Metal hyperaccumulating Brassicaceae from the ultramafic area of Yahyalı in Kayseri province,Turkey

Many of the plants found in serpentine areas are endemics and they may accumulate Ni at high concentration. High accumulation of Cr is rare, or in some views, never properly demonstrated. Generally, a very small proportion of any serpentine flora shows high accumulation of Ni, in some serpentine areas Ni accumulators are completely absent. There are approximately 570 hyperaccumulator plant species found on earth, 450 of them are Ni hyperaccumulators. A few of the Ni accumulators have potential for phytoremediation or phytomining. In the present study, 19 different Brassicaceae members growing in serpentine habitats in the district of Yahyal?, Kayseri province, Turkey viz., members of genera Aethionema, Alyssum, Arabis, Heldreichia, Hesperis, Iberis, Isatis, Microthlaspi, Odontarrhena, Pseudosempervivum and Thlaspi were investigated. Nickel concentrations in the soil and underground and aboveground parts of plants were determined by using ICP-OES. It was observed that Ni concentrations of seven taxa (Odontarrhena muralis, O. oxycarpa, Isatis cappadocica subsp. cappadocica, Microthlaspi perfoliatum, Pseudosempervivum sempervivum, Thlaspi triangulare, Thlaspi rosulare) reach the threshold criterion of 1,000 mg kg^?1 for Ni hyperaccumulation. In this study Ni concentrations in aboveground tissues of I. cappadocica subsp. cappadocica are determined as 5,587 mg kg^?1 (in dry weight). Accordingly, it is suggested that this taxon be added to the list of Ni hyperaccumulator plants.     

Carotenoid Profile in <Emphasis Type="Italic">Prochlorococcus</Emphasis> sp. and Enrichment of Lutein Using Different Nitrogen Sources

Various carotenoids of the cyanobacterium Prochlorococcus sp. are identified using chromatographic/spectroscopic techniques and quantified using HPLC-DAD. In the present study, β-apo-8′-carotenal was used as internal standard. Identification of carotenoids was carried out by comparing the retention time, absorption spectra, and mass spectra of unknown peaks with reference standards. All-trans-lutein was found to be the major carotenoid in this cyanobacterium, and, therefore, algal productivity and the potential for lutein accumulation were analyzed as a function of different nitrogen sources such as nitrate, nitrite, ammonia, and urea for cultivation. Among them, urea clearly led to the best lutein accumulation. According to the experimental evidence, lutein increased from 2.54 to 3.34 mg g^?1 in the cyanobacteria when urea was used as the nitrogen source.     

Effects of supplementation with a combination of cobalt and ascorbic acid on antioxidant enzymes and lipid peroxidation levels in streptozocin-diabetic rat liver

The effect of cobalt(II) chloride (CoCl2) and CoCl2 with ascorbic acid (AA) on components of the antioxidant defense system and lipid oxidative damage were studied in controls and streptozotocin-induced diabetic rat livers. Three days after injection, rats received either 0.5 mM CoCl2 or 0.5 mM CoCl2 with a combination of 1 g/L AA in drinking water up to 6 wk. The elevated blood glucose levels in diabetic rats were about 12% restored by oral administration of CoCl2 (0.05 mM) and were significant reduced (46%) following AA addition (1 g/L) to CoCl2. Cobalt therapy effectively decreased the increased activities of catalase (CAT), superoxide dismutase (SOD), and thiobarbituric acid reactant substances (TBARS) but could not restore the increased glutathione peroxidase (GSH-Px) in the liver of diabetic rats. Our findings suggest that cobalt therapy may prove effective in improving the impaired antioxidant status during the early state of diabetes, and ascorbic acid supplementation at this dose potentiates the effectiveness of cobalt action.     

Dietary zinc modifies the characteristics of endothelial dilation in normozincemic rats

Because zinc attenuates endothelial cell dysfunction that proceeds atherosclerosis, depressed zinc status may be involved in the initiation of endothelial dysfunction. However, before recommending a zinc-enriched diet to reduce the risks for atherosclerosis, the effect of excess zinc on endothelial cell functions in normozincemic status should be known. Therefore, in this study, the effect of dietary zinc on normal endothelial cell functions in animals subjected to a diet containing 334 +/- 58 ppm zinc for 30 d was studied to see whether supplemented zinc has an effect on endothelial cells. Despite a slight increase in blood zinc, unaltered aortic and kidney zinc contents were associated with unchanged blood pressure in rats subjected to a zinc-enriched diet. Increased basal nitric oxide and prostacyclin were accompanied by a normal response to phenylephrine. Dietary zinc influenced neither endothelial-dependent nor endothelial-independent relaxations significantly. However, it elevated the share of M1-type cholinoceptor response as well as dilator prostaglandin release, which seems to be nitric oxide dependent. There was a strong correlation (r=0.826, p<0.05) between M1-type cholinoceptor response and prostacyclin release in zinc-treated rings. These results suggested that zinc ions increases M1-mediated prostacyclin release in normal endothelial cells without altering intracellular pathways.     

Screening for free radical scavenging and cell aggregation inhibitory activities by secondary metabolites from Turkish Verbascum species

Free radical scavenging and cell aggregation inhibitory activities of 36 secondary metabolites isolated from the methanolic extracts of Verbascum cilicicum Boiss., V. lasianthum Boiss. ex Bentham, V pterocalycinum var. mutense Hub.-Mor., and V. salviifolium Boiss. (Scrophulariaceae) were investigated. The isolated compounds, 6-O-vaniloyl ajugol (1), ilwensisaponin A (2), ilwensisaponin C (3), verbascoside (4), beta-hydroxyacteoside (5), martynoside (6), poliumoside (7), forsythoside B (8), angoroside A (9), dehydrodiconiferyl alcohol-9-O-beta-D-glucopyranoside (10), dehydrodiconiferyl alcohol-9'-O-beta-D-glucopyranoside (11), apigenin 7-O-beta-glucopyranoside (12), luteolin 7-O-beta-glucopyranoside (13), luteolin 3'-O-beta-glucopyranoside (14) and chrysoeriol 7-O-beta-glucopyranoside (15), exhibited a dose-dependent inhibition of bioautographic and spectrophotometric DPPH activities. Verbascoside (4) was the most active (IC50 4.0 microg/ml) comparing it to vitamin C (IC50 4.4 microg/ml) to inhibit phorbol 12-myristate 13-acetate (PMA)-induced peroxide-catalyzed oxidation of 2',7'-dichlorofluorescein (DCFH) by reactive oxygen species (ROS) within human promyelocytic HL-60 cells. Ilwensisaponin A (2) (MIC 6.9 microg/ml) showed moderate in vitro activity on lymphocyte-associated antigen-1 (LFA-1)/intercellular adhesion molecule-1 (ICAM-1)-mediated aggregation using the HL-60 cell line [positive control was cytochalasin B (MIC 2.3 microg/ml)]. None of the other compounds showed free radical scavenging and cell aggregation inhibitory activities.     

Cholinesterase inhibitory and antioxidant properties of Verbascum mucronatum Lam. and its secondary metabolites

The aqueous extract of Verbascum mucronatum Lam. along with its fractions and secondary metabolites were assessed for their antioxidant, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) inhibitory activities. The antioxidant activity was evaluated by three methods: as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferrous ion-chelating effect, and ferric-reducing antioxidant power (FRAP) tests. The AChE activity was determined by the Ellman method using an ELISA microplate reader. Phytochemical investigations revealed the presence of four iridoid glucosides, ajugol (1), aucubin (2), lasianthoside I (3) and catalpol (4), two saponins, ilwensisaponin A (5) and C (6), and a phenylethanoid glycoside, verbascoside (7), in Verbascum mucronatum. Their structures were elucidated by spectral techniques. The aqueous extract and fractions including the phenylethanoid glycoside 7 showed DPPH scavenger effect and had the best FRAP. Besides these results, one of the phenylethanoid fractions displayed the highest ferrous ion-chelating effect. While only 7 was found to possess moderate AChE inhibition, the extract, fractions, and all other tested compounds did not inhibit AChE and BChE.     

Effects of propolis,caffeic acid phenethyl ester,and pollen on renal injury in hypertensive rat: An experimental and theoretical approach

The objective of this study was to evaluate the antioxidant effects of propolis, caffeic acid phenethyl ester (CAPE; active compound in propolis), and pollen on biochemical oxidative stress biomarkers in rat kidney tissue inhibited by N^ω‐nitro‐L‐arginine methyl ester (L‐NAME). The biomarkers evaluated were paraoxonase (PON1), oxidative stress index (OSI), total antioxidant status (TAS), total oxidant status (TOS), asymmetric dimethylarginine (ADMA), and nuclear factor kappa B (NF‐κB). TAS levels and PON1 activity were significantly decreased in kidney tissue samples in the L‐NAME‐treated group (P < 0.05). The levels of TAS and PONI were higher in the L‐NAME plus propolis, CAPE, and pollen groups compared with the L‐NAME‐treated group. TOS, ADMA, and NF‐κB levels were significantly increased in the kidney tissue samples of the L‐NAME‐treated group (P < 0.05). However, these parameters were significantly lower in the L‐NAME plus propolis, CAPE, and pollen groups (P < 0.05) compared with rats administered L‐NAME alone (P < 0.05). Furthermore, the binding energy of CAPE within catalytic domain of glutathione reductase (GR) enzyme as well as its inhibitory mechanism was determined using molecular modeling approaches. In conclusion, experimental and theoretical data suggested that oxidative alterations occurring in the kidney tissue of chronic hypertensive rats may be prevented via active compound of propolis, CAPE administration.     

Different responses of fluvastatin to cholesterol‐induced oxidative modifications in rabbits: evidence for preventive effect against DNA damage

Hypercholesterolemia is a major risk factor for atherosclerosis and related occlusive vascular diseases. We investigated the effect of low‐dose fluvastatin (2 mg kg^?1 day^?1) on antioxidant enzyme activities [superoxide dismutase (SOD), catalase], vascular reactivity changes and oxidatively induced DNA damage in early stage of atherosclerosis in hypercholesterolemic rabbits. The animals were divided into three groups each composed of 10 rabbits. The control group received a regular rabbit chow diet, and the cholesterol group had hypercholesterolemic diet (2%, 4 weeks). The fluvastatin group was given hypercholesterolemic diet plus fluvastatin. Dietary intake of cholesterol significantly increased total cholesterol levels in rabbits (control, 0.85 ± 0.29; cholesterol, 12.04 ± 4.61; fluvastatin, 8.07 ± 2.72 mmol l^?1 ). Hypercholesterolemic diet revealed discernible fatty streaks in arcus aortae. Fluvastatin significantly reduced the areas of the lesions. The diet significantly increased SOD activities in both erythrocyte and tissue. Treatment with fluvastatin normalized the increased activity of SOD in both erythrocyte and aortic tissues from the cholesterol group. Cholesterol feeding decreased the sensitivity to acetylcholine, and treatment with fluvastatin significantly restored the diminished sensitivity to acetylcholine in thoracic aortae. Cholesterol feeding caused oxidatively induced DNA damage in liver tissues determined by the increased levels of 8‐hydroxyguanine (8‐OH‐Gua) and 2,6‐diamino‐4‐hydroxy‐5‐formamidopyrimidine (FapyGua). Fluvastatin decreased only FapyGua level in liver. In conclusion, our results may suggest that fluvastatin seems to play a protective role on high cholesterol‐induced oxidative stress and DNA damage. Copyright © 2012 John Wiley & Sons, Ltd.     

Inhibitory effects of indole α‐lipoic acid derivatives on nitric oxide production in LPS/IFNγ activated RAW 264.7 macrophages

Alpha‐lipoic acid (α‐lipoic acid) is a potent antioxidant compound that has been shown to possess anti‐inflammatory effects. RAW 264.7 macrophages produce various inflammatory mediators such as nitric oxide, IL‐1β, IL‐6 and TNF‐alpha upon activation with LPS ( Lipopolysaccharide) and IFNγ (interferon gamma). In this study, the effect of 12 synthetic indole α‐lipoic acid derivatives on nitric oxide production and iNOS (inducible nitric oxide synthase) protein expression in LPS/IFNγ activated RAW 264.7 macrophages was determined. Cell proliferation, nitric oxide levels and iNOS protein expression were examined with thiazolyl blue tetrazolium blue test, griess assay and western blot, respectively. Our results showed that all of the indole α‐lipoic acid derivatives showed significant inhibitory effects on nitric oxide production and iNOS protein levels (p < 0.05). The most active compounds were identified as compound I‐4b, I‐4e and II‐3b. In conclusion, these indole α‐lipoic acid derivatives may have the potential for treatment of inflammatory conditions related with high nitric oxide production. Copyright © 2015 John Wiley & Sons, Ltd.