Antioxidant Properties and Secondary Metabolites Profile of Hyptis colombiana at Various Phenological Stages.

Hyptis colombiana (Lamiaceae family), a species also treated as Cantinoa colombiana in a recently segregated genus from Hyptis, is a perennial herb or subshrub native to the Andes of northern South America. H. colombiana leaves are commonly used in traditional medicine to treat respiratory and digestive illnesses. In this study, H. colombiana plants at different phenological stages (vegetative, flowering, and post-flowering) were harvested to obtain essential oils (EOs) and extracts (from fresh plant materials or post-distillation waste) whose chemical compositions and antioxidant activities were determined. H. colombiana EOs distilled by microwave-assisted hydrodistillation were analyzed by GC/MS/FID, and hydroalcoholic extracts obtained from fresh plant materials or post-distillation waste were analyzed by UHPLC-ESI+/--Orbitrap-MS. The antioxidant activity was evaluated by the ABTS+• and ORAC assays. The principal compounds found in EOs were sesquiterpene hydrocarbons (65%); specifically, (E)-ß-caryophyllene and germacrene D. Pyranone, rosmarinic acid, rutin, and p-hydroxybenzoic acid were the main constituents in H. colombiana extracts. After analyzing the chemical composition and antioxidant activity (ORAC) of EOs and hydroethanolic extracts from flowering H. colombiana plants, minimal variations were found. It is advisable to harvest H. colombiana plants during their flowering stage to acquire EOs and extracts that can be utilized in the agro-industry of EOs and their natural derivatives.

Chemical Composition and In Vitro Antioxidant Activity of Salvia aratocensis (Lamiaceae) Essential Oils and Extracts.

Salvia aratocensis (Lamiaceae) is an endemic shrub from the Chicamocha River Canyon in Santander (Colombia). Its essential oil (EO) was distilled from the aerial parts of the plant via steam distillation and microwave-assisted hydrodistillation and analyzed using GC/MS and GC/FID. Hydroethanolic extracts were isolated from dry plants before distillation and from the residual plant material after distillation. The extracts were characterized via UHPLC-ESI(+/-)-Orbitrap-HRMS. The S. aratocensis essential oil was rich in oxygenated sesquiterpenes (60-69%) and presented τ-cadinol (44-48%) and 1,10-di-epi-cubenol (21-24%) as its major components. The in vitro antioxidant activity of the EOs, measured via an ABTS+• assay, was 32-49 µmol Trolox® g-1 and that measured using the ORAC assay was 1520-1610 µmol Trolox® g-1. Ursolic acid (28.9-39.8 mg g-1) and luteolin-7-O-glucuronide (1.16-25.3 mg g-1) were the major S. aratocensis extract constituents. The antioxidant activity of the S. aratocensis extract, obtained from undistilled plant material, was higher (82 ± 4 µmol Trolox® g-1, ABTS+•; 1300 ± 14 µmol Trolox® g-1, ORAC) than that of the extracts obtained from the residual plant material (51-73 µmol Trolox® g-1, ABTS+•; 752-1205 µmol Trolox® g-1, ORAC). S. aratocensis EO and extract had higher ORAC antioxidant capacity than the reference substances butyl hydroxy toluene (98 µmol Trolox® g-1) and α-tocopherol (450 µmol Trolox® g-1). S. aratocensis EOs and extracts have the potential to be used as natural antioxidants for cosmetics and pharmaceutical products.

New leaf-mining Nepticulidae (Lepidoptera): potential pests of aromatic Lamiaceae plants from equatorial Andes.

Members of the Lamiaceae, or mint family, are used worldwide for medicinal, culinary and/or magical-religious purposes, as well as in pesticides and as ornamental plants. Very little is known about nepticulids, or pygmy moths, as leaf miners of Lamiaceae, but they may be an important component of South American diversity and potential pests of economically-important species of the mint family. In this paper, four new species of leaf-mining Nepticulidae are described from the equatorial Andes of Ecuador: S. mentholica Diskus Stonis, sp. nov., Stigmella aromatica Diskus Stonis, sp. nov., S. odora Diskus Stonis, sp. nov., feeding on Minthostachys mollis (Benth.) Griseb., and S. tomentosella Diskus Stonis, sp. nov., feeding on Clinopodium tomentosum (Kunth) Govaerts. It is hypothesized that host-plant distribution ranges can provide clues to potential distribution ranges of these newly discovered, trophically specialized leaf miners. The leaf mines, adults, and the genitalia of the new species are illustrated with photographs.