Spectrophotometric determination of metronidazole and secnidazole in pharmaceutical preparations.

A rapid and sensitive spectrophotometric method is proposed for determination of metronidazole and secnidazole. The method depends on the reduction of metronidazole and secnidazole molecule with zinc dust and hydrochloric acid flowed by diazotization and coupling with 8-quinolinol to give red colored chromogens easily measured spectrophotometrically which has lambda(max) = 500 nm. The experimental conditions were optimized and Berr's law was obeyed over the applicable concentration ranges both techniques were applied successfully to a wide variety of pharmaceutical preparations.

Cynthichlorine: a bioactive alkaloid from the tunicate Cynthia savignyi.

From ether extracts of the tunicate Cynthia savignyi, collected in Morocco, a new alkaloid-cynthichlorine-has been isolated. The structure of cynthichlorine has been characterized by extensive 2D-NMR data. Cynthichlorine possesses antifungal activity against two tomato pathogenic fungi: Botrytis cinerea and Verticillium albo atrum and antibacterial activity against Agrobacterium radiobacter, Escherichia coli and Pseudomonas aeruginosa and cytotoxicity against Artemia salina larvae.

Investigation of bioactivity of extracts from Moroccan solitary tunicate Cynthia savignyi.

Extracts of the tunicate Cynthia savignyi from the Moroccan Atlantic sea have been investigated in five bioassays. The first is an antibacterial test against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Agrobacterium tumefaciens; the second is an antifungal test against three tomato pathogenic fungi, Botrytis cinerea, Fusarium oxysporum and Verticillium albo-atrum; the third is a test based to the ability to reduce DNA peak size in procedures using an HPLC system for detection of antitumour agents; the fourth is a toxicity test using larva of Artemia salina; and the last is an enzymatic inhibitory test against papain and trypsin. For all the bioassays, extracts of C.

Methoxybifurcarenone: an antifungal and antibacterial meroditerpenoid from the brown alga Cystoseira tamariscifolia.

A meroditerpenoid metabolite has been isolated from the brown alga Cystoseira tamariscifolia and characterized as methoxybifurcarenone, by spectral analysis. Methoxybifurcarenone possesses antifungal activity against three tomato pathogenic fungi: Botrytis cinerea, Fusarium oxysporum sp. mycopersici and Verticillium alboatrum and antibacterial activity against Agrobacterium tumefaciens and Escherichia coli.