Essential oil variation in the populations of Artemisia spicigera from northwest of Iran: chemical composition and antibacterial activity.

CONTEXT: Artemisia spicigera C. Koch (Asteraceae) is a perennial shrubby herb and is generally distributed in Armenia, Iran, and Middle Anatolia. This species traditionally has been used in medicines. OBJECTIVE: The aim of this research is to study the chemical composition and antibacterial activity of essential oils from Artemisia spicigera populations in northwest of Iran. MATERIALS AND METHODS: The essential oil of A. spicigera was obtained by hydrodistillation from eight populations collected from different regions of East Azerbaijan and West Azerbaijan provinces (Iran) and analyzed by gas chromatography-mass spectrometry (GC-MS). The antibacterial activity of the oils was investigated against four Gram-positive and four Gram-negative bacteria using MIC determinations and the agar-gel diffusion method. RESULTS: Fourteen compounds were identified as the main components of the essential oils and the most abundant constituents are 1,8-cineole, camphor, α-thujone, camphene, ß-thujone and p-cymene. Essential oil of population No. 1 showed the highest activity against Escherichia coli, Enterobacter aerogenes, Serratia marcescens and Staphylococcus aureus but the highest activity against St. saprophyticus, Bacillus megaterium, and B. cereus was found with population No. 6 and for Citrobacter amalonaficus with population No. 5. MIC values of essential oils ranged from 6 µg/mL against Bacillus megaterium to 12 µg/mL against Citrobacter amalonaficus. DISCUSSION: This study demonstrates the occurrence of 1,8-cineole/camphor/camphene chemotype of A. spicigera but there is also significant chemical variation between the studied populations. The findings showed the studied oils have good antibacterial activity, and thus potential to be used as natural health products.

Effect of the heavy metals on developmental stages of ovule, pollen, and root proteins in Reseda lutea L. (Resedaceae).

Heavy metals are some of the most important environmental pollutants. Excessive amounts of heavy metals adversely affect plant growth and development. Also, the presence of elevated levels of heavy metal ions triggers a wide range of cellular responses including changes in gene expression and synthesis of metal-detoxifying peptides. The overall objective of this research was to elucidate some microscopic effects of heavy metals on the formation, development, and structure of pollen, ovule, and embryo and also root proteins in Reseda lutea L. For this purpose, the vicinity of Ahangaran lead-zinc mine (Hamedan, Iran) was chosen as a polluted area where amount of some heavy metals was several times higher than the natural soils. Flowers and young buds were collected from non-polluted and polluted plants, fixed in FAA(70), and studied during developmental stages by light microscopy. The results showed that heavy metals can cause some abnormalities during the pollen and ovule developmental process. The number of pollen grains was decreased, and their shape was changed. Increasing in thickness of the callosic wall and stabilizing of tapetum layer were observed in polluted plants. Asymmetrical formation of ovular integuments, degradation of egg apparatus, irregular formation of embryo sac, considerable vacuolation of embryonic cells, and degeneration of embryo in the late stage of heart-shaped embryo are the results of heavy metal pollution. For protein studies, young roots were harvested from plants exposed to pollution and non-exposed to pollution at the same time. Root proteins were extracted and studied by electrophoresis. The results revealed that some new proteins were synthesized in polluted samples that probably elevate plant tolerance to heavy metals.

Investigating the effect of heavy metals on developmental stages of anther and pollen in Chenopodium botrys L. (Chenopodiaceae).

Excessive amounts of heavy metals adversely affect plant growth and development. Whereas some regions naturally contain high levels of heavy metals, anthropogenic release of heavy metals into the environment continuously increases soil contamination. Preliminary studies have shown that Chenopodium botrys can grow in some heavy metal contaminated soils and is a high accumulator plant species for Cu and moderately accumulator plant species for Fe, Mn, and Zn, thus, was considered as an important species in this study. Based on that, in this species, we studied the individual effects of heavy metals on the formation, development, and structure of anther and pollen. To achieve this purpose, surrounding area of Hame-Kasi iron and copper mine (Hamedan, Iran) was chosen as a polluted area where the amount of some heavy metals was several times higher than the natural soils. Flowers and young pods were removed from non-polluted and polluted plants, fixed in FAA 70, and subjected to developmental studies. Analysis of anther development in plants from contaminated sites showed general similarities in the pattern of pollen formation with those from non-polluted ones, but also deviation from typical form of major stages of anther and pollen development was seen in plants from polluted ones. Stabilizing of tapetum layer, increasing in tapetum layer numbers, thickening callose wall in the microspore mother cell stage, changing the anther shape, and decreasing the size of anther were the effects of heavy metals. Reduction of pollen number was also seen in the plants collected from polluted area.

Chemical composition and antibacterial activity of essential oils of Tripleurospermum disciforme in three developmental stages.

CONTEXT: Tripleurospermum disciforme (C.A. Mey) Schultz Bip. (Asteraceae) is a widespread biennial species which also has traditional medicinal uses. According to the few recent studies, essential oils of this species exhibit anti-inflammatory, antispasmodic, antiseptic, antifungal, antiulcer, and antioxidant activity. OBJECTIVE: The chemical compositions of the hydrodistilled oils of T. disciforme of Iranian origin are studied in the stages of prior to flowering, flowering, and post flowering, for the first time. Also, we investigated the antibacterial activities of the oils. MATERIALS AND METHODS: The essential oils of air-dried T. disciforme were obtained by hydrodistillation in three different developmental stages and analyzed by gas chromatography-mass spectrometry (GC-MS). The antimicrobial activity of the isolated essential oil, in the three stages, was also investigated against four Gram-positive and four Gram-negative bacteria. RESULTS: Twenty-one components were identified in the essential oils of T. disciforme, and the highest amount of oil was extracted at the flowering stage. The main component of the species in the flowering stage was ß-farnesene (22.46%) and the other major components were ß-sesquiphellandrene (17.85%), p-methoxy-ß-cyclopropylstyrene (16.64%), heptadecane (10.6%), p-methoxy-humulene oxide (6.88%) and benzene acetaldehyde (9.3%). The MIC of essential oil was evaluated from 4 µL ml(-1) against Staphylococcus subtilis and Bacillus cereus to 22 µL ml(-1) against Citrobacter amalonaticus. DISCUSSION AND CONCLUSION: This study demonstrates the occurrence of ß-farnesene/ß-sesquiphellandrene chemotype of T. disciforme in western regions of Iran that are different from previous reports. The findings also showed that the essential oils T. disciforme have excellent antibacterial activities and thus have great potentiality to be used as a resource for natural health products.

Phytoremediation of petroleum-polluted soils: application of Polygonum aviculare and its root-associated (penetrated) fungal strains for bioremediation of petroleum-polluted soils.

Petroleum-polluted soils are a common disaster in many countries. Bioremediation of oil contamination in soils is based on the stimulation of petroleum-hydrocarbon-degrading fungal and microbial communities. A field study was conducted in a petroleum-contaminated site to find petroleum-resistant plants and their root-associated fungal strains for use in bioremediation of petroleum-polluted soils. Results and observations showed that the amounts of petroleum pollution in nonvegetated soils were several times higher than in vegetated soils. Plants collected from petroleum-polluted areas were identified using morphological characters. Results indicated that seven plant species were growing on the contaminated sites: Alhaji cameleron L. (Fabaceae), Amaranthus retroflexus L. var. retroflexus (Amaranthaceae), Convolvulus arvensis L. (Convolvulaceae), Chrozophora hierosolymitana Spreg. (Euphorbiaceae), Noea mucronata L. (Boraginaceae), Poa sp. (Poaceae), and Polygonum aviculare L. (Polygonaceae). The root-associated fungi of each plant were determined and results showed the presence of 11 species that associated with and also penetrated the roots of plants growing in the polluted areas. Altenaria sp. was common to all of the plants and the others had species-specific distribution within the plants. The largest numbers of fungal species (six) were determined for P. aviculare and Poa sp. in polluted areas. However, the variation of fungal strains in the plants collected from petroleum-polluted areas was greater than for nonpolluted ones. Culture of fungi in oil-contaminated media showed that all the studied fungi were resistant to low petroleum pollution (1% v/v) and a few species, especially Fusarium species, showed resistance to higher petroleum pollution (10% v/v) and may be suitable for bioremediation in highly polluted areas. Bioremediation tests with P. aviculare, with and without fungal strains, showed that application of both the plant and its root-associated fungal strains was more effective than of the plant and fungi separately, and Fusarium species were the most effective. Results indicated that fungal strains had the main role in bioremediation of petroleum-polluted soils, but plant roots enhanced the process.

Diesel exhaust particles and allergenicity of pollen grains of Lilium martagon.

Diesel exhaust particles are considered as the most important parts of air pollutants. Diesel exhaust particles have been shown to express both adjuvant activity for sensitization against common allergens and enhancing effects on allergic symptoms in sensitized individuals. In this research, pollen grains of Lilium martagon that are known as a non-allergic substance were collected and exposed to DEP 5 and 10 days. The allergy potency of different pollen extracts were compared by means of skin test, as well as analyses blood eosinophil numbers and IgE levels in the treated animals. Normal and DEP-exposed pollen grains were examined by scanning electron microscopy. Pollen extracts were also studied by SDS-PAGE for DEP-induced changes in protein profiles. Allergic bands were also studied and checked by using immunoblotting method. The results of the investigated allergy tests showed that DEP-exposed pollen grains are effective in inducing allergic symptoms. According to our microscopic observations, organic substances that exist in the DEP, mediate agglomeration of particles on the pollen surface. In appropriate conditions, water-soluble components of DEP may induce changes that affect the release of pollen proteins. SDS-PAGE showed protein profiles of pollen grains were changed and some new bands appeared in DEP-exposed pollen grains. Immunoblotting studies showed a new band in DEP-exposed pollen grains that react strongly with anti-IgE, but there is no allergenic band in normal pollen grains. On the other hand, diesel exhaust particles can carry pollen allergen molecules, induce new proteins (allergens), and also act as adjuvant for allergens.

Increasing allergy potency of Zinnia pollen grains in polluted areas.

There is much evidence that allergic symptoms represent a major health problem in polluted cities. The aim of this research is to elucidate some microscopic effects of air pollutants on pollen structure, proteins, and allergenicity. A scanning electron microscopy study of pollen grains indicated that in polluted areas, airborne particles accumulate on the surface of pollen grains and change the shape and tectum of pollen. Also, many vesicles are released from polluted pollen grains and the pollen material agglomerates on the surface of pollen grains. SDS-PAGE revealed that different proteins exist in mature and immature pollen grains. There were no significant differences between protein bands of polluted and nonpolluted pollen grains, but in polluted pollen, protein content decreases in response to air pollution, causing the release of pollen proteins. The results indicate that mature pollen have more allergenicity than immature pollen. According to the experiments polluted pollen grains are more effective than nonpolluted pollen grains in inducing allergic symptoms. Air pollutants can cause allergic symptoms, but when associated with allergen pollen grains, their allergenicity power is increased.