Applications of Essential Oils and Plant Extracts in Different Industries.

Essential oils (EOs) and plant extracts are sources of beneficial chemical compounds that have potential applications in medicine, food, cosmetics, and the agriculture industry. Plant medicines were the only option for preventing and treating mankind's diseases for centuries. Therefore, plant products are fundamental sources for producing natural drugs. The extraction of the EOs is the first important step in preparing these compounds. Modern extraction methods are effective in the efficient development of these compounds. Moreover, the compounds extracted from plants have natural antimicrobial activity against many spoilage and disease-causing bacteria. Also, the use of plant compounds in cosmetics and hygiene products, in addition to their high marketability, has been helpful for many beauty problems. On the other hand, the agricultural industry has recently shifted more from conventional production systems to authenticated organic production systems, as consumers prefer products without any pesticide and herbicide residues, and certified organic products command higher prices. EOs and plant extracts can be utilized as ingredients in plant antipathogens, biopesticides, and bioherbicides for the agricultural sector. Considering the need and the importance of using EOs and plant extracts in pharmaceutical and other industries, this review paper outlines the different aspects of the applications of these compounds in various sectors.

Differential effects of biogenic and chemically synthesized silver-nanoparticles application on physiological traits, antioxidative status and californidine content in California poppy (Eschscholzia californica Cham).

Silver nanoparticles (AgNPs) of both biologically and chemically origins trigger various physiological and metabolic processes through interaction with plant cells, exerting positive, negative and inconsequential effects. However, their impacts on plant systems must be critically investigated to guarantee their safe application in food chain. In this study, the effects of chemically synthesized (synthetic) AgNPs (sAgNPs) and biologically synthesized (biogenic) AgNPs (bAgNPs) on physiological and biochemical features of Eschscholzia californica Cham were evaluated at different concentrations (0, 10, 25, 50 and 100 mg L-1). Plants exposed to bAgNPs (at 10 and 25 mg L-1) and sAgNPs (at 10 mg L-1) displayed relatively uniform deposition of AgNPs on leaf surface, however, the higher concentration (100 mg L-1) was accompanied by aggregation of AgNPs, resulting in anatomical and physiological disorders. Foliar application of both AgNPs at lower concentrations resulted in significant (P < 0.01) improve in the content of photosynthetic pigments (chlorophylls a, b, a+b, and carotenoids) and total phenolics over the control in a dose-related manner. Leaf relative water content decreased steadily with increasing both sAgNPs and bAgNPs concentrations-with sAgNPs being more inhibitive. Both types of AgNPs at 100 mg L-1 significantly (P < 0.05) increased electrolyte leakage index, level of lipid peroxidation product (malondialdehyde), and leaf soluble sugar content when compared to controls. No significant difference was found on cell membrane stability index among the plants exposed to bAgNPs and sAgNPs at the lowest concentration over the control. Californidine content was significantly (P < 0.01, by 45.1%) increased upon all the bAgNPs treatments (with a peak at 25 mg L-1) relative to control. The obtained extracts from plants treated with bAgNPs at lower concentrations revealed a significant induction of antioxidant capacity (based on DPPH˙ free radical scavenging and ferrous ions-chelating activities) with lower IC50 values compared to the other treatments. Conclusively, bAgNPs at lower concentrations are potent elicitors of pharmaceutically active compounds biosynthesis, which enhance physiological efficiency of E. californica, but at higher concentrations bAgNPs are equally toxic as sAgNPs.

Metabolomics Approaches for Analyzing Effects of Geographic and Environmental Factors on the Variation of Root Essential Oils of Ferula assa-foetida L.

Environmental factors shape the production and accumulation processes of plant secondary metabolites in medical and aromatic plants and thus their pharmacological and biological activity. Using an environmental metabolomics approach, we determined chemotypes and specific compounds on the basis of essential oils (EOs) from roots of 10 Iranian Ferula assa-foetida L. populations and related them to geographical, climate, and edaphic data. GC-MS revealed three distinct chemotypes characterized by (I) monoterpenes and Z-1-propenyl sec-butyl disulfide; (II) eudesmane sesquiterpenoids and α-agarofuran; and (III) Z- and E-1-propenyl sec-butyl disulfide. NIRS measurements indicated a similar but less distinct pattern. Structural equation models showed that EO constituents and content were directly influenced by edaphic factors (texture, pH, and iron, potassium, and aluminum content) and temperature and predominantly indirectly by latitude, longitude, and altitude. Predicting EO constituents or chemotypes by geographical, climate, and soil factors can be used in F. assa-foetida to select populations with specific EO characteristics.

Variation of Secondary Metabolite Profile of Zataria multiflora Boiss. Populations Linked to Geographic, Climatic, and Edaphic Factors.

Geographic location and connected environmental and edaphic factors like temperature, rainfall, soil type, and composition influence the presence and the total content of specific plant compounds as well as the presence of a certain chemotype. This study evaluated whether geographic, edaphic, and climatic information can be utilized to predict the presence of specific compounds from medicinal or aromatic plants. Furthermore, we tested rapid analytical methods based on near infrared spectroscopy (NIR) coupled with gas chromatography/flame ionization (GC/FID) and gas chromatography/mass spectrometry (GC/MS) analytical methods for characterization and classification metabolite profiling of Zataria multiflora Boiss. populations. Z. multiflora is an aromatic, perennial plant with interesting pharmacological and biological properties. It is widely dispersed in Iran as well as in Pakistan and Afghanistan. Here, we studied the effect of environmental factors on essential oil (EO) content and the composition and distribution of chemotypes. Our results indicate that this species grows predominantly in areas rich in calcium, iron, potassium, and aluminum, with mean rainfall of 40.46 to 302.72 mm·year-1 and mean annual temperature of 14.90°C to 28.80°C. EO content ranged from 2.75% to 5.89%. Carvacrol (10.56-73.31%), thymol (3.51-48.12%), linalool (0.90-55.38%), and p-cymene (1.66-13.96%) were the major constituents, which classified 14 populations into three chemotypes. Corresponding to the phytochemical cluster analysis, the hierarchical cluster analysis (HCA) based on NIR data also recognized the carvacrol, thymol, and linalool chemotypes. Hence, NIR has the potential to be applied as a useful tool to determine rapidly the chemotypes of Z. multiflora and similar herbs. EO and EO constituent content correlated with different geographic location, climate, and edaphic factors. The structural equation models (SEMs) approach revealed direct effects of soil factors (texture, phosphor, pH) and mostly indirect effects of latitude and altitude directly affecting, e.g., soil factors. Our approach of identifying environmental predictors for EO content, chemotype or presence of high amounts of specific compounds can help to select regions for sampling plant material with the desired chemical profile for direct use or for breeding.

Deciphering morpho-physiological and phytochemical attributes of Tanacetum parthenium L. plants exposed to C60 fullerene and salicylic acid.

This study was aimed to evaluate the effects of C60 fullerene concentrations (0, 125, 250, 500 and 1000 mg/L) and salicylic acid (0 and 0.2 mM) on growth and phytochemical accumulation of two feverfew genotypes (Pharmasaat and Jelitto) in a factorial experiment based on completely randomized design with three replications. According to the ANOVA, triple interaction of treatments were significant on morphological and phytochmical traits, however, the main effect of treatments only affected physiological attributes. Application of salicylic acid differentially influenced the effects of various concentrations of C60 fullerene on growth traits of both genotypes. In Pharmasaat, foliar application of salicylic acid increased growth traits of plants exposed to C60 fullerene at all concentrations, however, it improved the growth of Jelitto at higher levels of fullerene. The maximum increase of flower + leaf dry weight was recorded at 1000 mg/L C60 fullerene in combination with salicylic acid compared to control for Jelitto. In Pharmasaat, the parthenolide content significantly increased following increase of C60 fullerene up to 250 mg/L with salicylic acid, but a rapid decrease followed at 500-1000 mg/L. SEM images showed a wider deposition (many spheres with different sizes) of C60 fullerene on leaf tissue of Pharmasaat exposed to high concentration, involving changes in trichome density and tissue rupture. The essential oil content was not significantly increased upon experimental treatments compared to control. Based on hierarchical cluster analysis, C60 fullerene and salicylic acid treatments caused to a co-induction of ion leakage, chlorophyll a, essential oil and parthenoloide in Pharmasaat.

Salicylic Acid and Melatonin Alleviate the Effects of Heat Stress on Essential Oil Composition and Antioxidant Enzyme Activity in Mentha × piperita and Mentha arvensis L.

The aim of this study was to evaluate changes in the chemical profile of essential oils and antioxidant enzymes activity (catalase CAT, superoxide dismutase SOD, Glutathione S-transferases GST, and Peroxidase POX) in Mentha × piperita L. (Mitcham variety) and Mentha arvensis L. (var. piperascens), in response to heat stress. In addition, we used salicylic acid (SA) and melatonin (M), two brassinosteroids that play an important role in regulating physiological processes, to assess their potential to mitigate heat stress. In both species, the heat stress caused a variation in the composition of the essential oils and in the antioxidant enzymatic activity. Furthermore both Salicylic acid (SA) and melatonin (M) alleviated the effect of heat stress.

Micronutrient and heavy metal concentrations in basil plant cultivated on irradiated and non-irradiated sewage sludge- treated soil and evaluation of human health risk.

Gamma irradiation is regarded as a promising alternative method for sewage sludge (SS) treatment. To evaluate the human health risk and effects of gamma irradiated and non-irradiated SS (SSGI and SSNI, respectively) on micronutrient and heavy metal concentrations in basil (Ocimum basilicum L.) as a test plant, a greenhouse experiment based on completely randomized design was conducted with control (without SS and irradiation) and 15, 30 and 60 g kg-1 of SSNI as well as SSGI (irradiated with doses of 5, 10 and 20 kGy) with three replicates. The results indicated that the concentrations of copper, zinc, iron, nickel, lead, and cadmium in SSGI and SSNI treatments were greater than the limits set by FAO/WHO for vegetables or by European Commission for food. The target hazard quotient (THQ) of all metals except lead in the treatments with >15 g kg-1 SSGI or SSNI and the hazard index (HI) in the control treatment were lower than the threshold value of 1, but the HIs in SSNI and SSGI treatments were greater than the threshold value. Nevertheless, no significant differences existed between most THQs and HIs from dietary intake of basil grown in SSGI as compared with SSNI. It was concluded that the basil cultivated under tested levels of SSGI and SSNI is not permissible for human consumption.

Metabolite profiling and molecular responses in a drought-tolerant savory, Satureja rechingeri exposed to water deficit.

This study aimed to determine the response of Satureja rechingeri to water deficit by quantifying the expression of three targeted genes and four traditional reference genes using quantitative real-time PCR analysis (RT-qPCR). Drought stress was imposed by withholding water 4 months after planting. Profiling of volatile and non-volatile compounds using gas chromatography/mass spectrometry (GC/MS) and high-performance thin layer chromatography (HPTLC) showed an increasing-decreasing trend of major phenolic and terpenoid compounds such as rosmarinic and caffeic acids, carvacrole, thymol and p-Cymene. Drought stress also lead to significant increases in oil yield, soluble sugars and proline as well as significant reductions in leaf water potential (LWP), relative water content (RWC), and pigments. Metabolite profiling revealed the strategies savory employed to generate different biochemical phenotypes. RT-qPCR analysis showed that up-regulation of the three genes [1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR), 3-hydroxy-3-methylglutaryl-coenzyme. A reductase (HMGR) and rosmarinic acid synthase: 4-coumaroyl-CoA (RAS)] selected from the phenylpropanoid and terpenoid biosynthesis pathways were markedly enhanced at the transcript levels of the regulatory steps and directly increased the production of secondary metabolites, including phenolic and terpenoid compounds. Actin protein (ACT), elongation factor 1-α (EF1α), glyceraldehyde-3-phosphate dehydrogenase cytosolic (GAPC) and ubiquitin-conjugating enzyme (UBC) were used as traditional reference genes. UBC's suitability as the reference genes were verified in S. rechingeri. The study's results provide the foundation for gene expression analysis of savory and other species of Lamiaceae. Thus, the effective application of drought stress before harvesting can increase the quantity and quality of raw material.

Effect of Heat Stress on Yield, Monoterpene Content and Antibacterial Activity of Essential Oils of Mentha x piperita var. Mitcham and Mentha arvensis var. piperascens.

Heat stress affects the yield of medicinal plants and can reduce biomass and/or metabolite production. In order to evaluate the effect of heat-induced stress on the essential oil production in Mentha x piperita L. var. Mitcham (Mitcham mint) and Mentha arvensis var. piperascens Malinv. ex L. H. Bailey (Japanese mint), we studied the chemical composition of the oils of the two mint species under different heat shock stresses in growth chambers. The antibacterial activity of the essential oils was also evaluated; microscopic observation (fluorescence and electron transmission) was used to assess the effect of the tested samples on bacterial growth. The results obtained shed light on the mint essential oils composition and biological activity in relation to heat stress.

Genetic and Chemical Diversity in Perovskia abrotanoides Kar. (Lamiaceae) Populations Based on ISSRs Markers and Essential Oils Profile.

Genetic and the essential oil composition variability among twelve Perovskia abrotanoides populations (PAbPs) growing wild in Iran were assessed by ISSR markers, GC-FID and GC/MS, respectively. Nine selected ISSR primers produced 119 discernible bands, of them 96 (80.7%) being polymorphic. Genetic similarity values among populations ranged between 0.07 and 0.79 which indicated a high level of genetic variation. Polymorphic information content, resolving power and marker index generated by ISSR primers were, 0.31, 6.14, and 3.32, respectively. UPGMA grouped PAbPs into four main clusters. Altogether, 38 chemical compounds were identified in the oils, and a relatively high variation in their contents was found. Camphor (11.9 - 27.5%), 1,8-cineole (11.3 - 21.3%), α-bisabolol (0.0 - 13.1%), α-pinene (5.9 - 10.8%), and δ-3-carene (0.1 - 10.5%) were the major compounds. Oxygenated monoterpenes (32.1 - 35.8%) and monoterpene hydrocarbons (25.7 - 30.4%) were the main groups of compounds in the oils studied. Cluster analysis and principal-component analysis were used to characterize the samples according to oil components. Four main chemotypes were found to be Chemotype I (camphor/1,8-cineol), Chemotype II (1,8-cineole/camphor), Chemotype III (camphor/1,8-cineol/α-bisabolol), and Chemotype IV (camphor/δ-3-carene/α-bisabolol). The information, provided here on P. abrotanoides populations, will be useful to introduce this plant into agricultural systems.

Mechanisms underlying toxicity and stimulatory role of single-walled carbon nanotubes in Hyoscyamus niger during drought stress simulated by polyethylene glycol.

In this study, seeds of Hyoscyamus niger were exposed to different concentrations (50-800µgmL-1) of single-walled carbon nanotubes (SWCNTs) under different levels of drought stress (0.5-1.5MPa) for 14days. Germinated seeds were subsequently allowed to grow in the same culture media for 7 more days to test the further response of the seedlings in terms of biochemical changes to the employed treatments. Seeds subjected to drought showed reduction in germination percentage, vigor and lengths of roots and shoots. However, inclusion of SWCNTs at the two lowest concentrations significantly alleviated the drought stress (up to moderate levels only)-induced reduction in germination and growth attributes. This happened due to increased water uptake, up-regulation of mechanisms involved in starch hydrolysis, and reduction in oxidative injury indices including H2O2, malondialdehyde contents and electrolyte leakage. The improved plant performance under PEG-induced drought stress was a consequence of changes in the expression of various antioxidant enzymes including SOD, POD, CAT, and APX, and also biosynthesis of proteins, phenolics, and specific metabolites such as proline. Results demonstrate that treatment by low concentrations of SWCNTs can induce tolerance in seedlings against low to moderate levels of drought through enhancing water uptake and activating plant defense system.

Evaluation of genetic variability, rust resistance and marker-detection in cultivated Artemisia dracunculus from Iran.

Artemisia dracunculus L. (tarragon), a small shrubby perennial herb, is cultivated for the use of its aromatic leaves in seasoning, salads, etc., and in the preparation of tarragon vinegar. In the present work, genetic analysis of 29 cultivated individuals of this species was carried out employing 12 ISSR and 11 SRAP markers. A total of 59 (71.64%) and 79 (83.14%) polymorphic bands were detected by 12 ISSR primers and 11 SRAP primer pairs, respectively. High similarity for patterns of genetic diversity and clustering of individuals was observed using two ISSR and SRAP marker systems and combined data. Range of genetic similarity by ISSR markers was 0.14 to 0.95, by SRAP markers was 0.14 to 0.90, while this range varied from 0.18 to 0.91 by ISSR+SRAP. In the UPGMA cluster analysis (ISSR, SRAP and ISSR+SRAP), we always found two clusters, the first cluster included 22 individuals and the second contained seven individuals. The results demonstrated that both ISSR and SRAP methods were suitable for discriminating among the studied individuals and the SRAP markers were more efficient and preferable. The results of multiple regression analysis revealed statistically significant association between rust resistance and some molecular markers that they can provide clues for identification of the individuals with higher rust resistance. The molecular marker-based study of genetic diversity suggests that the germplasm studied representing the kind of variability would be a valuable genetic resource for future breeding. In addition, in situ conservation measures are recommended to preserve the valuable A. dracunculus genetic resources as the most effective and economical approach.

The Biological Activity and Composition of the Essential Oil of Sclerorhachis leptoclada (Asteraceae-Anthemideae) from Iran.

The biological activity and composition of the essential oil of Sclerorhachis leptoclada Rech. f. an endemic species from northeast of Iran was studied. The essential oil was isolated from the aerial flowering parts of the plant and analyzed by GC and GC-MS. Fifty-four compounds accounting for 95.9% of the total oil were characterized. The main constituents were (E)-nerolidol (14.5%), terpinen-4-ol (13.3%), camphor (6.1%), 1,8-cineole (4.8%) and p-cymene (4.5%). The antimicrobial activity of the essential oil of S. leptoclada was tested against eight microbial strains and a fungi. The results of the bioassays showed that the Gram-positive bacteria, Bacillus subtilis and Staphylococcus epidermidis, were the most sensitive to the oil than others with the MIC value of 1.8 mg/mL. The tested fungi, Saccharomyces cerevisiae was highly inhibited by the oil of S. leptoclada with MIC value of 10 mg/mL. In the case of cytotoxicity, IC50 values estimated to be 312, 1250, 625 and 1250 µg oil/mL respectively, for the Vero, SW480, MCF7, and JET 3 cancer cell lines.

Population genetic structure and trait associations in forest savory using molecular, morphological and phytochemical markers.

In this investigation, morphological, phytochemical and ISSR markers were used to estimate the relationships among and within seven populations of white savory (Satureja mutica), belonging to four provinces in Iran. The individuals were phenotypically diverse, which stamen length, corolla length, corolla diameter, calyx length, bract length, inflorescence length, calyx length and bracteole width were characteristics with the highest variation. Leaf dimensions were in significant correlation with flower and inflorescence characteristics. Chemical compounds of essential oils were found variable in various individuals and all samples were principally composed of phenolic constituents (carvacrol and/or thymol). As a consequence, the plants were classified into two major chemotypes including carvacrol and thymol. A total of 197 band positions were produced by 14 ISSR primers, of which 176 were found polymorphic with 88.91% polymorphism. ISSR genetic similarity values among individuals ranged between 0.45 and 0.94 which was indicative of a high level of genetic variation. Multiple regression analysis (MRA) revealed that phytochemical compositions as dependent variable, showed statistically significant correlation and in association with leaf and flower traits as independent variable, indicating a main role of leaf and flower on production of these compounds. Also, several ISSR fragments were found associated with some morphological traits and phytochemical compositions. The high diversity within and among populations of S. mutica according to different data systems could provide useful information for conservation and selection of cross-parents in breeding programs.

Assessment of genetic and chemical variability in Thymus caramanicus.

Thymus caramanicus is an endemic species grown in Iran with interesting pharmacological and biological properties. In the present work, essential oil compositions and inter-simple sequences repeat (ISSR) markers were used to estimate the relationships among and within seven populations of T. caramanicus, belonging to three provinces in Iran. The studied individuals were distinguished on the basis of ISSR markers and constituents of essential oil. A total of 127 band positions were produced by 12 ISSR primers, of which 105 were found polymorphic with 82.68% polymorphism. Genetic similarity values among individuals ranged between 0.15 and 0.82 which was indicative of a high level of genetic variation. On the basis of their genetic similarities, ISSR analysis allowed to group the samples into two main clusters. One of these included populations originated from Kerman and Isfahan provinces, and the other cluster consists of populations from Semnan province. Chemical compounds of essential oils were found variable in the various individuals and all samples were principally composed of phenolic constituents (carvacrol and/or thymol). As a consequence, the plants were classified into two major chemotypes including carvacrol and thymol/carvacrol. A relationship between genetic and chemical variability and geographic distribution has been observed in studied populations of T. caramanicus.

Toxicity of essential oil of Satureja khuzistanica: in vitro cytotoxicity and anti-microbial activity.

In nature, essential oils play an important role in the protection of the plants by exerting anti-bacterial, -viral, -fungal, -oxidative, -genotoxic, and free radical scavenging properties, as well as in some cases acting as insecticides. Several Satureja species are used in traditional medicine due to recognized therapeutic properties, namely anti-microbial and cytotoxic activities. The purpose of the present work was to determine the biologic activity of the essential oil of S. khuzistanica Jamzad (Lamiaceae) against four human cancer cell lines, as well as its inhibitory effects against a wide array (i.e. n = 11) of pathogenic bacteria and fungi. The essential oil was isolated by hydro-distillation and analyzed by GC-FID and GC-MS. Carvacrol (92.87%) and limonene (1.2%) were found to be the main components of the isolated oil. Anti-microbial activity of the essential oil was assessed using a disc diffusion method; an MTT cytotoxicity assay was employed to test effects of the oil on each cancer cell line. The oil exhibited considerable anti-microbial activity against the majority of the tested bacteria and fungi. The test oil also significantly reduced cell viability of Vero, SW480, MCF7, and JET 3 cells in a dose-dependent manner, with the IC50 values calculated for each cell type being, respectively, 31.2, 62.5, 125, and 125 µg/ml. Based on the findings, it is concluded that the essential oil of S. khuzistanica and its major constituents have a potential for further use in anti-bacterial and anti-cancer applications, pending far more extensive testing of toxicities in normal (i.e. primary) cells.

Correlations between genetic, morphological, and chemical diversities in a germplasm collection of the medicinal plant Origanum vulgare L.

In total, 42 accessions of Origanum vulgare L., mostly originating from Europe, were evaluated, to detect molecular, quantitative morphological, and chemotype polymorphisms and to discover possible correlations between them. Twelve traits related to morphological characteristics were measured. The components in the essential oils were identified by GC/MS analysis, and the oil contents of 18 major compounds were determined. A total of 477 molecular polymorphisms including 214 AFLP (amplified fragment length polymorphism) and 263 SAMPL (selectively amplified microsatellite polymorphic loci) were used for genotyping. Euclidean distances of morphological and chemotypic data and genetic distances (1 - Dice's similarity) of molecular markers were compared by applying Mantel tests to ascertain the congruencies between them. A relatively high correlation between chemotypic patterns and genetic markers was identified, while a lower correlation was found between the morphological and genetic matrices. Pairwise analyses of correlation among all traits showed that the stem diameter was correlated to the essential-oil yield and the carvacrol content. Cluster analysis, population inference, and principal component analysis revealed a broad genetic and chemical variation among the accessions. The knowledge of these diversities, found in this study, will allow a plant improvement of Origanum vulgare related to pharmaceutical and spice uses.

Composition and in vitro antibacterial activity of essential oils from four Satureja species growing in Iran.

The composition and in vitro antibacterial activity of essential oils from four Satureja species (S. bachtiarica, S. khuzistanica, S. mutica and S. rechingeri) growing in Iran were determined. According to the results of GC-FID and GC-MS analysis, all oil samples were principally composed of phenolic constituents (carvacrol and/or thymol) with the percentages ranging from 41.2% (S. bachtiarica) to 77.7% (S. rechingeri). Determining antibacterial activities by the disc diffusion method against two Gram-positive and two Gram-negative bacteria revealed the maximum activity against Bacillus cereus with a range of minimum inhibitory concentration values from 0.25 to 1 mg mL(-1) and minimum bactericidal concentration values from 0.5 to 1 mg mL(-1). The oils of S. khuzistanica and S. rechingeri appeared to be more active in general than those of other species. In conclusion, the essential oils of studied Satureja species have the potential to be considered as alternatives for synthetic food preservatives.

Phytochemical and morphological characterization of Satureja khuzistanica Jamzad populations from Iran.

Satureja khuzistanica is an endemic herb growing wild in Iran with interesting pharmacological and biological properties. Here, as an initial step of the domestication process, the variability of phytochemical and morphological traits among 69 individuals of eight natural populations of the plant was studied. The investigated characteristics were the essential oil content and composition, the rosmarinic acid (RA) content, and the leaf and flower morphologies. The Abdanan and Kaver populations showed the highest oil contents. The characterization by GC-FID and GC/MS analyses of the oils revealed that all 69 sampled individuals had carvacrol as the main component with very high contents (89.59-95.41%). The content of RA of the MeOH extracts of S. khuzistanica showed a high level of variability (coefficient of variation (CV) 50.0%) ranging from 0.59% (w/w) in the Paalam population to 1.81% (w/w) in the Abdanan population. The peduncle length and the leaf surface area (CVs of 47.39 and 47.21%, resp.) were the most variable morphological characteristics among the examined populations. The high level of phytochemical and morphological variability among the studied populations suggests a breeding approach during the domestication, to gain new, promising, and homogenous cultivars, attractive for the industry and agriculture.

Chemical and genetic diversity of Zataria multiflora Boiss. accessions growing wild in Iran.

Zataria multiflora Boiss. is an aromatic shrub belonging to the Lamiaceae family. Its aerial parts are used in the traditional medicine and in the pharmaceutical and food industries. The terpenoid and genetic profiles of 18 accessions of Z. multiflora, collected in different locations in Iran, have been analyzed by GC/FID and GC/MS or by AFLP (amplified fragment length polymorphism) analyses, respectively. Altogether, 56 compounds were identified in the essential oils, with the major constituents being thymol (6.0-54.9%), carvacrol (0.7-50.6%), linalool (1.2-46.8%), and p-cymene (1.6-14.8%). On the basis of the essential-oil composition, the 18 accessions were divided into four groups. The first group was characterized by a high content of carvacrol, thymol, and linalool, the second group was dominated by carvacrol, thymol, and p-cymene, the third group was characterized by a high concentration of thymol and a low content of carvacrol and p-cymene, and the forth group contained linalool and carvacrol as the main components. The AFLP results revealed that the average genetic similarity (GS) between the accessions was 0.61, ranging from 0.40 to 0.77. The UPGMA (unweighted pair-group method with arithmetic mean) cluster analysis divided all accessions into five groups at a similarity level of 0.60. The two clusters generated, the first based on the essential-oil compositions and the second on the AFLP data, showed a different pattern of relationships among the accessions. The knowledge of the Z. multiflora chemotype diversity, illustrated in this study, will allow an improvement of the homogeneity of the plant material for the production of different types of essential oils, depending on the demands of the pharmaceutical and food industries for specific uses.