Background: Medicinal plants (especially belong to Lamiaceae family) are potential sources of new drugs to improve the treatment of diseases whose treatment is associated to anti-oxidative agents. In this paper, the Ferric Reducing Ability of Plasma (FRAP) activity of some Lamiaceae and Apiaceae species, has been evaluated.Methods: Aerial parts of the plants were dried, cut into small pieces and extracted with ethyl acetate and methanol, respectively, by percolation at room temperature. Different concentrations of the plant extracts were investigated for antioxidant power using FRAP assay.Results: The extracts showed a considerable antioxidant effect from 16.36 mmol of FeSO4 /100 g dry plant equivalents in Scutellaria tornefortii (AcOEt extract) to 404.12 mmol of FeSO4 /100 g dried plant in Salvia macro siphon (MeOH extract).Conclusions: All the plant samples possessed antioxidant activity, while Salvia macrosiphon (MeOH extract), Pimpinella tragioides (MeOH extract) and Salvia limbata (AcOEt extract) showed significantly the highest results and Scutellaria tornefortii (AcOEt extract) showed the lowest power. Antioxidant activity of these species might be due to the presence of flavonoids, rosmarinic acid, coumarins even monoterpenes (like myrcene) in the plant extracts.

Background: Because of the difficulty in measuring each antioxidant component separately and the interactions among different antioxidant components in the serum or plasma, several methods have been developed to assess the total antioxidant capacity. The objective of the present study was to evaluate and compare the total Radical-Trapping Antioxidant Potential (TRAP) and Ferric Reducing Ability of Plasma (FRAP) methods for assessing the total antioxidant capacity of rat serum.Materials and methods: Serum samples were obtained from 10 healthy male Wistar rats (8 weeks, 190±5 g). The total TRAPs were determined based on the protection afforded by antioxidants against the decay of R-Phycoerythrin fluorescence emission during a controlled per oxidation reaction initiated by AAPH. The FRAP was determined based on the reduction of the ferric tripyridyltriazine [Fe (III)–TPTZ] complex to the ferrous tripyridyltriazine [Fe(II)–TPTZ] at low pH. The Fe (II)–TPTZ complex gives a blue color with an absorbance maximum at 593 nm. The final results were converted to m mol Trolox equivalents/L.Results: The total antioxidant capacity of rat serum, measured by TRAP or FRAP methods was stable over a 4-week time period. The value of total antioxidant capacity of rat serum determined by TRAP method was three folds higher than that of FRAP method. The main contributors to rat serum TRAP and rat serum FRAP were albumin (30.33%) and uric acid (57.13%) respectively. The amount of contribution of b -carotene in rat serum TRAP was 7.22 % and in rat serum FRAP was 0%.Conclusion: The antioxidant capacity of an antioxidant against a free radical does not necessarily equal with its ability to reduce Fe (III) to Fe (II).

Lipid and lipoprotein metabolism is affected by many factors, among them thyroid hormones. Lipid and apolipoprotein disorders are common findings in patients with thyroid dysfunction. Moreover, LDL-C oxidation is more common in these patients than the normal population. This study aims at assessing lipids, lipoproteins, apolipoproteins and serum paraoxonase activity in patients with thyroid dysfunction and comparing them with normal controls. In this study 99 patients with thyroid dysfunction (49 hypothyroid and 50 hyperthyroid) were each compared with a separately age and sex matched control group of 50. A fasting blood sample was obtained and serum total cholesterol, triglycerides, apolipoproteins A-I and B, and paraoxonase activity were measured. In hyperthyroid patients, significant reductions in serum paraoxonase activity (45±23 vs. 67±37 Iu/ml, P<0.001), triglycerides (112±53 vs. 166±130 mg/dl, P<0.05), apolipoprotein A-I (137±26 vs. 154±21 mg/dl, P<0.001) and apolipoprotein B (75±18 vs. 85±25 mg/dl, P<0.05) were found. Hypothyroid patients had lower paraoxonase activity (46±21 vs. 64±32 Iu/ml, P<0.005) than controls and higher total cholesterol (224±69 vs. 185±41 mg/dl, P<0.001), LDL-C (133±59 vs. 93±36 mg/dl, P<0.001), and apo B (107±37 vs. 84±23 mg/dl, P<0.001). The results show significant changes of lipid levels in thyroid dysfunction, like previous studies. Also, for the first time in both hypo and hyperthyroid patients we observed significant reduction in serum paraoxonase activity. According to these findings, increased LDL oxidation in thyroid dysfunction, at least to some extent, can be attributed to reduced serum paraoxonase activity.

Microalgae are one of the rich sources of natural antioxidants in various applications in the food and pharmaceutical industries. In this study, the effects of temperature stress (23˚ c, 28˚ c, 33˚ c) and pH (5, 7, 8, 9) on antioxidant activity, phenolic and flavonoids content and on the amount of colorants in the microalgae Scenedesmus sp. were studied. Environmental conditions for all treatments were12: 12 light: dark, continuous aeration, and a 16-day period. The results showed that, the best conditions for antioxidant activity and flavonoid production occurred at high pH (8 and 9) and low temperature (23˚ c). Concerning phenolic content, the results indicated that temperature (23˚ C) plays significantly an effective role than pH in increasing the phenolic content of the algae (7/53 ± 0/06 mg GAE /g DW), and pH caused a significant decrease (p<0. 05) in phenolic content compared to control. Although pH and temperature did not affect the amount of chlorophyll α , but in general, the results indicate that pH and temperature can affect the antioxidants content of the Scenedesmus sp. microalgae.