Thymus Zygis

''Thymus zygis'' is a type of flowering plant in the family Lamiaceae native to the Iberian Peninsula and northern Morocco.

Description

Its leaves are thin and about 8 mm in length. It has white flowers. Sandy and loamy soils are ideal for this species and it is tolerant of nutrient poor soil. It can tolerate acidic to alkaline soil conditions.

Distribution

It is very common in the southern half of Spain, Portugal and in Morocco.

Biology

It is diploid but the chromosome number has been found to vary among the species. The size of the chromosomes are typically between 1-2 μm.

''Thymus zygis'' is a gynodioecious species. As a result, there is a wide range of female frequency (17 – 87%) and a female frequency mean of 51%.

This species is able hybridize with other species of the genus ''Thymus'' when there is overlapping flowering periods.

Subspecies

''T. zygis'' ssp. ''gracilis''

This subspecies is diploid with a chromosome number of 28 (2n = 28).

This subspecies has a greater distribution than the other two subspecies. It has a more erect growth habit than subspecies ''sylvestris''.

''T. zygis'' ssp. ''sylvestris''

This subspecies is diploid with a chromosome number of 56 or 58 (2n = 56, 58).

This subspecies does not grow near the coast. It is found in cold and wet environments which differs from the other two species. It has a denser indumentum when compared with the subspecies ''zygis.''

''T. zygis'' ssp. ''zygis''

This subspecies is diploid with a chromosome number of 28 (2n = 28).

Food

''Thymus zygis'' is used as a food source. It is used as a dried and fresh herb collected from the wild in Spain and Portugal. It is also a popular herb to cultivate and hybridize with other ''Thymus'' species due to its diverse aromatics. However, ''Thymus vulgaris'' is more commonly used as herb than this species.

Essential oils

''Thymus zygis'' is mostly used for the production of essential oils and is the main species used for thyme oil. Due to the high abundance of this species in the Iberian Peninsula, Spain is the dominant country producing essential oil from this species. There are three major regions in Spain that produce thyme oil: Almería, Murcia, and Albacete. In 1989, the production of ''Thymus zygis'' essential oil was 25 tons. From 1990 to 1998, there was between 35 and 45 tons of essential oil produced annually. There is a growing demand for essential oils so it is likely that the production is greater nowadays. Harvesting the plant during its flowering stage yields the highest amount of essential oil and the lowest yield of essential oil was during its dormancy period. The compound composition varies at different stages of the vegetative cycle. The essential oils of this species are store in the glandular peltate trichome. The main compounds of interest in essential oils are thymol, carvacrol, linalool, and ''p''-cymene. The concentration of each compound may be different depending on what plant the essential oil is harvested from. This difference is due to the variety of chemotypes existing for this species. There are multiple chemotypes for each of the subspecies.

Subspecies ''gracilis'' has two major chemotypes: thymol chemotype (maximum 68.1% )and linalool chemotype (maximum 82.3%). The essential oils produced from each respective chemotype are effective ''in vitro'' against some gram-negative and gram-positive strains. Depending on the concentration the essential oils can be bacteriostatic or bactericidal. The findings from this study suggest that the essential oils can be used as natural preservatives to prevent bacterial growth and increase shelf life of certain food items.

Subspecies ''sylvestris'' has four major chemotypes: linalool chemotype (maximum 30.0%), carvacrol chemotype (maximum 25.0%), thymol chemotype (maximum 23.8%), and geranyl acetate/geraniol chemotype (maximum 20.8% and 19.8% respectively). The thymol chemotype is one of the most common chemotypes in Spain. All essential oils derived from each chemotype were shown to be effective against dermatophyte fungal strains with the carvacrol chemotype being the most effective ''in vitro''. Additionally, there was not any cytotoxic effects shown on eukaryotic mammalian cells at concentrations that are effective against dermatophyte strains.

There are a variety of uses for thyme oil. It can be found in the production of perfumes and cosmetics, flavoring of chocolates, toothpaste, mouthwash, and cough medicine.

Polyphenols

''Thymus zygis'' contains flavonoids which is a group within polyphenols. Flavonoids have many functions in plants and in thyme studies have shown that they possess antioxidant properties which helps protect against free radicals.

Polyphenols found in the species and subspecies:

''Thymus zygis''

* Apigenin
* Cirsimaritin
* Luteolin
* 6-OH-Luteolin
* Xanthomicrol
* Vicenin-2

''Thymus zygis'' ssp. ''sylvestris''

* Cirsilineol
* 8-OMe-Cirsilineol
* Cirsimaritin
* 5-Desmethylnobiletin
* 5-Desmethylsinensetin
* Sideritoflavone
* Thymonin
* Thymusin
* Xanthomicrol

''Thymus zygis'' ssp. ''zygis''

* Cirsilineol
* 8-OMe-Cirsilineol
* Cirsimaritin
* 5-Desmethylnobiletin
* 5-Desmethylsinensetin
* Sideritoflavone
* Thymonin
* Thymusin
* Xanthomicrol

Common names

Some English common names are Spanish thyme and white thyme. Since it is endemic to the Iberian Peninsula it has many common names that are not of English origin. Below is a list of non-English common names.

References

{{Taxonbar, from=Q851544

zygis