Search

A saturated solution of SbCl3 in 60% HClO4 was used to detect steroids in plant tissue, using (a) cut sections of fresh material (b) dried and powdered material and (c) dried aqueous ethanolic extracts of microquantities of tissues. The utility of this reagent as a microchemical test for diosgenin and yamogenin has been established by application to 55 plant specimens from 35 species in 12 families, including plant parts which hold steroidal sapogenin (spirostans) as well as those that do not. The presence or absence of spirostans in the plant parts was confirmed by infrared analysis after processing the material on a macro scale. Colours obtained with the reagent and pure sapogenins, some of their common derivatives and their glycosides are given for reference.

A new, sensitive LC/MS/MS method was developed for the quantification of ruscogenin and neoruscogenin in hydrolyzed extracts from Ruscus aculeatus L. (Liliaceae). The two sapogenins were separated on a Zorbax SB-C18 column under isocratic conditions. The detection was performed in the multiple reaction monitoring mode using an ion trap mass spectrometer with an electrospray ionization source operated in positive ionization mode. For the quantification of the ruscogenin and neoruscogenin, calibration curves were constructed over the range of 21000 ng/mL. This is the first reported LC/MS/MS method for the simultaneous analysis of ruscogenin and neoruscogenin, and it showed superior sensitivity when compared with other assays described in the literature. The method has been successfully applied to quantify the two sapogenins in aerial (phylloclades) and underground parts (rhizomes, roots) of Ruscus aculeatus L.

Carrot (Daucus carota L.) cell suspensions were treated with a spirostanol saponin from Yucca. This saponin is an elicitor of callose synthesis. Irrespectively of the mode of action of spirostanol on the callose synthase activity itself, the spirostanol-induced callose synthesis in carrot is not preceded by changes in membrane potential, cytosolic free calcium or cytosolic pH. The inability of modulators of cytosolic free calcium content (verapamil, nifedipine and Br-A23187), EGTA and a proton pump inhibitor (vandate) to inhibit or induce callose formation is consistent with a calcium- and pH-independent mechanism for callose deposition.

A new phenylpropanoid ester of a pyrroline derivative and two new steroidal saponins were isolated from the fresh bulbs of Lilium martagon, along with several previously known compounds. The structures of the new compounds were determined by spectroscopic data, hydrolysis, and by comparison with spectral data of known compounds to be (−)-5-hydroxy-3-methyl-3-pyrrolin-2-one 5-O-(6-O-p- coumaroyl -β- d -glucopyranoside ) , (25S)-spirost-5-ene-3β,17α,27-triol 3-O-{O-β- d -glucopyranosyl -(1 → 2)-O-β- d -glucopyranosyl -(1 → 4)-β- d -glucopyranoside } and (25S)-5α-spirostane-3β,17α,27-triol 3-O-{O-β- d -glucopyranosyl -(1 → 2)-O-β- d -glucopyranosyl -(1 → 4)-β- d -glucopyranoside } , respectively. Lilium martagon crosses well with L. hansonii to produce a valuable garden hybrid lily. In this study, the secondary metabolites of L. martagon were revealed to be closely related to those of L. hansonii, giving a good example of the correlation between the secondary metabolites and cross-compatibility.

Four species of Dioscorea were grown as callus and suspension tissue cultures on revised Murashige and Skoog's tobacco medium and contained diosgenin.

Eine einfache Synthese von 18-Nor-Pregnan-Derivaten durch die Decarboxylierung eines 12-Keto-18-Saure-Lactons (→-20) wird beschrieben.

(24R)-[24-3H]- and (24S)-[24-3H]-cholesterols are transformed into tigogenin [(25R)-5α-spirostan-3β-ol] in Digitalis lanata without involvement of the hydrogen atoms at C-24; this confirms that the reduction of the Δ24-precursor of cholesterol is a ‘trans’ process.

A previously described routine procedure involving the use of a silica gel column in determining diosgenin and yamogenin has been improved by using water-containing solvents. The advantages are that there is less variation between duplicate results, that each column can be used at least five times and that component bands are eluted in predictable volumes of solvents. An apparatus and solvent sequence is described that allows twelve columns to be developed simultaneously.The method has been successfully applied to crude extracts from Dioscorea deltoidea tuber and to oily crude extracts from the seeds of Trigonella foenumgraecum(fenugreek) and Balanites aegyptiaca. The over-all error of the procedure, including sampling, extraction and infrared spectrophotometric determination for duplicate analyses of 2·5-g samples of the fenugreek seed used, expressed as a 95 per cent. confidence interval of the mean sapogenin value, was 1·04 ± 0·025 per cent. for diosgenin plus yamogenin, 0·64 ± 0·019 per cent. for diosgenin and 0·40 ± 0·023 per cent. for yamogenin.As the method does not permit the separation of tigogenin from diosgenin nor that of neotigogenin from yamogenin, the results indicate maximum yields for diosgenin and yamogenin in fenugreek seed. The results exclude sterols, steryl esters, dihydroxysapogenins and spirostadienes.

A simple method for determining diosgenin in Dioscorea tubers involving extraction and gas-liquid chromatography has been developed and used in our laboratory for the last 6 years. A small amount (600 mg) of the ground, dried tuber is hydrolysed by refluxing it for 4 hours with a 1 + 1 mixture of 3 N aqueous hydrochloric acid solution and xylene, after adding a suitable internal standard. After centrifuging the mixture, a portion of the xylene layer is injected on to the gas-chromatographic column, without any further manipulations. Hydrolysis conditions were examined to ensure that the release of diosgenin was complete and its degradation at a minimum. The proposed method enables pennogenin to be separated from diosgenin, but yamogenin is poorly resolved. The relative standard deviation for the determination of diosgenin was about 1·5 per cent. Good agreement with a gravimetric method was found.