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Challinor V.L.,University of Queensland | Chap S.,University of Queensland | Lehmann R.P.,Integria Healthcare | Bernhardt P.V.,University of Queensland | De Voss J.J.,University of Queensland
Journal of Natural Products | Year: 2013

We report the isolation and structure elucidation of a new cheilanthane sesterterpene from the roots of Aletris farinosa that possesses an unusual malonate half-ester functional group. The structure of 1 was determined via mass spectrometry and 1D and 2D NMR spectroscopy, while its absolute configuration was determined via X-ray crystallographic analysis performed on its methyl ester derivative 2. © 2013 The American Chemical Society and American Society of Pharmacognosy.

Kasrati A.,Cadi Ayyad University | Alaoui Jamali C.,Cadi Ayyad University | Fadli M.,Cadi Ayyad University | Bekkouche K.,Cadi Ayyad University | And 5 more authors.
Industrial Crops and Products | Year: 2014

Thymus saturejoides is a perennial shrub widely distributed in the arid and semi arid parts of the Moroccan mountains. Essential oils (EOs) of this species are used extensively in food and pharmaceutical industries because of their wide biological and pharmacological properties. To our knowledge, no data are available on the antibacterial and antioxidant activities of T. saturejoides EOs in relation to the chemical variability of the species. Also, the potential synergistic interaction of EOs from this species as natural antimicrobial agent with conventional antibiotics against food-borne bacteria has not been investigated. Thus, the aim of the present study was to determine the volatile oil constituents of EOs from three wild Moroccan T. saturejoides populations collected from Northwest-Southeast of Morocco (June, 2011). Antioxidant activity and their antibacterial potency (singly and in combination with cefixime) against selected food-borne bacteria was then determined. Gas chromatography-mass spectrometry (GC-MS) analysis revealed 30 compounds, representing 98.6 to 99.5% of the total oils. The major constituents identified were carvacrol (45.3%), p-cymene (8.9%), linalool (8.4%), and borneol (7.5%) in oil from the Er-Rich population (arid site); carvacrol (26.5%), borneol (20.1%), camphene (8.0%), and γ-terpinene (5.6%) in oil from Ourika population (medium arid site) and carvacrol (25.3%), borneol (19.7%), camphene (7.6%), and p-cymene (6.6%) in oil from Taws population (less arid site). Essential oil obtained from Er-Rich population showed the highest antioxidant activity as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging ability, reductive potential, and β-carotene/linoleic acid assays with IC50 values of 44.54±0.92μg/mL, 22.90±0.16μg/mL and 19.17±0.01μg/mL, respectively. Antibacterial tests showed that the oils from this species had a high inhibitory activity against tested bacteria, with the exception of Pseudomonas aeruginosa. The most potent activity was observed with oil obtained from the Er-Rich population with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 0.14 to 0.55mg/mL and 0.28 to 0.55mg/mL, respectively. Out of 21 combinations tested between EOs and cefixime, 67% showed total synergism, 19% had partial synergistic interaction and 14% showed no effect. Oil from the Er-Rich population exhibited the highest synergistic effect with antibiotic (FIC index values of 0.29 to 0.5). The synergy displayed by this combination of EO and cefixime may be of potential benefit for control of food-related bacteria, consequently permitting the use of lower doses of standard antibiotics. © 2014 Elsevier B.V.

Banbury L.K.,Southern Cross University of Australia | Shou Q.,Southern Cross University of Australia | Renshaw D.E.,Southern Cross University of Australia | Lambley E.H.,Southern Cross University of Australia | And 3 more authors.
Journal of Ethnopharmacology | Year: 2015

Ethnopharmacological relevance Australian Aboriginal people used crushed leaves of Geijera parviflora Lindl. both internally and externally for pain relief, including for toothache (Cribb and Cribb, 1981). This study tested the hypothesis that this traditional use might be at least in part explained by the presence of compounds with anti-inflammatory activity. Materials and methods A crude extract (95% EtOH) was prepared from powdered dried leaves. From the CH3Cl fraction of this extract compounds were isolated by bioassay-guided fractionation and tested for: (1) cytotoxicity in RAW 264.7 murine leukemic monocyte-macrophages, (2) prostaglandin E2 (PGE2) inhibitory activity in 3T3 Swiss albino mouse embryonic fibroblast cells, as well as (3) nitric oxide (NO) and (4) tumour necrosis factor alpha (TNFα) inhibitory activity in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Isolated compounds were also tested for (5) antibacterial activity against a panel of Gram-positive (Staphylococcus aureus ATCC 29213 and ATCC 25923, Staphylococcus epidermidis ATCC 35984, biofilm-forming) and Gram-negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853) strains by broth microdilution. Results Eleven compounds were isolated, including one new flavone and one new natural product, with a further four compounds reported from this species for the first time. Some of the compounds showed good anti-inflammatory activity in vitro. In particular, flindersine (1) and N-(acetoxymethyl) flindersine (3) inhibited PGE2 release with IC50 values of 5.0 μM and 4.9 μM, respectively, without any significant cytotoxicity. Several other compounds showed moderate inhibition of NO (5, 6, 7) and TNF-α (6), with IC50 in the low micromolar range; however much of this apparent activity could be accounted for by the cytotoxicity of these compounds. None of the compounds showed anti-bacterial activity. Conclusions The inhibition of PGE2, an important mediator of inflammation and pain, by flindersine and a derivative thereof, along with the moderate anti-inflammatory activity shown by several other compounds isolated from Geijera parviflora leaf extract, support the traditional use of this plant for pain relief by Australian Aboriginal people. © 2015 Elsevier Ireland Ltd. All rights reserved.

Challinor V.L.,University of Queensland | Stuthe J.M.U.,University of Queensland | Parsons P.G.,Queensland Institute of Medical Research | Lambert L.K.,University of Queensland | And 3 more authors.
Journal of Natural Products | Year: 2012

Figure Persented: Phytochemical investigation of Chamaelirium luteum ("false unicorn") resulted in the isolation of 15 steroidal glycosides. Twelve of these (1, 2, 4-9, 11-13, and 15) are apparently unique to this species, and eight of these (6-9, 11-13, and 15) are previously unreported compounds; one (15) possesses a new steroidal aglycone. In addition, the absolute configuration of (23R,24S)-chiograsterol A (10) was defined, and its full spectroscopic characterization is reported for the first time. The structures and configurations of the saponins were determined using a combination of multistage mass spectrometry (MSn), 1D and 2D NMR experiments, and chemical degradation. The antiproliferative activity of nine compounds obtained in the present work, and eight related compounds generated in previous work, was compared in six human tumor cell lines, with aglycones 3 and 10 and related derivatives 16, 17, 19, and 20 all displaying significant antiproliferative activity. © 2012 The American Chemical Society and American Society of Pharmacognosy.

Challinor V.L.,University of Queensland | Parsons P.G.,Queensland Institute of Medical Research | Chap S.,University of Queensland | White E.F.,University of Queensland | And 3 more authors.
Steroids | Year: 2012

Phytochemical characterization of a commercial herb sample supplied as Smilax ornata Lem. (sarsaparilla) led to the isolation of five steroidal saponins, including two new furostanol saponins sarsaparilloside B (1) and sarsaparilloside C (2), whose structures were elucidated via a combination of multistage mass spectrometry (MS n), 1D and 2D NMR experiments, and chemical degradation. The previously unreported spectroscopic characterization of sarsaparilloside (3), Δ 20(22)-sarsaparilloside (4), and parillin (5) is also provided. The antiproliferative activity of the isolated saponins was compared in six human cell lines derived from different tumor types and one of the structures (2) was particularly active against the HT29 colon tumor cell line. © 2011 Elsevier Inc. All rights reserved.

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