Does unsaponifiable fraction of grape seed oil attenuate nitric oxide production, oxidant and cytotoxicity activities.

Triterpenoids, tocopherols, and phytosterols presented in unsaponifiable fraction of grape seed oil have several beneficial effects comprising antioxidant, anti-inflammatory, and antitumor capacities. In this study, the unsaponifiable fraction of three Tunisian grape seed varieties (Vitis vinifera L.), namely Merlot, Carignan, and Syrah, was investigated. The identified compounds were two triterpenic compounds (ß-amyrin, lanosterol), six phytosterols (campesterol, ∆7 -avenasterol, stigmasterol, ß-sitosterol, ß-sitostanol, cholesterol), and three tocopherols (α, ß, and γ tocopherols). The unsaponifiable fraction had significant protection against oxidative damage by modulating NO production and antioxidant activity. Statistical analysis showed the presence of three clusters of varieties associated to specific composition patterns. These results clearly demonstrated that unsaponifiable fraction profiles of grape species could be considered as a complementary data to the existing taxonomic evidence and classification purposes. PRACTICAL APPLICATIONS: Recently, much attention has been focused to substitute artificial antioxidant by others originating from natural products as plant matrices. The unsaponifiable fraction of grape seed oils is an interesting source of bioactive components like phytosterols, tocopherols, triterpenoids, and other various components. These components are known for their antitumor, anti-inflammatory and antioxidant capacities.

Chemical composition and antioxidant potential of essential oil and methanol extract from Tunisian and French fennel (Foeniculum vulgare Mill.) seeds.

This study was designed to examine the effect of provenance on the phytochemical and antioxidant properties of essential oil and methanolic extract from Tunisian and French fennel seeds (FFS). Analysis of the essential oil showed that although the same main compounds were found in Tunisian and FFS cultivars, some differences were present in their proportions allowing to classify them in two chemotypes. The first class was composed by trans-anethole (63.41%-78.26%) for Tunisian cultivars and the second one by estragole (44.72%-88.92%) for French cultivars. The phenolic composition of all fennel seed extracts was characterized by its richness in quinic acid, 4-O-caffeoylquinic acid, p-coumaric acid, and 4-O-caffeoylquinic acid. All fennel seed extracts showed a better antioxidant potential than their essential oils depending on the origin. Principal component analysis showed a dispersion of the cultivars on three groups depending on the chemotype diversity. PRACTICAL APPLICATIONS: Recently, much attention has been focused on fennel due to the nutritional and health-protective value of their seeds. Several studies have highlighted the importance of fennel seed extracts and essential oils as key ingredients rich in bioactive compounds serving in formulation of new functional food products. This investigation designed to examine the effect of provenance on phytochemical and antioxidant potentials of Tunisian and French fennel seed extracts and essential oils.

Antidiabetic, antihyperlipidemic and antioxidant influences of the spice cinnamon ( Cinnamomum zeylanicumon ) in experimental rats

ABSTRACT The present study investigates the effect of cinnamon (Cinnamomum zeylanicumon) powder supplementation on glucose levels, lipid profiles, and oxidative stress parameters in alloxan-induced diabetic rats. Diabetes was induced in adult male Wistar rats via a single subcutaneous alloxan injection (15 mg/kg). Cinnamon powder was mixed with the standard feed of the rats in an amount of 5% for 28 consecutive days. Serum concentrations of total cholesterol (TC) and triglycerides (TG) were assayed at the end of the experimental period in all investigated groups. Anti-oxidative enzymes such as glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) were sought in the serum and pancreas. Alloxan caused the fasting blood sugar level to increase. The administration of cinnamon blocked the increase of blood glucose. There was also a significant difference in the TG and TC levels between control and treated diabetic rats. In diabetic rats, cinnamon treatment restored the activities of SOD, CAT and GPx. These findings suggested that cinnamon has an anti-hyperglycemic effect, improves lipid profiles, and protect against damage induced by oxidative stress in the diabetic state.

Characterization of myrtle seed (Myrtus communis var. baetica) as a source of lipids, phenolics, and antioxidant activities.

This study aimed to characterize the chemical composition and antioxidant activity of the oil and the methanolic extract of Myrtus communis var. baetica seed. The oil yield of myrtle seed was 8.90%, with the amount of neutral lipid, especially triacylglycerol, being the highest, followed by phospholipids and glycolipids. Total lipids and all lipid classes were rich in linoleic acid. The content of total phenols, flavonoids, tannins, and proanthocyanidins of the methanolic extract and the oil from myrtle seed was determined using spectrophotometric methods. Antioxidant activities of the oil and the methanolic extract from myrtle seed were evaluated using 1,1-diphenyl-2-picrylhydrazyl radical scavenging, ß-carotene-linoleic acid bleaching, and reducing power and metal chelating activity assays. In all tests, the methanolic extract of myrtle seed showed better antioxidant activity than oil. This investigation could suggest the use of myrtle seed in food, industrial, and biomedical applications for its potential metabolites and antioxidant abilities.

Juice components and antioxidant capacity of four Tunisian Citrus varieties.

BACKGROUND: Juices from four Citrus species of Tunisia were investigated mainly for quality parameters and antioxidant capacity. RESULTS: Citrus reticulata (mandarin) juice had the highest content of total flavonoids (85.33 mg CE L(-1)). The latter also occurred in high quantity (82.01 mg CE L(-1)) in Citrus lemon (lemon) juice which was also marked by its richness in total aroma (70.16 µg mL(-1)) and in total fatty acids (48.10 µg mL(-1)). Mandarin and lemon juices had the highest antioxidant activity, as determined b the ß-carotene bleaching assay (26.67% and 22.67%, respectively). Citrus aurantium (bitter orange) juice was characterised by the highest content of total polyphenols (784.67 mg GAE L(-1)) and by the greatest inhibition of DPPH (96.10%). Citrus sinensis (blood orange) juice was only marked by the high quantity of ascorbic acid (36.90 mg mL(-1)). GC/MS analysis of juice aroma showed the predominance of limonene (48.85-69.59%) in mandarin and in bitter and blood oranges, but of camphene (89.05%) in lemon. GC analysis of juice fatty acids revealed their richness in oleic acid (23.13-39.52%). HPLC analysis of juice phenolics indicated the predominance of phenolic acids (73.13-86.40%). CONCLUSION: The Citrus species used in this study were considered valuable varieties from the point of view of antioxidant capacity and nutrition.

Essential oils, phenolics, and antioxidant activities of different parts of cumin (Cuminum cyminum L.).

Cuminum cyminum L. roots, stems and leaves, and flowers were investigated for their essential oils, total phenolics, flavonoids, and tannins contents, individual phenolic compounds, and antioxidant activities. The essential oil was investigated by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), whereas identification and quantification of individual target polyphenolic compounds was performed by reversed-phase high-performance liquid chromatography (RP-HPLC). Essential oil yields were 0.03% in roots, 0.1% in stem and leaves, and 1.7% in flowers. Major components of the oils were bornyl acetate (23%), α-terpinene (34%), and γ-terpinene (51%) in roots, stems and leaves, and flowers, respectively. In all C. cyminum organs, total phenolics content ranged from 11.8 to 19.2 mg of gallic acid equivalents per gram of dry weight (mg of GAE/g of DW). Among the polyphenols studied, 13 were identified in roots, 17 in stem and leaves, and 15 in flowers. The major phenolic compound in the roots was quercetin (26%), whereas in the stems and leaves, p-coumaric, rosmarinic, trans-2-dihydrocinnamic acids and resorcinol were predominant. In the flowers, vanillic acid was the main compound (51%). The antioxidant activities of C. cyminum essential oils and acetone extracts obtained from the three organs were assessed using four tests [1,1-diphenyl-2-picrylhydrazyl (DPPH), ß-carotene/linoleic acid, reducing power, and chelating power assays]. The acetone extract of flowers was strongly effective as a DPPH radical scavenger, lipid peroxidation inhibitor, and reducing agent, with IC(50) values of 4, 32, and 8 µg/mL, respectively. Moreover, the acetone extract of stems and leaves showed the highest chelating power. However, the essential oils exhibited moderate activities in the different tests.