Chemical methods: antimicrobial agents

Question 1

Antimicrobial agents can be

classified as

Answer 1

• Bacteriostatic
• Bacteriocidal
• Bacteriolytic

Question 2

Bacteriostatic is?

Answer 2

inhibit growth of microorganism

Question 3

Bacteriocidal is ?

Answer 3

kill microorganism

Question 4

Bacteriolytic?

Answer 4

kill microorganim by inducing lysis

Question 5

What’s the difference between total cell counto and viable cell count?

Answer 5

total c dead+alive

viable: only the alive

Question 6

Minimum inhibitory concentration (MIC)

Answer 6

smallest amount of an agent
needed to inhibit growth of a
microorganism

Question 7

Minimum lethal concentration (MLC)

Answer 7

the lowest concentration of an agent

that kills a test organism

Question 8

Minimum bacteriocidal concentration

MBC

Answer 8

the lowest concentration of

an agent that kills a test bacterium

Question 9

MIC varies with?

Answer 9

the organism used, inoculum size, temp and PH

Question 10

in bacteriostatic the total cell count and viable cell count is going to ?

Answer 10

plateau

Question 11

in bacteriocidal, the total cell count and the viable cell count is going to ?

Answer 11

the total va pas changer mais le viable va decrease as the microorganism are killed

Question 12

in bacteriolytic

Answer 12

both decreasing cause them to lyse so they all decrease

Question 13

to determine the mbc?

Answer 13

take sample of the last 3 tubes and make a sample on agar

Question 14

the tube with absolutely no growth is ?

Answer 14

the MBC

Question 15

dics diffusion assay?

Answer 15

Antimicrobial agent added to

filter paper disc.

Question 16

in a disc diffusion assay the MIC is?

Answer 16

reached at some distance from the disc

Question 17

what’s the zone of inhibition?

Answer 17

area of no growth around the disc

Question 18

bigger the zone of clear?

Answer 18

more the microbe is sensible to the antibiotic

Question 19

Antimicrobial compounds are used to

Answer 19

-prevent spreading of a pathogen in the
environment,
-prevent contamination of the host
-cure superficial bacterial
infections

Question 20

Sterilants:

Answer 20

destroy all forms of microorganisms, including endospores

Question 21

These antimicrobial agents can be divided into two categories

Answer 21

• products use to control microorganisms in commercial-industrial applications
• other designed to prevent growth of human pathogens in inanimate environment and on external body surfaces

Question 22

Disinfectants/Sanitizers:

Answer 22

applied to nonliving objects or surface (can be toxic for

animals/humans)

Question 23

Disinfectants/Sanitizers do not kill?

Answer 23

endospores

Question 24

Antiseptics?

Answer 24

applied to the surface of living tissues or skin (must not be toxic for
animals/humans)

Question 25

antiseptics do not?

Answer 25

kill endospores

Question 26

Antimicrobial drugs:

Answer 26

drugs: Antibiotics, antifungals, antivirals: applied outside or inside the body of animals/humans (must not be toxic for animals/humans).

Question 27

Antimicrobial drug do not ?

Answer 27

kill endospores

Question 28

Examples of Antiseptics, Desinfectants, | Sterilants

Answer 28

- Phenol-phenolics - Alcohols - Halogens - Heavy metals - Quaternary ammonium - Alkylatin agents

Question 29

Phenol/phenolics are used as?

Answer 29

desinfectant(D) and antiseptic(A)

Question 30

what does phenol do?

Answer 30

disrupt cytoplasmic membrane,protein denaturant

Question 31

Alcohols are used as?

Answer 31

D,A

Question 32

what does alcohols do?

Answer 32

- lipid solvent | - protein denaturants

Question 33

100 or 70 who works better than ?

Answer 33

70 because dehydrated them

Question 34

Halogens are used as?

Answer 34

D,A,S(sterilant)

Question 35

exemple of halogens?

Answer 35

- chlorine(S,D) | - iodine(A)

Question 36

chlorines job is an?

Answer 36

oxidizing agent(ex sodium hypochlorite)

Question 37

iodine(A) is and?

Answer 37

iodinate tyrosine residues in protein,oxidizing agent

Question 38

Heavy metals are used as?

Answer 38

Desinfectant

Question 39

heavy metals job?

Answer 39

-modify proteins -interact with RNA,DNA in different ways (CuSO4,algaecide)

Question 40

Quaternary | ammonium act as?

Answer 40

desinfectant and antiseptic

Question 41

Quaternary | ammonium what's their job?

Answer 41

Interact with phospholipids of cytoplasmic membrane

Question 42

Alkylating agents what's their job?

Answer 42

very toxic

Question 43

exemple of alkylating agents?

Answer 43

formaldehyde and glutaraldehyde