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.

Enhanced Two-Step Extraction from Biomass of Two Cymbopogon Species Cultivated in Santander, Colombia.

The insertion of circular economy principles into the essential oil (EO) production chain aims to reduce waste generation and make integral use of harvested plant material. Higher profits from integral use with reduced waste generation contribute to the eventual use of the EO value chain as an alternative to illicit crops in Colombia (mostly coca). In this study, Java-type citronella (Cymbopogon winterianus) and palmarosa (C. martinii) plant materials were used in two consecutive processes to obtain EOs and extracts. The residual biomass after EO distillation was subjected to ultrasound-assisted hydroethanolic extraction to afford extracts that contained bioactive compounds. Citronella and palmarosa were distilled with typical EO yields (1.0 ± 0.1% for citronella; 0.41 ± 0.06% for palmarosa; n = 5) either through hydrodistillation assisted by microwave radiation or through steam distillation, and their composition (determined via GC/FID/MS analysis) and physicochemical parameters fell within their ISO standard specifications. The concentration of citronellal, the major compound of citronella oil, was 500 ± 152 mg/g. Geraniol, the main component of palmarosa oil, was found at 900 ± 55 mg/g. The citronella and palmarosa hydroalcoholic extracts (4-11% yield) were analyzed with UHPLC-ESI-Orbitrap-MS, which permitted the identification of 30 compounds, mainly C-glycosylated flavones and hydroxycinnamic acids. Both extracts had similar antioxidant activity values, evaluated using the ABTS+● and ORAC assays (110 ± 44 µmol Trolox®/g extract and 1300 ± 141 µmol Trolox®/g extract, respectively).

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.

Chemical Characterization and Determination of the Antioxidant Properties of Phenolic Compounds in Three Scutellaria sp. Plants Grown in Colombia.

Plants of the genus Scutellaria (Lamiaceae) have a wide variety of bioactive secondary metabolites with diverse biological properties, e.g., anti-inflammatory, antiallergenic, antioxidant, antiviral, and antitumor activities. The chemical composition of the hydroethanolic extracts, obtained from dried plants of S. incarnata, S. coccinea, and S. ventenatii × S. incarnata, was determined by UHPLC/ESI-Q-Orbitrap-MS. The flavones were found in a higher proportion. Baicalin and dihydrobaicalein-glucuronide were the major extract components in S. incarnata (287.127 ± 0.005 mg/g and 140.18 ± 0.07 mg/g), in S. coccinea (158.3 ± 0.34 mg/g and 51.20 ± 0.02 mg/g), and in S. ventenatii × S. incarnata (186.87 ± 0.01 mg/g and 44.89 ± 0.06 mg/g). The S. coccinea extract showed the highest antioxidant activity in the four complementary techniques employed to evaluate all extracts: ORAC (3828 ± 3.0 µmol Trolox®/g extract), ABTS+• (747 ± 1.8 µmol Trolox®/g extract), online HPLC-ABTS+• (910 ± 1.3 µmol Trolox®/g extract), and ß-carotene (74.3 ± 0.8 µmol Trolox®/g extract).

Color, Antioxidant Capacity and Flavonoid Composition in Hibiscus rosa-sinensis Cultivars.

Hibiscus rosa-sinensis plants are mainly cultivated as ornamental plants, but they also have food and medicinal uses. In this work, 16 H. rosa-sinensis cultivars were studied to measure their colorimetric parameters and the chemical composition of hydroethanolic extracts obtained from their petals. These extracts were characterized using UHPLC-ESI+-Obitrap-MS, and their antioxidant activity was evaluated using the ORAC assay. The identified flavonoids included anthocyanins derived from cyanidin, glycosylated flavonols derived from quercetin and kaempferol, and flavan-3-ols such as catechin and epicatechin. Cyanidin-sophoroside was the anthocyanin present in extracts of lilac, pink, orange, and red flowers, but was not detected in extracts of white or yellow flowers. The total flavonol concentration in the flower extracts was inversely proportional to the total anthocyanin content. The flavonol concentration varied according to the cultivar in the following order: red < pink < orange < yellow ≈ white, with the extract from the red flower presenting the lowest flavonol concentration and the highest anthocyanin concentration. The antioxidant activity increased in proportion to the anthocyanin concentration, from 1580 µmol Trolox®/g sample (white cultivar) to 3840 µmol Trolox®/g sample (red cultivar).

Hallazgo de diclofenaco en un producto fitoterapéutico a base de caléndula comercializado en Colombia / Finding diclofenac in a marigold-based phytotherapeutic product marketed in Colombia

Resumen Introducción: la consulta de un particular que trajo un producto fitoterapéutico a base de caléndula cuyo consumo le causó fuertes reacciones adversas, originó esta investigación sobre la composición de este producto. Objetivo: caracterizar la composición química de muestras de lotes diferentes de un producto comercial denominado fitoterapéutico a base de caléndula (Calendula officinalis) (PFC) comercializado en Colombia. Metodología: se analizaron tabletas de ocho cajas del PFC de cuatro lotes diferentes de producción (2017 y 2018). Se llevó a cabo el análisis de espacio de cabeza (HS) de tabletas por microextracción en fase sólida (SPME), con una fibra PDMS/DVB (65 µm), expuesta al HS de la muestra durante 30 min a 50 °C. Las fracciones volátiles se analizaron por cromatografía de gases acoplada a espectrometría de masas (GC/MS). Los extractos de tabletas obtenidos con mezcla de metanol:agua (1:1, v/v) se analizaron por cromatografía líquida (LC) de alta (HPLC) y ultra-alta eficiencia (UHPLC), con detectores de arreglo de diodos (DAD) y espectrometría de masas de alta resolución (HRMS), respectivamente; la cuantificación de diclofenaco se hizo por calibración con patrón externo y por adición de estándar. Los espectros de masas de baja y alta resolución y patrones de fragmentación de las sustancias detectadas se estudiaron, usando GC/HRMS y LC/HRMS-Orbitrap. Resultados: en tabletas analizadas por HSSPME, se encontraron monoterpenoides y sesquiterpenoides de origen vegetal, ftalatos, residuos de solventes (2-cloroetanol, etilenglicol) y sustancias químicas intermediarias en la síntesis de diclofenaco (2,6-dicloroanilina y 2,6-cloro-N-fenil-bencenamina). En los cromatogramas, obtenidos por GC/MS de los extractos de tabletas obtenidos con diclorometano, se detectaron diclofenaco, sus impurezas A, B y C, los ésteres de diclofenaco y algunas otras impurezas. Diclofenaco en cantidad ca. 40 mg (7-8%) se cuantificó por HPLC en tabletas (> 70 analizadas) escogidas al azar de ocho cajas del PFC, adquirido en el mercado local de Bucaramanga (Colombia). Conclusión: en cada tableta analizada se determinaron alrededor de 40 mg del compuesto sintético diclofenaco (sustancia no declarada en la etiqueta del producto) y en ninguna se detectaron ésteres de los triterpenoides oleanano o faradiol, constituyentes del extracto de caléndula que poseen actividad antiinflamatoria; se encontraron algunos flavonoides comunes a muchas plantas, en cantidades mil veces menores que la de diclofenaco.

Abstract Introduction: The consultation of a person who brought a marigold-based phytotherapeutic product whose consumption caused strong adverse reactions, originated this investigation of the composition of this product. Objective: to characterize the chemical composition of samples of different lots of a commercial product called calendula-based phytotherapeutic product (Calendula officinalis) (PFC) commercialized in Colombia. Methodology: Tablets of eight packs of the phytotherapeutic product from four different production batches (2017 and 2018) were analyzed. Headspace analysis (HS) of tablets by solid phase microextraction (SPME) was carried out with a PDMS/ DVB fiber (65 µm), exposed to the HS of the sample for 30 min at 50 °C. Volatile fractions were analyzed by gas chromatography coupled to mass spectrometry (GC/MS). Tablet extracts obtained with methanol:water mixture (1:1, v / v) were analyzed by liquid chromatography (LC) of high (HPLC) and ultra-high performance (UHPLC) with diode array (DAD) and high-resolution mass spectrometric (HRMS) detectors, respectively; diclofenac was quantified by external calibration and standard addition. Low- and high-resolution mass spectra (MS, HRMS) and fragmentation patterns of detected substances were studied, using GC/HRTOF-MS and LC/HRMS-Orbitrap. Results: in tablets analyzed by HS-SPME, monoterpenoids and sesquiterpenoids of plant origin, phthalates, solvent residues (2-chloroethanol, ethylene glycol) and intermediary chemicals in diclofenac synthesis (2,6-dichloroaniline and 2,6- chloro-N-phenyl-benzenamine) were found. In the chromatograms (GC/MS) of the extracts of tablets obtained with organic solvent (dichloromethane), diclofenac, its impurities A, B and C, diclofenac esters, and some other compounds were detected; diclofenac quantification by HPLC found amounts of ca. 40 mg (7 - 8%) in tablets (> 70 analyzed) chosen at random from eight packs of the calendula-based phytotherapeutic product, purchased in the local market in Bucaramanga (Colombia). Conclusion: each analyzed tablet contained around 40 mg of the synthetic compound diclofenac (substance not declared in the product's label) and no tablet contained detectable amounts of esters of the triterpenoids oleanane or faradiol, which are calendula extract constituents that possess antiinflammatory activity; a few flavonoids that are common to many plants were found in amounts a thousand times smaller than that of diclofenac.

Chromatographic and mass spectrometric characterization of essential oils and extracts from Lippia (Verbenaceae) aromatic plants.

Analytical methodologies based on GC and HPLC were developed for the separation and quantification of carnosic acid, ursolic acid, caffeic acid, p-coumaric acid, rosmarinic acid, apigenin, luteolin, quercetin, kaempferol, naringenin, and pinocembrin. These methods were used to characterize essential oils and extracts obtained by solvent (methanol) and by supercritical fluid (CO(2)) extraction from stems and leaves of Lippia (Verbenaceae family) aromatic plants (Lippia alba, Lippia origanoides, Lippia micromera, Lippia americana, Lippia graveolens, and Lippia citriodora). Supercritical CO(2) extraction isolated solely pinocembrin and narigenin from three L. origanoides chemotypes. Solvent extracts possessed a more varied composition that additionally included apigenin, quercetin, and luteolin. Solvent extraction afforded higher overall flavonoid yields from all species in comparison with supercritical CO(2) extraction. Pinocembrin was determined in L. origanoides extract at a concentration of 30 mg/g of plant material, which is more than ten times higher than the amount at which polyphenols are regularly found in aromatic plant extracts.

Lippia origanoides chemotype differentiation based on essential oil GC-MS and principal component analysis.

Chromatographic (GC/flame ionization detection, GC/MS) and statistical analyses were applied to the study of essential oils and extracts obtained from flowers, leaves, and stems of Lippia origanoides plants, growing wild in different Colombian regions. Retention indices, mass spectra, and standard substances were used in the identification of 139 substances detected in these essential oils and extracts. Principal component analysis allowed L. origanoides classification into three chemotypes, characterized according to their essential oil major components. Alpha- and beta-phellandrenes, p-cymene, and limonene distinguished chemotype A; carvacrol and thymol were the distinctive major components of chemotypes B and C, respectively. Pinocembrin (5,7-dihydroxyflavanone) was found in L. origanoides chemotype A supercritical fluid (CO(2)) extract at a concentration of 0.83+/-0.03 mg/g of dry plant material, which makes this plant an interesting source of an important bioactive flavanone with diverse potential applications in cosmetic, food, and pharmaceutical products.

Reactividad quíiica en la alquilación intramoleular de friedel-crafts de orto--alilanillnas tv-bencilo sustituidas / Chemical reaciviity in the intramolecular fridel-crafts alkylation of tv-bennzyl substituted ortho -allylanilfnes / Reatividade uímiica na alquilação intramoleclar do friedel-crafts de orto-aalilanilines v-bencil substituídas

En este trabajo se reporta el estudio experimental de la alquilación intramolecular de Friedel-Crafts de orto-alilanilinas N-bencilo sustituidas, que explica desde los puntos de vista cinético y termodinâmico la formación de dihidrodibenzo [b,e]azepinas y tetrahidrodibenzo[b, ƒ] azocinas. El seguimiento de los cambios en concentración resultantes del tratamiento en condiciones heterogéneas se llevó a cabo por Cromatografía de Gases-Detector de Ionización en Llama (CG-DILL), mientras que la espectroscopia Ultravioleta-Visible (UV-Vis) y el análisis quimiométrico con el Método Multivariante de Resolución de Curvas-Mínimos Cuadrados Alternados (MMRC-MCA) se usaron para examinar los efectos de las condiciones de reacción en fase homogénea e in situ. Con los resultados obtenidos se puede concluir que la supervisión de parámetros, tales como constantes de velocidad y energías de activación, hizo posible evidenciar los efectos de sustituyen-te, temperatura, velocidad de agitación y concentración, sobre la velocidad y re-gioselectividad de la reacción.

In this work, experimental studies of intramolecular Friedel-Crafts alkylation of N-benzyl sustituted ortho-allylanilines are reported; the results explain the formation of both dihydrodibenz[b,e]azepine and tetrahydrodibenz[b,ƒ]azocine isomers from kinetic and thermodynamic points of view. The concentration changes resulting from treatment under heterogeneous conditions were followed by Gas Chromatography-Flame Ionization Detector (GC-FID), while Ultraviolet-Visible (UV-Vis) spectroscopy with Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) chemometric analysis were used for analysis of the effects of reaction conditions in homogeneous phase and in-situ. With the obtained results could be conclude that the supervision of parameters such as rate constants and activation energies proved the effects of substituent, temperature, agitation speed and concentration on reaction velocity and regioselectivity.

No trabalho reporta-se o estudo experimental da alquilação intramolecular de Friedel-Crafts de orto-alil-anilines N-bencil substituídas o quais explicam desde a cinética e a termodinâmica, a produção de dihidrodibenzo[b,e]azepinas e tetrahidrodibenzo[b,ƒ]azocinas. O procedimento experimental nas condições erogén foi estabelecida mediante GC-FID e a espectroscopia UV-Vis com análise quimiométrico MCR-ALS foi usada para estabelecer as condições da reação na fase homogênea e in situ. Baseados nos resultados obtidos pode-se concluir como variação dos parâmetros constate de velocidade e energia de ativação fize possível evidenciar os efeitos do substituinte, temperatura, velocidade de agitação e concentração, sobra a velocidade e seletividade da reação.

Inhibitory effect of essential oils obtained from plants grown in Colombia on yellow fever virus replication in vitro.

BACKGROUND: An antiviral drug is needed for the treatment of patients suffering from yellow fever. Several compounds present in plants can inactive in vitro a wide spectrum of animal viruses. AIM: In the present study the inhibitory effect of essential oils of Lippia alba, Lippia origanoides, Oreganum vulgare and Artemisia vulgaris on yellow fever virus (YFV) replication was investigated. METHODS: The cytotoxicity (CC(50)) on Vero cells was evaluated by the MTT reduction method. The minimum concentration of the essential oil that inhibited virus titer by more than 50% (MIC) was determined by virus yield reduction assay. YFV was incubated 24 h at 4 degrees C with essential oil before adsorption on Vero cell, and viral replication was carried out in the absence or presence of essential oil. Vero cells were exposed to essential oil 24 h at 37 degrees C before the adsorption of untreated-virus. RESULTS: The CC(50) values were less than 100 microg/mL and the MIC values were 3.7 and 11.1 microg/mL. The CC(50)/MIC ratio was of 22.9, 26.4, 26.5 and 8.8 for L. alba, L origanoides, O. vulgare and A. vulgaris, respectively. The presence of essential oil in the culture medium enhances the antiviral effect: L. origanoides oil at 11.1 microg/mL produced a 100% reduction of virus yield, and the same result was observed with L. alba, O. vulgare and A. vulgaris oils at 100 microg/mL. No reduction of virus yield was observed when Vero cells were treated with essential oil before the adsorption of untreated-virus. CONCLUSION: The essential oils evaluated in the study showed antiviral activities against YFV. The mode of action seems to be direct virus inactivation.

Sampling volatile compounds from natural products with headspace/solid-phase micro-extraction.

Recent advances in the development of analytical methods based on headspace/solid-phase micro-extraction (HS/SPME) of natural aroma compounds are reviewed, with special emphasis on increasing reproducibility. Representative examples of applications of HS/SPME to the determination of components at trace levels, strategies for fiber selection, and improvement of SPME sampling conditions are presented. Examples of applications to quality control and sample classification, based on aroma profiling were selected to highlight the use of multivariate statistical methods.

HS-SPME determination of volatile carbonyl and carboxylic compounds in different matrices.

Specific chromatographic methodologies are developed for the analysis of carboxylic acids (C(2)-C(6), benzoic) and aldehydes (C(2)-C(10)) of low molecular weight in diverse matrices, such as air, automotive exhaust gases, human breath, and aqueous matrices. For carboxylic acids, the method is based on their reaction with pentafluorobenzyl bromide in aqueous solution, followed by the separation and identification of the resultant pentafluorobenzyl esters by means of headspace (HS)-solid-phase microextraction (SPME) combined with gas chromatography (GC) and electron capture detection (ECD). Detection limits in the microg/m(3) range are reached, with relative standard deviation (RSD) less than 10% and linear response (R(2) > 0.99) over two orders of magnitude. The analytical methodology for aldehydes is based on SPME with simultaneous derivatization of the analytes on the fiber, by reaction with pentafluorophenylhydrazine. The derivatization reagent is previously deposited on the SPME fiber, which is then exposed to the gaseous matrix or the HS of the sample solution. The pentafluorophenyl hydrazones formed on the fiber are analyzed selectively by means of GC-ECD, with detection limits in the ng/m(3) range, RSD less than 10%, and linear response (R(2) > 0.99) over two orders of magnitude.

Evaluación de l actividad antioxidante de aceies esenciales en emulsiones deggradadas por radiación ultravioleta / Evaluation of nttioxidant activity of essentia oils in emulsions degraded by ultraviolet radiation

En este trabajo se evaluaron las actividades antioxidantes in vitro de los aceites esenciales de Origanum vulgare L., Rosmarinus officinalis L. y Coriandrum sativum L., en emulsiones de agua en aceite (Ag/Ac) y aceite en agua (Ac/Ag), sometidas al deterioro oxidativo por medio de la radiación ultravioleta A-visible (UVAVIS). En la emulsión de Ag/Ac (margarina), el aceite esencial de orégano presentó actividad antioxidante superior a la del cilantro y el romero, e incluso a la de la vitamina E, en concentraciones de 1, 10 y 20 g/kg. Se estableció además, que la acción antioxidante in vitro de los aceites esenciales de orégano y cilantro aumentaba con su concentración en la margarina. Por último, el aceite esencial de orégano presentó una acción protectora más baja en la emulsión de Ac/Ag.

In this work, the antioxidant activities of Origanum vulgare L., Rosmarinus officinalis L. and Coriandrum sativum L. essential oils were evaluated in water in oil (W/O) and oil in water (O/W) emulsions subjected to oxidative deterioration caused by exposure to UVA-VIS radiation. O. vulgare L. essential oil exhibited a higher antioxidant protection followed by the C. sativum L. and R. officinalis L. essentials oils in W/O emulsion (margarine). The O. vulgare L. essential oil has an antioxidant activity higher than C. sativum L., R. officinalis and vitamin E at 1, 10 and 20 g/kg. Moreover, in vitro antioxidant activities of the O. vulgare L., and C. sativum L. increased with their concentration in W/O emulsion (margarine). Finally, O. vulgare L. essential oil antioxidant activity was lower in O/W emulsion.

SPME determination of volatile aldehydes for evaluation of in-vitro antioxidant activity.

The in-vitro antioxidant activity of natural (essential oils, vitamin E) or synthetic substances ( tert-butyl hydroxy anisole (BHA), Trolox) has been evaluated by monitoring volatile carbonyl compounds released in model lipid systems subjected to peroxidation. The procedure employed methodology previously developed for the determination of carbonyl compounds as their pentafluorophenylhydrazine derivatives which were quantified, with high sensitivity, by means of capillary gas chromatography with electron-capture detection. Linoleic acid and sunflower oil were used as model lipid systems. Lipid peroxidation was induced in linoleic acid by the Fe2+ ion (1 mmol L-1, 37 degrees C, 12 h) and in sunflower oil by heating in the presence of O2 (220 degrees C, 2 h). The change in hexanal (the main lipoxidation product) concentration found in the lipid matrix subjected to oxidation with and without the substance being tested was used to calculate the antioxidant protection effect. These procedures were employed to evaluate the antioxidant activity of the essential oils of cilantro ( Coriander sativum L.), fennel ( Foeniculum vulgare Mill.), rosemary ( Rosmarinus officinalis L.), "salvia negra" ( Lepechinia schiedeana), and oregano ( Origanum vulgare L.), and the well-known antioxidants BHA, vitamin E, and Trolox, its water-soluble analog. In the sunflower oil system, the essential oils had a stronger protective effect against lipid peroxidation than BHA, vitamin E, and Trolox within the range of concentrations examined (1-20 g L-1). The highest protecting effect, corresponding to a 90% drop in hexanal release, was observed for cilantro oil at 10 g L-1.