Antimicrobial activity and inhibition of aflatoxin B1formation by olive plant tissue constituents

摘要

Ethanolic extracts of olive callus tissues, added at 0.5 or 1.0 to media on whichAspergillus flavuswas grown, inhibited aflatoxin production by 90 without inhibiting the fungal growth. The extract was found to contain mainly caffeic acid and, to a lesser extent, catechin and coumarins. The fungicidal and bactericidal activity of caffeic acid, catechin, coumarin andp‐, o‐or m‐coumaric acid were tested and only caffeic acid and o‐coumaric acid inhibited aflatoxin production. The inhibitory effect had no correlation with the growth of the fungus. Only coumarin at 10 mmol/1 totally inhibited fungal growth. Of the phenolic constituents of callus tissues tested, catechin and caffeic acid (10 mmol/1) showed bactericidal activity towardsPseudomonas aeruginosaandStaphylococcus