Thyme (Thymus) - quite numerous and polymorphic genus, about which taxonomists do not cease to argue. In the literature of different countries, there is a mention of thyme, but it is often impossible to understand what kind of species it is talking about.
In modern pharmacy of the Russian Federation, the herb has medicinal value creeping thyme (Thymus serpyllum L. s.l.) (Herba Serpylli) and related species - thyme marshall (Thymus marschallianus Willd.), As well as cultivated in the south of Russia thyme common (Thymus vulgaris L.). In Europe, common thyme is used, but, besides it, many more species and hybrids are used in aromatherapy and in the kitchen..
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All representatives of the genus are among the valuable essential oil plants that are widely used in the food and canning industry, and some even in perfumery. In addition, thyme is promising for use in landscaping, as ornamental and phytoncidal plants. Therefore, of course, the question arises as to whom and how can be used. Although it should immediately be noted that many species are southerners, and they will not want to grow in the middle lane. But first things first.
All representatives of the genus are undersized, creeping, occasionally erect, aromatic shrubs and semi-shrubs originating from the Mediterranean of Western Asia.
All species of the thyme genus contain various biologically active compounds: tannins and bitter substances, flavonoids, essential oil, organic acids (derivatives of caffeic acid, primarily rosemary), triterpenes (oleic and ursolic acids), mineral salts, gums, resins, saponins, glycosides, etc. However, given the wide variety of species and their polymorphism, the composition of medicinal raw materials varies greatly. The composition of the essential oil of the most interesting for medicine thyme contains from 40 to 80 substances, among which thymol (up to 65%), carvacrol (up to 45%), n-cymene, a-terpinolene, borneol, etc. fluctuates in the range of 0.1-7.0%.
The first systematic information about the genus Thymus can be found in the works of the outstanding Swedish taxonomist Karl Linnaeus (1738; 1748; 1753; 1767). In Hortus Cliffortianus (1737) he describes six species, of which two do not belong to the genus Thymus, and are representatives of the genus Satureja and Acinos... Of the kind Thymus they were described: Th. erectus (now - Th. vulgaris); Th. repens (Thymbra capitata); Th. mastichina... In a later work, Hortus Upsaliensis (1748), he only mentions Th. vulgaris and Th. mastichina.
And over the period after K. Linnaeus, a huge variety of species, subspecies, varieties and forms have been described.
Each author singled out species in accordance with his understanding and, as a result, in the genus Thymus more than 800 systematic combinations were registered (Index Kewensis, 19th century). When there were already a lot of taxa, this led to confusion and the question arose about revising the genus and developing a unified convenient classification. As a result, the famous English botanist and specialist in the family Labiatae George Bentham (1800-1884) divided the genus Thymus into three sections according to the type of structure of the teeth of the calyx, the size and shape of the bracts: Mastichina, Pseudothymbra and Serpyllum... Representatives of the first two sections are well distinguished and distributed exclusively within the Mediterranean region (Spain, Algeria, Morocco), the third section is polymorphic and has a significant distribution area in the European part, in fact, it is precisely its representatives that are found in the Russian flora.
And at present, the volume of the genus is ambiguously assessed by domestic and foreign taxonomists.
Genus Thymus has distribution exclusively in the countries of the Old World, in the temperate zone of Europe, Asia and northern Africa, without covering the tropical, desert and arctic regions of this vast territory. However, the primary center of origin of the genus and the starting point for further migration is the Ancient Mediterranean, namely, the western part of the Mediterranean region, where their greatest species diversity is observed.
In the process of adaptation to new habitats within the genus, and even in individual species, microevolutionary processes took place.New species, subspecies, chemo- and ecotypes arose. Summarizing modern research on the chemical composition of labiate essential oils, thyme can be divided into two large groups. The first group includes those species in the composition of the essential oil of which aromatic alcohols (thymol, carvacrol) and their biosynthetic precursors (g-terpinene, r-cymene) play a dominant role. But the funny thing is that this division does not always coincide with the division into species. Within the same species, plants of different subspecies smell completely differently.
Of our thyme, thymol aroma is characterized by t. hill (Th. collinus), T. Dagestan (Th. daghestanicus), t. Fedchenko (Th. fedtschenko), t. Kochi (Th. kotschyanus), T. Krylova (Th. krylovii), T. Marshall (Th. marschallianus Willd), T. pale (Th. pallidus), T. rare-flowered (Th. rariflorus), T. Transcaucasian (Th. transcaucasicus) and of course, T. creeping (Th. serpyllum).
Marshall thyme (Thymus marschallianus Willd.) Is an East European-West Siberian species. It mainly covers the European part of Russia, Western Siberia, the Republic of Kazakhstan, the Caucasus. It is confined to steppe and meadow-steppe communities on well-developed soils, from the lower to the middle belt of mountains.
Of the European species, they differ in high thymol thyme common (Thymus vulgaris) and some other types.
Thyme white (Thymus zygis L.) grows mainly in Spain, and its essential oil is also produced there. Mainly use 2 subspecies Thymus zygis L. var. gracilis Bois ... and Thymus zygis L. var. floribundus Bois. The oil content reaches 1%, and the content of phenols (primarily thymol) is 50-60%. Naturally, the oil has a strong antimicrobial effect and is used in medicine and aromatherapy, mainly for the preparation of ointments and sometimes as a culinary additive to meat and sauces. And the herb is used for colds. The main supplier of this type of thyme oil is Spain and Morocco, where it has been produced since the French rule.
Other subspecies differ greatly in their main component. So Thymus zygis L. var. capitatus W.K. has a very low content of phenols (2%), 12-35% 1,8-cineole and 3% citrals, which give the oil a lemon flavor. Thymus zygis L. var. loscossi W.K. has the smell of marjoram and laurel. These subspecies are sometimes used in local cooking to flavor olive oil.
In Spain, to obtain a special mixture of essential oils, they also use Thymus hiemalis lange and Thymus hirtus Willd... A blend of these lemon-scented oils is often sold as Spanish verbena oil.
Thyme (Thymus hiemalis Lange), another name is lemon thyme or Spanish verbena. The oil has a lemon scent and is indeed similar to verbena oil (Lippia citriodora (Lam.) Knuth.), Its main components are citral (up to 34%) and limonene (up to 50%).
Thyme (Thymus hirtus Willd.) Grows wild in Spain (province of Granada). An essential oil is obtained from it, which smells like an essential oil obtained from Thymus hiemalis. Contains limonene (25%), linalool (28%), fenchon (30%), citral (up to 12%).
Linaool thymes include Early flowering thyme, or early (Th. praecox), Th. eriphorus, Th. tosevii, Th. leptophyllus.
Thyme capitate (Thymus capitatus (L.) Hoffmanns. et Link., Coridothymus capitatus Rchb.), Another name is Spanish oregano. A wild herb popular in the Middle East as a food flavoring. The essential oil is obtained by steam distillation of fresh leaves. The highest quality ("red") oil comes from Spain. An oil of this color with a yield of 0.87% is obtained by steam distillation of the whole plant. After repeated vacuum distillation, a yellowish so-called "white oil" can be obtained. Its main component is carvocrol (60-75%), and the thymol content does not exceed 5%.
"Spanish marjoram" (Thymus mastichina L.) - wild (or forest) thyme of Spanish origin, which has the commercial name "Spanish marjoram" is used to obtain essential oil. From a flowering plant by steam distillation with a yield of 0.12%, a slightly yellow essential oil with a camphor smell is obtained. Manufacturer - Spain. The oil is exported mainly to the USA. The composition of Spanish marjoram essential oil is subject to fluctuations. This is especially true for the content of linalool, which can fluctuate within 4-60% with a corresponding change in the content of 1,8-cineole.
Portugal also offers essential oil under the same name, but some batches of it are very different in their chemical composition from the Spanish, since it is not cineole that predominates in the oil, but linalool (more than 70%).
Borneol is one of the dominant components in Th. satureioides (26%), Th. quinquecostatus (31%), Th. carnosus (51%). A significant portion of the essential oil Th. cilicicus and Th. revolutus represents a-terpineol (33 and 30%, respectively).
Camphor thyme (Thymus camphoratus) contains up to 90% 1,8-cineole and has a strong camphor odor. Along with another species similar in composition (Thymus cephalotus L.) essential oil is used as an additive in various sauces and for flavoring soups.
In general, as already mentioned, thyme is the record holder for polymorphism, including chemical one. Therefore, representatives of the same species can smell differently, including lemon. Therefore, we often find such a name as lemon thyme or lemon thyme. But only the lemon-smelling form of creeping thyme or common thyme can be mentioned so. Both are of this variety .. In the scientific literature, lemon-scented thyme is stated as: Thymus comptus, T. jankae, Th. serpillum var citriodorum, Th. lanuginosum var citriodora... However, recently, a natural hybrid has also been indicated as an independent species Th. pulegioides x Th. vulgariscommon in southern France. it lemon-scented thyme(Thymus x citriodorus), well known for variegated and yellow-leaved varieties.
