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Fatima García-Villén,1 Angela Faccendini,2 Carola Aguzzi,1 Pilar Cerezo,1 Maria Cristina Bonferoni,2 Silvia Rossi,2 Pietro Grisoli,2 Marco Ruggeri,2 Franca Ferrari,2 Giuseppina Sandri,2 Cesar Viseras11Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Granada, Campus of Cartuja, Granada, Spain; 2Department of Drug Sciences, Faculty of Pharmacy, University of Pavia, Pavia 27100, ItalyBackground: Chronic cutaneous wounds represent amajor issue in medical care and are often prone to infections.Purpose: The aim of this study was the design of a clay mineral-drug nanocomposite based on montmorillonite and norfloxacin (NF, antimicrobial drug) as a powder for cutaneous application, to enhance wound healing in infected skin lesions.Methods: The nanocomposite has been prepared by means of an intercalation solution procedure. Adsorption isotherm, solid-state characterization of the nanocomposite, drug loading capacity and its release have been performed. Moreover, cytocompatibility, in vitro fibroblast proliferation and antimicrobial activity against Pseudomonas aeruginosa and Staphylococcus aureus were assessed.Results: The clay drug adsorption isotherm demonstrates that the mechanism of NF intercalation into montmorillonite galleries is the adsorption as one single process, due to the charge–charge interaction between protonated NF and negatively charged montmorillonite edges in the interlayer space. Nanocomposite is biocompatible and it is characterized by antimicrobial activity greater than the free drug: this is due to its nanostructure and controlled drug release properties.Conclusion: Considering the results obtained, NF–montmorillonite nanocomposite seems a promising tool to treat infected skin lesions or skin wounds prone to infection, as chronic ulcers (diabetic foot, venous leg ulcers) and burns.Keywords: montmorillonite, norfloxacin, nanocomposite, solid state characterization, wound healing

Studi condotti negli ultimi due decenni hanno messo in evidenza numerose attività biologiche possedute dal vino oltre a quelle dovute al suo contenuto in etanolo. E’ ormai accertato che un moderato consumo di vino determina una diminuzione del rischio di sviluppare gravi e diffuse patologie croniche quali neoplasie e malattie cardio-vascolari. E’ stato dimostrato che gli effetti positivi della bevanda sono dovuti alle proprietà antiossidanti e antiradicaliche dei componenti polifenolici dei quali è particolarmente ricco il vino rosso. Esso possiede anche attività antibatterica nei confronti di diversi microrganismi tra cui l’Helicobacter pilori. Questa attività biologica è dovuta al resveratrolo, derivato stilbenico che nei vegetali ha funzione di fitoalexina. Il resveratrolo è risultato attivo anche contro alcuni batteri e dermatofiti, responsabili delle più comuni infezioni della pelle umana. Il vino è inoltre risultato attivo in vitro nei confronti di numerosi batteri enteropatogeni. In questo caso è risultato responsabile dell’attività l’acido acetico contenuto nella bevanda. In considerazione del fatto che la bevanda viene ripetutamente consumata durante un pasto e che per questo la sua azione potrebbe essere particolarmente importante per la salute del cavo orale, abbiamo esteso lo studio dell’attività antibatterica e battericida del vino verificando gli effetti nel vino bianco nei confronti degli Streptococchi orali che svolgono un ruolo importante nello sviluppo della carie e delle patologie parodontali. Un campione di vino bianco del commercio è stato saggiato nei confronti di nove Streptococchi colonizzatori del cavo orale. Esso è risultato attivo contro numerosi Streptococchi compreso lo S. mutans, il principale agente eziologico della carie. L’isolamento dal campione di vino analizzato dei componenti attivi è stato condotto mediante dialisi seguita da estrazione in fase solida. E’ risultata attiva la frazione costituita dai componenti più polari indicando che l’attività rilevata per la bevanda, potrebbe essere dovuta agli acidi organici prodotti durante il processo di fermentazione. L’attività di tali acidi contro lo S. mutans è stata verificata utilizzando standards del commercio. Il più attivo è risultato l’acido succinico seguito dall’acido malico, lattico, tartarico, citrico e acetico.

In precedenti ricerche i componenti idrosolubili della Brassica oleracea var, botrytis L. avevano mostrato attività antiradicalica nel sistema chimico contenente acido linoleico-beta carotene e nel sistema biologico costituito dalla frazione microsomiale di epatociti di ratto. Scopo di questo lavoro è valutare la capacità degli stessi componenti di agire in un altro sistema biologico quale quello costituito da colture di Staphylococcus aureus. L'attività antiossidante del vegetale è determinata come attività protettiva nei confronti dell'azione citotossica di una miscela ossidante contenente un iniziatore radicalico, alla quale viene esposta la colture del microrganismo.

Wine contains a number of biologically active compounds with beneficial effects on human health. The antibacterial action of commercial red and white wines against oral streptococci responsible for caries development and against S. pyogenes responsible for pharyngitis was studied. Its postcontact effect against S. mutans was also studied. Both wines displayed activity. The compounds responsible for such activities were succinic, malic, lactic, tartaric, citric, and acetic acid. The synthetic mixtures of the organic acids tested at the concentrations found in wine had greater antibacterial activity than the beverages, indicating that in wine they are inhibited by other components. Wine polyphenols displayed no activity against oral streptococci or S. pyogenes. Findings show that wine is active against oral streptococci and S. pyogenes and suggest that it enhances oral health.

Green and roasted coffees of the two most used species, Coffea arabica and Coffea robusta, several commercial coffee samples, and known coffee components were analyzed for their ability to interfere with Streptococcus mutans' sucrose-independent adsorption to saliva-coated hydroxyapatite (HA) beads. All coffee solutions showed high antiadhesive properties. The inhibition of S. mutans' adsorption to HA beads was observed both when coffee was present in the adsorption mixture and when it was used to pretreat the beads, suggesting that coffee active molecules may adsorb to a host surface, preventing the tooth receptor from interacting with any bacterial adhesions. Among the known tested coffee components, trigonelline and nicotinic and chlorogenic acids have been shown to be very active. Dialysis separation of roasted coffee components also showed that a coffee component fraction with 1000 Da < MW < 3500 Da, commonly considered as low MW coffee melanoidins, may sensibly contribute to the roasted coffee's antiadhesive properties. The obtained results showed that all coffee solutions have antiadhesive properties, which are due to both naturally occurring and roasting-induced molecules.

This paper reports the content in macronutrients, free sugars, polyphenols, and inorganic ions, known to exert any positive or negative action on microbial oral disease such as caries and gingivitis, of seven food/beverages (red chicory, mushroom, raspberry, green and black tea, cranberry juice, dark beer). Tea leaves resulted the richest material in all the detected ions, anyway tea beverages resulted the richest just in fluoride. The highest content in zinc was in chicory, raspberry and mushroom. Raspberry is the richest food in strontium and boron, beer in selenium, raspberry and mushroom in copper. Beer, cranberry juice and, especially green and black tea are very rich in polyphenols, confirming these beverages as important sources of such healthy substances. The fractionation, carried out on the basis of the molecular mass (MM), of the water soluble components occurring in raspberry, chicory, and mushroom extracts (which in microbiological assays revealed the highest potential action against oral pathogens), showed that both the high and low MM fractions are active, with the low MM fractions displaying the highest potential action for all the fractionated extracts. Our findings show that more compounds that can play a different active role occur in these foods.

Some beverages and foods protect tooth surfaces against Streptococcus mutans colonization. Adhesion of S. mutans is a crucial step in the initiation and development of dental caries. In this study, we showed that barley coffee (BC), a beverage made from roasted barley, interferes with S. mutans adsorption to hydroxyapatite (HA), and we identified its antiadhesive components. The effects of sublethal concentrations (sub-MICs) of BC on the adhesion of S. mutans to saliva-coated HA beads were assessed using three experimental approaches: (A) Beads were pretreated with BC before adding bacteria, (B) BC and bacteria were added to the beads simultaneously, and (C) streptococci grown in the presence of sub-MICs of BC were added to the beads. All treatments induced variable but significant inhibition of S. mutans sucrose-dependent and -independent adherence to HA. Similar results were obtained with other oral streptococci. BC components were fractioned by dialysis and gel filtration chromatography; the 1000 kDa MM fraction, which consists of a potent brown antioxidant, melanoidin, both displayed antiadhesive properties. High-MM melanoidin was not detected in unroasted barley, indicating that it forms during the roasting process. Results suggest that BC consumption may influence the colonization of tooth surfaces by cariogenic bacteria.