Se ha estudiado dentro de la aplicaci.n de lodos de depuradora de aguas residuales al suelo, la influencia de la temperatura en la evoluci.n de la poblaci.n de aerobios totales y de microorganismos pat.genos de origen fecal, tales como coliformes fecales, Escherichia coli y estreptococos fecales, as. como la relaci.n entre el crecimiento o decrecimiento de dichas poblaciones con la variaci.n del pH, tanto en muestras de suelo sin lodo o de referencia, como en las muestras de suelo m.s lodo, durante un per.odo de incubaci.n de 80 d.as. Se ha trabajado en condiciones de laboratorio, manteniendo constantes tres temperaturas de incubaci.n diferentes (15, 25 y 35 grados C), y con un contenido de humedad constante en las muestras del 10%. Con este trabajo se ha visto que la temperatura y los d.as de incubaci.n, influyen considerablemente en la evoluci.n de las poblaciones microbianas estudiadas. Despu.s de los 20 primeros d.as de incubaci.n de las muestras en estas condiciones, las poblaciones de microorganismos pat.genos estudiados est.n por debajo de los l.mites de detecci.n. | It has been studied during the application of sewage sludge to the soil, the influence of temperature in the evolution of total aerobe microorganisms and faecal pathogen microorganisms such as faecal coliforms, Escherichia coli and faecal streptococcus and the connection between the growth and the decrease of this microbial population with pH, in soil samples with and without sewage sludge, over an incubation period of 80 days. Samples at laboratory conditions were maintained at incubation temperatures (15, 25 and 35 deg C) and moisture content (10%) constant. In this work it has been shown that the temperature and the incubation days have a great influence in the evolution of the microbial population. After 20 days of samples incubation at specified conditions, the faecal pathogen microorganisms are under detection limits.

One of the basic criteria for the determination of herbicide effect on a biological activity of soil is their influence on number of soil microflora. Ever increasing application of Simazine and Atrazine in contemporary agricultural production created the need for investigation of their influenece on microflora in soil and ability of microorganisms in soil to use them as a sole or additional source of carbon and nitrogen was also under examination. Our investigations indicated higher number and more successful growth of microorganisms originated from previously Simazine and Atrazine-treated soil comparing to untreated soil, grown on nutrient media. They used these herbicides as a sole or additional source of carbon, nitrogen or both of them. The number of microorganisms from Simazine-treated soil was greater than that of microorganisms from Atrazine-treated soil. There was a greater reduction in number of microorganisms as well as in their growth of the media containing Simazine, particularly Atrazine as a sole source of carbon in relation to nutrient media in which these herbicides served as a sole source of nitrogen. The least number of microorganisms as well as the lowest growth rate were recorded in treated, particularly untreated soils on a medium containing Simazine and Atrazine as a sole source of carbon and nitrogen. Yeast extract, as an additional source of biotic substances reduced amount of sucrose and NH4NO3 as additional sources of carbon and nitrogen, had a stimulus effect on incidence and growth of microorganisms both in treated and untreated soils.

Badano rozkład wielowarstwowego opakowania Tetra-Pack przez zespół mikroorganizmów mezofilnych. Biodegradację prowadzono w warunkach modelowych, w naturalnym środowisku glebowym, a także w glebie wzbogaconej w mieszaninę wyselekcjonowanych drobnoustrojów. Stwierdzono, że w grupie drobnoustrojów degradujących opakowanie dominują bakterie Bacillus coagulans i pleśnie Aspergillus niger. Efekty biodegradacji były wzmocnione przez dostęp drobnoustrojów do warstwy celulozowej opakowania oraz wzbogacenie gleby w aktywne mikroorganizmy amylolityczne i celulolityczne. | Decomposition of multilayer Tetra-Pack packaging by of mesophilic microorganisms was investigated. Biodegradation was carried out under model conditions, in the natural soil environment and also in the soil enriched with the mixture of selected microorganisms. It was found out that among the microorganisms able to degrade the packaging the most numerous are Bacillus coagulans and Aspergillus niger. Biodegradation effects were strengthtened due to microorganisms accessibility to the cellulose layer of the packaging and also due to soi I enriching with the active amylolytic and cellulolytic microorganisms.

To help us understand the factors and mechanisms implicated in the death of microorganisms or their resistance to temperature in a low water activity environment, microorganisms were dried on the surface of glass beads before being subjected to high temperatures for a short period followed by rapid cooling. Two microorganisms were studied: the yeast Saccharomyces cerevisiae and the bacterium Lactobacillus plantarum. Experiments were carried out at 150, 200, and 250°C, with four durations of heat treatment and seven levels of initial water activity between 0.10 and 0.70. We observed an unexpected range of water activity, between 0.30 and 0.50, at which microorganisms were more resistant to the various treatments, with maximal viability at 0.35 for L. plantarum and 0.40 for S. cerevisiae.

The purpose of this study was to develop a pilot scale bio-filter system removing ammonia gas with microorganisms. The system consisted of chaff a blower, a temperature sensor, a moisture sensor, a solenoid value, and a heating system. Temperature and moisture contents were controlled via a PC to provide the microorganisms with proper environment. The microorganisms used in this study were Bacillus . coagulans NLRI T-6 and Pseudononas. putida NLRI S-21 of bacilli. Performance tests were performed to evaluate gas removal rate during 20 days .

ABSTRACT: Cerrado soils are extremely old, highly weathered and depleted in essential nutrients, especially P. For this reason, the addition of P fertilizers is mandatory in order to obtain economical yields of annual crops. Soil microorganisms play a key role in the P cycle. The P immobilized in the soil microbial biomass acts as reservoir of this element. Soil microorganisms also produce enzymes that act in the P mineralization, participate in the solubilization of inorganic phosphorus and are able to form symbiosis with plants, denominated mycorrizha, enhancing the uptake of this element. In this review we discuss the results of several studies evaluating the use of soil microorganisms to increase P availability in soils, some of the difficulties related to field inoculation and the perspectives for future research.

Laboratory experiment was made to digest soybean oil using lipase enzyme and microorganisms. It was found that lipase enzyme digested soybean oil well at pH between 6.0-6.66. Besides this, stirring the mixture at 200 rpm 2 hours to blend and to increase oxygen in water helped give the best digestion efficency for lipase enzyme, but when sodium lauryl sulphate was added to lower the surface tension, the digestion decreased. Moreover, lipase enzyme powder could be directly used without the need to dissolve it in water first. The quantity of the enzyme would effect the digestion efficiency as well. The amount that best digested the 5 percent oil in synthesis wastewater was 2.5 percent : in other words, the ratio of enzyme to oil was 1:2. In the experiment, after the oil had been digested by lipase enzyme by stirring it for 2 hours, microorganisms should be added for further digestion. As a result, the oil was better digested than when just only enzyme or microorganisms were added. The digestion efficiency was significantly different from 12 hours on, and the amount of free fatty acid reached its maximum at the 36th hour after microorganisms had been added.