Milk-clotting activity of Withania coagulans hairy root extracts

This article presents data on the effect of fruit and hairy root extracts of Withania coagulans Dunal on the process of milk coagulation with a view to its potential application in cheese making. Cheese curd can be obtained by the action of milk-clotting enzymes on the protein fraction of milk. To that end, animal-derived enzymes are widely used. However, the as-produced cheeses may not suit some population groups. In this regard, studying the possibility of using plant proteases in cheese making, as well as their production in plant tissue cultures, appears to be a relevant research task. Hairy roots bioreactor-cultivated using the Agrobacterium rhizogenes soil bacterium contain, as a rule, not only root-specific metabolites but also compounds characteristic of other plant tissues. In this work, protein was extracted from Withania coagulans fruits and hairy roots using various buffers followed by assessing the milk-clotting activity of the extracts using fresh and powdered full cream milk. An animal milk-clotting enzyme was used as a control. The activity of Withania coagulans fruit extract was found to be 5 U/mg of protein. Coagulation carried out with hairy root extracts lasted for at least 6 hours, indicating the presence of a low concentration of milk-clotting enzyme. Since hairy roots of Withania coagulans have been studied in this respect for the first time, further optimization of their cultivation parameters, enzyme extraction, and its application is required.