Pharmaceutical Waste 2,4-dichlorophenol is Biodegradable by Pseudomonas Bacteria.

Pseudomonas alcaligenes was found to be an effective biodegrader of 2,4-dichloropjenol(DCP), a waste product of pharmaceutical industries, at pH 7 and 35 °C after ultraviolet light exposure . The chlorinated aromatic compound 2,4-dichlorophenol is an environmental pollutant that can be synthesized into larger phenols, pesticides, and herbicides. Pseudomonas alcaligenes extracted from sewage sludge were tested for growth and biodegradation based on various 2,4-DCP concentrations, UV radiation exposure, temperature at pH 7, and pH in 25 °C. The amount of 2,4 DCP that degraded from Pseudomonas alcaligenes  correlated significantly with increasing values of these four factors, in particular the amount of 2,4-DCP that degraded increased significantly after 144 hours of UV radiation exposure  (Elkarmi et al. 2009). The degradation of 2,4 DCP by Pseudomonas alcaligenes  would be highly effective in bioremediation programs for reducing the amount of pharmaceuticals in the environment, especially in sewage  treatment plants where most pharmaceuticals are not eliminated during the cleaning process. — Kevon White 
Elkarmi, Ali., Abu-Elteen K., Atta A., Abu-Sbitan N., 2009. Biodegradation of 2,4-dichlorophenol originating from pharmaceutical industries. African Journal of Biotechnology  8, 2558–2564.   

 Ali Z. Elkarmi and colleagues from Hashemite University extracted and identified Pseudomonas alcaligenes from the wastewater of two pharmaceutical and healthcare industries.  The sewage was centrifuged for 30 minutes to obtain 200 mg of sludge, which was then added to sterilized flasks containing 20 ml of chlorophenol enrichment media and 100 mg/l 2,4-dichlorophenol. The mixture along with a second mixture from 50 ml of nutrient broth and 0.5 ml of the first suspension incubated were incubated 30 °C for four days. Nutrient agar plates containing 100 ml/I 2,4-DCP were inoculated with 0.3 ml of the  second mixture and both were incubated at 37 °C for four days. The results were sent to the Jordan University hospital, which confirmed the identity of the bacterial species Pseudomonas alcaligenes. The colonies of Pseudomonas alcaligenes were placed in nutrient agar plates of 1 g/l cetrimide where they were tested for 2,4-DCP concentrations in increments of 20 mg/l starting from 120 mg/l to 300 mg/l.  Isolated colonies of Pseudomonas alcaligenes were then subjected to UV radiation for 24, 48, 72, and 96 hours in 2,4-DCP concentrations at increments of 20 mg/l starting from 240 mg/l to 400 mg/l.  The UV irradiated samples were then cultivated in a bioreactor were biodegradability of  340 mg/l  2,4-DCP was tested from temperatures of 25, 30, 35, and 40 °C and pH values ranging of 6.5, 7.0 and 8.0.  The final results were compared for statistical significance using one-way ANOVA test. 
Without UV radiation the amount of bacteria that grew in the 2,4-DCP culture decreased with increasing concentration. From 180 mg/l to 220 mg/l 2,4-DCP, the bacteria exhibited weak growth decreasing from  9.60  to 6.07 log10 of CFU/ml respectively. The amount of 2.4-DCP after UV radiation was added, however, increased the limit for tolerance and biodegradation of 2,4-DCP significantly; at a concentration of 200 mg/l of 2,4-DCP, the growth of bacteria increased from 8.40 mg/l to 9.08 mg/l log10 of CFU/ml. After UV radiation exposure the limit for the concentration of 2,4-DCP to decrease growth was raised to  380 mg/l at 6.80  log10 of CFU/ml. At a pH of 7.0, growths were best at a temperature of 35 °C after 168 hours. At a temperature of 25 °C, growths were best at a pH of 7.0 after 168. The ANOVA test indicated that there were significant correlations between pH, UV radiation, concentration of 2,4-DCP  and temperature. A possible use for the Pseudomonas alcaligenes would be in bioremediation and sewage treatment where pharmaceuticals are often not eliminated from the wastewater treatment process. 

Are Rising Temperatures Responsible for the Rates of Tularemia in Sweden?

The number of reported human tularemia cases will steadily increase from 2010 to 2100 in the five high-endemic counties of Dalarna, Gävleborg, Norrbotten, Värmland, and Örebro.  The predicted increase in the incidences of human tularemia has been linked to the steadily warmer climate of Sweden enabling certain parasites to proliferate.  The parasites that spread the bacterium Francisella tularensis include ticks, mosquitoes, fleas, horse flies, and deerflies. Though the level of precipitation was predicted to remain stable and constant throughout the 2010–2100 periods, indicating that the increase in parasites is not due to increased rainfall, the rate of tularemia still increased as the climate became warmer (Rydén et al. 2009). The high localization of tularemia, the population patterns of its vectors and its incidences on the local population will need to be further researched in order to understand the reasons why increased tularemia epidemics correlate with increased temperature. Kevon White
Rydén, P., Sjöstedt, A., Johansson, A., 2009. Effects of climate change on tularaemia disease activity in Sweden. Citation: Global Health Action.  DOI: 10.3402/gha.v2i0.2063.

Patrick Rydén and colleagues from Umeå University analyzed data about human tularemia outbreaks in Sweden from 1997–2008. A 140-year model for simulation data was constructed and performed. Scenario data was taken using a climate model RCA3 and the IPCC Special Report on Emissions data. The data were arranged into 50 x 50 km square regions. Empirical data of disease onset from 379 individuals during 1981–2007 were collected from Dalarna County and used to determine the temperature and time parameters of human tularemia epidemics. The monthly average values were calculated for temperature and precipitation using the 50 x 50 km square regions.  The duration of a tularemia epidemic was determined using the mean temperatures from May to October and time plots from the first and last human tularemia case for each year, region, and local outbreak area.

Investigations on the five high tularemia-endemic areas showed that the incidences of human tularemia from 1997–2008 ranged from 40.1 to 81.1% of the total tularemia incidences in Sweden. All five counties contain 14.61% of the Swedish population at 1,352,558 human inhabitants. The number of incidences during the 1997–2008 range from 0 in the Värmland and Örebro counties in 1997 to 216 in Dalarna County in 2003. However, the distribution in the five counties was uneven, mainly due to the high localization of the disease. The tularemia prediction model indicated that the summer conditions will last longer due to an increase in temperatures by 2° C during 2010–2100. The precipitation was stable throughout the period and did not increase significantly. The duration of the temperate sensitive outbreaks will vary from 3.5 weeks in Norrbotten to 6.6 weeks in Värmland during 2010–2100. An exact relationship between the temperature and the rate of transmission has not been clearly documented; however, because precipitation is stable throughout the 2010–2100 periods then the amount of rainfall is insignificant to the rate of transmission. More analyses will have to be taken in order to determine the exact causes of the disease’s restrictive locality, the vector populations that house the bacterium Francisella tularensis, and the responses of the flora, fauna, and transmission rates to increased 

Is Honey an Effective Medicine for Antibiotic Resistant Diseases?

Leptospermum honey is effective against various types of antibiotic resistant bacteria including Staphylococcus aureus, (MRSA), Acinetobacter calcoaceticus, and Escherichia coli. Additionally the bacteria show no resistance to Leptospermum honey even after repeated exposure (Blair et al. 2009). Leptospermum honey was found to be effective at low concentrations from 4% to 14.8%. It acts differently from other antimicrobial agents by providing moisture, sugars, and hydrogen peroxide as well as an unprecedented number of compounds that have yet to be fully researched. As there are few scientific studies that support the use of honey in wound treatment, more will be needed to understand all of the effects of using honey to treat or prevent infections caused by antibiotic resistant diseases. Kevon White
Blair, E., Cokcetin, N., Harry E., Carter D., 2009. The unusual antibacterial activity of medical-grade Leptospermum  honey: antibacterial spectrum, resistance and transcriptome  analysis. Eur J Clin Microbiol Infect Dis  28, 1199–1208
S.E. Blair and Colleagues from the University of Sydney and the University of Technology in Sydney conducted several tests using four different types of honey: Medihoney®, Leptospermum honey, Lucerne Blueweed honey, and a controlled artificial honey made from several sugars. The Medihoney® was added slowly to various agar plates containing 13 different types of infectious bacteria. The MIC was then recorded from the results.  A marcodilution method test was done later in which all four honeys were diluted with water and was slowly added to the bacteria to determine the MBC of the bacterium. The results of the different honeys were compared with those of Oxcallin, Tetracycline, and Ciprofloxacin.  The different honeys along with the three antibiotic medicines were tested repeatedly over the bacterial strains to determine resistance capabilities. Lastly, a macroarray analysis was performed on 6% honey solutions of Medihoney® and the inactive Leptospermum honey. A culture of E. coli was then combined with the honeys to determine the gene expression of the two samples.
The Medihoney® inhibited the growth of bacteria significantly compared to the artificial control honey.  The MIC for the Medihoney® ranged from 4%–16% while the artificial honey’s MIC ranged from 20% to beyond 25%. Of the bacteria in the first experiment, MRSA had the least resistance to honey, but it resisted the artificial honey by nearly five times that value. Though the honey is less effective at first, the bacteria do not seem to develop any resistance to it, even after being subjected to repeated trials of honey.  When compared to Oxacillin, Tetracyclinen and Ciprofloxacin the percentage of honey needed to inhibit bacterial growth initially was much higher; however, unlike the previous three medicines, the honey does not allow the bacteria to develop a resistance to it. The expression of several E.coli genes when mixed with honey indicates that it may cause a significant change in the protein and binding structures of the bacteria. One-hundred-twenty-four genes were found to be upregulated or downregulated by the presence of honey.  Of these genes, most were associated with stress responses in the bacteria. This indicates that honey may have an effect on the bacterial gene sequence and may interfere with protein synthesis. Another suggestion by Blair et al. is that the complex nature of the honey and a yet discovered compound could account for its effectiveness in eliminating antibiotic resistant bacteria.   Leptospermum honey has demonstrated the ability to treat an unusually broad number of antibiotic resistant bacteria, and most importantly it is resilient against these strains. Thus its use in western medicine will be important in combating increasingly deadly strains of evolving bacteria.