Fe(III)-Citrate-Complex-Induced Photooxidation of 3-Methylphenol in Aqueous Solution

The photodegradation process of m-cresol (3-methylphenol), induced by Fe(III)-Cit complex, was investigated upon irradiation at 365 nm in natural water. The composition and photochemical properties of Fe(III)-Cit complex were studied by UV-Visible absorption spectrophotometer for optimizing the stoichiometry of the complex and photolysis under irradiation at 365 nm, respectively. A dark investigation of the system was performed before studying the photochemical behavior. The photooxidation efficiencies of m-cresol were dependent on the pH value, optimized at pH 2.86, oxygen, initial concentrations of Fe(III)-Cit complex, and m-cresol. Additionally, to look into the mechanism of m-cresol degradation using Fe(III)-Cit, tertiobutanol alcohol was used as scavenger for hydroxyl radicals and the result suggested that hydroxyl radical attack was the main pathway of m-cresol degradation. Besides, oxygen can enhance the photolysis of Fe(III)-Citrate complex by trapping the electron on the carbon centered radical formed after the photoredox process. Then O •− 2 formed reacts rapidly leading finally to formation of • OH radical. In absence of oxygen, less reactive species are formed; consequently the disappearance of m-cresol was strongly inhibited. Our work shows that the presence of Fe(III)-Citrate complex could have a considerable impact on the fate of organic pollutant in aquatic environment

Fe(III)-Citrate-Complex-Induced Photooxidation of 3-Methylphenol in Aqueous Solution

The photodegradation process of m-cresol (3-methylphenol), induced by Fe(III)-Cit complex, was investigated upon irradiation at 365 nm in natural water. The composition and photochemical properties of Fe(III)-Cit complex were studied by UV-Visible absorption spectrophotometer for optimizing the stoichiometry of the complex and photolysis under irradiation at 365 nm, respectively. A dark investigation of the system was performed before studying the photochemical behavior. The photooxidation efficiencies of m-cresol were dependent on the pH value, optimized at pH 2.86, oxygen, initial concentrations of Fe(III)-Cit complex, and m-cresol. Additionally, to look into the mechanism of m-cresol degradation using Fe(III)-Cit, tertiobutanol alcohol was used as scavenger for hydroxyl radicals and the result suggested that hydroxyl radical attack was the main pathway of m-cresol degradation. Besides, oxygen can enhance the photolysis of Fe(III)-Citrate complex by trapping the electron on the carbon centered radical formed after the photoredox process. Then O2•− formed reacts rapidly leading finally to formation of •OH radical. In absence of oxygen, less reactive species are formed; consequently the disappearance of m-cresol was strongly inhibited. Our work shows that the presence of Fe(III)-Citrate complex could have a considerable impact on the fate of organic pollutant in aquatic environment

How does extrusion chage the phenolic profileand impact protein digestibility in sorghum flours?

In this work, the effect of thermoplastic extrusion on the phenolic compounds (PC)profile by UPLC-MSEand on the solubility/polymerization of kafirins by SE-HPLC was evaluated in extruded whole sorghum, with or withouttannins. Free (FPC) and bound (BPC)phenolic compoundswere extracted separately.The characteristics evaluated are antioxidant activity (by the methods DPPH and FRAP),total phenoliccontent(by the methodology involving the Reagent of Folin Ciocalteu), total proanthocyanidinscontent (TPAC) and total flavonoid content (TFC). FPC and BPC ranged from 41.1 to 434.3and 8.2to 283.7mg GAE/100g (db), respectively.DPPH and FRAP analysis showed a strong correlation with TPC (0.99and 0.95, p< 0.05, respectively). TPAC and TFC showthe degradation of tannins in monomeric flavonoids, after extrusion. Globally, 58 FPC and 100 BPC were tentatively identified. PCA biplotindicated a clear distinction between PC profile in flour and extrudate in both genotypes. SE-HPLC showed an increase in protein solubility after extrusion thus it also improves protein digestibility.This work reveals that the extrusion improve the release of BPC, the breakdown of polyphenols and the depolymerization of kafirinsin sorghum grains, promoting theuse of this cereal as a potential functional foodfor humans.CBCP; 5 a 9 out