Journal of Medicinal Plants Biotechnology

Abstract The genus Thymus is one of the plants with a Mediterranean distribution. This plant has about 350 species and in Iran there are 14 species of aromatic and perennial plants that grow in mountainous areas and have an important impact on treatment, health and various industries due to having more than 20 types of major known chemical compounds. The percentage of thyme essential oil varies between 0.8 and 1.4 and most of its components include phenolic compounds, monoterpenes and sesquiterpenes. Thymol is the main component of phenolic compounds in the thyme plant. Thyme leaves are used in food products and the plant's essential oils is used in various beverages and pharmaceutical, health and cosmetic industries. Thyme oil has properties such as antispasmodic, carminative, antifungal, antibacterial, disinfectant, anthelmintic, antirheumatic, expectorant, antioxidant, natural food preservative and delaying the aging of mammals. Thyme essential oil is one of the ten famous essential oils that has a special place in global trade. This study provides a general overview of scientific research and findings, especially the species and morphological and phytochemical diversity of the Thyme genus. So far, much research has been conducted on this genus, but due to the high diversity of species in this genus, as well as diverse climatic and ecological effects and numerous subspecies, there is no appropriate conclusion in this regard. It is hoped that by summarizing the findings of the researchers, a new horizon can be opened in the study of endemic species of Iran and high-yielding varieties worldwide.

Abstract Saffron (Crocus sativus L.) is one of the oldest medicinal and spice plants in the world. Several factors affect the growth and production of saffron including: age and the number of corms per surface area, soil texture, the time of plant culture, time and kind of irrigation, mineral nutrition and ecological factors. It seems that the quantity and quality of saffron products are greatly different at different plant ages. The plant or field age has important effect on growth indices of saffron and its secondary metabolites. In order to investigate the effects of plant age on secondary metabolites and some physiological factors of saffron, a research project was conducted in a completely randomized design with three replications at the research field of medicinal plants of the University of Zanjan. Three saffron farms with different biological ages of one, two and five years old were selected as experimental treatments, and then three plots were randomly selected from each farm and the desired traits were measured. Results showed that, increasing of the age of saffron plants in this experiment increased fresh weight of plant and dry weight of stigma. 5-yraes old plants showed the highest amounts of these traits. Whereas, the contents of soluble proteins and sugars and photosynthetic pigments were higher at first year and decreased by increasing of plant age. Number of secondary metabolites decreased when the age of plants increased as in one–year old saffron plants 26 metabolites and in 5-year old plants only 15 metabolites were detected. Loliolid (18%) and thymol (17%) in 1-year old plants and thymol (19%) and camphor (14%) in 5-year old plants showed the highest level among all detected secondary compounds. Generally according to these results, plant age has an important effect on the number and kinds of secondary metabolites in saffron which should be considered at the time of saffron harvesting.   

Abstract

Abstract Bacterial resistance is one of the problems in the world of medicine today. Many efforts are underway to find alternative methods, one of which is to use the capacity of native plants of each region. The chamber was powdered as a homogeneous mixture and its essential oil was extracted by water distillation. Then, the components of the essential oil were identified and the amount of the components was identified using a gas chromatography device connected to a mass spectrometer. GC-Mass analysis showed that the most important effective compounds with antimicrobial activity of this plant were 2- boronanone (12.36%), camphor (6.87%), 3-carn (5.35%). The range of growth inhibition zone varied from 9 to 40 mm. Essential oil with growth inhibition zone of 40 mm had the greatest effect against Staphylococcus aureus even in comparison with clindamycin, although essential oils had no effect on Pseudomonas aeruginosa and could not inhibit its growth. In general, essential oils had a better effect on gram-positive bacteria than gram-negative bacteria.