Background:  High levels of viable Staphylococcus aureus, which are often found on inflamed skin surfaces, are usually associated with atopic dermatitis. Textiles, owing to their high specific surface area and intrinsic hydrophilicity, retain moisture while also providing excellent environmental conditions for microbial growth and proliferation. Recently, a number of chemicals have been added to textiles, so as to confer antimicrobial activity. Aims:  To evaluate the antimicrobial action of chitosan upon selected skin staphylococci. Methods and Results:  We isolated staphylococci from normal skin of 24 volunteers and studied their survival upon contact with chitosan‐impregnated cotton fabric. Low and high molecular weight chitosans were used at two concentrations; all four did effectively reduce the growth of some staphylococci (namely Staph. aureus), by up to 5 log cycles, thus unfolding a potential towards control and even prevention of related skin disorders. Conclusion:  Our data suggest an effective, but selective antibacterial action of chitosans towards skin bacteria. Significance and Impact of the Study:  The possibility to use a natural biopolymer incorporated in a textile to alleviate and even treat some of the symptoms associated with this skin condition may raise an alternative to existing medical treatments. The selectivity observed prevents full elimination of bacteria from the skin surface, which is an advantage.

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The potential of the microbial communities present in the intertidal zone of an unimpacted beach (a beach that did not suffer any significant oil spill) to degrade hydrocarbons was investigated. For that, laboratory-based microcosms (50-ml flasks) were set up with sandy beach sediment spiked with crude oil and incubated with local seawater for 15 days in the dark. Three bioremediation treatments were tested (biostimulation (BS), autochthonous bioaugmentation (AB), and combined treatment of biostimulation + bioaugmentation (BS + AB)) and the results were compared with natural attenuation (NA). Visual inspection showed clearly an oil solubility increase (confirmed by a higher hydrocarbons concentration in supernatant solutions) for all tested treatments when compared to NA. Significant degradation of the oil, shown by different profiles of petroleum hydrocarbons, was also observed for the different treatments particularly for BS + AB. Therefore, the microbial community of this unimpacted beach sediment could respond to an oil spill, degrading hydrocarbons. But to increase the natural attenuation pace, obtained results indicated that BS + AB is an appropriate approach for the bioremediation of beaches recently impacted by an oil spill. The autochthonous microbial cultures can be obtained "before" or "after" the contamination of the target site, being inoculated into the site right after it contamination.

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