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The aim of this study was to investigate the antimycobacterial activity of the major daucane constituent, ferutinin (jaeschkeandiol p-hydroxybenzoate, 1), four of its natural analogues, its hydrolysis products, as well as methyl p-hydroxybenzoate (methylparaben) against Mycobacterium smegmatis, a rapidly growing surrogate of Mycobacterium tuberculosis. The agar dilution assay was utilised for an antimycobacterial evaluation of single compounds. A modified agar dilution assay, the checkerboard method, was utilised for evaluating the potentiating effect of 1 on different antitubercular drugs, namely isoniazid, ethionamide, rifampin and streptomycin. In the agar dilution assay, 1 exhibited higher potency (minimum inhibitory concentration [MIC] 10 µg mL-1) than streptomycin and rifampin (MIC 20 µg mL-1 for each). Of the natural analogues, 8,9-epoxyjaeschkeandiol p-hydroxybenzoate and 8,9-epoxyjaeschkeandiol benzoate exhibited marginal activity (MIC ≥ 40 and 80 µg mL-1, respectively). The checkerboard method showed that the combination of 1 with each antitubercular drug led to mutual enhancement of the antimycobacterial activity with isoniazid and ethionamide, while no such effect was observed with rifampin or streptomycin. Based on this study and earlier studies with Staphylococcus aureus, the major constituent 1 may be responsible for the major part of the antimicrobial activity of the root of Ferula hermonis. [ABSTRACT FROM AUTHOR]

For the first time, a fast, high-performance liquid chromatography (HPLC) method was developed and validated for the simultaneous determination of the new ultra-short hypnotic HIE-124 and its metabolite in mice serum. Each compound, together with carbamazepine (internal standard) was extracted from the serum matrix using liquid–liquid extraction (LLE). Chromatographic resolution of the analytes was performed on a Chromolith Speed Rod monolithic silica column (100 mm × 4.6 mm i.d.) under isocratic conditions using a mobile phase of 65 : 35 (v/v), 20 mM phosphate buffer (pH 7.0 adjusted with phosphoric acid)–acetonitrile. The elution of the analytes were monitored at 240 nm and conducted at ambient temperature. Because of high column efficiency the mobile phase was pumped at a flow rate of 2.5 mL min−1. The total run time of the assay was 2 min. The method was validated over the range of 60–2000 ng mL−1for HIE-124 and 200–1600 ng mL−1for the metabolite (r2= 0.99). The limit of detection (LOD) for HIE-124 and its metabolite were 20 ng mL−1and 65 ng mL−1, respectively. The proposed method was validated in compliance with ICH guidelines, in terms of accuracy, precision, limits of detection and quantitation and other aspects of analytical validation. The developed method could be used for the trace analyses of HIE-124 and its metabolite in serum and was finally used for the pharmacokinetic study investigation of HIE-124 in mice serum. [ABSTRACT FROM AUTHOR]

The enhancing effect of sub-inhibitory concentrations of eugenol and isoeugenol with isoniazid, 6-paradol and 6-shogaol was evaluated in two different strains, Mycobacterium smegmatis and Candida albicans, using the in vitro checkerboard method. With M. smegmatis, isoeugenol (at ½ MIC) was able to lower the MIC (minimum inhibitory concentration) of isoniazid and 6-paradol by 800 percent (10-->1.25 [mu]g/mL) and 400 percent (30-->7.5 [mu]g/mL), respectively. Against C. albicans, Isoeugenol (at ½ MIC) was also able to lower the MIC of 6-paradol by 1600 percent (60-->3.75 [mu]g/mL). Similar synergistic effects were not observed between isoeugenol and 6-shogaol. Eugenol failed to exhibit any of the synergistic effects of isoeugenol under the same experimental conditions. Isoeugenol is a promising enhancing agent for compounds with weak antimycobacterial and anticandidal activities. 6-Paradol may be a potential candidate for further combination studies due to its broader antimicrobial effect against both M. smegmatis and C. albicans. [ABSTRACT FROM AUTHOR]

The chemical composition of three essential oil samples (stored aerial parts, fresh aerial parts, and fresh flowering tops) of Commiphora opobalsamum L., obtained by hydrodistillation, was determined using GC-MS analysis. The identified constituents represented 69.5 to 84.4 percent of the total chemical compounds of the three samples. The major components were [alpha]-cadinol in the stored aerial parts, [alpha]-calacorene in the fresh aerial parts, and terpinen-4-ol in the fresh flowering tops. The essential oil from the fresh aerial parts exhibited antimicrobial activity against Bacillus subtilis, Staphylococcus aureus, Candida glabrata, C. krusei, Cryptococcus neoformans, and Mycobacterium intracellulare. The same oil sample was non-selectively cytotoxic to four tumor cell lines: SK-MEL, KB, BT549 and SK-OV3. Weak antioxidant activity of the oil from the fresh aerial sample was demonstrated in a DPPH free-radical scavenging assay. [ABSTRACT FROM AUTHOR]

The aerial part of Commiphora opobalsamum L. (Burseraceae) growing in Saudi Arabia was subjected to a phytopharmacological investigation in order to identify its major chemical constituents and to evaluate its extracts and isolated compounds in preliminary in vitro assays for antimicrobial, antimalarial, antitumor, anti-inflammatory (COX-2 inhibition), antioxidant and estrogenic activity. Six compounds were isolated and identified as the triterpenes friedelin, canophyllal, and oleanonic acid; the flavonols mearnsetin and quercetin; and syringic acid. The ethyl acetate extract was moderately active against Staphylococcus aureus, Pseudomonas aeruginosa, and Plasmodium falciparum; while the petroleum ether and chloroform extracts inhibited COX-2 at 5 and 10 µg mL-1, respectively. Of the isolated compounds, syringic acid showed moderate antimalarial, anticandidal, and antimycobacterial activity; while mearnsetin and quercetin exhibited antioxidant activity comparable to ascorbic acid and trolox. This is the first detailed phytochemical investigation of C. opobalsamum L. growing in Saudi Arabia and elsewhere. The isolated compounds are reported from this plant for the first time and their full 1H and 13C NMR assignments are included. [ABSTRACT FROM AUTHOR]

Although the traditional use of Ephedra ‘ma huang’ has been established for thousands of years, its resurgencein the US as a herbal dietary supplement is currently a matter of national controversy. At the heart of the debate are three important questions: (1) the identity and composition of Ephedra products with regard to ephedrine and related alkaloids; (2) the potential therapeutic utility of Ephedra supplements for weight loss or performance enhancement; and (3) potential health risks associated with such uses of Ephedra, particularly in sensitive individuals or in cases of intentional abuse for its stimulant properties. This review surveys the literature on Ephedra with regard to traditional uses, botany, chemistry, analytics, pharmacological effects and health risks. A brief discussion of the central issues in the current debate on the regulation of Ephedra in the United States is included as this is where most of the problems have occurred to date. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Clutia richardiana L. is a traditional medicinal herb with demonstrated hypoglycemic effects. An HPLC method (Luna® C18 column, gradient elution, UV detection at 220 nm) has been utilized to determine the levels of the major diterpenes of C. richardiana in extracts obtained by using three different solvents. Extraction with the organic solvents methanol and acetonitrile was more efficient than aqueous extraction with hot water, but nine markers could be detected equally in all extracts. The aqueous extract was non-toxic against a number of human cell lines, which is a promising indication for its use as a safe and effective antidiabetic herbal preparation. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The inhibitory activity of 34 natural products of various structural classes on hydroxyphenylpyruvate dioxygenase (HPPD), the target site for triketone herbicides, and the mode of interaction of selected natural products were investigated. Recombinant HPPD from arabidopsis is sensitive to several classes of natural compounds including, in decreasing order of sensitivity, triketones, benzoquinones, naphthoquinones and anthraquinones. The triketone natural products acted as competitive tight-binding inhibitors, whereas the benzoquinones and naphthoquinones did not appear to bind tightly to HPPD. While these natural products may not have optimal structural features required for in vivo herbicidal activity, the differences in their kinetic behavior suggest that novel classes of HPPD inhibitors may be developed based on their structural backbones. [Copyright &y& Elsevier]