Trichoderma citrinoviride EB-104 has recently been developed as a hyper beta-glucosidase producing mutant strain. In the present study, efforts were made to further enhance its enzyme titers using low molecular weight stimulators viz., calliterpinone (a natural plant diterpenoid), DL-2-aminobutyric acid (isomer. of an amino acid, aminobutyric acid) and jasmonic acid (a natural plant growth regulator). Among test stimulators, calliterpinone and DL-2-aminobutyric acid significantly enhanced activities of all three enzymes of cellulase complex i.e., FPase, endoglucanase and beta-glucosidase. A 5.0 and 2.7 fold increase in FPase and endoglucanase activities, respectively, could be achieved by incorporating 12.5 mmol DL-2-aminobutyric acid into fermentation media. On the other hand, more than fivefold enhanced beta-glucosidase activity was evident with 10 mu mol of calliterpinone, raising its activity from 8.28 to 43.38 IU cm (3). This beta-glucosidase activity of T. citrinoviride EB-104 is far higher than that of reported earlier. These test stimulators, which improved enzyme activities of cellulase complex in T. citrinoviride EB-104, may also be explored for enhancing the activities of other fungal enzymes. (C) 2014 Elsevier Ltd. All rights reserved.