soil microbiology and microbial growth
Microbiology and Process Analysis laboratory
25/10/2013
Group 1
Microbiology laboratory
Abstract
The lab exercises were divided into three different analysis; microscopy, soil microbiology and bacterial growth.
The main aim of laboratory work with Escherichia coli and soil sample was to introduce students to bacterial growth in pure culture and soil microbial flora. The experiment of bacterial growth in pure culture using optical density measurement, plate count and DAPI direct count, showed that Plate Spread method was more precise to understand bacterial population growth tendency and counting generation time. During laboratory work with soil sample were determined relative number of bacteria, Actinomycetes and molds. Results showed, that more abundant specie in soil sample were Actinomycetes and least abundant – molds.
Samples of bacterial DAPI, wastewater flocculum and lake water were studied with a microscope in order to identify E. coli, filaments and phytoplankton for further analysis. A total of 5.72 x 106 E. coli bacteria were determined of the microscopy filter giving the first point on a growth curve. The growth curve suggests the bacteria entering their stationary growth phase with a flattening curve. Water from two sewage treatment plants, Vik and Grødaland was analysed, with Grødaland water containing a large amount of filaments. Phytoplankton diversity was compared between Stokkavannet andHålandsvannet, with Stokkavannet being most diverse as expected.
1. Introduction
1.1. Soil Microbiology and bacterial growth
The main purpose of this laboratory exercise was to study the growth of a bacterial population in pure culture using optical density measurement, plate counts using spread plate method. Also there were taken samples for direct counts that were carried out during the Microscopy laboratory exercise. Experiment with soil was done to determine the relative number of
25/10/2013
Group 1
Microbiology laboratory
Abstract
The lab exercises were divided into three different analysis; microscopy, soil microbiology and bacterial growth.
The main aim of laboratory work with Escherichia coli and soil sample was to introduce students to bacterial growth in pure culture and soil microbial flora. The experiment of bacterial growth in pure culture using optical density measurement, plate count and DAPI direct count, showed that Plate Spread method was more precise to understand bacterial population growth tendency and counting generation time. During laboratory work with soil sample were determined relative number of bacteria, Actinomycetes and molds. Results showed, that more abundant specie in soil sample were Actinomycetes and least abundant – molds.
Samples of bacterial DAPI, wastewater flocculum and lake water were studied with a microscope in order to identify E. coli, filaments and phytoplankton for further analysis. A total of 5.72 x 106 E. coli bacteria were determined of the microscopy filter giving the first point on a growth curve. The growth curve suggests the bacteria entering their stationary growth phase with a flattening curve. Water from two sewage treatment plants, Vik and Grødaland was analysed, with Grødaland water containing a large amount of filaments. Phytoplankton diversity was compared between Stokkavannet andHålandsvannet, with Stokkavannet being most diverse as expected.
1. Introduction
1.1. Soil Microbiology and bacterial growth
The main purpose of this laboratory exercise was to study the growth of a bacterial population in pure culture using optical density measurement, plate counts using spread plate method. Also there were taken samples for direct counts that were carried out during the Microscopy laboratory exercise. Experiment with soil was done to determine the relative number of
References: 2. Wikipedia: October 28, 2012, URL:http://en.wikipedia.org/wiki/Bacterial_growth. 5. Google images from Virginia Polytechnic Institute (2012) 6 7. Donnenberg, M.S and Kaper, J.B.(1992) Enteropathogenic Escherichia coli. Infect. Immun. October 1992 vol. 60 no. 10 3953-3961. 8. University of Waikato (2012) Resolving power of microscopes, Link to article: [http://www.sciencelearn.org.nz/Contexts/Exploring-with-Microscopes/Sci-Media/Images/Resolving-power-of-microscopes] . 9. Google images from Virginia Polytechnic Institute (2012) Link to image:http://www.files.chem.vt.edu/cheed/imaging/graphics/microsco.gif 10 11. MET160 Lab notes, 2012. 12. Environmental Leverage (2011) What are filaments, Link to article: [http://www.environmentalleverage.com/What_are_filaments.htm] 13 14. National Oceanic and Atmospheric Administration (NOAA) (2012) Phytoplankton are microscopic marine plants, Link to article:[http://oceanservice.noaa.gov/facts/phyto.html. 15. IVAR (2011) Regionale renseanlegg (NOR), Link to article: [http://www.ivar.no/regionale-renseanlegg/category619.html 16