Memory-vitalizing effect of twenty-five medicinal and edible plants and their isolated compounds

• The extracts from 25 plant species and 8 compounds were screened in vitro.
• Thymus sipyleus subsp. sipyleus var. sipyleus had the highest iron-chelating effect.
• Onosma nigricaule showed the most promising anti-AChE activity.
• The best anti-BChE was observed with Hypericum capitatum var. capitatum.
• The isolated compounds had none to moderate level of enzyme-inhibiting profiles.

The extracts from 25 plant species from Salvia, Hypericum, Onosma, Thymus, Origanum, Rosa, and Prunus with eight isolated compounds were screened for their memory-vitalizing potential against the enzymes, i.e., acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYR) along with DPPH, DMPD, and NO radicals and iron-chelation capacity using spectrophotometric microtiter assays. The n-hexane:dichloromethane (1:1) extract of Onosma nigricaule roots (63.18 ± 0.56%) and the ethyl acetate extract of the aerial parts of Hypericum capitatum var. capitatum (50.79 ± 3.88%) were the most active toward AChE and BChE, respectively. The highest iron-chelating capacity was found in the n-hexane extract of Thymus sipyleus subsp. sipyleus var. sipyleus, where mostly Labiatae species exhibited better radical scavenging effect. Among the extracts, the roots of O. nigricaule, the aerial parts of Hypericum capitatum var. capitatum and T. sipyleus subsp. sipyleus var. sipyleus could be further evaluated for their memory-vitalizing properties based on different mechanisms.