1Baird-Parker Agar (BPA)his is a selective medium for the isolation of Staphylococcus species. It has lithium chloride and glycine to inhibit the growth of Gram-negative bacteria and most Gram-positive bacteria except Staphylococcus. Egg yolk emulsion is added to detect lecithinase production and tellurite reduction. S. aureus colonies on BPA are black due to reduction of tellurite, and they exhibit a clear zone due to lecithinase activity on egg yolk.
2Mannitol Salt Agar (MSA), or Chapman AgarThis is a selective and differential medium. The high concentration of NaCl (~7.5%) selects for halophiles, organisms that can tolerate high salt concentrations, thereby favouring the growth of Staphylococcus species. Mannitol is the differential component: S. aureus ferments mannitol, lowering the pH of the medium, which results in a color change of the pH indicator from red to yellow. Thus, growth of S. aureus is indicated by yellow colonies.
3Blood Agar (BA)This is a nutrient-rich, differential medium that supports the growth of many organisms. S. aureus forms colonies that are round, smooth, and golden-yellow. This bacterium typically demonstrates β-hemolysis, which is complete lysis of red blood cells, resulting in a clear zone around the colonies. This hemolysis is due to the production of hemolysins by S. aureus.
4Sauton’s MediumA liquid medium that lacks detergents, which helps in the formation of corded colonies. When M. tuberculosis grows in this medium, it results in turbidity.
5Sula’s MediumA liquid medium containing glycerol, asparagine, and a variety of salts. The growth of M. tuberculosis results in turbidity.
6Middlebrook 7H9 BrothThis is a liquid medium that contains glycerol and Tween 80, which prevent clumping of mycobacteria. The growth of M. tuberculosis results in turbidity.
7Dubos’ MediumA liquid medium that contains a mixture of salts, fatty acids, and polysorbate. When M. tuberculosis grows in this medium, it causes the medium to become turbid.
8Dorset MediumAn egg-based medium. M. tuberculosis colonies appear similar to those on Petragnini Medium: small, round, buff-colored, and taking 3-4 weeks to develop.
9Middlebrook 7H11 AgarThis is a nutrient-rich medium similar to 7H10 but includes additional pyruvate for energy source, promoting more luxurious growth. The colonies of M. tuberculosis appear small, slightly domed, and rough with a butyrous consistency.
10Middlebrook 7H10 AgarA selective medium that contains oleic acid, albumin, dextrose, and catalase. The colonies of M. tuberculosis appear small, rough, and buff to white-colored, taking less time to appear compared to egg-based media.
11Petragnini MediumAn egg-based medium enriched with additional nutrients to promote the growth of Mycobacterium tuberculosis. Colonies of M. tuberculosis are small, round, buff-colored, and typically take 3-4 weeks to appear.
12Lowenstein-Jensen (LJ) MediumAn egg-based medium that uses malachite green to suppress the growth of other bacteria and glycerol to stimulate the growth of Mycobacterium tuberculosis. The colonies of M. tuberculosis on LJ are non-pigmented, dry, rough, raised, irregular with a wrinkled surface, initially creamy-white, turning yellowish or buff-colored on further incubation.
13Liquid Media (such as Nutrient Broth)E. coli exhibits homogenous turbid growth within 12-18 hours. After prolonged incubation, pellicles may form on the surface of the media.
14Sorbitol-MacConkey agarA variant of MacConkey agar, used in detecting E. coli O157:H7, which does not ferment sorbitol, unlike most strains of E. coli.
15Triple Sugar Iron (TSI) AgarE. coli typically produces an acid butt, acid slant, and gas, with no H2S production, indicating it ferments lactose, sucrose, and glucose.
16Tryptic Soy Agar (TSA)A general purpose medium. E. coli colonies are medium to large, with a shiny moist appearance.
17Cystine Lactose Electrolyte-Deficient (CLED) AgarE. coli will give lactose-positive yellow colonies.
18Violet Red Bile Agar (VRBA)E. coli colonies are red (pink to red) and may show bluish fluorescence under UV light.
19Nutrient Agar (NA)A non-selective medium. E. coli colonies are usually large, circular, grayish-white, moist, and smooth.
20Cornmeal Agar with Tween 80It is used for the identification of Candida species by promoting the formation of chlamydospores, which is a characteristic of Candida albicans.
21RPMI 1640 MediumIt is a rich medium that contains inorganic salts, glucose, amino acids, vitamins, and other nutrients that promote the growth of yeast cells.
22Blood AgarA differential medium used to identify bacteria based on their hemolytic properties. E. faecalis typically shows gamma-hemolysis on this medium, i.e., no hemolysis or change in the color of the medium.
23MacConkey AgarTraditionally used to isolate and differentiate Gram-negative bacilli, E. faecalis can grow on this medium, producing small, round, magenta pink colonies due to lactose fermentation, indicating a positive result.
24Azide Dextrose BrothA selective medium inhibiting Gram-negative bacteria, used for the isolation of streptococci and staphylococci from mixed samples. E. faecalis will show a positive growth resulting in a turbid appearance of the broth.
25Brain-Heart Infusion (BHI) Broth or AgarThis is a nutrient-rich medium that supports the growth of a variety of fastidious organisms, including E. faecalis. The typical phenotype of E. faecalis on BHI is small, round, and white colonies.
26Tryptic Soy Broth or Agar (TSB/TSA)A general-purpose medium that supports the growth of a broad spectrum of bacteria. E. faecalis on TSA will typically form small, round, and white colonies, indicating a positive growth.
1Sf1Ep mediumCulturing Treponema pallidum, the bacteria that causes syphilis, in vitro is a challenge. T. pallidum is not routinely cultured in the laboratory for diagnostic purposes, in part because it cannot be grown on artificial media. However, a breakthrough in culturing T. pallidum was reported in 2018 when researchers managed to grow the bacterium in a rabbit epithelial cell line (Sf1Ep) using a medium called 'Sf1Ep medium'. It's not used for routine diagnostic purposes, but for research only. The diagnosis involves direct microscopic examination, serologic tests, molecular tests and histopathology.
2Phenol Red Mannitol BrothThis is a differential medium, used to determine an organism's ability to ferment mannitol. S. aureus, which can ferment mannitol, will change the medium from red to yellow due to acid production.
3DNase Test AgarS. aureus produces the enzyme DNase which hydrolyses DNA. When S. aureus grows on this medium, the DNA is broken down, which can be visualised using a hydrochloric acid (HCl) solution: clear zones around the colonies indicate DNA breakdown.
4Mannitol Salt Agar (MSA), or Chapman AgarThis is a selective and differential medium. The high concentration of NaCl (~7.5%) selects for halophiles, organisms that can tolerate high salt concentrations, thereby favouring the growth of Staphylococcus species. Mannitol is the differential component: S. aureus ferments mannitol, lowering the pH of the medium, which results in a color change of the pH indicator from red to yellow. Thus, growth of S. aureus is indicated by yellow colonies.
5Blood Agar (BA)This is a nutrient-rich, differential medium that supports the growth of many organisms. S. aureus forms colonies that are round, smooth, and golden-yellow. This bacterium typically demonstrates β-hemolysis, which is complete lysis of red blood cells, resulting in a clear zone around the colonies. This hemolysis is due to the production of hemolysins by S. aureus.
6Sauton’s MediumA liquid medium that lacks detergents, which helps in the formation of corded colonies. When M. tuberculosis grows in this medium, it results in turbidity.
7BACTECThis is not a traditional medium but a system for detecting the growth of M. tuberculosis by monitoring the release of C14O2 from C14 palmitic acid, which the bacteria metabolize. An increase in radioactive counts in the BACTEC instrument indicates the growth of bacteria.
8Sula’s MediumA liquid medium containing glycerol, asparagine, and a variety of salts. The growth of M. tuberculosis results in turbidity.
9Proskauer and Beck’s MediumA liquid medium. The growth of M. tuberculosis causes turbidity.
10Dubos’ MediumA liquid medium that contains a mixture of salts, fatty acids, and polysorbate. When M. tuberculosis grows in this medium, it causes the medium to become turbid.
11Pawlowsky MediumA potato-based medium. Growth of M. tuberculosis may be similar to that seen on the LJ Medium.
12Loeffler MediumA serum-based medium. M. tuberculosis colonies on Loeffler medium are small, dry, wrinkled, and off-white to yellow.
13Dorset MediumAn egg-based medium. M. tuberculosis colonies appear similar to those on Petragnini Medium: small, round, buff-colored, and taking 3-4 weeks to develop.
14Petragnini MediumAn egg-based medium enriched with additional nutrients to promote the growth of Mycobacterium tuberculosis. Colonies of M. tuberculosis are small, round, buff-colored, and typically take 3-4 weeks to appear.
15Lowenstein-Jensen (LJ) MediumAn egg-based medium that uses malachite green to suppress the growth of other bacteria and glycerol to stimulate the growth of Mycobacterium tuberculosis. The colonies of M. tuberculosis on LJ are non-pigmented, dry, rough, raised, irregular with a wrinkled surface, initially creamy-white, turning yellowish or buff-colored on further incubation.
16Lysine Iron Agar (LIA)Used to determine the ability of an organism to decarboxylate or deaminate lysine and to form hydrogen sulfide. E. coli is typically lysine decarboxylase positive and H2S negative, so you would see a reaction of red/purple slant and purple/red butt with no black precipitate.
17Sorbitol-MacConkey agarA variant of MacConkey agar, used in detecting E. coli O157:H7, which does not ferment sorbitol, unlike most strains of E. coli.
18Urea Agar/BrothE. coli is typically urease negative, so no color change would be expected in this medium.
19Triple Sugar Iron (TSI) AgarE. coli typically produces an acid butt, acid slant, and gas, with no H2S production, indicating it ferments lactose, sucrose, and glucose.
20Simmons Citrate AgarUsed for citrate utilization testing. E. coli usually can't utilize citrate as a sole carbon source, so no growth or color change would be expected.
21m-ENDO AgarE. coli colonies appear as green with a metallic sheen, indicating lactose fermentation.
22Eosin Methylene Blue (EMB) AgarA selective and differential medium where E. coli forms distinctive metallic green sheen colonies due to vigorous lactose fermentation.
23Mueller Hinton Agar (MHA)Typically used for antibiotic susceptibility testing. E. coli colonies appear pale straw colored.
24MacConkey Agar (MAC)This selective and differential medium distinguishes lactose fermenters from non-fermenters. E. coli colonies are circular, moist, smooth, and pink.
25Blood Agar (BA)E. coli colonies on this differential medium are large, circular, gray, moist, and can show β-hemolysis.
26Nutrient Agar (NA)A non-selective medium. E. coli colonies are usually large, circular, grayish-white, moist, and smooth.
27Nickerson’s Medium or Bismuth Sulfite Glucose Glycine Yeast (BSGG)This medium is used to stimulate the production of germ tubes, a characteristic of Candida albicans.
28Cornmeal Agar with Tween 80It is used for the identification of Candida species by promoting the formation of chlamydospores, which is a characteristic of Candida albicans.
29CHROMagar CandidaThis differential medium allows for the isolation and identification of Candida species based on colony color. Candida albicans usually forms green colonies on this medium.
30Potato Dextrose Agar (PDA)Potato Dextrose Agar (PDA) consists of a nutrient-rich substrate, made from dehydrated Potato Infusion and Dextrose, ideal for robust mycological propagation. Agar provides the solidifying medium. Acidification, typically using sterile tartaric acid, adjusts the pH to 3.5 +/- 0.1 to create a more selective environment by inhibiting bacterial proliferation. Additionally, Chloramphenicol is incorporated as an antimicrobial agent to further suppress bacterial contamination, thereby facilitating the selective isolation of fungi.
31Sabouraud Dextrose Agar (SDA)It is composed of peptone, dextrose (glucose), and agar. The high dextrose concentration promotes fungal growth, while the acidic pH inhibits bacterial growth.
32Nutrient AgarIt is a general-purpose medium. However, E. faecalis grows poorly on nutrient agar, which means it does not proliferate as well on this medium compared to the others listed, indicating a negative or poor growth.
33Blood AgarA differential medium used to identify bacteria based on their hemolytic properties. E. faecalis typically shows gamma-hemolysis on this medium, i.e., no hemolysis or change in the color of the medium.
34MacConkey AgarTraditionally used to isolate and differentiate Gram-negative bacilli, E. faecalis can grow on this medium, producing small, round, magenta pink colonies due to lactose fermentation, indicating a positive result.
35Azide Dextrose BrothA selective medium inhibiting Gram-negative bacteria, used for the isolation of streptococci and staphylococci from mixed samples. E. faecalis will show a positive growth resulting in a turbid appearance of the broth.
36Enterococcosel AgarA selective and differential medium that inhibits the growth of Gram-negative bacteria and distinguishes enterococci based on their ability to grow in the presence of bile and hydrolyze esculin. E. faecalis will form small, black colonies on this medium due to esculin hydrolysis.
37Tryptic Soy Broth or Agar (TSB/TSA)A general-purpose medium that supports the growth of a broad spectrum of bacteria. E. faecalis on TSA will typically form small, round, and white colonies, indicating a positive growth.
1Phenol Red Mannitol BrothThis is a differential medium, used to determine an organism's ability to ferment mannitol. S. aureus, which can ferment mannitol, will change the medium from red to yellow due to acid production.
2DNase Test AgarS. aureus produces the enzyme DNase which hydrolyses DNA. When S. aureus grows on this medium, the DNA is broken down, which can be visualised using a hydrochloric acid (HCl) solution: clear zones around the colonies indicate DNA breakdown.
3Sauton’s MediumA liquid medium that lacks detergents, which helps in the formation of corded colonies. When M. tuberculosis grows in this medium, it results in turbidity.
4Middlebrook 7H9 BrothThis is a liquid medium that contains glycerol and Tween 80, which prevent clumping of mycobacteria. The growth of M. tuberculosis results in turbidity.
5Dubos’ MediumA liquid medium that contains a mixture of salts, fatty acids, and polysorbate. When M. tuberculosis grows in this medium, it causes the medium to become turbid.
6Pawlowsky MediumA potato-based medium. Growth of M. tuberculosis may be similar to that seen on the LJ Medium.
7Loeffler MediumA serum-based medium. M. tuberculosis colonies on Loeffler medium are small, dry, wrinkled, and off-white to yellow.
8Tarshis MediumA blood-based medium that can promote the growth of M. tuberculosis. The colonies appear similar to those on the LJ Medium.
9Middlebrook 7H10 AgarA selective medium that contains oleic acid, albumin, dextrose, and catalase. The colonies of M. tuberculosis appear small, rough, and buff to white-colored, taking less time to appear compared to egg-based media.
10Petragnini MediumAn egg-based medium enriched with additional nutrients to promote the growth of Mycobacterium tuberculosis. Colonies of M. tuberculosis are small, round, buff-colored, and typically take 3-4 weeks to appear.
11Lowenstein-Jensen (LJ) MediumAn egg-based medium that uses malachite green to suppress the growth of other bacteria and glycerol to stimulate the growth of Mycobacterium tuberculosis. The colonies of M. tuberculosis on LJ are non-pigmented, dry, rough, raised, irregular with a wrinkled surface, initially creamy-white, turning yellowish or buff-colored on further incubation.
12Lysine Iron Agar (LIA)Used to determine the ability of an organism to decarboxylate or deaminate lysine and to form hydrogen sulfide. E. coli is typically lysine decarboxylase positive and H2S negative, so you would see a reaction of red/purple slant and purple/red butt with no black precipitate.
13Brilliant Green Agar (BGA)A selective medium that is used to isolate Salmonella species, but E. coli can grow on it, albeit not as well.
14Triple Sugar Iron (TSI) AgarE. coli typically produces an acid butt, acid slant, and gas, with no H2S production, indicating it ferments lactose, sucrose, and glucose.
15Simmons Citrate AgarUsed for citrate utilization testing. E. coli usually can't utilize citrate as a sole carbon source, so no growth or color change would be expected.
16Cystine Lactose Electrolyte-Deficient (CLED) AgarE. coli will give lactose-positive yellow colonies.
17Mueller Hinton Agar (MHA)Typically used for antibiotic susceptibility testing. E. coli colonies appear pale straw colored.
18MacConkey Agar (MAC)This selective and differential medium distinguishes lactose fermenters from non-fermenters. E. coli colonies are circular, moist, smooth, and pink.
19Cornmeal Agar with Tween 80It is used for the identification of Candida species by promoting the formation of chlamydospores, which is a characteristic of Candida albicans.
20RPMI 1640 MediumIt is a rich medium that contains inorganic salts, glucose, amino acids, vitamins, and other nutrients that promote the growth of yeast cells.
21Blood AgarA differential medium used to identify bacteria based on their hemolytic properties. E. faecalis typically shows gamma-hemolysis on this medium, i.e., no hemolysis or change in the color of the medium.
22Azide Dextrose BrothA selective medium inhibiting Gram-negative bacteria, used for the isolation of streptococci and staphylococci from mixed samples. E. faecalis will show a positive growth resulting in a turbid appearance of the broth.
23Todd-Hewitt BrothA liquid enrichment medium used for the cultivation of fastidious organisms such as streptococci and enterococci. E. faecalis will lead to a turbid broth due to microbial growth.
24Enterococcosel AgarA selective and differential medium that inhibits the growth of Gram-negative bacteria and distinguishes enterococci based on their ability to grow in the presence of bile and hydrolyze esculin. E. faecalis will form small, black colonies on this medium due to esculin hydrolysis.
25Tryptic Soy Broth or Agar (TSB/TSA)A general-purpose medium that supports the growth of a broad spectrum of bacteria. E. faecalis on TSA will typically form small, round, and white colonies, indicating a positive growth.
1Sf1Ep mediumCulturing Treponema pallidum, the bacteria that causes syphilis, in vitro is a challenge. T. pallidum is not routinely cultured in the laboratory for diagnostic purposes, in part because it cannot be grown on artificial media. However, a breakthrough in culturing T. pallidum was reported in 2018 when researchers managed to grow the bacterium in a rabbit epithelial cell line (Sf1Ep) using a medium called 'Sf1Ep medium'. It's not used for routine diagnostic purposes, but for research only. The diagnosis involves direct microscopic examination, serologic tests, molecular tests and histopathology.
2Mannitol Salt Agar (MSA), or Chapman AgarThis is a selective and differential medium. The high concentration of NaCl (~7.5%) selects for halophiles, organisms that can tolerate high salt concentrations, thereby favouring the growth of Staphylococcus species. Mannitol is the differential component: S. aureus ferments mannitol, lowering the pH of the medium, which results in a color change of the pH indicator from red to yellow. Thus, growth of S. aureus is indicated by yellow colonies.
3Blood Agar (BA)This is a nutrient-rich, differential medium that supports the growth of many organisms. S. aureus forms colonies that are round, smooth, and golden-yellow. This bacterium typically demonstrates β-hemolysis, which is complete lysis of red blood cells, resulting in a clear zone around the colonies. This hemolysis is due to the production of hemolysins by S. aureus.
4Sauton’s MediumA liquid medium that lacks detergents, which helps in the formation of corded colonies. When M. tuberculosis grows in this medium, it results in turbidity.
5Sula’s MediumA liquid medium containing glycerol, asparagine, and a variety of salts. The growth of M. tuberculosis results in turbidity.
6Middlebrook 7H9 BrothThis is a liquid medium that contains glycerol and Tween 80, which prevent clumping of mycobacteria. The growth of M. tuberculosis results in turbidity.
7Pawlowsky MediumA potato-based medium. Growth of M. tuberculosis may be similar to that seen on the LJ Medium.
8Loeffler MediumA serum-based medium. M. tuberculosis colonies on Loeffler medium are small, dry, wrinkled, and off-white to yellow.
9Tarshis MediumA blood-based medium that can promote the growth of M. tuberculosis. The colonies appear similar to those on the LJ Medium.
10Sorbitol-MacConkey agarA variant of MacConkey agar, used in detecting E. coli O157:H7, which does not ferment sorbitol, unlike most strains of E. coli.
11Triple Sugar Iron (TSI) AgarE. coli typically produces an acid butt, acid slant, and gas, with no H2S production, indicating it ferments lactose, sucrose, and glucose.
12Simmons Citrate AgarUsed for citrate utilization testing. E. coli usually can't utilize citrate as a sole carbon source, so no growth or color change would be expected.
13Tryptic Soy Agar (TSA)A general purpose medium. E. coli colonies are medium to large, with a shiny moist appearance.
14Violet Red Bile Agar (VRBA)E. coli colonies are red (pink to red) and may show bluish fluorescence under UV light.
15Mueller Hinton Agar (MHA)Typically used for antibiotic susceptibility testing. E. coli colonies appear pale straw colored.
16Blood Agar (BA)E. coli colonies on this differential medium are large, circular, gray, moist, and can show β-hemolysis.
17Nutrient Agar (NA)A non-selective medium. E. coli colonies are usually large, circular, grayish-white, moist, and smooth.
18Nickerson’s Medium or Bismuth Sulfite Glucose Glycine Yeast (BSGG)This medium is used to stimulate the production of germ tubes, a characteristic of Candida albicans.
19Cornmeal Agar with Tween 80It is used for the identification of Candida species by promoting the formation of chlamydospores, which is a characteristic of Candida albicans.
20CHROMagar CandidaThis differential medium allows for the isolation and identification of Candida species based on colony color. Candida albicans usually forms green colonies on this medium.
21RPMI 1640 MediumIt is a rich medium that contains inorganic salts, glucose, amino acids, vitamins, and other nutrients that promote the growth of yeast cells.
22Sabouraud Dextrose Agar (SDA)It is composed of peptone, dextrose (glucose), and agar. The high dextrose concentration promotes fungal growth, while the acidic pH inhibits bacterial growth.
23Blood AgarA differential medium used to identify bacteria based on their hemolytic properties. E. faecalis typically shows gamma-hemolysis on this medium, i.e., no hemolysis or change in the color of the medium.
24Todd-Hewitt BrothA liquid enrichment medium used for the cultivation of fastidious organisms such as streptococci and enterococci. E. faecalis will lead to a turbid broth due to microbial growth.
25Bile Esculin Agar (BEA)A selective and differential medium that differentiates group D Streptococci and Enterococci based on the ability to hydrolyze esculin in the presence of bile. E. faecalis hydrolyzes esculin, leading to the formation of a dark brown or black precipita
26Brain-Heart Infusion (BHI) Broth or AgarThis is a nutrient-rich medium that supports the growth of a variety of fastidious organisms, including E. faecalis. The typical phenotype of E. faecalis on BHI is small, round, and white colonies.
1Mueller Hinton Agar (MHA)Typically used for antibiotic susceptibility testing. E. coli colonies appear pale straw colored.
2Middlebrook 7H9 BrothThis is a liquid medium that contains glycerol and Tween 80, which prevent clumping of mycobacteria. The growth of M. tuberculosis results in turbidity.
3Nutrient Agar (NA)A non-selective medium. E. coli colonies are usually large, circular, grayish-white, moist, and smooth.
4Blood Agar (BA)E. coli colonies on this differential medium are large, circular, gray, moist, and can show β-hemolysis.
5Liquid Media (such as Nutrient Broth)E. coli exhibits homogenous turbid growth within 12-18 hours. After prolonged incubation, pellicles may form on the surface of the media.
6Tryptic Soy Broth or Agar (TSB/TSA)A general-purpose medium that supports the growth of a broad spectrum of bacteria. E. faecalis on TSA will typically form small, round, and white colonies, indicating a positive growth.
7Eosin Methylene Blue (EMB) AgarA selective and differential medium where E. coli forms distinctive metallic green sheen colonies due to vigorous lactose fermentation.
8Potato Dextrose Agar (PDA)Potato Dextrose Agar (PDA) consists of a nutrient-rich substrate, made from dehydrated Potato Infusion and Dextrose, ideal for robust mycological propagation. Agar provides the solidifying medium. Acidification, typically using sterile tartaric acid, adjusts the pH to 3.5 +/- 0.1 to create a more selective environment by inhibiting bacterial proliferation. Additionally, Chloramphenicol is incorporated as an antimicrobial agent to further suppress bacterial contamination, thereby facilitating the selective isolation of fungi.
9Nutrient AgarIt is a general-purpose medium. However, E. faecalis grows poorly on nutrient agar, which means it does not proliferate as well on this medium compared to the others listed, indicating a negative or poor growth.
10Cystine Lactose Electrolyte-Deficient (CLED) AgarE. coli will give lactose-positive yellow colonies.
11Proskauer and Beck’s MediumA liquid medium. The growth of M. tuberculosis causes turbidity.
12Simmons Citrate AgarUsed for citrate utilization testing. E. coli usually can't utilize citrate as a sole carbon source, so no growth or color change would be expected.
13Blood Agar (BA)This is a nutrient-rich, differential medium that supports the growth of many organisms. S. aureus forms colonies that are round, smooth, and golden-yellow. This bacterium typically demonstrates β-hemolysis, which is complete lysis of red blood cells, resulting in a clear zone around the colonies. This hemolysis is due to the production of hemolysins by S. aureus.
14Pawlowsky MediumA potato-based medium. Growth of M. tuberculosis may be similar to that seen on the LJ Medium.
15Loeffler MediumA serum-based medium. M. tuberculosis colonies on Loeffler medium are small, dry, wrinkled, and off-white to yellow.
16Sauton’s MediumA liquid medium that lacks detergents, which helps in the formation of corded colonies. When M. tuberculosis grows in this medium, it results in turbidity.
17MacConkey Agar (MAC)This selective and differential medium distinguishes lactose fermenters from non-fermenters. E. coli colonies are circular, moist, smooth, and pink.
18Azide Dextrose BrothA selective medium inhibiting Gram-negative bacteria, used for the isolation of streptococci and staphylococci from mixed samples. E. faecalis will show a positive growth resulting in a turbid appearance of the broth.
19Middlebrook 7H11 AgarThis is a nutrient-rich medium similar to 7H10 but includes additional pyruvate for energy source, promoting more luxurious growth. The colonies of M. tuberculosis appear small, slightly domed, and rough with a butyrous consistency.
20Bile Esculin Agar (BEA)A selective and differential medium that differentiates group D Streptococci and Enterococci based on the ability to hydrolyze esculin in the presence of bile. E. faecalis hydrolyzes esculin, leading to the formation of a dark brown or black precipita
21Sf1Ep mediumCulturing Treponema pallidum, the bacteria that causes syphilis, in vitro is a challenge. T. pallidum is not routinely cultured in the laboratory for diagnostic purposes, in part because it cannot be grown on artificial media. However, a breakthrough in culturing T. pallidum was reported in 2018 when researchers managed to grow the bacterium in a rabbit epithelial cell line (Sf1Ep) using a medium called 'Sf1Ep medium'. It's not used for routine diagnostic purposes, but for research only. The diagnosis involves direct microscopic examination, serologic tests, molecular tests and histopathology.
22Blood AgarA differential medium used to identify bacteria based on their hemolytic properties. E. faecalis typically shows gamma-hemolysis on this medium, i.e., no hemolysis or change in the color of the medium.
23Dubos’ MediumA liquid medium that contains a mixture of salts, fatty acids, and polysorbate. When M. tuberculosis grows in this medium, it causes the medium to become turbid.
24Tarshis MediumA blood-based medium that can promote the growth of M. tuberculosis. The colonies appear similar to those on the LJ Medium.
25Lysine Iron Agar (LIA)Used to determine the ability of an organism to decarboxylate or deaminate lysine and to form hydrogen sulfide. E. coli is typically lysine decarboxylase positive and H2S negative, so you would see a reaction of red/purple slant and purple/red butt with no black precipitate.
26MacConkey AgarTraditionally used to isolate and differentiate Gram-negative bacilli, E. faecalis can grow on this medium, producing small, round, magenta pink colonies due to lactose fermentation, indicating a positive result.
27Sabouraud Dextrose Agar (SDA)It is composed of peptone, dextrose (glucose), and agar. The high dextrose concentration promotes fungal growth, while the acidic pH inhibits bacterial growth.
28Sorbitol-MacConkey agarA variant of MacConkey agar, used in detecting E. coli O157:H7, which does not ferment sorbitol, unlike most strains of E. coli.
29Petragnini MediumAn egg-based medium enriched with additional nutrients to promote the growth of Mycobacterium tuberculosis. Colonies of M. tuberculosis are small, round, buff-colored, and typically take 3-4 weeks to appear.
30Enterococcosel AgarA selective and differential medium that inhibits the growth of Gram-negative bacteria and distinguishes enterococci based on their ability to grow in the presence of bile and hydrolyze esculin. E. faecalis will form small, black colonies on this medium due to esculin hydrolysis.
31Phenol Red Mannitol BrothThis is a differential medium, used to determine an organism's ability to ferment mannitol. S. aureus, which can ferment mannitol, will change the medium from red to yellow due to acid production.
32Todd-Hewitt BrothA liquid enrichment medium used for the cultivation of fastidious organisms such as streptococci and enterococci. E. faecalis will lead to a turbid broth due to microbial growth.
33Nickerson’s Medium or Bismuth Sulfite Glucose Glycine Yeast (BSGG)This medium is used to stimulate the production of germ tubes, a characteristic of Candida albicans.
34Cornmeal Agar with Tween 80It is used for the identification of Candida species by promoting the formation of chlamydospores, which is a characteristic of Candida albicans.
35Triple Sugar Iron (TSI) AgarE. coli typically produces an acid butt, acid slant, and gas, with no H2S production, indicating it ferments lactose, sucrose, and glucose.
36Sula’s MediumA liquid medium containing glycerol, asparagine, and a variety of salts. The growth of M. tuberculosis results in turbidity.
37Urea Agar/BrothE. coli is typically urease negative, so no color change would be expected in this medium.
38Middlebrook 7H10 AgarA selective medium that contains oleic acid, albumin, dextrose, and catalase. The colonies of M. tuberculosis appear small, rough, and buff to white-colored, taking less time to appear compared to egg-based media.
39Lowenstein-Jensen (LJ) MediumAn egg-based medium that uses malachite green to suppress the growth of other bacteria and glycerol to stimulate the growth of Mycobacterium tuberculosis. The colonies of M. tuberculosis on LJ are non-pigmented, dry, rough, raised, irregular with a wrinkled surface, initially creamy-white, turning yellowish or buff-colored on further incubation.
40Baird-Parker Agar (BPA)his is a selective medium for the isolation of Staphylococcus species. It has lithium chloride and glycine to inhibit the growth of Gram-negative bacteria and most Gram-positive bacteria except Staphylococcus. Egg yolk emulsion is added to detect lecithinase production and tellurite reduction. S. aureus colonies on BPA are black due to reduction of tellurite, and they exhibit a clear zone due to lecithinase activity on egg yolk.
41Brilliant Green Agar (BGA)A selective medium that is used to isolate Salmonella species, but E. coli can grow on it, albeit not as well.
42RPMI 1640 MediumIt is a rich medium that contains inorganic salts, glucose, amino acids, vitamins, and other nutrients that promote the growth of yeast cells.
43m-ENDO AgarE. coli colonies appear as green with a metallic sheen, indicating lactose fermentation.
44Tryptic Soy Agar (TSA)A general purpose medium. E. coli colonies are medium to large, with a shiny moist appearance.
1Sf1Ep mediumCulturing Treponema pallidum, the bacteria that causes syphilis, in vitro is a challenge. T. pallidum is not routinely cultured in the laboratory for diagnostic purposes, in part because it cannot be grown on artificial media. However, a breakthrough in culturing T. pallidum was reported in 2018 when researchers managed to grow the bacterium in a rabbit epithelial cell line (Sf1Ep) using a medium called 'Sf1Ep medium'. It's not used for routine diagnostic purposes, but for research only. The diagnosis involves direct microscopic examination, serologic tests, molecular tests and histopathology.
2Dubos’ MediumA liquid medium that contains a mixture of salts, fatty acids, and polysorbate. When M. tuberculosis grows in this medium, it causes the medium to become turbid.
3Lysine Iron Agar (LIA)Used to determine the ability of an organism to decarboxylate or deaminate lysine and to form hydrogen sulfide. E. coli is typically lysine decarboxylase positive and H2S negative, so you would see a reaction of red/purple slant and purple/red butt with no black precipitate.
4Enterococcosel AgarA selective and differential medium that inhibits the growth of Gram-negative bacteria and distinguishes enterococci based on their ability to grow in the presence of bile and hydrolyze esculin. E. faecalis will form small, black colonies on this medium due to esculin hydrolysis.
5Blood Agar (BA)E. coli colonies on this differential medium are large, circular, gray, moist, and can show β-hemolysis.
6Simmons Citrate AgarUsed for citrate utilization testing. E. coli usually can't utilize citrate as a sole carbon source, so no growth or color change would be expected.
7Sauton’s MediumA liquid medium that lacks detergents, which helps in the formation of corded colonies. When M. tuberculosis grows in this medium, it results in turbidity.
8Proskauer and Beck’s MediumA liquid medium. The growth of M. tuberculosis causes turbidity.
9Middlebrook 7H11 AgarThis is a nutrient-rich medium similar to 7H10 but includes additional pyruvate for energy source, promoting more luxurious growth. The colonies of M. tuberculosis appear small, slightly domed, and rough with a butyrous consistency.
10Loeffler MediumA serum-based medium. M. tuberculosis colonies on Loeffler medium are small, dry, wrinkled, and off-white to yellow.
11Bile Esculin Agar (BEA)A selective and differential medium that differentiates group D Streptococci and Enterococci based on the ability to hydrolyze esculin in the presence of bile. E. faecalis hydrolyzes esculin, leading to the formation of a dark brown or black precipita
12Blood AgarA differential medium used to identify bacteria based on their hemolytic properties. E. faecalis typically shows gamma-hemolysis on this medium, i.e., no hemolysis or change in the color of the medium.
13Sabouraud Dextrose Agar (SDA)It is composed of peptone, dextrose (glucose), and agar. The high dextrose concentration promotes fungal growth, while the acidic pH inhibits bacterial growth.
14Cystine Lactose Electrolyte-Deficient (CLED) AgarE. coli will give lactose-positive yellow colonies.
15Potato Dextrose Agar (PDA)Potato Dextrose Agar (PDA) consists of a nutrient-rich substrate, made from dehydrated Potato Infusion and Dextrose, ideal for robust mycological propagation. Agar provides the solidifying medium. Acidification, typically using sterile tartaric acid, adjusts the pH to 3.5 +/- 0.1 to create a more selective environment by inhibiting bacterial proliferation. Additionally, Chloramphenicol is incorporated as an antimicrobial agent to further suppress bacterial contamination, thereby facilitating the selective isolation of fungi.
16CHROMagar CandidaThis differential medium allows for the isolation and identification of Candida species based on colony color. Candida albicans usually forms green colonies on this medium.
17MacConkey AgarTraditionally used to isolate and differentiate Gram-negative bacilli, E. faecalis can grow on this medium, producing small, round, magenta pink colonies due to lactose fermentation, indicating a positive result.
18Nickerson’s Medium or Bismuth Sulfite Glucose Glycine Yeast (BSGG)This medium is used to stimulate the production of germ tubes, a characteristic of Candida albicans.
19Sula’s MediumA liquid medium containing glycerol, asparagine, and a variety of salts. The growth of M. tuberculosis results in turbidity.
20Nutrient Agar (NA)A non-selective medium. E. coli colonies are usually large, circular, grayish-white, moist, and smooth.
21Mueller Hinton Agar (MHA)Typically used for antibiotic susceptibility testing. E. coli colonies appear pale straw colored.
22Cornmeal Agar with Tween 80It is used for the identification of Candida species by promoting the formation of chlamydospores, which is a characteristic of Candida albicans.
23Phenol Red Mannitol BrothThis is a differential medium, used to determine an organism's ability to ferment mannitol. S. aureus, which can ferment mannitol, will change the medium from red to yellow due to acid production.
24Brilliant Green Agar (BGA)A selective medium that is used to isolate Salmonella species, but E. coli can grow on it, albeit not as well.
25Baird-Parker Agar (BPA)his is a selective medium for the isolation of Staphylococcus species. It has lithium chloride and glycine to inhibit the growth of Gram-negative bacteria and most Gram-positive bacteria except Staphylococcus. Egg yolk emulsion is added to detect lecithinase production and tellurite reduction. S. aureus colonies on BPA are black due to reduction of tellurite, and they exhibit a clear zone due to lecithinase activity on egg yolk.
26Lowenstein-Jensen (LJ) MediumAn egg-based medium that uses malachite green to suppress the growth of other bacteria and glycerol to stimulate the growth of Mycobacterium tuberculosis. The colonies of M. tuberculosis on LJ are non-pigmented, dry, rough, raised, irregular with a wrinkled surface, initially creamy-white, turning yellowish or buff-colored on further incubation.
27Middlebrook 7H9 BrothThis is a liquid medium that contains glycerol and Tween 80, which prevent clumping of mycobacteria. The growth of M. tuberculosis results in turbidity.
28RPMI 1640 MediumIt is a rich medium that contains inorganic salts, glucose, amino acids, vitamins, and other nutrients that promote the growth of yeast cells.
29Urea Agar/BrothE. coli is typically urease negative, so no color change would be expected in this medium.
30Middlebrook 7H10 AgarA selective medium that contains oleic acid, albumin, dextrose, and catalase. The colonies of M. tuberculosis appear small, rough, and buff to white-colored, taking less time to appear compared to egg-based media.
31Eosin Methylene Blue (EMB) AgarA selective and differential medium where E. coli forms distinctive metallic green sheen colonies due to vigorous lactose fermentation.
32BACTECThis is not a traditional medium but a system for detecting the growth of M. tuberculosis by monitoring the release of C14O2 from C14 palmitic acid, which the bacteria metabolize. An increase in radioactive counts in the BACTEC instrument indicates the growth of bacteria.
33Pawlowsky MediumA potato-based medium. Growth of M. tuberculosis may be similar to that seen on the LJ Medium.
34Azide Dextrose BrothA selective medium inhibiting Gram-negative bacteria, used for the isolation of streptococci and staphylococci from mixed samples. E. faecalis will show a positive growth resulting in a turbid appearance of the broth.
35MacConkey Agar (MAC)This selective and differential medium distinguishes lactose fermenters from non-fermenters. E. coli colonies are circular, moist, smooth, and pink.
36Dorset MediumAn egg-based medium. M. tuberculosis colonies appear similar to those on Petragnini Medium: small, round, buff-colored, and taking 3-4 weeks to develop.
37Triple Sugar Iron (TSI) AgarE. coli typically produces an acid butt, acid slant, and gas, with no H2S production, indicating it ferments lactose, sucrose, and glucose.
38Blood Agar (BA)This is a nutrient-rich, differential medium that supports the growth of many organisms. S. aureus forms colonies that are round, smooth, and golden-yellow. This bacterium typically demonstrates β-hemolysis, which is complete lysis of red blood cells, resulting in a clear zone around the colonies. This hemolysis is due to the production of hemolysins by S. aureus.
39Nutrient AgarIt is a general-purpose medium. However, E. faecalis grows poorly on nutrient agar, which means it does not proliferate as well on this medium compared to the others listed, indicating a negative or poor growth.
40Petragnini MediumAn egg-based medium enriched with additional nutrients to promote the growth of Mycobacterium tuberculosis. Colonies of M. tuberculosis are small, round, buff-colored, and typically take 3-4 weeks to appear.
41DNase Test AgarS. aureus produces the enzyme DNase which hydrolyses DNA. When S. aureus grows on this medium, the DNA is broken down, which can be visualised using a hydrochloric acid (HCl) solution: clear zones around the colonies indicate DNA breakdown.
42Todd-Hewitt BrothA liquid enrichment medium used for the cultivation of fastidious organisms such as streptococci and enterococci. E. faecalis will lead to a turbid broth due to microbial growth.
43Tarshis MediumA blood-based medium that can promote the growth of M. tuberculosis. The colonies appear similar to those on the LJ Medium.
44Sorbitol-MacConkey agarA variant of MacConkey agar, used in detecting E. coli O157:H7, which does not ferment sorbitol, unlike most strains of E. coli.
1Sf1Ep mediumCulturing Treponema pallidum, the bacteria that causes syphilis, in vitro is a challenge. T. pallidum is not routinely cultured in the laboratory for diagnostic purposes, in part because it cannot be grown on artificial media. However, a breakthrough in culturing T. pallidum was reported in 2018 when researchers managed to grow the bacterium in a rabbit epithelial cell line (Sf1Ep) using a medium called 'Sf1Ep medium'. It's not used for routine diagnostic purposes, but for research only. The diagnosis involves direct microscopic examination, serologic tests, molecular tests and histopathology.
2Baird-Parker Agar (BPA)his is a selective medium for the isolation of Staphylococcus species. It has lithium chloride and glycine to inhibit the growth of Gram-negative bacteria and most Gram-positive bacteria except Staphylococcus. Egg yolk emulsion is added to detect lecithinase production and tellurite reduction. S. aureus colonies on BPA are black due to reduction of tellurite, and they exhibit a clear zone due to lecithinase activity on egg yolk.
3Phenol Red Mannitol BrothThis is a differential medium, used to determine an organism's ability to ferment mannitol. S. aureus, which can ferment mannitol, will change the medium from red to yellow due to acid production.
4DNase Test AgarS. aureus produces the enzyme DNase which hydrolyses DNA. When S. aureus grows on this medium, the DNA is broken down, which can be visualised using a hydrochloric acid (HCl) solution: clear zones around the colonies indicate DNA breakdown.
5Mannitol Salt Agar (MSA), or Chapman AgarThis is a selective and differential medium. The high concentration of NaCl (~7.5%) selects for halophiles, organisms that can tolerate high salt concentrations, thereby favouring the growth of Staphylococcus species. Mannitol is the differential component: S. aureus ferments mannitol, lowering the pH of the medium, which results in a color change of the pH indicator from red to yellow. Thus, growth of S. aureus is indicated by yellow colonies.
6Blood Agar (BA)This is a nutrient-rich, differential medium that supports the growth of many organisms. S. aureus forms colonies that are round, smooth, and golden-yellow. This bacterium typically demonstrates β-hemolysis, which is complete lysis of red blood cells, resulting in a clear zone around the colonies. This hemolysis is due to the production of hemolysins by S. aureus.
7Sauton’s MediumA liquid medium that lacks detergents, which helps in the formation of corded colonies. When M. tuberculosis grows in this medium, it results in turbidity.
8BACTECThis is not a traditional medium but a system for detecting the growth of M. tuberculosis by monitoring the release of C14O2 from C14 palmitic acid, which the bacteria metabolize. An increase in radioactive counts in the BACTEC instrument indicates the growth of bacteria.
9Sula’s MediumA liquid medium containing glycerol, asparagine, and a variety of salts. The growth of M. tuberculosis results in turbidity.
10Dubos’ MediumA liquid medium that contains a mixture of salts, fatty acids, and polysorbate. When M. tuberculosis grows in this medium, it causes the medium to become turbid.
11Loeffler MediumA serum-based medium. M. tuberculosis colonies on Loeffler medium are small, dry, wrinkled, and off-white to yellow.
12Tarshis MediumA blood-based medium that can promote the growth of M. tuberculosis. The colonies appear similar to those on the LJ Medium.
13Dorset MediumAn egg-based medium. M. tuberculosis colonies appear similar to those on Petragnini Medium: small, round, buff-colored, and taking 3-4 weeks to develop.
14Middlebrook 7H11 AgarThis is a nutrient-rich medium similar to 7H10 but includes additional pyruvate for energy source, promoting more luxurious growth. The colonies of M. tuberculosis appear small, slightly domed, and rough with a butyrous consistency.
15Middlebrook 7H10 AgarA selective medium that contains oleic acid, albumin, dextrose, and catalase. The colonies of M. tuberculosis appear small, rough, and buff to white-colored, taking less time to appear compared to egg-based media.
16Lowenstein-Jensen (LJ) MediumAn egg-based medium that uses malachite green to suppress the growth of other bacteria and glycerol to stimulate the growth of Mycobacterium tuberculosis. The colonies of M. tuberculosis on LJ are non-pigmented, dry, rough, raised, irregular with a wrinkled surface, initially creamy-white, turning yellowish or buff-colored on further incubation.
17Liquid Media (such as Nutrient Broth)E. coli exhibits homogenous turbid growth within 12-18 hours. After prolonged incubation, pellicles may form on the surface of the media.
18Lysine Iron Agar (LIA)Used to determine the ability of an organism to decarboxylate or deaminate lysine and to form hydrogen sulfide. E. coli is typically lysine decarboxylase positive and H2S negative, so you would see a reaction of red/purple slant and purple/red butt with no black precipitate.
19Brilliant Green Agar (BGA)A selective medium that is used to isolate Salmonella species, but E. coli can grow on it, albeit not as well.
20Urea Agar/BrothE. coli is typically urease negative, so no color change would be expected in this medium.
21Triple Sugar Iron (TSI) AgarE. coli typically produces an acid butt, acid slant, and gas, with no H2S production, indicating it ferments lactose, sucrose, and glucose.
22Simmons Citrate AgarUsed for citrate utilization testing. E. coli usually can't utilize citrate as a sole carbon source, so no growth or color change would be expected.
23Tryptic Soy Agar (TSA)A general purpose medium. E. coli colonies are medium to large, with a shiny moist appearance.
24Cystine Lactose Electrolyte-Deficient (CLED) AgarE. coli will give lactose-positive yellow colonies.
25m-ENDO AgarE. coli colonies appear as green with a metallic sheen, indicating lactose fermentation.
26Eosin Methylene Blue (EMB) AgarA selective and differential medium where E. coli forms distinctive metallic green sheen colonies due to vigorous lactose fermentation.
27MacConkey Agar (MAC)This selective and differential medium distinguishes lactose fermenters from non-fermenters. E. coli colonies are circular, moist, smooth, and pink.
28Blood Agar (BA)E. coli colonies on this differential medium are large, circular, gray, moist, and can show β-hemolysis.
29Nutrient Agar (NA)A non-selective medium. E. coli colonies are usually large, circular, grayish-white, moist, and smooth.
30Nickerson’s Medium or Bismuth Sulfite Glucose Glycine Yeast (BSGG)This medium is used to stimulate the production of germ tubes, a characteristic of Candida albicans.
31CHROMagar CandidaThis differential medium allows for the isolation and identification of Candida species based on colony color. Candida albicans usually forms green colonies on this medium.
32RPMI 1640 MediumIt is a rich medium that contains inorganic salts, glucose, amino acids, vitamins, and other nutrients that promote the growth of yeast cells.
33Sabouraud Dextrose Agar (SDA)It is composed of peptone, dextrose (glucose), and agar. The high dextrose concentration promotes fungal growth, while the acidic pH inhibits bacterial growth.
34Nutrient AgarIt is a general-purpose medium. However, E. faecalis grows poorly on nutrient agar, which means it does not proliferate as well on this medium compared to the others listed, indicating a negative or poor growth.
35Blood AgarA differential medium used to identify bacteria based on their hemolytic properties. E. faecalis typically shows gamma-hemolysis on this medium, i.e., no hemolysis or change in the color of the medium.
36MacConkey AgarTraditionally used to isolate and differentiate Gram-negative bacilli, E. faecalis can grow on this medium, producing small, round, magenta pink colonies due to lactose fermentation, indicating a positive result.
37Azide Dextrose BrothA selective medium inhibiting Gram-negative bacteria, used for the isolation of streptococci and staphylococci from mixed samples. E. faecalis will show a positive growth resulting in a turbid appearance of the broth.
38Todd-Hewitt BrothA liquid enrichment medium used for the cultivation of fastidious organisms such as streptococci and enterococci. E. faecalis will lead to a turbid broth due to microbial growth.
39Bile Esculin Agar (BEA)A selective and differential medium that differentiates group D Streptococci and Enterococci based on the ability to hydrolyze esculin in the presence of bile. E. faecalis hydrolyzes esculin, leading to the formation of a dark brown or black precipita
40Tryptic Soy Broth or Agar (TSB/TSA)A general-purpose medium that supports the growth of a broad spectrum of bacteria. E. faecalis on TSA will typically form small, round, and white colonies, indicating a positive growth.