides of γ-gliadin, known to trigger the adaptive immune reaction, and two peptides of α-gliadin, known to be toxic to celiac patients, were particularly abundant in some old varieties. Resistant starch (RS) was negligible in modern genotypes (<0.6%), but it was remarkably abundant in some old varieties, reaching the highest value in Dauno III (8.5%, P < 0.05). Dauno III also presented the highest amount of soluble fiber (4.2%, P < 0.05). Pasta was made with an old and a modern genotype (Dauno III and PR22D89, respectively) with opposite RS content. Pasta making and cooking affected starch digestibility, overtaking differences between genotypes and yielding the same amount of RS for both the varieties (approx. 1.7%). The data herein presented suggest that the wholemeal flours of old tetraploid wheat genotypes could not boast particular claims associated to a lower exposure to gluten peptides and, if cooked, to a prebiotic potential.