α-Glucosidase Inhibition and Antibacterial Activity of Secondary Metabolites from the Ecuadorian Species Clinopodium taxifolium (Kunth) Govaerts

Abstract

The phytochemical investigation of both volatile and fixed metabolites of Clinopodium taxifolium (Kunth) Govaerts (Lamiaceae) was performed for the first time. It allowed the isolation and characterization of the essential oil and six known compounds: carvacrol (1), squalane (2), uvaol (3), erythrodiol (4), ursolic acid (5), and salvigenin (6). Their structures were identified and characterized by Nuclear Magnetic Resonance (NMR) and Gas Chromatography coupled to Mass Spectroscopy (GC-MS), and corroborated by literature. The essential oil of the leaves was obtained by hydrodistillation in two different periods and analyzed by GC-MS and GC coupled to Flame Ionization Detector (GC-FID). A total of 54 compounds were detected, of which 42 were identified (including trace constituents). The major constituents were carvacrol methyl ether (18.9–23.2%), carvacrol (13.8–16.3%) and, carvacryl acetate (11.4–4.8%). The antibacterial activities were determined as Minimum Inhibition Concentration (MIC) against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa and Micrococcus luteus. The hexane and methanol extracts exhibited activity only against Klebsiella pneumoniae (250 and 500 μg/mL respectively), while the ethyl acetate extract was inactive. The hypoglycemic activity was evaluated by the in vitro inhibition of α-glucosidase. The ethyl acetate (EtOAc) extract showed strong inhibitory activity with IC50 = 24.88 µg/mL, however methanolic and hexanic extracts showed weak activity. As a pure compound, only ursolic acid showed a strong inhibitory activity, with IC50 = 72.71 μM.

Chemical Composition, Enantiomeric Distribution, and Sensory Evaluation of the Essential Oils Distilled from the Ecuadorian Species Myrcianthes myrsinoides (Kunth) Grifo and Myrcia mollis (Kunth) DC. (Myrtaceae)

“…As part of a project aiming to valorize Ecuadorian spontaneous flora [8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25], the chemical composition and sensory profile of Myrcianthes myrsinoides (Kunth) Grifo and Myrcia mollis (Kunth) DC essential oils (EOs) are here reported for the first time. Gas chromatography mass spectrometry (GC-MS) and enantioselective GC-MS were used for the quali-quantitative analysis, and GC-olfactometry (GC-O) to evaluate the odor active compounds.…”

Bioassay guided isolation of mosquito biting deterrent compounds from Strumpfia maritima

“…Consequently, the bioactive fractions were realized and subjected to chromatographic techniques to isolate the active compounds which were characterized by spectroscopic and spectrometric techniques [one‐dimensional (1D) nuclear magnetic resonance (NMR), two‐dimensional (2D) NMR, and high‐resolution electrospray ionization mass spectrometry (HR‐ESI‐MS)]. Out of the active fractions, six compounds; squalene, ursolic acid {[α] 22 D + 91.3 ( c 0.1, CHCl 3 )}, betulonic acid {[α] 22 D + 47.5 ( c 0.1, CHCl 3 )}, cabraleone {[α] 22 D + 73.7 ( c 0.1, CHCl 3 )}, ursolic acid acetate {[α] 22 D + 87.9 ( c 0.1, CHCl 3 )}, and 27‐ p‐E ‐coumaroyloxyursolic acid {[α] 22 D + 7.4 ( c 0.1, CHCl 3 )} . Chemical structures of these compounds are given in Fig.…”

A Novel Chemical Profile of a Selective In Vitro Cholinergic Essential Oil from Clinopodium taxifolium (Kunth) Govaerts (Lamiaceae), a Native Andean Species of Ecuador

“…reported that about 50% of all the phytochemical publications on the Ecuadorian flora referred only to 8 of the 245 botanical families of the native species known in the country [ 2 ]. For this reason, the authors have been involved for years in the description of specialized (secondary) metabolites contained in the Ecuadorian flora, to contribute to the advance in its phytochemical and phytopharmaceutical knowledge [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. Within a project focused on the description of new essential oils (EOs) [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ], the aim of this study is to describe a novel chemical profile of an already known EO, distilled from the aerial parts of Clinopodium taxifolium (Kunth) Govaerts.…”

“…and Satureja lineata Epling. [ 10 , 21 , 22 , 23 ]. This plant is also known with the homonym Clinopodium taxifolium (Kunth) Harley [ 21 ].…”

“…However, specimens have also been described in Bolivia and Peru [ 21 ]. This plant grows at an altitude of 1500–3000 m above sea level [ 23 ] and it is known as Culantrillo de Cerro or Polea de Castilla [ 10 ]. Furthermore, C. taxifolium is used by infusion in folk medicine for treating internal inflammations, flatulence, stomach pain, malaria and cough [ 10 ].…”