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)-β-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 β-carotene (74.3 ± 0.8 µmol Trolox^®/g extract).

Perioperative in Intensive Medicine of reconstructive surgery and burned patients

Burned patients may need prolonged admissions in the Intensive Care Service, both for initial care and for the pre and postoperative treatment of the multiple surgeries they require. The initial resuscitation of critically burned patients requires adequate monitoring to calculate the fluid therapy necessary to replenish the losses and ensure tissue perfusion, but without excesses that increase interstitial edema. In addition, monitoring can evaluate the systemic inflammatory response that can lead to shock and organic dysfunctions. After this initial phase we will find a critical patient who requires multiple reinterventions in non-optimal situations, so he will need special care over a long period of time. In addition, the Intensive Care Service offers specific postoperative care for reconstructive surgery and the transplantation of composite tissues (upper limb and face) in which its success depends on a rigorous control through adequate monitoring and treatment.

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.

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.

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 (CC₅₀) 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°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°C before the adsorption of untreated-virus.

Results

The CC₅₀ values were less than 100 μg/mL and the MIC values were 3.7 and 11.1 μg/mL. The CC₅₀/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 μg/mLproduced a 100% reduction of virus yield, and the same result was observed with L. alba, O. vulgare and A. vulgaris oils at100 μg/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.

Effect of freezing on Fossomatic cell counting in ewe milk

Using the Fossomatic method, a total of 10,072 analytical somatic cell count (SCC) observations were carried out on 4760 aliquots taken from 70 individual ewe milk samples with the objective of studying whether freezing showed significant differences of SCC in comparison with refrigeration, according to different analytical conditions. These conditions were four preservation procedures (without preservation, potassium dichromate, azidiol, and bronopol), two storage temperatures (refrigeration and freezing), five milk ages within storage (24 h postcollection in refrigeration, and 24 h, 15, 30, and 60 d postcollection in freezing), two thawing types (rapid and slow), and two analytical temperatures (40 and 60 degrees C). Preservation, storage, and analytical temperature, type of thawing and milk age within storage, and most of the interactions showed a significant effect on the SCC variation. On average, the SCC was lower after freezing than in refrigeration. This effect depended specifically on type of preservation and analytical temperature of milk. The SCC of milk unpreserved or preserved with bronopol or potassium dichromate, and analyzed at 40 degrees C, was not affected by freezing; however, use of azidiol as a preservative before freezing, and heating the milk to 60 degrees C following thawing resulted in significantly decreased SCC. Milk age had little quantitative influence on SCC of thawed milk. The type of thawing (rapid and slow) did not significantly influence SCC of milk analyzed at 40 degrees C. As a result, when using properly handled samples, the Fossomatic method could be used to enumerate SCC in samples frozen over the 60 d.

Fossomatic cell-counting on ewe milk: comparison with direct microscopy and study of variation factors

Using the Fossomatic method (FSCC) a total of 23,003 analytical SCC observations were carried out on 6400 aliquots taken from 80 individual ewe milk samples with the objective of studying the influence of 4 preservation procedures (without preservation, potassium dichromate, azidiol, and bronopol), 2 storage temperatures (ambient and refrigeration), 10 milk ages (3,6,12, and 24h, and 2,3,4,5,7, and 9d postcollection), and two analytical temperatures (40 and 60 degrees C). In addition, each sample was analyzed with direct microscopic method (DMSCC), using 3 different stainings for each sample: methylene blue (MB), May-Grünwald-Giemsa (MGG) and Pyronin Y-methyl green (PGM). This allowed DMSCC and FSCC (at 24 h of age) to be compared. The reference DMSCC from MB staining was a reliable method in ewe milk, though more specific stainings such as MGG and PMG slightly improve the residual standard deviation for repeated SCC. Between DMSCC and FSCC, the highest coefficients of correlation (0.972 to 0.996) corresponded to preserved and refrigerated milk, and the lowest (0.708 to 0.919) to unpreserved and ambient stored aliquots. Except for the unpreserved and ambient stored aliquots, SCC values were similar in all aliquots. Under FSCC, preservation, storage and analytical temperature, milk age, and most of the interactions showed a significant effect on SCC variation. In preserved samples, logSCC values ranged between 5.67 (bronopol) and 5.62 (azidiol). The higest values (5.72) were for unpreserved milk, which showed false overestimation of SCC due to bacterial proliferation. LogSCC was higher at 60 degrees C (5.68) than at 40 degrees C (5.65). The interaction between age, preservation and storage temperature showed no cell degeneration in properly handled samples over the 9 d of study.

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.

Solid-phase microextraction with on-fibre derivatisation applied to the analysis of volatile carbonyl compounds

We have used a fast, sensitive and efficient method for the analysis of volatile carbonyl compounds (saturated aliphatic and unsaturated aldehydes) based on solid-phase microextraction with on-fibre derivatisation. Pentafluorophenylhydrazine was absorbed onto a poly(dimethylsiloxane)/divinylbenzene-coated fibre and exposed to the vapours of aldehyde-containing matrices. The hydrazones formed on the fibre were desorbed into the gas chromatograph injection port and quantified by means of electron-capture detection with high sensitivity (10-90 fmol) and good reproducibility (RSD<10%). The method was applied to the headspace-sampling of volatile carbonyl compounds released during the thermally-induced degradation of sunflower oil.

High-resolution gas-chromatographic analysis of the secondary metabolites obtained by subcritical-fluid extraction from Colombian rue (Ruta graveolens L.)

Subcritical (CO(2)) extraction, carried out in a J&W Scientific High Pressure Soxhlet Extractor, was used to isolate secondary metabolites from leaves, flowers, stems and roots of Colombian rue (Ruta graveolens L.). The various extracts were analyzed by capillary chromatography, on an HP-5 (30 m) column, using nitrogen-phosphorus, flame ionization, and mass selective detection systems. Kováts indexes and mass spectra (electron impact, 70 eV) were employed for compound identification. The extracts from the various parts of rue studied had different compositions. The number of compounds detected at concentrations above 0.01% (w/w) in the extracts from leaves, flowers, stems and roots, was 78, 45, 25 and 24, respectively. 2-Nonanone (8.9%), 2-undecanone (13.4%), chalepensin (13.0%), and geijerene (19.3%) were the main constituents found in the extracts from rue leaves, flowers, stems and roots, respectively. Furanocoumarins, furoquinolines, hydrocarbons and benzodioxol derivatives were the main compound families found in all extracts, at total concentrations between 3.7 and 33.9%, depending on the part of the plant. The extraction method used has low environmental impact and produced solvent-free extracts in good yield with no pigments, waxes, resins, or high-molecular weight compounds which may interfere with the isolation and analysis of the alkaloids responsible for rue's biological activity, which were extracted in relatively high yield.

Comparison of extraction methods and detection systems in the gas chromatographic analysis of volatile carbonyl compounds

High-resolution gas chromatography (HRGC) with electron-capture detection (ECD), nitrogen-phosphorus detection (NPD), flame ionization detection (FID) or with mass spectrometry-selected ion monitoring (MS-SIM) was used in the analysis of volatile carbonyl compounds. Eighteen carbonyl compounds that are typically produced during lipid peroxidation were derivatized quantitatively with pentafluorophenylhydrazine (PFPH) at room temperature, to afford their corresponding water-insoluble hydrazones. These derivatives were extracted into non-polar phases by means of either liquid-liquid extraction (LLE) (hexane) or solid-phase extraction (SPE) on 3 ml C18 octadecyl-bonded phase cartridges. Detection limits of 10(-14) and 10(-12) mol/ml per aldehyde were achieved with the ECD and MS-SIM systems, respectively. The effects of extraction conditions on sensitivity and recovery were determined by performing parallel HRGC-ECD and HRGC-MS-SIM analyses of pentafluorophenylhydrazones of the eighteen compounds under study. Recoveries of 51.4-78.9 +/- 1.2-4.5 and 80.9-98.3 +/- 1.0-3.5% were obtained with LLE and SPE, respectively. The method was applied to the analysis of the volatile carbonyl compounds in various heated vegetable oils (corn, palm or sunflower) and to the analysis of volatile aldehydes in human urine.

A potassium channel toxin from the secretion of the sea anemone Bunodosoma granulifera. Isolation, amino acid sequence and biological activity

A peptide toxin affecting potassium channels was isolated from the sea anemone Bunodosoma granulifera. It facilitates acetylcholine release at avian neuromuscular junctions, competes with dendrotoxin I, a probe for voltage-dependent potassium channels, for binding to synaptosomal membranes of rat brain with a Ki of 0.7 nM and suppresses K+ currents in rat dorsal root ganglion neurones in culture. It represents a new structural type of potassium channel toxin with the sequence V1RCDWFKETA10CRHAKSLGNC20RTSQKYRANC30AKTLQCC37 (M(r) 4275, three disulfides).