MacConkey's agar refers to a culture medium that is designed to selectively grow Gram-negative bacteria. It contains crystal violet dye, which inhibits certain Gram-positive bacteria.
Macconkey agar consists of agar, lactose, peptone, neutral red dye, crystal violet dye & bile salts. Bile salts inhibit growth of Gram positive bacteria & allow growth of Gram negative bacteria only. It differentiates lactose fermentating Gram negative bacteria from non lactose fermentating Gram negative bacteria.
Crystal violet is a hexamethyl also known as methyl violet 10B This is much darker than 2B, and often darker than 6B. It is used in biological stainang particularly gram staining together with safranin and iodine. Crystal violet was also used to treat strept throat. Doctors used to swab it on the back of your throat.
Touch it to the sterile agar in a plate. If it melts the agar, it is still hot. If it doesn't melt the agar, then it is cool enough.
85C
The size of the molecules.
this MacConkey with crystal violet can grow enterococcus
Lac+ bacteria is acid base color indicator that lowers the pH of the MacConkey agar. The MacConkey agar contains neutral red dye, lactose, peptone, and crystal violet dye.
Staphylococcus will not grow on Mac since crystal violet inhibits the growth of Gram positivesfmchinea: Actually some species of staphylococcus grow on MacConkey's plate including Staphylococcus aureus.
It would allow growth of Gram-positive cocci.
MacConkey agar contains bile salts, lactose, peptone. crystal violet dye, and neutral red dye. The agar appears a medium pink with a copper undertone.
MacConkey agar is designed to grow Gram-negative bacteria and also contains crystal violet dye which inhibits the growth of Gram-positive bacteria. Since S. aureus is Gram-positive it should not grow on MacConkey agar. No. MacConkey agar inhibits MOST of the Gram-positive bacteria. There are some Gram-positive bacteria that can tolerate bile-salt are able to grow in MacConkey agar. Enterococcus and some species of Staphylococcus are able to grow in MacConkey. (lack citation though)
Macconkey agar consists of agar, lactose, peptone, neutral red dye, crystal violet dye & bile salts. Bile salts inhibit growth of Gram positive bacteria & allow growth of Gram negative bacteria only. It differentiates lactose fermentating Gram negative bacteria from non lactose fermentating Gram negative bacteria.
types macconkey agar
gram positive bacteria cannot grow due to the presence of bile salts and crystal violet in maConkey media.
Well, Macconkey Agar II plates have Gram Crystal Violet in them so there are a number of bacterial species that can absorb it and turn "very pink." The way to narrow it down is to identify whether it grows in chains or clusters. But other than that, it is hard to tell.
Undefined.
MacConkey Agar plate