臨床および実験薬理学ジャーナル

概要

Phytochemical Constituents, Safety and Efficacy Study of Thymus schimperi and Thymus serrulatus

Abera T, Debebe E, Ashebir R, Abebe A, Basha H, Kasahun T and Sisay B

Background: The genus Thymus is one of the most taxonomically complex genera in the Lamiaceae family and it includes 250- 350 taxa (species and varieties). T. serrulatus Hochst. ex Benth and T. schimperi Ronniger are the two species of thymus which are endemic to Ethiopia; locally known as Tosign. According to WHO 2018 report, NCDs (non-communicable disease) are estimated to account for 39% of all deaths in Ethiopia and Infectious diseases also represent a continuous and increasing threat to human health in developing countries like Ethiopia. In Ethiopia, 80% of the population use plant remedies or medicinal plants over centuries.

Objective: The present study aimed to review Phytochemical-constituents, Safety and Efficacy Study of Thymus schimperi and Thymus Serrulatus.

Method: A web-based literature search was done by using scientific databases including Pub Med, Science Direct, Google Scholar and Scopus. Searching was made using key words: Thymus, Thymus schimperi, Thymus Serrulatus, phytochemistry, pharmacology, ethnomedicine, efficacy and safety.

Results: T. serrulatus grows in Tigray, Gondar, Bale, in the highlands of Semien Shoa and Wollo whereas T. schimperi is widely distributed in Oromia, Amhara and Southern Nations Nationalities & Peoples Regions. T. serrulatus and T. schimperi belong to the chemotypes Carvacrol-Thymol. Carvacrol (63%), thymol (36%-38%), Thymol (49%) are the major constituent of the essential oil of T. schimperi collected from Bale, T. schimperi from Gonder, Shewa & Wello, T. serrulatus from the Tigray region respectively. Treatment of mice with 2000 mg/kg dose of the essential oil of T. schimperi caused 50% mortality indicating that it’s the LD50 is about 2000 mg/kg. However, n-butanol fraction of the aqueous and crude methanol leaf extract T. serrulatus with the oral limit dose of 5,000 mg/kg showed no sign of overt behavioral changes and toxicity where the LD50 were above 10,000 mg/kg. n-butanol fraction and the crude aqueous extract of T. serrulatus has exhibited an increase in urine volume with the highest urine output at the highest dose (1,000 mg/kg) and an appreciable diuretic activity of 94% and 92% respectively.

Conclusion and Recommendation: The essential oil of T. schimperi did not cause a rise in serum enzyme level and major organ damage (kidney and liver), but the dose range of 2000 mg/kg causes 50% mortality. The n-butanol fraction of crude aqueous leaf extract of T. serrulatus showed an increase in urine volume with the highest urine output at the highest dose (1,000 mg/kg) and appreciable diuretic activity (94%). Additional chemical isolation, development of dosage form, clinical trial and toxicological study is recommended.