Comparative study of the antioxidant activity of the essential oils of five plants against the H2O2 induced stress in Saccharomyces cerevisiae.

The purpose of this work was to investigate the protective effect of five essential oils (EOs); Rosmarinus officinalis, Thymus vulgaris, Origanum compactum Benth., Eucalyptus globulus Labill. and Ocimum basilicum L.; against oxidative stress induced by hydrogen peroxide in Saccharomyces cerevisiae. The chemical composition of the EOs was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The in vitro antioxidant activity was evaluated and the protective effect of EOs was investigated. Yeast cells were pretreated with different concentrations of EOs (6.25-25 µg/ml) for an hour then incubated with H2O2 (2 mM) for an additional hour. Cell viability, antioxidants (Catalase, Superoxide dismutase and Glutathione reductase) and metabolic (Succinate dehydrogenase) enzymes, as well as the level of lipid peroxidation (LPO) and protein carbonyl content (PCO) were evaluated. The chemical composition of EOs has shown the difference qualitatively and quantitatively. Indeed, O. compactum mainly contained Carvacrol, O. basilicum was mainly composed of Linalool, T. vulgaris was rich in thymol, R. officinalis had high α-Pinene amount and for E. globulus, eucalyptol was the major compound. The EOs of basil, oregano and thyme were found to possess the highest amount of total phenolic compounds. Moreover, they have shown the best protective effect on yeast cells against oxidative stress induced by H2O2. In addition, in a dose dependent manner of EOs in yeast medium, treated cells had lower levels of LPO, lower antioxidant and metabolic enzymes activity than cells exposed to H2O2 only. The cell viability was also improved. It seems that the studied EOs are efficient natural antioxidants, which can be exploited to protect against damages and serious diseases related to oxidative stress.

Physicochemical Evaluation of Edible Cyanobacterium Arthrospira platensis Collected from the South Atlantic Coast of Morocco: A Promising Source of Dietary Supplements.

The cyanobacterium Arthrospira platensis (A. platensis)-a genus of nonheterocystous filamentous cyanobacteria-is used in industrial applications and as a food supply. The current research work aims to study the physicochemical characteristics of A. platensis indigenous to the Moroccan Atlantic coast at Laayoune (Foum El Oued lagoon). The contents of proteins, carbohydrates, vitamins, lipids, minerals, heavy metals, energy value, humidity, ash, pigments, and tannins in A. platensis were investigated using protocols as described in the earlier literature. The values of protein, carbohydrate, and lipid contents in A. platensis were 58.9 ± 0.07, 14.67, and 45.54% respectively. The values of vitamins B2 and B3 dosed in A. platensis were 1.31 ± 0.19 and 30.8 ± 0.001 mg/kg, respectively. The values of heavy metals including lead and chromium were 70 ± 4.5 and 5 ± 0.5 PPB (parts-per-billion), respectively; however, no trace concerning cadmium was detected. The values of energy value, humidity, and ash content were 346.48 ± 0.21, 11.6 ± 0.17%, and 9.1 ± 0.21% kcal/100 g, respectively. The results of pigment content showed the presence of chlorophyll b, chlorophyll a, and carotenoids of 37.506 ± 3.38, 26.066 ± 3.08, and 9.52 ± 0.22 mg/g, respectively. The results obtained revealed that A. platensis indigenous to the Moroccan Atlantic coast at Laayoune was found to be very rich in proteins, carbohydrates, vitamins, minerals, ash, and pigments and lower in heavy metals and saturated fats when compared with species investigated in the literature. Thus, A. platensis indigenous to the Moroccan Atlantic coast at Laayoune fulfills the requirements for being used as dietary supplements.

Evaluation of Moroccan microalgae: Spirulina platensis as a potential source of natural antioxidants.

Background Ethanolic, aqueous and lipidic extracts of Spirulina platensis were evaluated for their bioactive substances (polyphenols and fatty acids) and antioxidant activities using two different assays diphenyl-1-picrylhydrazyl (DPPH) and azino-bis (ethylbenzthiazoline-6- sulfonicacid (ABTS)). Methods The phenolic compounds amounts were determined by colorimetric assays and were analyzed by high-performance and liquid chromatography (HPLC) method. The identification of phenolic compounds in the extract was accomplished by comparison of their retention times with those of pure standards. The chemical composition of fatty acids in lipidic extract was determined by GC/FIDs and GC/MS method. Results The obtained results revealed that using DPPH, the ethanolic extract recorded the highest activity with (IC50=449 µg/mL ± 83). It was characterized with a high levels of phenolic and flavonoid content 0.33 ± 0.01 mg GAE/g dw and 0.21 ± 0.01 mg quercetin/g dw, respectively. The ethanolic extract showed the presence of caffeic acid, syringic acid, ferulic acid, p-coumaric acid, chlorogenic acid, kaempferol, quercetin and apigenin. Those entire phenolic compounds seem participle synergistically to the pronounced higher activity. To the best of our knowledge, the apigenin (4', 5, 7,-trihydroxyflavone), a natural compound which is famously known by its potent antiradical activity, was identified for the first time in Moroccan S. platensis only in the ethanolic extract. A high positive correlation (r=0.895) between the antioxidant activity and the chemical composition of ethanolic extract was observed. For ABTS, lipidic extract showed the highest activity with (IC50=740 µg/mL ± 12). A total of 15 fatty acids compounds, amounting 89.73% of the extract were identified. γ-linolenic acid (GLA) (39.02%) and α-linolenic acid (ALA) (13.85%) were the major component and contribute greatly to the antioxidant activity observed. The lipidic extract has a high content of unsaturated fatty acids (70.95%) which are often exhibited very high antioxidant activity since they have two or more double bonds and chain lengths. The aqueous extract either with DPPH or ABTS methods, recorded low antioxidant activity. Its correlation was r=0.499, lower than found in the ethanolic extract. Conclusions These results showed that Spirulina platensis could be considered as a valuable source of fatty acids and phenolics with potent antioxidant activity. It may be employed in the manufacture of pharmaceutical drugs as an alternative source of natural antioxidants.

Antioxidant-rich food intakes and their association with blood total antioxidant status and vitamin C and E levels in community-dwelling seniors from the Quebec longitudinal study NuAge.

A cross-sectional study was designed to investigate the association between current consumption of a series of 26 common antioxidant-rich foods (ARF) with serum total antioxidant status (TAS) and plasma vitamin C and E levels in community-dwelling older adults. A convenience sample of the first 94 non-smoking Caucasian men (54%) and women (46%) enrolled in the Quebec Longitudinal Study NuAge were selected. The "Functional Foods Consumption Frequency Questionnaire" (FFCFQ) was administered at recruitment (T1) to ascertain patterns of consumption of ARF over the lifetime. The total Oxygen Radical Antioxidant Capacity (ORAC) of 25 ARF reported by subjects was estimated using published values. Serum TAS was determined based on the Trolox equivalent antioxidant capacity (TEAC) assay while plasma vitamins C and E (α- and γ-tocopherol) levels were analyzed by HPLC. The numbers of ARF eaten daily at T1, estimated from the FFCFQ and calculated from the diet recalls, were significantly correlated (r=0.51, P<0.0001) and each measure was associated with total ORAC content (r=0.34, P<0.001 and r=0.59, P<0.0001 for FFCFQ and recalls, respectively). No significant association was found between TAS and the total ORAC value of ARF determined from the quantitative 24-h diet recalls. However, daily ARF consumption at T1 obtained from the FFCFQ was significantly and positively correlated with TAS (r=0.26, P<0.05) and circulating levels of vitamin C (r=0.25, P<0.02) and α-tocopherol (r=0.22, p<0.05) and negatively correlated with plasma γ-tocopherol (r=-0.25, P<0.025). These results highlight associations between ARF consumption and circulating levels of antioxidants in the elderly and suggest benefits from antioxidant-rich foods during aging.

Antiatherogenic activity of extracts of Argania spinosa L. pericarp: beneficial effects on lipid peroxidation and cholesterol homeostasis.

Prevention of lipoprotein oxidation by natural compounds may prevent atherosclerosis via reducing early atherogenesis. In this study, we investigated for the first time the beneficial properties of methanolic extract of argania pericarp (MEAP) towards atherogenesis by protecting human low-density lipoprotein (LDL) against oxidation while promoting high-density lipoprotein (HDL)-mediated cholesterol efflux. By measuring the formation of malondialdehyde (MDA) and conjugated diene as well as the lag phase and the progression rate of lipid peroxidation, the MEAP was found to possess an inhibitory effect. In addition, MEAP reduced the rate of disappearance of alpha-tocopherol as well as the apoB electrophoretic mobility in a dose-dependent manner. These effects are related to the free radical scavenging and copper-chelating effects of MEAP. In terms of cell viability, MEAP has shown a cytotoxic effect (0-40 microg/mL). Incubation of 3H-cholesterol-loaded J774 macrophages with HDL in the presence of increasing concentrations of MEAP enhanced HDL-mediated cholesterol efflux independently of ABCA1 receptor pathways. Our findings suggest that argania seed pericarp provides a source of natural antioxidants that inhibit LDL oxidation and enhance cholesterol efflux and thus can prevent development of cardiovascular diseases.

Effect of PON1 polymorphism on HDL antioxidant potential is blunted with aging.

Paraoxonase1 is a HDL-associated enzyme, which is responsible for their antioxidant property. This study was aimed to investigate the effect of PON1 [Q192R] and [L55M] genotypes on susceptibility of LDL and HDL to lipid peroxidation and on antioxidant activity of HDL as a function of aging. Seventy-eight healthy subjects distributed in two age groups, young (20-30 years) and elderly (60-89 years) were recruited. PON1 activities and genotype polymorphisms were determined for each subject. LDL and HDL susceptibility to lipid peroxidation was evaluated by the measure of lag-phase (LP) for conjugated diene formation. HDL antioxidant property was evaluated by the measure of their capacity to protect LDL against lipid peroxidation. Our results show that LP for LDL and HDL peroxidation decreased with age of donors. Moreover, PON1 genotypes affect significantly the susceptibility of LDL and HDL to lipid peroxidation. Furthermore, basal- and salt-stimulated paraoxonase as well arylesterase activities were significantly reduced in elderly compared to young subjects. These results show a beneficial effect of PON1 towards susceptibility of HDL to oxidation as well to their antioxidant effect. However, this PON1 protective effect seems to be blunted with advancing age. Altogether our results suggest that the decrease in the PON1 protective effect with aging may contribute to the acceleration of the atherosclerosis process in elderly.

Marrubium vulgare extract inhibits human-LDL oxidation and enhances HDL-mediated cholesterol efflux in THP-1 macrophage.

The objective of the present study was to elucidate the beneficial properties of aqueous extracts of Marrubium vulgare (AEM) towards cardiovascular disease by protecting human-LDL against lipid peroxidation and promoting HDL-mediated cholesterol efflux. Human-LDL were oxidised by incubation with CuSO(4) in the presence of increased concentrations of AEM (0-100 microg/ml). LDL lipid peroxidation was evaluated by conjugated diene formation, vitamin E disappearance as well as LDL-electrophoretic mobility. HDL-mediated cholesterol efflux assay was carried out in human THP-1 macrophages. Incubation of LDL with AEM significantly prolonged the lag phase (P=0.014), lowered the progression rate of lipid peroxidation (P=0.004), reduced the disappearance of vitamin E and the electrophoretic mobility in a dose-dependent manner. Also, incubation of HDL with AEM significantly increased HDL-mediated cholesterol efflux from THP-1 macrophages implicating an independent ATP binding cassette A1 (ABCA1) pathways. Our findings suggest that M. vulgare provides a source of natural antioxidants, which inhibit LDL oxidation and enhance reverse cholesterol transport and thus can prevent cardiovascular diseases development. These antioxidant properties increase the anti-atherogenic potential of HDL.

Argan oil: which benefits on cardiovascular diseases?

AIM: The argan oil, extracted from argan-tree fruits, has been known for its various pharmacological properties and used as a natural remedy since several centuries. In this review, we present a summary of the results obtained from a survey of the literature on argan oil. DATA SYNTHESIS: Various studies conducted in vitro or on human and animal models suggest that argan oil could play a beneficial role in cardiovascular diseases prevention and its consumption could protect against atherosclerosis and cancer via a variety of biological mechanisms. CONCLUSION: Argan oil reduces cardiovascular risk and may be used as anti-atherogenic oil.

Consumption of argan oil may have an antiatherogenic effect by improving paraoxonase activities and antioxidant status: Intervention study in healthy men.

BACKGROUND AND AIM: Due to its high antioxidant and mono- and polyunsaturated fatty acid content virgin argan oil (VAO) could play a beneficial role in cardiovascular prevention. We were therefore interested in determining whether the consumption of VAO could improve plasma paraoxonase (PON1) activities and antioxidant status in healthy men. METHODS AND RESULTS: Sixty young men were included in this interventional study. They were given a controlled diet for 2 weeks as baseline and then received 25 g/day of butter. The group was randomised to two diet group periods of 3 weeks each. The VAO group received 25 ml/day of oil and the extra virgin olive oil (EVO) group received the same quantity of EVO as control group. Plasma PON1 activities, antioxidant vitamins and LDL susceptibility to oxidation were measured. The analysis of the results shows that PON1 activities increase significantly in both groups and that lipoperoxides and conjugated dienes formation decreases significantly in VAO and EVO groups compared to baseline values (P=0.001 and P=0.014, respectively). Vitamin E concentration increases significantly only in VAO group (P=0.007). Susceptibility of LDL to lipid peroxidation shows a significant increase in lag phase and a significant decrease in maximum diene production in VAO (P=0.005) and EVO groups (P=0.041 and P=0.005, respectively). CONCLUSIONS: Our findings confirm the beneficial effect of EVO on plasma antioxidant status and show for the first time the same effect for VAO supplementation in man. Thus, VAO offers an additional natural food supplement to reduce cardiovascular risk.

Evidence of hypolipemiant and antioxidant properties of argan oil derived from the argan tree (Argania spinosa).

BACKGROUND: Virgin argan oil is of interest in cardiovascular risk prevention due to its fat composition and antioxidant compounds. AIMS: We investigated with Moroccan subjects the effect of regular virgin argan oil consumption on lipid profile and antioxidant status and the in vitro effect of argan oil minor compounds (tocopherols, sterols and polyphenols) on LDL peroxidation. DESIGN: Healthy subjects (20 men, 76 women) were studied. Sixty-two were regular consumers of argan oil and 34 were non-consumers. METHODS: Fasting plasma lipids, antioxidant vitamins and LDL oxidation susceptibility were analyzed. In vitro LDL oxidation by phenolic and apolar compounds of virgin argan oil were performed. RESULTS: Diet composition of argan oil consumers has a higher significant content of polyunsaturated fatty acids than that of non-consumers (8.8 +/- 1.0 vs. 6.6 +/- 0.9 g, P < 0.05). Subjects consuming argan oil have lower levels of plasma LDL cholesterol (12.7%, P < 0.05) and Lp(a) (25.3%, P < 0.05) compared with the non-consumers. In argan oil consumers, plasma lipoperoxides were lower (58.3%, P < 0.01) and molar ratio alpha-tocopherol/total cholesterol (21.6%, P < 0.05) and alpha-tocopherol concentration (13.4%, P < 0.05) were higher compared with the non-consumers group. In spite of higher levels of plasma antioxidant and lower levels of lipoperoxides in argan oil consumers, LDL oxidation susceptibility remained fairly similar. A strong positive correlation was observed between increasing phenolic extract, sterol and tocopherol concentrations and the LDL-Lag phase (P < 0.05). CONCLUSIONS: Our findings suggest for the first time that regular consumption of virgin argan oil induces a lowering of LDL cholesterol and has antioxidant properties. This oil offers an additional natural food to reducing cardiovascular risk.