Methanotrophy, Methylotrophy, the Human Body and Disease

Methylotrophic Bacteria use one-carbon (C1) compounds as their carbon source. They have been known to be associated to the human body for almost 20 years as part of the normal flora and were identified as pathogens in the early 1990s in end-stage HIV patients and chemotherapy patients. In this chapter, I look at C1 compounds in the human body and exposure from the environment and then consider Methylobacterium spp. and Methylorubrum spp. in terms of infections, its role in breast and bowel cancers; Methylococcus capsulatus and its role in inflammatory bowel disease, and Brevibacterium casei and Hyphomicrobium sulfonivorans as part of the normal human flora. I also consider the abundance of methylotrophs from the Actinobacteria being identified in human studies and the potential bias of the ionic strength of culture media and the needs for future work. Within the scope of future work, I consider the need for the urgent assessment of the pathogenic, oncogenic, mutagenic and teratogenic potential of Methylobacterium spp. and Methylorubrum spp. and the need to handle them at higher containment levels until more data are available

Preparation of nanosilver via one-step chemical reduction in aqueous medium at elevated pressure

Otrzymywanie nanosrebra przeprowadzone zostało na drodzejednoetapowej redukcji chemicznej. Jako środek redukujący jonysrebra i stabilizujący nanocząstki zastosowano odpowiednio kwasaskorbinowy i żelatynę. Otrzymano zawiesinę nanosrebra charakteryzującąsię monomodalnym rozkładem wielkości cząstek i średnimich rozmiarem 5–125 nm.Nanosilver synthesis was carried out by a one-step chemicalreduction. Ascorbic acid and gelatin were used as reducing agentof silver ions and stabilizing factor of nanoparticles. Obtainednanosilver suspensions were characterized by monomodalparticle size distribution with their average size of 5–125 nm

Occupational exposure level of pig facility workers to chemical and biological pollutants

Objective. The aim of the study was to assess the impact of a fattening season on the level of airborne chemical and microbial pollutants in the pig fattening house. Materials and method. Evaluation of the air composition as well as the microbiological air quality were made during 2 series, i.e. in the summer and winter period of fattening. Airborne gaseous pollutants were analyzed by gas (organic compounds) and liquid (inorganic compounds) chromatography methods. Air microbial contamination was determined in compliance with the Polish Standard PN-EN 13098:2007. Results. The air/gas composition in the pig unit showed that irrespective of the fattening season, the level of determined pollutants – especially ammonia, volatile organic compounds (VOCs), including methanethiol and total dust – could have an adverse effect on the health of swine facility workers. The investigated pig building was found to be a source of chemical pollutants as well as biological agents. The total bacterial count in 1 m3 of air was 3.6×106 and 4.6×106 cfu, during the winter and summer periods of fattening, respectively. Gram-positive cocci predominated in both seasons. In the winter, fungi of the Trichoderma genus were represented equally often. In the summer period, up to 90% of the isolated fungus was Aspergillus spp. Conclusions. Workers engaged in swine rearing and production are occupationally exposed not only to a high concentration of microbial contamination, but also to irritating and odorogenous volatile compounds. Thus, activities directed at the promotion of health prevention strategies, as well as effective guidelines for safe and hygienic animal housing, should be implemented