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.
The indicator, two drops of methyl red indicator, was added just before the start of the titration.
Positive results for catalase and methyl red tests and negative results for oxidase, indole utilization tests and Voges-Proskauer tests were recorded.
Their growth on Eosin methylene blue agar with appearance of green metallic sheen, positive for indole and oxidase production, methyl red test and negative Voges-Proskauer and citrate utilization tests confirmed these isolates as those of 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).
In a MFC, 106 mWcm-2 current density was generated which increased to 207 mWcm-2 and 164 mWcm-2with introduction of mediator methyl red and methyl orange respectively [19].The decrease in solution resistance Rs was observed from 410 a| to 282 a| with the addition of methyl orange and to 153 a| with methyl red.
On the basis of biochemical characterization the five isolates were found to be non-motile, also gave positive result for nitrate reduction test and methyl red test, while negative result was obtained for indole test.
Tenders are invited for supply of chemicals and glasswares items Activated CharcoalP Free,Ammonium acetate, Azomithen H, Barium chloride, Boric acid, Bromocresol green, Calcium chloride, Glacial acetic acid, Gum acacia, Methyl Red indicator, Potassium Chloride,Potassium sulphate, Sodium Hydroxide, Triethanol amyne, Zinc metal etc.
Methyl orange, methyl red and Congo red are the dyes being used as acid base indicators because of their ability to act as weak acids or bases.
Hsueh and Chen (2007) reported MR as the most difficult dye to degrade due to charged carboxyl group on Methyl red at ortho position to azo bond, inhibiting decolorization activity.
Radiation induced color bleaching of an azo dye; called methyl red in poly (vinyl butyral) has been examined as a high dose dosimeter (12).