Abstract
| - Natamycin is a broad spectrum antimycotic with very low water solubility, which is used to extendthe shelf life of shredded cheese products. β-Cyclodextrin (β-CD), hydroxypropyl β-cyclodextrin (HPβ-CD), and γ-cyclodextrin (γ-CD) were found to form inclusion complexes with natamycin in aqueoussolution. The increase in solubility of natamycin with added β-CD was observed to be linear (type ALphase solubility diagram). The 1:1 stability constant of natamycin:β-CD complex was estimated fromits phase solubility diagram to be 1010 M-1. The phase solubility diagrams of both γ-CD and HPβ-CD exhibited negative deviation from linearity (type AN diagram) and, therefore, did not allow theestimation of binding constants. The water solubility of natamycin was increased 16-fold, 73-fold,and 152-fold with β-CD, γ-CD, and HP β-CD, respectively. The natamycin:CD inclusion complexesresulted in in vitro antifungal activity nearly equivalent to that of natamycin in its free state. Keywords: Natamycin; pimaricin; polyene macrolide; antifungal; preservative; cyclodextrin; inclusioncomplex; solubility
|