A large group of about 250, steroidal alkaloids possess a typical cyclopentanoperhydrophenanthrene nucleus. Many of them occur as esters of acids like acetic, angelic, butyric and vanillic. Most of the solanaceous steroidal alkaloids remain as glycosides and thereby resemble saponins. They have a limited distribution and are practically confined to families Liliaceae, Ranunculace, Buxaceae, Apocynaceae and Solanaceae.
Veratrum viride Aiton (Liliaceae)
Hellebore
This stout rhizomatous perennial, indigenous to the United States, possesses short thick rootstocks and dimorphic leaves, the lower ones being large and oval and upper ones small and narrow. The yellowish green flowers are borne on panicles and the capsular fruit contains numerous seeds.
Rhizome contains a large number of alkaloids (more than 20) which are grouped into two categories: (1) jerveratrum alkaloids, and (2) ceveratrum alkaloids. Jerveratrum alkaloids contain 1-3 oxygen atoms, occurring in the plant both as free alkamines and as glycosides and are similar to saponins in possessing haemolytic properties. Examples are jervine, veratramine (free alkamines), pseudojervine (jervine + glucose) and veratrosine (veratramine + glucose). Ceveratrum alkaloids are highly hydroxylated, containing 6-9 oxygen atoms and occur as free and/or esters with two or more acids. e.g. germine & protoverine (free alkamines), germinitrine (germine + acetic acid + tiglic acid + angelic acid), protoveratrine A (protovertine + 2 ¥ acetic acid + d-a-methyl butyric acid + a-oxy-a-methyl butyric acid).
These alkaloids, in mild doses, are employed as hypotensives, cardiac depressants and sedatives. They also exhibit a strong insecticidal action.
Holarrhena pubescens Wall. (Apocynaceae)
Syn. H. antidysenterica DC.
Kurchi, Holarrhena
Kurchi is a small tree with broadly elliptic leaves, white flowers (corona absent) in terminal corymbose cymes and a pair of long cylindric (often dotted with white spots) follicles enclosing numerous linear-oblong seeds tipped with a spreading deciduous corona of brown hairs. This is a native of India.
The bark of this tree contains steroidal alkaloids (upto 2.5%) such as conessine (upto 0.2%), 7-a-hydroxy conessine, holonamine, dihydroisoconessimine, 3-aminoconan-5-ene and kurcholessine. Other alka- loids reported are regholarrhenine A-F, pubescine, norholadiene, pubescimine, kurchinin, kurchinine, etc. The root bark yields holacetine. Leaves contain alkaloids such as kurchiphylline, kurchiphyllamine, kurchaline, holadysine and holadysamine; aminoglycosteroids like holantosines A,B,C & D and holarosine A and aminodeoxyglycosteroids holarosine B,E and F, flavonoids such as kaempferol and quercetin and phenolic acids (p-coumaric, vanillic, syringic, a-resorcylic and p-hydroxy benzoic acids). The seeds also contain a good amount of conessine, (Bhutani et al. 1990; Siddiqui et al. 1994; Daniel and Sabnis, 1978).
Bark and seeds are used in dropsy and dysentery (conessine is the antidysenteric principle), stomach disorders, abdominal and glandular tumours. Fruits are anticancerous and hypoglycemic and used to regulate menstruation.
Solanum americanum Linn. (Solanaceae)
Syn. S. incertum Dunal
S. nigrum Linn.
Kakmachi/Makoi
This is an erect herbaceous annual, with a much-branched slender glabrous stem, ovate/lanceolate leaves, small white flowers in clusters of 3-5 arising from internodal regions, and globose purplish black/red yellow berries containing many discoid seeds enveloped by an acidic pulp. Kakmachi occurs as a weed throughout India.
The whole plant, especially fruits, is used as the drug. All parts of the plant contain steroidal alkaloids of which solanine and solasodine glycosides are the major components (Sharma et al. 1983). Also present are uttroside A & B and uttronin A (spirostanol and furostanol glycosides), and sapogenins such as tigogenin and disogenin (Varshney and Dube, 1970). The leaves yield glycosides of quercetin (Nawwar et al. 1989).
The plant, especially the fruits, is used as an expectorant, antiinflammatory and diuretic. The plant extract exhibits hepatoprotective and antitumour properties.
Solanum surattense Burm. f. (Euphorbiaceae)
Syn. S. xanthocarpum Schrad & Wendl.
Kantakari
This is a diffuse herb with a prickly stem, leaves and calyx. The root is cylindrical and the leaves, ovate-oblong and pinnately 7-10 lobed. Flowers are purple in axillary cymes and the fruit is a globular yellow berry containing many smooth reniform seeds. Kantakari is a common weed throughout India.
The whole plant, which forms the drug, contains steroidal alkaloids such as solasodine (major component upto 0.2%), solamargine, b-solamargine and solasonine; sterols like cycloartenol, norcarpesterol, cholesterol and related compounds.
The drug is a well-known expectorant, antipyretic and useful in bronchial asthma and other respiratory diseases. Solasodine exhibits antispermatogenic, hypocholestrolaemic and antiatherosclerotic activities (Kanwar et al. 1990; Dixit et al. 1992).
Wrightia arborea Mabb. (Apocynaceae)
Syn. W. tomentosa Roem. & Shult.
Kutaja, Pala Indigo Plant
Kutaja is a small deciduous tree with abundant yellow latex, tomentose elliptic leaves, white fragrant flowers (with an orange corona of numerous fimbriate scales in 2-3 series) in lax terminal cymes and a pair of pendulous cylindrical grooved follicles rough with tubercles, containing slender seeds comose at the base. This tree is common in deciduous forests of India and nearby countries.
The bark of Kutaja contains alkaloids, conessine, holarrhine, kurchicine and conkurchine. Also present are b-sitosterol, lupeol and a-amyrin. The seeds yield an oil similar to that of Holarrhena, while the leaves yield quercetin, kaempferol, iso-orientin, procyanidin and phenolic acids such as vanillic, syringic, p-OH-benzoic and sinapic acids (Daniel and Sabnis, 1978) The root bark and seeds, often substituted for Holarrhena, are used for chronic diarrhoea and dysentery. Other uses include curing piles, haemorrhage, cardiac diseases, fever and colic. In Siddha system, this drug is used to cure psoriasis and other skin diseases. The leaves, used as a pot- herb, show analgesic, anti-inflammatory and antipyretic properties. The leaves also yield a blue dye used for dyeing clothes.
W. tinctoria R. Br is a related tree used as a substitute for Holarrhena. Its
bark is poor in alkaloids but contains b-amyrin, lupeol, b-sitosterol, a-amyrin, ursolic acid and oleanolic acid.
The other important plants yielding steroidal alkaloids are: (1) Funtumia
other species of Solanum yielding solasodine and related compounds. The alkaloids of Solanum are of great economic importance as starting materials in the synthesis of steroidal hormones. b-solamarine from S. dulcamera Linn. is tumour inhibitory and tomatine from Lycopersicum sp. is a good antibiotic.