D/E (Dey/Engley) Neutralizing Broth is a liquid medium used for neutralizing and determining the bactericidal activity of antiseptics and disinfectants. Tryptone and Yeast Extract provide a source of nitrogen, carbon, and vitamins. Dextrose is an energy source. Bromocresol Purple is used as an indicator for the fermentation of Dextrose by shifting from purple to yellow at acidic pH. Sodium Thiosulfate is incorporated to neutralize chlorine and iodine. Tween 80 neutralizes phenols and formalin. Sodium Thioglycollate neutralizes mercurials. Sodium Bisulfate neutralizes formaldehyde and glutaraldehyde. Lecithin neutralizes quaternary ammonium compounds.