Bu çal mada, Pseudevernia furfuracea var. furfuracea ve Parmelina tiliaceae likenlerinin de i ik çözücülerle haz rlanm ayr ayr ve kombine ekstraktlar n n gram pozitif ve gram negatif bakterilere kar antimikrobiyal aktiviteleri ara t r lm t r. Deneyler sonucunda, liken ekstraktlar n n gram pozitif bakterilere etki etti i ancak gram negatif bakterilere etki etmedi i gözlenmi tir. Kombine edilmi liken ekstraktlar n n birbirlerinin antimikrobiyal aktiviteleri üzerindeki antogonistik ve sinerjistik etkileri de ara t r lm ve Parmelina tiliaceae likeninin Pseudevernia furfuracea var. furfuracea likeni üzerine antogonistik etki gösterdi i görülmü tür.

In this study, antimicrobial activity of single or combine extracts of Pseudevernia furfuracea var. furfuracea and Parmelina tiliaceae which were prepared in different solvents were investigated against gram positive and gram negative bacteria. Extracts of lichens have shown antimicrobial activity against gram positive bacteria but they have no antimicrobial activity against gram-negative bacteria in test results. In addition, antogonistic and synergistic effects of combined extracts of lichen were investigated .It was seen that extracts of Parmelina tiliaceae have antogonistic effect on extracts of Pseudevernia furfuracea var. furfuracea.