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Yao Z, Morrison G. Reactive oxygen species on indoor surfaces. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024; 26:1198-1204. [PMID: 38805261 DOI: 10.1039/d4em00031e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Reactive oxygen species (ROS) are relatively unstable oxygen-containing radicals or non-radicals, some of which may react with tissues and biomolecules after entering the body. ROS is present in indoor aerosols, but it is unclear how much of that ROS is of indoor origin. Indoor surface films have been hypothesized to be a major source of the ROS observed on indoor aerosols. In this study, the ROS concentration on residential indoor surfaces was measured using a xylenol orange ferrous oxidation assay after wiping and extraction. On genuine surfaces frequently touched by apartment occupants, the concentration was >0.2 nmol cm-2; infrequently touched surfaces were at or below detection limits. On clean glass plates that had been deployed in apartments for 6 weeks, horizontal plates had higher concentrations than vertically oriented plates. The highest concentration, 1.3 nmol cm-2, was observed on a horizontally oriented plate close to an electric stove. To simulate the dynamic oxidation of unsaturated hydrocarbons on indoor surfaces, a surface lipid mixture (SLM) was dosed on 19 glass plates which were then exposed to untreated laboratory air for periods ranging from 1 to 56 days. During the first 5-6 days, the ROS concentration increased roughly linearly to a maximum of 5-6 nmol cm-2. Then the concentration ceased to increase, perhaps because reactive sites had become depleted. After 2 weeks, ROS decreased slowly, possibly due to a combination of volatilization, decomposition and continued formation by autoxidation. These field and laboratory results support the hypothesis that indoor surfaces can be a source of ROS.
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Affiliation(s)
- Zhenduo Yao
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Glenn Morrison
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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2
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Yang S, Licina D. Nanocluster Aerosols from Ozone-Human Chemistry Are Dominated by Squalene-Ozone Reactions. ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 2024; 11:716-722. [PMID: 39006814 PMCID: PMC11238579 DOI: 10.1021/acs.estlett.4c00289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/14/2024] [Accepted: 06/10/2024] [Indexed: 07/16/2024]
Abstract
Nanocluster aerosols (NCAs, <3 nm particles) are associated with climate feedbacks and potentially with human health. Our recent study revealed NCA formation owing to the reaction of ozone with human surfaces. However, the underlying mechanisms driving NCA emissions remain unexplored. Squalene is the most abundant compound in human skin lipids that reacts with ozone, followed by unsaturated fatty acids. This study aims to examine the contribution of the squalene-ozone reaction to NCA formation and the influence of ozone and ammonia (NH3) levels. In a climate-controlled chamber, we painted squalene and 6-hexadecenoic acid (C16:1n6) on glass plates to facilitate their reactions with ozone. The squalene-ozone reaction was further investigated at different ozone levels (15 and 90 ppb) and NH3 levels (0 and 375 ppb). The results demonstrate that the ozonolysis of human skin lipid compounds contributes to NCA formation. With a typical squalene-C16:1n6 ratio found in human skin lipids (4:1), squalene generated 40 times more NCAs than did C16:1n6 and, thus, dominated NCA formation. More NCAs were generated with increased ozone levels, whereas increased NH3 levels were associated with the stronger generation of larger NCAs but fewer of the smallest ones. This study experimentally confirms that NCAs are primarily formed from squalene-ozone reactions in ozone-human chemistry.
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Affiliation(s)
- Shen Yang
- Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Dusan Licina
- Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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3
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Amini P, Okeme JO. Tear Fluid as a Matrix for Biomonitoring Environmental and Chemical Exposures. Curr Environ Health Rep 2024:10.1007/s40572-024-00454-7. [PMID: 38967858 DOI: 10.1007/s40572-024-00454-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2024] [Indexed: 07/06/2024]
Abstract
PURPOSE Exposures to hazardous chemicals have been linked to many detrimental health effects and it is therefore critical to have effective biomonitoring methods to better evaluate key environmental exposures that increase the risk of chronic disease and death. Traditional biomonitoring utilizing blood and urine is limited due to the specialized skills and invasiveness of collecting these fluid samples. This systematic review focuses on tear fluid, which is largely under-researched, as a promising complementary matrix to the traditional fluids used for biomonitoring. The objective is to evaluate the practicability of using human tear fluid for biomonitoring environmental exposures, highlighting potential pitfalls and opportunities. RECENT FINDING Tear fluid biomonitoring represents a promising method for assessing exposures because it can be collected with minimal invasiveness and tears contain exposure markers from both the external and internal environments. Tear fluid uniquely interfaces with the external environment at the air-tear interface, providing a surface for airborne chemicals to diffuse into the ocular environment and interact with biomolecules. Tear fluid also contains molecules from the internal environment that have travelled from the blood to tears by crossing the blood-tear barrier. This review demonstrates that tear fluid can be used to identify hazardous chemicals from the external environment and differentiate exposure groups.
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Affiliation(s)
- Parshawn Amini
- Department of Chemistry & Chemical Biology, McMaster University, Hamilton, ON, Ontario, L8S 4L8, Canada
| | - Joseph O Okeme
- Department of Chemistry & Chemical Biology, McMaster University, Hamilton, ON, Ontario, L8S 4L8, Canada.
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4
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Zeng M, Wilson KR. Evaluating Possible Formation Mechanisms of Criegee Intermediates during the Heterogeneous Autoxidation of Squalene. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:11587-11595. [PMID: 38900151 DOI: 10.1021/acs.est.4c02590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Organic molecules in the environment oxidatively degrade by a variety of free radical, microbial, and biogeochemical pathways. A significant pathway is heterogeneous autoxidation, in which degradation occurs via a network of carbon and oxygen centered free radicals. Recently, we found evidence for a new heterogeneous autoxidation mechanism of squalene that is initiated by hydroxyl (OH) radical addition to a carbon-carbon double bond and apparently propagated through pathways involving Criegee Intermediates (CI) produced from β-hydroxy peroxy radicals (β-OH-RO2•). It remains unclear, however, exactly how CI are formed from β-OH-RO2•, which could occur by a unimolecular or bimolecular pathway. Combining kinetic models and multiphase OH oxidation measurements of squalene, we evaluate the kinetic viability of three mechanistic scenarios. Scenario 1 assumes that CI are formed by the unimolecular bond scission of β-OH-RO2•, whereas Scenarios 2 and 3 test bimolecular pathways of β-OH-RO2• to yield CI. Scenario 1 best replicates the entire experimental data set, which includes effective uptake coefficients vs [OH] as well as the formation kinetics of the major products (i.e., aldehydes and secondary ozonides). Although the unimolecular pathway appears to be kinetically viable, future high-level theory is needed to fully explain the mechanistic relationship between CI and β-OH-RO2• in the condensed phase.
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Affiliation(s)
- Meirong Zeng
- College of Smart Energy, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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5
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Gautam T, Kim E, Ng L, Choudhary V, Lima Amorim J, Loebel Roson M, Zhao R. Photooxidation-Initiated Aqueous-Phase Formation of Organic Peroxides: Delving into Formation Mechanisms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6564-6574. [PMID: 38578220 DOI: 10.1021/acs.est.3c01162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/06/2024]
Abstract
Formation of highly oxygenated molecules (HOMs) such as organic peroxides (ROOR, ROOH, and H2O2) is known to degrade food and organic matter. Gas-phase unimolecular autoxidation and bimolecular RO2 + HO2/RO2 reactions are prominently renowned mechanisms associated with the formation of peroxides. However, the reaction pathways and conditions favoring the generation of peroxides in the aqueous phase need to be evaluated. Here, we identified bulk aqueous-phase ROOHs in varying organic precursors, including a laboratory model compound and monoterpene oxidation products. Our results show that formation of ROOHs is suppressed at enhanced oxidant concentrations but exhibits complex trends at elevated precursor concentrations. Furthermore, we observed an exponential increase in the yield of ROOHs when UV light with longer wavelengths was used in the experiment, comparing UVA, UVB, and UVC. Water-soluble organic compounds represent a significant fraction of ambient cloud-water components (up to 500 μM). Thus, the reaction pathways facilitating the formation of HOMs (i.e., ROOHs) during the aqueous-phase oxidation of water-soluble species add to the climate and health burden of atmospheric particulate matter.
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Affiliation(s)
- Tania Gautam
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Erica Kim
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Lisa Ng
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Vikram Choudhary
- Air Pollution Exposure Laboratory, Division of Respiratory Medicine, Department of Medicine, Vancouver Coastal Health Research Institute, The University of British Columbia, Vancouver, British Columbia V5Z1W9, Canada
| | - Jessica Lima Amorim
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Max Loebel Roson
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Ran Zhao
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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6
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Langer S, Weschler CJ, Bekö G, Morrison G, Sjöblom A, Giovanoulis G, Wargocki P, Wang N, Zannoni N, Yang S, Williams J. Squalene Depletion in Skin Following Human Exposure to Ozone under Controlled Chamber Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6693-6703. [PMID: 38577981 DOI: 10.1021/acs.est.3c09394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/06/2024]
Abstract
A major component of human skin oil is squalene, a highly unsaturated hydrocarbon that protects the skin from atmospheric oxidants. Skin oil, and thus squalene, is continuously replenished on the skin surface. Squalene is also quickly consumed through reactions with ozone and other oxidants. This study examined the extent of squalene depletion in the skin oils of the forearm of human volunteers after exposure to ozone in a climate chamber. Temperature, relative humidity (RH), skin coverage by clothing, and participants' age were varied in a controlled manner. Concentrations of squalene were determined in skin wipe samples collected before and after ozone exposure. Exposures to ozone resulted in statistically significant decreases in post-exposure squalene concentrations compared to pre-exposure squalene concentrations in the skin wipes when squalene concentrations were normalized by concentrations of co-occurring cholesterol but not by co-occurring pyroglutamic acid (PGA). The rate of squalene loss due to ozonolysis was lower than its replenishment on the skin surface. Within the ranges examined, temperature and RH did not significantly affect the difference between normalized squalene levels in post-samples versus pre-samples. Although not statistically significant, skin coverage and age of the volunteers (three young adults, three seniors, and three teenagers) did appear to impact squalene depletion on the skin surfaces.
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Affiliation(s)
- Sarka Langer
- IVL Swedish Environmental Research Institute, Environmental Chemistry, 40014 Göteborg, Sweden
- Chalmers University of Technology, Department of Architecture and Civil Engineering, Division Building Services Engineering, 412 96 Göteborg, Sweden
| | - Charles J Weschler
- Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, New Jersey 08854, United States
- International Centre for Indoor Environment and Energy, Department of Environmental and Resource Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Gabriel Bekö
- International Centre for Indoor Environment and Energy, Department of Environmental and Resource Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
- Healthy and Sustainable Built Environment Research Centre, Ajman University, P.O. Box 346 Ajman, United Arab Emirates
| | - Glenn Morrison
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7431, United States
| | - Ann Sjöblom
- IVL Swedish Environmental Research Institute, Environmental Chemistry, 40014 Göteborg, Sweden
| | - Georgios Giovanoulis
- IVL Swedish Environmental Research Institute, Environmental Chemistry, 40014 Göteborg, Sweden
| | - Pawel Wargocki
- International Centre for Indoor Environment and Energy, Department of Environmental and Resource Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Nijing Wang
- Atmospheric Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - Nora Zannoni
- Atmospheric Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - Shen Yang
- Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Jonathan Williams
- Atmospheric Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
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7
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Yang S, Müller T, Wang N, Bekö G, Zhang M, Merizak M, Wargocki P, Williams J, Licina D. Influence of Ventilation on Formation and Growth of 1-20 nm Particles via Ozone-Human Chemistry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:4704-4715. [PMID: 38326946 PMCID: PMC10938884 DOI: 10.1021/acs.est.3c08466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 01/26/2024] [Accepted: 01/29/2024] [Indexed: 02/09/2024]
Abstract
Ozone reaction with human surfaces is an important source of ultrafine particles indoors. However, 1-20 nm particles generated from ozone-human chemistry, which mark the first step of particle formation and growth, remain understudied. Ventilation and indoor air movement could have important implications for these processes. Therefore, in a controlled-climate chamber, we measured ultrafine particles initiated from ozone-human chemistry and their dependence on the air change rate (ACR, 0.5, 1.5, and 3 h-1) and operation of mixing fans (on and off). Concurrently, we measured volatile organic compounds (VOCs) and explored the correlation between particles and gas-phase products. At 25-30 ppb ozone levels, humans generated 0.2-7.7 × 1012 of 1-3 nm, 0-7.2 × 1012 of 3-10 nm, and 0-1.3 × 1012 of 10-20 nm particles per person per hour depending on the ACR and mixing fan operation. Size-dependent particle growth and formation rates increased with higher ACR. The operation of mixing fans suppressed the particle formation and growth, owing to enhanced surface deposition of the newly formed particles and their precursors. Correlation analyses revealed complex interactions between the particles and VOCs initiated by ozone-human chemistry. The results imply that ventilation and indoor air movement may have a more significant influence on particle dynamics and fate relative to indoor chemistry.
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Affiliation(s)
- Shen Yang
- Human-Oriented
Built Environment Lab, School of Architecture, Civil and Environmental
Engineering, École Polytechnique
Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Tatjana Müller
- Max
Planck Institute for Chemistry, Hahn-Meitner Weg 1, 55128 Mainz, Germany
| | - Nijing Wang
- Max
Planck Institute for Chemistry, Hahn-Meitner Weg 1, 55128 Mainz, Germany
| | - Gabriel Bekö
- International
Centre for Indoor Environment and Energy, Department of Environmental
and Resource Engineering, Technical University
of Denmark, 2800 Kongens Lyngby, Denmark
| | - Meixia Zhang
- Human-Oriented
Built Environment Lab, School of Architecture, Civil and Environmental
Engineering, École Polytechnique
Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
- School
of Mechanical Engineering, Beijing Institute
of Technology, 100081 Beijing, China
| | - Marouane Merizak
- Human-Oriented
Built Environment Lab, School of Architecture, Civil and Environmental
Engineering, École Polytechnique
Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Pawel Wargocki
- International
Centre for Indoor Environment and Energy, Department of Environmental
and Resource Engineering, Technical University
of Denmark, 2800 Kongens Lyngby, Denmark
| | - Jonathan Williams
- Max
Planck Institute for Chemistry, Hahn-Meitner Weg 1, 55128 Mainz, Germany
- Energy,
Environment and Water Research Center, The
Cyprus Institute, 2121 Nicosia, Cyprus
| | - Dusan Licina
- Human-Oriented
Built Environment Lab, School of Architecture, Civil and Environmental
Engineering, École Polytechnique
Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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8
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Li F, Mi Y, Chen RZN, Liu W, Wu J, Hou D, Yang M, Zhang S. A radical polymer membrane for simultaneous degradation of organic pollutants and water filtration. Proc Natl Acad Sci U S A 2024; 121:e2315688121. [PMID: 38315857 PMCID: PMC10873639 DOI: 10.1073/pnas.2315688121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Accepted: 12/14/2023] [Indexed: 02/07/2024] Open
Abstract
Integrating reactive radicals into membranes that resemble biological membranes has always been a pursuit for simultaneous organics degradation and water filtration. In this research, we discovered that a radical polymer (RP) that can directly trigger the oxidative degradation of sulfamethozaxole (SMX). Mechanistic studies by experiment and density functional theory simulations revealed that peroxyl radicals are the reactive species, and the radicals could be regenerated in the presence of O2. Furthermore, an interpenetrating RP network membrane consisting of polyvinyl alcohol and the RP was fabricated to demonstrate the simultaneous filtration of large molecules in the model wastewater stream and the degradation of ~ 85% of SMX with a steady permeation flux. This study offers valuable insights into the mechanism of RP-triggered advanced oxidation processes and provides an energy-efficient solution for the degradation of organic compounds and water filtration in wastewater treatment.
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Affiliation(s)
- Feng Li
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore117585, Singapore
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
| | - Yixin Mi
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore117585, Singapore
| | - Ronn Zhi Ning Chen
- National University of Singapore High School of Mathematics and Sciences, Singapore129957, Singapore
| | - Wei Liu
- School of Physics, Frontiers Science Center for Mobile Information Communication and Security, Quantum Information Research Center, Southeast University, Nanjing211189, China
- Purple Mountain Laboratories, Nanjing211111, China
| | - Ji Wu
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore117585, Singapore
| | - Deyin Hou
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
| | - Min Yang
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
| | - Sui Zhang
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore117585, Singapore
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9
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Chen JY, Kuruparan A, Zamani-Babgohari M, Gonzales-Vigil E. Dynamic changes to the plant cuticle include the production of volatile cuticular wax-derived compounds. Proc Natl Acad Sci U S A 2023; 120:e2307012120. [PMID: 38019866 PMCID: PMC10710056 DOI: 10.1073/pnas.2307012120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Accepted: 10/10/2023] [Indexed: 12/01/2023] Open
Abstract
The cuticle is a hydrophobic structure that seals plant aerial surfaces from the surrounding environment. To better understand how cuticular wax composition changes over development, we conducted an untargeted screen of leaf surface lipids from black cottonwood (Populus trichocarpa). We observed major shifts to the lipid profile across development, from a phenolic and terpene-dominated profile in young leaves to an aliphatic wax-dominated profile in mature leaves. Contrary to the general pattern, levels of aliphatic cis-9-alkenes decreased in older leaves following their accumulation. A thorough examination revealed that the decrease in cis-9-alkenes was accompanied by a concomitant increase in aldehydes, one of them being the volatile compound nonanal. By applying exogenous alkenes to P. trichocarpa leaves, we show that unsaturated waxes in the cuticle undergo spontaneous oxidative cleavage to generate aldehydes and that this process occurs similarly in other alkene-accumulating systems such as balsam poplar (Populus balsamifera) leaves and corn (Zea mays) silk. Moreover, we show that the production of cuticular wax-derived compounds can be extended to other wax components. In bread wheat (Triticum aestivum), 9-hydroxy-14,16-hentriacontanedione likely decomposes to generate 2-heptadecanone and 7-octyloxepan-2-one (a caprolactone). These findings highlight an unusual route to the production of plant volatiles that are structurally encoded within cuticular wax precursors. These processes could play a role in modulating ecological interactions and open the possibility for engineering bioactive volatile compounds into plant waxes.
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Affiliation(s)
- Jeff Y Chen
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON M1C 1A4, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Aswini Kuruparan
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON M1C 1A4, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Mahbobeh Zamani-Babgohari
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON M1C 1A4, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Eliana Gonzales-Vigil
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON M1C 1A4, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
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10
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Zhou Z, Crilley LR, Ditto JC, VandenBoer TC, Abbatt JPD. Chemical Fate of Oils on Indoor Surfaces: Ozonolysis and Peroxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:15546-15557. [PMID: 37647222 DOI: 10.1021/acs.est.3c04009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Unsaturated triglycerides found in food and skin oils are reactive in ambient air. However, the chemical fate of such compounds has not been well characterized in genuine indoor environments. Here, we monitored the aging of oil coatings on glass surfaces over a range of environmental conditions, using mass spectrometry, nuclear magnetic resonance (NMR), and electron paramagnetic resonance (EPR) techniques. Upon room air exposure (up to 17 ppb ozone), the characteristic ozonolysis products, secondary ozonides, were observed on surfaces near the cooking area of a commercial kitchen, along with condensed-phase aldehydes. In an office setting, ozonolysis is also the dominant degradation pathway for oil films exposed to air. However, for indoor enclosed spaces such as drawers, the depleted air flow makes lipid autoxidation more favorable after an induction period of a few days. Forming hydroperoxides as the major primary products, this radical-mediated peroxidation behavior is accelerated by indoor direct sunlight, but the initiation step in dark settings is still unclear. These results are in accord with radical measurements, indicating that indoor photooxidation facilitates radical formation on surfaces. Overall, many intermediate and end products observed are reactive oxygen species (ROS) that may induce oxidative stress in human bodies. Given that these species can be widely found on both food and household surfaces, their toxicological properties are worth further attention.
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Affiliation(s)
- Zilin Zhou
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Leigh R Crilley
- Department of Chemistry, York University, Toronto, Ontario M3J 1P3, Canada
| | - Jenna C Ditto
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | | | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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11
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Weschler CJ, Nazaroff WW. Ozone Loss: A Surrogate for the Indoor Concentration of Ozone-Derived Products. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:13569-13578. [PMID: 37639667 DOI: 10.1021/acs.est.3c03968] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Ozone concentrations tend to be substantially lower indoors than outdoors, largely because of ozone reactions with indoor surfaces. When there are no indoor sources of ozone, a common condition, the net concentration of gaseous products derived from indoor ozone chemistry scales linearly with the difference between outdoor and indoor ozone concentrations, termed "ozone loss." As such, ozone loss is a metric that might be used by epidemiologists to disentangle the adverse health effects of ozone's oxidation products from those of exposure to ozone itself. The present paper examines the characteristics, potential utility, and limitations of the ozone loss concept. We show that for commonly occurring indoor conditions, the ozone loss concentration is directly proportional to the total rate constant for ozone removal on surfaces (ksum) and inversely proportional to the net removal of ozone by air exchange (λ) plus surface reactions (ksum). It follows that the ratio of indoor ozone to ozone loss is equal to the ratio of λ to ksum. Ozone loss is a promising metric for probing potential adverse health effects resulting from exposures to products of indoor ozone chemistry. Notwithstanding its virtues, practitioners using it should be mindful of the limitations discussed in this paper.
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Affiliation(s)
- Charles J Weschler
- Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, New Jersey 08854, United States
- International Centre for Indoor Environment and Energy, Technical University of Denmark, Lyngby 2800, Denmark
| | - William W Nazaroff
- Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720-1710, United States
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12
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Zhang W, Zhao Z, Shen C, Zhang H. Unexpectedly Efficient Aging of Organic Aerosols Mediated by Autoxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:6965-6974. [PMID: 37083304 DOI: 10.1021/acs.est.2c09773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Multiphase oxidative aging is a ubiquitous process for atmospheric organic aerosols (OA). But its kinetics was often found to be slow in previous laboratory studies where high hydroxyl radical concentrations ([•OH]) were used. In this study, we performed heterogeneous oxidation experiments of several model OA systems under varied aging timescales and gas-phase [•OH]. Our results suggest that OA heterogeneous oxidation may be 2-3 orders of magnitude faster when [•OH] is decreased from typical laboratory flow tube conditions to atmospheric levels. Direct laboratory mass spectrometry measurements coupled with kinetic simulations suggest that an intermolecular autoxidation mechanism mediated by particle-phase peroxy radicals greatly accelerates OA oxidation, with enhanced formation of organic hydroperoxides, alcohols, and fragmentation products. With autoxidation, we estimate that the OA oxidation timescale in the atmosphere may be from less than a day to several days. Thus, OA oxidative aging can have greater atmospheric impacts than previously expected. Furthermore, our findings reveal the nature of heterogeneous aerosol oxidation chemistry in the atmosphere and help improve the understanding and prediction of atmospheric OA aging and composition evolution.
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Affiliation(s)
- Wen Zhang
- Department of Chemistry, University of California, Riverside, California 92507, United States
| | - Zixu Zhao
- Department of Chemistry, University of California, Riverside, California 92507, United States
| | - Chuanyang Shen
- Department of Chemistry, University of California, Riverside, California 92507, United States
| | - Haofei Zhang
- Department of Chemistry, University of California, Riverside, California 92507, United States
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13
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He J, Zhang H, Liu Y, Ju Y, He Y, Jiang Y, Jiang J. Interfacial Extraction to Trap and Characterize the Criegee Intermediates from Phospholipid Ozonolysis. Anal Chem 2023; 95:5018-5023. [PMID: 36840931 DOI: 10.1021/acs.analchem.2c05472] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
Criegee intermediates (CIs) play a significant role in cell membrane peroxidation, but their identification remains elusive at the molecular level. Herein, we combined interfacial extraction and sonic spray ionization mass spectrometry to study the oxidation reaction of 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (POPG) mediated by ozone (O3) at/near the surface of a hung water droplet. On-line interfacial extraction and ionization provided a snapshot of the short-lived CIs. Experiments in which the content of water was varied provided evidence for the formation of CIs, which has not been previously observed. Capture experiments using 5,5-dimethyl-pyrroline N-oxide (DMPO) indicated that CIs could be selectively characterized, and the extracted ion current (EICs) of CIs vs DMPO-CI adducts further confirmed the successful observation of CIs. Theoretical calculation suggested that surface ozonolysis of POPG was mainly mediated by anti-CI. These results open a new route for aqueous surface reactive species identification, and benefit toward the understanding of disease development associated with cell oxidative stress mediated by CIs.
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Affiliation(s)
- Jing He
- School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai 264209, Shandong, China
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150090, Heilongjiang, China
| | - Hong Zhang
- School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai 264209, Shandong, China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, China
| | - Yaqi Liu
- School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai 264209, Shandong, China
| | - Yun Ju
- School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai 264209, Shandong, China
| | - Yuwei He
- School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai 264209, Shandong, China
| | - Yanxiao Jiang
- School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai 264209, Shandong, China
| | - Jie Jiang
- School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai 264209, Shandong, China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, China
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150090, Heilongjiang, China
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14
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Hu Z, Di Q, Liu B, Li Y, He Y, Zhu Q, Xu Q, Dagaut P, Hansen N, Sarathy SM, Xing L, Truhlar DG, Wang Z. Elucidating the photodissociation fingerprint and quantifying the determination of organic hydroperoxides in gas-phase autoxidation. Proc Natl Acad Sci U S A 2023; 120:e2220131120. [PMID: 36848575 PMCID: PMC10013783 DOI: 10.1073/pnas.2220131120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 01/12/2023] [Indexed: 03/01/2023] Open
Abstract
Hydroperoxides are formed in the atmospheric oxidation of volatile organic compounds, in the combustion autoxidation of fuel, in the cold environment of the interstellar medium, and also in some catalytic reactions. They play crucial roles in the formation and aging of secondary organic aerosols and in fuel autoignition. However, the concentration of organic hydroperoxides is seldom measured, and typical estimates have large uncertainties. In this work, we developed a mild and environmental-friendly method for the synthesis of alkyl hydroperoxides (ROOH) with various structures, and we systematically measured the absolute photoionization cross-sections (PICSs) of the ROOHs using synchrotron vacuum ultraviolet-photoionization mass spectrometry (SVUV-PIMS). A chemical titration method was combined with an SVUV-PIMS measurement to obtain the PICS of 4-hydroperoxy-2-pentanone, a typical molecule for combustion and atmospheric autoxidation ketohydroperoxides (KHPs). We found that organic hydroperoxide cations are largely dissociated by loss of OOH. This fingerprint was used for the identification and accurate quantification of the organic peroxides, and it can therefore be used to improve models for autoxidation chemistry. The synthesis method and photoionization dataset for organic hydroperoxides are useful for studying the chemistry of hydroperoxides and the reaction kinetics of the hydroperoxy radicals and for developing and evaluating kinetic models for the atmospheric autoxidation and combustion autoxidation of the organic compounds.
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Affiliation(s)
- Zhihong Hu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui230029, P. R. China
| | - Qimei Di
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui230029, P. R. China
| | - Bingzhi Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui230029, P. R. China
| | - Yanbo Li
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui230029, P. R. China
| | - Yunrui He
- Energy and Power Engineering Institute, Henan University of Science and Technology, Luoyang, Henan471003, China
| | - Qingbo Zhu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui230029, P. R. China
| | - Qiang Xu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui230029, P. R. China
| | - Philippe Dagaut
- CNRS, Institut National des Sciences de l’Ingénierie et des Systèmes, Institut de Combustion, Aérothermique, Réactivité et Environnement, Orléans45071, cedex 2, France
| | - Nils Hansen
- Combustion Research Facility, Sandia National Laboratories, Livermore, CA94551
| | - S. Mani Sarathy
- King Abdullah University of Science and Technology, Clean Combustion Research Center, Thuwal23955-6900, Saudi Arabia
| | - Lili Xing
- Energy and Power Engineering Institute, Henan University of Science and Technology, Luoyang, Henan471003, China
| | - Donald G. Truhlar
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN55455-0431
| | - Zhandong Wang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui230029, P. R. China
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, Anhui230026, P. R. China
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15
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Medvedko S, Ströbele M, Wagner JP. Synthesis of Sterically Encumbered Thiourea S-Oxides through Direct Thiourea Oxidation. Chemistry 2023; 29:e202203005. [PMID: 36279187 PMCID: PMC10107457 DOI: 10.1002/chem.202203005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Indexed: 11/07/2022]
Abstract
Thiourea S-oxides can be viewed as formal analogs of the currently unknown diamino-substituted Criegee intermediates (urea O-oxides). However, the preparation of such S-oxides is rather challenging, and the direct oxidation of thioureas typically only leads to formation of desulfurized products. Employing the accurate revDSD-PBEP86-D4 double hybrid density functional, it was found that the peracid mediated oxidation of thiourea S-oxides exhibits a lower reaction barrier than the oxidation of the corresponding thiourea itself in contrast to most other ordinary thioketones. The undesired overoxidation reactivity, which is associated with strong π-donation from the thiourea's nitrogen atoms, can be partially suppressed by introduction of bulky substituents and the utilization of protic solvents. In this regard, we managed to prepare two sterically encumbered thiourea S-oxides in isolated yields of 35-40 %. The S-oxides are stable in the solid state and in alcoholic solutions at room temperature for extended periods of time, but swiftly decompose in aprotic solvents by disproportionation. A dimesityl-substituted thiourea S-oxide complexed with residual mCBA could be characterized by means of X-ray crystallography, confirming the importance of hydrogen bonding in the stabilization of the amino-substituted C=S+ -O- moiety.
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Affiliation(s)
- Serhii Medvedko
- Institut für Organische Chemie, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany.,Department of Organic Chemistry, National Technical University of Ukraine, Igor Sikorsky Kyiv Polytechnic Institute, Peremohy Ave 37, 03056, Kyiv, Ukraine
| | - Markus Ströbele
- Institut für Anorganische Chemie, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - J Philipp Wagner
- Institut für Organische Chemie, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
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16
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Wang S, Zhao Y, Chan AWH, Yao M, Chen Z, Abbatt JPD. Organic Peroxides in Aerosol: Key Reactive Intermediates for Multiphase Processes in the Atmosphere. Chem Rev 2023; 123:1635-1679. [PMID: 36630720 DOI: 10.1021/acs.chemrev.2c00430] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Organic peroxides (POs) are organic molecules with one or more peroxide (-O-O-) functional groups. POs are commonly regarded as chemically labile termination products from gas-phase radical chemistry and therefore serve as temporary reservoirs for oxidative radicals (HOx and ROx) in the atmosphere. Owing to their ubiquity, active gas-particle partitioning behavior, and reactivity, POs are key reactive intermediates in atmospheric multiphase processes determining the life cycle (formation, growth, and aging), climate, and health impacts of aerosol. However, there remain substantial gaps in the origin, molecular diversity, and fate of POs due to their complex nature and dynamic behavior. Here, we summarize the current understanding on atmospheric POs, with a focus on their identification and quantification, state-of-the-art analytical developments, molecular-level formation mechanisms, multiphase chemical transformation pathways, as well as environmental and health impacts. We find that interactions with SO2 and transition metal ions are generally the fast PO transformation pathways in atmospheric liquid water, with lifetimes estimated to be minutes to hours, while hydrolysis is particularly important for α-substituted hydroperoxides. Meanwhile, photolysis and thermolysis are likely minor sinks for POs. These multiphase PO transformation pathways are distinctly different from their gas-phase fates, such as photolysis and reaction with OH radicals, which highlights the need to understand the multiphase partitioning of POs. By summarizing the current advances and remaining challenges for the investigation of POs, we propose future research priorities regarding their origin, fate, and impacts in the atmosphere.
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Affiliation(s)
- Shunyao Wang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai200444, China
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, OntarioM5S 3E5, Canada
| | - Yue Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Arthur W H Chan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, OntarioM5S 3E5, Canada
- School of the Environment, University of Toronto, Toronto, OntarioM5S 3E8, Canada
| | - Min Yao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Zhongming Chen
- State Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing100871, China
| | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, Toronto, OntarioM5S 3H6, Canada
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17
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Qiu J, Fujita M, Tonokura K, Enami S. Stability of Terpenoid-Derived Secondary Ozonides in Aqueous Organic Media. J Phys Chem A 2022; 126:5386-5397. [PMID: 35921086 PMCID: PMC9393869 DOI: 10.1021/acs.jpca.2c04077] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
1,2,4-Trioxolanes, known as secondary ozonides (SOZs), are key products of ozonolysis of biogenic terpenoids. Functionalized terpenoid-derived SOZs are readily taken up into atmospheric aerosols; however, their condensed-phase fates remain unknown. Here, we report the results of a time-dependent mass spectrometric investigation into the liquid-phase fates of C10 and C13 SOZs synthesized by ozonolysis of a C10 monoterpene alcohol (α-terpineol) in water:acetone (1:1 = vol:vol) mixtures. Isomerization of Criegee intermediates and bimolecular reaction of Criegee intermediates with acetone produced C10 and C13 SOZs, respectively, which were detected as their Na+-adducts by positive-ion electrospray mass spectrometry. Use of CD3COCD3, D2O, and H218O solvents enabled identification of three types of C13 SOZs (aldehyde, ketone, and lactol) and other products. These SOZs were surprisingly stable in water:acetone (1:1) mixtures at T = 298 K, with some persisting for at least a week. Theoretical calculations supported the high stability of the lactol-type C13 SOZ formed from the aldehyde-type C13 SOZ via intramolecular rearrangement. The present results suggest that terpenoid-derived SOZs can persist in atmospheric condensed phases, potentially until they are delivered to the epithelial lining fluid of the pulmonary alveoli via inhaled particulate matter, where they may exert hitherto unrecognized adverse health effects.
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Affiliation(s)
- Junting Qiu
- Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563, Japan
| | - Michiya Fujita
- Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563, Japan
| | - Kenichi Tonokura
- Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563, Japan
| | - Shinichi Enami
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan
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18
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Willis MD, Wilson KR. Coupled Interfacial and Bulk Kinetics Govern the Timescales of Multiphase Ozonolysis Reactions. J Phys Chem A 2022; 126:4991-5010. [PMID: 35863113 DOI: 10.1021/acs.jpca.2c03059] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Chemical transformations in aerosols impact the lifetime of particle phase species, the fate of atmospheric pollutants, and both climate- and health-relevant aerosol properties. Timescales for multiphase reactions of ozone in atmospheric aqueous phases are governed by coupled kinetic processes between the gas phase, the particle interface, and its bulk, which respond dynamically to reactive consumption of O3. However, models of atmospheric aerosol reactivity often do not account for the coupled nature of multiphase processes. To examine these dynamics, we use new and prior experimental observations of aqueous droplet reaction kinetics, including three systems with a range of surface affinities and ozonolysis rate coefficients (trans-aconitic acid (C6H6O6), maleic acid (C4H4O4), and sodium nitrite (NaNO2)). Using literature rate coefficients and thermodynamic properties, we constrain a simple two-compartment stochastic kinetic model which resolves the interface from the particle bulk and represents O3 partitioning, diffusion, and reaction as a coupled kinetic system. Our kinetic model accurately predicts decay kinetics across all three systems, demonstrating that both the thermodynamic properties of O3 and the coupled kinetic and diffusion processes are key to making accurate predictions. An enhanced concentration of adsorbed O3, compared to gas and bulk phases is rapidly maintained and remains constant even as O3 is consumed by reaction. Multiphase systems dynamically seek to achieve equilibrium in response to reactive O3 loss, but this is hampered at solute concentrations relevant to aqueous aerosol by the rate of O3 arrival in the bulk by diffusion. As a result, bulk-phase O3 becomes depleted from its Henry's law solubility. This bulk-phase O3 depletion limits reaction timescales for relatively slow-reacting organic solutes with low interfacial affinity (i.e., trans-aconitic and maleic acids, with krxn ≈ 103-104 M-1 s-1), which is in contrast to fast-reacting solutes with higher surface affinity (i.e., nitrite, with krxn ≈ 105 M-1 s-1) where surface reactions strongly impact the observed decay kinetics.
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Affiliation(s)
- Megan D Willis
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, California 94720, United States
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19
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Zeng M, Liu CL, Wilson KR. Catalytic Coupling of Free Radical Oxidation and Electrophilic Chlorine Addition by Phase-Transfer Intermediates in Liquid Aerosols. J Phys Chem A 2022; 126:2959-2965. [PMID: 35511037 DOI: 10.1021/acs.jpca.2c00291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
While examining the heterogeneous reaction of chlorine atoms with alkenes, in the presence of Cl2, we have observed an unexpectedly large enhancement of reactivity and the predominance of chlorinated reaction products even under high O2 conditions, where Cl atom recycling is expected to be minimal. These observations cannot be explained by known free radical oxidation or cycling mechanisms, but rather we find evidence for the multiphase catalytic coupling of free radical oxidation with electrophilic Cl2 addition. The mechanism entails the production of oxygenated reaction intermediates, which act as gas-liquid phase-transfer catalysts (gl-PTCs) by promoting the accommodation of gas-phase Cl2 by the aerosol, thereby enhancing electrophilic addition. Although the majority of PTCs typically couple chemistry between two immiscible liquid phases (aqueous/organic), there are few examples of PTCs that couple gas-liquid reactions. This work shows how multiphase reaction schemes of aerosols can be reimagined for understanding catalytic reaction mechanisms.
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Affiliation(s)
- Meirong Zeng
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Chen-Lin Liu
- Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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20
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Wagner JP. 2 H-Imidazol-2-one O-Oxide: A Criegee Intermediate from a σ 0π 2 Singlet Ground-State Carbene. J Am Chem Soc 2022; 144:5937-5944. [PMID: 35325537 DOI: 10.1021/jacs.1c13705] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Triplet carbenes and triplet molecular oxygen can combine to form singlet carbonyl O-oxide Criegee intermediates in an overall spin-allowed transformation. While this reaction runs at the diffusion limit in the case of triplet carbenes, singlet carbenes are commonly more reluctant to bind 3O2. In contradiction to this customarily encountered spin selectivity, the σ0π2 singlet ground-state carbene 2H-imidazol-2-ylidene 1 reacts extremely rapidly with 3O2 at temperatures as low as 30 K. The product of this cryogenic reaction is singlet 2H-imidazol-2-one O-oxide 7, an N-heterocyclic Criegee intermediate. The addition reaction becomes possible through the electrophilic activation of dioxygen in the triplet state, in which O2 binding can initially proceed without a barrier. Criegee intermediate 7 exhibits an unprecedented high O-O stretching vibration at 1105 cm-1, which can be explained by a resonance structure with an O2 double bond. Furthermore, 2H-imidazol-2-one 5 and spiro-dioxirane 6 could be identified as the photodecomposition products of the herein-reported carbonyl oxide.
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Affiliation(s)
- J Philipp Wagner
- Institut für Organische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
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21
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Barouh N, Bourlieu-Lacanal C, Figueroa-Espinoza MC, Durand E, Villeneuve P. Tocopherols as antioxidants in lipid-based systems: The combination of chemical and physicochemical interactions determines their efficiency. Compr Rev Food Sci Food Saf 2021; 21:642-688. [PMID: 34889039 DOI: 10.1111/1541-4337.12867] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 10/22/2021] [Accepted: 10/23/2021] [Indexed: 12/20/2022]
Abstract
Lipid oxidation is a major concern in the food, cosmetic, and pharmaceutical sectors. The degradation of unsaturated lipids affects the nutritional, physicochemical, and organoleptic properties of products and can lead to off-flavors and to the formation of potentially harmful oxidation compounds. To prevent or slow down lipid oxidation, different antioxidant additives are used alone or in combination to achieve the best possible efficiency with the minimum possible quantities. In manufactured products, that is, heterogeneous systems containing lipids as emulsions or bulk phase, the efficiency of an antioxidant is determined not only by its chemical reactivity, but also by its physical properties and its interaction with other compounds present in the products. The antioxidants most widely used on the industrial scale are probably tocopherols, either as natural extracts or pure synthetic molecules. Considerable research has been conducted on their antioxidant activity, but results regarding their efficiency are contradictory. Here, we review the known mechanisms behind the antioxidant activity of tocopherols and discuss the chemical and physical features that determine their efficacy. We first describe their chemical reactivity linked with the main factors that modulate it between efficient antioxidant capacity and potential prooxidant effects. We then describe their chemical interactions with other molecules (phenolic compounds, metals, vitamin C, carotenes, proteins, and phospholipids) that have potential additive, synergistic, or antagonist effects. Finally, we discuss other physical parameters that influence their activity in complex systems including their specific interactions with surfactants in emulsions and their behavior in the presence of association colloids in bulk oils.
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Affiliation(s)
- Nathalie Barouh
- CIRAD, UMR QUALISUD, Montpellier, France.,Qualisud, Univ Montpellier, Avignon Université, CIRAD, Institut Agro, Université de La Réunion, Montpellier, France
| | | | - Maria Cruz Figueroa-Espinoza
- Qualisud, Univ Montpellier, Avignon Université, CIRAD, Institut Agro, Université de La Réunion, Montpellier, France
| | - Erwann Durand
- CIRAD, UMR QUALISUD, Montpellier, France.,Qualisud, Univ Montpellier, Avignon Université, CIRAD, Institut Agro, Université de La Réunion, Montpellier, France
| | - Pierre Villeneuve
- CIRAD, UMR QUALISUD, Montpellier, France.,Qualisud, Univ Montpellier, Avignon Université, CIRAD, Institut Agro, Université de La Réunion, Montpellier, France
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22
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Guo C, Yang M, He J, Kan G, Yu K, Liu Z, Lin S, Jiang J, Zhang H. Hypochlorous acid initiated lipid chlorination at air-water interface. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 798:149320. [PMID: 34340067 DOI: 10.1016/j.scitotenv.2021.149320] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/24/2021] [Accepted: 07/24/2021] [Indexed: 06/13/2023]
Abstract
There has been a surge of interest in interfacial hypochlorous acid (HOCl) chemistry for indoor air quality and public health. Here we combined nanoelectrospray mass spectrometry (nESI-MS) and acoustic levitation (AL) techniques to study the chlorination chemistry of three model lipids (DPPE, POPG, DOPG) mediated by HOCl at the air-water interface of levitated water droplet. For DPPE with no CC double bonds, HOCl was insensitive to the alkane chains, and showed considerable delay directing to head amino groups compared to that in aqueous environment. Chlorination chemistry, for POPG and DOPG with CC double bonds, preferentially reacted with double bonds of one chain. The mechanism was discussed in light of these observations, and it is concluded that the increased hydrophilicity of the chlorinated chain disturbed the lipid packing and attracted it toward the water phase. In addition, the reaction rate constant and reactive uptake coefficient suggested that the chlorination of lipids exposed to HOCl at the air-water interface is likely to occur rapidly. These results gain the knowledge of HOCl mediated lipid interface reaction at the molecule level, and would better understand the adverse health effects associated with elevated indoor pollutants.
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Affiliation(s)
- Changlu Guo
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, China
| | - Miao Yang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, China
| | - Jing He
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, China
| | - Guangfeng Kan
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, China
| | - Kai Yu
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, China
| | - Zhuo Liu
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, China
| | - Sifan Lin
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, China
| | - Jie Jiang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China.
| | - Hong Zhang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, China.
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23
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Yang S, Licina D, Weschler CJ, Wang N, Zannoni N, Li M, Vanhanen J, Langer S, Wargocki P, Williams J, Bekö G. Ozone Initiates Human-Derived Emission of Nanocluster Aerosols. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:14536-14545. [PMID: 34672572 DOI: 10.1021/acs.est.1c03379] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nanocluster aerosols (NCAs, particles <3 nm) are important players in driving climate feedbacks and processes that impact human health. This study reports, for the first time, NCA formation when gas-phase ozone reacts with human surfaces. In an occupied climate-controlled chamber, we detected NCA only when ozone was present. NCA emissions were dependent on clothing coverage, occupant age, air temperature, and humidity. Ozone-initiated chemistry with human skin lipids (particularly their primary surface reaction products) is the key mechanism driving NCA emissions, as evidenced by positive correlations with squalene in human skin wipe samples and known gaseous products from ozonolysis of skin lipids. Oxidation by OH radicals, autoxidation reactions, and human-emitted NH3 may also play a role in NCA formation. Such chemical processes are anticipated to generate aerosols of the smallest size (1.18-1.55 nm), whereas larger clusters result from subsequent growth of the smaller aerosols. This study shows that whenever we encounter ozone indoors, where we spend most of our lives, NCAs will be produced in the air around us.
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Affiliation(s)
- Shen Yang
- Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Dusan Licina
- Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Charles J Weschler
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Kongens Lyngby 2800, Denmark
- Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Nijing Wang
- Max Planck Institute for Chemistry, Hahn-Meitner Weg 1, Mainz 55128, Germany
| | - Nora Zannoni
- Max Planck Institute for Chemistry, Hahn-Meitner Weg 1, Mainz 55128, Germany
| | - Mengze Li
- Max Planck Institute for Chemistry, Hahn-Meitner Weg 1, Mainz 55128, Germany
| | - Joonas Vanhanen
- Airmodus Limited, Erik Palménin Aukio 1, Helsinki FI-00560, Finland
| | - Sarka Langer
- IVL Swedish Environmental Research Institute, Göteborg SE-400 14, Sweden
- Department of Architecture and Civil Engineering, Division of Building Services Engineering, Chalmers University of Technology, Göteborg SE-412 96, Sweden
| | - Pawel Wargocki
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Kongens Lyngby 2800, Denmark
| | - Jonathan Williams
- Max Planck Institute for Chemistry, Hahn-Meitner Weg 1, Mainz 55128, Germany
- Energy, Environment and Water Research Center, The Cyprus Institute, Nicosia 2121, Cyprus
| | - Gabriel Bekö
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Kongens Lyngby 2800, Denmark
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Hassan Z, Stahlberger M, Rosenbaum N, Bräse S. Criegee‐Intermediate über die Ozonolyse hinaus: Ein Einblick in Synthesen und Mechanismen. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202014974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Zahid Hassan
- Institut für Organische Chemie (IOC) Karlsruher Institut für Technologie (KIT) Fritz-Haber-Weg 6 76131 Karlsruhe Deutschland
- 3DMM2O – Exzellenzcluster (EXC-2082/1-390761711) Karlsruher Institut für Technologie (KIT) Karlsruhe Deutschland
| | - Mareen Stahlberger
- Institut für Organische Chemie (IOC) Karlsruher Institut für Technologie (KIT) Fritz-Haber-Weg 6 76131 Karlsruhe Deutschland
| | - Nicolai Rosenbaum
- Institut für Organische Chemie (IOC) Karlsruher Institut für Technologie (KIT) Fritz-Haber-Weg 6 76131 Karlsruhe Deutschland
| | - Stefan Bräse
- Institut für Organische Chemie (IOC) Karlsruher Institut für Technologie (KIT) Fritz-Haber-Weg 6 76131 Karlsruhe Deutschland
- 3DMM2O – Exzellenzcluster (EXC-2082/1-390761711) Karlsruher Institut für Technologie (KIT) Karlsruhe Deutschland
- Institut für Biologische und Chemische Systeme –, Funktionelle molekulare Systeme (IBCS-FMS) Karlsruher Institut für Technologie (KIT) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Deutschland
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25
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Hassan Z, Stahlberger M, Rosenbaum N, Bräse S. Criegee Intermediates Beyond Ozonolysis: Synthetic and Mechanistic Insights. Angew Chem Int Ed Engl 2021; 60:15138-15152. [PMID: 33283439 PMCID: PMC8359312 DOI: 10.1002/anie.202014974] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Indexed: 12/20/2022]
Abstract
After more than 70 years since their discovery, Criegee intermediates (CIs) are back at the forefront of modern chemistry of short-lived reactive intermediates. They play an important role in the mechanistic context of chemical synthesis, total synthesis, pharmaceuticals, and, most importantly, climate-controlling aerosol formation as well as atmospheric chemistry. This Minireview summarizes key aspects of CIs (from the mechanism of formation, for example, by ozonolysis of alkenes and photolysis methods employing diiodo and diazo compounds, to their electronic structures and chemical reactivity), highlights the most recent findings and some landmark results of gas-phase kinetics, and detection/measurements. The recent progress in synthetic and mechanistic studies in the chemistry of CIs provides a guide to illustrate the possibilities for further investigations in this exciting field.
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Affiliation(s)
- Zahid Hassan
- Institute of Organic ChemistryKarlsruhe Institute of TechnologyFritz-Haber-Weg 676131KarlsruheGermany
- 3DMM2O—Cluster of Excellence (EXC-2082/1–390761711)Karlsruhe Institute of Technology (KIT)76131KarlsruheGermany
| | - Mareen Stahlberger
- Institute of Organic ChemistryKarlsruhe Institute of TechnologyFritz-Haber-Weg 676131KarlsruheGermany
| | - Nicolai Rosenbaum
- Institute of Organic ChemistryKarlsruhe Institute of TechnologyFritz-Haber-Weg 676131KarlsruheGermany
| | - Stefan Bräse
- Institute of Organic ChemistryKarlsruhe Institute of TechnologyFritz-Haber-Weg 676131KarlsruheGermany
- 3DMM2O—Cluster of Excellence (EXC-2082/1–390761711)Karlsruhe Institute of Technology (KIT)76131KarlsruheGermany
- Institute of Biological and Chemical Systems (IBCS-FMS)Karlsruhe Institute of Technology (KIT)Hermann-von-Helmholtz-Platz 176344Eggenstein-LeopoldshafenGermany
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26
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Iuchi K, Takai T, Hisatomi H. Cell Death via Lipid Peroxidation and Protein Aggregation Diseases. BIOLOGY 2021; 10:399. [PMID: 34064409 PMCID: PMC8147787 DOI: 10.3390/biology10050399] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/13/2021] [Accepted: 04/29/2021] [Indexed: 12/16/2022]
Abstract
Lipid peroxidation of cellular membranes is a complicated cellular event, and it is both the cause and result of various diseases, such as ischemia-reperfusion injury, neurodegenerative diseases, and atherosclerosis. Lipid peroxidation causes non-apoptotic cell death, which is associated with cell fate determination: survival or cell death. During the radical chain reaction of lipid peroxidation, various oxidized lipid products accumulate in cells, followed by organelle dysfunction and the induction of non-apoptotic cell death. Highly reactive oxidized products from unsaturated fatty acids are detected under pathological conditions. Pathological protein aggregation is the general cause of these diseases. The cellular response to misfolded proteins is well-known as the unfolded protein response (UPR) and it is partially concomitant with the response to lipid peroxidation. Moreover, the association between protein aggregation and non-apoptotic cell death by lipid peroxidation is attracting attention. The link between lipid peroxidation and protein aggregation is a matter of concern in biomedical fields. Here, we focus on lethal protein aggregation in non-apoptotic cell death via lipid peroxidation. We reviewed the roles of protein aggregation in the initiation and execution of non-apoptotic cell death. We also considered the relationship between protein aggregation and oxidized lipid production. We provide an overview of non-apoptotic cell death with a focus on lipid peroxidation for therapeutic targeting during protein aggregation diseases.
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Affiliation(s)
- Katsuya Iuchi
- Department of Materials and Life Science, Faculty of Science and Technology, Seikei University, 3-3-1 Kichijojikitamachi, Musashino-shi, Tokyo 180-8633, Japan; (T.T.); (H.H.)
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27
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Wagner JP. Criegee Intermediates in Autoxidation Reactions: Mechanistic Considerations. J Phys Chem A 2021; 125:406-410. [PMID: 33393293 DOI: 10.1021/acs.jpca.0c09971] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Products of Criegee intermediate (CI) chemistry were recently detected in radical chain autoxidation reactions involving β-hydroxyperoxy radicals. Here, we demonstrate by means of accurate G4 computations that direct scission of the latter to CIs and radical byproducts is thermodynamically highly unfavorable. Instead, the reaction becomes possible through a hydrogen abstraction reaction that could proceed by reversible formation of a dimeric tetroxide and a subsequent [1,6] hydrogen shift of the hydroxy hydrogen.
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Affiliation(s)
- J Philipp Wagner
- Institut für Organische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
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28
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Qiu J, Tonokura K, Enami S. Proton-Catalyzed Decomposition of α-Hydroxyalkyl-Hydroperoxides in Water. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:10561-10569. [PMID: 32786584 DOI: 10.1021/acs.est.0c03438] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
In the atmosphere, most biogenic terpenes undergo ozonolysis in the presence of water to form reactive α-hydroxyalkyl-hydroperoxides (α-HHs), and the lifetimes of these α-HHs are a key parameter for understanding the processes that occur during the aging of atmospheric particles. We previously reported that α-HHs generated by ozonolysis of terpenes decompose in water to give H2O2 and the corresponding aldehydes, which undergo hydration to form gem-diols. Herein, we report that this decomposition process was dramatically accelerated by acidification of the water with oxalic, acetic, hexanoic, cis-pinonic, or hydrochloric acid. In acidic solution, the temporal profiles of the α-HHs, detected as their chloride adducts by electrospray mass spectrometry, showed single-exponential decays in the pH range from 4.1 to 6.1, and the first-order rate coefficients (k) for the decays increased with decreasing pH. The lifetime of the α-HH derived from α-terpineol was 128 min (k = (1.3 ± 0.4) × 10-4 s-1) at pH 6.1 but only 8 min (k = (2.1 ± 0.1) × 10-3 s-1) at pH 4.1. Because the rate coefficients increased as the pH decreased and the increase depended on pH rather than on the properties of the acid, we propose that the decomposition of the α-HHs in water was specifically catalyzed by H+. Fast H+-catalyzed decomposition of α-HHs could be an important source of H2O2 and multifunctionalized compounds found in ambient atmospheric particles.
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Affiliation(s)
- Junting Qiu
- Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563, Japan
| | - Kenichi Tonokura
- Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563, Japan
| | - Shinichi Enami
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan
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Zeng M, Wilson KR. Efficient Coupling of Reaction Pathways of Criegee Intermediates and Free Radicals in the Heterogeneous Ozonolysis of Alkenes. J Phys Chem Lett 2020; 11:6580-6585. [PMID: 32787230 DOI: 10.1021/acs.jpclett.0c01823] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In the gas phase, ozonolysis of olefins is known to be a significant source of free radicals. However, for heterogeneous and condensed phase ozone reactions, the importance of reaction pathways that couple Criegee intermediates (CI) with hydroxyl (OH), alkoxy, and peroxy free radicals remains uncertain. Here we report experimental evidence for substantial free radical oxidation during the heterogeneous reaction of O3 with cis-9-tricosene (Tri) aerosol. A kinetic model with three coupled submechanisms that include O3, CI, and free radical reactions is used to explain how the observed Tri reactivity and its product distributions depend upon [O3], [OH], and the presence of CI scavengers. During multiphase ozonolysis, the kinetic model predicts that only ∼30% of the alkene is actually consumed by O3, while the remaining ∼70% is consumed by free radicals that cycle through pathways involving CI. These results reveal the importance of free radical oxidation during heterogeneous ozonolysis, which has been previously difficult to isolate due to the complex coupling of CI and OH reaction pathways.
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Affiliation(s)
- Meirong Zeng
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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