Chemical composition,antioxidant, antibacterial and cytotoxic activities of essential oil of Leontopodium leontopodioides (Willd.) Beauverd

The essential oil (EO) from the aerial parts of Leontopodium leontopodioides (Willd.) Beauverd was obtained by hydrodistillation and analysed by GC–FID and GC–MS. Sixty-five compounds were identified which represent 96.2% of the total composition of the EO. The major components of the EO were palmitic acid (11.6%), n-pentadecanal (5.7%), linalool (3.8%), β-ionone (3.3%), hexahydrofarnesyl acetone (3.2%), bisabolone (3.2%) and β-caryophyllene (3.2%). The EO exhibited an excellent antibacterial activity against Staphylococcus aureus and Bacillus subtilis according to the MIC values tested by micro-dilution method. It also exhibited a significant cytotoxicity against HepG2 and MCF-7 cell lines with the IC₅₀ values of 67.44 and 70.49 μg/mL according to the MTT assay. However, the antioxidant activity test revealed that the EO exhibited a weak DPPH radical-scavenging activity. In conclusion, the EO of L. leontopodioides could be regarded as a bioactive natural product and deserves further study for its potential therapeutic effects.     

Chemical composition,antimicrobial and antioxidant activities of the essential oil of Psammogetoncanescens

This study reports the chemical composition, antimicrobial activity and antioxidant properties of Psammogeton canescens essential oil (EO) and its main compounds. The EO was obtained from the aerial parts of P. canescens by hydrodistillation and analysed by using GC/MS. The main constituent was β-bisabolene (25%), followed by α-pinene (20%), apiole (15.34%), γ-terpinene (7.34%), p-cymene (5.35%), β-pinene (5.41%), camphene (5.12%), dill apiole (5%), myrcene (4.54%), colchicine (0.56), sylvestrene (0.56%), β-caryophyllene (0.45%), caryophyllene oxide (0.43%), (Z)-β-farnesene (0.32%), cembrene (0.21%), folic acid (0.21%), germacrene D (0.14) and β-sesquiphellandrene (0.13). β-Bisabolene exhibited strong antioxidant activity (14 ± 0.8 μg/mL). The EO of P. canescens was particularly active against Candida albicans and Escherichia coli, with the lowest minimum inhibitory concentration and minimum bactericidal/fungicidal concentration values. In conclusion, these results support the use of the EO and its main compounds for their antioxidant properties and antimicrobial activity.     

Essential oil and fractions isolated of Laurel to control adults and larvae of cattle ticks

Abstract

This study, was to evaluate the acaricidal effect of the essential oil (EO) and fractions (FR) obtained from Laurus nobilis leaves on Rhipicephalus (Boophilus) microplus. Eight fractions were obtained, however FR1: sabinene (37.83%), β-pinene (13.50%), 1,8-cineole (12.66%), α-pinene (12.56%) and FR8: α-terpineol (79.19%) were highlighted as to the larvicidal potential when submitted by Larval Packet Test. The EO was tested by the Adult Immersion Test, at concentrations of 200.00; 100.00 and 50.00?µL/mL caused mortality of engorged females, egg mass reduction and hatching inhibition. Two fractions are shown to be efficient in controlling larvae FR8 (LC₅₀?=?0.13?µL/mL, LC₉₉?=?0.51?µL/mL) and FR1 (LC₅₀?=?0.20?µL/mL, LC₉₉?=?0.56?µL/mL). The fractionation of EO was determinant to elucidate which compounds were responsible for the larvicidal potential. This study opens new perspectives to direct new bioassays with the compounds obtained in the fractionation, since they present high potential on cattle tick larvae.     

Chemical Composition,Antibacterial, Anti-Inflammatory,and Enzyme Inhibitory Activities of Essential Oil from Rhynchanthus beesianus Rhizome

Rhynchanthus beesianus W. W. Smith, an edible, medicinal, and ornamental plant, is mainly cultivated in China and Myanmar. The essential oil (EO) from R. beesianus rhizome has been used as an aromatic stomachic in China. The chemical composition and biological activities of EO from R. beesianus rhizome were reported for the first time. Based on gas chromatography with flame ionization or mass selective detection (GC-FID/MS) results, the major constituents of EO were 1,8-cineole (47.6%), borneol (15.0%), methyleugenol (11.2%), and bornyl formate (7.6%). For bioactivities, EO showed a significant antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Proteus vulgaris with the diameter of the inhibition zone (DIZ) (8.66–10.56 mm), minimal inhibitory concentration (MIC) (3.13–6.25 mg/mL), and minimal bactericidal concentration (MBC) (6.25–12.5 mg/mL). Moreover, EO (128 μg/mL) significantly inhibited the production of proinflammatory mediators nitric oxide (NO) (92.73 ± 1.50%) and cytokines tumor necrosis factor-α (TNF-α) (20.29 ± 0.17%) and interleukin-6 (IL-6) (61.08 ± 0.13%) in lipopolysaccharide (LPS)-induced RAW264.7 macrophages without any cytotoxic effect. Moreover, EO exhibited significant acetylcholinesterase (AChE) inhibitory activity (the concentration of the sample that affords a 50% inhibition in the assay (IC₅₀) = 1.03 ± 0.18 mg/mL) and moderate α-glucosidase inhibition effect (IC₅₀ = 11.60 ± 0.25 mg/mL). Thus, the EO could be regarded as a bioactive natural product and has a high exploitation potential in the cosmetics and pharmaceutical industries.     

Chemical constituents of Genista numidica Spach aerial parts and their antimicrobial,antioxidant and antityrosinase activities

A previously undescribed triterpenoid saponin, 3-O-[α-l-rhamnopyranosyl-(1→2)-{β-d-glucopyranosyl-(1→6)-}β-d-galactopyranosyl-(1→2)-β-d-glucuronopyranosyl]-sophoradiol (1), in addition to twenty-nine known constituents (2–30) were isolated from the aerial parts of Genista numidica Spach. Structures elucidation was performed by comprehensive 1D- and 2D-NMR analyses and HRESIMS. The extracts, fractions and isolated compounds were evaluated for their antibacterial, antioxidant and tyrosinase inhibitory activities. The experimental findings indicated that genistin (16), isosalipurpol (27), and koaburaside (29) have moderate to low antibacterial activity against E. faecalis, S. aureus, S. epidermidis and P. aeruginosa bacteria with MICs ranging from 31.2 to 125 μg/mL. Compounds 19 and 27 exhibited a good antiradical activity potential (IC₅₀ 11.8 and 11.1 μg/mL, respectively). Only compounds 23, 27 and 28 exhibited low inhibitory effect against mushroom tyrosinase (IC₅₀ from 90.2 to 225.6 μg/mL).     

New cytotoxic bufadienolides from the roots and rhizomes of Helleborus thibetanus Franch

Abstract

Three new bufadienolides 14β, 16β-dihydroxy-3β-[β-D-glucopyranosyl-(1→6)-(β-D-glucopyranosyl)oxy]-5α-bufa-20, 22-dienolide (1), 14β-hydroxy-3β-[β-D-glucopyranosyl-(1→4)-(β-D-glucopyranosyl)oxy]-5α-bufa-20, 22-dienolide (2) and hellebrigenin-3-O-β-D-glucosyl-(1→4)-β-D-glucoside (3), together with eight known bufadienolides (4–11) were isolated from the roots and rhizomes of Helleborus thibetanus. Their structures were elucidated by extensive spectroscopic methods and acid hydrolysis. Compounds 1–7 were evaluated for their cytotoxic activity against HCT116, A549 and HepG2 tumor cell lines. Compound 1 exhibited moderate cytotoxicity against HepG2 cells with IC₅₀ value of 15.1?±?1.72?μM. Compounds 5 and 6 exhibited moderate cytotoxicity against HCT116 cells with IC₅₀ values of 15.12?±?0.58?μM and 13.17?±?2.34?μM, respectively.     

Chemical constituents and cytotoxic activity from the wood-decaying fungus Xylaria sp. SWUF08-37

Abstract

A new cyclic pentapeptide, pentaminolarin (1), and a new cytochalasin, xylochalasin (2), along with thirteen known compounds (3–15) were isolated from the wood-decaying fungus Xylaria sp. SWUF08-37. The absolute configurations of 1 were determined by a combination of Marfey’s method and TDDFT ECD calculation and the absolute configurations of 2 were established by TDDFT ECD calculation. Compound 12 showed moderate cytotoxicity against HeLa (IC₅₀?=?19.60?µg/mL), HT29 (IC₅₀?=?17.31?µg/mL), HCT116 (IC₅₀?=?14.28?µg/mL), MCF-7 (IC₅₀?=?15.38?µg/mL), and Vero (IC₅₀?=?24.97?µg/mL) cell lines by MTT assay. Compounds 1 and 2 showed slight cytotoxicity against all tested cancer cell lines.     

Two new benzophenones and one new natural amide alkaloid isolated from a mangrove-derived Fungus Penicillium citrinum

Two new compounds penibenzophenones A-B (1–2), and the synthetic α,β-unsaturated amide alkaloid (E)-tert-butyl(3-cinnamamidopropyl)carbamate (4), newly identified as a natural product, alone with three known ones (3, 5–6) were isolated from the EtOAc extract of the endophytic fungus Penicillium citrinum HL-5126 isolated from the mangrove Bruguiera sexangula var. rhynchopetala collected in the South China Sea. Compound 1 was a chlorinated benzophenone. The structures of 1–6 were elucidated by extensive NMR spectral interpretation, MS data and X-ray analysis. The new compound 2 displayed cytotoxic activity against human A549 cell lines with an IC₅₀ value of 15.7 μg/mL, and 1 showed antibacterial activity against Staphylococcus aureus with a MIC value of 20 μg/mL.     

Antiglycation,antioxidant, and cytotoxic activities of Uvaria chamae root and essential oil composition

Abstract

Uvaria chamae (Annonaceae), is an essential oil bearing plant; the root is acclaimed as an effective remedy for folkloric diabetic therapy. The root extracts were evaluated for composition, antiglycation, antioxidant, and cytotoxicity. Flavonoids, cardiac glycosides, and tannins were relatively high in the alcohol extract; benzyl benzoate (23.3%), dimethoxy-p-cymene (14.2%), τ-cadinol (12.1%), and methyl thymol (8.7%) predominated the constituents identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The ethanol extract demonstrated significant antiglycation activity (IC₅₀, 1.12?mg/mL), and cytotoxicity to brine shrimp (LC₅₀, 25.01?µg/mL). The extract (IC₅₀, 8.0?µg/mL; absorbance 0.531, 100?µg/mL) also exhibited better antioxidant effects compared with the essential oil (IC₅₀, 50.0?µg/mL; absorbance 0.292, 100?µg/mL) using 2,2-diphenyl-1-picrylhydrazyl radical and ferric reducing power assays respectively. U. chamae root possess antiglycation effect, and may also reduce oxidative stress in patients with diabetes; its antiglycation effect, oil composition, and cytotoxicity are reported for the first time.

     

Chemical composition,protoscolicidal effects and acute toxicity of Pistacia atlantica Desf. fruit extract

The present study was designed to evaluate the chemical composition and scolicidal effects of Pistacia atlantica Desf. extract against protoscoleces of hydatid cysts and its acute toxicity in mice model. Various concentrations of the methanolic extract (5–50 mg/mL) were used for 10–60 min. Viability of protoscoleces was confirmed using eosin exclusion test (0.1%). Acute toxicity was also determined in mice model. The main components were β-myrcene (41.4%), α-pinene (32.48%) and limonene (4.66%). Findings demonstrated that P. atlantica extract at the concentrations of 25 and 50 mg/mL after 20 and 10 min of exposure killed 100% protoscoleces. The LD₅₀ of the intraperitoneal injection of the P. atlantica methanolic extract was 2.43 g/kg and the maximum non-fatal dose was 1.66 g/kg. Obtained results showed the potential of P. atlantica extract as a natural source with no significant toxicity for the production of new scolicidal agent to use in hydatid cyst surgery.     

Bioactive glycosides from the African medicinal plant Boerhavia erecta L.

Phytochemical studies of the previously unexplored stem of Boerhavia erecta from Burkina Faso, resulted in the isolation of an unreported glycoside 4, 2,3-dihydroxypropylbenzoate-3-O-β-[4″-methoxy] glucuronide as well as seven known glycosides (1–3, 5–8). The major isolate 5 and 8 indicated a significant inhibition against HIV integrase (IC₅₀ 10 and 22 μg/mL, respectively). The extracts and isolates were also tested for anti-malarial activity, but insignificant activity was observed.     

Chemical composition and biological activities of Iranian Achillea wilhelmsii L. essential oil: a high effectiveness against Candida spp. and Escherichia strains

In the case of Achillea wilhelmsii, 30 compounds were identified representing 94.48% of the total oil with a yield of 0.82% w/w. The major constituents of the oil were described as α-thujene (6.11%), α-pinene (5.11%), sabinene (5.23%), p-cymene (7%), 1,8-cineole (6%), linalool (10%), camphor (8.43%), thymol (18.98%) and carvacrol (20.13%). A. wilhelmsii oil exhibited higher antibacterial and antifungal activities with a high effectiveness against Escherichia coli and Candida albicans with the lowest minimum inhibitory concentration and minimum bactericidal concentration/minimum fungicidal concentration value (2 ± 0.0–2 ± 0.0 g/mL, 1 ± 0.5–1 ± 0.5 g/mL), respectively. Results showed that A. wilhelmsii oil exhibits a higher activity in each antioxidant system with a special attention for β-carotene bleaching test (IC₅₀: 19 μg/mL) and reducing power (EC₅₀: 10 μg/mL). Antioxidant activity-guided fractionation of the oil was carried out by TLC-bioautography screening and fractionation resulted in the separation of main antioxidant compounds which were identified as thymol (65%) and carvacrol (19%). In conclusion, these results support the use of the essential oil and its main compounds for their antioxidant properties and antimicrobial activity.     

Chemical composition,antioxidant and antiproliferative activities of essential oil from rhizome and leaves of Curcuma mutabilis Škorničk., M. Sabu & Prasanthk., endemic to Western Ghats of India

Abstract

Hydro-distilled essential oils, from fresh rhizomes and leaves of Curcuma mutabilis ?korni?k., M.Sabu & Prasanthk., characterized by GC–MS revealed the presence of thirty three and twenty three compounds therein respectively. Whilst estrone methyl ether (3-Methoxyestra-1,3,5(10)-trien-17-one) was the major component in rhizome oil (47.35%), sesquiterpene hydrocarbons predominated as the major group (63.92%) in leaf oil with a higher preponderance of β-caryophyllene (25.48%), β-farnesene (19.47%) and α-humulene (11.01%). Weak antioxidant activities observed in these oils determined by DPPH and ABTS methods were apparently influenced both by the oil composition and the assay conditions. Rhizome oil showed higher antiproliferative activity than leaf oil against leukemic K562 (IC₅₀-6.8µg/mL) and colorectal HCT116 (IC₅₀-8.5µg/mL) cancer cell lines. This first report reveals composition and biological activities of essential oils from C. mutabilis.     

Insecticidal,cytotoxic and anti-phytopathogenic fungal activities of chemical constituents from the aerial parts of Ferula sinkiangensis

Abstract

A new rare monoterpene coumarin (1) and its two known analogues (2–3), together with two sesquiterpenes (6–7) and ferulic acid (8) were isolated from the aerial parts of Ferula sinkiangensis. The structure of new compound was established on the basis of 1D and 2D NMR data and HRESIMS data interpretation. Insecticidal, cytotoxic and anti-phytopathogenic fungal activities of isolated compounds were evaluated against third-instar larvae of Spodoptera exigua and its cell line, and three plant pathogenic fungi respectively. Compounds 1–3 and 6–7 were found to be more effective contact toxicity to S. exigua with the corrected mortality values of 38.89%-58.89% at 10?μg/larva doses for 24?h. Further studies showed that compounds 3 and 6 exhibited cell growth inhibitory activity against S. exigua cell line with the EC₅₀ values of 22.78 and 14.64?µM for 72?h. In addition, compound 6 exhibited potent antifungal activity with MICs?=?16–32?µg/mL.     

Natural products as sources of new fungicides (II): antiphytopathogenic activity of 2,4-dihydroxyphenyl ethanone derivatives

A series of 17 simple 1-(2,4-dihydroxyphenyl) ethanones were synthesised, and their structures characterised by ¹H, ¹³C NMR and ESI-MS. Their in vitro antifungal activities were evaluated against five phytopathogenic fungi including Glomerella cingulate, Botrytis cirerea, Fusarium graminearum, Curvularia lunata and Fusarium oxysporum f. sp. vasinfectum by the mycelial growth inhibition assay. Compounds 2g and 2h exhibited broad-spectrum inhibitory activity against the mycelial growth of the tested pathogens with IC₅₀ values in the range of 16–36 μg/mL, and in particular being more active to G. cingulate, with IC₅₀ values of 16.50 and 19.25 μg/mL, respectively, than the other pathogens. Preliminary SAR indicated that an α,β-unsaturated ketone unit of the alkyl chain of the compounds is the structure requirement for fungicidal action. The results suggested that 2g and 2h may be promising leads in the development of new antifungal agents.     

Essential oil constituents,phenolic content and antioxidant activity of Lavandula stricta Delile growing wild in southern Iran

Lavandula stricta belongs to the Lamiaceae family and is considered as an endemic medicinal plant in southern Iran. Essential oil composition, total phenolic content and antioxidant activity from two different populations of L. stricta were studied for the first time. A GC and GC/MS analysis of essential oil isolated from the aerial part of L. stricta identified 31 constituents; the major constituents were α-pinene (58.34–63.52%), linalool (8.85–9.36%), 3-methyl butyl 2-methyl butanoate (7.45–7.70%), sabinene (2.84–3.56%), limonene (2.87–3.21%) and myrcene (2.25%). The total phenolic content of methanolic extracts was determined with the Folin–Ciocalteu reagent and the antioxidant activity of methanolic extract and essential oil were determined with the 2, 2-diphenyl-1-picryl hydrazyl free radical scavenging assay, respectively. Total phenols varied from 61.05 to 64.45 mg GAE/g dry weight, and IC₅₀ values in the radical scavenging assay ranged from 334.11 to 395.23 μg/mL in methanolic extracts and 420–475 μg/mL in essential oil.     

Synthesis,antimicrobial evaluation and docking study of triazole containing triaryl-1H-imidazole

An efficient route for the synthesis of triazole containing triaryl-1H-imidazole (3a–3r) was achieved involving multicomponent condensation of triazole aldehydes, ammonium acetate and 1,2-dicarbonyl compounds in glacial acetic acid. The structure of newly synthesized imidazoles was established by the FTIR, HRMS and NMR spectra. All the compounds displayed considerable antimicrobial activity against fungal and bacterial strains. The triazolyl imidazole 3p was substantially potent against P. aeruginosa (0.0113?µmol/mL), A. niger (0.0113?µmol/mL) and C. albicans (0.0056?µmol/mL) wherein triazolyl imidazoles 3i was found to be more potent against B. subtilis (0.0122?µmol/mL) & A. niger (0.0121?µmol/mL); and compound 3r was also found to be more potent against S. epidermidis (0.0117?µmol/mL) & C. albicans (0.0058?µmol/mL). As a result of docking studies, the binding affinity of the compound 3o was –9.6?kcal/mol which was even more in comparison to the binding affinity of co-crystallized ligand CBN (–9.4?kcal/mol).     

Preparation and characterization of PEPPSI-palladium N-heterocyclic carbene complexes using benzimidazolium salts catalyzed Suzuki–Miyaura cross coupling reaction and their antitumor and antimicrobial activities

New palladium complexes were efficiently synthesized from the reaction of benzimidazolium salts 2a–e, potassium carbonate (K₂CO₃) and palladium chloride (PdCl₂) in pyridine (for 3a–e). The catalytic activity of these complexes in a catalytic system including palladium complexes and K₂CO₃ in DMF-H₂O was evaluated in Suzuki–Miyaura cross-coupling reactions of aryl bromides and chlorides with phenylboronic acid. Our novel complexes show excellent catalytic activities with high turnover numbers (TON) and high turnover frequencies (TOF) (e.g. for the Suzuki–Miyaura reaction: TON up to 370 and TOF up to 123.3?h^?1). Both benzimidazolium salts 2a–e and complexes 3 have been characterized using spectroscopic data and elemental analysis. The antimicrobial activity of the N-heterocyclic carbene palladium complexes 3a–e varies with the nature of the ligands. Also, the IC₅₀ values of both, complexes (3a–e) and benzimidazoles 2a–e, have been determined. In addition, the new palladium complexes were screened for their antitumor activity. Complexes 3e and 3d exhibited the highest antitumor effect with IC₅₀ values 6.85?μg/mL against MCF-7 and 10.75?μg/mL against T47D, respectively.     

Diallyl Trisulfide,the Antifungal Component of Garlic Essential Oil and the Bioactivity of Its Nanoemulsions Formed by Spontaneous Emulsification

The aim of this study was to evaluate the chemical compounds of garlic essential oil (EO), and determine the antifungal efficacy of garlic EO and its major components, diallyl trisulfide and its nanoemulsions against wood-rotting fungi, Trametes hirsuta and Laetiporus sulphureus. GC-MS analysis revealed that the major constituents of garlic EO were diallyl trisulfide (39.79%), diallyl disulfide (32.91%), and diallyl sulfide (7.02%). In antifungal activity, the IC₅₀ value of garlic EO against T. hirsuta and L. sulphureus were 137.3 and 44.6 μg/mL, respectively. Results from the antifungal tests demonstrated that the three major constituents were shown to have good antifungal activity, in which, diallyl trisulfide was the most effective against T. hirsuta and L. sulphureus, with the IC₅₀ values of 56.1 and 31.6 μg/mL, respectively. The diallyl trisulfide nanoemulsions showed high antifungal efficacy against the examined wood-rotting fungi, and as the amount of diallyl trisulfide in the lipid phase increases, the antifungal efficacy of the nanoemulsions increases. These results showed that the nanoemulsions and normal emulsion of diallyl trisulfide have potential to develop into a natural wood preservative.     

Synthesis,characterization and antimicrobial activity of a bidentate NS Schiff base of S-benzyl dithiocarbazate and its divalent complexes

The reaction of S-benzyl dithiocarbazate (SBDTC) with 2,4,5-trimethoxybenzaldehyde afforded a bidentate NS Schiff base 1 (benzyl-3-N-(2,4,5-trimethoxyphenylmethylenehydrazine carbodithioate), which on further reaction with M(II) (where M(II) = nickel(II), zinc(II), palladium(II) and copper(II)) in ethanol under reflux yielded bis-chelated inner complexes [ML₂] 2–5 with deprotonated L. The ligand and its complexes were characterized by physicochemical techniques, viz., molar conductance, magnetic susceptibility measurement, IR, NMR, UV–Vis and mass spectroscopic techniques. The crystal structures of 1 and 5 were also determined by single-crystal X-ray crystallography. The crystal structure analysis showed that the ligand exists in its thione tautomeric form. In the complexes, each of the two deprotonated ligands chelated the metal ions through the β-nitrogen and the thione sulfur forming five-membered rings. The copper(II) complex (5) exhibited a square-planar geometry, where the two N₂S₂ chromophores are arranged trans. All the compounds showed strong antibacterial activity against S.-β-hemolyticus, Klebsiella pneumoni, and Escherichia coli. The compounds also showed strong antifungal activity against Aspergillus fumigatus, Aspergillus niger, Aspergillus flavus, and Candida albicans with the exception of the palladium(II) complex (4) which showed no activity, while all the compounds showed no activity against Fusarium vasinfectum.