Recent progress in the biochemistry of plant steroids other than sterols (Saponins, glycoalkaloids, pregnane derivatives, cardiac glycosides, and sex hormones)

Abstract

Recent studies concerning the biosynthesis, metabolism, and possible functions of steroids other than sterols in plants are reviewed and discussed. These studies embrace the saponins, glycoalkaloids, pregnane derivatives, cardiac glycosides, as well as their aglycones, and the sex hormones.

Lipid Biochemistry of Fungi and Other Organisms

“…Sterols are also required for optimum activity of certain enzymes, such as ATPase (Cobon and Haslam, 1973). Sterols are also precursors to steroids in higher plants (Heftmann, 1974) and hormones such as antheridiol in fungi (Barksdale, 1969).…”

Astonishing diversity of natural surfactants: 6. Biologically active marine and terrestrial alkaloid glycosides

“…Steroidal glycoalkaloids (SGA) have been found in several vegetables: potatoes (Solanum tuberosum), tomatoes (Lycopersicon esculentum), sugar beets (Beta vulgaris) and fruits: apples (genus Malus), cherries (genus Prunus) and red bell peppers (Capsicum annuum), but mainly in the plants of the Nightshade family, particularly the potato-an everyday food for many people for more than 2000 years (198)(199)(200)(201)(202). Potatoes are an essential component of the diet of many humans and animals and are thus a potential source of food poisoning (199,202).…”

“…Glycoalkaloids are plant steroids with a carbohydrate side chain attached to the 3-OH position, e.g., α-solanine and α-chaconine from potatoes, α-tomatine and dehydrotomatine from tomatoes (199,200,209). Recent research has found that SGA are responsible for increasing the risk of brain, breast, lung and thyroid cancer (198,(205)(206)(207)(208). Glycoalkalois are toxic to humans; the lethal dose is 3-6 mg per kg of body mass.…”

Glycosylation of Heterosides (Glycosides)

“…The biochemistry of the glucosylated form, which seems to be restricted to the Solanaceae, was first studied by HEFTMANN (1967). Solasodine, a C-27 nitrogenous steroid found in Solanum laciniatum is closely related to the spirostanol, diosgenin, and to similar C-27 steroidal sapogenins, which are frequently found in alkaloid-containing species within Solanum.…”