Showing posts with label Alkaline Hydrolysis. Show all posts
Showing posts with label Alkaline Hydrolysis. Show all posts

Thursday, 28 April 2022

Humic Acids Aggregates as Microheterogeneous Reaction Media: Alkaline Hydrolysis Reactions

 Compounds 2022, 2(2), 131-143


The influence of humic aggregates in a water solution upon the chemical stability under basic conditions of different substrates was reviewed. The kinetic behavior of each substrate was modeled in terms of a micellar pseudophase model.

Monday, 22 February 2016

A widely used spectrophotometric assay to quantify olive oil biophenols according to the health claim (EU Reg. 432/2012)

European Journal of Lipid Science and Technology
DOI: 10.1002/ejlt.201500313


The purpose of this work was to find a simple, cheap, and suitable method, among the most widely employed, able to guarantee a proper determination and quantification of the phenolic content of extra virgin olive oils (EVOOs), in order to satisfy the requirements of the specific health claim (EU Reg. 432/2012). Total phenolic content by Folin–Ciocalteu (FC) was used and compared versus phenolic profile by HPLC-UV, considering this latter as the most sensitive and specific method for evaluating the phenolic content. Both protocols were performed before and after an acid hydrolysis of the polar phenolic fraction that involves a break of the bound forms of hydroxytyrosol (HTyr) and tyrosol (Tyr), with a simplification of the phenolic profile, and quantification of their total free forms. Results of the phenolic compounds of twelve EVOOs, determined by the different analytical approaches, were statistically compared by means of two-tailed paired t-tests: data obtained by the FC assay (expressed as HTyr) before and/or after acid hydrolysis were statistically comparable with results obtained by acid hydrolysis-HPLC (as sum of HTyr and Tyr).

Monday, 27 April 2015

Cleavage of carbofuran and carbofuran-derivatives in micellar aggregates

Progress in Reaction Kinetics and Mechanism, 40 (2015) 105-118




In recent years, the stability of carbamate pesticides have been studied by our research group in a wide range of biomimetic microheterogeneous media such as micelles or reverse micelles. These microheterogeneous media included different surfactant species and, hence, different self-assembled structures. In particular, basic hydrolysis of carbofuran and its derivatives have been analysed in the presence of anionic, cationic, non-ionic and reverse micelles. The results obtained from these physicochemical and kinetic studies, as well as a consistent comparison of them, are now summarised.

Monday, 23 February 2015

Alkaline hydrolysis of vinclozolin: effect of humic acids aggregates in water


Journal of Molecular Catalysis A: Chemical


The influence of natural organic substances as humate colloidal aggregates in water solutions upon the chemical stability of vinclozolin has been investigated in basic media. A large inhibition (9 times-fold) has been observed and it has been rationalized in terms of a micellar pseudophase model. The observed behaviour could increase significantly the half-life of this fungicide. Moreover, these experimental results have been compared with the corresponding ones of other substances in these natural colloidal aggregates.