Hypocholesterolemic effects of phenolic extracts and purified hydroxytyrosol recovered from olive mill wastewater in rats fed a cholesterol-rich diet     

Fki I  Sahnoun Z  Sayadi S 《Journal of agricultural and food chemistry》2007,55(3):624-631

In our previous studies, a phenolic-rich extract of olive mill wastewaters (OMW) was prepared under optimal conditions, using a continuous countercurrent extraction unit, and hydroxytyrosol was purified from the obtained OMW extract. The antioxidant activity of OMW extract and hydroxytyrosol was determined by a series of models in vitro. In this study, the hypocholesterolemic effects of hydroxytyrosol and OMW extract in rats fed a cholesterol-rich diet were tested. Wistar rats, fed a standard laboratory diet or a cholesterol-rich diet for 16 weeks, were used. Serum lipid levels, as well as thiobarbituric acid reactive substances (TBARS) and superoxide dismutase and catalase activities in liver were examined. Cholesterol-rich diet-induced hypercholesterolemia was manifested in the elevation of serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C). Administration of a low-dose (2.5 mg/kg of body weight) of hydroxytyrosol and a high-dose (10 mg/kg of body weight) of OMW extract significantly lowered the serum levels of TC and LDL-C while increasing the serum levels of high-density lipoprotein cholesterol (HDL-C). Furthermore, the TBARS contents in liver, heart, kidney, and aorta decreased significantly after oral administration of hydroxytyrosol and OMW extract as compared with those of rats fed a cholesterol-rich diet. In addition, OMW phenolics increased CAT and SOD activities in liver. These results suggested that the hypocholesterolemic effect of hydroxytyrosol and OMW extract might be due to their abilities to lower serum TC and LDL-C levels as well as slowing the lipid peroxidation process and enhancing antioxidant enzyme activity.  相似文献   

The tides of Titan     

Iess L  Jacobson RA  Ducci M  Stevenson DJ  Lunine JI  Armstrong JW  Asmar SW  Racioppa P  Rappaport NJ  Tortora P 《Science (New York, N.Y.)》2012,337(6093):457-459

We have detected in Cassini spacecraft data the signature of the periodic tidal stresses within Titan, driven by the eccentricity (e = 0.028) of its 16-day orbit around Saturn. Precise measurements of the acceleration of Cassini during six close flybys between 2006 and 2011 have revealed that Titan responds to the variable tidal field exerted by Saturn with periodic changes of its quadrupole gravity, at about 4% of the static value. Two independent determinations of the corresponding degree-2 Love number yield k(2) = 0.589 ± 0.150 and k(2) = 0.637 ± 0.224 (2σ). Such a large response to the tidal field requires that Titan's interior be deformable over time scales of the orbital period, in a way that is consistent with a global ocean at depth.  相似文献   

Twenty years of intensive fertilization and competing vegetation suppression in loblolly pine plantations: Impacts on soil C, N, and microbial biomass     

Sami W. Rifai  Bruce Borders 《Soil biology & biochemistry》2010,42(5):713-347

Silvicultural treatments of fertilization (F) and competing vegetation suppression (H) have continued to increase as demands for forest products have grown. The effects of intensive annual F and H treatments on soil C, N, microbial biomass, and CO₂ efflux were examined in a two-way factorial experiment (control, F, H, FxH) in late-rotation (20+ years) loblolly pine stands. This study is unique in testing the cumulative effects of continual H and repeated F treatments for the first 20 years of stand growth, an uncommon operational practice, and in having treatments replicated upon four different soil types in the state of Georgia, USA. Annual fertilization included applications of N, P, K and periodic additions of micronutrients while competing vegetation suppression was maintained for all non-pine vegetation with herbicides throughout the rotation. Measurements included total O-horizon (forest floor) organic matter, C, and N, and 0-10 cm mineral soil pH, C, N, microbial biomass C and N, and surface CO₂ efflux. Sample collections and analyses were conducted seasonally for 1.5 yrs. Competing vegetation suppression was associated with a decrease of total soil C, soil microbial biomass C and N, and soil surface CO₂ efflux, while increasing O-horizon C:N. The fertilization treatment greatly reduced soil microbial biomass C and N, soil pH, and O-horizon C:N, while increasing O-horizon mass, N content, and soil carbon. No significant interactions between F and H were found. The combination of F and H treatments acted additively to achieve the greatest loss of soil microbial biomass, which may possibly have negative implications for long-term soil fertility.  相似文献   

Identification and antioxidant potential of flavonoids and low molecular weight phenols in olive cultivar chemlali growing in Tunisia     

Bouaziz M  Grayer RJ  Simmonds MS  Damak M  Sayadi S 《Journal of agricultural and food chemistry》2005,53(2):236-241

Increasing interest in phenolic compounds in olives is due to their antioxidant and health-enhancing properties. In this study the phenolics in fruits of the Tunisian olive cultivar Chemlali were extracted by methanol-water and fractionated using Sephadex LH-20 column chromatography. The identification of phenolic monomers and flavonoids was based on separation by high-performance liquid chromatography equipped with a diode array detector followed by liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry analysis. Oleuropein, a secoiridoid glycoside esterified with a phenolic acid, was the major compound. Eight phenolic monomers and 12 flavonoids were also identified in Chemlali olives. Five flavonoids were isolated and purified using Sephadex LH-20 column chromatography and preparative paper chromatography. The antioxidant activity of the extract and the purified compounds was evaluated by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl and by using the beta-carotene-linoleate model assay. Acid hydrolysis of the extract enhanced its antioxidant activity. Hydroxytyrosol and quercetin showed antioxidant activities similar to that of 2,6-di-tert-butyl-4-methylphenol. A hydroxyl group at the ortho position at 3' on the B ring of the flavonoid nucleus could contribute to the antioxidant activity of the flavonoids.  相似文献   

Detection of sweet and umami taste in the absence of taste receptor T1r3     

Damak S  Rong M  Yasumatsu K  Kokrashvili Z  Varadarajan V  Zou S  Jiang P  Ninomiya Y  Margolskee RF 《Science (New York, N.Y.)》2003,301(5634):850-853

The tastes of sugars (sweet) and glutamate (umami) are thought to be detected by T1r receptors expressed in taste cells. Molecular genetics and heterologous expression implicate T1r2 plus T1r3 as a sweet-responsive receptor,and T1r1 plus T1r3,as well as a truncated form of the type 4 metabotropic glutamate receptor (taste-mGluR4),as umami-responsive receptors. Here,we show that mice lacking T1r3 showed no preference for artificial sweeteners and had diminished but not abolished behavioral and nerve responses to sugars and umami compounds. These results indicate that T1r3-independent sweet- and umami-responsive receptors and/or pathways exist in taste cells.  相似文献   

Density of Mars' south polar layered deposits     

Zuber MT  Phillips RJ  Andrews-Hanna JC  Asmar SW  Konopliv AS  Lemoine FG  Plaut JJ  Smith DE  Smrekar SE 《Science (New York, N.Y.)》2007,317(5845):1718-1719

Both poles of Mars are hidden beneath caps of layered ice. We calculated the density of the south polar layered deposits by combining the gravity field obtained from initial results of radio tracking of the Mars Reconnaissance Orbiter with existing surface topography from the Mars Orbiter Laser Altimeter on the Mars Global Surveyor spacecraft and basal topography from the Mars Advanced Radar for Subsurface and Ionospheric Sounding on the Mars Express spacecraft. The results indicate a best-fit density of 1220 kilograms per cubic meter, which is consistent with water ice that has approximately 15% admixed dust. The results demonstrate that the deposits are probably composed of relatively clean water ice and also refine the martian surface-water inventory.  相似文献   

Vegetative,Chemical Status and Productivity of Zucchini Squash (<Emphasis Type="Italic">Cucurbita pepo</Emphasis> L.) Plants in Responses to Foliar Application of Pentakeep and Strigolactones Under NPK Rates     

Robert Pokluda  Sami M. Shehata  Tomas Kopta 《Gesunde Pflanzen》2018,70(1):21-29

In order to determine the effect of two bio-stimulants under NPK fertilizer rates on growth and nutrient content and yield of zucchini (squash), an experiment was conducted at Mendel university during 2014. The treatments included four NPK rates namely, 0, 75, 100 and 150% of recommended rate in combination with foliar application of Pentakeep super and strigolactones (alone and in combination) were used. This study was arranged in a split plot design in three replications. The results showed NPK at 150% led to the maximum significant increase of growth characters i.?e., leaf number, fresh and dry weight of leaves relative to unfertilized control. Chlorophyll reading increased significantly with increase in NPK supply up to NPK75%. The highest contents of N, K and nitrate were found in zucchini leaves treated with NPK at 150% of recommended rate. Yield and its component increased significantly with increase in NPK supply up to 100% of recommended rate. The combined application of Pentakeep super and strigolactones significantly maximized growth characters and fruit yield as compared to control treatment. The highest content of N generated in plants sprayed with Pentakeep super while application of Pentakeep and strigolactones did not affect the P and K contents. Whereas, control plants effectively significantly increased the chlorophyll and nitrate content of leaves.  相似文献   

Efficacy of a hydroxytyrosol-rich preparation from olive mill wastewater for control of olive psyllid, Euphyllura olivina, infestations     

Ali Debo  Thabèt Yangui  Abdelhafidh Dhouib  Moheiddine Ksantini  Sami Sayadi 《Crop Protection》2011,30(12):1529-1534

Olive mill wastewater (OMW) is a problematic by-product in Mediterranean countries. Despite this, it is a raw material that is an unfailing source of bioactive molecules. A hydroxytyrosol-rich preparation (HRP) (49.6% weight:dry weight) was extracted from fresh OMW using a hydrolysis and post-hydrolysis purification process. The field efficacy of HRP as a spray treatment (2500 l ha⁻¹) against olive psyllid, Euphyllura olivina (Hemiptera: Psyllidae), was evaluated in 2008 and 2009 in a drip-irrigated olive orchard.The HRP showed strong insecticidal activity against E. olivina at a concentration of 2 g l⁻¹ hydroxytyrosol. Application of HRP resulted in 41.1 and 72.1% control of nymphs and adults, respectively. However, HRP application did not reduce egg hatch. Neither phytotoxicity nor toxicity to auxiliary-fauna was recorded with concentrations of 1.25 g l⁻¹ or 2 g l⁻¹ HRP. But, the 2.5 g l⁻¹ concentration was slightly phytotoxic, especially at the E and F floral phenological stages of the grapes. HRP offers a natural and effective extract for control of olive psyllid and opens a new opportunity for the reuse of OMW.  相似文献   

Improving Water Use Efficiency in Semi-Arid Regions through Integrated Aquaculture/Agriculture     

Sami Abdul-Rahman  Mohammed K. Owaied  Hanafy Holail  Nadim Farajalla  Mustafa Haidar 《Journal Of Applied Aquaculture》2013,25(3):212-230

Two experiments were performed in the Bekaa plain in Lebanon to evaluate the feasibility of integrating aquaculture with established agriculture production in order to increase water productivity. Both experiments consisted of four plant management treatments: 1) Aquaculture effluent irrigation and no fertilizer; 2) aquaculture effluent irrigation and inorganic fertilizer; 3) well water irrigation and no fertilization; and 4) well water irrigation with inorganic fertilizer. In the first experiment, tilapia growth and radish production using aquaculture effluent were evaluated. All fish survived and grew, and radish production was improved by irrigating with aquaculture effluent. In the second experiment, maize (Zea mays) in large plots was irrigated with aquaculture effluent. Irrigation with effluent water improved maize production and improved soil nitrogen availability. In both experiments, fish production improved water value index and water use efficiency. Results suggest that aquaculture effluent can supplant inorganic fertilizers and could actually yield better crop production.  相似文献   

Erratum to: Effect of Bio-stimulants on Yield and Quality of Head Lettuce Grown Under Two Sources of Nitrogen     

Sami M. Shehata  U. Schmidhalter  Magdaléna Valšíková  H. Junge 《Gesunde Pflanzen》2016,68(1):59-59

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