Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 40
Filter
1.
Molecules ; 24(9)2019 Apr 28.
Article in English | MEDLINE | ID: mdl-31035428

ABSTRACT

Mulinum crassifolium Phil. (Apiaceae) is an endemic shrub from Chile commonly used as infusion in traditional medicine to treat diabetes, bronchial and intestinal disorders and stomach ailments, including ulcers. From the EtOAc extract of this plant, the new mulinane-type diterpenoids 3 and 5 were isolated along with three known diterpenoids. The gastroprotective effect of the infusion of the plant was assayed to support the traditional use and a fast HPLC analysis using high resolution techniques was performed to identify the bioactive constituents. The EtOAc extract and the edible infusion showed gastroprotective effect at 100 mg/kg in the HCl/EtOH induced gastric ulcer model in mice, reducing lesions by 33% and 74%, respectively. Finally, a metabolomic profiling based on UHPLC-ESI-MS/HRMS of the edible infusion was performed and thirty-five compounds were tentatively identified including quercetin, caffeic acid, apigenine glucoside, p-coumaric acid, chlorogenic acids, and caffeoylquinic acids, which have been associated previously with gastroprotective and antiulcer properties. This scientific evidence can support the contribution of polyphenols in the gastroprotective activity of the edible infusion of this plant, and can validate at least in part, its ethnopharmacological use.


Subject(s)
Apiaceae/chemistry , Chromatography, High Pressure Liquid , Diterpenes/chemistry , Diterpenes/pharmacology , Gastrointestinal Tract/drug effects , Mass Spectrometry , Plant Extracts/chemistry , Animals , Metabolome , Metabolomics , Mice , Molecular Structure
2.
Molecules ; 24(4)2019 Feb 14.
Article in English | MEDLINE | ID: mdl-30769848

ABSTRACT

Extracts of bled resin from Azorella compacta, of the Azorelloideae family from the Andes (>4000 m), were analyzed by gas chromatography-mass spectrometry. The mass spectra of the dominant compounds of the resin and its hydrogenation products were documented. The most abundant compounds were oxygenated diterpenoids, namely mulinadien-20-oic (Δ11,13 and Δ11,14) acids, azorell-13-en-20-oic acid, 13α,14ß-dihydroxymulin-11-en-20-oic acid, and azorellanol, with a group of azorellenes and mulinadienes. The mass spectra of the novel diterpenoid hydrocarbons with the azorellane and mulinane skeletons were also presented. This study documents the molecular diversity of these diterpenoid classes, and could be of great utility for future organic geochemical, environmental, archeological, pharmaceutical, and forensic chemistry studies.


Subject(s)
Apiaceae/chemistry , Diterpenes/chemistry , Altitude , Apiaceae/growth & development , Apiaceae/metabolism , Biomarkers/chemistry , Diterpenes/isolation & purification , Diterpenes/metabolism
3.
J Enzyme Inhib Med Chem ; 33(1): 936-944, 2018 Dec.
Article in English | MEDLINE | ID: mdl-29734888

ABSTRACT

UHPLC/ESI/MS identification of organic compounds is the first step in the majority of screening techniques for the characterization of biologically active metabolites in natural sources. This paper describes a method for the fast identification and characterisation of secondary metabolites in Leptocarpha rivularis DC. (Palo negro) extracts by HPLC/UV (DAD)-Mass Spectrometry (HPLC/MS). The plant is used for the treatment of several diseases since pre-hispanic Mapuche times. Thirty-seven compounds were detected in the aqueous edible extract for the first time including 4 sesquiterpenes, 10 flavonoids, 9 oxylipins, 2 organic acids, and 11 phenolic acids. In addition, phenolic content antioxidant and cholinesterase inhibitory activities were measured for the first time using the edible infusion. The total polyphenol content of the infusion was 230.76 ± 2.5 mmol GAE/kg dry weight, while the antioxidant activity was 176.51 ± 28.84; 195.28 ± 4.83; and 223.92 ± 2.95 mmol TE/kg dry weight, for the DPPH, ABTS, and FRAP assays, respectively. The cholinesterase inhibitory activity was 7.38 ± 0.03 and 5.74 ± 0.06 mmol GALAE/kg, for the inhibition of acetylcholinesterase AChE and BChE, respectively, showing that this plant is a candidate for the isolation of compounds that can be useful for the treatment of neurodegenerative diseases. Furthermore, this plant could serve also as a raw material for the production of dietary supplements, due to its content of polyphenolic compounds.


Subject(s)
Antioxidants/pharmacology , Asteraceae/chemistry , Biological Products/pharmacology , Biphenyl Compounds/antagonists & inhibitors , Cholinesterase Inhibitors/pharmacology , Picrates/antagonists & inhibitors , Acetylcholinesterase/metabolism , Antioxidants/chemistry , Antioxidants/isolation & purification , Biological Products/chemistry , Biological Products/isolation & purification , Butyrylcholinesterase/metabolism , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/isolation & purification , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Flavonoids/chemistry , Flavonoids/isolation & purification , Flavonoids/pharmacology , Hydroxybenzoates/chemistry , Hydroxybenzoates/isolation & purification , Hydroxybenzoates/pharmacology , Molecular Structure , Oxylipins/chemistry , Oxylipins/isolation & purification , Oxylipins/pharmacology , Sesquiterpenes/chemistry , Sesquiterpenes/isolation & purification , Sesquiterpenes/pharmacology , Spectrometry, Mass, Electrospray Ionization , Structure-Activity Relationship
4.
Molecules ; 23(9)2018 Sep 15.
Article in English | MEDLINE | ID: mdl-30223578

ABSTRACT

Forty-three metabolites including several methoxylated flavonoids, tremetones, and ent-clerodane diterpenes were accurately identified for the first time in the ethanolic extract of P. quadrangularis by means of hyphenated UHPLC-quadrupole Orbitrap mass spectrometry, and seven isolated compounds were tested regarding gastroprotective activity using the HCl/EtOH-induced lesion model in mice. A new tremetone (compound 6) is reported based on spectroscopic evidence. The isolated clerodanes and tremetones showed gastroprotective activity in a mouse model, evidenced by compound 7 (p-coumaroyloxytremetone), which showed the highest gastroprotective activity (76%), which was higher than the control drug lansoprazole (72%). Our findings revealed that several constituents of this plant have gastroprotective activity, and particularly, p-coumaroyloxytremetone could be considered as a lead molecule to explore new gastroprotective agents. This plant is a rich source of biologically active tremetones and terpenoids which can support the ethnobotanical use of the plant.


Subject(s)
Anti-Ulcer Agents/administration & dosage , Asteraceae/chemistry , Benzofurans/administration & dosage , Diterpenes, Clerodane/administration & dosage , Stomach Ulcer/drug therapy , Animals , Anti-Ulcer Agents/chemistry , Anti-Ulcer Agents/pharmacology , Benzofurans/chemistry , Benzofurans/pharmacology , Disease Models, Animal , Diterpenes, Clerodane/chemistry , Diterpenes, Clerodane/pharmacology , Ethanol/adverse effects , Hydrochloric Acid/adverse effects , Lansoprazole/administration & dosage , Lansoprazole/therapeutic use , Mice , Molecular Structure , Plant Extracts/chemistry , Stomach Ulcer/chemically induced
5.
Molecules ; 22(11)2017 Oct 30.
Article in English | MEDLINE | ID: mdl-29084151

ABSTRACT

Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria. Lichens belonging to the Parmeliaceae family comprise 2700 species of lichens, including the Parmotrema genus which is composed of 300 species. The metabolites of this genus include depsides, depsidones, phenolics, polysaccharides, lipids, diphenylethers and dibenzofurans, which are responsible for the biological activities reported including antidiabetic, antihelmintic, anticancer, antioxidant, antibacterial, anti-inflammatory, antimitotic, antitumoral, antifungal, and antioxidant enzyme inhibitory. Due to scarce knowledge of metabolomic profiles of Parmotrema species (P. andinum and P. robustum), a full metabolome study based on ultra-high performance liquid chromatography- diode array detector-electrospray ionization-quadrupole-orbitrap-mass-spectrometry (UHPLC-DAD-ESI-Q-orbitrap MS) was performed for a comprehensive characterization of their substances. From the methanolic extracts of these species, a total of 54 metabolites were identified for the first time using this hyphenated technique, including thirty compounds in P. andinum, and thirty-seven in P. robustum. Moreover, two compounds were not identified as known compounds, and could be new structures, according to our data. This report shows that this technique is effective and accurate for rapid chemical identification of lichen substances and the compounds identified could serve as chemotaxonomic markers to differentiate these ruffle lichens.


Subject(s)
Metabolomics/methods , Methanol/chemistry , Parmeliaceae/chemistry , Chromatography, High Pressure Liquid , Molecular Structure , Spectrometry, Mass, Electrospray Ionization , Tandem Mass Spectrometry
6.
Bioorg Med Chem Lett ; 26(14): 3220-3222, 2016 07 15.
Article in English | MEDLINE | ID: mdl-27262597

ABSTRACT

Mulinane diterpenoids isolated from Azorella species have displayed gastroprotective effects in animal models. In this study we have transformed the main constituent, mulin-11,13-dien-20 oic acid from this plant using the filamentous fungus Mucor plumbeus and a ß-cyclodextrin inclusion complex and we have obtained two main products with good yields (33% and 15% for compound 4 and 5, respectively) for further preparation of semisynthetic derivatives to evaluate their gastroprotective effects. In addition, one of the compounds isolated from Azorella cuatrecasasii was new (9-epi-13α-hydroxymulinene 1). Six new derivatives 4a-4c and 5a-5c were then prepared by simple chemical transformations. The structures of all compounds were elucidated by spectroscopic means based on 1D and 2D-NMR techniques. Some 8 diterpenes were evaluated for their gastroprotective effects in the ethanol/HCl-induced ulcer model in mice at 20mg/kg. The highest gastroprotective activity was shown by 7α,16-dihydroxymulin-11,13-dien-20-oic acid 5, which was higher than the reference drug lansoprazole, while 16-hydroxymulin-11,13-dien-20-oic acid 4 was as active as lansoprazole.


Subject(s)
Anti-Ulcer Agents/pharmacology , Apiaceae/chemistry , Diterpenes/pharmacology , Gastric Mucosa/drug effects , Stomach Ulcer/drug therapy , beta-Cyclodextrins/pharmacology , Alcohols , Animals , Anti-Ulcer Agents/chemistry , Anti-Ulcer Agents/isolation & purification , Disease Models, Animal , Diterpenes/chemistry , Diterpenes/isolation & purification , Dose-Response Relationship, Drug , Gastric Mucosa/pathology , Hydrochloric Acid , Mice , Molecular Conformation , Stomach Ulcer/chemically induced , Stomach Ulcer/pathology , Structure-Activity Relationship , beta-Cyclodextrins/chemistry
7.
Bioorg Med Chem Lett ; 26(23): 5732-5735, 2016 12 01.
Article in English | MEDLINE | ID: mdl-27810240

ABSTRACT

Natural or synthetic coumarins showed gastroprotective and antiulcer activity in animal models. In this study, we have synthetized twenty coumarins using classic methods to evaluate their gastroprotective effects on the ethanol/HCl-induced gastric lesion model in mice at 20mg/kg. Among the coumarins synthetized, compounds 6 and 10 showed the greatest gastroprotective activity being as active as lansoprazole at 20mg/kg and reducing gastric lesions by 75 and 76%, respectively. Then, in a second experiment, compounds 6 and 10 were re-evaluated in order to understand the possible mode of gastroprotective activity. Regarding coumarin 6, the protective effect was reduced by pre-treatment of the mice with N-ethylmaleimide and l-NAME suggesting that sulfhydryl compounds and endogenous nitric oxide are involved in its gastroprotective activity. While for coumarin 10 the effect was reduced by pre-treatment with indomethacin suggesting that prostaglandins are positively involved in its gastroprotective activity.


Subject(s)
Anti-Ulcer Agents/chemistry , Anti-Ulcer Agents/therapeutic use , Coumarins/chemistry , Coumarins/therapeutic use , Prostaglandins/metabolism , Stomach Ulcer/drug therapy , TRPV Cation Channels/metabolism , Animals , Anti-Ulcer Agents/pharmacology , Coumarins/pharmacology , Gastric Mucosa/drug effects , Gastric Mucosa/metabolism , Mice , Nitric Oxide/metabolism , Stomach Ulcer/metabolism , Sulfhydryl Compounds/metabolism
8.
Molecules ; 21(3): 245, 2016 Feb 23.
Article in English | MEDLINE | ID: mdl-26907248

ABSTRACT

Mass spectrometry has become a method of choice to characterize bioactive compounds in biological samples because of its sensitivity and selectivity. Hybrid ultra-HPLC hyphenated with Orbitrap mass analyzer is an innovative state of the art technology that allows fast and accurate metabolomic analyses. In this work the metabolites of a Chilean mistletoe endemic to the VIII region of Chile were investigated for the first time using UHPLC mass analysis (UHPLC-PDA-HESI-Orbitrap MS(n)). The anthocyanins, together with the non-pigmented phenolics were fingerprinted and correlated with the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics, flavonoids and anthocyanins measured by spectroscopic methods. Six anthocyanins were identified, and among them, the 3-O-glycosides of delphinidin and cyanidin were the major ones. In addition, several phenolic acids (including feruloylquinic acid, feruloyl glucose, chlorogenic acid) and several flavonols (luteolin, quercetin, apigenin, isorhamnetin and glycoside derivatives) were also identified. The mistletoe leaves showed the highest antioxidant activity as measured by the DPPH radical bleaching, ferric reducing antioxidant power and superoxide anion scavenging activity tests (13.38 ± 0.47 µg/mL, 125.32 ± 5.96 µmolTE/g DW and 84.06 ± 4.59 at 100 µg/mL, respectively).


Subject(s)
Anthocyanins/chemistry , Antioxidants/chemistry , Flavonoids/chemistry , Flavonols/chemistry , Hydroxybenzoates/chemistry , Mistletoe/chemistry , Anthocyanins/isolation & purification , Antioxidants/isolation & purification , Biphenyl Compounds/antagonists & inhibitors , Chile , Chromatography, High Pressure Liquid/methods , Flavonoids/isolation & purification , Flavonols/isolation & purification , Hydroxybenzoates/isolation & purification , Picrates/antagonists & inhibitors , Plant Extracts/chemistry , Plant Leaves/chemistry , Tandem Mass Spectrometry/methods
9.
Molecules ; 21(1): 92, 2016 Jan 15.
Article in English | MEDLINE | ID: mdl-26784158

ABSTRACT

A small Chilean variety of pears growing in the town of Toconao, an oasis located at the northeastern edge of the Salar de Atacama, northern Chile, was studied by means of modern PDA and high resolution mass spectral data (UHPLC-PDA-HESI-orbitrap-MS/MS). In addition, the antioxidant features of the fruits were compared with the varieties Packhman's Triumph and Abate Fetel and correlated with the presence of phenolic compounds. The non-pigmented phenolics were fingerprinted and related to the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics and flavonoids measured by spectroscopic methods. The machine allowed a fast separation of 15 min employing a flow rate of 1 mL per minute and could accurately identify 25 compounds, including several isorhamnetin derivatives and phenolic acids, present in the peel and pulps of this Chilean variety for the first time. The compounds were monitored using a wavelength range of 210-800 nm. The native small Chilean pear showed the highest antioxidant activity measured as the bleaching of the DPPH radical, the ferric reducing antioxidant power and superoxide anion scavenging activity (8.61 ± 0.65 µg/mL, 712.63 ± 12.12 micromols trolox equivalents (µmol/TE)/100 g FW, and 82.89% ± 2.52% at 100 µg/mL, respectively).


Subject(s)
Antioxidants/isolation & purification , Flavonoids/isolation & purification , Fruit/chemistry , Phenols/isolation & purification , Pyrus/chemistry , Quercetin/analogs & derivatives , Antioxidants/chemistry , Antioxidants/metabolism , Biphenyl Compounds/antagonists & inhibitors , Biphenyl Compounds/chemistry , Chile , Chromatography, High Pressure Liquid/instrumentation , Chromatography, High Pressure Liquid/methods , Desert Climate , Flavonoids/biosynthesis , Flavonoids/chemistry , Phenols/chemistry , Phenols/metabolism , Picrates/antagonists & inhibitors , Picrates/chemistry , Plant Extracts/chemistry , Pyrus/metabolism , Quercetin/biosynthesis , Quercetin/chemistry , Quercetin/isolation & purification , Superoxides/antagonists & inhibitors , Superoxides/chemistry , Tandem Mass Spectrometry/instrumentation , Tandem Mass Spectrometry/methods
10.
Bioorg Med Chem Lett ; 25(14): 2813-7, 2015 Jul 15.
Article in English | MEDLINE | ID: mdl-26009162

ABSTRACT

Seventeen compounds (2-18) synthetized from the diterpenoid ent-beyer-15-en-18-ol (1) isolated from aerial part of Baccharis tola were tested for their gastroprotective activity on the model of HCl/EtOH-induced gastric lesions in mice. Furthermore cytotoxicity test toward fibroblasts and AGS cells were performed. The results showed that compound 1 (ED50=50 mg/kg), 2, 6 and 13 were the most active regarding gastroprotective activity. Compounds 8-10 and 17-18 showed the lowest cytotoxicity toward fibroblasts and AGS cells. Regarding to mode of gastroprotective action, the effect elicited by 6 (50 mg/kg) was reversed by Indomethacin but not by N-ethylmaleimide, N(G)-nitro-L-arginine methyl ester or ruthenium red, which suggests that prostaglandins are involved in the mode of gastroprotective action of 6.


Subject(s)
Abietanes/chemistry , Anti-Ulcer Agents/chemistry , Gastric Juice/metabolism , Prostaglandins/pharmacology , Sulfhydryl Compounds/pharmacology , Abietanes/isolation & purification , Abietanes/pharmacology , Animals , Anti-Ulcer Agents/isolation & purification , Anti-Ulcer Agents/pharmacology , Baccharis/chemistry , Baccharis/metabolism , Cell Line , Cell Survival/drug effects , Gastric Mucosa/drug effects , Gastric Mucosa/metabolism , Humans , Indomethacin/pharmacology , Mice , Plant Components, Aerial/chemistry , Plant Components, Aerial/metabolism , Plant Extracts/chemistry , Plant Extracts/pharmacology , Stomach Ulcer/chemically induced , Stomach Ulcer/drug therapy
11.
Mar Drugs ; 13(4): 1726-38, 2015 Mar 30.
Article in English | MEDLINE | ID: mdl-25830679

ABSTRACT

Ten known meroterpenoids and the new meroterpenoid 7 were isolated from the Chilean seaweed Stypopodium flabelliforme as their acetylated derivatives. Furthermore, the known metabolite taondiol has been isolated for the first time from this species. The molecular structure of the new metabolite was determined by spectroscopic methods based on 1D- and 2D-NMR. Isolation of 7 represents a key step toward a better understanding of the biogenesis of this class of meroterpenoids. Among the meroditerpenoids isolated, stypodiol, isoepitaondiol, epitaondiol and sargaol exhibited gastroprotective activity on the HCl/Ethanol-induced gastric lesions model in mice. Regarding the mode of gastroprotective action, the activity of epitaondiol was reversed significantly when animals were pretreated with indomethacin, N-ethylmaleimide and N-nitro-l-arginine methyl ester (L-NAME) suggesting that prostaglandins, sulfhydryl groups and nitric oxide are involved in their mode of gastroprotective action. In the case of sargaol the gastroprotective activity was attenuated with indomethacin and N-ethylmaleimide, which suggests that prostaglandins and sulfhydryl groups are also involved in the mode of action using this model.


Subject(s)
Anti-Ulcer Agents/isolation & purification , Disease Models, Animal , Diterpenes/isolation & purification , Drug Discovery , Phaeophyceae/chemistry , Seaweed/chemistry , Stomach Ulcer/prevention & control , Acetylation , Animals , Anti-Ulcer Agents/adverse effects , Anti-Ulcer Agents/chemistry , Anti-Ulcer Agents/therapeutic use , Cell Line , Chile , Diterpenes/adverse effects , Diterpenes/chemistry , Diterpenes/therapeutic use , Gastric Mucosa/drug effects , Humans , Mice , Molecular Structure , Pacific Ocean , Phaeophyceae/growth & development , Polynesia , Protective Agents/adverse effects , Protective Agents/chemistry , Protective Agents/isolation & purification , Protective Agents/therapeutic use , Random Allocation , Seaweed/growth & development , Stereoisomerism , Terpenes/adverse effects , Terpenes/chemistry , Terpenes/isolation & purification , Terpenes/therapeutic use
12.
Molecules ; 20(6): 11490-507, 2015 Jun 22.
Article in English | MEDLINE | ID: mdl-26111178

ABSTRACT

The antioxidant features, polyphenolic composition and chromatographic fingerprints of the aerial parts from three Chilean endemic plants from the Paposo Valley located on the cost of the Atacama Desert were investigated for the first time using high pressure liquid chromatography coupled with photodiode array detector and electrospray ionization mass analysis (HPLC-PDA-ESI-MS) and spectroscopic methods. The phenolic fingerprints obtained for the plants were compared and correlated with the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP) and quantification of the total content of phenolics and flavonoids measured by spectroscopic methods. Thirty phenolics were identified for the first time for these species, mostly phenolic acids, flavanones, flavonols and some of their glycoside derivatives, together with three saturated fatty acids (stearic, palmitic and arachidic acids). Nolana ramosissima showed the highest antioxidant activity (26.35 ± 1.02 µg/mL, 116.07 ± 3.42 µM Trolox equivalents/g dry weight and 81.23% ± 3.77% of inhibition in the DPPH, FRAP and scavenging activity (SA) assays, respectively), followed by  N. aplocaryoides (85.19 ± 1.64 µg/mL, 65.87 ± 2.33 µM TE/g DW and 53.27% ± 3.07%) and N. leptophylla (124.71 ± 3.01, 44.23 ± 5.18 µM TE/g DW and 38.63% ± 1.85%).


Subject(s)
Antioxidants/chemistry , Flavonoids/chemistry , Phenols/chemistry , Plant Extracts/chemistry , Solanaceae/chemistry , Antioxidants/isolation & purification , Chile , Chromatography, High Pressure Liquid , Flavonoids/isolation & purification , Fruit/chemistry , Hydroxybenzoates/chemistry , Hydroxybenzoates/isolation & purification , Mass Spectrometry , Phenols/isolation & purification
13.
Org Biomol Chem ; 12(33): 6406-13, 2014 Sep 07.
Article in English | MEDLINE | ID: mdl-25008488

ABSTRACT

Four new mulinane-type diterpenoids besides the known compounds mulin-11,13-dien-20-oic acid, 13α-hydroxyazorellane, 13ß-hydroxyazorellane, mulinolic acid, azorellanol, and mulin-11,13-dien-18-acetoxy-16,20-dioic acid were isolated from the Chilean plant Azorella trifurcata. One of the new metabolites isolated, 7α-acetoxy-9-epi-13ß-hydroxymulinane, possesses a new trans-syn-trans arrangement in a tricyclic ring system not previously encountered in nature. Among the mulinane diterpenoids isolated, mulin-11,13-dien-20-oic acid showed the gastroprotective effect on HCl-EtOH-induced gastric lesions in mice (ED50 = 55 mg kg(-1)). Regarding the mode of gastroprotective action for this active compound, its effect was reduced by pre-treatment of the mice with indomethacin and N-ethylmaleimide, suggesting that prostaglandins and sulfhydryl compounds are positively involved in the gastroprotective activity using this model.


Subject(s)
Apiaceae/chemistry , Diterpenes/therapeutic use , Gastritis/drug therapy , Plant Extracts/therapeutic use , Animals , Diterpenes/chemistry , Diterpenes/isolation & purification , Ethanol/administration & dosage , Ethylmaleimide , Gastritis/chemically induced , Hydrochloric Acid/administration & dosage , Indomethacin , Mice , NG-Nitroarginine Methyl Ester , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Ruthenium Red
14.
Molecules ; 19(12): 19516-31, 2014 Nov 26.
Article in English | MEDLINE | ID: mdl-25432006

ABSTRACT

An enantioselective total synthesis of the natural amino acid (2S,4R,5R)-4,5-di-hydroxy-pipecolic acid starting from D-glucoheptono-1, 4-lactone is presented. The best sequence employed as a key step the intramolecular nucleophilic displacement by an amino function of a 6-O-p-toluene-sulphonyl derivative of a methyl D-arabino-hexonate and involved only 12 steps with an overall yield of 19%. The structures of the compounds synthesized were elucidated on the basis of comprehensive spectroscopic (NMR and MS) and computational analysis.


Subject(s)
Amino Acids, Cyclic/chemistry , Amino Acids, Cyclic/chemical synthesis , Chemistry, Organic/methods , Pipecolic Acids/chemistry , Azides/chemistry , Catalysis , Models, Molecular , Piperidines/chemical synthesis , Piperidines/chemistry , Quantum Theory , Thermodynamics
15.
Molecules ; 19(11): 17400-21, 2014 Oct 29.
Article in English | MEDLINE | ID: mdl-25356563

ABSTRACT

Peels and edible pulp from three species of citrus including Citrus aurantifolia (varieties pica and sutil) and Citrus x lemon var. Genova widely cultivated and consumed in Northern Chile (I and II region) were analyzed for phenolic compounds and antioxidant activity for the first time. A high performance electrospray ionization mass spectrometry (HPLC-UV-ESI-MS) method was developed for the rapid identification of phenolics in extracts from peels and juices of all species. Several flavonoids including one kaempferol-O-hexoside (peak 16) and one hesperidin derivative (peak 22) three quercetin derivatives (peaks 4, 19 and 36), five isorhamnetin derivatives (peaks 5, 23, 24, 26 and 29) four luteolin derivatives (peaks 14, 25, 27 and 40), seven apigenin derivatives (peaks 2, 3, 12, 20, 34, 35 and 39), seven diosmetin derivatives (peaks 7-9, 17, 21, 31 and 37), three chrysoeriol derivatives (peaks 10, 18 and 30), and four eryodictiol derivatives (peaks 6, 13, 15 and 38) were identified in negative and positive mode using full scan mass measurements and MSn fragmentations. Ascorbic acid content was higher in the pulps of the varieties Genova and Sutil (60.13 ± 1.28 and 56.53 ± 1.06 mg ascorbic acid per g dry weight, respectively) while total phenolic content was higher in Pica peels followed by Sutil peels (34.59 ± 0.81 and 25.58 ± 1.02 mg/g GAE dry weight, respectively). The antioxidant capacity was also higher for Pica peels (10.34 ± 1.23 µg/mL in the DPPH assay and 120.63 ± 2.45 µM trolox equivalents/g dry weight in the FRAP assay). The antioxidant features together with the high polyphenolic contents can support at least in part, the usage of the peel extracts as nutraceutical supplements, especially to be used as anti-ageing products.


Subject(s)
Antioxidants/chemistry , Citrus/chemistry , Fruit/chemistry , Phenols/chemistry , Chile , Chromatography, High Pressure Liquid/methods , Flavonoids/chemistry , Mass Spectrometry/methods , Spectrophotometry, Ultraviolet/methods
16.
Molecules ; 19(8): 10936-55, 2014 Jul 28.
Article in English | MEDLINE | ID: mdl-25072199

ABSTRACT

The anthocyanin composition and HPLC fingerprints of six small berries endemic of the VIII region of Chile were investigated using high resolution mass analysis for the first time (HR-ToF-ESI-MS). The antioxidant features of the six endemic species were compared, including a variety of blueberries which is one of the most commercially significant berry crops in Chile. The anthocyanin fingerprints obtained for the fruits were compared and correlated with the antioxidant features measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics, flavonoids and anthocyanins measured by spectroscopic methods. Thirty one anthocyanins were identified, and the major ones were quantified by HPLC-DAD, mostly branched 3-O-glycosides of delphinidin, cyanidin, petunidin, peonidin and malvidin. Three phenolic acids (feruloylquinic acid, chlorogenic acid, and neochlorogenic acid) and five flavonols (hyperoside, isoquercitrin, quercetin, rutin, myricetin and isorhamnetin) were also identified. Calafate fruits showed the highest antioxidant activity (2.33 ± 0.21 µg/mL in the DPPH assay), followed by blueberry (3.32 ± 0.18 µg/mL), and arrayán (5.88 ± 0.21), respectively.


Subject(s)
Anthocyanins/chemistry , Antioxidants/chemistry , Antioxidants/pharmacology , Fruit/chemistry , Phenols/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plants, Edible/chemistry , Chile , Flavonols/chemistry , Free Radical Scavengers/chemistry , Free Radical Scavengers/pharmacology , Mass Spectrometry , Molecular Structure , Phenotype
17.
Eur J Mass Spectrom (Chichester) ; 30(2): 125-132, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38523368

ABSTRACT

Lichens are recognized by their unique compounds and diverse applications in food, medicines, and cosmetics. Using ultra-high pressure liquid chromatography, coupled with a high-resolution mass spectrometer, metabolomic profiling of the lichen Parmotrema perlatum, from a methanolic extract, was performed. Based on characteristic fragmentation patterns, twenty-five lichenic substances were tentatively identified including 5 depsides, 12 depsidones, 2 diphenyl ethers, 1 aromatic considered as possible artifact, 1 dibenzofuran, 1 carbohydrate, 1 organic acid, and 2 undefined compounds. To the best of our knowledge, this is a more complete report of their phytochemistry from P perlatum. Our findings of the P perlatum profile may contribute and complement the current data of the Parmotrema genus.


Subject(s)
Lactones , Lichens , Parmeliaceae , Lichens/chemistry , Spectrometry, Mass, Electrospray Ionization , Chile , Depsides , Chromatography, High Pressure Liquid/methods
18.
Plants (Basel) ; 13(11)2024 May 31.
Article in English | MEDLINE | ID: mdl-38891330

ABSTRACT

Membrane technology allows the separation of active compounds, providing an alternative to conventional methods such as column chromatography, liquid-liquid extraction, and solid-liquid extraction. The nanofiltration of a Muérdago (Tristerix tetrandus Mart.) fruit juice was realized to recover valuable metabolites using three different membranes (DL, NFW, and NDX (molecular weight cut-offs (MWCOs): 150~300, 300~500, and 500~700 Da, respectively)). The metabolites were identified by ESI-MS/MS. The results showed that the target compounds were effectively fractionated according to their different molecular weights (MWs). The tested membranes showed retention percentages (RPs) of up to 100% for several phenolics. However, lower RPs appeared in the case of coumaric acid (84.51 ± 6.43% (DL), 2.64 ± 2.21% (NFW), 51.95 ± 1.23% (NDX)) and some other phenolics. The RPs observed for the phenolics cryptochlorogenic acid and chlorogenic acid were 99.74 ± 0.21 and 99.91 ± 0.01% (DL membrane), 96.85 ± 0.83 and 99.20 ± 0.05% (NFW membrane), and 92.98 ± 2.34 and 98.65 ± 0.00% (NDX membrane), respectively. The phenolic quantification was realized by UHPLC-ESI-MS/MS. The DL membrane allowed the permeation of amino acids with the MW range of about 300~100 Da (aspartic acid, proline, tryptophan). This membrane allowed the highest permeate flux (22.10-27.73 L/m2h), followed by the membranes NDX (16.44-20.82 L/m2h) and NFW (12.40-14.45 L/m2h). Moreover, the DL membrane allowed the highest recovery of total compounds in the permeate during the concentration process (19.33%), followed by the membranes NFW (16.28%) and NDX (14.02%). Permeate fractions containing phenolics and amino acids were identified in the membrane permeates DL (10 metabolites identified), NFW (13 metabolites identified), and NDX (10 metabolites identified). Particularly, tryptophan was identified only in the DL permeate fractions obtained. Leucine and isoleucine were identified only in the NFW permeate fractions, whereas methionine and arginine were identified only in the NDX ones. Liquid permeates of great interest to the food and pharmaceutical industries were obtained from plant resources and are suitable for future process optimization and scale-up.

19.
Plants (Basel) ; 13(9)2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38732429

ABSTRACT

Alternative solvents are being tested as green solvents to replace the traditional organic solvents used in both academy and industry. Some of these are already available, such as ethyl lactate, cyrene, limonene, glycerol, and others. This alternative explores eco-friendly processes for extracting secondary metabolites from nature, thus increasing the number of unconventional extraction methods with lower environmental impact over conventional methods. In this context, the Peruvian Ambrosia arborescens was our model while exploring a microwave-assisted extraction (MAE) approach over maceration. The objective of this study was to perform a phytochemical study including UHPLC-ESI-MS/MS and the antioxidant activity of Ambrosia arborescens, using sustainable strategies by mixing both microwaves and ethyl lactate as a green solvent. The results showed that ethyl lactate/MAE (15.07%) achieved a higher extraction yield than methanol/maceration (12.6%). In the case of the isolation of psilostachyin, it was similar to ethyl lactate (0.44%) when compared to methanol (0.40%). Regarding UHPLC-ESI-MS/MS studies, the results were similar. Twenty-eight compounds were identified in the ethyl lactate/MAE and methanol/maceration extracts, except for the tentative identification of two additional amino acids (peaks 4 and 6) in the MeOH extract. In relation to the antioxidant assay, the activity of the ethyl lactate extract was a little higher than the methanol extract in terms of ORAC (715.38 ± 3.2) and DPPH (263.04 ± 2.8). This study on A. arborescens demonstrated that the unconventional techniques, such as MAE related to ethyl lactate, could replace maceration/MeOH for the extraction and isolation of metabolites from diverse sources. This finding showed the potential of unconventional methods with green solvents to provide eco-friendly methods based on green chemistry.

20.
Molecules ; 19(1): 438-58, 2013 Dec 31.
Article in English | MEDLINE | ID: mdl-24384924

ABSTRACT

Antioxidant capacities and polyphenolic contents of two mango cultivars from northern Chile, one of them endemic of an oasis in the Atacama Desert, were compared for the first time. Twenty one phenolic compounds were detected in peel and pulp of mango fruits varieties Pica and Tommy Atkins by HPLC-PDA-MS and tentatively characterized. Eighteen compounds were present in Pica pulp (ppu), 13 in Pica peel (ppe) 11 in Tommy Atkins pulp (tpu) and 12 in Tommy Atkins peel (tpe). Three procyanidin dimers (peaks 6, 9 and 10), seven acid derivatives (peaks 1-4, 11, 20 and 21) and four xanthones were identified, mainly mangiferin (peak 12) and mangiferin gallate, (peak 7), which were present in both peel and pulp of the two studied species from northern Chile. Homomangiferin (peak 13) was also present in both fruit pulps and dimethylmangiferin (peak 14) was present only in Tommy pulp. Pica fruits showed better antioxidant capacities and higher polyphenolic content (73.76/32.23 µg/mL in the DPPH assay and 32.49/72.01 mg GAE/100 g fresh material in the TPC assay, for edible pulp and peel, respectively) than Tommy Atkins fruits (127.22/46.39 µg/mL in the DPPH assay and 25.03/72.01 mg GAE/100 g fresh material in the TPC assay for pulp and peel, respectively). The peel of Pica mangoes showed also the highest content of phenolics (66.02 mg/100 g FW) measured by HPLC-PDA. The HPLC generated fingerprint can be used to authenticate Pica mango fruits and Pica mango food products.


Subject(s)
Antioxidants/chemistry , Chromatography, High Pressure Liquid , Mangifera/chemistry , Mass Spectrometry , Polyphenols/chemistry , Biflavonoids/chemistry , Catechin/chemistry , Chile , Flavonoids/chemistry , Fruit/chemistry , Phenols/chemistry , Plant Extracts/chemistry , Proanthocyanidins/chemistry , Tannins/chemistry , Xanthones/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL