*2.1. Materials*

Poly(propylene imine) dendrimer second-generation, phenol, 9-chloroacridine, ammonia solution (32%) and anhydrous magnesium sulfate were obtained from Sigma-Aldrich and used as received. All organic solvents: tetrahydrofurane, ethylacetat, chloroform, dichloromethane, acetonitrile, methanol, ethanol, used in this study were used as obtained from Sigma-Aldrich without any additional purifications. Dimethyl sulfoxide (DMSO) for molecular biology was used for antibacterial screening (Sigma–Aldrich). The antibacterial activity of the compounds was tested in vitro with Gram (+) bacterial strain *Bacillus cereus* (*B. cereus*) ATCC 11778 and Gram (−) bacterial strain *Pseudomonas aeruginosa* (*P. aeruginosa*) 1390, and the antifungal activity was screened on fungi strain *Candida lipolytica* (*C. lipolytica*) 7618. Microorganisms were obtained from the collection of the Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria. Before experimental use, cultures from solid medium were sub cultivated in a liquid medium (meat-peptone broth, MPB), incubated (orbital shaker incubator) and used as a source of inoculums for each experiment.
