Oral administration of β-galactosidase, which alleviate lactose intolerance symptoms, is challenging due to its instability throughout the gastrointestinal tract. The objective of this work was to make correlations between the in-vitro digestion and chemical characteristics of a β-galactosidase/carboxymethylchitosan-silica biocatalyst powder. This was obtained by a one-pot silica gel route assisted by carboxymethyl chitosan, using maltose as lyoprotectant.
View Article and Find Full Text PDFSea-salt aerosols (SSA) are one of the key natural aerosols in our atmosphere, consisting predominantly of sodium chloride (NaCl). Throughout their atmospheric transport, these aerosols undergo complex internal mixing, giving rise to a rich variety of inorganic and organic species, including dicarboxylic acids. This study investigates firstly the composition and deliquescence properties of coarse particles containing pure malonic acid (MA, CH(COOH)) and internally mixed NaCl and MA, by means of an acoustic levitation system coupled with a Raman microspectrometer.
View Article and Find Full Text PDFOzone exacerbates allergy symptoms to certain pollens. The molecular mechanisms by which ozone affects pollen grains (PGs) and allergies are not fully understood, especially as the effects of pollutants may vary depending on the type of pollen. In this work, pollens of 22 different taxa were exposed under laboratory conditions to ozone (100 ppb) to quantify the ozone uptake by the PGs.
View Article and Find Full Text PDFFormaldehyde (HCHO) is one of the abundant indoor pollutants and has been classified as a human carcinogen by the International Agency for Research on Cancer (IARC). Indoor HCHO at schools is particularly important due to the high occupancy density and the health effects on children. In this study, high time resolved measurement of formaldehyde concentration was conducted in the classrooms at elementary school, high school and university under normal students' activities in three different locations in the Region Centre Val de Loire-France.
View Article and Find Full Text PDFSodium chloride (NaCl) is the main constituent of sea-salt aerosols. During atmospheric transport, sea-salt aerosols can interact with gases and other particles including secondary aerosols containing ammonium sulfate ((NH4)2SO4). This paper reports on the deliquescence relative humidity (DRH) of internally mixed sodium chloride-ammonium sulfate (NaCl/(NH4)2SO4) coarse particles by means of an acoustic levitation system fitted with a confocal Raman microscope (CRM).
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