RP-UHPLC-ESI-QTOF-MS analyses and evaluation of the antioxidant, antimicrobial, anti-diabetic and anti-Alzheimer activities of Linum tenue Desf.

The polyphenolic compounds of the n-butanol fraction of Linum tenue Desf. (BFLTe) were characterised by RP-UHPLC-ESI-QTOF-MS analyses with the main presence of 6,8-di-C-glucosyl naringenin (11.7%), vicenin 2-isomer 2 (8.18%), luteolin-7,3'-di-O-ß-D-glucoside (7.18%), isovitexin (5.98%), luteolin-7-O-ß-D-glucoside (5.713%), myricitrin (4.41%), luteolin-4'-O-ß-D-glucoside (4.04%), chlorogenic acid (28.68%), 3-(2,6-dihydroxyphenyl)-4-hydroxy-6-methyl-3H-2-benzofuran-1-one (8.17%) and p-coumaric acid (4.0%.). The antioxidant capacity was evaluated using three complementary methods (DPPH, ABTS and Reducing power). Additionally, the antimicrobial activity was tested against eight bacterial strains and the fungi Candida albicans whereas the antidiabetic activity was performed against α-amylase. The anti-Alzheimer activity was tested by inhibiting the butyrylcholinesterase (BChE). The BFLTe showed, for the first-time, a good antioxidant potential in DPPH (IC50:68.83 ± 2.74 µg/mL), ABTS (IC50:48.73 ± 1.07 µg/mL) and Reducing power assays (A0.50:99.98 ± 1.18 µg/mL) and a moderate antimicrobial activity with 250 and 500 µg/mL MICs values. Moreover, the fraction exhibited an excellent inhibition of the BChE (IC50:33.00 ± 0.85 µg/mL) and α-amylase (IC50:1093.13 ± 12.93 µg/mL).

Phytochemical study, antioxidant and tyrosinase inhibitory activities of Pentzia monodiana Maire.

Chemical investigation of the aerial parts of Pentzia monodiana Maire led to the isolation and identification of one sesquiterpene lactone glucoside of the guaianolide type (dihydropseudoivalin-4-O-ß-d-glucopyranoside), along with nine known compounds including one diterpenoid, two sesquiterpenoids, three lignanes and three flavonoids. Their structures were established on the basis of spectroscopic analysis. All these compounds were evaluated for their DPPH radical scavenging and tyrosinase inhibitory activities. Only lignanes and flavonoids showed good to moderate DPPH radical scavenging activity with EC50 ranging from 10.6 to 47.5 µM. The new sesquiterpene lactone glucoside showed low tyrosinase inhibitory activity whereas the isolated lignanes and flavonoids exhibited a moderate activity with IC50 ranging from 45.4 to 97.2 µM).

RP-UHPLC-ESI-QTOF-MSn analyses, antioxidant, antimicrobial, analgesic activities and toxicity of Achillea ligustica All.

Fourty five polyphenols were identified in the hydroethanol extract of Achillea ligustica All. by LC-HRMS/MS with caffeoyl-6-oleside (5.74%), eucommin A (4.03%), quercetin-3-O-ß-D-glucoside (3.13%) and cirsimaritin (2.95%) as the major compounds. A good antioxidant potential was shown in DPPH, ABTS and phenanthroline tests and the highest antioxidant activity (A0.5:36.23 ± 3.07 µg/mL), which was close to the standard α-tocopherol, was shown in Reducing power. The extract inhibited the growth of all tested microorganisms with MICs ranging between 10 and 190 µg/mL. In the acute toxicity test, no death was observed at doses of 100, 750 and 1500 mg/Kg with DL50 higher than 2000 mg/Kg. In analgesic in vivo assay, the extract showed a very important capacity to reduce pain, whether central or peripheral, with a certain dose-dependent relationship. For the three tests (tail flick, hot plate and acetic acid assay), the effective dose was 750 mg/kg.

A new acylated flavonol triglycoside and evaluation of the antioxidant activity of Astragalus armatus subsp. numidicus (Murb.) Emb. & Maire.

A new acylated flavonol triglycoside, quercetin-3-O-(5'-p-hydroxybenzoyl)-ß-D-apiofuranosyl-(1→2)[α-L-rhamnopyranosyl-(1→6)]-ß-D-galactopyranoside (1), was isolated from the aerial parts of Astragalus armatus subsp. numidicus (Murb.) Emb. & Maire as well as ten known compounds, one phenolic compound, one flavonol-aglycone and eight flavonol-glycosides distributed into two monoglycosides, three diglycosides and three triosides. Their structures were mainly determined by 1D- and 2D-NMR experiments (1H,13C, COSY, HSQC, HMBC). The chloroform, ethyl acetate, n-butanol and hydroethanol extracts were tested for their antioxidant activity using five methods (DPPH, ABTS, Reducing power, CUPRAC and Phenanthroline). The ethyl acetate extract was the most active in CUPRAC (A0.5: 50.28 ± 2.16 µg/mL), ABTS (IC50: 49.73 ± 1.55 µg/mL) and Reducing power (A0.5: 58.13 ± 4.35 µg/mL) assays, whereas the hydroethanol and n-BuOH exhibited the highest activity in the Phenanthroline assay (A0.5: 9.93 ± 0.16) and (A0.5: 10.27 ± 0.44 µg/mL), respectively.

Biological activities and polyphenolic profile of Stachys arvensis (L.) L.

The n-butanol extract of Stachys arvensis (L.) L. aerial parts (BESA) was analysed by LC-HRMS/MS. 43 Polyphenols, including flavonoids, cinnamic acid derivatives, phenylethaoids, chromones, gallotannins, coumarins and chalcones with hyperoside (13.85%), panasenoside (10.31%), myricitrin (7.89%) and sayaendoside (7.16%), as the major compounds, were identified. High total phenolics (470.21 ± 1.22 mg GAE/g extract) and total flavonoids (189.05 ± 0.72 mg QE/g extract) contents were measured. In addition, the BESA exhibited a higher antioxidant effect in CUPRAC (A0.5:0.45 ± 0.03 µg/mL), DPPH (IC50:4.51 ± 0.16 µg/mL) and ABTS (IC50:7.10 ± 0.18 µg/mL) assays than the standards BHA and α-Tocopherol. Moreover the extract showed a good inhibitory effect against BChE (IC50: 145.02 ± 0.03 µg/mL) and α-amylase (IC50:2.66 ± 0.0024 mg/mL). The BESA exhibited an excellent anti-inflammatory activity (IC50:416 ± 0,056 µg/mL) which was close to that of acetylsalicylic acid, used as a control. The BESA was toxic towards T. molitor larvae and it possessed a good antibacterial activity against gram (+) and gram (-) tested strains.

A new triterpene saponin and known compounds from the polar extract of Salvia argentea L. and evaluation of their antioxidant activity.

A new triterpene saponin, 2, 3, 21, 23-tetrahydroxyolean-12-en-28-oic-acid-28-O-ß-D- glucosyl-(2''→1')-ß-D-glucoside (1), was isolated from the n-butanol extract of dried aerial parts of Salvia argentea L. (Lamiaceae) in addition to two known flavonoids, apigenin 7-O-ß-D-glucoside (2), threo-guaiacylglycerol 3-O-[6-O-p-hydroxybenzoyl]-ß-D-glucoside (3), luteolin 7-O-ß-D-glucoside (4), verbascoside (5) and rosmarinic acid (6). The structure elucidation of these compounds was based on analyses of spectroscopic data including 1D-, 2D-NMR and HR-ESI-MS techniques and by comparing their NMR data with those reported in the literature. Compound 6 exhibited the highest antioxidant activity in DPPH assay (IC50<3.00 µg/mL) which was better than the standards BHA, BHT, Trolox and ascorbic acid.

Triterpenoid saponins from Anagallis monelli ssp. linifolia (L.) Maire and their chemotaxonomic significance.

Thirteen undescribed triterpenoid saponins named monellosides A-M, were isolated from the aerial parts of Anagallis monelli ssp. linifolia (L.) Maire, together with ten known oleanane-type glycosides. Their structures were elucidated by 1D and 2D-NMR spectroscopy (COSY, TOCSY, HSQC, HMBC and ROESY) as well as high resolution mass spectrometry (HR-ESI-MS) and acid hydrolysis. Monellosides A-M have a carbohydrate chain linked on the C-3 of the aglycone with a common ß-d-glucopyranosyl-(1 â†’ 4)-α-l-arabinopyranosyl sequence which was further glycosylated by a glucose and/or a xylose. The sequence ß-d-xylopyranosyl-(1 â†’ 2)-ß-d-glucopyranosyl-(1 â†’ 4)-[ß-d-glucopyranosyl-(1 â†’ 2)-]α-l-arabinopyranosyl was common to all the 13,28-epoxy-oleanane core skeleton except one compound. In order to discuss the reclassification of Anagallis in Primulaceae, we compared saponins from species of Myrsinaceae and Primulaceae families and showed that these species were characterized by a pentacyclic triterpenoid saponin with a 13,28-epoxy bridge skeleton. Our phytochemical results increase the knowledge of saponins of the genus Anagallis, their chemotaxonomy and stimulate the evaluation of the biological activities of these saponins.

Chemical composition and biological potential of Thymus Willdenowii Boiss. & Reut. essential oil.

The fresh aerial parts of Thymus willdenowii Boiss. & Reut. (syn. Thymus hirtus Willd.) were hydrodistilled in a Clevenger type apparatus and analyzed by GC and GC-MS. 44 Components were identified representing 97.3%, with 1,8-cineole (34.62%), camphor (18.55%), α-pinene (9.46%) and camphene (5.38%) as the main components. T. willdenowii essential oil was not cytotoxic (CC50 = 97.65 µg/mL) towards Vero non-tumoural cells, exhibiting good antibacterial and antiproliferative (30.8 ± 3.1% inhibition) potentials against four tested pathogenic bacteria and Human colorectal cell line HT-29, respectively. The essential oil did not show a DPPH radical scavenging activity, by Electron Spin Resonance spectroscopy (ESR), and it lacks antiviral effect towards coxsackievirus B3.

Triterpene saponins from Silene gallica collected in North-Eastern Algeria.

Eleven previously undescribed triterpene saponins, named silenegallisaponin A-K (1-11), were isolated from the aerial parts of Silene gallica L. Their structures were elucidated by analysis of 1D and 2D-NMR spectroscopic data and mass spectrometry (HR-ESI-MS). The saponins comprised caulophyllogenin, echinocystic acid, or quillaic acid substituted at C-3 by a ß-d-glucuronic acid or ß-d-galactopyranosyl-(1 â†’ 3)-ß-d-glucuronopyranoside and at C-28 by a ß-d-fucopyranose substituted at C-2 by a ß-d-glucose and at C-3 by a ß-d-glucose or a ß-d-quinovose.

6"'-O-acetylisospinosin, a new C-glycosylflavone and known compounds from the aerial parts of Cladanthus mixtus.

A new C-glycosylflavone, identified as 6"'-O-acetylisospinosin (1), was isolated from the aerial parts of Cladanthus mixtus together with 30 known compounds. The structures of these compounds were established by interpretation of their spectral data, mainly UV, 1D and 2D NMR spectroscopic methods including (1H and 13C NMR, COSY, ROESY, HSQC and HMBC experiments), ESI-MS, and by comparison with the literature data.

Triterpenes from Salvia argentea var. aurasiaca and their antibacterial and cytotoxic activities.

Five undescribed ursane-type triterpenes, identified as 1ß,3ß,15α-trihydroxy-urs-9(11)-12-diene (1), 1ß,3ß,15α,28-tetrahydroxy-urs-9(11),12-diene (2), 1ß,3ß-dihydroxy-urs-9(11),12-dien-28-al (3), 1ß,3ß,7ß,15α,28-pentahydroxy-urs-12-ene (4), and 1ß,3ß,15α-trihydroxy-urs-11-en-28-al (5), together with five known compounds (6-10), were isolated from the acetone extract of the dried aerial parts of Salvia argentea L. var. aurasiaca (Pomel) Batt. et Trab. (Lamiaceae). Structures were elucidated on the basis of extensive spectroscopic analysis including HR-ESI-MS, 1D- and 2D-NMR techniques and comparison with literature data. The antibacterial evaluation of compounds 1-10 of the acetone extract of the dried aerial parts, in addition to nine compounds (11-19) previously isolated from the extract of the fresh aerial parts, by bioautography on Staphylococcus aureus followed by the determination of MIC values of active compounds by serial dilution technique against five bacteria, revealed that two compounds have an antibacterial effect comparable to antibiotics. The cytotoxic activity evaluation of compounds 1-19 showed that Six compounds exhibited an antiproliferative activity against K562 and HT1080 cells with IC50 values ranging from 30.25 to 70.32 µM.

Phytochemistry and Antioxidant Activity of Aerial Parts of Phagnalon sordidum L.

One new natural monoterpene, 5-O-ß-d-glucopyranosyl-2-hydroxy-p-cymene (1: ), and 11 known compounds were isolated through a biologically oriented approach from the aerial parts of Phagnalon sordidum L. The most active extract and fractions were selected using 3 complementary antioxidant activity assays. Results and the different methods were compared by relative antioxidant capacity index. In addition, the most active extract of P. sordidum was subjected to liquid chromatography coupled with electrospray ionization hybrid linear ion trap quadrupole Orbitrap mass spectrometry to quantify secondary metabolites. Antioxidant activities of ethyl acetate extract, and purified 3,4-dihydroxyacetophenone (3: ) and nebrodenside A (7: ) were demonstrated by in vitro cell free model assays, and their protective effect against H2O2-induced oxidative stress in a HepG2 (human hepatocellular carcinoma) cell line was established.

Guaianolides from Ormenis mixta: Structural Insights and Evaluation of Their Anti-inflammatory Profile.

In this paper, the isolation of five new guaianolides (1:  - 5: ) and four (6:  - 9: ) known sesquiterpenes from Ormenis mixta aerial parts is reported. The structural determination of the guaianolides was obtained by NMR spectroscopic data, as well as MS experiments. Their relative configurations were assigned by a combined quantum mechanical/NMR approach, comparing the experimental 13C/1H NMR chemical shift data and 1 J H-H homonuclear coupling constants with the related predicted values. The isolates were assayed for their anti-inflammatory potential evaluating nitric oxide release and cyclooxygenase-2 expression in J774A.1 macrophages treated with lipopolysaccharide from Escherichia coli. Our results indicated that, among the tested compounds, 1:  - 3: , and 7: were able to inhibit nitric oxide release, while all were able to inhibit cyclooxygenase-2 expression with different potencies.

Triterpenoid saponins from Scabiosa stellata collected in North-eastern Algeria.

Eight undescribed triterpenoid saponins, scabiostellatosides A-H, together with three known compounds were isolated from the whole plant of Scabiosa stellata L. Their structures were established by spectroscopic analyses (1D, 2D-NMR and HRESIMS) and chemical methods. Scabiostellatosides A-H were evaluated for their cytotoxicity against human fibrosarcoma cell line (HT1080). Scabiostellatoside F, a heptasaccharide derivative of oleanolic acid, exhibited moderate cytotoxicity against HT1080 cell line with IC50 value of 12.0 µM.

A new 2-alkylhydroquinone glucoside from Phagnalon saxatile (L.) Cass.

A new 2-alkylhydroquinone glucoside, 1-O-ß-d-glucopyranosyl-1,4-dihydroxy-2-((E) 2-oxo-3-butenyl)benzene (1), in addition to nine known compounds were isolated from the aerial parts of Phagnalon saxatile (L.) Cass. (Asteraceae). Their structures were identified based on spectroscopic methods including 1D and 2D NMR, mass spectrometry (HR-ESI-MS), UV spectral analyses and by comparison with literature data. The cytotoxic activity of three isolated compounds (1-3) was evaluated against fibrosarcoma (HT1080), human lung cancer (A549) and breast cancer (MCF7) cell lines.

Two new bis-iridoids isolated from Scabiosa stellata and their antibacterial, antioxidant, anti-tyrosinase and cytotoxic activities.

This study presents the chemical profile investigation of a 70% ethanol extract obtained from Scabiosa stellata, a medicinal herbaceous traditionally used to treat heel cracks. A 13C NMR-based dereplication methodology was firstly applied on centrifugal partition chromatography-generated fractions in order to quickly identify the major compounds of the extract. The dereplication process was then completed by semi-preparative high-performance liquid chromatography in order to identify unknown or minor compounds. Two new bis-iridoids, namely 7-O-caffeoyl-sylvestroside I (1) and 7-O-(p-coumaroyl)-sylvestroside I (2), together with ten known compounds (3-12) were isolated. Their structures were elucidated by spectroscopic methods including NMR and HR-ESI-MS. The antibacterial, anti-tyrosinase and DPPH radical scavenging activities of the crude extract, fractions, and isolated compounds were evaluated. A significant antibacterial activity was observed for nine isolated compounds, particularly 1 and 2 which yielded MIC values of 31.2µg/mL against Enterococcus faecalis and 62.5µg/mL against Staphylococcus epidermidis. The cytotoxic activity of these new bis-iridoids was evaluated on a fibrosarcoma cell line (HT1080) and only compound 1 exhibited a moderate cytotoxic activity (IC50 35.9µg/mL).

Chemical composition and antioxidant activity of aerial parts of Ferula longipes Coss. ex Bonnier and Maury.

This is the first study on the phytochemistry and antioxidant activity of Ferula longipes Coss. ex Bonnier and Maury (Apiaceae). A new flavonoid quercetin-3-O-α-L-rhamnopyranoside-7-O-ß-D-[2-O-caffeoyl]-glucopyranoside (1), along with 10 known compounds kaempferol-3-O-α-L-rhamnopyranoside (2), quercetin-3-O-α-L-rhamnopyranoside (3), kaempferol-3-O-ß-D-glucopyranoside-7-O-α-L-rhamnopyranoside (4), isorhamnetin-3-O-α-L-rhamnopyranoside-7-O-ß-D-glucopyranoside (5), quercetin-3-O-α-L-rhamnopyranoside-7-O-ß-D-glucopyranoside (6), isorhamnetin-3,7-di-O-ß-D-glucopyranoside (7), apigenin (8), apigenin-7-O-ß-D-glucopyranoside (9), 3,5-dicaffeoylquinic acid (10), deltoin (11) were isolated from the aerial parts of Ferula longipes Coss. Structures elucidation was performed by comprehensive 1D and 2D NMR analyses, mass spectrometry and by comparison with literature data. The compounds 1, 3, 4, 6, 7 and 10 were evaluated for their antioxidant activity, compound 1 exhibited the best antiradical activity potential and showed IC50 and A0.5 values 5.70, 7.25, 5.00, and 2.63 µg/mL towards DPPH free radical-scavenging, ABTS, CUPRAC, and reducing power assays, respectively compared with BHA, BHT and ascorbic acid which were used as positive controls.

Antibacterial, antioxidant and cytotoxic activities of triterpenes and flavonoids from the aerial parts of Salvia barrelieri Etl.

From the aerial parts of Salvia barrelieri Etl. (Lamiaceae), 12 compounds including a new triterpene, 3ß-acetoxy-olean-18-ene-2α-ol, were isolated. Their structures were established by the combination analyses of spectroscopy including 1D-, 2D-NMR and HRESIMS and in comparison with the reported data in the literature. The antibacterial activity of these compounds was evaluated by bioautography on Staphylococcus aureus followed by the determination of MIC values by serial dilution technique against five bacteria. Three compounds were active against Enterococcus faecalis, S. aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosa (MIC 15.1 to 125 µg/mL). Two compounds showed moderate DPPH radical scavenging activity (IC50 79.1 and 21.2 µg/mL). These compounds did not show significant tyrosinase inhibitory activities (IC50> 1.5 mg/mL). Their cytotoxic activity was evaluated against promyelocytic leukaemia (HL60), human erythromyeloblastoid leukaemia (K562) and fibrosarcoma (HT1080) cell lines and four compounds exhibited a moderate cytotoxic activity (IC50 28.75 to 85.0 µM).

Flavonoids, cytotoxic, antioxidant and antibacterial activities of Evax pygmaea.

CONTEXT: Phytochemical study and biological potential of Evax pygmaea (L.) Brot. (Asteraceae) are reported for the first time. OBJECTIVE: To identify the secondary metabolites of Evax pygmaea and to determine its antioxidant, antibacterial and cytotoxic activities. MATERIALS AND METHODS: Dried aerial parts (1 kg) were macerated in 70% MeOH (5 L) during 72 h. The concentrated hydromethanolic extract was subjected to extractions with chloroform (3 × 300 mL), ethyl acetate (3 × 300 mL) and n-butanol (3 × 300 mL), successively. VLC of combined ethyl acetate (EAEP) and n-butanol (BEP) fractions was followed by column purifications. Antioxidant activity was investigated using DPPH, CUPRAC, and metal chelating, ß-carotene/linoleic acid and ABTS assays. Agar method was used in the antibacterial study. Cytotoxic activity was determined by Brine shrimp lethality test in DMSO and ethanol, at varying concentrations (2, 1 and 0.2%) and (1, 0.2 and 0.1%) successively. RESULTS: Quercetin (1), isorhamnetin 3-O-ß-d-xyloside (2), isorhamnetin 3-O-ß-d-glucoside (3), quercetin 3-O-ß-d-glucoside (4), quercetin 7-O-ß-D-glucoside (5), patuletin 3-O-ß-d-glucoside (6) were isolated from for the first time from Evax genus. The EAEP was the most active in ABTS (IC50: <3.125 µg/mL) assay whereas the BEEP exhibited the highest activity in the ß-carotene/linoleic acid assay (IC50: <3.125 µg/mL). The EAEP and BEP exhibited good antibacterial activity (MIC: 40-80 µg/mL). The plant did not show any toxicity (LD50>80 µg/mL). DISCUSSION AND CONCLUSIONS: Six flavonoids were isolated for the first time from Evax pygmaea which exhibited good antioxidant and antibacterial activities.

Oleanane-type triterpene saponins from Calendula stellata.

Five previously undescribed bisdesmosidic triterpenoid saponins named calendustellatosides A-E, along with fifteen known compounds were isolated from the 70% ethanol whole plant extract of Calendula stellata Cav. (Asteraceae). Their structures were determined by 1D- and 2D-NMR spectroscopy as well as high resolution mass spectrometry and acid hydrolysis. The saponins comprised oleanolic acid, echinocystic acid, morolic acid or mesembryanthemoidigenic acid as the aglycones and saccharide moieties at C-3 and C-28. Like most Calendula saponins, the sugar moiety linked at C-3 was either ß-d-glucose or ß-d-glucuronic acid which could be substituted at C-3 by a ß-d-galactose and/or C-2 by a supplementary ß-d-galactose or a ß-d-glucose. The sugar moiety linked to C-28 was determined as ß-d-glucose. The antibacterial evaluation of compounds 1-20 by bioautography on Staphylococcus aureus followed by the determination of MIC values of active compounds by serial dilution technique against 5 bacteria revealed that; calendustellatoside D was the most active against Enterococcus faecalis with an antibacterial effect comparable to antibiotics. The cytotoxic activities of isolated compounds were evaluated against fibrosarcoma cell line (HT1080) and human lung cancer cell line (A549). Calendustellatosides B and D exhibited a low cytotoxic activity against HT1080 cell line with IC50 values of 47 ± 0.6 and 39 ± 0.5 µM, respectively.