Antimicrobial activity and inhibition of aflatoxin B1 formation by olive plant tissue constituents

Ethanolic extracts of olive callus tissues, added at 0.5 or 1.0% to media on which Aspergillus flavus was 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 and p-, 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/l) showed bactericidal activity towards Pseudomonas aeruginosa and Staphylococcus aureus.     

Diphasic effect of thyrotropin on the uptake and absorption of iodine-131 by thyroid cell culture]

The studies were performed on the primary culture of thyroid cells of newborn pigs. It was shown that thyroid-stimulating hormone (TSH) within the first 12th of its action inhibited uptake and organification of iodine-131. A negative influence of TSH on 131I uptake was retained both with its simultaneous introduction into the culture medium and with 30 min interval as well as when conducting experiments on the 1st, 3d, 5th and 7th days of cultivation. Previous 72h incubation with TSH sufficient for activation of all the links of iodine transport caused an increase in 131I uptake and organification.