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The leaf essential oil yields of clementine, cypress, rosemary, tea, and thyme were 0.22, 0.87, 1.46, 1.20, and 0.72%, respectively, based on the dry weight of the plant material. The leaf essential oils of rosemary, tea, and thyme contained the highest levels of oxygenated monoterpenes (60.14-91.70%). Rosemary and tea leaf essential oils were rich in 1,8-cineole (49.98% and 57.55%, respectively), and they have potent antifungal activity against Alternaria alternata strain (MIC = 5000 μg/ml). Thyme was rich in carvacrol (78.54%) and had a MIC of 6000 μg/ml against A. alternata strain. Clementine leaf essential oil was characterized by the predominance of monoterpene hydrocarbons (88.65%), and it possessed a weak antifungal activity against A. alternata (MIC = 8000 μg/ml). Cypress leaf essential oil was characterized by the predominance of oxygenated sesquiterpenes (60.67%), having an antifungal activity of 8000 μg/ml. [ABSTRACT FROM AUTHOR]

The intention of this study was to compare the different parts of Tunisian Ferula communis via their fatty acids, essential oils and phenolic compounds. Results showed that the lipid fraction of fruits and leaves was characterized by the predominance of oleic acid. Erucic and linoleic acids were the most abundant in stems while linoleic and palmitic acids in flowers. F. communis essential oils were defined by four chemotypes, namely isoshyobunone/6-tert-butyl-4-methylcoumarin in stems; α-eudesmol/caryophyllene oxide in leaves; caryophyllene/myrcene in flowers and α-gurjunene/hexadecanoic acid in fruits. So, oxygenated sesquiterpenes and sesquiterpene hydrocarbons represented the major classes of stem essential oil. Monoterpene hydrocarbons were the predominant classes of leaves and flowers. Fruit essential oil was predominated by sesquiterpene hydrocarbons. Resorcinol and ferulic acid were the main phenolic compounds in flowers but chlorogenic and ferulic acides in leaves. Stems were rich in ferulic acid and quercetin while leaves in coumarin and tannic acid. Besides to the high variability among F. communis parts, this plant contained high amounts of bioactive compounds with various health benefits attributed to their antioxidant potential. [ABSTRACT FROM AUTHOR]

Essential oils (EOs) obtained by hydrodistillation of the dried aerial parts of two horehound species: Marrubium vulgare L. and endemic Marrubium aschersonii Magnus (family Lamiaceae), were investigated by GC and GC-MS. Thirty five components and thirty seven components were identified respectively in EO of M. vulgare and that of M. aschersonii, They accounted for 74.6% and 79.5% of the whole oils. Both EOs were characterized by high amounts of sesquiterpenes (50.5% and 37.7%). β-bisabolene (28.3%), β- caryophyllene (7.8%), (E)-β-farnesene (7.4%) and 1,8-cineole (4.8%) were the major constituents of M. vulgare oil, while β-bisabolene (22.0%), a-thujene (10.3%), eugenol (10.1%), a-humulene (6.2%) were the major constituents of M. aschersonii oil. [ABSTRACT FROM AUTHOR]

This study was designed to examine the essential oil composition, phenolic contents and antioxidant activity of the essential oils and methanol extracts from two coriander fruit samples, the first from Tunisia (Tn) and the second from Canada (Can). The highest essential oil yield was observed for Can with 0.44% (w/w) and 0.37% (w/w) for Tn. Forty-five compounds were identified in the essential oils and the main compound of both samples was linalool. The total phenol contents varied between two coriander fruit samples; Can sample presented high polyphenol contents (15.16 mg GAE/g) compared with Tn one (12.10 mg GAE/g). Significant differences were also found in total tannin contents among representing 0.7 mg GAE/g in Can and 0.34 mg GAE/g in Tn. The highest contents of total flavonoids were observed in Can sample with 13.2 mg CE/g. Antioxidants of essential oils and methanolic extracts of these fruit samples were evaluated by using DPPH radical scavenging, β-carotene-linoleic acid bleaching and reducing power activity assays. In all tests, methanolic extracts of coriander fruits showed better antioxidant activity than essential oils. DPPH scavenging ability of methanolic extracts of two fruits was higher than that of synthetic antioxidant BHT (IC50 = 25 µg/mL). Both extracts and essential oils had lower β-carotene bleaching activity than BHA and BHT and had lower reducing power than ascorbic acid (EC50 = 40 µg/mL). [ABSTRACT FROM AUTHOR]

Myrtus communis var. italica leaves, fruits and stems were gathered from North Tunisia in order to investigate their essential oils during a one-year vegetative cycle by GC-FID and GC/MS. The yield and composition of myrtle oils were found to depend on the organ type and on the harvest period. The oil yield varied from 0.14-0.61% for the leaves, 0.003-0.11% for the fruits, and 0.001-0.06% for the stems. Forty-eight compounds were identified in leaf oils; α-pinene (28.3-58.0%), 1,8-cineole (12.7-30.7%), linalool (2.4-21.5%) and limonene (0.1-13.3%) were the main components. In the fruit oils, 46 compounds were identified with 1,8-cineole (7.3-44.9%), geranyl acetate (1.8-20.5%), linalool (0.7-18.9%) and α-pinene (1.2-12.6%) being the main compounds. Only 40 components were identified in stem oils, which were rich in 1,8-cineole (21.0-52.4%), linalool (3.1-18.4%) and α-pinene (1.5-16.1%). [ABSTRACT FROM AUTHOR]

Gas chromatography–mass spectrometry analysis of seed Borago officinalis essential oil (EO) revealed the presence of 16 volatile components. β-Caryophyllene (26%) and p-cymene-8-ol (19.7%) represented the major components, while nonadecane (0.7%) and hexanol (0.7%) were the minor ones. The EO composition was characterized by higher abundance of oxygenated monoterpenes (27.7%), followed by sesquiterpenes (26%). Fatty acid composition showed the predominance of linoleic (35.4%), oleic (24.2%) and γ-linolenic (20.4%) acids. Polyphenols were analyzed by reversed-phase high-performance liquid chromatography after acid hydrolysis of phenolic acid esters. Six phenolic acids were identified in seed extract and rosmarinic acid was the predominant one with 1.65 mg/g dry matter weight equivalent to 33% of total phenolic acids. PRACTICAL APPLICATIONS Borage ( Borago officinalis L.) is of great interest because of its medicinal and nutritional properties. In fact, thanks to its characteristic composition in fatty acids, particularly high levels of gamma-linolenic acid in its seed oil, borage has gained importance. The potent consumers of this medicinal plant are hypertensive and hypercholesterolemic people. Borage consumption is also recommended for people suffering from rheumatism and eczema. Unfortunately, the knowledge about antioxidative/antiradical properties of borage is very scanty. So, recently, an extensive investigation was focused on the antioxidant properties of borage extracts. These extracts showed excellent antioxidant properties and their effects were attributed to their phenolic constituents. These antioxidants can be concentrated, either as crude extracts or individual phenolic compounds, to be used in highly unsaturated oils such as marine oils. Furthermore, borage consumption has been reported as a possible gastric cancer protective factor. [ABSTRACT FROM AUTHOR]