Microbiological activity

Marecek and colleagues developed a new electrochemical method for the rapid quantitative analysis of the antibiotic monensin in the fermentation vats used during its production. The standard method for the analysis, which is based on a test for microbiological activity, is both difficult and time-consuming. As part of the study, samples taken at different times from a fermentation production vat were analyzed for the concentration of monensin using both the electrochemical and microbiological procedures. The results, in parts per thousand (ppt), are reported in the following table. 

Industrial antimicrobial agents are chemicals used to prevent the adverse consequences of microbiological activity in processes and products. Some are unique to this segment and others are drawn from the antimicrobial agents used in medicine, agriculture, and sanitary appHcations. Industrial antimicrobials are selected where process or stricdy physical conditions, such as irradiation or heat, are impractical or ineffective in controlling microbiological activity. 

R " = CH3) which has activity similar to that of clavulanic acid and inhibits many of the type I Cephases. The synthesis (156), microbiological activity (152,156—162), and stabiUty (152) of ta2obactam have been reported. 

At this point in the investigation, the relationship between the pits and the arrowhead-shaped regions of corrosion was uncertain. Several possible causes for the pitting were considered, such as siphonic gas exsolution, biological and/or microbiological activity, and debris (concrete chips, etc.) lodged in the tubes, but each was tentatively dismissed as improbable since none of the proposed mechanisms adequately accounted for all observations. 

Although viral infections are important causes of both otitis media and sinusitis, they are generally self-limiting. Bacterial infections m complicate viral illnesses, and are also primary causes of ear and sinus infections. Streptococcus pneumoniae and Haemophilus influenzae are the commonest bacterial pathogens. Amoxycillin is widely prescribed for these infections since it is microbiologically active, penetrates the middle ear, and sinuses, is well tolerated and has proved effective. 

Botz, E, Nagy, S., and Kocsis, B. Detection of microbiologically active compounds, m Planar Chromatography, Nyiredy, Sz.,lid., Springer Scientific, Budapest, Hungary, 2001. pp. 489-516. 

HCHO/aldehyde free a Broader microbiological activity spectrum than BIT... 

The partial pressure of C02 in the soil air controls the concentration of both dissolved C02 and undissociated carbonic acid. At 0.003 atm of C02 (g) as a reference level for soils, [H2C03°] is about 1.04 x 10 4 M (Lindsay, 1979). At a normal atmospheric level of 0.0003 atm C02 (g), [H2C03°] is approximately 1.04 x 10 5 M. In most soils, C02 (g) is higher than in the atmosphere. C02 is released from soil and plant root respiration. In flooded soils, C02 (g) partial pressure increases to 0.01-0.3 atm, about 1000-fold higher than normal upland soils due to strong microbiological activity (Lindsay, 1979). 

Traditionally, butter was made by allowing cream to separate from the milk by standing the milk in shallow pans. The cream is then churned to produce a water in oil emulsion. Typically butter contains 15% of water. Butter is normally made either sweet cream or lactic, also known as cultured, and with or without added salt. Lactic butter is made by adding a culture, usually a mixture of Streptococcus cremoris, S. diacetylactis and Betacoccus cremoris. The culture produces lactic acid as well as various flavouring compounds, e.g. diacetyl, which is commonly present at around 3 ppm. As well as any flavour effect the lactic acid inhibits any undesirable microbiological activity in the aqueous phase of the butter. Sweet cream butter has no such culture added but 1.5 to 3% of salt is normally added. This inhibits microbiological problems by reducing the water activity of the aqueous phase. It is perfectly possible to make salted lactic butter or unsalted sweet cream butter if required. In the UK most butter is sweet cream while in continental Europe most butter is lactic. 

There is a need to measure the activities of enzymes and to correlate these measured activities with microbial diversity in soil. It is conceptually wrong to assume a simple relationship between a single enzyme activity and microbiological activity in soil (Nannipieri et al. 2003). Most of the assays used to determine microbiological activities in soil present the same problem measuring potential rather than real activities (Nannipieri et al. 1990). Indeed, assays are generally made at optimal pH and temperature and at saturating concentration of substrate. Furthermore, synthetic rather than natural substrates are often used, and soil is incubated as a slurry (Nannipieri et al. 1990). 

Nl). This line of inquiry is likely to become more active if the unconjugated pteridine, biopterin, proves to have the proper microbiological activity and so can serve as standard. 

Blood of normal subjects was obtained from an antecubital vein, diluted 1 5 with pH 4.5 buffer,2 and autoclaved 30 minutes to convert bound cobalamin into its microbiologically active form serum was treated like blood. This procedure allowed estimation of total vitamin Bi2. For the subsequent inoculation of specimens (a) E. coli as a loopful from nutrient agar suspended in 25 ml of medium, (b) L. leichmannii, an 18-hour culture diluted 1 10 in basal medium, (c) E. gracilis, strain Z, and (d) O. malhamensis are inoculated directly from a 5-day culture grown in liquid maintenance medium. One drop into a culture flask served as inoculum. The bacteria required 18-hours for full growth protozoa, 4-5 days. 

Heterotrophic and autotrophic bacteria are important participants in the restoration industry. Both types are indigenous to almost every site. The subsurface environment includes many thousands of species of microbes, which act in harmony to support each other. Waste products from one group become nutrients for another. When free oxygen is depleted, anaerobic activity increases. Thus, it is often convenient to consider microbiological activity as a series of processes resulting from bacterially mediated oxidation-reduction reactions. 

Soil pH Soil pH should be in the range of 6 to 8, to maintain cell turgidity and promote enzymatic reactions. Soil buffers, such as carbonate minerals, can be valuable in neutralizing acidic groundwaters as a result of high C02 concentrations because of microbiological activity. 

L. V. Nielsen, The Effect of Cathodic Protection and Microbiological Activity on Hydrogen-Related Cracking in Steel, PhD thesis. The Technical University of Denmark, 1995. 

Primary minerals with low surface area (e.g., sihca minerals) and low reactivity mainly affect the physical transport of water, dissolved chemicals, colloids, immiscible (in water) liqnids, and vapors. Secondary minerals generally have high surface area (e.g., clay minerals) and high reactivity that affect the transport of chemicals, their retention and release onto and from the solid phase, and their surface-induced transformations. The sohd phase also can indirectly induce the degradation of chemical compounds, through its effects on the water-air ratio in the system and, thus, on microbiological activity. 

The composition and reactivity of the liquid phase (known as the soil solution) is defined by the quality of the incoming water and affected by fluxes of matter and energy originating from the vicinity of the solid phase, microbiological activity, and the gas phase. To understand the properties of the subsurface hquid phase, it is first necessary to consider the structure of the water molecule. 

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