Antifungal action of polyenes is inhibited by added sterols

Antifungal action of polyenes is inhibited by added sterols 

Addition of sterols, particularly those with a 3j3-hydroxyl group, a planar sterol nucleus and a long C17 sidechain, to growth medium inhibited the antifungal action of polyene antibiotics [102,140—143]. Sterol addition prevented polyene uptake by yeasts [143], suggesting that added sterol complexes with the antibiotic, thereby lowering the effective antibiotic concentration, although such a simple interaction has been disputed [142,144]. 

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