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This study explores the potential of geranium essential oil as a natural solution for combating marine biofouling, addressing the environmental concerns associated with commercial antifouling coatings. Compounds with bactericidal activities were identified by 13Carbon nuclear magnetic resonance (13C NMR). Thermogravimetric analysis (TGA) revealed minimal impact on film thermal stability, maintaining suitability for antifouling applications. The addition of essential oil induced changes in the morphology of the film and Fourier transform infrared spectroscopy (FTIR) analysis indicated that oil remained within the film. Optical microscopy showed an increase in coating porosity after immersion in a marine environment. A total of 18 bacterial colonies were isolated, with Psychrobacter adeliensis and Shewanella algidipiscicola being the predominant biofilm-forming species. The geranium essential oil-based coating demonstrated the ability to reduce the formation of Psychrobacter adeliensis biofilms and effectively inhibit macrofouling adhesion for a duration of 11 months.

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Biological methane biodegradation is a promising treatment alternative when the methane produced in waste management facilities cannot be used for energy generation. Two-phase partitioning bioreactors (TPPBs), provided with a non-aqueous phase (NAP) with high affinity for the target pollutant, are particularly suitable for the treatment of poorly water-soluble compounds such as methane. Nevertheless, little is known about the influence of the presence of the NAP on the resulting biodegradation kinetics in TPPBs. In this study, an experimental framework based on the in situ pulse respirometry technique was developed to assess the impact of NAP addition on the methane biodegradation kinetics using Methylosinus sporium as a model methane-degrading microorganism. A comprehensive mass transfer characterization was performed in order to avoid mass transfer limiting scenarios and ensure a correct kinetic parameter characterization. The presence of the NAP mediated significant changes in the apparent kinetic parameters of M. sporium during methane biodegradation, with variations of 60, 120, and 150% in the maximum oxygen uptake rate, half-saturation constant and maximum specific growth rate, respectively, compared with the intrinsic kinetic parameters retrieved from a control without NAP. These significant changes in the kinetic parameters mediated by the NAP must be considered for the design, operation and modeling of TPPBs devoted to air pollution control.

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PURPOSE: To analyze the antimicrobial properties of silicon oil (Óleo de Silicone®, Ophthalmos, Brazil) on in vitro bacterial growth of different microorganisms related to endophthalmitis. METHODS: The following microorganisms were analyzed: (1) Pseudomonas aeruginosa (ATCC 27583); (2) Escherichia coli (ATCC 25922); (3) Staphylococcus aureus (ATCC 25923); (4) Staphylococcus epidermidis (ATCC 12228); (5) Candida albicans (ATCC 10231); (6) Klebsiella pneumoniae (ATCC 13883); and (7) Streptococcus pneumoniae (ATCC 49619). The plates were incubated at 35 ± 2ºC and its growth examined after 24 hours. An empty disk was placed in the center of each plate as a control. RESULTS: No inhibition halos were verified in any of the plates containing the four different concentrations of the bacterial inocula. CONCLUSIONS: The silicon oil 1000 cps does not have any effect on bacterial growth of any of the studied microorganisms.

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PURPOSE: To analyze the antimicrobial properties of silicon oil (Óleo de Silicone®, Ophthalmos, Brazil) on in vitro bacterial growth of different microorganisms related to endophthalmitis. METHODS: The following microorganisms were analyzed: (1) Pseudomonas aeruginosa (ATCC 27583); (2) Escherichia coli (ATCC 25922); (3) Staphylococcus aureus (ATCC 25923); (4) Staphylococcus epidermidis (ATCC 12228); (5) Candida albicans (ATCC 10231); (6) Klebsiella pneumoniae (ATCC 13883); and (7) Streptococcus pneumoniae (ATCC 49619). The plates were incubated at 35 ± 2ºC and its growth examined after 24 hours. An empty disk was placed in the center of each plate as a control. RESULTS: No inhibition halos were verified in any of the plates containing the four different concentrations of the bacterial inocula. CONCLUSIONS: The silicon oil 1000 cps does not have any effect on bacterial growth of any of the studied microrganisms.

OBJETIVO: Analisar as propriedades antimicrobianas do óleo de silicone (Óleo de Silicone®, Ophthalmos, Brazil) no crescimento in vitro de diferentes microrganismos relacionados à endoftalmite. MÉTODOS: Os seguintes microrganismos foram analisados: (1) Pseudomonas aeruginosa (ATCC 27583); (2) Escherichia coli (ATCC 25922); (3) Staphylococcus aureus (ATCC 25923); (4) Staphylococcus epidermidis (ATCC 12228); (5) Candida albicans (ATCC 10231); (6) Klebsiella pneumoniae (ATCC 13883); and (7) Streptococcus pneumoniae (ATCC 49619). As placas foram incubadas à temperatura de 35 ± 2ºC e o seu crescimento examinado após 24 horas. Um disco de papel filtro neutro, sem óleo de silicone, foi posicionado no centro de cada placa como controle. RESULTADOS: Não foram encontrados halos de inibição em nenhuma das placas contendo as diferentes concentrações de inóculo bacteriano estudadas. CONCLUSÕES: O Óleo de Silicone® 1000 cps não apresenta efeito no crescimento bacteriano de nenhum dos microrganismos estudados.

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O objetivo dos autores foi o de avaliar o endotélio corneano nos pacientes submetidos à vitrectomia pars plana com implante de óleo de silicone. Foram selecionados 11 olhos submetidos à cirurgia. Realizou-se microscopia especular no pré-operatório e no 3o. e 6o. mês pós-operatório. A perda de células endoteliais no pós-operatório é mostrada nos olhos fácicos e afácicos.

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