Insulin from a plant source - by extraction of the fruit or seed cultures of Memordica charantia

摘要

Insulin is obtained by (a) extracting seed cultures or the fruit of memordica charantia with a mixt. of EtOH, H2O and H2SO4; (b) adjusting the pH of the extract to 1.5-2.0 by adding NH4OH or HCl; (c) adding cold EtOH and Et2O to ppte. the insulin; (d) crystallising the insulin in the presence of traces of Zn; and (e) purifying the product by thin-layer chromatography (TLC). The insulin is obtained from a cheap source without the slaughter of animals; the product does not induce antibody formation in humans, even when administered in high doses, and there is no risk of pathogenic viruses being transmitted. The fruit is pref. harvested in April, May and June. The seed cultures are pref. prepd. by notching the micropylar end of the seeds, culturing in 30 ml of a modified Murashige-Skoog (RT) medium contg. 1 ppm, 2,4-dichlorophenoxyacetic acid (2,4-D) and 1% agar for 36 months, transferring to a liq. RT medium contg. 1 ppm 2,4-D and shaking (60 min-1) at 26 degrees C with artificial illumination (1500-1800 Lux) for 4-6 months with frequent formation of subcultures. After extraction of the fruit or seed culture, the extract is pref. filtered, adjusted to pH 3.0 with NH4OH, mixed with cold EtOH and Et2O, kept at 0.5 degrees C for 12 hr, the ppte. crystd. with added Zn, the crystals dissolved in EtOH/NH4OH (1:2) and the soln. subjected to preparative TLC on silica gel with n-BuOH/H2O/HOAc (12:5:2).