Abstract: The invention relates to a method for growth of bacteria, such as Gram negative bacteria and its corresponding supernatant. The bacteria are cultivated without substantial release of endotoxins from the bacteria into the surrounding medium. Thereby the need of purification steps necessary to remove endotoxins are reduced or eliminated such as when the bacteria are producing a product which later on should be administered to a mammal, such as a human. The bacteria are also cultivated without substantial formation of acetic acid. The level of the carbon/energy source is controled during the cultivation and oxygen limitation is avoided through regulation of the temperature. The method may be used for cultivation of bacterial in fermenters.

Abstract: The invention relates to a method for growth of bacteria, such as Gram negative bacteria and its corresponding supernatant. The bacteria are cultivated without substantial release of endotoxins from the bacteria into the surrounding medium. Thereby the need of purification steps necessary to remove endotoxins are reduced or eliminated such as when the bacteria are producing a product which later on should be administered to a mammal, such as a human. The bacteria are also cultivated without substantial formation of acetic acid. The level of the carbon/energy source is controled during the cultivation and oxygen limitation is avoided through regulation of the temperature. The method may be used for cultivation of bacterial in fermenters.

Abstract: A method of biologically purifying waste water rich in carbohydrates or proteins, wherein the waste water is treated in an anaerobic stage while leading off generated methane gas, sludge-bearing water formed being subjected to sludge separation during formation of a first sludge concentrate which is returned to the anaerobic stage, and that the water thus treated is treated in an aerobic stage, sludge-bearing water formed being subjected to slude separation during formation of a second sludge concentrate, of which at least a portion is returned to the aerobic stage, while possible excess is returned to the anaerobic stage, a portion of the first, and possibly also of the second sludge concentrate being led off for disposal.