1.Role of carbonyls and aromatics in the formation of tropospheric ozone in Rio de Janeiro, Brazil.
da Silva DB1, Martins EM1, Corrêa SM2. Environ Monit Assess. 2016 May;188(5):289. doi: 10.1007/s10661-016-5278-3. Epub 2016 Apr 14.
The ozone in Rio de Janeiro has been in violation of national air quality standards. Among all of the monitoring stations, the Bangu neighbourhood has the most violations of the national standard of 160 μg m(-3) for the years 2012 and 2013. This study evaluated the reactivity of the carbonyls and aromatics in the tropospheric ozone formation processes. The samples were collected between July and October of 2013. Carbonyls were sampled using SiO2 cartridges coated with C18 and impregnated with 2,4-dinitrophenylhydrazine and were analysed by HPLC. Activated carbon cartridges and GC/MS were used to measure the concentration of monoaromatic hydrocarbons. An air quality monitoring station provided the concentrations of the criteria pollutants and the meteorological parameters. Cluster analysis and a Pearson correlation matrix were used to determine the formation of groups and the correlation of the variables. The evaluation of the volatile organic compounds (VOC) reaction with OH radicals and the MIR scale was used to extrapolate the reactivity of VOCs to the ozone formation.
2.Application of AlkBGT and AlkL from Pseudomonas putida GPo1 for selective alkyl ester ω-oxyfunctionalization in Escherichia coli.
van Nuland YM1, Eggink G2, Weusthuis RA3. Appl Environ Microbiol. 2016 Apr 15. pii: AEM.00822-16. [Epub ahead of print]
The enzyme system AlkBGT fromPseudomonas putidaGPo1 can efficiently ω-functionalize fatty acid methyl esters. Outer membrane protein AlkL boosts this ω-functionalization. In this study it is shown that whole-cells ofE. coliexpressing the AlkBGT system can also ω-oxidize ethyl nonanoate (NAEE). Co-expression of AlkBGT and AlkL resulted in 1.7-fold higher ω-oxidation activity on NAEE. With this strain, initial activity on NAEE was 70 U/gcdw, 67% of the initial activity on methyl nonanoate. In time-lapse conversions with 5 mM NAEE the main product was 9-hydroxy NAEE (3.6 mM), but also 9-oxo NAEE (0.1 mM) and 9-carboxy NAEE (0.6 mM) were formed. AlkBGT also ω-oxidized ethyl, propyl and butyl esters of fatty acids ranging from C6 to C10. Increasing the length of the alkyl chain improved the ω-oxidation activity of AlkBGT on esters of C6 and C7 fatty acids. From these esters, application of butyl hexanoate resulted in the highest ω-oxidation activity of 82 U/gcdw Co-expression of AlkL only had a positive effect on ω-functionalization of substrates with a total length of C11 or longer.
3.Influence of solvents on the composition of condensed tannins in grape pomace seed extracts.
Bosso A1, Guaita M2, Petrozziello M2. Food Chem. 2016 Sep 15;207:162-9. doi: 10.1016/j.foodchem.2016.03.084. Epub 2016 Mar 25.
The extracting effectiveness of some solvents (water, ethanol, acetone, ethyl acetate), used as pure or in binary and ternary mixtures, was studied for the extraction of seeds from the fermented pomace of Nebbiolo cv. The aqueous mixtures of acetone provided the highest extraction yields in total polyphenols and total flavonoids. Polyphenolic extracts were also obtained with aqueous mixtures of ethanol or acetone at variable concentrations, and the condensed tannins were quantified with the phloroglucinolysis method. The aqueous mixtures of acetone were more effective than the corresponding aqueous mixtures of ethanol. The solvent influenced the extraction yield and the composition of the extracts: with the increase of the yield, the mean degree of polymerization (mDP) of the condensed tannins increased. A significant correlation was noticed between mDP and the molar percentages of (+)-catechin as terminal unit (negative correlation), and of (-)-epicatechin and (-)-epicatechin-3O-gallate as extension units (positive correlation).
4.Design and synthesis of some novel 4-Chloro-N-(4-(1-(2-(2-cyanoacetyl)hydrazono)ethyl)phenyl) benzenesulfonamide derivatives as anticancer and radiosensitizing agents.
Ghorab MM1, Ragab FA2, Heiba HI3, Soliman AM3. Eur J Med Chem. 2016 Apr 6;117:8-18. doi: 10.1016/j.ejmech.2016.04.009. [Epub ahead of print]
A novel series of sulfonamide derivatives 4-21 have been synthesized starting from the strategic starting material (E)-4-Chloro-N-(4-(1-(2-(2-cyanoacetyl)hydrazono)ethyl)phenyl) benzenesulfonamide 4. Two series of hydrazone 5-9, and pyridone 10-21 derivatives bearing a sulfonamide moiety were obtained. All the newly synthesized compounds were evaluated for their in vitro cytotoxic activity against human liver cancer cell line (HepG2). Compounds 4-6, 8, 9, 10-14 and 16-18 showed higher activity compared to doxorubicin as a positive control. The radiosensitizing ability of the most promising compounds 4, 10 and 12 was studied which showed an increase in the cell killing effect of γ-radiation after combination with these derivatives. The molecular design was performed to predict the binding mode of the most promising compounds 4, 10 and 12 with the active site of hCA IX, that showed appropriate fitting with the relevant amino acids in the binding pocket on the basis of standard bond lengths, angles, S score and E conformation data.