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91 Uppsatser om Allelopathy bacterial - Sida 1 av 7

Koncentrisk hämning och stimulans av bakterietillväxt i agarkulturer

The aim of this study is to elucidate factors that effect growth of Sarcina lutea and Bacillus subtilis, exposed to the growth inhibitor SDS (Sodiumdodecylsulfat). Agar diffusion experiments revealed repeated, concentric zones of inhibition and stimulation upon exposure to Sodiumdodecylsulphate or to Amoxicillin. Temperature, nutrient concentration and inhibitor concentration were controlled. Formation of successively repeated zones of inhibition, stimulation, inhibition and stimulation is discussed: ? The extension of the primary inhibition zone is due to the concentration of applied Sodium dodecyl sulphate.? Immediately outside the primary inhibition zone the bacteria have access to diffusing nutrients that have not been consumed in the primary inhabitation zone.? In zones of dense bacterial growth the bacteria may produce inhibiting substances, affecting growth of bacteria in adjacent zones.? In zones of dense bacterial growth the nutrients will soon become depleted, thus affecting bacteria in adjacent zones..

Preoperativ hud- desinfektion

Introduction. Infection Prevention is one of the surgical nurses' main responsibilities. One of the steps which patients undergo in this purpose before surgery is the preoperative skin desinfektion. Background. The patient washes the day before surgery with Descutan cutaneous sponge 4 %, a sponge containing chlorhexidine.

Bakteriell produktion i humösa istäckta sjöar i norra Sverige

The main purposes of this study were to 1) quantify bacterial production in winter during ice conditions, and 2) to compare these production measures with values measured from summer and open water conditions in three humic lakes situated in northern Sweden. Another purpose of this study was to 3) examine whether clear-cutting significantly affected bacterial production or water chemistry in two lakes situated in catchments were a large part of the forest had been removed through logging compared to an undisturbed reference lake. In winter (March/April 2014), the bacterial production ranged from 0, 7 - 2, 2 µgC/L/day and in the summer of 2013 the production values was 4 ? 10 times higher. The main reason for lower bacterial production in winter was ascribed to lower water temperatures as well as to older and more recalcitrant DOC, as there were no significant differences in total dissolved nitrogen or DOC concentration or -quality, that could explain a lower production compared to summer.

Bakterietillväxt i strömedel till mjölkkor

The resting area is the most important place in the barn for the dairy cow, sometimes called the heart of the free stall system. Inadequate design of the lying area, and lack of or poor quality of bedding materials may reduce the hygiene of the stall. Poor management regarding the cleanliness of the resting area may lead to poor animal hygiene and increased bacterial growth. This in turn will lead to increased risk for environmental mastitis as well as impairing milk quality through contamination with spores. In this literature study the most commonly used bedding materials; straw, sawdust, wood shavings, clean sand, recycled sand, peat and recycled manure solids, are compared to one another with regards to their ability to resist bacterial growth. Effects of adding hydrated lime to bedding materials have also been studied. Most bacteria need humidity and prefer a quite high water activity to be able to grow.

Probiotika som prevention mot urogenitala sjukdomar

About 10 % of the adult women population in Sweden are treated annually for urinary tract infections. The increasing bacterial resistance towards antibiotics is classified by WHO (World Health Organization) and ECDC (European Centre for Disease Prevention and Control) as one of the greatest treats for human health in a global perspective. To find alternatives scientists are studying the possibility to use probiotics to reduce the frequency of recurring urinary tract infections. This literature study examines five randomized double blinded placebo controlled studies where different strains of Lactobacillus have been used as a prophylactic to women suffering from recurrent urinary tract infections and bacterial vaginosis. Overall the studies do not display enough promising results to recommend the use of probiotics as a prophylax or cure..

Evaluation of a selective media for the detection of gram-positive bacteria in leg ulcers and pressure wounds

Hard-to-heal ulcers are resource intensive due to the fact that they are difficult to treat and especially vulnerable to bacterial invasion. The bacterial culture contaminating these wounds often consist of several different bacterial organisms that originate from endogenous sources. Necrotic material in ischemic ulcers provide nutrition which support bacterial reproduction, increasing the risk of infection. Determining causative pathogen in infected ulcers proves to be difficult when culturing swab samples, however Staphylococcus aureus and hemolytic streptococci generally act as primary pathogens.    The aim of the study was to investigate if the detection rate increased for S. aureus and hemolytic streptococci when culturing swab samples from ulcers on Columbia CNA; a media selective for gram-positive bacteria.

Side effects of biological control agents in agriculture : does the bacteria Bacillus amyloliquefaciens affect the earthworm Aporrectodea longa?

Pathogenic microorganisms pose a big threat towards food production. Meanwhile, negative impacts on humans and environment are seen by the use of pesticides. Biological control agents are an alternative to the use of chemical pesticides, and plant-growth promoting rhizobacteria, such as Bacillus amyloliquefaciens has been shown to have good properties as biocontrol agents. Before these bacteria can be used commercially their impact on other soil organisms has to be evaluated. This thesis looks into what biocontrol bacteria are and how they might affect earthworms.

Tarmflorans påverkan på fetma

Obesity is a problem that increases exponentially in humans and companion animals. It is defined as a big accumulation of fat in the body and is usually connected with several diseases. This study describes how obesity can be diagnosed, in which way the gut flora can affect obesity, if the gut flora is genetically influenced or not, and how it differs between individuals with obesity and obesity-related diseases. Conclusions of the study are that both the bacterial strains Bacteriodetes and Firmicutes probably have a connection to obesity. The intestinal flora is probably also genetically related.

Cleaning process of abattoir wastewater with focus on bacterial pathogens

This study was conducted at the City Abattoir in Kampala, Uganda to evaluate the cleaning process, with focus on bacterial pathogens, in a pilot scale integrated bioprocess. This consisted of four steps: anaerobic sequencing batch reactors; aerobic/anoxic sequencing batch reactors; a high performance temperature controlled methanogenesis digester and a constructed wetland. The objective was to determine if this type of cleaning process could be used to clean wastewater from abattoirs in a satisfactory way. The indicator organisms for faecal contamination, Escherichia coli and Enterococcus spp. were used to investigate in what numbers bacteria could be found in the untreated wastewater and how much that was reduced in the different steps of the cleaning process. The water was analysed for Salmonella to see if human pathogens could be found and could survive the different steps of the treatment process.

Bacterial contamination of eggshells in deep litter floor systemsand conventional cages in Jordan

This study was carried out in Jordan with the purpose to investigate the bacterial microflora of egg shells from cage systems and from deep litter floor systems. Another aim wasto get a general impression of the hygiene, at farm level, of egg production in Jordan andthe factors affecting it.Eggs from two cage systems and three floor systems were analyzed, regarding bacterialcontamination of the egg shells. Egg samples were taken from the storage room, the eggcradle in the cage system and from the nest and floor in the floor system. To get a generalimpression of the hygiene at the farms, swab tests and air tests were performed. Swab testswere performed with a sterile cotton swab at the same units as the eggs were sampled andair tests were performed by opening petri dishes where the hens were staying.

Effekt av myrsyra och beta-laktamas på penicillin- och S. aureus-halt i mjölk till kalvar :

A sample of milk inoculated with S. aureus was treated with penicillin, and Antipen (a new commercial product containing penicillinase) was added. To another sample with S. aureus and penicillin, formic acid to pH 5 was added, and to yet another sample, a combination of formic acid and Antipen was added. Controls with no penicillin were treated in the same way.

Development of new food products with components active against Helicobacter pylori - with purpose to improve gastric health in humans

Gastric and intestinal disorders are common and costly human health problems worldwide. Helicobacter pylori are a gram-negative, pathogen bacteria and the most common cause of duodenal and gastric ulcer in the stomach the intestinal mucosa. Prolonged infection and colonization can lead to chronic gastritis and stomach cancer. H. pylori are present in the gastric and intestinal mucosa of half of the world population and a relation between infection and low socioeconomic status has been shown.

ATP bioluminescence to establish a test procedure for hygiene testing of liners and tubes on farm level : an investigation of the effect of ageing on the hygienic status of rubber liners and tubes

When rubber equipment in a milking system ages, physical and chemical deterioration occurs and cracks, crevices, as well as deposits of organic and inorganic material is formed on the surface. Bacterial colonization can accumulate, especially on ageing rubber equipment and if the cleaning procedure is not functioning properly. Formation of biofilm in milking equipment could in turn cause bacterial contamination of bulk tank milk. ATP bioluminescence is a fast and easy way to determine the hygienic status of a surface based on its ATP content, and results are given in relative light units (RLU). The method measures both bacterial contamination as well as residues from other organic material.

Medveten måltid : Ett begrepp i förändring

The key elements of sourdough fermentation are the presence of active lactic acid bacteria (LAB) and yeast. Sourdough fermentation originates from the ancient Egypt. One theory concerning its onset states that a portion of bread dough was set aside to be baked at a later date and started to ferment spontaneously.Sourdough may contain a wide variety of microorganisms, mainly dominated by LAB and yeast. There are over 50 species of LAB that has been identified in various sourdoughs and more than 20 species of yeast. Sourdough fermentation has been shown to have various impacts on baked cereal good, most of which are attributed to LAB.This study addresses some effects of LAB from fermented milk products in sourdough and sourdough bread.

Hotell och värdskapsprogrammet : Branschens uppfattningar och förväntningar

The key elements of sourdough fermentation are the presence of active lactic acid bacteria (LAB) and yeast. Sourdough fermentation originates from the ancient Egypt. One theory concerning its onset states that a portion of bread dough was set aside to be baked at a later date and started to ferment spontaneously.Sourdough may contain a wide variety of microorganisms, mainly dominated by LAB and yeast. There are over 50 species of LAB that has been identified in various sourdoughs and more than 20 species of yeast. Sourdough fermentation has been shown to have various impacts on baked cereal good, most of which are attributed to LAB.This study addresses some effects of LAB from fermented milk products in sourdough and sourdough bread.

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