The Effects of Antibiotics on Bacterial Growth
Biology II 1996
Bacteria are the most common and ancient microorganisms on earth. Most bacteria are microscopic, measuring 1 micron in length. However, colonies of bacteria grown in a laboratory petri dish can be seen with the unaided eye.
There are many divisions and classifications of bacteria that assist in identifying them. The first two types of bacteria are archaebacteria and eubacteria. Both groups have common ancestors dating to more than 3 billion years ago. Archaebacteria live in environments where, because of the high temperature, no other life can grow. These environments include hot springs and areas of volcanic activity. They contain lipids but lack certain chemicals
…show more content…
This antibiotic acts by limiting normal protein synthesis.
Streptomycin is effective against E. Coli, gram-negative bacilli, as well as many cocci.
Neomycin an antibiotic derived from a strain of Streptomyces fradiae.
Neomycin effectively destroys a wide range of bacteria.
Kanamycin an antibiotic substance derived from Streptomyces kanamycetius. Its antibacterial action is very similar to that of neomycin. Kanamycin works against many aerobic gram-positive and gram-negative bacteria, especially E. coli. Protracted use may result in auditory as well as other damages.
Erythromycin is an antibiotic produced by a strain of Streptomyces erythreaus. This antibiotic works by inhibiting protein synthesis but not nucleic synthesis. Erythromycin has inhibitory effects on gram-negative cocci as well as some gram-positive bacteria.
Chloramphenicol is a clinically useful antibiotic in combating serious infections caused by certain bacteria in place of potentially hazardous means of solving the problem. In lab tests, it has been shown that this medicine stopped bacterial reproduction in a wide range of both gram-positive and gram-negative bacteria. The inhibition of cell reproduction caused by Chloramphenicol takes place through interference with protein synthesis.
An experiment was conducted in order to determine which antibiotics are most effective in inhibiting bacterial growth. First, the different bacteria were placed on agar
The outlook on antibiotics has changed dermadicly since we have fist started using them. Antibiotics is a substance that is produced by a microorganism that can kill or prevent the growth of another microorganism. The major conflict that will be covered in the paper is antibiotic resistance. Antibiotics resistance
THE EFFECT OF INCREASING THE CONCENTRATION OF DETTOL ANTISEPTIC LIQUID ON THE GROWTH OF E.COLI
Modern-day advances have allowed scientists to develop methods to control pathogens. The more common methods include the use of antiseptics, antibiotics, and vaccines. By definition, antiseptics are chemicals used to kill pathogens. A few widespread antiseptics include soap, vinegar, and rubbing alcohol. Antiseptics are primarily used for the external destruction of pathogens, while antibiotics and vaccines target internal pathogens. Nevertheless, there are and can be difficulties concerning the use of antibiotics. “As antibiotic use has become more common, antibiotic-resistant bacteria have evolved.” This resistance due to evolution is called antibiotic resistance. It results in the antibiotics having no effect whatsoever on the bacteria, rendering the antibiotics useless. When antibiotic resistance occurs, scientists must resume their search to create a new medicine to can kill the mutant bacteria.
AIM – The aim of the experiment is to determine the relative effectiveness of several anti-microbial substances on developing pathogens. (E. coli)
Effect of 5-Fluorouracil, Penicillin G and Amphotericin on the growth of Pythium and Micrococcus luteus
The antibiotics will have different zones of inhibition on different bacteria. Also, a range of concentrations of the nutrients in the bacteria will change the bacterial growth.
Abstract-The gram-negative bacteria Serratia marcescens has gained attention in recent years for its tendency to cause nosocomial infections in humans, as well as its development of antibiotic resistance. Antibiotic resistance in a bacterium that is harmful to humans can be concerning as it can result in infections that are difficult to treat. In order to find out more about the growing antibiotic resistance of S. marcescens, this experiment used the disc diffusion method to test the susceptibility of S. marcescens to two varieties of antibiotics that were known to have success against some gram-negative bacterium: streptomycin and ampicillin. These antibiotics were, respectively, an aminoglycoside and a beta-lactam. The experiment tested which of the two that S. marcescens had developed more of a resistance to. The zones of inhibition of the discs were significantly larger for discs treated with streptomycin compared to discs treated with ampicillin. This led to the conclusion that S. marcescens is less resistant to streptomycin than to ampicillin.
Antibiotics are inarguably one of the greatest advances in medical science of the past century. Although the first natural antibiotic Penicillin was not discovered until 1928 by Scottish biologist Alexander Flemming, evidence exists that certain plant and mold growths were used to treat infections in ancient Egypt, ancient India, and classical Greece (Forrest, 1982). In our modern world with the advent of synthetic chemistry synthetic antibiotics like Erithromycin and its derivative Azithromycin have been developed. Antibiotics have many uses including the treatment of bacterial and protozoan infection, in surgical operations and prophylactically to prevent the development of an infection. Through these applications, antibiotics have saved countless lives across the world and radically altered the field of medicine. Though a wonderful and potentially lifesaving tool, antibiotic use is not without its disadvantages. Mankind has perhaps been too lax in regulation and too liberal in application of antibiotics and growing antibiotic resistance is the price we must now pay. A recent study showed that perhaps 70% of bacterial infections acquired during hospital visits in the United States are resistant to at least one class of antibiotic (Leeb, 2004). Bacteria are not helpless and their genetic capabilities have allowed them to take advantage of society’s overuse of antibiotics, allowing them to develop
The purpose of this report is to analyse the growth of the bacteria known as Citrobacter Freundii as well as distinguishing what antibiotics effect its growth. This will be done so by answering the following question after completing its associated experiments. This question includes: what antibiotics are most effective in denaturing the bacteria? It has been predicted that chloramphenicol will be the most effective due to the fact that its medical uses are treating meningitis which is an infection caused by Citrobacter freundii. After conducting the experiments it was found that the chloramphenicol antibiotic was the most effective in denaturing the bacteria, although streptomycin was also affective. However, none of the other antibiotics were able to halt the growth of the bacteria.
The aim of this investigation was to find out which antiseptics were most effective at preventing the growth of bacteria.
After gaining some knowledge about bacteria, we were giving an investigating bacteria growth lab to do. Our objective was to observe the conditions required for bacteria to grow and to test the effectiveness of substances that may be antibacterial, disinfecting, and or sanitizing. My group and I began our procedure by gathering all the bacteria by swabbing our necks and mouths. After this, we inoculated the culture by rubbing the bacteria on the agar, a nutrient rich gel made from sea kelp, on the bottom side of the container where we grow bacteria, the Petridish. We hoped for the results to come back with little or even no colonies and an immense zone of inhibition around the tiny circle cut out of filter paper covered in toothpaste, Neosporin, and Chlorhexidine Gluconate 4% Solution.
Coli. The first standard E. Coli has no resistance plasmid while the second strain contains a resistance plasmid with genes protecting it from ampicillin. This standard E. Coli and pAMP (plasmid-Ampicillin) E. Coli were each streaked across plates containing the antibiotic and containing growth supportive Lurithea Broth. The purpose of this lab was to test their growth in each medium. Our hypothesis was that while the ampicillin resistant E. Coli would show growth in both LB and LB-AMP plate, the standard E. Coli would only grow in the LB plate for it contains no resistant plasmids against the
The purpose of this experiment is to show how different concentrations of Ampicillin affect Escherichia Coli Growth and how the bacteria become resistant to the antibiotic drug. Through a series of steps, which involves streaking agar plates with E.coli sample and application of ampicillin to the E.coli sample on the agar plate, the experiment yields a result that supports the hypothesis. The hypothesis acclaims that ampicillin would affect the growth of E.coli; measuring the zone of inhibition approves the claim in the experiment. The measurements of the zone of inhibition indicate that the generation of E.coli expands as the radius reduces. The reduction of the radius shows the E.coli population is reducing and becoming resistant. In other
These mutations, no matter what process that has led to their occurrence, block the action of antibiotics by interfering with their mechanism of action (1). Currently, antibiotics attack bacteria through one of two mechanisms. In both mechanisms the antibiotic enters the microbe and interferes with production of the components needed to form new bacterial cells. Some antibiotics act on the cell membrane, causing increased permeability and leakage of cell contents. Other antibiotics interfere with protein synthesis in cells. They block one or more of the steps involved in the transformation of nucleic acids into proteins.
Examples of antibiotics that are commonly used in infection treatment include: gentamycin, tetracycline, streptomycin, and carbenicillin