ABSTRACT
A new alkaloid pyrroloquinolone A (1), along with fifteen known compounds 2-16 were isolated from the petroleum ether, EtOAc and n-BuOH extracts of the whole plant Atractylis cancellata L. Their structures were elucidated on the basis of extensive spectroscopic analysis including 1D- and 2D-NMR and HR-ESI-MS techniques. This is the first report of alkaloids in the genus Atractylis. Some of the isolated compounds and extracts were evaluated for their antioxidant potential (scavenging activity of DPPH and ABTS radicals, and reducing Fe+3 and Cu+2 power assays) and acetylcholinesterase and butyrylcholinesterase inhibitory activities. Compounds 8 and 11 showed good antioxidant capacity compared to ascorbic acid, BHA, and BHT used as standards, whereas compounds 1 and 2 exhibited good anticholinesterase activities compared to galantamine used as standard.
Subject(s)
Alkaloids , Antioxidants/pharmacology , Atractylis , Cholinesterase Inhibitors/pharmacology , Quinolones/pharmacology , Alkaloids/isolation & purification , Alkaloids/pharmacology , Antioxidants/isolation & purification , Atractylis/chemistry , Cholinesterase Inhibitors/isolation & purification , Molecular Structure , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Plant Extracts/pharmacology , Quinolones/isolation & purificationABSTRACT
The novel coronavirus outbreak (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents the actual greatest global public health crisis. The lack of efficacious drugs and vaccines against this viral infection created a challenge for scientific researchers in order to find effective solutions. One of the promising therapeutic approaches is the search for bioactive molecules with few side effects that display antiviral properties in natural sources like medicinal plants and vegetables. Several computational and experimental studies indicated that flavonoids especially flavonols and their derivatives constitute effective viral enzyme inhibitors and possess interesting antiviral activities. In this context, the present study reviews the efficacy of many dietary flavonols as potential antiviral drugs targeting the SARS-CoV-2 enzymes and proteins including Chymotrypsin-Like Protease (3CLpro), Papain Like protease (PLpro), Spike protein (S protein) and RNA-dependent RNA polymerase (RdRp), and also their ability to interact with the angiotensin-converting enzyme II (ACE2) receptor. The relationship between flavonol structures and their SARS-CoV-2 antiviral effects were discussed. On the other hand, the immunomodulatory, the anti-inflammatory and the antiviral effects of secondary metabolites from this class of flavonoids were reported. Also, their bioavailability limitations and toxicity were predicted.
Subject(s)
COVID-19 Drug Treatment , COVID-19 , Flavonols/pharmacology , SARS-CoV-2 , Angiotensin-Converting Enzyme 2/metabolism , Antiviral Agents/pharmacology , COVID-19/metabolism , Coronavirus 3C Proteases/metabolism , Coronavirus RNA-Dependent RNA Polymerase/metabolism , Drug Development , Humans , Phytochemicals/pharmacology , SARS-CoV-2/drug effects , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/metabolismABSTRACT
The present work describes the in vitro biological activities of the crude extracts (petroleum ether, ethyl acetate and n-butanol) prepared from the species Ephedra altissima Desf. The estimation of total phenolic, flavonoid and tannin contents were carried out using the Folin-Ciocalteu, trichloroaluminum and acidified vanillin methods, respectively. The evaluation of the in vitro antioxidant activities were performed by three different methods namely: scavenging of the free radical ABTS, permanganate reducing antioxidant capacity, and potentiometric assay. In addition, the antibacterial activity was assessed by the agar disk diffusion assay against seven bacterial strains. The results of the phytochemical screening revealed the presence of several types of secondary metabolites. The EtOAc extract exhibited the highest content of phenols (125.62 ± 1.51 & 956;g EGA mg-1 of extract). The greatest flavonoid and tannin contents were observed for n-BuOH extract (19.18 ± 0.39 µg EQ mg-1 of extract and 8.95 ± 1.70 & 956;g EC mg-1 of extract, respectively). Moreover, the EtOAc extract revealed potent antioxidant activity in all the tested methods. Furthermore, the aqueous extract from the species E. altissima showed a good ability to reduce iron III to iron II with a value of 0.68 ± 0.3 moL eq L-1 in potentiometric assay. All the crude extracts (PE, EtOAc and n-BuOH) displayed inhibition of bacterial growth against at least three strains with values of MIC ranging from 3.125 to 50 µg mL-1. Therefore, these results suggest that Ephedra altissima could be used as an important source of natural bioactive compounds with antioxidant and antibacterial properties.
Subject(s)
Anti-Bacterial Agents , Antioxidants , Phytochemicals , Ephedra/immunology , Ephedra/microbiology , Ephedra/chemistryABSTRACT
The new acylated indole alkaloid glucoside indole-3-carboxylic acid-(6'-O-caffeoyl)-ß-D-glucoside 1 has been isolated from the ethyl acetate (EtOAC) extract of Saccocalyx satureioides Coss. & Dur. (Lamiaceae) together with eight known secondary metabolites 2-9. Two indoles 2 and 3, five methylated flavone aglycones 4-8 and one monoterpene glucoside 9 were reported for the first time in the genus Saccocalyx. The structural elucidation of these compounds was accomplished by spectroscopic methods including 1 D (1H and 13C) and 2 D (COSY, HSQC and HMBC) NMR techniques, and mass spectrometry, and by comparison with literature data. Light petroleum, EtOAc, chloroform and n-butanol (n-BuOH) extracts of S. Satureioides were screened for their antioxidant activity using DPPH radical scavenging and ß-carotene bleaching methods. The antibacterial activity of these extracts indicates that n-BuOH and EtOAc extracts possess the strongest activity.
Subject(s)
Anti-Bacterial Agents/isolation & purification , Antioxidants/isolation & purification , Lamiaceae/chemistry , Plant Extracts/chemistry , 1-Butanol , Acetates , Alkaloids/isolation & purification , Alkaloids/pharmacology , Anti-Bacterial Agents/chemistry , Antioxidants/chemistry , Flavones , Indole Alkaloids/isolation & purification , Indoles , Plant Extracts/pharmacologyABSTRACT
From acetonic extract of the whole plant Euphorbia pterococca Brot. (Euphorbiaceae), four new cycloartane-type ester triterpenes named cycloartenyl-2'E,4'E-decadienoate (1), cycloartenyl-2'E,4'Z-decadienoate (2), 24-methylenecycloartanyl-2'E,4'Z-tetradecadienoate (3), and 24-oxo-29-norcycloartanyl-2'E,4'Z-hexadecadienoate (4) were obtained along with nine known tetracyclic triterpenes (5-13). Their structures were established mainly by extensive use of spectroscopic techniques, including 1D (1H and 13C) and 2D homo- and heteronuclear NMR experiments (COSY, HSQC, HMBC and NOESY), and mass spectrometry (HRESIMS), and by comparison with data reported in the literature. In addition, the new compounds 1-3 have been tested for cytotoxicity, trypanocidal effects and on enzymes involved in endocannabinoid degradation. While inactive in all assays up to 100⯵M, 1 showed selective inhibition of α/ß-hydrolase 12 with an IC50 of 11.6⯱â¯1.9⯵M.
Subject(s)
Euphorbia/chemistry , Triterpenes/isolation & purification , Animals , Cell Line, Tumor , Esters/isolation & purification , HEK293 Cells , Humans , Magnetic Resonance Spectroscopy , Mice , Molecular Structure , Monoacylglycerol Lipases/antagonists & inhibitors , Nuclear Magnetic Resonance, Biomolecular , Plant Components, Aerial/chemistry , Plant Extracts/chemistry , Plant Roots/chemistry , RAW 264.7 Cells , Rats , Swine , Trypanosoma cruzi/drug effectsABSTRACT
In this study, six known compounds 1-6 were isolated from the aerial parts of Silene arenarioides Desf. using different chromatographic methods. The structures of these compounds were identified as maltol glycoside (1), soyacerebroside I (2), chrysin (3), apigenin (4), quercetin (5) and stigmasterol glucoside (6). The compounds (1) and (2) are reported for the first time from this genus. The isolated compounds were determined using NMR techniques (1H NMR, 13C NMR, COSY, HSQC and HMBC) and mass spectroscopy (ESI-MS). The antibacterial and antioxidant activities of extracts and of compound (1) have been evaluated. The antioxidant activity was performed by DPPH radical scavenging method, which showed that methanol extract possesses a good antioxidant activity with value of IC50 = 8.064 ± 0.005 µg/mL.
Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/chemistry , Antioxidants/pharmacology , Glycosides/chemistry , Glycosides/pharmacology , Silene/chemistry , Apigenin/analysis , Apigenin/pharmacology , Drug Evaluation, Preclinical/methods , Flavonoids/analysis , Flavonoids/chemistry , Glucosides/analysis , Glucosides/pharmacology , Magnetic Resonance Spectroscopy , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/pharmacology , Quercetin/analysis , Quercetin/pharmacology , Spectrometry, Mass, Electrospray Ionization , Stigmasterol/analogs & derivatives , Stigmasterol/analysis , Stigmasterol/pharmacologyABSTRACT
In this study, the various extracts of aerial parts of Helianthemum sessiliflorum Pers. were examined in vitro for possible source of antioxidants and for antibacterial activity. The antioxidant activity was performed by DPPH radical scavenging method which showed that ethyl acetate extract possessed the best antioxidant potential (IC50 = 32.75 ± 2.07 µg/mL). The significant linear correlation was realised between the values of the total phenolic/flavonoid content and antioxidant activity of plant extracts. The ethyl acetate and n-butanol extracts showed moderate antibacterial activity. In addition, the phytochemical study of n-butanol extract afforded nine known phenolic compounds (1-9). This is the first report of six of them (1, 3, 5-8) in Cistaceae family. The structural identification of the isolated compounds was achieved using several spectroscopic methods.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Cistaceae/chemistry , Plant Components, Aerial/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Polyphenols/chemistry , Polyphenols/pharmacology , 1-Butanol , Acetates , Bacteria/drug effects , Biphenyl Compounds/chemistry , Flavonoids/isolation & purification , Flavonoids/pharmacology , Free Radical Scavengers/chemistry , Free Radical Scavengers/pharmacology , Microbial Sensitivity Tests , Phenols/isolation & purification , Phenols/pharmacology , Picrates/chemistry , SolventsABSTRACT
The phytochemical study of ethyl acetate and n-butanol extracts of Pteranthus dichotomus Forssk. led to the isolation and identification of 11 compounds, including three glycolipids 1-3, one lignan 4, three flavonoids 5-7 and four phytosterols 8-11. Structures of the isolated compounds have been elucidated by analysis of 1D and 2D NMR data, and mass spectrometry EI-MS and ESI-MS and by comparison with literature data. Furthermore, the ethyl acetate and n-butanol extracts were examined for their antioxidant and antibacterial activities. The results showed that both extracts (PDAC and PDBU) had a moderate antioxidant activity (IC50 = 375.514 µg/mL and 691.333 µg/mL) respectively.
Subject(s)
Anti-Bacterial Agents/isolation & purification , Antioxidants/chemistry , Caryophyllaceae/chemistry , Flavonoids/chemistry , Phytosterols/chemistry , Plant Extracts/chemistry , Africa, Northern , Anti-Bacterial Agents/chemistry , Antioxidants/isolation & purification , Flavonoids/isolation & purification , Inhibitory Concentration 50 , Molecular Structure , Phytochemicals/chemistry , Phytochemicals/isolation & purification , Phytosterols/isolation & purificationABSTRACT
Three new anthranilic acid derivatives: N-(R)-3'-hydroxydocosanoylanthranilic acid (1), N-(R)-3'-hydroxytricosanoylanthranilic acid (2) and N-(R)-3'-hydroxytetracosanoylanthranilic acid (3), in addition to one knownanthranilic acid and six known flavonoids, were isolated from the ethyl acetate extract of Ononis pusilla L. The structures of the isolated compounds were assigned by spectroscopic methods, including 1D and 2D homo and heteronuclear NMR experiments, ESI-MS, chemical transformation and comparison with literature data.
Subject(s)
Fabaceae/chemistry , Plant Extracts/chemistry , ortho-Aminobenzoates/chemistry , Magnetic Resonance Spectroscopy , Molecular StructureABSTRACT
Two new spiro-γ-lactone glycosides named microphynolide A (1) and microphynolide B (2), together with twelve known compounds including five biflavonoids namely neochamaejasmin A, neochamaejasmin B, daphnodorin B, genkwanol A and stelleranol, one bis-coumarin daphnoretin, two lignans called pinoresinol and matairesinol, one flavonoid glucoside, tiliroside, a sinapyl alcohol glucoside, syringin, and two phytosterols, ß-sitosterol and ß-sitosterol-3-O-glucoside, were isolated from ethyl acetate extracts of the aerial parts and roots of the plant Thymelaea microphylla Coss. and Dur. All the isolated compounds were characterised by using spectroscopic methods and comparison with the literature data.
Subject(s)
Glycosides/chemistry , Lactones/isolation & purification , Spiro Compounds/isolation & purification , Thymelaeaceae/chemistry , Algeria , Flavonoids/chemistry , Flavonoids/isolation & purification , Glycosides/isolation & purification , Lactones/chemistry , Lignans/chemistry , Lignans/isolation & purification , Molecular Structure , Plant Components, Aerial/chemistry , Plant Extracts/chemistry , Plant Roots/chemistry , Spiro Compounds/chemistryABSTRACT
Three new abietane-type diterpenoids: ent-abieta-8,11,13-trien-16-ol (1), ent-abieta-8,11,13-trien-11,16-diol (2) and 11,12-dihydroxy-7-oxo-ent-abieta-8,11,13-trien-16-oic acid methyl ester (3), in addition to three known triterpenoids: euphol (4), 24,25-epoxycycloartanol (5) and beta-sitosterol O-beta-D-glucoside (6) were isolated from the chloroform extract of the roots of Euphorbia guyoniana. Structures of the isolated compounds were established on the basis of spectroscopic analyses, including 1D and 2D homo and heteronuclear NMR experiments and ESIMS, and comparison with literature data.