Culturable faecal coliform, epidemic, clinical, faecal and recreational beach enterococci strains possessing putative virulence genes were enumerated over the course of 5 weeks to comparatively assess their persistenc...Culturable faecal coliform, epidemic, clinical, faecal and recreational beach enterococci strains possessing putative virulence genes were enumerated over the course of 5 weeks to comparatively assess their persistence in tropical marine and fresh waters. For the clinical and epidemic strains tested, it took 2.38 ± 0.45 days for a 1-log reduction (T90) in marine water. A higher T90 average of 2.51 ± 0.08 was observed for the commensal and environmental strains. Generally, lower T90 values of 2.14 ± 0.26 and 2.15 ± 0.16 days respectively were observed for hospital and community acquired enterococci strains in fresh water mesocosms subjected to tropical ambient temperature. Beach water enterococci and enterococci recovered from faeces of humans survived for up to 20 days and 23 days respectively in fresh and marine waters. The epidemic strain, MMH594, an esp-positive clinical bacteremia isolate that previously caused multiple infections in a hospital ward outbreak fares favourably well in tropical marine and fresh aquatic environments. For enterococci, the decay rate was approximately 13% higher in fresh water than was observed for marine water. On the contrary, for E. coli, the decay rate was approximately 17% lower in fresh water than was observed in marine water. Generally, the whole, the population trends of E. coli and enterococci in fresh and marine water mesocosms did not reveal any evidence of growth. Our findings suggest that potentially pathogenic bacteria can resume active growth after three weeks of being harboured by the reservoir-beach sand and still pose threat to public health.展开更多
Carbon dioxides (CO<sub>2</sub>) concentration has become much higher every year and this has already become the global issue. Lichen is a symbiotic organism that is best known as the air pollution indicat...Carbon dioxides (CO<sub>2</sub>) concentration has become much higher every year and this has already become the global issue. Lichen is a symbiotic organism that is best known as the air pollution indicator. Based on its frequency and diversity distribution, the level of pollution that has been made can be determined. This re-search was conducted in UKM Fernarium Free Air Carbon Dioxides Enrichment Station (FACE Station) with lichen frequencies and diversities observed and analyzed statistically and graphically. Seven species of li-chens were found at the sampling locations. Findings showed that there was significant relationship in lichen frequency and diversity distribution under elevated CO<sub>2</sub> inside FACE Station with its surrounding.展开更多
文摘Culturable faecal coliform, epidemic, clinical, faecal and recreational beach enterococci strains possessing putative virulence genes were enumerated over the course of 5 weeks to comparatively assess their persistence in tropical marine and fresh waters. For the clinical and epidemic strains tested, it took 2.38 ± 0.45 days for a 1-log reduction (T90) in marine water. A higher T90 average of 2.51 ± 0.08 was observed for the commensal and environmental strains. Generally, lower T90 values of 2.14 ± 0.26 and 2.15 ± 0.16 days respectively were observed for hospital and community acquired enterococci strains in fresh water mesocosms subjected to tropical ambient temperature. Beach water enterococci and enterococci recovered from faeces of humans survived for up to 20 days and 23 days respectively in fresh and marine waters. The epidemic strain, MMH594, an esp-positive clinical bacteremia isolate that previously caused multiple infections in a hospital ward outbreak fares favourably well in tropical marine and fresh aquatic environments. For enterococci, the decay rate was approximately 13% higher in fresh water than was observed for marine water. On the contrary, for E. coli, the decay rate was approximately 17% lower in fresh water than was observed in marine water. Generally, the whole, the population trends of E. coli and enterococci in fresh and marine water mesocosms did not reveal any evidence of growth. Our findings suggest that potentially pathogenic bacteria can resume active growth after three weeks of being harboured by the reservoir-beach sand and still pose threat to public health.
文摘Carbon dioxides (CO<sub>2</sub>) concentration has become much higher every year and this has already become the global issue. Lichen is a symbiotic organism that is best known as the air pollution indicator. Based on its frequency and diversity distribution, the level of pollution that has been made can be determined. This re-search was conducted in UKM Fernarium Free Air Carbon Dioxides Enrichment Station (FACE Station) with lichen frequencies and diversities observed and analyzed statistically and graphically. Seven species of li-chens were found at the sampling locations. Findings showed that there was significant relationship in lichen frequency and diversity distribution under elevated CO<sub>2</sub> inside FACE Station with its surrounding.
