This article elucidates that strain Pseudomonas aeruginosa (IES-Ps-1) is a versatile toxic organic compound degrader. With the degradation of malathion and cypermethrin (studied by other researchers previously), this strain was able to degrade phenol. Two other indigenous soil flora (i.e., Pseudomonas sp. (IES-S) and Bacillus subtilis (IES-B)) were also found to be potential phenol degraders.Phenol was degraded with Monod kinetics during growth in nutrient broth and mineral salts medium. Before entering into the growth inhibition phase, strains IES-Ps-1, IES-S and IES-B could tolerate up to 400, 700 and 500 mg/L phenol, respectively, when contained in nutrient broth. However, according to the Luong–Levenspiel model, the growth of strains IES-Ps-1, IES-S and IES-B would cease at 2000, 2174 and 2190 mg/L phenol, respectively. Strain IES-Ps-1 degraded 700, 900 and 1050 mg/L phenol contained in mineral salts medium with the specific rates of 0.034, 0.075 and 0.021 h−1, respectively. All these strains grew by making clusters when exposed to phenol in order to prevent damages due to high substrate concentration. These strains transformed phenol into catechol, which was then degraded via ortho-cleavage pathway.

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The vitreous antibodies may be involved in neutrophil-mediated opsonophagocytosis leading to 'spontaneous sterility' of the bacteria, and may play a role in the immunopathogenesis of staphylococcal endophthalmitis in the rat.

A pure bacterial culture able to utilize 2-fluorophenol (2-FP) as sole carbon and energy source was isolated by selective enrichment from sediments collected from a contaminated site in Northern Portugal. 16S rRNA gene analysis showed that the organism (strain FP1) belongs to the genus Rhodococcus. When grown aerobically on 2-FP, growth kinetics of strain FP1 followed the Luong model. An inhibitory effect of increasing 2-FP concentrations was observed with no growth occurring at 2-FP levels higher than ca. 4 mM. Rhodococcus strain FP1 was able to degrade a range of other organofluorine compounds, including 2-fluorobenzoate, 3-fluorobenzoate, 4-fluorobenzoate, 3-fluorophenol, 4-fluorophenol, 3-fluorocatechol, and 4-fluorocatechol, as well as chlorinated compounds such as 2-chlorophenol and 4-chlorophenol. Experiments with cell-free extracts and partially purified enzymes indicated that the first step of 2-fluorophenol metabolism was conversion to 3-fluorocatechol, suggesting an unusual pathway for fluoroaromatic metabolism. To our knowledge, this is the first time that utilization of 2-FP as a growth substrate by a pure bacterial culture is reported.

Fluorinated organic compounds are of growing industrial importance, with applications such as agrochemicals, pharmaceuticals, and performance materials (23,24,28,41). The safe use of such compounds, as well as appropriate disposal and treatment of wastes, will benefit from knowledge about their biodegradation. However, little information is available about the microbial metabolism of fluorinated organic compounds compared to other halogenated chemicals. Most studies on the bacterial degradation of fluorinated organics describe fluorobenzoic acids, which under aerobic conditions can be converted into the corresponding fluorocatechols (3, 17, 33). Papers about the degradation of fluorophenols have also appeared (11,25,51).4-Fluorocinnamic acid (4-FCA) is used in industry for the synthesis of flavors and pharmaceuticals (8), and polymers of 4-FCA are applied in electronics (14). It was proposed that under aerobic conditions in nonacclimated industrial activated sludge, 4-FCA could be converted into 4-fluorobenzoic acid (4-FBA) via the formation of 4-fluoroacetophenone (4-FAP) (8, 32). In another study, using activated sludge from a wastewater treatment plant, 4-FCA was suggested to be transformed into an epoxide that is converted to 4-FAP. This compound would then be converted into 4-FBA, but no products were detected from the breakdown of 4-FBA (5).The conversion of nonhalogenated cinnamic acids to benzoic acids, such as the transformation of ferulic acid to vanillic acid, has been described previously (2,4,20,31,39). Cinnamic acid, coumaric acid, and ferulic acid are transformed by Streptomyces setonii (47) and Rhodopseudomonas palustris to benzoic acid or the corresponding derivatives (19). Alcanivorax borkumensis MBIC 4326 (9) and Papillibacter cinnamivorans (7) transformed cinnamic acid into benzoic acid. The metabolism of these compounds thus proceeds with side chain degradation prior to ring cleavage. Side chain degradation is carried out either by ␤-oxidation or by direct deacetylation mechanisms, which leads to elimination of two carbon units from the unsaturated side chain in bacteria, yeasts, and fungi (40).Since no clear information on the degradation route of 4-FCA is available, we have isolated two pure bacterial strains to study the complete microbial metabolism of the compound, and in this paper, we propose a degradation pathway. MATERIALS AND METHODSGrowth conditions. Cells of strains G1 and H1 were grown aerobically at 30°C under rotary shaking or in a fermentor. Growth medium (MMY) contained (per liter) 5.37 g of Na 2 HPO 4 ⅐ 12H 2 O, 1.36 g of KH 2 PO 4 , 0.5 g of (NH 4 ) 2 SO 4 , and 0. Enrichment and isolation of 4-FCA-and 4-FBA-degrading organisms. Soil samples collected from a site in the Netherlands contaminated mainly with chlorobenzene and halogenated aliphatic compounds were used as the initial inocula for the 4-FCA and 4-FBA enrichment cultures. Flasks contained 40 ml MMY and 5 mM 4-FCA or 5 mM 4-FBA as the sole source of carbon and energy. The cultures were incubated at room temperatur...

Arthrobacter sp. strain G1 is able to grow on 4-fluorocinnamic acid (4-FCA) as sole carbon source. The organism converts 4-FCA into 4-fluorobenzoic acid (4-FBA) and utilizes the two-carbon side-chain for growth with some formation of 4-fluoroacetophenone as a dead-end side product. We also have isolated Ralstonia sp. strain H1, an organism that degrades 4-FBA. A consortium of strains G1 and H1 degraded 4-FCA with Monod kinetics during growth in batch and continuous cultures. Specific growth rates of strain G1 and specific degradation rates of 4-FCA were observed to follow substrate inhibition kinetics, which could be modeled using the kinetic models of Haldane–Andrew and Luong–Levenspiel. The mixed culture showed complete mineralization of 4-FCA with quantitative release of fluoride, both in batch and continuous cultures. Steady-state chemostat cultures that were exposed to shock loadings of substrate responded with rapid degradation and returned to steady-state in 10–15 h, indicating that the mixed culture provided a robust system for continuous 4-FCA degradation.

This study has been conducted to identify the correlation between food and aluminum intoxication through leaching. The ingestion is the main route of Aluminum exposure to the human body. Hence it is necessary to identify the aluminum levels in human body leached out from aluminum wares and aluminum foil. Pieces of chicken and red meat were baked with different types of solutions containing tomato juice, fresh yoghurt, salt and vinegar in different combinations, they were wrapped in aluminum foil in different combinations, marinated in aluminum pan and were tested for the pH and weight of pieces and foil. The result showed that citric acid with combination of lactic acid becomes the source for elevated level of aluminum in food items especially in raw beef. Citric acid with combination of tomato juice had highest accumulation rate than other solutions i.e 292.25mg/Kg in beef, while chicken leaching rate was 209.52mg/kg by the combination of yogurt and lemon juice. The fact still remains that once aluminum exceeds the acceptable limit from daily ingestion of food cooked in these pots, coupled with other sources from the environment. This environmental factor may contribute in increase of neurodegenerative diseases. The aim of this research study is to detect leaching out of aluminum levels from aluminum foil in different food solutions as it is becoming a common practice.

We report a simple route to synthesized erosion resistant epoxy-based nanocomposite coatings. The silica nanoparticles were surfaced modified using stearic acid and then incorporated into the epoxy coating. The resulting nanocomposite coating films were characterized for erosion resistance, mechanical and thermal stability. For the application on turbine blades, conventional techniques were used. It was found that for the incorporation of nano silica into the epoxy matrix, surface modification was essential. Besides, incorporation of silica resulted in considerable improvement in the resistance to erosive wear and a life span improvement of around 36 percent was achieved. Similar trend was observed for the Shore D hardness which increases from 60 for the virgin coating to 70 for the nanocomposite coating.