Matrix and composition for microbial culture of gram-positive bacteria

A three-dimensional matrix for microbial culture of gram-positive bacteria, said matrix comprising:

• mechanically disintegrated nanofibrillar cellulose and at least one nutrient source comprising at least one carbon source, at least one nitrogen source, at least one phosphorus source, at least one mineral source and at least one trace element source, wherein the matrix is a hydrogel matrix comprising 0.1-3 wt % of nanofibrillar cellulose;
• and
• living gram-positive bacteria cells suspended homogenously in the hydrogel matrix,
• the hydrogel matrix having a yield stress sufficient to provide mechanical support for stabilizing the bacteria cells to uniformly grow and/or divide therein and for inhibiting sedimentation thereof, wherein the matrix has a liquid viscosity upon shearing such that the matrix is dispensible, pumpable, or injectable, the mechanically disintegrated nanofibrillar cellulose being formed using a refiner, a grinder, a homogenizer, a colloider, a friction grinder, an ultrasound-sonicator, a fluidizer, or a fibrillator.