Inhibitive action of some plant extracts on the corrosion of steel in acidic media

The steam-distilled essential oil of Iranian black cumin seed (Nigella sativa L) was investigated for its composition and analgesic and antiinflammatory properties After oil analysis by GC/MS, 20 compounds were identified in the oil, obtained in 04% (v/w) yield Among them, para-cymene (373%) and thymoquinone (137%) were the major components Acetic acid-induced writhing, formalin and light tail flick tests were used for assessment of analgesic activity Antiinflammatory activity was evaluated using carrageenan-induced paw oedema in rats and croton oil-induced ear oedema in mice Black cumin seed essential oil (BCSEO) was found to produce a significant analgesic effect in acetic acid-induced writhing, formalin and light tail flick tests Naloxone, an opioid antagonist, could not reverse the analgesic effect observed in the formalin test Although oral administration of BCSEO at doses of 100, 200 and 400 micro L/kg did not exert a significant antiinflammatory effect in the carrageenan test, ip injection of the same doses significantly (p < 0001) inhibited carrageenan-induced paw oedema BCSEO at doses of 10 and 20 micro L/ear could also reduce croton oil-induced oedema It seems that mechanism(s) other than opioid receptors is (are) involved in the analgesic effect of BCSEO since naloxone could not reverse this effect Both systemic and local administration of BCSEO showed antiinflammatory activity Thymoquinone, as one of the major components of BCSEO, probably has an important role in these pharmacological effects

Black cumin seed essential oil, as a potent analgesic and antiinflammatory drug.

Nigella sativa L.: Chemical composition and physicochemical characteristics of lipid fraction

Infections with protozoan parasites are a major cause of disease and mortality in many tropical countries of the world. Diseases caused by species of the genera Trypanosoma (Human African Trypanosomiasis and Chagas Disease) and Leishmania (various forms of Leishmaniasis) are among the seventeen "Neglected Tropical Diseases" (NTDs) defined by the WHO. Furthermore, malaria (caused by various Plasmodium species) can be considered a neglected disease in certain countries and with regard to availability and affordability of the antimalarials. Living organisms, especially plants, provide an innumerable number of molecules with potential for the treatment of many serious diseases. The current review attempts to give an overview on the potential of such plant-derived natural products as antiprotozoal leads and/or drugs in the fight against NTDs. In part I, a general description of the diseases, the current state of therapy and need for new therapeuticals, assay methods and strategies applied in the search for new plant derived natural products against these diseases and an overview on natural products of terpenoid origin with antiprotozoal potential were given. The present part II compiles the current knowledge on natural products with antiprotozoal activity that are derived from the shikimate pathway (lignans, coumarins, caffeic acid derivatives), quinones of various structural classes, compounds formed via the polyketide pathways (flavonoids and related compounds, chromenes and related benzopyrans and benzofurans, xanthones, acetogenins from Annonaceae and polyacetylenes) as well as the diverse classes of alkaloids. In total, both parts compile the literature on almost 900 different plant-derived natural products and their activity data, taken from over 800 references. These data, as the result of enormous efforts of numerous research groups world-wide, illustrate that plant secondary metabolites represent an immensely rich source of chemical diversity with an extremely high potential to yield a wealth of lead structures towards new therapies for NTDs. Only a small percentage, however, of the roughly 200,000 plant species on earth have been studied chemically and only a small percentage of these plants or their constituents has been investigated for antiprotozoal activity. The repository of plant-derived natural products hence deserves to be investigated even more intensely than it has been up to present.

The Potential of Secondary Metabolites from Plants as Drugs or Leads Against Protozoan Neglected Diseases – Part I

Anticonvulsant effects of thymoquinone, the major constituent of Nigella sativa seeds, in mice.

Seed yield, yield components, oil content and essential oil content and composition of Nigella sativa L. and Nigella damascena L.

The seed oils of three accessions of Nigella sativa and N. damascena, sown on different dates, were obtained by Likens-Nickerson hydrodistillation and analyzed by GC/MS. The main components of N. sativa oil were p-cymene (33.8 %) and thymol (26.8 %), with only small amounts of thymoquinone (3.8 %). N. damascena oil was characterized by almost 100% sesquiterpenes, of which β-elemene (73.2 %) represented about three-quarters of the total amount.

Essential Oils of Nigella sativa L. and Nigella damascena L. Seed

Local landraces of shallot from the Romagna region(Northern Italy) and North-western France, called ‘Scalogno di Romagna’ and ‘French grey’,respectively, have recently been evaluated for morphological,biochemical and molecular characters. These populations appeared very different from common shallots and onions, so were re-classified as Allium oschaninii O.Fedtsch., whereas almost no variability was observed within these types. Four ‘di Romagna’ and three French accessions were grown in Italy, and further evaluated for quality characters such asbulb colour and volatile oil content and composition. Colour was measured by means of a tristimulus colorimeter. Volatile oil was extracted by hydrodistillation and its components separated and identified by GC/MS. Colour parameters differentiated the‘di Romagna’ from the ‘French grey’accessions. Essential oil composition differed from what has been reported for most other Alliums, by a lower amount of1-propenyl- substituents. No individual oil component allowed a good differentiation of the two geographic origins.However, the French and ‘di Romagna’ accessions were perfectly separated by the discriminant analysis of oil composition.Minor 1-propenyl- components seemed more critical for discrimination. The shallot types examined seemed biochemically differentiatedfrom Allium cepa. Variation in the examined quality characters was detected both between the two provenances and among the accessions of common geographic origin.

Alessandro Moretti

Papers

Seed yield, yield components, oil content and essential oil content and composition of Nigella sativa L. and Nigella damascena L.

Essential Oils of Nigella sativa L. and Nigella damascena L. Seed

Evaluation of ‘di Romagna’ and ‘Frenchgrey’ shallots for quality characters connected to bulb colourand volatile oil content and composition