Abstract: A method of treating a subterranean formation including combining an aqueous fluid, a biomaterial, an enzyme, and a deactivator to form a treatment fluid; and introducing the treatment fluid into the subterranean formation. A method is also disclosed for treating a subterranean formation by preparing a treatment fluid containing an aqueous fluid that contains bacterial and/or fungal cells that produce an enzyme that degrades the biomaterial, a biomaterial, and a deactivator; controlling degradation of the biomaterial by adding an effective amount of the deactivator to the aqueous fluid prior to the preparation of the treatment fluid; and introducing the treatment fluid into the subterranean formation. In the methods, the enzyme degrades the biomaterial and the deactivator is an oxygen-containing arene capable of inhibiting the enzyme from degrading the biomaterial.

Abstract: A well treatment fluid is disclosed containing water, a crosslinkable component, a crosslinker; and an enzyme breaker containing a cellulase enzyme, the well treatment fluid having a total dissolved solids content of at least about 75,000 mg/L up to about 250,000 mg/L. A method of treating a subterranean formation is also disclosed including placing the well treatment fluid in the subterranean formation. It is also disclosed that the well treatment fluid can be a combination of a first fluid including water, the crosslinkable component, the crosslinker, and the enzyme breaker, and having a total dissolved content A with formation water having a total dissolved content B which is higher than the total dissolved content A of the first fluid.

Abstract: A method of treating a subterranean formation including combining an aqueous fluid, a biomaterial, an enzyme, and a deactivator to form a treatment fluid; and introducing the treatment fluid into the subterranean formation. A method is also disclosed for treating a subterranean formation by preparing a treatment fluid containing an aqueous fluid that contains bacterial and/or fungal cells that produce an enzyme that degrades the biomaterial, a biomaterial, and a deactivator; controlling degradation of the biomaterial by adding an effective amount of the deactivator to the aqueous fluid prior to the preparation of the treatment fluid; and introducing the treatment fluid into the subterranean formation. In the methods, the enzyme degrades the biomaterial and the deactivator is an oxygen-containing arene capable of inhibiting the enzyme from degrading the biomaterial.