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1.
Molecules ; 28(3)2023 Jan 25.
Article En | MEDLINE | ID: mdl-36770845

In this work, a new analytical approach is proposed for monitoring biogenic volatile organic compounds (BVOCs) by combining headspace bar adsorptive microextraction (HS-BAµE) with gas chromatography-mass spectrometry (GC-MS). The HS-BAµE methodology was developed, optimized, validated and applied for the analysis of BVOCs emitted from two tree species (Eucalyptus globulus Labill. and Pinus pinaster Aiton) and compared with headspace solid phase microextraction (HS-SPME), commonly accepted as a reference technique. To achieve optimum experimental conditions, numerous assays were carried out by both methodologies, studying the release of the five major monoterpenoids (α-pinene, ß-pinene, myrcene, limonene and 1,8-cineole) from the leaves of the tree species, whereas the maximum selectivity and efficiency were obtained using an activated carbon and PDMS/DVB fiber as sorbent phases for HS-BAµE and HS-SPME, respectively. Under optimized experimental conditions, both methodologies showed similar profiling and proportional responses, although the latter present a higher sensitivity in the analytical configuration used. For the five monoterpenoids studied, acceptable detection limits (LODs = 5.0 µg L-1) and suitable linear dynamic ranges (20.0-100.0 mg L-1; r2 ≥ 0.9959) were achieved, and intra- and inter-day studies proved that both methodologies exhibited good results (RSD and %RE ≤ 19.9%), which indicates a good fit for the assessment of BVOCs by the HS-BAµE/GC-MS methodology. Assays performed on sampled leaves by both optimized and validated methodologies showed high levels of the five major BVOCs released from E. globulus Labill. (10.2 ± 1.3 to 7828.0 ± 40.0 µg g-1) and P. pinaster Aiton (9.2 ± 1.4 to 3503.8 ± 396.3 µg g-1), which might act as potential fuel during forest fire's propagation, particularly under extreme atmospheric conditions. This is the first time that BAµE technology was applied in the HS sampling mode, and, in addition to other advantages, it has proven to be an effective and promising analytical alternative for monitoring VOCs, given its great simplicity, easy handling and low cost.


Trees , Volatile Organic Compounds , Adsorption , Solid Phase Microextraction/methods , Gas Chromatography-Mass Spectrometry , Eucalyptol
2.
Molecules ; 26(11)2021 May 22.
Article En | MEDLINE | ID: mdl-34067333

This work entailed the development, optimization, validation, and application of a novel analytical approach, using the bar adsorptive microextraction technique (BAµE), for the determination of the six most common tricyclic antidepressants (TCAs; amitriptyline, mianserin, trimipramine, imipramine, mirtazapine and dosulepin) in urine matrices. To achieve this goal, we employed, for the first time, new generation microextraction devices coated with convenient sorbent phases, polymers and novel activated carbons prepared from biomaterial waste, in combination with large-volume-injection gas chromatography-mass spectrometry operating in selected-ion monitoring mode (LVI-GC-MS(SIM)). Preliminary assays on sorbent coatings, showed that the polymeric phases present a much more effective performance, as the tested biosorbents exhibited low efficiency for application in microextraction techniques. By using BAµE coated with C18 polymer, under optimized experimental conditions, the detection limits achieved for the six TCAs ranged from 0.2 to 1.6 µg L-1 and, weighted linear regressions resulted in remarkable linearity (r2 > 0.9960) between 10.0 and 1000.0 µg L-1. The developed analytical methodology (BAµE(C18)/LVI-GC-MS(SIM)) provided suitable matrix effects (90.2-112.9%, RSD ≤ 13.9%), high recovery yields (92.3-111.5%, RSD ≤ 12.3%) and a remarkable overall process efficiency (ranging from 84.9% to 124.3%, RSD ≤ 13.9%). The developed and validated methodology was successfully applied for screening the six TCAs in real urine matrices. The proposed analytical methodology proved to be an eco-user-friendly approach to monitor trace levels of TCAs in complex urine matrices and an outstanding analytical alternative in comparison with other microextraction-based techniques.


Antidepressive Agents, Tricyclic/urine , Solid Phase Microextraction/methods , Urinalysis/methods , Adsorption , Biocompatible Materials/chemistry , Charcoal/chemistry , Gas Chromatography-Mass Spectrometry , Humans , Hydrogen-Ion Concentration , Ions , Limit of Detection , Liquid Phase Microextraction/methods , Polymers/chemistry , Polypropylenes/chemistry , Reproducibility of Results , Urinalysis/standards , Water/chemistry
3.
Molecules ; 26(8)2021 Apr 09.
Article En | MEDLINE | ID: mdl-33918766

The analysis of controlled drugs in forensic matrices, i.e., urine, blood, plasma, saliva, and hair, is one of the current hot topics in the clinical and toxicological context. The use of microextraction-based approaches has gained considerable notoriety, mainly due to the great simplicity, cost-benefit, and environmental sustainability. For this reason, the application of these innovative techniques has become more relevant than ever in programs for monitoring priority substances such as the main illicit drugs, e.g., opioids, stimulants, cannabinoids, hallucinogens, dissociative drugs, and related compounds. The present contribution aims to make a comprehensive review on the state-of-the art advantages and future trends on the application of microextraction-based techniques for screening-controlled drugs in the forensic context.


Forensic Medicine , Liquid Phase Microextraction/methods , Pharmaceutical Preparations/analysis , Solid Phase Microextraction/methods , Humans , Illicit Drugs/analysis
4.
Environ Sci Pollut Res Int ; 28(14): 17228-17243, 2021 Apr.
Article En | MEDLINE | ID: mdl-33394452

The increased use of pharmaceutical and personal care products (PPCPs) has contributed to the contamination of water systems and put pressure on the development of new techniques to deal with this problem. Acetaminophen (paracetamol), a common analgesic and antipyretic drug, and caffeine, a known central nervous system stimulant, are being used frequently by many people and found in large amounts in wastewater systems. In this work, their removal, by photocatalytic degradation, was promoted using magnetic nanoparticles (NPs) based on iron oxides. Besides being obtained from cheap and plentiful source, the magnetic properties of these NPs provide an easy way to separate them from the solution when the reaction is complete. Three types of hematite-based NPs, one pure (1) and two of them composed by a magnetite core partially (2) or completely (3) covered by a hematite shell, were synthesized and characterized. Sample 2 was the best photocatalyst for both pollutants' photo-assisted degradation. Under UV-vis irradiation and using a 0.13 g catalyst/L solution, the total acetaminophen and caffeine degradation (20 ppm/150 mL) was achieved in 45 min and 60 min, respectively. The identification of some of the intermediate products was carried out by liquid chromatography in combination with electrospray ionization mass spectrometry. A complementary Density Functional Theory (DFT) study revealed the relative stability of several species formed during the acetaminophen and caffeine degradation processes and gave some insight about the most favorable degradation pathways.


Magnetite Nanoparticles , Water Pollutants, Chemical , Acetaminophen , Caffeine , Catalysis , Ferric Compounds , Ferrosoferric Oxide , Humans , Kinetics , Titanium , Water Pollutants, Chemical/analysis
5.
Nat Prod Res ; 35(22): 4753-4756, 2021 Nov.
Article En | MEDLINE | ID: mdl-32013559

This work reports for the first time the in vitro anti-oxidant (towards DPPH, ABTS, copper and iron), enzymatic inhibitory (on AChE, BuChE, α-glucosidase, α-amylase and tyrosinase), cytotoxicity (towards HepG2 and HEK 293 cells), and metabolomics (by HPLC-MS) of extracts from organs of Malcolmia littorea (L.) R.Br. Extracts were constituted mainly by phenolic acids and flavonoids, and main compounds were salicylic acid and luteolin-7-O-glucoside. Samples showed reduced radical scavenging and metal chelating capacity, and only the methanol extracts reduced iron. The root's ethanol and methanol extracts, and the aerial organ's ethanol extract exhibited the highest AChE inhibition. The root's ethanol extract displayed dual anti-cholinesterase activity. Samples showed a low capacity to inhibit α-amylase, but a high α-glucosidase inhibition was obtained with the root's and flower's ethanol extracts, and flower's methanol extract. Overall, samples displayed a high inhibition against tyrosinase, reduced HepG2 cellular viability and were less toxic towards HEK 293 cells.


Antioxidants , Brassicaceae , Antioxidants/pharmacology , Enzyme Inhibitors/pharmacology , HEK293 Cells , Humans , Phytochemicals , Plant Extracts/pharmacology , Salt-Tolerant Plants
6.
ACS Appl Bio Mater ; 3(4): 2078-2091, 2020 Apr 20.
Article En | MEDLINE | ID: mdl-35025329

Thirteen carbon materials comprising commercial activated carbons and lab-made materials (activated carbons, hydrochars, and low-T and high-T activated hydrochars) were assayed as sorbent coatings in bar adsorptive microextration (BAµE) to monitor trace levels of ten common pharmaceutical compounds (PhCs) in environmental water matrices including surface water, seawater, tap water, and wastewater. Polar and nonpolar pharmaceuticals were selected, sulfamethoxazole, triclosan, carbamazepine, diclofenac, mefenamic acid, 17-α-ethinylestradiol, 17-ß-estradiol, estrone, gemfibrozil, and clofibric acid, as model compounds to cover distinct therapeutic classes. Despite having a less-developed porosity, data showed that "in-house" prepared low-T activated hydrochars, obtained from carbohydrates and an eutectic salt mixture at low temperature (i.e., 180 °C) and autogenerated pressure, compete with the best commercial activated carbons for this particular application. The combination of a micro and mesopore network with a rich oxygen-based surface chemistry yielding an acidic nature allowed these low-T activated hydrochars to present the best overall recoveries (between 20.9 and 82.4%) for the simultaneous determination of the ten target PhCs with very distinct chemical properties using high performance liquid chromatography-diode array detection (HPLC-DAD).

7.
Molecules ; 24(5)2019 Mar 07.
Article En | MEDLINE | ID: mdl-30866456

Multi-spheres adsorptive microextraction using powdered activated carbons (ACs) was studied as a novel enrichment approach, followed by liquid desorption and high-performance liquid chromatography with diode array detection (MSAµE(AC)-LD/HPLC-DAD) to monitor caffeine (CAF) and acetaminophen (ACF) traces in environmental matrices. In this study, commercial activated carbons (N, NOX, and R) were tested, with the latter showing a much better performance for the analysis of both anthropogenic drugs. The main parameters affecting the efficiency of the proposed methodology are fully discussed using commercial AC(R). Textural and surface chemistry properties of the ACs sample were correlated with the analytical results. Assays performed on 30 mL of water samples spiked at 10 µg L-1 under optimized experimental conditions, yielding recoveries of 75.3% for ACF and 82.6% for CAF. The methodology also showed excellent linear dynamic ranges for both drugs with determination coefficients higher than 0.9976, limits of detection and quantification of 0.8⁻1.2 µg L-1 and 2.8⁻4.0 µg L-1, respectively, and suitable precision (RSD < 13.8%). By using the standard addition method, the application of the present method to environmental matrices, including superficial, sea, and wastewater samples, allowed very good performance at the trace level. The proposed methodology proved to be a feasible alternative for polar compound analysis, showing to be easy to implement, reliable, and sensitive, with the possibility to reuse and store the analytical devices loaded with the target compounds for later analysis.


Acetaminophen/isolation & purification , Caffeine/isolation & purification , Solid Phase Microextraction/methods , Water/analysis , Adsorption , Charcoal/chemistry , Chromatography, High Pressure Liquid/methods , Limit of Detection , Water Pollutants, Chemical/isolation & purification
8.
Food Chem Toxicol ; 111: 525-536, 2018 Jan.
Article En | MEDLINE | ID: mdl-29217268

Bidens tripartita L. is a traditional phyto-remedy used in several countries, yet there is still a paucity of data on its biological potential. We aimed to provide new insights on the pharmacological potential of extracts prepared from B. tripartita via highlighting its antioxidant, key enzymes inhibitory potency, and DNA protecting effects. Phytochemical profile was established using High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) and bioactive compound(s) docked against target enzymes using in silico methods. Cytotoxicity against three cancer cell lines was assessed using the methylthiazolyldiphenyl-tetrazolium bromide (MTT) cell viability test. The main compounds were luteolin-7-glucoside (cynaroside), chlorogenic acid, and epicatechin in the extracts. The methanol extract exhibited the highest radical scavenging activity. Ethyl acetate extract showed strongest α-amylase inhibitory activity, while the best α-glucosidase inhibitory effect recorded for the methanol extract. Molecular docking showed that cynaroside strongly interact to α-glucosidase cavity by establishing six hydrogen bonds. B. tripartita extracts were found to protect supercoiled form of pUC19 plasmid (>70%) and also showed anti-proliferative properties. Results amassed in the present study add on to a growing body of literature on the multi-pharmacological potency of B. tripartita which can be applied to bio-products development geared towards management of common diseases.


Bidens/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Cell Line , Cell Survival/drug effects , Chromatography, High Pressure Liquid , Computer Simulation , Molecular Docking Simulation , alpha-Glucosidases/chemistry , alpha-Glucosidases/metabolism
9.
Pharm Biol ; 55(1): 1348-1357, 2017 Dec.
Article En | MEDLINE | ID: mdl-28301958

CONTEXT: Several Polygonum species (Polygonaceae) are used in traditional medicine in Asia, Europe and Africa to treat inflammation and diabetes. OBJECTIVE: Evaluate the in vitro antioxidant, anti-inflammatory and antidiabetic potential of methanol and dichloromethane extracts of leaves and roots of the halophyte Polygonum maritimum L. MATERIAL AND METHODS: Antioxidant activity was determined (up to 1 mg/mL) as radical-scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), copper (CCA) and iron (ICA) chelating activities and iron reducing power (FRAP). NO production was measured in lipopolysaccharide (LPS)-stimulated macrophages for 24 h at concentrations up to 100 µg/mL and antidiabetic potential was assessed by α-amylase and α-glucosidase inhibition (up to 10 mg/mL) assays. The phytochemical composition of the extracts was determined by gas chromatography-mass spectrometry (GC-MS). RESULTS: The methanol leaf extract had the highest activity against DPPH• (IC50 = 26 µg/mL) and ABTS+• (IC50 = 140 µg/mL), FRAP (IC50 = 48 µg/mL) and CCA (IC50 = 770 µg/mL). Only the dichloromethane leaf extract (LDCM) showed anti-inflammatory activity (IC50 = 48 µg/mL). The methanol root (IC50 = 19 µg/mL) and leaf (IC50 = 29 µg/mL) extracts strongly inhibited baker's yeast α-glucosidase, but LDCM had higher rat's α-glucosidase inhibition (IC50 = 2527 µg/mL) than acarbose (IC50 = 4638 µg/mL). GC-MS analysis identified ß-sitosterol, stigmasterol, 1-octacosanol and linolenic acid as possible molecules responsible for the observed bioactivities. CONCLUSIONS: Our findings suggest P. maritimum as a source of high-value health promoting commodities for alleviating symptoms associated with oxidative and inflammatory diseases, including diabetes.


Anti-Inflammatory Agents/pharmacology , Hypoglycemic Agents/pharmacology , Plant Extracts/pharmacology , Polygonum , Animals , Antioxidants/pharmacology , Cell Survival/drug effects , Cells, Cultured , Gas Chromatography-Mass Spectrometry , Mice , Phytochemicals/analysis , Polygonum/chemistry , Rats
10.
Biomed Pharmacother ; 87: 27-36, 2017 Mar.
Article En | MEDLINE | ID: mdl-28040595

In this study, Methanolic extracts of Euphorbia denticulata parts (flowers, leaf, stem, and mix of aerial parts) were assessed for a panoply of bioactivities. Inhibitory potential against key enzymes involved in diabetes (α-glucosidase and α-amylase), obesity (pancreatic lipase), neurodegenerative diseases (cholinesterases), and hyperpigmentation (tyrosinase) was evaluated. The antioxidant and antibacterial properties were also assessed. The total phenolic, flavonoid, and phytochemical profile were established using HPLC/DAD and molecular modelling studies on specific target compounds were performed in silico. The flower extract was found to be rich in phenolics and flavonoids, (60.11±1.40mgGAE/g and 42.04±0.16mgRE/g respectively), which tend to correlate with the high radical scavenging activity of this extract (120.34±3.33mgTE/g and 165.42±2.16mgTE/g for DPPH and ABTS respectively). Catechin, epicatechin, gallic acid, p-OH-Benzoic acid, rosmarinic acid, and epigallocatechin gallate, found in significant abundance in the extracts were assessed using molecular modelling with the aim to study their docking properties on a set of six enzymes used in this study. The extracts were moderately effective with MIC values ranging between 1.56 to 6.25mg/ml, but potent growth inhibitors of MRSA strains. Results amassed herein can be used as a stimulus for further studies geared towards the development of novel phyto-pharmaceuticals.


Euphorbia , Flavonoids/isolation & purification , Phenols/isolation & purification , Phytochemicals/isolation & purification , Plant Extracts/isolation & purification , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Antioxidants/chemistry , Antioxidants/isolation & purification , Antioxidants/pharmacology , Drug Compounding , Flavonoids/chemistry , Flavonoids/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/physiology , Molecular Docking Simulation/methods , Phenols/chemistry , Phenols/pharmacology , Phytochemicals/chemistry , Phytochemicals/pharmacology , Plant Components, Aerial , Plant Extracts/chemistry , Plant Extracts/pharmacology
11.
Food Chem ; 200: 322-9, 2016 Jun 01.
Article En | MEDLINE | ID: mdl-26830595

This work reports the in vitro antioxidant and anti-inflammatory activities and toxicity of infusions and decoctions of Limonium algarvense flowers, and green tea. The total contents in different phenolic groups and the quantification of individual phenolics by HPLC are also reported. L. algarvense and green tea had similar antioxidant properties, except for hydroxyl radical-scavenging activity, higher on green tea, and iron chelating potential, higher on L. algarvense. The later species also had the uppermost anti-inflammatory potential. Green tea decoction had the highest content of phenolic groups, but the infusion of L. algarvense had higher amounts of salicylic, gallic and coumaric acids. L. algarvense was not toxic, whereas green tea was toxic for S17 cells. Under our experimental conditions, infusions and decoctions of L. algarvense flowers had similar or higher antioxidant and anti-inflammatory properties than green tea, and thus, may be useful for alleviating symptoms associated with oxidative and inflammatory-related diseases.


Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Camellia sinensis , Plant Extracts/pharmacology , Plumbaginaceae , Animals , Artemia , Cells, Cultured , Flowers/chemistry , Hep G2 Cells , Humans , Mice , Phenols/analysis , Plant Extracts/toxicity , Plumbaginaceae/chemistry , Tea
12.
Molecules ; 19(7): 9369-79, 2014 Jul 03.
Article En | MEDLINE | ID: mdl-24995922

Bar adsorptive microextraction combined with liquid desorption followed by high performance liquid chromatography with diode array detection (BAµE-LD/HPLC-DAD) is proposed for the determination of trace levels of five phenol compounds (3-nitrophenol, 4-nitrophenol, bisphenol-A, 4-n-octylphenol and 4-n-nonylphenol) in surface water matrices. By using a polystyrene-divinylbenzene copolymer (PS-DVB) sorbent phase, high selectivity and efficiency is achieved even against polydimethylsiloxane through stir bar sorptive extraction. Assays performed by BAµE(PS-DVB)-LD/HPLC-DAD on 25 mL water samples spiked at the 10.0 µg/L levels yielded recoveries over 88.0%±5.7% for all five analytes, under optimized experimental conditions. The analytical performance showed good precision (RSD<15%), detection limits of 0.25 µg/L and linear dynamic ranges (1.0-25.0 µg/L) with determination coefficient higher than 0.9904. By using the standard addition method, the application of the present method to surface water matrices allowed very good performances at the trace level. The proposed methodology proved to be a suitable alternative to monitor phenol compounds in surface water matrices, showing to be easy to implement, reliable, sensitive and requiring a low sample volume.


Endocrine Disruptors/analysis , Phenols/analysis , Water Pollutants, Chemical/analysis , Adsorption , Chromatography, High Pressure Liquid , Limit of Detection , Solid Phase Microextraction
13.
Phytother Res ; 28(9): 1329-34, 2014 Sep.
Article En | MEDLINE | ID: mdl-24633846

Artemisia gorgonum (Asteraceae) is an endemic plant to the Cape Verde islands and plays an important role in traditional medicine. The chloroform extract of the plant aerial parts afforded six sesquiterpene lactones, two methoxylated flavonoids, two lignans, and one tetracyclic triterpene, which were isolated by chromatographic methods and their structure established by physical and spectroscopic techniques. The cytotoxic activity of the three major constituents, namely, arborescin, artemetin, and sesamin, was evaluated on neuroblastoma (SH-SY5Y), hepatocarcinoma (HepG2), and nontumoral bone marrow stromal (S17) cell lines. The application of different concentrations of the compounds significantly decreased tumor cells viability at different extents, especially at the highest concentrations tested. Arborescin is the most promising compound as it was able to reduce tumoral cell viability with an IC50 significantly lower (229-233 µM; p < 0.01) than that of S17 cells (445 µM). Arborescin and artemetin were less toxic to nontumoral cells than the antitumoral drug tested, etoposide. Our results indicate that arborescin has a significant cytotoxic activity in vitro, more pronounced on the cancer cell lines, confirming A. gorgonum as a source of potential antitumoral molecules.


Antineoplastic Agents, Phytogenic/pharmacology , Artemisia/chemistry , Dioxoles/pharmacology , Flavonoids/pharmacology , Lignans/pharmacology , Plant Extracts/pharmacology , Sesquiterpenes, Guaiane/pharmacology , Animals , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Line , Cell Line, Tumor , Dioxoles/isolation & purification , Flavonoids/isolation & purification , Humans , Lignans/isolation & purification , Mice , Plant Components, Aerial , Plant Extracts/chemistry , Sesquiterpenes, Guaiane/isolation & purification
14.
Food Chem ; 141(3): 2501-6, 2013 Dec 01.
Article En | MEDLINE | ID: mdl-23870987

We investigated the metabolic profile and biological activities of the essential oil and polar extracts of Lavandula pedunculata subsp. lusitanica (Chaytor) Franco collected in south Portugal. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that oxygen-containing monoterpenes was the principal group of compounds identified in the essential oil. Camphor (40.6%) and fenchone (38.0%) were found as the major constituents. High-performance liquid chromatography with diode array detection (HPLC-DAD) analysis allowed the identification of hydroxycinnamic acids (3-O-caffeoylquinic, 4-O-caffeoylquinic, 5-O-caffeoylquinic and rosmarinic acids) and flavones (luteolin and apigenin) in the polar extracts, with rosmarinic acid being the main compound in most of them. The bioactive compounds from L. pedunculata polar extracts were the most efficient free-radical scavengers, Fe(2+) chelators and inhibitors of malondialdehyde production, while the essential oil was the most active against acetylcholinesterase. Our results reveal that the subspecies of L. pedunculata studied is a potential source of active metabolites with a positive effect on human health.


Lavandula/chemistry , Oils, Volatile/chemistry , Plant Extracts/chemistry , Animals , Antioxidants/chemistry , Antioxidants/metabolism , Antioxidants/pharmacology , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/metabolism , Cholinesterase Inhibitors/pharmacology , Gas Chromatography-Mass Spectrometry , Lavandula/metabolism , Lipid Peroxidation/drug effects , Metabolome , Mice , Monoterpenes/chemistry , Monoterpenes/metabolism , Monoterpenes/pharmacology , Oils, Volatile/metabolism , Oils, Volatile/pharmacology , Plant Extracts/metabolism , Plant Extracts/pharmacology , Portugal
15.
J Sci Food Agric ; 93(11): 2707-14, 2013 Aug 30.
Article En | MEDLINE | ID: mdl-23553824

BACKGROUND: There is a growing interest in industry to replace synthetic chemicals by natural products with bioactive properties. Aromatic plants are excellent sources of bioactive compounds that can be extracted using several processes. As far as oregano is concerned, studies are lacking addressing the effect of extraction processes in bioactivity of extracts. This study aimed to characterise the in vitro antioxidant and antibacterial properties of oregano (Origanum vulgare) essential oil and extracts (in hot and cold water, and ethanol), and the chemical composition of its essential oil. RESULTS: The major components of oregano essential oil were carvacrol, ß-fenchyl alcohol, thymol, and γ-terpinene. Hot water extract had the strongest antioxidant properties and the highest phenolic content. All extracts were ineffective in inhibiting the growth of the seven tested bacteria. In contrast, the essential oil inhibited the growth of all bacteria, causing greater reductions on both Listeria strains (L. monocytogenes and L. innocua). CONCLUSION: O. vulgare extracts and essential oil from Portuguese origin are strong candidates to replace synthetic chemicals used by the industry.


Oils, Volatile/chemistry , Origanum/chemistry , Plant Extracts/chemistry , Plant Oils/chemistry , Antioxidants/chemistry
16.
Molecules ; 17(3): 3082-92, 2012 Mar 12.
Article En | MEDLINE | ID: mdl-22410418

Acetylcholinesterase inhibition, antioxidant and cytotoxic activities of Hedychium gardnerianum leaf essential oils from S. Miguel Island were determined. All the oils inhibited acetylcholinesterase, with IC(50) values of approximately 1 mg/mL, showing no statistical differences between collection sites. Three oils presented mixed inhibition, whilst one was almost truly competitive. This activity can be attributed to the presence of sesquiterpenes, which constituted more than 60% of the composition of the oils. Regarding the antioxidant activity as measured by the DPPH method, all the oils presented activities similar to reference compounds, although with statistical differences between collection sites. Cytotoxicity measured using Artemia salina classified these oils as moderately toxic, with LC(50) values ranging from 300 to 500 µg/mL. These results indicate a possible application of these oils in aromatherapy as coadjuvants in the treatment of cognitive diseases such as Alzheimer, since they may contribute to increase acetylcholine in cholinergic neurons and simultaneously fight deleterious oxidations responsible by neurological degeneration.


Cholinesterase Inhibitors/chemistry , Free Radical Scavengers/chemistry , Oils, Volatile/chemistry , Plant Oils/chemistry , Terpenes/chemistry , Zingiberaceae/chemistry , Acetylcholinesterase/chemistry , Animals , Artemia/drug effects , Biphenyl Compounds/chemistry , Cholinesterase Inhibitors/isolation & purification , Cholinesterase Inhibitors/pharmacology , Cytotoxins/chemistry , Cytotoxins/isolation & purification , Cytotoxins/pharmacology , Free Radical Scavengers/isolation & purification , Free Radical Scavengers/pharmacology , Kinetics , Lethal Dose 50 , Oils, Volatile/isolation & purification , Oils, Volatile/pharmacology , Picrates/chemistry , Plant Leaves/chemistry , Plant Oils/isolation & purification , Plant Oils/pharmacology , Terpenes/isolation & purification
17.
J Agric Food Chem ; 59(18): 10239-46, 2011 Sep 28.
Article En | MEDLINE | ID: mdl-21838232

Green coffee bean isotopes have been used to trace the effects of different climatic and geological characteristics associated with the Hawaii islands. Isotope ratio mass spectrometry (IRMS) and inductively coupled plasma mass spectrometry ((MC)-ICP-SFMS and ICP-QMS) were applied to determine the isotopic composition of carbon (δ13C), nitrogen (δ15N), sulfur (δ34S), and oxygen (δ18O), the isotope abundance of strontium (87Sr/86Sr), and the concentrations of 30 different elements in 47 green coffees. The coffees were produced in five Hawaii regions: Hawaii, Kauai, Maui, Molokai, and Oahu. Results indicate that coffee plant seed isotopes reflect interactions between the coffee plant and the local environment. Accordingly, the obtained analytical fingerprinting could be used to discriminate between the different Hawaii regions studied.


Coffea/classification , Coffea/growth & development , Environment , Isotopes/analysis , Seeds/classification , Carbon Isotopes/analysis , Hawaii , Nitrogen Isotopes/analysis , Oxygen Isotopes/analysis , Seeds/chemistry , Strontium Isotopes/analysis , Sulfur Isotopes/analysis
18.
J Agric Food Chem ; 57(24): 11557-63, 2009 Dec 23.
Article En | MEDLINE | ID: mdl-19928761

Winter savory Satureja montana is a medicinal herb used in traditional gastronomy for seasoning meats and salads. This study reports a comparison between conventional (hydrodistillation, HD, and Soxhlet extraction, SE) and alternative (supercritical fluid extraction, SFE) extraction methods to assess the best option to obtain bioactive compounds. Two different types of extracts were tested, the volatile (SFE-90 bar, second separator vs HD) and the nonvolatile fractions (SFE-250 bar, first and second separator vs SE). The inhibitory activity over acetyl- and butyrylcholinesterase by S. montana extracts was assessed as a potential indicator for the control of Alzheimer's disease. The supercritical nonvolatile fractions, which showed the highest content of (+)-catechin, chlorogenic, vanillic, and protocatechuic acids, also inhibited selectively and significantly butyrylcholinesterase, whereas the nonvolatile conventional extract did not affect this enzyme. Microbial susceptibility tests revealed the great potential of S. montana volatile supercritical fluid extract for the growth control and inactivation of Bacillus subtilis and Bacillus cereus, showing some activity against Botrytis spp. and Pyricularia oryzae. Although some studies were carried out on S. montana, the phytochemical analysis together with the biological properties, namely, the anticholinesterase and antimicrobial activities of the plant nonvolatile and volatile supercritical fluid extracts, are described herein for the first time.


Anti-Infective Agents/pharmacology , Chemical Fractionation/methods , Cholinesterase Inhibitors/pharmacology , Chromatography, Supercritical Fluid/methods , Plant Extracts/chemistry , Plant Extracts/pharmacology , Satureja/chemistry , Anti-Infective Agents/chemistry , Bacillus/drug effects , Cholinesterase Inhibitors/chemistry , Microbial Sensitivity Tests , Oils, Volatile/chemistry , Oils, Volatile/pharmacology , Phytotherapy , Plant Components, Aerial/chemistry , Plants, Medicinal/chemistry
19.
Nat Prod Res ; 23(3): 219-29, 2009.
Article En | MEDLINE | ID: mdl-19235022

The aim of this study was to evaluate the antimicrobial activity of Drosophyllum lusitanicum leaf extract against various yeasts and bacteria species, including both standard and clinically isolated strains. The extract exhibited strong antimicrobial activity against all the tested yeast strains with inhibition zones ranging 23.67-42.23 mm and with minimum inhibitory concentration (MIC) values ranging 31-63 microg L(-1). All the Gram-positive bacteria studied were inhibited by the extract, showing inhibition zones ranging 17.67-43.00 mm and MIC values comprising between 15.6 and 250 microg L(-1). In contrast, the growth of the tested Gram-negative bacteria was not significantly affected by the extract. Among the microorganisms tested, Staphylococcus epidermidis ATCC 12228 was the most sensitive, presenting the lowest MIC value (15.6 microg L(-1)), while Enterococcus faecalis ATCC 29212 was the most tolerant (250 microg L(-1)). The extract of D. lusitanicum was analysed by gas chromatography-mass spectrometry and the major constituent found was plumbagin.


Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Magnoliopsida/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Gas Chromatography-Mass Spectrometry , Microbial Sensitivity Tests , Naphthoquinones/chemistry , Naphthoquinones/pharmacology , Plant Leaves/chemistry , Yeasts/drug effects
20.
Bioresour Technol ; 100(5): 1720-6, 2009 Mar.
Article En | MEDLINE | ID: mdl-19006666

The removal of a widespread used drug (i.e., ibuprofen) from water was investigated using high valuable carbon adsorbents obtained from chemical and physical activation of a bioresource (cork) and a municipal waste (plastic). The waste-derived carbons outperformed the adsorption capacity of commercial carbonaceous adsorbents due to their adequate features for the removal of the targeted compound. Regarding the adsorption mechanism, the results obtained point out that ibuprofen retention is favored in activated carbons with basic surface properties. On the other hand, the textural features also play an important role; the presence of a transport pores network (i.e., mesopores) is crucial to ensure the accessibility to the inner porosity, and the microporosity must be large enough to accommodate the ibuprofen molecule. Specifically, adsorbents with a large fraction of ultramicropores (pore widths <0.7 nm) are not adequate to effectively remove ibuprofen.


Charcoal/chemistry , Ibuprofen/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Adsorption , Charcoal/analysis , Kinetics , Porosity , Refuse Disposal/methods , Surface Properties
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