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Consequently this experiment consists of three parts: 1st part is about investigating the effect f temperature on microbial growth by varying the temperature range: ICC, ICC, ICC and ICC; 2nd part is directed to determine the effect of pH on growth of microorganisms by varying the pH ranges: pH, pH, pH, pH; the last part is about effect of oxygen requirement on growth of microbes, where the microorganisms grow depending on oxygen demand. Introduction: Microorganisms are classified depending on growth requirements.
In this laboratory the microorganisms are divided due to effect of temperature, pH and oxygen demand. The microorganisms are divided into three groups depending n temperature ranges they live: acropolises, anglophiles and thermopiles; inhabiting cold environment with optimal temperature for reproduction below ICC, living in temperature ranges between ICC to ICC and the last growing optimally at temperature above ICC respectively. The optimal temperature is the temperature that is best condition for growth of microorganisms as the enzymes they contain act most effectively at this temperature.
The second group of microorganisms investigated in this experiment is divided due to effect of pH on microbial growth. They divided to acidophilus(acid-loving) inhabiting the egging with pH below 4, neutralizes growing in pH range between 6. 5-7. 5 and the alkalizes (base-loving) grow at pH range above 9. Also the term optimal pH is used here as narcissism’s reproduce effectively at narrow pH range depending on activity of enzymes responsible for replication of DNA The last group of microorganism is divided into three categories depending on oxygen requirement into anaerobes and robes.
The anaerobes are subdivided further into facultative anaerobes, obligatory anaerobes and rattlebrain anaerobes: facultative are those that can reproduce in the absence of oxygen but grow effectively at the presence of oxygen, obligatory anaerobes are microbes that cannot reproduce in the presence of oxygen, even it is harmful for them and rattlebrain anaerobes are species that can grow in presence of oxygen, but do not benefit from it.
The microelectronic anaerobes are types of microorganisms that require oxygen for reproduction at low concentrations compared to obligate robes. Materials and Methods: 1st part Cue Trees 24- to 48-hour nutrient broth cultures of Escherichia coli, Bacillus coagulants, Pseudonymous cavitations, Seriate mercenaries, and Saboteurs broth culture of Chromosomes aggressive.
Media Per designated student group: four Triplicate soy agar plates and four Saboteurs broth tubes Equipment Bunsen burner, inoculating loop, refrigerator set at ICC, two incubators set at ICC and ICC, automatic pipette (20-200 VI), sterile tips for automatic pipette, test tube rack, and glassware marking pencil. 2nd part Saline suspensions of 24-hour nutrient broth cultures, adjusted to an absorbency (A) of 0,05 at a wavelength of 600 NM, of Allegiances fiscals, Escherichia coli, and Per designated student group: 12 Triplicate soy broth (TTS) tubes, three at each of the following pH designations: 3, 6, 7, and 9.
The pH has been adjusted with 1 N Noah or 1 N HCI Bunsen burner, sterile I-ml tips, automatic pipette (1000 Pl), spectrophotometer, 3rd part Cultures 24- to 48- hour nutrient broth cultures of Staphylococcus erasures, Allegiances fiscals; 48- to 72- hour Saboteurs broth cultures of Chromosomes aggressive Three brain heart infusion agar deep tubes per student group. Bunsen burner, Watergate, iced Watergate, thermometer, sterile automatic pipettes (200 Pl and 1000 VI), test tube rack, and glassware marking pencil. Procedure: Part 1. Temperature. ) All plates were divided into 4 quadrants with marker and labeled with name f appropriate organism. Each plate was labeled with definite temperature (ICC, ICC, ICC, or ICC) 2) Each of the species: E. Coli, B. Coagulants, P. Cavitations, and S. Mercenaries were inoculated into each plate using aseptic techniques. 3) Four Saboteurs broth tubes were labeled including temperature of incubation as indicated in step 2. 4) The S. Aggressive culture was shaken to suspend organisms. 5() Pl of the culture were transferred by automatic pipette into each of the four tubes of broth media. . All plates were incubated in an inverted position and the broth cultures at each of the four experimental temperatures (ICC, ICC, K, or ICC) for 24 to 48 hours. Part 2. PH 1 . Using a pipette, a series of the appropriately labeled TTS tubes of media were inoculated, pH values of 3, 6, 7, and 9, with E. Coli by adding O, 1 ml of the saline culture to each. 2. Step 1 for the inoculation of A. Fiscals and S. Aggressive was repeated, using a new sterile tip each time. 3. The A. Fiscals and E. Coli cultures for 24 to 48 hours at ICC and the S. Revisal cultures were incubate for 48 to 72 hours at ASK. 1 . Using the spectrophotometer the absorbency of all cultures determined. The readings where recorded in the chart provided in the Lab Report. . In the second chart provided in the Lab Report, results were summarized to the overall range and optimum pH of each organism studied. Part 3. Oxygen 1 . Using aseptic technique, each experimental organism was inoculated by introducing two drop of the culture from a sterile Pasteur pipette into the appropriate labeled tubes of molten agar. 2.
The freshly inoculated molten infusion agar was vigorously rotated between the palms of the hands to distribute the organisms. 3. Inoculated test tubes were placed in an upright position in the iced Watergate to solidify the medium rapidly. 4. The S. Erasures and A. Cecilia cultures were incubated for 24 to 48 hours at ICC and the S. Aggressive cultures for 48 to 72 hours at ICC. 1 . Each of the experimental cultures were observed for the distribution of growth in each tube. 2. Observations and determination of the oxygen requirements were recorded for each of the experimental species in the chart provided in the Lab Report.
Results: Part 1 . Observations and Results of Temperature part. Table 1. Results and observations of first part. Seriate mercenaries Pseudonymous cavitations Escherichia coli Bacillus coagulants Chromosomes aggressive Temperature Pigment Growth Gar Growth oath C (referring. ) 2+ 1+12212dd22 ICC (room temp. ) 3+ ICC (body temp. ) ICC 1+ Classification mesosphere m mesosphere Part 2. Observations and Results of pH part. Table 2. Absorbency readings Absorbency Readings Microbial Species PH pH pH pH E. Coli 0. 148 0. 476 1 . 852 1. 927 A. Fiscals 0. 83 1. 663 1. 550 1 . 750 S. Aggressive 1. 042 1 . 906 1. 714 1 . 506 Table 3. PH Summary pH Range Optimum pH 6-7 7 4. 6-9 9 6 Part 3. Oxygen requirement. Table 4. Observations and results of oxygen requirement. Species Distribution of Growth Classification According to Oxygen Requirement S. Erasures At top Obligate arroba Start at top, continues along tube Facultative anaerobe Near the top Morphological Discussion: The experimental results are presented in three parts according to the physical factor temperature, pH and oxygen requirement.
From the results in table 1 it can be noticed that all of the microorganisms investigated are anglophiles indicating that they grow at temperature range of between ICC to ICC. Also this results were expected as the anglophiles predominate in nature and this temperature range is the optimal range for cellular reactions as enzymatic activity is most efficient in this range. The enzymatic activity increases with an increase in temperature until its AD structural shape changes, as it is highly ordered molecule involving active sites that have to be ideally permanent for successful reaction.
Since, at higher temperatures the enzymes denature. The cardinal temperatures for microorganisms determined are minimal, maximal and optimal temperatures. Consequently the all microorganisms investigated appeared to be anglophiles with optimal temperature range within ICC to ICC. The Seriate mercenaries’ activity due to temperature range is provided in table 1, where it can be noticed that the pigmentation rate is maximum t ICC and decreases with increase in temperature. This species produce specific red pigment called predisposing during reproduction and as a result this molecule is responsible to the degree of pigmentation.
It was concluded that predisposing was produced at ICC and the red pigmentation appeared, but at 37 co its pigmentation rate is decreased as the pigment denatures due to relatively higher temperature. Seriate mercenaries was classified as mesosphere due to growth in temperature range between ICC to ICC. The next species of Pseudonymous cavitations and Escherichia coli show abundant Roth at ICC to ICC temperature range and were classified as anglophiles as the pigmentation degree was high and growth rate was abundant.
Bacillus coagulants and Chromosomes aggressive were also classified as mesosphere as growth was identified in temperature range of ICC to ICC, however the growth rate was relatively lower in comparison with above described species with no pigmentation appeared. The only species that shown growth at ICC are Chromosomes aggressive. Therefore the conclusion of this specie as mesosphere is questionable as it might appear as thermopile also.