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Indoor air in homes contains a variety of organic agents such as bacteria, endotoxin and fungi. Epidemiological studies have shown links between these components and respiratory problems and the development of allergies. Twenty-eight dwellings located in the Greater Copenhagen area in Denmark were investigated in this study. Temperature, relative humidity and air exchange rate were measured. Dwelling characteristics including floor area, volume of the living room, floor material, year of construction of buildings and floor level were collected. The microbial exposure was measured by quantifying fungi, bacteria and endotoxin concentration in airborne dust collected by Electrostatic Dust fall Collectors (EDCs). The Total Inflammatory Potential (TIP) of the dust was also measured. Significantly higher concentrations of fungi were found in dwellings with high relative humidity (p = 0.03), larger room volume (p = 0.03) and in dwellings located on the second floor or higher (p = 0.02). Small floor area per person and low air exchange rate were significantly associated with increased concentrations of bacteria (both p < 0.01). Spring season (p = 0.01), buildings constructed before the 20th century (p = 0.09) and wooden floor (p = 0.03) were associated with high TIP. In conclusion, people living in smaller dwellings or in dwellings on upper floors are at higher risk of microbial exposure. While TIP was affected by some dwelling characteristics, it was mainly influenced by season. [ABSTRACT FROM AUTHOR]

Abstract: Recently, concerns for the indoor environment have significantly increased due to demands for a better quality of life. The bathroom has the poorest air quality in a building; nevertheless, it usually requires the best cleanliness. Most contamination sources in a bathroom are the unpleasant odor and bacteria due to feces. Instead of an air ventilation system that circulates all of the bathroom air, authors investigate numerically and experimentally a system that entrains the source from a toilet bowl and blocks the source's outflow. The system is simply installed inside the toilet seat. The effects of the suction flow rate, the suction hole size, and the number of suction holes are tested. The flow and concentration in the toilet bowl are numerically visualized. In addition, experimental results are in good agreement with the numerical results. Finally, the best conditions, a combination of the suction hole size of 4 × 4 mm2 and rear two pairs open are obtained. [Copyright &y& Elsevier]

Highlights: [•] Equivalency between different methods for fecal indicator bacteria enumeration was determined. [•] C. perfringens proved to be a valuable additional indicator of fecal pollution. [•] Salinity appeared to be the best predictor of a higher microbial load. [•] Use of historical microbiological data is preferred for determination of bathing water profile. [ABSTRACT FROM AUTHOR]

The article presents a study on the long-term effects of Class B biosolids on microbial organisms. It says that the study aims to determine microbial indicator organisms and pathogens in the original biosolids and to assess the potential for soil microbial activity with the use of microbial transformations such as nitrification, sulfur oxidation, and dehydrogenase. Land application has been studied in several studies including one which shows the governance of complex soil and environmental variables to the decay and survivability of microbial organisms. The presented study evaluates the potential benefits and hazards of land application by analyzing surface soil samples. Results show sustainability of land application during 20 years in relation with solid microbial properties.

Oxidative stress enzymes, superoxide dismutase (SOD), catalase (CAT), and ATPase, from two Gram-positive bacteria and one Gram-negative bacterium, respectively, were tested for response to the oxidative stress caused by bensulfuron-methyl (BSM). Native PAGE was used to detect the SOD isoenzyme profiles of these bacteria. All three bacteria possessed a basal level of SOD, CAT, and ATPase activity prior to being exposed to BSM. Enzyme activities changed in a BSM-concentration-dependent manner after exposure to BSM for 24h. Activity of all the enzymes was increased and reached the first activity peak after being exposed to BSM at 1 or 1.5h, respectively, then a decline occurred, and after that another simulation appeared at 9h or 14h. Only one and three detectable SOD isoenzyme bands were observed in Gram-positive strains and the Gram-negative strain, respectively. BSM could bring short-term ecotoxicity to three bacteria, but the effect of BSM was not lethal. [Copyright &y& Elsevier]

The article presents a study which uses a modified virus-dilution method in estimation of viral lysis and protozoan grazing on bacterial mortality. It compares modified virus-dilution method with the standard dilution protocol. It also aims to verify influence of the absence of lytic parameter in the standard protocol. Collected seawater samples from the coastal waters of Hokkaido, Japan were subjected to epifluorescence microscopy in the enumeration of microbes. It presents the advantages of modified virus-dilution technique synonymous to the standard dilution technique. It shows that the use of standard dilution protocol might underestimate instantaneous growth rate especially on pelagic systems where lytic pressure is relatively high.

The article discusses contributions the Medieval Spanish brought to the Western Hemisphere. The author talks about Spanish religious, military, and civil institutions brought to the West, as well as their material culture. The impact this material culture had on Texas is examined. Material culture discussed in the article includes domesticated plants, animals, and microbes. How these microbes changed Old World plants and domesticated animals is examined. The article also discusses how the Native Americans adopted to these changes and assimilated them into their own culture.

Five stations were established in the Fenglin mangrove area of Xiamen, China to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) and the numbers of PAH-degrading bacteria in surface sediments. Assessing the biodegradation potential of indigenous microorganisms and isolating the high molecule weight (HMW)–PAH degrading bacteria was also one of the aims of this work. The results showed that the total PAH concentration of sediments was 222.59ngg−1 dry weight, whereas the HMW–PAH benzo(a)pyrene (BaP) had the highest concentration among 16 individual PAH compounds. The variation in the numbers of PAH-degrading bacteria was 2.62×102–5.67×104 CFUg−1 dry weight. The addition of PAHs showed a great influence in increasing the microbial activity in mangrove sediments. A bacterial consortium, which could utilize BaP as the sole source of carbon and energy, and which was isolated from mangrove sediments and enriched in liquid medium for nearly one year degraded 32.8% of BaP after 63 days incubation. [Copyright &y& Elsevier]

Loss of nitrogen from the soil-plant system has raised environmental concern. This study assessed the fluxes of nitrous oxide (N2O) in the subsurface flow constructed wetlands (CWs). To better understand the mechanism of N2O emission, spatial distribution of ammonia-oxidizing bacteria (AOB) in four kinds of wetlands soil were compared. N2O emission data showed large temporal and spatial variation ranging from −5.5 to 32.7mg N2Om−2 d−1. The highest N2O emission occurred in the cell planted with Phragmites australis and Zizania latifolia. Whereas, the lower emission rate were obtained in the cell planted with P. australis and Typha latifolia. These revealed that Z. latifolia stimulated the N2O emission. Transportation of more organic matter and oxygen for AOB growth may be the reason. The study of AOB also supported this result, indicating that the root structure of Z. latifolia was favored by AOB for N2O formation. [Copyright &y& Elsevier]

Abstract: Batch experiments were conducted to characterize the degradation of benzo[a]pyrene, a representative high molecular weight (HMW) polycyclic aromatic hydrocarbon (PAH), by Sphingomonas yanoikuyae JAR02. Concentrations up to the solubility limit (1.2μg l−1) of benzo[a]pyrene were completely removed from solution within 20h when the bacterium was grown on salicylate. Additional experiments with [14C]7-benzo[a]pyrene demonstrated 3.8% mineralization over 7days when salicylate was present is solution, and one major radio-labeled metabolite was observed that accounted for ∼10% of the initial radio-label. Further characterization of the radio-labeled metabolite using HPLC/MS and HPLC/MS/MS identified radio-labeled pyrene-8-hydroxy-7-carboxylic acid and unlabeled pyrene-7-hydroxy-8-carboxylic acid as novel ring-cleavage metabolites, and a benzo[a]pyrene degradation pathway was proposed. Results indicate that biostimulation of HMW PAH degradation by salicylate, a water-soluble, non-toxic substrate, has significant potential for in situ bioremediation. [Copyright &y& Elsevier]

Abstract: Burkholderia cepacia is regarded as a genetically distinct but phenotypically similar bacteria group referring to Burkholderia cepacia complex (Bcc), which is found not only in clinic but also in rice growing environment. It is very important in microbial safety of rice for us to understand the genomovar status of Bcc. Genomovar analysis was performed among 87 Bcc isolates by means of Hae ?-recA RFLP assays and species-specific PCR tests. Three genomovars were found from the rice rhizosphere including?, ?B and ?, and genomovar ? was predominant. Genomovars?, ?A and ?B existed in the clinical samples, and genomovar ?A was the most popular. It showed that genomovar composition was different between the Bcc strains from the rice rhizosphere and clinical environment. Simultaneously, the results revealed the genetic diversity of Bcc strains from the rice rhizosphere, and genomovar ? referred as virulent species in clinic also existed in the rice rhizosphere. [Copyright &y& Elsevier]

The article discusses the various organisms that live in the soil. The author mentions that according to Brian McSpadden Gardener, plant pathologist at the Ohio State University with the Ohio Agricultural Research and Development Center, it would be an advantage to learn and understand how the soil works and soil organisms. Gardener has emphasized the importance of soil organisms, as the living things that move the nutrients in the soil. It also discusses the seven soil organisms responsible for the nutrient circulation of soil, including bacteria, fungi, and protozoa.