Datura – species Datura L.


In medical terms, the most important species belong to the sections Dutra and Stramonium. These sections differ in bolls and seeds.

Species of the Stramonium section have upright capsules, black seeds. The alkaloid hyoscyamine predominates; scopolamine is non-cordinal abundance. Species of the Dutra section have drooping bolls, yellow seeds. The dominant alkaloid is scopolamine.

Types of section Stramonium. This includes two types:

D. stramonium L. – common dope – a species common to the southern and middle zones of Europe and Asia, North and Tropical Africa. Cultivated in many European countries, Japan, China.

An annual plant with forked-branched, bare stems. Leaves are petiolate, in pairs close together, up to 25 cm long, ovate, pointed, unevenly coarsely toothed, almost glabrous. Flowers up to 10 cm long, solitary, sitting in the forks of stems and branches. Calyx half as long as corolla, tubular, drooping; corolla white, tubular-funnel-shaped with a long narrow tube and with a folded 5-lobed limb. The box is seated with numerous thick and hard spines. Leaves (Folium Stramonii), which accumulate 0.25-0.4% alkaloids, are part of most anti-asthma cigarettes and fees.

D. tatula L. – purple dope . Some authors regard it as a variety of D. stramonium L. It is distributed in countries with a hot climate. Cultivated in Japan, China, USA.

Vigorous, strongly branched annual herbaceous plant. Stem purple; petioles, leaf veins and partially calyx are purple. The leaf blade is more dissected, always deeply incised into large, pointed, in turn incised teeth. The base of the leaf is broadly wedge-shaped, sometimes slightly heart-shaped. Corolla bluish to blue-purple. Capsule ovoid, always strongly and evenly spiny; the upper spines do not differ in length from the lower ones. They grow along roads, on garbage heaps and wastelands.

Up to 0.65% alkaloids accumulate in flowering branches. The application is the same as that of ordinary dope.

Views of the Dutra section. These include perennials: D. innoxia Mill., D. metel L. and D. meteloides Dunn.

D. innoxia Mill. – dope is non-poisonous, Indian , grows in South and Central tropical America and other tropical states. Introduced into cultivation in India, South China, Egypt, Lebanon, Nigeria, USA (Florida), Mexico, Brazil, etc. Powerful herbaceous plant. The leaves are dense, shallow, serrated. The flowers are white, even larger than those of Datura, the calyx is densely pubescent. Capsule with long spines on long densely pubescent stalks.

All parts of the plant contain within 1% of the amount of alkaloids. The largest amount of scopolamine accumulates in immature pods (within 0.55%), which serve as the main industrial raw material for the production of scopolamine and atropine along the way.

D. metel L. – Datura broom . Distributed in tropical and subtropical Asia; grows wild in Africa and the Mediterranean. Cultivated in India, China.

Plant 80-100 cm tall, stem forked-branched, dark purple. The leaves are heart-shaped with a pointed apex, not often shallow within pasty, bluish-green, slightly pubescent. The flowers are white, with a pleasant smell. Corolla 18-20 cm long, open flower diameter 9-12 cm, corolla edge deeply dissected, calyx 10 cm long, green, swollen, not ribbed, with 3-5 long, uneven teeth. The capsule is spherical-flattened, almost naked at the apex, with short (up to 0.3 cm) needle-like spines at the base. The leaves, which accumulate the largest number of alkaloids (up to 0.5%), are the raw material for the production of scopolamine.

D. meteloides Dunn. – dope meteloid . Distributed in tropical and subtropical America; where it is cultivated. Light green plant without anthocyanins. The capsule is completely seated with numerous short (no more than 0.5 cm) awl-shaped spines. Otherwise, it is close to D. metel L.

Industrial source of scopolamine and atropine along the way. In culture (Ukraine, Russia, Armenia), the content of alkaloids reaches 1.9%.

The plant contains alkaloids with fused pyrrolidine and piperidine rings (derivatives of tropine, scopine and ecgonine).



These alkaloids are based on a system known as tropane, built from piperidine and pyrrolidine rings. The diversity of these alkaloids depends on which amino alcohol was formed in the process of biosynthesis from tropane (tropine, scopine or ecgonine) and with what organic acids these amino alcohols subsequently formed esters.

Alkaloids, which are derivatives of the amino alcohols tropine or scopine, accumulate in plants of the genera of the nightshade family – belladonna, henbane, dope, scopolia, duboisia, mandrake, physochlein.

Tropine in nightshades is esterified with tropic acid to form the alkaloid hyoscyamine. Hyoscyamine is found in plants in the form of a left-handed isomer and in this state passes into galenic products; in the factory isolation of the alkaloid from plants, it is traditionally obtained its inactive racemate – atropine in the form of a salt – Atropini sulfas.



C-copyne also forms an ester with tropic acid. This alkaloid is called scopolamine or hyoscine. Natural scopolamine is also a levorotatory compound. Its racemate, scopolamine, is called atroscin.

Other tropane derivatives, found in the same plants in small quantities, as well as liquid and volatile pyridine derivatives, often associated with tropane alkaloids, are of no practical importance.

The total content of alkaloids in different Solanaceae is very different and varies within 0.04-3%. In the same species, the amount of alkaloids is different in different organs of the plant and, moreover, varies depending on the phase of vegetation and environmental conditions. Usually, the sum of alkaloids in all Solanaceae species includes both main alkaloids, but in all possible proportions, one of them prevails. This circumstance determines the different use of certain types of nightshade.

The action of atropine and thioscyamine is antispasmodic, dilating the pupil, relaxing smooth muscles, analgesic, limiting the secretion of sweat glands, relieving the symptoms of motion sickness, and stimulating the central nervous system. Scopolamine calms the central nervous system; otherwise, its action is similar to that of atropine.


Alkaloids are called natural nitrogen-containing compounds of the main character, formed in plants. Groups of proteinogenic amines (for example, tyramine) and betaines (stakhidrin, trigonelline, etc.) adjoin the alkaloids, which are considered as transitional compounds from the simplest nitrogen-containing compounds (methylamine, trimethylamines, etc.) to the alkaloids proper.

Of natural pharmacologically active substances, alkaloids are the main group from which modern medicine draws the largest number of highly effective drugs.

According to world literature, by the end of the past decade, the number of alkaloids isolated from the higher plants of the Earth’s flora exceeded 5000. According to modern concepts, alkaloid-bearing plants make up 10% of the entire world flora. The families Equisetaceae, Lycopodiaceae, Ephedraceae, Liliaceae, Amaryllidaceae, Dioscoreaceae, Chenopodiaceae, Nymphaeaceae, Ranunculaceae, Berberidaceae, Menispermaceae, Papaveraceae, Fabaceae, Rutaceae, Cactaceae, Punicaceae contain the largest number of alkaloid-bearing genera and species. Loganiaceae, Apocynaceae, Borraginaceae, Solanaceae, Rubiaceae.

Usually plants that are phylogenetically close contain alkaloids that are very similar in structure, thus forming a natural group of genera. For example, plants of the genera Atropa, Datura, Hyoscyamys, Scopolia, Physochlaina, Duboisia. Mandragora (all from the same Solananeae family) contain a well-defined group of tropane alkaloids. This far-reaching pattern, however, has exceptions that have not yet been explained. So, for example, caffeine is found in plants that are not systematically related to each other: tea (Theaceae), coffee (Rubiaceae), cocoa (Sterculiaceae), mate (Aquifoliaceae), guarana (Sapindaceae), erodium (Geraniaceae). Along with this, there are cases when their 2 very close systematically species, one is rich in alkaloids, and the other either does not contain them at all, or contains alkaloids of a different structure.

Alkaloids can be found throughout the plant, or they can be formed and accumulated only in one or more specific organs. The plant traditionally contains not one, but several alkaloids. In individual plants, there may be 20 or more of them (cinchona, hypnotic poppy, etc.), and they may be similar in structure or belong to different chemical groups. In the sum of alkaloids, 1–3 traditionally predominate quantitatively (the main alkaloids). In plants, alkaloids are dissolved in the cell sap of the main parenchyma, phloem, and other tissues in the form of salts, mainly organic acids (malic, succinic, citric, oxalic, fumaric, quinic, etc.); of mineral acids, phosphoric acid is more often involved.

The quantitative content of alkaloids is, in principle, a species characteristic, and it varies over a very wide range. For example, in black henbane they are only 0.05-0.1%, and up to 15% accumulate in the cinchona bark. In the process of ontogenetic development of plants, their alkaloid content undergoes quantitative and sometimes qualitative changes, and each species has its own regularities.

The content of alkaloids in plants is influenced by their geographical location and various factors (air and soil temperature, precipitation, duration and intensity of sunlight, shading, height above sea level, etc.), as well as human impact in the case of transferring the plant to cultivation or its acclimatization. The largest number of alkaloid-bearing species, moreover, with a high content of alkaloids, is common in subtropical and tropical states with a humid climate. Alkaloids of different structure are confined to certain latitudes, and in connection with this, their pharmacological activity changes.

There is no consensus on the biological role and causes of the formation of alkaloids in plants. The main hypotheses proposed at different times interpret alkaloids as: 1) waste products of the vital activity of a plant organism; 2) spare substances; 3) protective substances; 4) active substances necessary for biosynthesis. The latter hypothesis is currently considered by most scientists to be the most general one, which, however, does not exclude other biological functions of alkaloids.

The exceptional diversity in the structure of alkaloid molecules does not allow us to imagine a single way of their formation in plants. Their biosynthesis proceeds according to specific schemes with the most complex chemical transformations (ring opening and closing, oxidation, deamination, ring condensation, etc.) through many intermediate products. Some alkaloids begin biogenesis from amino acids, others from acetic acid (in other words, from carbohydrates).

The modern classification of alkaloids is based on the nature of the heterocycles included in their molecules, with the release into a separate group of alkaloids with an aliphatic structure and with nitrogen in the side chain.

1. Alkaloids with an aliphatic structure or with nitrogen in the side chain;

2. Pyrrolizidine alkaloids.

3. Piperidine and pyridine alkaloids.

4. Alkaloids with condensed and pyrrolidone and piperidine rings.

5. Quinoline alkaloids.

6. Quinazoline alkaloids.

7. Isoquinoline alkaloids.

8. Indole alkaloids.

9. Alkaloid of the imidazole group.

10. Purine alkaloids.

11. Diterpene alkaloids.

12. Steroid alkaloids (glycoalkaloids).

13. Alkaloids of unknown structure.

In conclusion of this brief review, it should be pointed out that most alkaloids are highly active substances with selective pharmacological action. The selectivity of the action of alkaloids determines their widespread use for medicinal purposes. The main forms are extraction products (tinctures, extracts, novogalenic preparations, etc.) and pure alkaloids isolated from plants, converted into soluble salts of certain inorganic and organic acids.

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