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Bacteriocins is the name given to products of the secondary metabolism of many bacterial genera that must display antimicrobial activity. Although there are several bacteriocins described today, it has not been possible to reach a consensus on the method of classification for these biomolecules. In addition, many of them are not yet authorized for therapeutic use against multi-drug-resistant microorganisms due to possible toxic effects. However, recent research has achieved considerable progress in the understanding, classification, and elucidation of their mechanisms of action against microorganisms, which are of medical and biotechnological interest. Therefore, in more current times, protocols are already being conducted for their optimal use, in the hopes of solving multiple health and food conservation problems. This review aims to synthetize the information available nowadays regarding bacteriocins, and their classification, while also providing an insight into the future possibilities of their usage for both the pharmaceutical, food, and biotechnological industry.

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Ketorolac, a highly persistent NSAID of environmental concern, was significantly removed from water (80% removal) through photoelectrocatalysis where titanium dioxide nanotubes prepared by Ti foil electrochemical anodization at 30 V were used as photoanodes. Fifteen milligrams per liter of ketorolac solutions in a 0.05 M Na2SO4 aqueous medium was subjected to irradiation from a 365-nm light with an intensity of 1 mWcm-2 and under an applied potential of 1.3 V (vs. Hg/Hg2SO4/sat.K2SO4) at pH 6.0. When each process (photo and electrocatalysis) was carried out separately, less than 20% drug removal was achieved as monitored through UV-vis spectrophotometry. Through scavenging experiments, direct oxidation on the photogenerated holes and oxidation by hydroxyl radical formation were found to play a key role on ketorolac's degradation. Chemical oxygen demand (COD) analyses also showed a significant COD decreased (68%) since the initial COD value was 31.3 mg O2/L and the final COD value was 10.1 mg O2/L. A 48% mineralization was also achieved, as shown by total organic carbon (TOC) analyses. These results showed that electrodes based on titania nanotubes are a promising alternative material for simultaneous photocatalytic and electrocatalytic processes in water remediation.

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BACKGROUND: The inflammatory process in aortic valvular stenosis persists after surgery to replace the valve in almost half of the patients. No association has been found to its persistence. The main objective of this study was to evaluate the inflammatory response in patients with aortic stenosis through the determination of several biomarkers in plasma measured before and after the valvular replacement and to seek an association with the type of prosthesis used. METHODS: This is an observational study with a follow up of 6 months in subjects with severe aortic stenosis. Seric concentrations of TNFa, IL-1, IL-6 and ICAM and echocardiographic variables were quantified previous to the surgery and a week and 6 months after it. A group of control subjects paired by age and gender was included. RESULTS: Seventy-nine subjects were studied of which 57% were male; the average age was of 59 (± 11.4) years. Previous to surgery, the concentration of cytokines was higher in patients than in control subjects. A biological prosthesis was implanted in 48 patients and a mechanical prosthesis in 31. Both, types of prosthesis have components made of titanium. The echocardiograms 1 week and 6 months after the surgery showed a decrease in the mean aortic gradient and an increase in the valvular area (p = 0.001). Half of the patients still showed high proinflammatory cytokine levels. There were no differences according to the type of prosthesis implanted after adjustments for demographic variables, comorbidities and echocardiographic data. CONCLUSIONS: The inflammatory response caused by both types of valvular prothesis at 6 months after implantation were similar. Both types of prosthesis are recommended, they had similarities in hemodynamic profiles registered with Doppler echocardiography. Age of the patient or the suitability use of anticoagulants determines the type of prosthesis to be used.

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Sequential helminth egg inactivation using a solar driven advanced oxidation process (AOP) followed by chlorine was achieved. The photo-assisted Fenton process was tested alone under different H(2)O(2) and/or Fe(II) concentrations to assess its ability to inactivate Ascaris suum eggs. The effect of free chlorine alone was also tested. The lowest egg inactivation results were found using Fe(II) or H(2)O(2) separately (5 and 140 mmol L(-1), respectively) in dark conditions, which showed about 28% inactivation of helminth eggs. By combining Fe(II) and H(2)O(2) at the same concentrations described earlier, 55% of helminth egg inactivation was achieved. By increasing the reagent's concentration two-fold, 83% egg inactivation was achieved after 120 min of reaction time. Process efficiency was enhanced by solar excitation. Using solar disinfection only, the A. suum eggs inactivation reached was the lowest observed (58% egg inactivation after 120 min (120 kJ L(-1))), compared with tests using the photo-Fenton process. The use of the photo-Fenton reaction enhanced the process up to over 99% of egg inactivation after 120 kJ L(-1) when the highest Fe(II) and H(2)O(2) concentration was tested. Practically no effect on the helminth eggs was observed with free chlorine alone after 550 mg min L(-1) was used. Egg inactivation in the range of 25-30% was obtained for sequential processes (AOP then chlorine) using about 150 mg min L(-1).

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