Comparison of chromatographic systems for triterpenoids from Neem (Azadirachta indica) seeds

Novel Anti-inflammatory Activity of Epoxyazadiradione against Macrophage Migration Inhibitory Factor

“…The fractions containing pure nimbin (0.92 g; R f , 0.65) and salannin (4.42 g; R f , 0.51) were pooled and concentrated under reduced pressure. The spectral data for these compounds matched well with an earlier report (51).…”

“…Based on the spectral characteristics, the compound was identified as azadirachtin B (52). Further elution of the column with 1.5% methanol in dichloromethane yielded a fraction containing a compound that was identified as azadirachtin A (2.04 g; R f , 0.46) based on the spectral characteristics, which matched well with that of reported (51). The above dried crude extract (24 g) from neem fruit was then subjected to column chromatography (14 ϫ 6 cm) over silica gel (230 -400 mesh), and the compounds were eluted using a gradient mixture of methanol in dichloromethane.…”

Rapid separation of triterpenoids from Neem seed extracts

“…These triterpenoids are extracted either by first grinding the seeds with an alcohol, and then removing the oil by partitioning the alcoholic extract against a more lipophilic solvent (Butterworth and Morgan, 1972), or alternatively, grinding the seeds first with hexane or petrol to remove the oil, and then extracting the triterpenoids from the seed matrix using a more polar solvent (Schroeder and Nakanishi, 1987;Johnson and Morgan, 1997). Several methods have been employed for isolating azadirachtin and other triterpenoids from the extracts so obtained, including combinations of column and preparative layer chromatography (Butterworth and Morgan, 1972;Siddiqui et al, 1986;Yamasaki et al, 1986).…”

“…, an attapulgite clay (Butterworth and Morgan, 1972;Johnson and Morgan, 1997), used in gravity elution columns, has been the preferred material for column chromatography of these triterpenoids in our laboratory. It is less polar than alumina and silica, requires less polar solvents, and gives better recoveries of the purified triterpenoids.…”

Ratio of products formed on photo-oxidation of the neem triterpenoids nimbin and salannin

“…Nimbin and salannin were extracted from neem seeds of Indian origin, as described by the procedure of Johnson and Morgan. 15 Photo-oxidation of nimbin and salannin were carried out using the method described by Jarvis et al 11 Nimbin (36 mg, 0.067 mmol) was dissolved in benzene (45 ml), in a Schenk photo-chemical reactor. Oxygen was bubbled through the solution whilst it was being irradiated with UV light (Hanovia 1L, 90 W, Englehard, Slough, UK).…”