Abstract

The mildew inhibition of nystatin, salicylic acid, sorbic acid and borax were investigated. The results indicated that 30% ethanol, 4% borax and 0.2 % sorbic acid (2.4-dihexadienoic acid) show little inhibiting effect on the 11 strains of mildew which were isolated from the mildewed wet blue.6 1% salicylic acid shows some mildew inhibition, and 10 000μg/ml nystatin is seen to be the best of these low toxicity agents for prevention of mildew. The inhibiting ratios of 1% salicylic acid and 10 000μg/ml nystatin were 27% and 64%, respectively, which showed that 1% salicylic acid and 10 000μg/ml nystatin have better performance in inhibiting mildew than other agents. In view of their performance we concentrated our work on salicylic acid and nystatin.

Culture dish experiments showed that the mixture of 1.5% salicylic acid and 25 000 μg/ml nystatin could inhibit all of the 11 strains of mildew tested. When the concentration was increased, the inhibition capabilities of salicylic acid and nystatin were further enhanced. The mildew tests of salicylic acid and nystatin were conducted on a laboratory scale.

Wet blues have been treated with 1.5% salicylic acid and 25 000μg/ml nystatin, and stored in an incubator at 31°C for more than three months, the mildew could barely be observed on these treated wet blues. The results confirmed the culture dish experiments, which show that salicylic acid and nystatin could be used as mildew inhibitors during the short term storage of wet blues.