methyl red


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Related to methyl red: methyl orange

meth·yl red

(meth'il red),
A weakly acid dye used as a pH indicator (red at 4.8, yellow at 6); easily reduced with loss of color and pH readings must be made rapidly.

methyl red

An indicator of pH. It is red at pH 4.4 and yellow at 6.2.
CAS # 493-52-7
See also: red
References in periodicals archive ?
It was found to be positive for glucose, lactose and sucrose fermentation (red colour appeared in test tube) but found to be negative for catalase test (no bubbles were formed), indole test (green layer is formed at the top of test tube), nitrate reduction test, citrate test (green-forest colour in test tube), methyl red Voges-Proskeur test (no red colour appears in test tube), casein hydrolysis test and for starch agar test (no clear zone formation) as shown in Table 1.
Cultural, morphological, and biochemical characteristics of diazotrophic isolates +, Growth; -, no growth; Al, alkaline; Ac, acidic; W, weak SK01 SK02 Cultural Transparent, Transparent, mucoid, mucoid, round, entire, round, entire, raised, large raised, large, dew drop Shape Rods Rods Motility Slow motile Motile Metachromatic + + Catalase test + + Oxidase test - + Methyl red test - Nitrate reduction + + Nitrite reduction + + Citrate utilisation + (W) - Gelatin liquefaction + - Urease production + + Starch hydrolysis - - TSI agar (48 h) Al slant, Al slant, Ac butt Ac butt (w) [H.
The results obtained by using conventional biochemical tests confirmed the significant difficulties for Klebsiella differentiation at the species level, even when reference strains were included and biotyping by other methods; some inconsistent findings were obtained for Methyl red and Voges Proskauer reactions.
3]); 5 mol/L sodium hydroxide (NaOH) prepared from analytical reagent grade; 10 mol/L high-purity hydrochloric acid (HCI); and 1 % (mass fraction) methyl red indicator in ethanol (200 proof).
Identification of Burkholderia multivorans were based on physical characterization such as gram staining and the biochemical characterization such as Catalase test, Oxidase test, Methyl red test, Indole test, Nitrate reduction test, Citrate utilization test outlined in Bergey's Manual of determinative bacteriology (14).
Gram negative colonies that grew on this medium were subjected to biochemical tests (Indole and oxidase production tests, methyl red test, Voges Proskauer test and citrate utilization test) to confirm the colonies as E.
Conventional test were performed by bacterial culture on: Indole (BD), Citrate Simmons (Oxoid), Voges Proskauer (BD), Triple Sugar-Iron (BD), Urea (BD), Motility, Methyl Red (Oxoid) and gas production (BD) (11).
Radiation induced color bleaching of an azo dye; called methyl red in poly (vinyl butyral) has been examined as a high dose dosimeter (12).
Furthermore, the isolate exhibited positive results in oxidase, catalase, indole, methyl red, esculin hydrolysis, nitrate reduction, ONPG test, arginine dehydrolase test, urease, gelatin liquefaction, casein hydrolysis and DNase test presented in table 2.