Chemical profile, acetylcholinesterase, butyrylcholinesterase, and prolyl oligopeptidase inhibitory activity of Glaucium corniculatum subsp. refractum

Abstract Papaveraceae is one of the prominent alkaloid-containing families, and plants of the genus Glaucium (Papaveraceae) are known for their bioactive alkaloids. Glaucium species have been used in traditional medicine in Turkey as an analgesic, narcotic, sedative, and antitussive. In this study, it was planned to evaluate the inhibitory activity of an alkaloidal extract of Glaucium corniculatum subsp. refractum on acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and prolyl oligopeptidase (POP), as well as exploring the chemical profile of the plant by using Gas Chromatography-Mass Spectrometry (GC-MS). The AChE, BuChE and POP inhibition activities of the alkaloidal extract of G. corniculatum subsp. refractum were determined spectrophotometrically. A rapid GC-MS method was used to identify alkaloids that could be responsible for these inhibition activities. In total, eleven alkaloids were identified in the alkaloid extract of the plant by GC-MS. Allocyptopine (52.92%) and protopine (25.38%) were found as the major constituents. The alkaloidal extract of G. corniculatum subsp. refractum showed potent AChE inhibitory activity (IC50:1.25 µg/mL) and BuChE inhibitory activity (IC50: 7.02 µg/mL). The extract also showed a remarkable inhibitory effect on POP with an IC50 value of 123.69 µg/mL. This study presents the first GC-MS investigation and POP inhibitory activity of G. corniculatum subsp. refractum.

Application of HPLC-DAD for the quantification of Lycorine in Galanthus elwesii Hook

ABSTRACT In the present study, a reversed-phase high-performance liquid chromatographic method has been used for the quantitative determination of lycorine in the aerial parts and bulbs of G. elwesii Hook. A simple method for the extraction of lycorine in low mass plant samples was employed utilizing pre-packed columns with diatomaceous earth (Extrelut(r)). The chromatographic separation was performed using an isocratic system with a mobile phase of trifluoroacetic acid-water-acetonitrile (0.01:92.5:7.5, v/v/v) applied at a flow rate 1 mL min-1 using diode array detector. The content of lycorine in the bulbs and aerial parts of G. elwesii collected from Demirci (Manisa) was found as 0.130 and 0.162 %, respectively. Additionally, in the bulbs of the specimens collected from Sogucak (Balikesir), lycorine was quantified as 0.055 %, whereas in the aerial parts, it was determined as 0.006 %. The method was validated partially with respect to system specificity, linearity, accuracy, precision, limits of detection (LOD) and quantitation (LOQ). Validation procedures displayed that the method was specific, accurate and precise.