You have found that the D-value (decimal reduction value) of an antimicrobial agent to be 4 minutes when the agent was exposed to a bacterial culture having an initial total viable cell count of 10° CFU/mL. After 4 minutes upon addition of the antimicrobial agent, what would have been the total viable count of the culture in this experiment? A) O 10° CFU/mL B) O 108 CFU/mL C) O 10° CFU/mL D) O 10! CFU/mL
Q: A specific heat treatment used on a particular bacterial suspension has a DRT of 10 seconds, how…
A: Heat treatments have been used for the reduction of bacterial numbers and even for sterilization…
Q: If a bacterial isolate shows intermediate to moderate resistance to an antimicrobial, how might this…
A: Bacteria are microscopic single-celled prokaryotes that thrive in diverse environmental conditions.…
Q: Design a serial dilution procedure to achieve a 56-colony count, from a sample with 8.75x105 CFU/mL…
A: Serial dilution is a progression of successive dilutions used to lessen a thick culture of cells to…
Q: Two different bacterial samples, A and B, were inoculated onto SIM media. What can you conclude…
A: SIM (Sulfide, Indole and Motility) test is done to differentiate the Gram negative bacilli based on…
Q: What is the amount (mL) of pre-culture (108 cell/mL) necessary to inoculate (to add) in a 2-liter…
A: Culture media is a solid or semisolid substance used to support the growth of microorganisms. It is…
Q: 1. Provided with the following data, compute the corresponding CFU/ml of the original culture.…
A: Various bacterial species are responsible for a variety of diseases in humans. As a result, we apply…
Q: Why is the effectiveness of an antimicrobial agent determined using an exponentially growing…
A: The bacterial cell reproduce asexually by replicating and dividing their genetic material as well as…
Q: 300 +0,005 mg/mL - 0,010 mg/mL - 0,015 mg/mL +0,020 mg/mL 0,025 mg/mL + 0,030 mg/mL -0,035 mg/mL 250…
A: Microbial Growth Curve: The number of living cells in a bacterial population over time is…
Q: From your final year project, you have isolated novel Streptococcus species that produce heat stable…
A: Nisin which is the result of Lactococcus lactis is the oldest known and most deeply analyzed and…
Q: Could an organism that is susceptible to an antimicrobial agent in laboratory testing fail to…
A: To identify the acceptable antimicrobial agent and dose for treatment of microorganism infections…
Q: How would you identify this unknown bacteria using a flowchart and the bacteria below as a possible…
A: Biochemical tests in Microbiology help in distinguishing and identifying bacteria. Through the…
Q: What is the amount (mL) of pre-culture (108 cell/mL) necessary to inoculate (to add) in a 2-liter…
A: Culture media is a solid or semisolid substance used to support the growth of microorganisms. It is…
Q: What is the differece between disinfection and sterilization? What is the dfference between…
A: Disinfection and sterilization are essential for ensuring that medical and surgical instruments do…
Q: The following data were obtained by incubating gram-positive bacteria in nutrient medium +…
A: Gram-positive bacteria are bacteria that test positive in the Gram stain test, which has…
Q: What would happen if an ampicillin reagent is added to an Lysogeny broth agar plate that is below 50…
A: Ampicillin is an antibiotic which enables the synthesis of the peptidoglycan of bacterial cells wall…
Q: Design an experiment to determine whether an antimicrobial agent is acting as a cidal or static…
A: A cidal agent means that it causes death of an organism. A static agent does not directly kill the…
Q: Is the Peptone Iron Agar (PIA) a complex or defined medium? Explain based on its composition. Is the…
A: Depending on their composition, media can be classified as defined and undefined media. Defined…
Q: When is sterilization by filtration preferred over sterilization by heat? Why? What makes heat an…
A: Answer :- 1)Filteration is the sterilization process wherein there is the physical removal of…
Q: Besides dehydrated foods, how might the amount of water available to microbes be decreased? Group of…
A: Dehydration is a method that has been used for centuries to preserve foods such as raisins, etc. It…
Q: The Kirby -Bauer antimicrobial sensitivity testing method relies on: A. The inhibition of one…
A: In Kirby -Bauer antimicrobial sensitivity testing method zone of inhibition is measured to…
Q: among these five areas such as: air, faucet, doorknow, table, and floor, in the laboratory is…
A: Microorganisms are present everywhere in nature, they are ubiquitous in their dwelling nature ie…
Q: Why do we use the term CFU (colony forming unit) instead of reporting bacteria per ml? Explain.
A: The bacterial species are responsible for causing several diseases within the human body. So, for…
Q: Is the autoclaving process absolute in killing all microorganisms? If not, what are the factors that…
A: Autoclave is an instrument or device which is used in method of moist heat sterilisation; while…
Q: Which of the following antibiotics exhibit the greatest antibacterial efficacy in the Kirby-Bauer…
A: According to Bartleby guidelines, we are supposed to attempt first question in case of multiple…
Q: Why are most antimicrobial chemical agents disinfectants rather than sterilants? What general…
A: Most chemical antimicrobial agents are disinfectants instead of sterilants. A disinfectant reduces…
Q: One of the following matches indicatIng early microbial spoilage of pharmaceutical products is…
A: Microorganisms are tiny unicellular organisms that cannot be observed by unaided eyes. They may be…
Q: A disk-diffusion test using E. coli gave the following results: Disinfectant Zone of…
A: Microbiological labs and hospitals all over the world utilise the disc diffusion test to detect the…
Q: Suppose you do the Kirby-Bauer test on a hypothetical Staphylococcus species with penicillin and…
A: "Antibiotics" are a type of antimicrobial medicine that is used to treat and prevent bacterial…
Q: If a component is heat sensitive, how might you conveniently achieve sterility of that medium? a.…
A: Option A i.e. filtration
Q: Given the scenario, compute for the total volume of the culture media solution (milliliter or liter)…
A: We have been given the concentration of the nutrient broth and Agar and we have also been given the…
Q: In theory, if a 1-liter culture of rich medium is inoculated with 3 bacterial cells per milliliter,…
A: Generation time is the time taken for the doubling of the single cell. According to data given in…
Q: Can simply observing the colonies formed on agar plates and the results of a few biochemical tests…
A: Bacteria from colonies in the agar plates and different bacterial colonies will differ in shape,…
Q: If you have 4 compounds and you test them for antimicrobial activity using a disk diffusion assay…
A: The disk diffusion assay is a culture based microbiology assay to determine the susceptibility of…
Q: operties of the Snyder deep media allow us to detect susceptibility to dental caries?
A: Dental caries (tooth decay) is injury to enamel of tooth that be converted into little holes or…
Q: Define the following terms; Sterilization, and Aseptic Technique. What are the differences between…
A: Microbes invading and proliferating within an organism's body causes infection. Microbes include…
Q: You aseptically transfer 1ml of your original liquid culture into 999 ml of sterile water. What is…
A: The dilution factor may be expressed as the ratio of the concentration of stock solution to the…
Q: Does the antibiotic disk producing the largest zone of inhibition on a plate always correspond to…
A: ZONE OF INHIBITION: The Antibiotic disk contains some Antibiotic that slowly gets dispersed in to…
Q: In which growth phase are microorganisms most sensitive to antimicrobial agents? Why?
A: Bacterial growth means that bacteria divides and result in the formation of daughter cells. There…
Q: What are the tests to determine the level of antimicrobial activity of a antimicrobial agent? How…
A: Antibiotic disc diffusion study is also known as the Kirby-Bauer method in which the susceptibility…
Q: Name at least one reason that we might want to use a Winogradsky column rather than a laboratory…
A: The Winogradsky column can be used to study various levels of growth that is aerobic or anaerobic…
Q: In the conduct of serial dilution, which of the following tools is NOT necessary? a. Agar…
A:
Q: Neutralization of residual disinfectant could be made by: a. Dilution if the concentration…
A: Disinfectants are chemical compounds that are used to destroy harmful microorganisms on non-living…
Q: What are some characteristics of microbes and infectious agents that would require handling in a…
A: Since you have asked multiple question, we will solve the first question for you. If you want any…
Q: Clear tubes in the MIC test were inoculated in Mueller-Hinton Agar to determine the MBC of the…
A: MBC - stands for minimum bactericidal concentration It is the lowest concentration of antibiotics…
Q: SEPARATION OF COMPONENTS BY CENTRIFUGATION Consider the following subcellular components and their…
A: RPM and centrifugal force: RMP is simply the rotation speed of any centrifuge machine, higher the…
Q: How can you use Alamar Blue (Resazurin) to test whether the antimicrobial compound is bactericidal…
A: Visual methods of quality and quantity are readily found in biology and other field alike as they…
Q: Why should agar media be completely dissolved before they are dispensed in tubes and plates? What…
A: Introduction A growth medium, also known as a culture medium, is a solid, liquid, or semi-solid…
Q: What is the hazard of the splattering tendency in flame sterilizing an inoculating loop? Can…
A: Aseptic preparation of culture media :-
In sterilization techniques, D-value or decimal-reduction value refers to the time taken, under specified conditions, to get one decimal logarithm reduction in the initial bacterial population. It means the time taken to kill 90% of viable microorganisms.
Step by step
Solved in 3 steps
- Is the autoclaving process absolute in killing all microorganisms? If not, what are the factors that hinder effective sterilization through autoclaving? When can you say that the sterility of an instrument is compromise?What is the relationship between dilution factors and the efficacy of antimicrobial agents in inhibiting bacterial growth?What is the amount (mL) of pre-culture (108 cell/mL) necessary to inoculate (to add) in a 2-liter culture media for a concentration of 6.5 × 106 cells/mL?
- Assume that you are adding 300 microliters of 1% substrate solution per well in a 24-well plate. If we can order 5 milligrams of fibronectin for $871.00, how much would it cost to have enough to use every well of the 24-well culture plate?A specific heat treatment used on a particular bacterial suspension has a DRT of 10 seconds, how much time would be required to achieve a 5 log reduction in numbers of bacteria?In aseptic technique, what will happen if the inoculated solid plated media is not inverted prior to incubation?
- Of what practical importance are air borne microorganisms to the laboratory workers? What precautions should be taken to control laboratory contaminants? What precautions should be taken to control laboratory contaminants? Of what advantage is the using a solid and a liquid medium?Why does a precipitate form on Sierra’s medium when inoculated with a lipolytic organism? Discuss the principle behind this procedure.If cultures are suffering severely due to alkaloid production and accumulation in the medium then, how can i overcome this problem?
- Consider the sterilization of a sodium gluconate production medium in the holding section of a continuous sterilizer. Assuming constant temperature, the specific death rate constant of the contaminant is 20 s-1 . If the average residence time in the holding section is 10 seconds, calculate the Del factor for the following and explain the results. i. For Pe = 400 ii. For Pe = 400, assuming plug flow iii. For Pe = 100 iv. For Pe = 100, assuming plug flowWhy is CFU more applicable to a culture of Streptococcus than to a culture of E. coli?What are some characteristics of microbes and infectious agents that would require handling in a BSL-3 laboratory? What is the purpose of degerming? Does it completely eliminate microbes? What are some factors that alter the effectiveness of a disinfectant? When plotting microbial death curves, how might they look different for bactericidal versus bacteriostatic treatments? What are the benefits of cleaning something to a level of cleanliness beyond what is required? What are some possible disadvantages of doing so?