Showing papers on "Strychnos potatorum published in 1997"

Les strychnos africains et leurs alcaloïdes

Abstract: In the Greek Antiquity, the term strychnos was first coined to describe various toxic Solanacae. Nowadays, the genus Strychnos created by Linnaeus in 1753 is the numerically most important genus from the Loganiaceae family and comprises 196 species growing in the warm regions of Asia (58 species), America (64) and Africa (75). Species on the three continents are almost totally segregated. Only Strychnos potatorum is common to Asia and Africa. The toxicity of Strychnos was empirically well-known from time immemorial. Inhabitants of South-Eastern Asia and India had an ancestral knowledge of Strychnos nux vomica, whose deadly poisonous seeds were later imported and marketed in Europe to kill rodents and small predators. Concentrated extracts from Amazonian Strychnos, known as curates, are also remarkable hunting poisons, used by South American Indians. Accordingly, modern scientific investigations of Strychnos and their alkaloids started with Asian or American species used as traditionnal poisons. Strychnine was the first alkaloid found in Strychnos. It was isolated from Asian S. nux vomica in 1818, but its structure was fully elucidated only in the 1950s. Meanwhile, various curarizing alkaloids from American Strychnos were identified. Based on these early results, Strychnos alkaloids were initially classified according to their geographical origin. Asian Strychnos were assumed to contain strychnine and related compounds, whereas curarizing ammonium salts were associated with American Strychnos. African species were assimilated to their Asian counterparts and deemed of less interest. During the last three decades, however, systematic screening of African Strychnos has revealed the presence of numerous, varied alkaloids in these plants and demonstrated that the correlation between geographical distribution and alkaloid content was erroneous. Presently, 47 African species have been investigated and their alkaloids analyzed, significantly more than Asian and American materials (about 10 and 20 species, respectively). In this review, we present the alkaloids isolated so far from African Strychnos. 309 structures are listed and sorted according to their molecular weight, the most useful index key in modern research based on mass spectrometry.

Studies on the metal binding properties of the seeds of Strychos potatorum linn

Abstract: The seed of irmali tree Strychnos potatorum linn which grows wild in the Vindhyan and southern region of India are lenticular in shape and have previously been studied for their coagulation properties in clarifying turbidwater. This property was attributed to the presence of anionic polyelectrolytes having -COOH and free -OH surface groups that are present in the seed protein. However, the metal binding property of these seeds is of recent interest where some bench scale experiments were conducted at NML in order to establish the binding of metal ions from dilute HCl solutions. The seeds collected from the trees of S. potatorum Linn were ground to 0.5 mm size for experimentation purpose. The binding of different transition metals from aqueous solutions by these seeds was studied for Au (I), Ag (I), Cu (I), Cu (II), Co (II), Ni (II), Pb(II), Zn (II), Fe(II) and Fe (III) by shaking 1.0 g of the powdered seed in a 5% v/v HCl solution containing 50.0 ppm 1.0 ppm of the respective metal ion in a 50 ml solution for 5 min. The filtrate obtained after each experiment was analyzed for the respective metal ions and the results obtained are Au (I)=40.80 ppm; Ag (I)=41.10 ppm; Cu (I) =38.00 ppm; Zn (II) = 41.70 ppm; Fe (II) = 42.10 ppm and Fe (III) = 38.20 ppm. On an average the seeds binds 0.5 mg of the respective metals per 1.0 g of the seed. These seeds were fractionated into three different fractions, namely, fraction A, fraction B and fraction C using solvent extraction, distillation and centrifuging techniques in order to investigate what fraction of the seed is responsible in metal ion binding, and the weight percentages of each fraction were found to be 65%, 5% and 30%, respectively. Fraction A is mostly comprising of carbohydrates and some protein, whereas, fraction C is pure protein. Fractions A and C are found to be equally responsible for the binding of metals.