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Objectives The scope of the present study was to specify the therapeutic potential for neurodegenerative diseases through evaluating cholinesterase and tyrosinase (TYR) inhibitory and antioxidant activity of Lysimachia verticillaris (LV), and to isolate the major compounds considering the most active fraction. Materials and methods The methanol extract (ME) of LV and the chloroform, ethyl acetate (EtOAC), and aqueous fractions obtained from it were used for biological activity and isolation studies. The ME and all fractions were tested for their acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and TYR inhibitory and antioxidant potentials using ELISA microtiter assays. Seven major compounds were isolated from the active EtOAC fraction by semi-preparative high performance liquid chromatography. The structures of the compounds were elucidated by several spectroscopic methods. Results Marked AChE inhibitory activity was observed in the EtOAC fraction (6337±1.74%), BChE inhibitory activity in the ME and EtOAC fraction (85.84±3.01% and 83.82±3.93%), total phenol content in the EtOAC fraction (261.59±3.95 mg equivalent of gallic acid/1 g of extract) and total flavonoid contents in the EtOAC fraction (515.54±2.80 mg equivalent of quercetin/1 g of extract), and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and ferric-reducing antioxidant power values in the aqueous and EtOAC fractions (92.54±0.67%, 92.11±0.30%; 2.318±0.054, 2.224±0.091, respectively). Accordingly, the isolation studies were carried out on the EtOAC fractions. Compounds 1-7 (gallic acid, (+)-catechin, myricetin 3-O-arabinofuranoside, myricetin 3-O-α-rhamnopyranoside, quercetin 3-O-β-glucopyranoside, quercetin 3-O-arabinofuranoside, and quercetin 3-O-α-rhamnopyranoside, respectively) were isolated from the active EtOAC fraction. Conclusion LV may be a potential herbal source for treatment of neurodegenerative diseases based on its strong antioxidant activity and significant cholinesterase inhibition similar to that of the reference.

Lamiaceae is one of the most widespread families in Turkey. The aim of this study was to determine antialzheimer, antidiabetic, antioxidant and antiobesity activities of ethanol extracts of Larnium purpureurm var. purpureum, Origanum onites, Salvia sclarea, S. virgata and Thymus zygioides var. hicaonius. Acetylcholinesterase, butyrylcholinesterase, alpha-amylase, alpha-glucosidase, and pancreatic lipase inhibitory activities were tested for the determination of the activity of these extracts. Furthermore, total antioxidant, ferric-reducing antioxidant power, metal-chelating and N,N-dimethyl-p-phenylendiamine radical scavenging assays were utilized to screen antioxidant activity. Total phenolic content of the extracts were also calculated. Among the tested extracts, T. zygioides var. lycaonius aerial part extract (85.28 +/- 0.89 %) showed the highest inhibitory activity against alpha-glucosidase. The inhibitory activities of all extracts against alpha-amylase were lower than 50 %. S. sclarea leaf extract indicated remarkable butyrylcholinesterase inhibition (51.76 +/- 1.04 %), but all of the plant extracts were inactive against acetylcholinesterase. The Salvia species showed the highest total antioxidant activity. S. sclarea flower (1.34 +/- 0.08) and leaf (1.34 +/- 0.08) extracts showed the highest ferric-reducing antioxidant power activities. Our findings indicated that O. onites, S. sclarea, S. virgata, and T. zygioides var. lycaotrius extracts showed valuable inhibitory activity and emerged as the sources of possible alpha-glucosidase inhibitors for future studies.

Neurodegenerative diseases such as Alzheimer disease and Parkinson disease are among the deadly disorders affecting the elderly population. Unfortunately, effective treatments and medications are still needed to combat these diseases. The ethanol extracts of the raw peeled acorns and acorn coffees from Quercus coccifera prepared by two different methods (boiled-roasted ground and roasted ground) were tested against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYR), the enzymes associated with neurodegeneration. The acorns used in the present study were harvested from wild Quercus coccifera L trees in Kills Province, located in the Eastern Mediterranean region of Turkey in November 2016. Cholinesterase (ChE) and TYR inhibitory activity of the ethanol extracts prepared from raw material and two coffee samples were screened using an ELISA microtiter assay at 2 mg/mL stock concentration. Antioxidant effects of the extracts were also tested for their scavenging activity against DPPH, while total phenol and flavonoid quantities of the extracts were determined spectrophotometrically. Our results indicated that all of the extracts had notable AChE and BChE inhibition, while they were inactive against TYR. The most active extract against ChEs was prepared from the raw material, which led to 65.94 +/- 3.59% and 85.04 +/- 3.83% inhibition against AChE and BChE, respectively. Our data indicate that the fruit extract from Quercus coccifera is a source of promising ChE inhibitors and deserves future study.

The aim of this study was to investigate the effects of various extracts obtained fromPistacia eurycarpa Yalt. on the exact time of appearance of the colonies of Mycobacterium tuberculosis on solid media. For this purpose, the fatty acid compositions of the fixed oils were analyzed using Gas Chromatography – Mass Spectrometry (GC-MS) in the fruit and peels. The fixed oils and the water-soluble extracts obtained from the plant as well as the fatty acids were added either separately or together on the surfaces of the Lowenstein Jensen and Middlebrook 7H11 agar media. Their effects on growth time of 40 strains of M. tuberculosis complex were investigated. Therefore, all of water-soluble extracts accelerated the growth of the mycobacteria in a statistically significant manner in both media. It was observed that the fixed oils and the fatty acids individually did not cause any significant effect on growth duration of the M. tuberculosis strains. Finally, the water-soluble extracts of P. eurycarpa fruit and its peel significantly accelerated the growth of M. tuberculosis by shortening the growth duration of M. tuberculosis at least by one third. Key words: M. tuberculosis, Pistacia eurycarpa, gas chromatography – massspectrometry, growth time