Sinapic acid is widespread in the plant kingdom (fruits, vegetables, cereal grains, oilseed crops, and some spices and medicinal plants) and as such is common in the human diet.

Sinapic acid fraction isolated from the ethanolic extract of rapeseed was found to be highly effective against the growth of Gram-negative (Escherichia coli, Enterobacter aerogens, and Pseudomonas fluorescens) and Gram-positive (Bacillus subtilis, Bacillus cereus, Streptococcus lactis, and Streptococcus cremoris) bacteria. Antibacterial properties were determined on a solid foundation by the tile method and in liquid cultures. After 48 h of incubation with sinapic acid on a solid foundation, no growth of cells was observed. In the case of liquid cultures, the introduction of 0.6% sinapic acid caused a decrease in the numbers of live cells by 97.7% to 99.1% after 48 h of incubation. For B. cereus, S. lactis, and P. fluorescens it caused total inhibition of their growth.