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Decontamination of surfaces and medical equipment is integral to the control of Clostridium difficile transmission, and many products claim to inactivate this bacterium effectively. Thirty-two disinfectants were tested against spores of C. difficile in a suspension test based on European Standard BS EN 13704:2002, with contact times of 1 and 60 min in simulations of clean (0.3% albumin) and dirty (3% albumin) conditions. The addition of a 1-min contact time was chosen as a more realistic simulation of probable real-life exposures in the situation being modelled than the 60 min specified by the Standard. The manufacturer's lowest recommended concentrations for use were tested. Sixteen products achieved >10(3) reduction in viability after 60 min (the pass criterion for the Standard) under both clean and dirty conditions. However, only eight products achieved >10(3) reduction in viability within 1 min under dirty conditions. Three products failed to reduce the viability of the C. difficile spores by a factor of 10(3) in any of the test conditions. This study highlights that the application of disinfectants claiming to be sporicidal is not, in itself, a panacea in the environmental control of C. difficile, but that carefully chosen environmental disinfectants could form part of a wider raft of control measures that include a range of selected cleaning strategies.

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Piper cubeba L. (Piperaceae), conocida comúnmente como ‘cubeb’, es autóctona de Indonesia y también se encuentraen muchos otros países del sureste de Asia, así como en algunos países africanos.Esta planta se ha utilizado como un popular aditivo alimentario y, en la medicina tradicional, para tratar diversasdolencias, especialmente infecciones bacterianas. Para evaluar la actividad antioxidante (barrido de radicales libres)y la actividad antibacteriana de los extractos de n-hexano, diclorometano (DCM) y metanol (MeOH) de las bayassecas (fruto) de esta planta, se llevó a cabo un ensayo 2,2-difenil-1-picrilhidracil (DPPH) y un ensayo antimicrobianobasado en microtitulación que incorporaba resazurina como indicador del crecimiento celular, respectivamente. Aunquetodos los extractos mostraron actividad antioxidante en el ensayo cualitativo, la actividad antioxidante más destacadase observó con el extracto de MeOH en el ensayo cuantitativo con un valor de RC50 de 2,71 x 10-1 mg/mL.La potencia antioxidante del extracto de DCM fue aproximadamente 3 veces menor (RC50 = 6,50 x 10-1 mg/mL)que la del extracto de MeOH.Ninguno de los extractos mostró propiedades antibacterianas frente a Bacillus subtilis, Escherichia coli y Escherichiacoli resistente a la ampicilina. Aunque ambos extractos, el n-hexano y el DCM, inhibieron el crecimiento de Bacilluscereus, Pseudomonas aeruginosa y Staphylococcus aureus, el extracto de MeOH sólo mostró actividad frente a B.cereus y P. aeruginosa. El extracto de n-hexano fue el que mostró mayor potencia antibacteriana frente a B. cereus,con un valor de concentración inhibitoria mínima (CIM) de 1,56 mg/mL. Se observó que todas las actividades antibacterianasde los extractos resultaron más bacteriostáticas que bactericidas

Piper cubeba L. (Piperaceae), commonly known as ‘cubeb’, is native to Indonesia, and also found in many other countriesof the South-East Asia, and in some African countries. This plant has been used as a popular food additive, andin folklore medicine to treat various ailments, particularly bacterial infections. The n-hexane, dichloromethane (DCM)and methanol (MeOH) extracts of the dried berries (fruit) of this plant were assessed for their antioxidant (free radicalscavenging) and antibacterial activities using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and the micro titre basedantimicrobial assay incorporating resazurin as an indicator of cell growth, respectively. While all extracts showed antioxidantactivity in the qualitative assay, the most prominent antioxidant activity was observed with the MeOH extract inthe quantitative assay with a RC50 value of 2.71 x 10-1 mg/mL. The antioxidant potency of the DCM extract was about3 fold less (RC50 = 6.50 x 10-1 mg/mL) than that of the MeOH extract. None of the extracts showed any antibacterialproperty against Bacillus subtilis, Escherichia coli, and ampicillin resistant Escherichia coli. While both the n-hexaneand the DCM extracts inhibited the growth of Bacillus cereus, Pseudomonas aeruginosa and Staphylococcus aureus, theMeOH extract was active only against B. cereus and P. aeruginosa. The most potent antibacterial activity was displayedby the n-hexane extract against B. cereus with an MIC value of 1.56 mg/mL. All antibacterial activities of the extractswere found to be bacteriostatic rather than bactericidal (AU)

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