Procédé de traitement de produits biologiques « Extraction par Pressage Préservant l’Intégrité du... more Procédé de traitement de produits biologiques « Extraction par Pressage Préservant l’Intégrité du Produit (EPPIP) » en vue de la modification de leur contenu lipidique et de leur texture; mise en oeuvre d’un tel procédé et reconstitution par des méthodes préservant l’apparence des graines et leurs qualités organoleptiques.
The current healthy life style pushed to develop and implement a novel efficient defatting proces... more The current healthy life style pushed to develop and implement a novel efficient defatting process of high quality called "Mechanical Expression Preserving Shape Integrity" that conserved the sensory, color, textural, morphological and acceptability of partially defatted roasted peanuts. In this study, Response Surface Methodology was used to investigate the best extraction parameters (initial water content, pressure and pressing duration) based on the highest Color Consumer Evaluation scores, the best colorimetric parameters (L*, a*, b*, ΔE*) and the most appealing textural attributes (Fracturability, First Fracture Work Done, First Fracture Percentage of Deformation, Rupture Force, Percentage of Deformation at Rupture). Experimental results showed that defatting promotes a lighter and neutral grain color, higher fracturability and rupture force as well as higher deformation strength. Aiming to retain most of the colorimetric and textural properties after defatting and roasting, it was found that peanuts should be hydrated to 7 % d.b. and treated at 4.74 MPa for 14.22 min.
The main purpose of this study was to extract the maximum amount of oil from peanuts without caus... more The main purpose of this study was to extract the maximum amount of oil from peanuts without causing major damage and preserving their organoleptic quality after defatting. Accordingly, a successful, healthy, eco-friendly and economic defatting process for peanuts was implemented using mechanical oil expression, which was optimized by means of Response Surface Methodology. The results demonstrated that maximum extraction yields were obtained at a low initial moisture content (5-7% d.b.). Defatting and deformation ratios were mostly affected by the pressure and water content with high correlation coefficients (98.4% and 97.5%, respectively), and overall acceptability decreased following higher oil extraction yields. It was concluded that the optimum values for the product moisture content, pressure, and pressing duration were 5% d.b., 9.7MPa and 4min, respectively, with a defatting ratio of 70.6%. This resulted in an insignificant irreversible deformation ratio (<1%) and an overall acceptability of 7.6 over 10.
International Conference on Renewable Energies for Developing Countries 2014, 2014
ABSTRACT This article represents a scientific approach to the environment-friendly and energy sav... more ABSTRACT This article represents a scientific approach to the environment-friendly and energy saving processes which incited us to develop a new efficient, healthy, economical and less polluting defatting process. In this paper, mechanical oil extraction was conducted on peanuts by preserving their structure integrity and the process was followed by a quantitative and qualitative study on the physicochemical properties of the defatted grains in order to investigate the best extraction parameters. The described extraction process coupled to a reconstitution process by Intensification of Vaporization by Decompression to the Vacuum (IVDV) showed that the optimal conditions are 5% d.b. initial water content, 2 days at 4°C of homogenization period, pressing at around 10 MPa (at room temperature) for 3 to 4 min most preferably at a compression speed of 8mm/sec, using the appropriate process modification to avoid structure damages and loss of deteriorated seeds, then reconstituting by IVDV with a pressure of 0.9MPa applied for 10 sec on hydrated peanuts to 10% d.b.
The photolysis of HONO has been found to be the oxidation driver through OH formation in the indo... more The photolysis of HONO has been found to be the oxidation driver through OH formation in the indoor air measurement campaign SURFin, an extensive campaign carried out in July 2012 in a classroom in Marseille. In the present study, the INCA-Indoor model is used to evaluate different HONO formation mechanisms that have been used previously in indoor air quality models. In order to avoid biases in the results due to the uncertainty in rate constants, those parameters were adjusted to fit one representative day of the SURFin campaign. Then, the mechanisms have been tested with the optimized parameters against other experiments carried out during the SURFin campaign. Based on the observations and these findings, we propose a new mechanism incorporating sorption of NO2 onto surfaces with possible saturation of these surfaces. This mechanism is able to better reproduce the experimental profiles over a large range of conditions. This article is protected by copyright. All rights reserved.
Proceedings of the National Academy of Sciences, 2013
The hydroxyl (OH) radical is the most important oxidant in the atmosphere since it controls its s... more The hydroxyl (OH) radical is the most important oxidant in the atmosphere since it controls its self-oxidizing capacity. The main sources of OH radicals are the photolysis of ozone and the photolysis of nitrous acid (HONO). Due to the attenuation of solar radiation in the indoor environment, the possibility of OH formation through photolytic pathways indoors has been ignored up to now. In the indoor air, the ozonolysis of alkenes has been suggested as an alternative route of OH formation. Models and indirect measurements performed up to now according to this hypothesis suggest concentrations of OH radicals on the order of 10(4)-10(5) molecules per cubic centimeter. Here, we present direct measurements of significant amounts of OH radicals of up to 1.8⋅10(6) molecules per cubic centimeter during an experimental campaign carried out in a school classroom in Marseille. This concentration is on the same order of magnitude of outdoor OH levels in the urban scenario. We also show that photolysis of HONO is an important source of OH radicals indoors under certain conditions (i.e., direct solar irradiation inside the room). Additionally, the OH concentrations were found to follow a linear dependence with the product J(HONO)⋅[HONO]. This was also supported by using a simple quasiphotostationary state model on the OH radical budget. These findings force a change in our understanding of indoor air quality because the reactivity linked to OH would involve formation of secondary species through chemical reactions that are potentially more hazardous than the primary pollutants in the indoor air.
Environmental Science and Pollution Research, 2017
Health risks posed by ambient air pollutants to the urban Lebanese population have not been well ... more Health risks posed by ambient air pollutants to the urban Lebanese population have not been well characterized. The aim of this study is to assess cancer risk and mortality burden of non-methane hydrocarbons (NMHCs) and particulates (PM) based on two field-sampling campaigns conducted during summer and winter seasons in Beirut. Seventy NMHCs were analyzed by TD-GC-FID. PM2.5 elemental carbon (EC) components were examined using a Lab OC-EC aerosol Analyzer, and polycyclic aromatic hydrocarbons were analyzed by GC-MS. The US EPA fraction-based approach was used to assess non-cancer hazard and cancer risk for the hydrocarbon mixture, and the UK Committee on Medical Effects of Air Pollutants (COMEAP) guidelines were followed to determine the PM2.5 attributable mortality burden. The average cumulative cancer risk exceeded the US EPA acceptable level (10(-6)) by 40-fold in the summer and 30-fold in the winter. Benzene was found to be the highest contributor to cancer risk (39-43%), followed by 1,3-butadiene (25-29%), both originating from traffic gasoline evaporation and combustion. The EC attributable average mortality fraction was 7.8-10%, while the average attributable number of deaths (AD) and years of life lost (YLL) were found to be 257-327 and 3086-3923, respectively. Our findings provide a baseline for future air monitoring programs, and for interventions aiming at reducing cancer risk in this population.
International Conference on Renewable Energies For Developing Countries 2014, Nov 26, 2014
ABSTRACT This article represents a scientific approach to the environment-friendly and energy sav... more ABSTRACT This article represents a scientific approach to the environment-friendly and energy saving processes which incited us to develop a new efficient, healthy, economical and less polluting defatting process. In this paper, mechanical oil extraction was conducted on peanuts by preserving their structure integrity and the process was followed by a quantitative and qualitative study on the physicochemical properties of the defatted grains in order to investigate the best extraction parameters. The described extraction process coupled to a reconstitution process by Intensification of Vaporization by Decompression to the Vacuum (IVDV) showed that the optimal conditions are 5% d.b. initial water content, 2 days at 4°C of homogenization period, pressing at around 10 MPa (at room temperature) for 3 to 4 min most preferably at a compression speed of 8mm/sec, using the appropriate process modification to avoid structure damages and loss of deteriorated seeds, then reconstituting by IVDV with a pressure of 0.9MPa applied for 10 sec on hydrated peanuts to 10% d.b.
NitroMAC (French acronym for continuous atmospheric measurements of nitrogenous compounds) is an ... more NitroMAC (French acronym for continuous atmospheric measurements of nitrogenous compounds) is an instrument which has been developed for the semi-continuous measurement of atmospheric nitrous acid (HONO). This instrument relies on wet chemical sampling and detection using high performance liquid chromatography (HPLC)-visible absorption at 540nm. Sampling proceeds by dissolution of gaseous HONO in a phosphate buffer solution followed by derivatization with sulfanilamide/N-(1-naphthyl)-ethylenediamine. The performance of this instrument was found to be as follows: a detection limit of around 3ppt with measurement uncertainty of 10% over an analysis time of 10min. Intercomparison was made between the instrument and a long-path absorption photometer (LOPAP) during two experiments in different environments. First, air was sampled in a smog chamber with concentrations up to 18ppb of nitrous acid. NitroMAC and LOPAP measurements showed very good agreement. Then, in a second experiment, ambient air with HONO concentrations below 250ppt was sampled. While NitroMAC showed its capability of measuring HONO in moderate and highly polluted environments, the intercomparison results in ambient air highlighted that corrections must be made for minor interferences when low concentrations are measured.
ABSTRACT We measured HONO concentrations during a winter field campaign in a suburban site. We co... more ABSTRACT We measured HONO concentrations during a winter field campaign in a suburban site. We compared calculations with measurements and found missing source of HONO. Much higher HONO missing source is found when snow was present at ground. This evidences the existence of a large HONO formation in presence of snow. These findings may significantly affect the photochemistry in urban winter atmosphere. a b s t r a c t Nitrous acid measurements were carried out during the MEGAPOLI (Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation) winter field campaign at the SIRTA observatory in Paris surroundings from the 20th of January to the 15th of February 2010. At the end of the campaign, significant snow events occurred leading to snow accumulation at the sampling site during the last days. These specific conditions gave the opportunity to examine the HONO budget with and without the presence of snow at ground. Much higher HONO sources were found for the days when the site was covered by snow. This provides evidence for the existence of a large snowpack source of HONO in mid-latitude polluted regions that needs to be investigated for a better understanding of wintertime photochemistry.
Environmental context Non-methane hydrocarbons play an important role in the formation of photoch... more Environmental context Non-methane hydrocarbons play an important role in the formation of photochemical oxidants such as ozone. We investigate factors controlling the distribution of non-methane hydrocarbons in an urban area of the Middle East. The study highlights the importance of local emissions and atmospheric dynamics, and the limited effect of photochemistry at the measurement site. Measurements of over 70 C2-C16 non-methane hydrocarbons (NMHCs) were conducted in suburban Beirut (1.3 million inhabitants) in summer 2011 and winter 2012 during the Emission and Chemistry of Organic Carbon in the East Mediterranean (ECOCEM) field campaign. The levels of NMHCs observed exceeded by a factor of two in total volume the levels found in northern mid-latitude megacities (Paris and Los Angeles), especially for the unburned fossil fuel fraction. Regardless of the season, the major compounds, explaining 50% of the concentrations, were toluene, isopentane, butane, m,p-xylenes, propane and et...
Measurements of gaseous and particulate organic carbon were performed during the MEGAPOLI experim... more Measurements of gaseous and particulate organic carbon were performed during the MEGAPOLI experiments, in July 2009 and January–February 2010, at the SIRTA observatory in suburban Paris. Measurements comprise primary and secondary volatile organic compounds (VOCs), of both anthropogenic and biogenic origins, including C<sub>12</sub>–C<sub>16</sub> <i>n</i>-alkanes of intermediate volatility (IVOCs), suspected to be efficient precursors of secondary organic aerosol (SOA). The time series of gaseous carbon are generally consistent with times series of particulate organic carbon at regional scale, and are clearly affected by meteorology and air mass origin. Concentration levels of anthropogenic VOCs in urban and suburban Paris were surprisingly low (2–963 ppt) compared to other megacities worldwide and to rural continental sites. Urban enhancement ratios of anthropogenic VOC pairs agree well between the urban and suburban Paris sites, showing the reg...
This work optimized the β-cyclodextrin (β-CD)-assisted extraction process of polyphenols from vin... more This work optimized the β-cyclodextrin (β-CD)-assisted extraction process of polyphenols from vine shoots. The efficiency of β-CD was compared to that of ethanol in terms of the quantity and antioxidant capacity (AC) of the extracted polyphenols. Response surface methodology permitted the optimization of the β-CD concentration, time, and temperature. The optimal polyphenol content (PC) [5.8 mg of gallic acid equivalent (GAE)/g of dry matter (DM)] and AC [3146 micromolar trolox equivalent per milliliter (μMTE)] were initially obtained with Syrah cultivar after an extraction of 48 h at 66.6 °C with a 37.7 mg/mL aqueous β-CD solvent. The same PC (5.8 mg of GAE/g of DM) was reached with 50% ethanol/water solvent after 1.65 h. However, a lower AC was found with ethanol (2000 μMTE) compared to β-CD. A comparison of the PC and AC of four different vine shoot cultivars was realized. Our results clearly show the capacity of β-CD to amplify polyphenol extraction from vine shoots.
Procédé de traitement de produits biologiques « Extraction par Pressage Préservant l’Intégrité du... more Procédé de traitement de produits biologiques « Extraction par Pressage Préservant l’Intégrité du Produit (EPPIP) » en vue de la modification de leur contenu lipidique et de leur texture; mise en oeuvre d’un tel procédé et reconstitution par des méthodes préservant l’apparence des graines et leurs qualités organoleptiques.
The current healthy life style pushed to develop and implement a novel efficient defatting proces... more The current healthy life style pushed to develop and implement a novel efficient defatting process of high quality called &amp;amp;amp;amp;amp;amp;quot;Mechanical Expression Preserving Shape Integrity&amp;amp;amp;amp;amp;amp;quot; that conserved the sensory, color, textural, morphological and acceptability of partially defatted roasted peanuts. In this study, Response Surface Methodology was used to investigate the best extraction parameters (initial water content, pressure and pressing duration) based on the highest Color Consumer Evaluation scores, the best colorimetric parameters (L*, a*, b*, ΔE*) and the most appealing textural attributes (Fracturability, First Fracture Work Done, First Fracture Percentage of Deformation, Rupture Force, Percentage of Deformation at Rupture). Experimental results showed that defatting promotes a lighter and neutral grain color, higher fracturability and rupture force as well as higher deformation strength. Aiming to retain most of the colorimetric and textural properties after defatting and roasting, it was found that peanuts should be hydrated to 7 % d.b. and treated at 4.74 MPa for 14.22 min.
The main purpose of this study was to extract the maximum amount of oil from peanuts without caus... more The main purpose of this study was to extract the maximum amount of oil from peanuts without causing major damage and preserving their organoleptic quality after defatting. Accordingly, a successful, healthy, eco-friendly and economic defatting process for peanuts was implemented using mechanical oil expression, which was optimized by means of Response Surface Methodology. The results demonstrated that maximum extraction yields were obtained at a low initial moisture content (5-7% d.b.). Defatting and deformation ratios were mostly affected by the pressure and water content with high correlation coefficients (98.4% and 97.5%, respectively), and overall acceptability decreased following higher oil extraction yields. It was concluded that the optimum values for the product moisture content, pressure, and pressing duration were 5% d.b., 9.7MPa and 4min, respectively, with a defatting ratio of 70.6%. This resulted in an insignificant irreversible deformation ratio (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;1%) and an overall acceptability of 7.6 over 10.
International Conference on Renewable Energies for Developing Countries 2014, 2014
ABSTRACT This article represents a scientific approach to the environment-friendly and energy sav... more ABSTRACT This article represents a scientific approach to the environment-friendly and energy saving processes which incited us to develop a new efficient, healthy, economical and less polluting defatting process. In this paper, mechanical oil extraction was conducted on peanuts by preserving their structure integrity and the process was followed by a quantitative and qualitative study on the physicochemical properties of the defatted grains in order to investigate the best extraction parameters. The described extraction process coupled to a reconstitution process by Intensification of Vaporization by Decompression to the Vacuum (IVDV) showed that the optimal conditions are 5% d.b. initial water content, 2 days at 4°C of homogenization period, pressing at around 10 MPa (at room temperature) for 3 to 4 min most preferably at a compression speed of 8mm/sec, using the appropriate process modification to avoid structure damages and loss of deteriorated seeds, then reconstituting by IVDV with a pressure of 0.9MPa applied for 10 sec on hydrated peanuts to 10% d.b.
The photolysis of HONO has been found to be the oxidation driver through OH formation in the indo... more The photolysis of HONO has been found to be the oxidation driver through OH formation in the indoor air measurement campaign SURFin, an extensive campaign carried out in July 2012 in a classroom in Marseille. In the present study, the INCA-Indoor model is used to evaluate different HONO formation mechanisms that have been used previously in indoor air quality models. In order to avoid biases in the results due to the uncertainty in rate constants, those parameters were adjusted to fit one representative day of the SURFin campaign. Then, the mechanisms have been tested with the optimized parameters against other experiments carried out during the SURFin campaign. Based on the observations and these findings, we propose a new mechanism incorporating sorption of NO2 onto surfaces with possible saturation of these surfaces. This mechanism is able to better reproduce the experimental profiles over a large range of conditions. This article is protected by copyright. All rights reserved.
Proceedings of the National Academy of Sciences, 2013
The hydroxyl (OH) radical is the most important oxidant in the atmosphere since it controls its s... more The hydroxyl (OH) radical is the most important oxidant in the atmosphere since it controls its self-oxidizing capacity. The main sources of OH radicals are the photolysis of ozone and the photolysis of nitrous acid (HONO). Due to the attenuation of solar radiation in the indoor environment, the possibility of OH formation through photolytic pathways indoors has been ignored up to now. In the indoor air, the ozonolysis of alkenes has been suggested as an alternative route of OH formation. Models and indirect measurements performed up to now according to this hypothesis suggest concentrations of OH radicals on the order of 10(4)-10(5) molecules per cubic centimeter. Here, we present direct measurements of significant amounts of OH radicals of up to 1.8⋅10(6) molecules per cubic centimeter during an experimental campaign carried out in a school classroom in Marseille. This concentration is on the same order of magnitude of outdoor OH levels in the urban scenario. We also show that photolysis of HONO is an important source of OH radicals indoors under certain conditions (i.e., direct solar irradiation inside the room). Additionally, the OH concentrations were found to follow a linear dependence with the product J(HONO)⋅[HONO]. This was also supported by using a simple quasiphotostationary state model on the OH radical budget. These findings force a change in our understanding of indoor air quality because the reactivity linked to OH would involve formation of secondary species through chemical reactions that are potentially more hazardous than the primary pollutants in the indoor air.
Environmental Science and Pollution Research, 2017
Health risks posed by ambient air pollutants to the urban Lebanese population have not been well ... more Health risks posed by ambient air pollutants to the urban Lebanese population have not been well characterized. The aim of this study is to assess cancer risk and mortality burden of non-methane hydrocarbons (NMHCs) and particulates (PM) based on two field-sampling campaigns conducted during summer and winter seasons in Beirut. Seventy NMHCs were analyzed by TD-GC-FID. PM2.5 elemental carbon (EC) components were examined using a Lab OC-EC aerosol Analyzer, and polycyclic aromatic hydrocarbons were analyzed by GC-MS. The US EPA fraction-based approach was used to assess non-cancer hazard and cancer risk for the hydrocarbon mixture, and the UK Committee on Medical Effects of Air Pollutants (COMEAP) guidelines were followed to determine the PM2.5 attributable mortality burden. The average cumulative cancer risk exceeded the US EPA acceptable level (10(-6)) by 40-fold in the summer and 30-fold in the winter. Benzene was found to be the highest contributor to cancer risk (39-43%), followed by 1,3-butadiene (25-29%), both originating from traffic gasoline evaporation and combustion. The EC attributable average mortality fraction was 7.8-10%, while the average attributable number of deaths (AD) and years of life lost (YLL) were found to be 257-327 and 3086-3923, respectively. Our findings provide a baseline for future air monitoring programs, and for interventions aiming at reducing cancer risk in this population.
International Conference on Renewable Energies For Developing Countries 2014, Nov 26, 2014
ABSTRACT This article represents a scientific approach to the environment-friendly and energy sav... more ABSTRACT This article represents a scientific approach to the environment-friendly and energy saving processes which incited us to develop a new efficient, healthy, economical and less polluting defatting process. In this paper, mechanical oil extraction was conducted on peanuts by preserving their structure integrity and the process was followed by a quantitative and qualitative study on the physicochemical properties of the defatted grains in order to investigate the best extraction parameters. The described extraction process coupled to a reconstitution process by Intensification of Vaporization by Decompression to the Vacuum (IVDV) showed that the optimal conditions are 5% d.b. initial water content, 2 days at 4°C of homogenization period, pressing at around 10 MPa (at room temperature) for 3 to 4 min most preferably at a compression speed of 8mm/sec, using the appropriate process modification to avoid structure damages and loss of deteriorated seeds, then reconstituting by IVDV with a pressure of 0.9MPa applied for 10 sec on hydrated peanuts to 10% d.b.
NitroMAC (French acronym for continuous atmospheric measurements of nitrogenous compounds) is an ... more NitroMAC (French acronym for continuous atmospheric measurements of nitrogenous compounds) is an instrument which has been developed for the semi-continuous measurement of atmospheric nitrous acid (HONO). This instrument relies on wet chemical sampling and detection using high performance liquid chromatography (HPLC)-visible absorption at 540nm. Sampling proceeds by dissolution of gaseous HONO in a phosphate buffer solution followed by derivatization with sulfanilamide/N-(1-naphthyl)-ethylenediamine. The performance of this instrument was found to be as follows: a detection limit of around 3ppt with measurement uncertainty of 10% over an analysis time of 10min. Intercomparison was made between the instrument and a long-path absorption photometer (LOPAP) during two experiments in different environments. First, air was sampled in a smog chamber with concentrations up to 18ppb of nitrous acid. NitroMAC and LOPAP measurements showed very good agreement. Then, in a second experiment, ambient air with HONO concentrations below 250ppt was sampled. While NitroMAC showed its capability of measuring HONO in moderate and highly polluted environments, the intercomparison results in ambient air highlighted that corrections must be made for minor interferences when low concentrations are measured.
ABSTRACT We measured HONO concentrations during a winter field campaign in a suburban site. We co... more ABSTRACT We measured HONO concentrations during a winter field campaign in a suburban site. We compared calculations with measurements and found missing source of HONO. Much higher HONO missing source is found when snow was present at ground. This evidences the existence of a large HONO formation in presence of snow. These findings may significantly affect the photochemistry in urban winter atmosphere. a b s t r a c t Nitrous acid measurements were carried out during the MEGAPOLI (Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation) winter field campaign at the SIRTA observatory in Paris surroundings from the 20th of January to the 15th of February 2010. At the end of the campaign, significant snow events occurred leading to snow accumulation at the sampling site during the last days. These specific conditions gave the opportunity to examine the HONO budget with and without the presence of snow at ground. Much higher HONO sources were found for the days when the site was covered by snow. This provides evidence for the existence of a large snowpack source of HONO in mid-latitude polluted regions that needs to be investigated for a better understanding of wintertime photochemistry.
Environmental context Non-methane hydrocarbons play an important role in the formation of photoch... more Environmental context Non-methane hydrocarbons play an important role in the formation of photochemical oxidants such as ozone. We investigate factors controlling the distribution of non-methane hydrocarbons in an urban area of the Middle East. The study highlights the importance of local emissions and atmospheric dynamics, and the limited effect of photochemistry at the measurement site. Measurements of over 70 C2-C16 non-methane hydrocarbons (NMHCs) were conducted in suburban Beirut (1.3 million inhabitants) in summer 2011 and winter 2012 during the Emission and Chemistry of Organic Carbon in the East Mediterranean (ECOCEM) field campaign. The levels of NMHCs observed exceeded by a factor of two in total volume the levels found in northern mid-latitude megacities (Paris and Los Angeles), especially for the unburned fossil fuel fraction. Regardless of the season, the major compounds, explaining 50% of the concentrations, were toluene, isopentane, butane, m,p-xylenes, propane and et...
Measurements of gaseous and particulate organic carbon were performed during the MEGAPOLI experim... more Measurements of gaseous and particulate organic carbon were performed during the MEGAPOLI experiments, in July 2009 and January–February 2010, at the SIRTA observatory in suburban Paris. Measurements comprise primary and secondary volatile organic compounds (VOCs), of both anthropogenic and biogenic origins, including C<sub>12</sub>–C<sub>16</sub> <i>n</i>-alkanes of intermediate volatility (IVOCs), suspected to be efficient precursors of secondary organic aerosol (SOA). The time series of gaseous carbon are generally consistent with times series of particulate organic carbon at regional scale, and are clearly affected by meteorology and air mass origin. Concentration levels of anthropogenic VOCs in urban and suburban Paris were surprisingly low (2–963 ppt) compared to other megacities worldwide and to rural continental sites. Urban enhancement ratios of anthropogenic VOC pairs agree well between the urban and suburban Paris sites, showing the reg...
This work optimized the β-cyclodextrin (β-CD)-assisted extraction process of polyphenols from vin... more This work optimized the β-cyclodextrin (β-CD)-assisted extraction process of polyphenols from vine shoots. The efficiency of β-CD was compared to that of ethanol in terms of the quantity and antioxidant capacity (AC) of the extracted polyphenols. Response surface methodology permitted the optimization of the β-CD concentration, time, and temperature. The optimal polyphenol content (PC) [5.8 mg of gallic acid equivalent (GAE)/g of dry matter (DM)] and AC [3146 micromolar trolox equivalent per milliliter (μMTE)] were initially obtained with Syrah cultivar after an extraction of 48 h at 66.6 °C with a 37.7 mg/mL aqueous β-CD solvent. The same PC (5.8 mg of GAE/g of DM) was reached with 50% ethanol/water solvent after 1.65 h. However, a lower AC was found with ethanol (2000 μMTE) compared to β-CD. A comparison of the PC and AC of four different vine shoot cultivars was realized. Our results clearly show the capacity of β-CD to amplify polyphenol extraction from vine shoots.
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