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Foods provide a natural and perfect medium for bacteria and fungi to multiply and growth. Awareness of people of synthetic additives and preservatives in food processing has led food industries to search for natural additives with a broad spectrum of antimicrobial activities. The chemical compositions of the essential oils (EOs) distilled from three Satureja spp. have been analyzed by gas chromatography-mass spectrometry (GC-MS). The antimicrobial activities of the EOs against microorganisms causing food-borne infections were determined by the broth micro-dilution method as recommended by the Clinical and Laboratory Standards Institute (CLSI). Analysis of the EOs showed that phenolic compound including thymol and carvacrol are the main components of the EOs. Inhibition studies indicated that the tested EOs entirely inhibited the growth of tested fungi at concentrations of less than 0.062 μl/mL. Moreover, the oils exhibited significant bacteriostatic and bactericidal activities against Gram-positiv...

Changes of essential oil (EO) compositions of Myrtus communis were determined for a period of 3 months storage in refrigerator (4°C), freezer (-20°C), and at room temperature. The quantities of lower boiling temperature compounds such as α-pinene (30.8- 0.0 %), limonene (31.4- 0.1 %) and 1,8-cineole (22.3- 1.2 %) as α-terpinene precursors, were decreased at room temperature. However, the concentrations of α-terpineol and geranyl acetate considerably enhanced by 27 and 25 % after 3 months, respectively. Increasing of α-terpineol and geranyl acetate by storage at room temperature improve the oil quality index. Furthermore, when the oil stored at freezing temperature (-20°C.), represented its original quality at the extraction time with minimum changes.

An investigation was conducted to study the chemical diversities among 44 accessions of Damask rose (Rosa damascena Mill.) essential oils collected in Iran. Gas chromatography (GC) and GC/mass spectrometry (GC-MS) were employed to determine the chemical compositions of essential oils which were hydro-distilled from flowers at full bloom stage. Results showed that the essential oils of these accessions had considerable variabilities for major and minor components. Cluster analysis, based on oil compositions, was used to classify studied accessions. It was shown that these 44 accessions of Damask rose had five distinct chemotypes namely citronellol (18.8-45.8 %), geraniol (37.5-41.4 %), neral (23.2-44.8 %), Dihydro-linalool (30.5-59.2 %), and n-nonadecane (20.6-55.4 %).

Denaei Thyme (Thymus daenensis Celak.) is a perennial plant from Lamiaceae family. The plant's leaves possess biological attributes that provide it with the potential to be used for medicinal purposes and newly for suppressing the growth of herbaceous plants. In this study essential oil (EO) compositions and phytotoxic effects of four T. deanensis ecotypes (ECTPs) of T. deanensis were evaluated on Amaranthus retroflexus, Avena fatua, Datura stramonium and Lepidium sativum germination and related growth traits.For this purpose, thyme plants were collected from different ecological locations of Fars Province, Iran to identify EOs content and compositions and also their phytotoxic activity. Gas chromatography (GC) and GC-Mass spectrometry (GC-MS) analysis of the EOs showed that thymol (20 - 60.5 %) and carvacrol (20.1 - 63.4 %) were the two major oil components found in the studied ECTPs. For evaluating phytotoxic activity, the concentrations, 0, 200, 400, 600, 800 and 1000 µl l-1 of the EOs were tes...

Salicylic acid (SA) is a naturally occurring plant hormone influencing various physiological and biochemical functions in plants. This investigation was conducted to evaluate the effects of different concentrations (0, 75, 150, 300, 450 mgL-1) of salicylic acid (SA) on the essential oil (EO) content and compositions of peppermint (Mentha piperita L.). The results showed that application of 150 mgL-1 SA significantly (p

The chemical compositions of floral scent from two distinct genotypes (G1 and G2) of Iranian Rosa damascena flowers were isolated at six stages of flower development using headspace extraction. The main floral headspace components were phenyl ethyl alcohol, β-citronellol, α-pinene, benzyl alcohol and geranyl acetate. In both genotypes, the relative percentage of phenyl ethyl alcohol increased as flowers were developed. However, the concentration of β-citronellol was highest in stage 4 (47 %) and stage 3 (45.1 %) in two genotypes under study. The first flower development stage of both genotypes had the lowest amount of this compound. Benzyl alcohol was highest and a major component in the G2 and increased with floral development while G1 had a trace amount of this compound. Geranyl acetate, an important contributors to the aroma, was highest in stage 4 (11.6 %) and stage 3 (22.7 %) in the G1 and G2, respectively. This compound was not found in early stages of flowers development (stages 1 and 2) of...

A Pot experiment was carried out to determine the effects of foliar application of diammonium phosphate on the quantity and quality of essential oil (EO) of Mexican marigold (Tagetes minuta L.), an important medicinal plant. Diammonium phosphate was applied at the rates of 0, 2.4, 4.8, 7.2, 9.6, and 12 at three stages of plant growth (i.e. stem formation, two weeks later and at floral budding). Results indicated that EO content increased with increasing diammonium phosphate levels up to 7.2 %. A foliar spray of 7.2 enhanced the biosynthesis of EO to the extent of 0.50 % over the control, however, no significant differences were found between 7.2, 9.6, and 12 % diammonium phosphate on EO content. The results of EO analysis showed that the amounts of dihydro tagetone (62.5 – 74.6 %) and Z-tagetone (9 – 11.2 %) as two major oil components increased gradually with increasing diammonium phosphate levels, however, the amounts of Z-β-ocimene (12.9 – 7 %) and Z-ocimenone (4.5 – 1.8 %) decreased with incr...

The variations in content and compositions of catnip (Nepeta cataria) essential oil were examined at different developmental stages (i.e. vegetative, floral budding, full flowering, and fruit set). The essential oil of the plant was extracted by hydrodistillation. The yield of essential oils (w/w %) were 0.3, 0.5, 0.9, and 0.4 % at vegetative, floral budding, full flowering, and fruit set stages, respectively. The essential oils were analyzed by GC and GC-MS. A total of 13, 12, 14, and 11 components were identified and quantified at the above mentioned stages, respectively. The essential oil content showed significant increase at full flowering stage. Three components, 4a-α,7-α,7a-β-nepetalactone (55 - 59 %), 4a-α,7-β,7a-α-nepetalactone (30 - 31.2 %), and α-pinene (2.7 - 4.6%) were the major oil constituents of all growth stages. The proportions of 4a-α,7-α,7a-β-nepetalactone and α4a-α,7-β,7a-α-nepetalactone, as major oil constituents were highest at fruit set and full flowering stages, respectively.

This study was carried out at Sadra Experiment Station, Shiraz, Iran to determine the changes in the content and chemical compositions of essential oil from fennel fruits at three different growth stages including pasty, waxy, and full ripening containing 70, 52, and 10 % moisture, respectively. The essential oils of dried fruits were extracted by hydrodistillation method using Clevenger apparatus, and analyzed by GC and GC-MS. The essential oil content of fruits were 1.31, 1.18, and 1.26 %, at pasty, waxy and full ripening stages, respectively. The main oil components at different fruit maturity stages were found to be trans-anethol (84.1 -86.1 %), fenechone (7.13 – 8.86 %), limonene (3.0 – 3.3 %), and methyl chavicol (2.5 – 2.7 %).

Echinophora platyloba is a valuable essential oil bearing plant. The variation in the quantity and quality of the essential oil of wild populations of E. platyloba extracted by hydro distillation was studied during different growth and developmental stages. The content of essential oils (w/w %) were 0.7, 0.5, and 0.2 % in rosette, floral budding, and full flowering stages, respectively. The essential oils were analyzed by GC and GC-MS. Total of 41, 62, and 56 components were identified and quantified in the above mentioned stages, respectively. The oil content showed remarkable increase at rosette stage. The proportion of (Z)-β-Ocimene, as a major component at rosette, drastically decreased in floral budding and then slightly increased at full flowering stage. In contrast, (E)- β-ocimene was not detected at the rosette stage but was the major component at the subsequent harvest time and then decreased at full flowering stage. Moreover, monoterpene hydrocarbons were the main group of compounds in ...

Field trials were carried out in a semi-arid climatic area in Iran in the years of 2004 and 2005 to determine the effect of phosphorus fertilizer and irrigation treatments on the essential oil content and composition of feverfew (Tanacetum parthenium L. cv. Zardband). Phosphorus fertilizer was band-placed at the rates of 0 (P0), 50 (P1), 100 (P2) and 150 (P3) Kg/ha at planting and irrigation treatments were applied at 10 (I1), 20 (I2) and 40 (I3) mm per week. The essential oil was obtained by hydro- distillation from the herb of the plant and then was analysed by using GC and GC-MS. According to the results phosphorus fertilizer and irrigation treatments had important role on the essential oil content and composition of feverfew. Application of phosphorus significantly increased the essential oil content and as well as camphor and chrysanthenyl-acetate. I1 P 3 (10 mm/week irrigation and 150kg/ ha P) treatment produced the highest amount of essential oil and camphor and I2 P3 (20 mm/week irrigatio...

The fruits of Ajowan (Trachyspermum ammi) cultivated in Iran were harvested at pasty (unripe) and ripening stages with 54% and 5% moisture, respectively. The essential oils of fruits were extracted by hydrodistillation technique and were analyzed by capillary GC and GC/MS. The essential oil content of fruits harvested at pasty and ripe stages were 7.1% (w/w) and 3.2% (w/w) based on dry weight respectively. Ten and twelve components have been identified in the oils of pasty and ripe fruits respectively. The major components of the oil of pasty stage harvested fruits were γ-terpinene (43.2%), Thymol (32.4%) and p-cymene (20.7%) while the main components of the oil of ripe fruits were thymol (36.7%), γ-terpinene (36.5%) and p-cymene (21.1%).

The essential oil content and chemical composition of Pimpinella anisum fruit was determined at different harvesting times of waxy (with 26 to 28% moisture ) and ripening stages. The essential oil was obtained by hydro distillation of fruits, and was analyzed by GC and GC-MS. The oil content of fruits harvested at waxy (unripe) and ripe stages were 5.5% and 3.4 % respectively. Eight and eleven components have been identified in the oils of waxy and ripe fruits respectively. The major components of the oil of waxy stage were (E)-anethole (90.35%), estragole (3.6%), eugenyl acetate (3.34%) and the main components of the oil of ripe fruit were, (E)-anethole (80.7%), eugenyl acetate (3.92%), γ-himachalene (3.52%), estragole (2.27%) and α-zingiberene (1.9%).