In vitro studies on the reduction of nitrate by rumen liquor

Abstract A study has been made, using five artificial rumens, of the reduction of nitrate by rumen liquor in the presence of different substrates—cellulose, glucose and dried grass. It has been shown that the presence of easily utilizable carbohydrate (glucose) promotes a speedy reduction of nitrate to nitrite but that other factors—probably hydrogen donators in the dried grass—may also be involved. The further reduction of nitrite to ammonia and the uptake of the latter to form protein have also been noted where these reactions occurred.