Iodine and Halocarbon Response of Laminaria digitata to Oxidative Stress and Links to Atmospheric New Particle Production

2005 ◽  
Vol 2 (4) ◽  
pp. 282 ◽  
Author(s):  
Carl J. Palmer ◽  
Thorsten L. Anders ◽  
Lucy J. Carpenter ◽  
Frithjof C. Küpper ◽  
Gordon B. McFiggans
Keyword(s):  
Oxidative Stress ◽  
Particle Production ◽  
Marine Boundary Layer ◽  
Oxidative Capacity ◽  
Molecular Iodine ◽  
Laminaria Digitata ◽  
Organic Iodine ◽  
Free Air ◽  
Iodine Compounds ◽  
Iodine Release

Environmental Context.Various organic iodine compounds (including CH3I, CH2ClI, CH2BrI, CH2I2) are present throughout the marine boundary layer as a result of their production from seaweeds, phytoplankton, and photolysis reactions occurring in seawater. In air, these compounds rapidly photolyse to give atomic I which subsequently reacts with ozone to form iodine oxide, potentially leading to perturbations of the tropospheric oxidative capacity and nucleation of atmospheric particles. Recent research has identified molecular iodine as an additional source of iodine atoms to coastal areas. Here we study the relative roles and controls of gaseous organic and molecular iodine release from the seaweed Laminaria digitata. Abstract.Changes in the halocarbon, I2 and particle production of the brown algal kelp Laminaria digitata as a response to different chemical stresses have been investigated. Oxidative stress (caused by either exogenous hydrogen peroxide, gaseous ozone or a solution of oligoguluronates, known elicitors of oxidative stress) caused increased halocarbon and I2 production by the seaweed. The maximum I2 release was observed under exposure to O3 (at several hundred parts per billion by volume (ppbv)), whereas oligoguluronates elicited the highest release of iodine-containing halocarbons including CH2I2. Significantly greater production of I2, compared to CH2I2, was observed at atmospheric levels of ozone. Particle production was observed only when the Laminaria samples were exposed to ozone (up to 16 000 cm−3 s−1 per gram fresh weight (FW) of seaweed with a ~2 min residence time and with a total I atom flux of 1.6 × 108 cm−3 s−1 g−1 FW from photolysis of I2); passing O3-free air over the unstressed seaweed followed by secondary mixing with ozone did not result in any measurable particle formation. Our limited data indicate that ozone elicits abiotic production of I2 from Laminaria and that there is a direct relationship between the amount of I2 released and the number of particles formed. The results support the recent hypothesis that molecular iodine rather than volatile organic iodine (e.g. CH2I2) release from exposed seaweeds is the major source of coastal new particle production.

scholarly journals Direct evidence for coastal iodine particles from Laminaria macroalgae – linkage to emissions of molecular iodine

2004 ◽  
Vol 4 (3) ◽  
pp. 701-713 ◽  
Author(s):  
G. McFiggans ◽  
H. Coe ◽  
R. Burgess ◽  
J. Allan ◽  
M. Cubison ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Radiative Forcing ◽  
Particle Production ◽  
Marine Boundary Layer ◽  
Cloud Condensation Nuclei ◽  
Ultrafine Particle ◽  
Molecular Iodine ◽  
Photo Oxidation ◽  
Coastal Boundary Layer ◽  
Coastal Boundary

Abstract. Renewal of ultrafine aerosols in the marine boundary layer may lead to repopulation of the marine distribution and ultimately determine the concentration of cloud condensation nuclei (CCN). Thus the formation of nanometre-scale particles can lead to enhanced scattering of incoming radiation and a net cooling of the atmosphere. The recent demonstration of the chamber formation of new particles from the photolytic production of condensable iodine-containing compounds from diiodomethane (CH2I2), (O'Dowd et al., 2002; Kolb, 2002; Jimenez et al., 2003a; Burkholder and Ravishankara, 2003), provides an additional mechanism to the gas-to-particle conversion of sulphuric acid formed in the photo-oxidation of dimethylsulphide for marine aerosol repopulation. CH2I2 is emitted from seaweeds (Carpenter et al., 1999, 2000) and has been suggested as an initiator of particle formation. We demonstrate here for the first time that ultrafine iodine-containing particles are produced by intertidal macroalgae exposed to ambient levels of ozone. The particle composition is very similar both to those formed in the chamber photo-oxidation of diiodomethane and in the oxidation of molecular iodine by ozone. The particles formed in all three systems are similarly aspherical. When small, those formed in the molecular iodine system swell only moderately when exposed to increased humidity environments, and swell progressively less with increasing size; this behaviour occurs whether they are formed in dry or humid environments, in contrast to those in the CH2I2 system. Direct coastal boundary layer observations of molecular iodine, ultrafine particle production and iodocarbons are reported. Using a newly measured molecular iodine photolysis rate, it is shown that, if atomic iodine is involved in the observed particle bursts, it is of the order of at least 1000 times more likely to result from molecular iodine photolysis than diiodomethane photolysis. A hypothesis for molecular iodine release from intertidal macroalgae is presented and the potential importance of macroalgal iodine particles in their contribution to CCN and global radiative forcing are discussed.

scholarly journals Direct evidence for coastal iodine particles from <i>Laminaria</i> macroalgae – linkage to emissions of molecular iodine

2004 ◽  
Vol 4 (1) ◽  
pp. 939-967 ◽  
Author(s):  
G. McFiggans ◽  
H. Coe ◽  
R. Burgess ◽  
J. Allan ◽  
M. Cubison ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Radiative Forcing ◽  
Particle Production ◽  
Marine Boundary Layer ◽  
Cloud Condensation Nuclei ◽  
Ultrafine Particle ◽  
Molecular Iodine ◽  
Photo Oxidation ◽  
Coastal Boundary Layer ◽  
Coastal Boundary

Abstract. Renewal of ultrafine aerosols in the marine boundary layer may lead to repopulation of the marine distribution and ultimately determine the concentration of cloud condensation nuclei (CCN). Thus the formation of nanometre-scale particles can lead to enhanced scattering of incoming radiation and a net cooling of the atmosphere. The recent demonstration of the chamber formation of new particles from the photolytic production of condensable iodine-containing compounds from diiodomethane (CH2I2), (O'Dowd et al., 2002; Kolb, 2002; Jimenez et al., 2003a; Burkholder and Ravishankara, 2003), provides an additional mechanism to the gas-to-particle conversion of sulphuric acid formed in the photo-oxidation of dimethylsulphide for marine aerosol repopulation. CH2I2 is emitted from seaweeds (Carpenter et al., 1999, 2000) and has been suggested as an initiator of particle formation. We demonstrate here for the first time that ultrafine iodine-containing particles are produced by intertidal macroalgae exposed to ambient levels of ozone. The particle composition is very similar both to those formed in the chamber photo-oxidation of diiodomethane and in the oxidation of molecular iodine by ozone. The particles formed in all three systems are similarly aspherical and behave alike when exposed to increased humidity environments. Direct coastal boundary layer observations of molecular iodine, ultrafine particle production and iodocarbons are reported. Using a newly measured molecular iodine photolysis rate, it is shown that, if atomic iodine is involved in the observed particle bursts, it is of the order of at least 1000 times more likely to result from molecular iodine photolysis than diiodomethane photolysis. A hypothesis for molecular iodine release from intertidal macroalgae is presented and the potential importance of macroalgal iodine particles in their contribution to CCN and global radiative forcing are discussed.

scholarly journals Effects of Pyrroloquinoline Quinone on Lipid Metabolism and Anti-Oxidative Capacity in a High-Fat-Diet Metabolic Dysfunction-Associated Fatty Liver Disease Chick Model

2021 ◽  
Vol 22 (3) ◽  
pp. 1458
Author(s):  
Kai Qiu ◽  
Qin Zhao ◽  
Jing Wang ◽  
Guang-Hai Qi ◽  
Shu-Geng Wu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Lipid Metabolism ◽  
Liver Disease ◽  
Fatty Liver ◽  
Mitochondrial Biogenesis ◽  
Fatty Liver Disease ◽  
Laying Hens ◽  
Oxidative Capacity ◽  
Pyrroloquinoline Quinone ◽  
Metabolic Dysfunction

Metabolic dysfunction-associated fatty liver disease (MAFLD) and its interaction with many metabolic pathways raises global public health concerns. This study aimed to determine the therapeutic effects of Pyrroloquinoline quinone (PQQ, provided by PQQ.Na2) on MAFLD in a chick model and primary chicken hepatocytes with a focus on lipid metabolism, anti-oxidative capacity, and mitochondrial biogenesis. The MAFLD chick model was established on laying hens by feeding them a high-energy low-protein (HELP) diet. Primary hepatocytes isolated from the liver of laying hens were induced for steatosis by free fatty acids (FFA) and for oxidative stress by hydrogen peroxide (H2O2). In the MAFLD chick model, the dietary supplementation of PQQ conspicuously ameliorated the negative effects of the HELP diet on liver biological functions, suppressed the progression of MAFLD mainly through enhanced lipid metabolism and protection of liver from oxidative injury. In the steatosis and oxidative stress cell models, PQQ functions in the improvement of the lipid metabolism and hepatocytes tolerance to fatty degradation and oxidative damage by enhancing mitochondrial biogenesis and then increasing the anti-oxidative activity and anti-apoptosis capacity. At both the cellular and individual levels, PQQ was demonstrated to exert protective effects of hepatocyte and liver from fat accumulation through the improvement of mitochondrial biogenesis and maintenance of redox homeostasis. The key findings of the present study provide an in-depth knowledge on the ameliorative effects of PQQ on the progression of fatty liver and its mechanism of action, thus providing a theoretical basis for the application of PQQ, as an effective nutrient, into the prevention of MAFLD.

The synthesis of organic iodine compounds in wheat roots

1959 ◽  
Vol 46 (20) ◽  
pp. 584-584 ◽  
Author(s):  
Z. Böszörményi ◽  
Edith Cseh ◽  
L. Gáspár
Keyword(s):  
Wheat Roots ◽  
Organic Iodine ◽  
Iodine Compounds

scholarly journals Clinical efficacy of oxidative stress correction by actovegin in diabetic polyneuropathy at type 2 diabetic patients with arterial hypertension

2010 ◽  
Vol 13 (2) ◽  
pp. 84-89
Author(s):  
Ivan Petrovich Gorshkov ◽  
Vladimir Ivanovich Zoloedov ◽  
Anna Petrovna Volynkina
Keyword(s):  
Oxidative Stress ◽  
Arterial Hypertension ◽  
Diabetic Polyneuropathy ◽  
Oxidative Capacity ◽  
Control Group ◽  
Diabetic Patients ◽  
Type 2 Diabetic Patients ◽  
Patients With Diabetes ◽  
Total Antioxidant

Aim. To study Actovegin efficacy in oxidative stress (OS) correction at diabetic polyneuropathy (DPN) in patients with diabetes mellitus type 2 (DM2)and arterial hypertension (AH).Materials and Methods. 51 patients (24 women and 27 men) aged 53.4?0.7 with the average duration of DM2 5.6?0.2 years, DPN - 4.9?0.2years and AH - 6.0?0.2 years were examined. Daily albuminuria, glomerular filtration rate (GRF) were evaluated, standard methods for diagnosisof DPN were used. 26 patients took Actovegin therapy during 6-8 weeks, the rest 25 patients were in the control group. Parameters of the OS werestudied. Results. The increase of total oxidative capacity, the decrease of total antioxidant capacity and the rise of levels of antibodies to oxidated LDL wererevealed in patients with DM2, DPN and AH. Antioxidant and anti-hypoxic effects of 400 mg/day of Actovegin were established in this group of patients.Conclusions. Actovegin impacts oxidative stress parameters and improves the clinical manifestation of diabetic polyneuropathy.

scholarly journals Iodine speciation and size distribution in ambient aerosols at a coastal new particle formation hotspot in China

2019 ◽  
Vol 19 (6) ◽  
pp. 4025-4039 ◽  
Author(s):  
Huan Yu ◽  
Lili Ren ◽  
Xiangpeng Huang ◽  
Mingjie Xie ◽  
Jun He ◽  
...  
Keyword(s):  
Particle Formation ◽  
Coastal Areas ◽  
Aerosol Sample ◽  
Size Distributions ◽  
New Particle Formation ◽  
Nucleation Mode ◽  
Iodine Species ◽  
Organic Iodine ◽  
Iodine Compounds ◽  
Iodine Speciation

Abstract. Intense new particle formation (NPF) events were observed in the coastal atmosphere during algae growth and farming season at Xiangshan gulf of the east China coast. High nucleation-mode iodine concentrations measured by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) confirmed that the NPF events were induced by iodine species. Our study provides important information on iodine speciation, size distributions, and its role in NPF in the context of heavy air pollution in China's coastal areas. For the first time, we identified 5 inorganic iodine species, 45 organic iodine compounds (35 molecular formulas), and a group of iodide–organic adducts in aerosols. The concentrations and size distributions of iodine species down to 10 nm were measured during the iodine-induced NPF, continental NPF, and non-NPF days at the coastal site and compared to those at an inland site. The iodine in the above four aerosol sample types were characterized by iodate, aromatic iodine compounds, iodoacetic acid or iodopropenoic acid, and iodide–organic adducts, respectively. Iodide and organic iodine compounds were found in the nucleation-mode particles; however, it is still not clear whether they contributed to nucleation or just new particle growth. Wild algae, as well as farmed algae, could be an important NPF source in China's coastal areas.

scholarly journals Erratum

1968 ◽  
Vol 14 (6) ◽  
pp. 582-582
Keyword(s):  
Distilled Water ◽  
Serum Thyroxine ◽  
Organic Iodine ◽  
Final Volume ◽  
Iodine Compounds

Abstract The article "Determination of Organic Iodine Compounds in Serum: IV. A New Nonincineration Technic for Serum Thyroxine" by Vincent J. Pileggi and Gerald Kessler—Clin. Chem. 14, 339 (1968)—contains an error. On page 340, under Reagents, the preparation of the bromate-bromide reagent should read: Bromate-bromide reagent (0.1 M KBrO3, 0.6 M KBr) KBrO3, 1.67 gm., and KBr, 7.14 gui., are dissolved in distilled water, and the solution made to a final volume of 100 ml.

scholarly journals A novel flavin derivative reveals the impact of glucose on oxidative stress in adipocytes

2014 ◽  
Vol 50 (60) ◽  
pp. 8181-8184 ◽  
Author(s):  
Jonathan Yeow ◽  
Amandeep Kaur ◽  
Matthew D. Anscomb ◽  
Elizabeth J. New
Keyword(s):  
Oxidative Stress ◽  
Redox State ◽  
Fluorescent Sensor ◽  
Oxidative Capacity ◽  
Biologically Relevant ◽  
Oxidation Reduction ◽  
The Impact

A fluorescent sensor for redox state shows reversible oxidation/reduction at biologically-relevant potentials, and is used to visualise cellular oxidative capacity.

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