Effect of Ecological Factors on Plant Properties of Thymus daenensis Celak in Different Regions in Southwest and Central Iran

Thymus daenensis Celak. (Lamiaceae) is an aromatic medicinal plant endemic to Iran, intensively utilized because of its wide ranging medicinal and culinary properties. The aerial parts of wild populations of T. daenensis were collected from different populations in Isfahan and Chaharmahal and Bakhtiari provinces, Southwest and Central Iran. The thymol and carvacrol amounts ranged between 13.89 to 35.89 mg g-1 and 6.88 to 23.54 mg g-1 respectively, for populations collected from various elevations. Also, our investigation showed that plant height and date of flowering between populations of T. daenensis had significant difference. The cluster analysis showed that the amount of thymol and carvacrol, and plant height of T. daenensis could be grouped into two distinctive clusters. The results indicate that the amount of thymol and carvacrol of T. daenensis are strongly affected by environmental conditions. Since secondary metabolites are the product of a predominantly biological process further studies are needed to evaluate if the reported characteristics of each population are maintained at the level of individual plants and along the breeding and selection program when grown under different soil and climatic conditions

Effect of Harvest Time on Yield and Quality of Thymus vulgaris L. Essential Oil in Isfahan Province, Iran

Thyme (Thymus vulgaris L.) is a perennial sub shrub belonging to family Lamiaceae. Thyme essential oils have been used for many thousands of years, especially in food preservation, pharmaceuticals, alternative medicine and natural therapies. In order to determine the effect of harvest time on quality and quantity of essential oil in thyme, this experiment was done in a randomized complete block design with three replications at research station of Islamic Azad University, Khorasgan (Isfahan) during 2010-2011. Plants were harvested in five stages: before blooming, beginning of blooming, 50% blooming, full blooming and fruit set. The essential oils obtained from the phenological stages of thyme were analyzed by using GC/MS. The results obtained in our study showed that the phenological stages had very significant effects (P < 0.01) on essential oil yield and percentage as well as thymol percentage and yield. The highest essential oil content of thyme (2.42%) was extracted at the beginning of blooming stage. Analysis and identification of components showed that thymol is the main compound in all samples. The highest thymol content of thyme (74.8%) was extracted at the full blooming stage. According to the results of this research, harvesting the thyme at 50% blooming stage have maximum essential oil quality and quantity in Isfahan province

Effect of Harvest Time on Yield and Quality of Thymus vulgaris L. Essential Oil in Isfahan Province, Iran

Thyme (Thymus vulgaris L.) is a perennial sub shrub belonging to family Lamiaceae. Thyme essential oils have been used for many thousands of years, especially in food preservation, pharmaceuticals, alternative medicine and natural therapies. In order to determine the effect of harvest time on quality and quantity of essential oil in thyme, this experiment was done in a randomized complete block design with three replications at research station of Islamic Azad University, Khorasgan (Isfahan) during 2010-2011. Plants were harvested in five stages: before blooming, beginning of blooming, 50% blooming, full blooming and fruit set. The essential oils obtained from the phenological stages of thyme were analyzed by using GC/MS. The results obtained in our study showed that the phenological stages had very significant effects (P < 0.01) on essential oil yield and percentage as well as thymol percentage and yield. The highest essential oil content of thyme (2.42%) was extracted at the beginning of blooming stage. Analysis and identification of components showed that thymol is the main compound in all samples. The highest thymol content of thyme (74.8%) was extracted at the full blooming stage. According to the results of this research, harvesting the thyme at 50% blooming stage have maximum essential oil quality and quantity in Isfahan province

Diversity in chemical composition and yield of essential oil from two Mentha species

The genus Mentha, which belongs to the mint family (Lamiaceae). Essential oil yield and chemical components of two Mentha species including Mentha longifolia (L.) Huds. and (Mentha spicata L.) collected from three ecotypes in Iran were investigated. The essential oils of samples were obtained by hydro-distillation, and analyzed using gas chromatography-mass spectrometry (GC-MS). A significant difference (p < 0.05) in oil yields was obtained from the aerial parts of two Mentha species. The essential oil yields were obtained from the aerial of M. longifolia, 0.62, 0.85 and 1.24 ml / 100 g dry matter identified in Ardestan, Saman and Kuhrang province, respectively and the aerial of M. spicata, 0.49, 1.02 and 1.54 ml / 100 g dry matter identified in Ardestan, Saman and Kuhrang province, respectively. Results indicated significant differences (p < 0.01) among the aerial for the main constituents in the essential oil from two Mentha species. The major constituents of the essential oil from the aerial of M. longifolia collected from Ardestan province were pulegone (31.21%), 1,8-cineole (23.01%), sabinene (6.76%), the aerial of M. longifolia collected from Saman province were pulegone (31.06%), 1,8-cineole (24.34%), sabinene (7.45%) and the aerial of M. longifolia collected from Kuhrang province were pulegone (36.42%) and 1,8-cineole (29.49%). The major constituents of the essential oil from the aerial of M. spicata collected from Ardestan province were 1,8-cineole (35.28%), carvone (30.71%), the aerial of M. spicata collected from Saman province were carvone (35.37%), 1,8-cineole (24.35%), pulegone (18.67%) and the aerial of M. spicata collected from Kuhrang province were carvone (41.51%), 1,8-cineole (25.95%). Generally, a comparison of our results with the previous reports suggests differences in the essential oil compositions and oil yield of the plant material could be attributed to genetic diversity in two Menthe species

Potential antidiabetic phytochemicals in plant roots : a review of in vivo studies

Background: Medicinal plants are used to treat various disorders, including diabetes, globally in a range of formulations. While attention has mainly been on the aerial plant parts, there are only a few review studies to date that are focused on the natural constituents present in the plant roots with health benefits. Thus, the present study was performed to review in vivo studies investigating the antidiabetic potential of the natural compounds in plant roots. Methods: We sorted relevant data in 2001–2019 from scientific databases and search engines, including Web of Knowledge, PubMed, ScienceDirect, Medline, Reaxys, and Google Scholar. The class of phytochemicals, plant families, major compounds, active constituents, effective dosages, type of extracts, time of experiments, and type of diabetic induction were described. Results: In our literature review, we found 104 plants with determined antidiabetic activity in their root extracts. The biosynthesis pathways and mechanism of actions of the most frequent class of compounds were also proposed. The results of this review indicated that flavonoids, phenolic compounds, alkaloids, and phytosteroids are the most abundant natural compounds in plant roots with antidiabetic activity. Phytochemicals in plant roots possess different mechanisms of action to control diabetes, including inhibition of α-amylase and α-glucosidase enzymes, oxidative stress reduction, secretion of insulin, improvement of diabetic retinopathy/nephropathy, slow the starch digestion, and contribution against hyperglycemia. Conclusion: This review concludes that plant roots are a promising source of bioactive compounds which can be explored to develop against diabetes and diabetes-related complications. Graphical abstract: [Figure not available: see fulltext.

Determination of the best indirect selection criteria in Iranian durum wheat (Triticum aestivum L.) genotypes under irrigated and drought stress conditions

In order to evaluate and classify morphological and morpho-physiological traits of durum wheat genotypes in drought and irrigated conditions 200 durum wheat genotypes were sown in modify augmented design with four replications during 2013- 2014 farming season. Two replications were considered as drought condition and two as irrigated. Factor analysis based on principal component analysis method and varimax rotation indicated that four important factors accounted for about 87 and 92 percent of the total variation among traits in drought and irrigated conditions, respectively. In drought stress condition, the first factor assigned 37 percent of total variation between traits and was significantly related with spike yield and it’s components. Therefore, this factor was regarded as spike seed yield factor. Other factors in drought stress condition accounted for 22, 16 and 12 percent of variation between traits and were entitled as plant seed yield, spike density and assimilate transmission factors, respectively. In irrigated condition, the first factor assigned 36 percent of total variation between traits and was significantly related with traits plant and spike seed yield, plant and spike harvest index, No. seed/spike and plant height. This factor was regarded as plant seed yield factor. Other factors in irrigated condition accounted for 24, 18 and 14 percent of variation between traits and were entitled as production, assimilate transmission and spike density factors, respectively. Overall, results revealed effect of different environments on extracted factors, percent of variation accounted for by factors and traits related with each factor