Name: Pyretra daisies
Daisies
Dalmatian chamomile – Pyrethrum cinerarifolliiim Trev,;
Caucasian chamomile -P . roseum (Adams) MB;
Persian chamomile – P. caraeum M. V.
P. cinerariaetoltum is distributed in the Balkans and the Adriatic islands. Cultivated on all continents of the world (India, Japan, Morocco, Algeria, Ethiopia, Kenya, Tanzania, USA, Argentina, Peru, Bolivia, Australia, USSR).
P. roseum and P. carneum grow in Turkey, Iran, the USSR (Northern Caucasus and Transcaucasia). Cultivated (except the USSR) in India, Iran, East Africa, Congo.
All three species are perennial herbaceous plants with numerous slightly branched, woody stems below. Rosette leaves numerous, large, long-petiolate, dissected, stem – short-petiolate. Baskets are large, single, apical.
P. cinerariaefolium has anthologies with white reed (up to 20) flowers; the leaves are ash-gray, doubly and triply pinnately dissected.
P. roseum has baskets with pink ligulate (up to 30) flowers; leaves bipinnate, secondary lobules linear.
P. carneum has anthracites with dark red ligulate (up to 30) flowers; pinnately dissected leaves, lobules lanceolate with sawtooth-dissected edges.
Medicinal raw materials are flower baskets (Flores Pyrethri insecticidi) collected in the phase of full flowering. The size of the dried baskets is 0.7-1.5 cm.
Insecticidal chamomile contains up to 0.4% essential oil and specific substances – pyrethrins and cynerins, the number of which reaches 1.2-1.8%. Pyrethrins and cynerins are derivatives of monocarboxylic chrysanthemum and pyrethric acids. These acids are monoterpenes, irrationally formed by two molecules of isoprene, with acidic components.
Pyrethrins are esters of chrysanthemic acid with the ketoalcohol pyretrolone (pyrethrin I) and pyrethrinic acid with the same ketoalcohol (pyrethrin I).
Cynerins (I and II) are esters of ketoalcohol cinerolone, respectively, with the indicated acids.
Preparations of pyrethral chamomiles (flower powders) and their white spirit extracts (flicid, etc.) are effective insecticidal preparations for combating granary pests and pests of vegetable and fruit crops. In veterinary medicine, these are anti-scabies and antihelminthic drugs. Harmless to humans, pets and plants.
The plant contains monocyclic terpenes.
PLANTS CONTAINING MONOCYCLIC TERPENE
Monocyclic terpenes are derivatives of methylisopropylcyclohexane with two (or one) double bonds. Double bonds can be both in the ring (terpenes, a-phellandrene) or one of them is in the isopropyl group (limonene) or at C 1 -C 7 ) b-phellandrene).
Of the oxygen derivatives, the most common are: alcohols – terpineol, menthol, ketones – menthone, piperitone, carvone, oxides – cineol.
Some monocyclic terpenes are often present in essential oils together with aliphatic terpenes (eg essential oils of many citrus fruits) or accompany bicyclic monoterpenes and sesquiterpenes (see below). For these reasons, the division of essential oil plants into groups of terpenes is somewhat arbitrary.
PLANTS CONTAINING ESSENTIAL OILS
Essential oils are natural fragrant substances that are highly volatile and cause the specific smell of plants. For this reason, also due to their “oily” consistency and “greasy” spot on paper, which soon disappears, they received such a peculiar name.
Essential oils are not individual substances. These are complex mixtures of organic substances, the composition and number of which are different for each type of essential oil plants and can serve as a chemotaxonomic feature. The main group of substances that make up the essential oils of many plants are terpenes (more precisely, monoterpenes) and seseviterpenes, that is, substances with an isoprenoid structure. However, in the essential oils of a number of plants, aromatic compounds may predominate, as well as numerous substances of the aliphatic series. There are plants with sulfur and nitrogen compounds in essential oils.
Essential oils in plants are mostly in a free state. However, some plants contain them in the form of glycosides and are released during enzymatic cleavage. Essential oils are formed in all parts of plants, but quantitatively they accumulate in them traditionally unequally.
They can be in a plant organism in a diffuse diffuse state (ie, emulsified or dissolved in cells) or accumulate, localize in special anatomical and morphological formations that are easily detected under a microscope. These excretory formations can be exogenous and endogenous.
Exogenous formations develop in the epidermal tissue and are:
– glandular “spots” – small-drop accumulations of essential oils immediately under the cuticle of the epidermis;
– glandular hairs – cylindrical epidermal outgrowths, consisting of a unicellular or multicellular pedicle and a head with cells that secrete essential oil;
– glands – epidermal outgrowths that have received the most
the highest specialization in the extraction and accumulation of essential oils. They have a different structure and can serve as a systematic feature. For example, in yasnotkovye (labial) 8 excretory cells are arranged in a rosette on a short stalk; in aster (composite) glandular cells have a vertical arrangement – 2 in 4 rows, etc.
Endogenous formations develop in parenchymal tissues and are:
– secretory cells – single (for example, in the air parenchyma of calamus rhizome) or form layers of such cells (for example, in valerian roots);
– receptacles – rounded cavities formed in the mesophyll of the leaf, peel of citrus fruits, in the bark and wood of a number of plants and filled with essential oil;
– tubules and passages – strongly elongated excretory formations found in the fruits of umbellate, bark and wood of a number of plants.
Essential oils accumulate in plants in all possible quantities: from hundredths and thousandths of a percent (for example, in violet flowers – 0.004%) to 20% or more (for example, in flower buds of carnations – up to 23%).
Essential oils are obtained: 1) by steam distillation; 2) extraction with some extractants; 3) enfleurage; 4) mechanically.
Steam distillation is the most common method. It is carried out in installations consisting of a double-jacketed still (in which steam circulates to prevent the still from cooling), a condenser and a receiver. Steam is fed into the cube loaded with raw materials from below through a perforated coil, entraining the essential oil. A mixture of cooled vapors of water and essential oil enters the receiver, where the mixture separates and excess water is removed through a tube at the bottom of the receiver (if oil is lighter than water) or through a drain tube at the top (if oil is heavier than water).
The extraction of essential oils from raw materials is carried out with volatile organic solvents in Soxhlet-type apparatuses or in column apparatuses. Subsequently, the raw material is lifted by the screw from the bottom up, and the extractant enters towards it. After distillation of the solvent, the residue is either pure essential oil or its mixture with other extracted substances (resins, waxes, etc.); in the latter case, additional cleaning is required.
Enfleurage is based on the fact that essential oil from raw materials (mainly from flowers) is absorbed by sorbents (solid fats, activated carbon, etc.) in special frame installations.
The mechanical method is used to extract essential oils from citrus fruits by pressing or scraping.
Although essential oils are very common in the plant world, their role for the plant organism and the reasons for their formation have not yet been reliably established. It was assumed that essential oils serve to protect plants from diseases and pests, to attract the smell of insects, which contributes to the pollination of flowers, to protect plants from excessive heating during the day and hypothermia at night, etc. Currently, most scientists believe that essential oils (or rather, their components) are actively involved in the metabolic processes of plant organisms.
Essential oils find a wide and varied application for medicinal, cosmetic, food (spices) and other chains.
Essential oils are classified according to the substances that make up their bulk, or substances that determine their medicinal and industrial value. There are the following groups (and subgroups) of components of essential oils:
Monoterpenes (terpenes), including:
1. Acyclic terpenes.
2. Monocyclic terpenes.
3. Bicyclic terpenes.
Sesquiterpenes, including:
1. Acyclic sesquiterpenes.
2. Cyclic sesquiterpenes.
Aromatic and phenolic compounds.
Sulfur and nitrogen-containing compounds.
The listed compounds, especially terpenoids, in essential oils can occur in the form of numerous oxygen derivatives: alcohols, aldehydes, ketones, phenols, acids, esters, lactones, oxides, quinones. The number of terpenoids also increases due to the tendency of many of these compounds to various forms of isomerism (optical, geometric, etc.).