(EN) Use of an aqueous bio-catalytic composition in the manufacture of paper, the aqueous bio-catalytic composition comprising a fermentation supernatant, which comprises micronutrients, from a yeast culture containing no active enzymes, and one or more nonionic surfactants, wherein the bio-catalytic composition lacks any active enzymes, and wherein the yeast culture is a Saccharomyces cerevisiae culture. The use of the bio-catalytic composition prevents biological film growth and paper spotting, and substantially reduces starch build-up in the manufacture of paper.