4′-Hydroxy-2′-methylacetophenone, an aroma compound of red wines, is isolated from cv. Bobal grape variety. 4′-Hydroxy-2′-methylacetophenone has ciliate toxicity. 4′-Hydroxy-2′-methylacetophenone inhibits the growth of T. pyriformis, with an IC50 of 0.65 mM[1][2]. [1]. GómezGarcía-Carpintero E, et, al. Aroma characterization of red wines from cv. Bobal grape variety grown in La Mancha region. Food Research International. 2011 Jan; 44(1): 61-70. [2]. Schüürmann G, et, al. Stepwise discrimination between four modes of toxic action of phenols in the Tetrahymena pyriformis assay. Chem Res Toxicol. 2003 Aug;16(8):974-87.