In-vitro Inhibition of Human Erythrocyte Acetylcholinesterase by Salvia lavandulaefolia Essential Oil and Constituent Terpenes

Abstract

Sage (Salvia spp) is reputed in European herbal encyclopaedias to enhance memory, and current memory-enhancing/anti-dementia drugs are based on enhancing cholinergic activity by inhibiting cholinesterase. In this study the effects of Salvia lavandulaefolia Vahl. (Spanish sage) essential oil and some of its constituent terpenes on human erythrocyte acetylcholinesterase were examined in-vitro. The main constituents in the essential oil batch used for analysis of cholinesterase inhibition were camphor (27%), 1,8-cineole (13%), alpha- and beta-pinene (10-15%) and bornyl acetate (10%) with other minor constituents (1% or less) including geraniol, limonene, linalool, terpineol and gamma-terpinene. Using the Ellman spectrophotometric method, kinetic analysis was conducted on the interaction of the essential oil and the main monoterpenoids, camphor, 1,8-cineole and alpha-pinene. IC50 values were obtained for the essential oil, 1,8-cineole and alpha-pinene and were 0.03 microL [corrected] mL(-1), 0.67 mM and 0.63 mM, respectively. Camphor and other compounds tested (geraniol, linalool and gamma-terpinene) were less potent (camphor IC50: >10mM). The essential oil, alpha-pinene, 1,8-cineole and camphor were found to be uncompetitive reversible inhibitors. These findings suggest that if the inhibitory activity of the essential oil is primarily due to the main inhibitory terpenoid constituents identified, there is a major synergistic effect among the constituents. Since no single constituent tested was particularly potent, it remains to be determined whether these in-vitro cholinesterase inhibitory activities are relevant to in-vivo effects of the ingestion of S. lavandulaefolia essential oil on brain acetylcholinesterase activity.

Chemical composition and acetylcholinesterase inhibitory activity of essential oils of Myrceugenia myrcioides(Cambess.) O. Berg and Eugenia riedelianaO. Berg, Myrtaceae

“…The monoterpene-rich oil of M. myrcioides presented very low effect, with maximum inhibition of 28.9% in the concentration of 600.0 μg.mL -1 . Some monorterpenes have been demonstrated as potent AChE inhibitors, such as the biclyclic α-pinene and (+)-3-carene (Perry et al, 2000;Miyazawa & Yamafuji, 2005). However, the high levels of α-pinene in M. myrcioides volatile oil did not lead to a considerable enzyme inhibition in the present analysis.…”

“…The volatile oil of Salvia lavandulaefoilia has been shown to inhibit AChE both in vitro and in vivo (Perry et al, 2000;. Additionally, some isolated bicyclic monoterpenes, especially α-pinene and (+)-3-carene, also presented a strong inhibition of this enzyme (Miyazawa & Yamafuji, 2005), as well as some sesquiterpenes, such as α-and β-ionone and nootkatone (Miyazawa et al, 1998a;.…”

Essential oils found in the smoke of "tira-capeta", a cigarette used by some quilombolas living in pantanal wetlands of Brazil

“…Thus, below will be presented the biological activities, described in scientific literature, to the essential oils found in the plants used for produce the "tira-capeta" cigarette, where some correlations tentatively were carried out between these activities and the therapeutical uses reported by the Quilombolas. Perry et al (2000) verified that α-pinene, 1,8-cineole and camphor have uncompetitive and reversible acetylcholinesterase inhibitory activity. It is known that compounds with anticholinesterase properties improved memory and attention in people (Scholey et al, 2008).…”

Evaluation of possible in vitro neurobiological effects of two varieties of Cupressus sempervirens (Mediterranean cypress) through their antioxidant and enzyme inhibition actions

“…In fact, the essential oils of the samples of the two varieties of C. sempervirens used in this study were analyzed by GC-MS in our previously [9] and a-pinene was the main components as follows; CSH-Cone: 66.75%; CSH-Leaf: 56.91%; CSP-Cone: 52.52%; CSP-Leaf: 37.91%. In many previous studies [32][33][34], a-pinene has been shown to inhibit strong cholinesterase inhibitory activity and moderate inhibitory activity of the Cupressus extracts could be related to their a-pinene content, although they are not supposed to contain a-pinene as much as the essential oil per se. Probably, apolar extracts have more possibility to contain this component, where the acetone and dichloromethane extracts were active in our assays.…”