ABCB1 and lymphoma: Their ability to inhibit P-glycoprotein (the efflux pump responsible for the multidrug resistance of the used cell line) of mouse lymphoma cells containing the human efflux pump gene MDR1 and their antibacterial activity was studied [19,20]: uvaol 3 was the most effective and promising compound in the reversal of multidrug resistance in MDR mouse lymphoma cell line, whilst oleanolic acid 2 presented high antibacterial activity against a large number of bacterial strains [20].