NOVELTY - Microorganism biomass, comprises non-living microorganism biomass obtained by cultivating microorganism strains on a cultivation medium comprising lignocellulosic material.    USE - The biomass is useful for preventing or reducing the adverse effects of mycotoxins such as aflatoxin, ochratoxin, trichothecenes, vomitoxin, zearalenone, fumonisin and/ T-2 toxin in animal or human digestive tract, preferably small intestine and/or colon, and useful in the composition as a food or feed topping, food or feed extender or food or feed supplement. The food composition is useful as nutritional product for human use. The method is useful for feeding the animals such as ruminant or monogastric animal, preferably aquaculture, livestock chosen from pig, horse, poultry, cattle, goat and sheep (all claimed).    ADVANTAGE - The biomass binds to a wide range of mycotoxins both at the pH of the acidic stomach and neutral small intestine and colon.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) food or feed composition comprising the microorganism biomass;    (2) method (M1) for improving the well-being and increasing the productivity of an animal, involves feeding the animal a feed composition comprising non-living microorganism biomass;    (3) method (M2) for preparing a feed additive, involves (a) cultivating one or more microorganism(s) in a cultivation medium comprising lignocellulosic material, (b) subjecting the microorganism(s) to a step of cell disruption to obtain non-living biomass of the microorganism(s), (c) isolating a solid phase containing the microbial biomass and residues of lignocellulose of step (b), and (d) drying the microbial biomass obtained from step (c);    (4) method (M3) for detoxifying a mycotoxin contaminated feed or food product, involves (a) providing a feed or food product contaminated with a mycotoxin, (b) providing a feed or food additive, and (c) mixing the feed or food product of (a) with the feed or food additive of (b);    (5) method (M4) for reducing the bioavailability of mycotoxin in a mycotoxin contaminated feed or food product, involves performing the above-mentioned steps (a)-(c); and    (6) method (M5) for feeding an animal, involves feeding the animal with the feed product.