Inhibition of aflatoxin production in groundnut with benzoic acid derivatives and possible toxic effect of their aromatic residues.

Benzoic acid, sodium benzoate, ethyl-rho-aminobenzoate and omicron-hydroxybenzoic acid (salicylic acid) have been found to inhibit mycelial growth and aflatoxin production by A. flavus in groundnut. Benzoic acid (10 mg/g) completely inhibited both mycelial growth and aflatoxin production while sodium benzoate achieved the same result at 24 mg/g of medium. Salicylic acid (20 mg/g) completely inhibited both mycelial growth and aflatoxin in production but ethyl-rho-aminobenzoate inhibited both mycelial growth and aflatoxin production at lower concentrations--3 mg/g of medium for total aflatoxin inhibition and 10 mg/g for complete inhibition of mycelial growth. The results of the possible toxic effects of these aromatic compounds showed that at their effective concentrations they were non-toxic to 1-day-old chicks. Their effects on body and liver weights yielded results similar to the controls. The chicks that were fed aflatoxin-contaminated diets experienced depressed body and liver weights and their livers manifested various pathological changes. Groundnut samples which were supplemented with various concentrations of these aromatic compounds did not give any foul odour. These benzoic acid derivatives could be used, therefore, as fungicides especially against toxigenic A. flavus.