Antineurodegenerative, antioxidant and antibacterial activities and phenolic components of Origanum majorana L. (Lamiaceae) extracts of different origin

The aim of this study was to examine chemical composition, as well as antineurodegenerative, antioxidant and antibacterial activity of aqueous and ethanolic extracts of Origanum majorana L. (Lamiaceae) originating from Serbia, Greece, Egypt and Libya. Total phenolics and flavonoids, antioxidant activities, and acetylcholinesterase and tyrosinase inhibitory activities were measured spectrophotometrically. Determination of phenolic compounds in extracts was done using HPLC-DAD technique. Antibacterial activity included determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. The highest phenolic and flavonoid contents were recorded in the ethanolic extract of the Egyptian sample and in aqueous extract of Serbian sample. The HPLC analysis showed high content of rosmarinic acid, with the highest amount found in the ethanolic extract of the plants from Egypt. Water extracts showed prevalently better antioxidant and antineurodegenerative activity in applied tests than the ethanolic extracts. Gram-positive bacterial strains showed higher sensitivity to tested extracts. According to the obtained results, sweet marjoram samples from Serbia and Egypt can be marked as more promising, due to the highest content of total phenolics and flavonoids and the best antioxidant, antibacterial and tyrosinase inhibitory activity.