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The genus Thymus L., belonging to the Lamiaceae family, contains about 220 species with a distribution that mainly extends in Europe, northwest Africa, Ethiopia, Asia, and southern Greenland. Due to their excellent biological properties, fresh and/or dried leaves and aerial parts of several Thymus ssp. have been utilized in the traditional medicine of many countries. To evaluate not only the chemical aspects but also the biological properties, the essential oils (EOs), obtained from the pre-flowering and flowering aerial parts of Thymus richardii subsp. nitidus (Guss.) Jalas, endemic to Marettimo Island (Sicily, Italy), were investigated. The chemical composition of the EOs, obtained by classical hydrodistillation and GC-MS and GC-FID analyses, showed the occurrence of similar amounts of monoterpene hydrocarbons, oxygenated monoterpenes, and sesquiterpene hydrocarbons. The main constituents of the pre-flowering oil were β-bisabolene (28.54%), p-cymene (24.45%), and thymol methyl ether (15.90%). The EO obtained from the flowering aerial parts showed as principal metabolites β-bisabolene (17.91%), thymol (16.26%), and limonene (15.59%). The EO of the flowering aerial parts, and its main pure constituents, β-bisabolene, thymol, limonene, p-cymene, and thymol methyl ether were investigated for their antimicrobial activity against oral pathogens and for their antibiofilm and antioxidant properties.

Polyethylene (PE) is high molecular weight synthetic polymer, very hydrofobic and hardly biodegradable. To increase polyethylene bio-degradability it is very important to find microorganisms that improve the PE hydrophilic level and/or reduce the length of its polymeric chain by oxidation. In this study, we isolated Cladosporium halotolerans, a fungal species, from the gastric system of Galleria mellonella larvae. Here, we show that C. halotolerans grows in the presence of PE polymer, it is able to interact with plastic material through its hyphae and secretes enzymes involved in PE degradation.

Daucus is a genus of economically important plants belonging to Apiaceae family spread in temperate regions. Species of this genus are used as food and several biological properties have reported. The chemical composition of the essential oils from different organs (roots, stems and flowers) of Daucus carota subsp. maximus, a species not previously investigated, was analyzed by GC-MS. Our results showed the presence of β-phellandrene as the most abundant component of stems and flowers and of γ-terpinene as a major compound of the oil from the roots. Flower essential oil caused a greater increase in the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in polymorphonuclear leukocytes (PMN) cells compared to stem and root essential oils. The antimicrobial activity of the flower and stem oil were more effective, compared to root oil, against Escherichia coli and Staphylococcus aureus.

In this work, the essential oil of the aerial parts of a not previously investigated accession of

In this work, the essential oil of the aerial parts of a not previously investigated accession of Prangos trifida (Mill.) Herrnst. & Heyn (Apiaceae), collected in Northern Italy, was analysed by GC/MS. Twenty-five compounds were identified, accounting for 91.30% of the total oil, which is characterised by a high content of monoterpene hydrocarbons (71.26%). The main constituents of the essential oil were cis-beta-ocimene (18.12%), alpha-phellandrene (12.14%), sylvestrene (11.32%), p-mentha-1,3,8-triene (9.56%) and alpha-pinene (8.85%). The essential oil of P. trifida showed a good antimicrobial activity directed above all against Gram-positive bacteria, and had an interesting antioxidant activity, thus making it an excellent candidate for future cosmetic and pharmaceutical applications.

The Stachys L. genus has been used in traditional medicine to treat skin inflammations, stomach disorders, and stress. The aim of this study was to investigate the chemical profile and biological activity of the methanolic extract of Stachys spreitzenhoferi Heldr. (Lamiaceae) aerial parts, collected on the island of Kythira, South Greece. The analysis by liquid chromatography coupled with electrospray ionization and high-resolution mass spectrometry [LC-(-)ESI/HRMSn] of the methanol extract revealed the occurrence of thirty-six compounds - flavonoids, phenylethanoid glycosides, iridoids, quinic acid derivatives, aliphatic alcohol glycosides, and oligosaccharides - highlighting the substantial presence, as main peaks, of the iridoid melittoside (2) along with flavonoid compounds such as 4'-O-methylisoscutellarein mono-acetyl-diglycoside/chrysoeriol mono-acetyl-diglycoside (24), trimethoxy- (35) and tetramethoxyflavones (36). This extract was tested for its antimicrobial properties against Gram-positive and negative pathogenic strains. The extract was not active against Gram-negative bacteria tested, but it possessed a good dose-dependent antimicrobial activity towards S. aureus (MIC: 1.0mg/mL) and L. monocytogenes (MIC: 1.0mg/mL) Gram-(+) strains. Furthermore, this extract has been tested for its possible antioxidant activity in vitro. In particular, it has been shown that these molecules cause a decrease in DPPH, ABTS, and H2O2 radicals. The extract of S. spreitzenhoferi exhibited anti-DPPH activity (IC50: 0.17mg/mL), anti-H2O2 activity (IC50: 0.125mg/mL), and promising antiradical effect with an IC50 value of 0.18mg/mL for anti-ABTS activity. S. spreitzenhoferi extract caused a decrease in ROS (at the concentration of 200μg/mL) and an increase in the activity of the antioxidant enzymes SOD, CAT, and GPX in OZ-stimulated PMNs. Furthermore, it exhibited antiproliferative activity against acute myeloid leukemia (U937cell), causing 50% of cell death at the 0.75mg/mL.

Anthemis secundiramea is a perennial herb native widespread throughout the Mediterranean basin. The oil obtained from the flowers of this plant has antimicrobial properties against gram-positive and -negative bacteria, and inhibits the biofilm formation. The extract of A. secundiramea also has antioxidant activity&mdash, increasing the activity of different enzymes (SOD, CAT, and GPx). Surprisingly, in the oil extracted from the flowers, there is a single molecule, called (+)-(E)-chrysanthenyl acetate: This makes the A. secundiramea flowers extract extremely interesting for future topical, cosmetic, and nutraceutical applications.

International audience; The evolution of antibacterial resistance has arisen as the main downside in fighting bacterial infections pushing researchers to develop novel, more potent and multimodal alternative drugs.Silver and its complexes have long been used as antimicrobial agents in medicine due to the lack of silver resistance and the effectiveness at low concentration as well as to their low toxicities compared to the most commonly used antibiotics. N-Heterocyclic Carbenes (NHCs) have been extensively employed to coordinate transition metals mainly for catalytic chemistry. However, more recently, NHC ligands have been applied as carrier molecules for metals in anticancer applications. In the present study we selected from literature two NHC-carbene based on acridinescaffoldand detailed nonclassicalpyrazole derived mono NHC-Ag neutral and bis NHC-Ag cationic complexes. Their inhibitor effect on bacterial strains Gram-negative and positivewas evaluated. Imidazolium NHC silver complex containing the acridine chromophore showed effectiveness at extremely low MIC values. Although pyrazole NHC silver complexes are less active than the acridine NHC-silver, they represent the first example of this class of compounds with antimicrobial properties. Moreover all complexesare not toxic and they show not significant activity againstmammalian cells (Hek lines) after 4 and 24 h. Based on our experimental evidence, we are confident that this promising class of complexes could represent a valuable starting point for developing candidates for the treatment of bacterial infections, delivering great effectiveness and avoiding the development of resistance mechanisms.

Acca sellowiana is an evergreen plant that produces edible fruit whit high nutritional properties, and also contains clinically relevant bioactive compounds, including polyphenols and essential oils. Numerous biological activities were demonstrated for A. sellowiana fruits: antifungal and antitumoral and anti-oxidant. It was also showed a strong antibacterial activity against Gram-positive and Gram-negative bacteria. Fruit are generally considered recalcitrant plant tissues for the difficulty to obtain high quality protein due to a low protein content and the presence of interfering substances. For this reason, the objective of the present work was obtain high quantity of protein extract, to determine the location in the fruit of the molecules responsible for the antibacterial activity, separate them according to molecular weight, test their thermo resistance, study the timing of action, isolate the protein fraction having activity and hypothesise a mechanism of action directed against bacterial membranes.

Hybrid Melanin-TiO

Hybrid Melanin-TiO2 nanoparticles are promising bioinspired antibacterial agents for biomedical coatings and food-packaging fields. However, due to a very low colloidal stability, they showed a high tendency to self-aggregate and rapidly precipitate, making not easy their use in aqueous medium to produce homogeneous antimicrobial coatings or nanocomposites. A valid strategy to improve their dispersion is the combination with a hydrophilic water-soluble polymer such as poly-vinyl-alcohol (PVA), which is a good choice to improve the colloidal stability of nanoparticles and to modulate their agglomeration. In this work, we propose an in-situ synthetic approach based on the hydrothermal route, by which the hybrid Melanin-TiO2 nanoparticles were prepared starting from the inorganic and organic precursors in the presence of PVA. Combined approach of TEM, XRD, TG/DSC, EPR and DLS techniques allows for assessing the PVA role in the formation of hybrids and on their morphological features as well as colloidal stability and aqueous dispersion. Antibacterial tests demonstrated the biocide activity of PVA/Melanin-TiO2 nanoparticles against Escherichia coli bacterial cultures, which resulted partially influenced by the PVA content. This study provides key information on the mutual influence of organic/inorganic components on the functional properties of the final hybrid nanocomposites, contributing to define a much more far-reaching implementation in the synthesis of bioinspired polymer-based nanocomposites.

Nature has provided a valuable source of inspiration for developing high performance multifunctional materials. Particularly, catechol-containing amino acid l-3,4-dihydroxyphenylalanine (l-DOPA) has aroused the interest to design hybrid multifunctional materials with superior adhesive ability. DOPA oxidative polymerization mediated by either melanogenic enzymes or an alkaline environment involving catechol intermolecular cross-linking, ultimately leads to melanin oligomers. Recently, relevant studies disclosed the ability of Ti-based nanostructures to tune melanin&rsquo, s supramolecular structure during its formation, starting from melanogenic precursors, thus improving both antioxidant and antimicrobial properties. In this work, we propose a novel biomimetic approach to design hybrid DOPA melanin-like nanostructures through a hydrothermal synthesis opportunely modified by using citric acid to control hydrolysis and condensation reactions of titanium alkoxide precursors. UV-Vis and Electron paramagnetic resonance (EPR) spectroscopic evidences highlighted the key role of citrate&ndash, Ti(IV) and DOPA&ndash, Ti(IV) complexes in controlling DOPA polymerization, which specifically occurred during the hydrothermal step, mediating and tuning its conversion to melanin-like oligomers. Trasmission electron microscopy (TEM) images proved the efficacy of the proposed synthesis approach in tuning the formation of nanosized globular nanostructures, with high biocide performances. The obtained findings could provide strategic guidelines to set up biomimetic processes, exploiting the catechol-metal complex to obtain hybrid melanin-like nanosystems with optimized multifunctional behavior.

Conium maculatum is a nitrophilous weed belonging to the Apiaceae family and occurring in hedgerows, pastures, waste ground, along rivers and roadsides. Little is known on the chemistry and bioactivity of other secondary metabolites occurring in the plant. In the present work, we have analysed the chemical composition and antimicrobial activity of the essential oils hydrodistilled from leaves and inflorescenes of C. maculatum growing in Sicily, Italy. The composition of essential oils was achieved by gas chromatography-mass spectrometry (GC-MS) analysis, whereas the inhibitory effects on the growth of two Gram negative strains, namely Escherichia coli and Pseudomonas aeruginosa were assessed by two different analysis. The essential oils exhibited different chemical profiles (1-butylpiperidine and myrcene in the inflorescenes), (mostly (E)-caryophyllene in the leaves). The latter oil was particularly active in inhibiting the growth of P. aeruginosa. These results shed light on the possible application of hemlock essential oils as antimicrobial agents.

Bioinspired melanin based hybrid materials hold huge promise for developing multifunctional systems for a considerable set of applications. Yet, control of melanogenic pathway is a big challenge to allow rational design of nanostructured systems with tuned structures and improved properties. This study proves the ability of titanium ions interactions with melanin precursors in directing melanogenic pathway. To this purpose complementary spectroscopic evidences were collected to reveal that in the presence of a TiO2-sol, amino-acid complex of Ti(IV) ions and DOPA actually inhibits its cyclization, during oxidative process, thus leading to DOPA-based polyphenols, stable even in oxidative environment, rather than eumelanin. This hugely impacts on the biological properties of the final hybrid systems which, discloses relevant and durable antioxidant behavior but poor antimicrobial activity differently from DHICA-based hybrid nanostructures. Overall this study, discloses the high potential of ceramic templated approach in combination with the selection of melanin precursor in achieving a fine tuning of physico-chemical as well as bioactivity of melanin-TiO2 nanostructures, opening new scenarios towards the design of cutting-edge biomaterials with tailored biological properties.

Heat stress affects the yield of medicinal plants and can reduce biomass and/or metabolite production. In order to evaluate the effect of heat-induced stress on the essential oil production in Mentha x piperita L. var. Mitcham (Mitcham mint) and Mentha arvensis var. piperascens Malinv. ex L. H. Bailey (Japanese mint), we studied the chemical composition of the oils of the two mint species under different heat shock stresses in growth chambers. The antibacterial activity of the essential oils was also evaluated, microscopic observation (fluorescence and electron transmission) was used to assess the effect of the tested samples on bacterial growth. The results obtained shed light on the mint essential oils composition and biological activity in relation to heat stress.

Heat stress affects the yield of medicinal plants and can reduce biomass and/or metabolite production. In order to evaluate the effect of heat-induced stress on the essential oil production in Mentha x piperita L. var. Mitcham (Mitcham mint) and Mentha x arvensis var. piperascens Malinv. ex L. H. Bailey (Japanese mint), we studied the chemical composition of the oils of the two mint species under different heat shock stress in growth chambers. The antibacterial activity of the essential oils was also evaluated; microscopic observation (fluorescence and electron transmission) was used to assess the effect of the tested samples on bacterial growth. The results obtained shed light on the mint essential oils composition and biological activity in relation to heat stress.

Intrinsic biocide efficacy of eumelanins can be markedly enhanced through a templated formation in the presence of a TiO

Bioactive peptides derived from the receptor-binding region of human apolipoprotein E have previously been reported. All these peptides, encompassing fragments of this region or designed on the basis of short repeated cationic sequences identified in the same region, show toxic activities against a broad spectrum of bacteria and interesting immunomodulatory effects. However, the ability of these molecules to exert antibiofilm properties has not been described so far. In the present work, we report the characterization of a novel peptide, corresponding to residues 133 to 167 of human apolipoprotein E, here named ApoE (133-167). This peptide, besides presenting interesting properties comparable with those reported for other ApoE-derived peptides, such as a direct killing activity against a broad spectrum of bacteria or the ability to downregulate lipopolysaccharide-induced cytokine release, is also endowed with significant antibiofilm properties. Indeed, the peptide is able to strongly affect the formation of the extracellular matrix and also the viability of encapsulated bacteria. Noteworthy, ApoE (133-167) is not toxic toward human and murine cell lines and is able to assume ordered conformations in the presence of membrane mimicking agents. Taken together, collected evidences about biological and structural properties of ApoE (133-167) open new perspectives in the design of therapeutic agents based on human-derived bioactive peptides. Copyright © 2018 European Peptide Society and John Wiley & Sons, Ltd.

Introduzione: Il riconoscimento intra-operatorio delle metastasi nel linfonodo sentinella, in pazienti affetti da cancro della mammella, è utile al fine di procedere ad una linfoadenectomia ascellare immediata nel corso del medesimo intervento. Ciò è fondamentale per evitare una terapia adiuvante tardiva ed un incremento della morbilità e dei costi sanitari. Scopo di tale lavoro è dimostrare che, la metodica citologica “touch-imprint” (TIC), utilizzata presso l’ Azienda Ospedaliero-Universitaria di Trieste, risponde a tale necessità e nel contempo valutarne l’affidabilità. Materiali e metodi: Nel periodo 2009-2012, presso la nostra struttura sono stati operati 690 carcinomi mammari, di cui 479 (69.4%) sono stati selezionati per la ricerca del linfonodo sentinella con radiocolloide. In 347 carcinomi di dimensioni inferiori o uguali a T2 è stata eseguita la metodica citologica TIC; il linfonodo sentinella è stato successivamente sottoposto all’ analisi istologica standard (sezioni seriate ogni 100 micron per ematossilina-eosina e immunoistochimica) che è stato assunta come “gold standard”. Risultati: Su 347 TIC 298 casi erano concordanti con la diagnosi istologica (38 veri positivi e 260 veri negativi). Dei 49 casi risultati falsi negativi, l’analisi definitiva ha dimostrato 28 casi di micrometastasi e 21 casi di macrometastasi, mentre dei 38 casi positivi al TIC, 35 risultavano macrometastasi, 2 micrometastasi e 1 caso di cellule tumorali isolate. La sensibilità e specificità del TIC per macrometastasi sono rispettivamente 64.4% e 100%. Solo 29 casi su 347, pari all’ 8.3%, sono stati sottoposti a radicalizzazione ascellare differita, mentre nel periodo 2005-2008, prima dell’introduzione del TIC,utilizzando l’analisi istologica standard del linfonodo sentinella, tale percentuale era del 18.2%. Discussione e conclusioni: Grazie alla metodica TIC il tasso di dissezioni ascellari in differita è diminuito notevolmente (dal 18.2% all’8.3%). Se gli studi, in corso di validazione definitiva, dimostreranno che la linfoadenectomia ascellare nel trattamento delle micrometastasi non è necessaria, si può ipotizzare che il numero di reinterventi sull’ascella possa ulteriormente ridursi. Nella nostra esperienza, grazie alla discreta sensibilità del TIC per le macrometastasi legata all’ ottima confidenza del patologo con i preparati citologici, è stato possibile migliorare in maniera rilevante l’approccio chirurgico sull’ascella ed il timing oncologico, senza impegno aggiuntivo di risorse economiche.

High- and low-grade cervical lesions were analyzed for the presence of polyomavirus (PYV) and human papillomavirus (HPV) sequences. In precancerous cervical lesions, the overall prevalence of PYV sequences was 44% (41/93). Specifically, among the PYV-positive samples, 83% (34/41) tested positive for BK polyomavirus (BKV) sequences, whereas 17% (7/41) were positive for JC-virus. None of the samples were positive for simian virus 40. The presence of BKV DNA in high-grade squamous intraepithelial lesions was confirmed by in situ PCR. BKV sequences were detected more frequently in high-grade squamous intraepithelial lesions, together with the genotype HPV-16. The association of BKV with precancerous cervical lesions suggests that this polyomavirus participates with HPV-16 in the cell transformation process. Alternatively, BKV might multiply better in HPV-16-positive cells from precancerous cervical lesions than in HPV-16-negative cells.