Identifying Citric Acid Esters, a Class of Phthalate Substitute Plasticizers, in Indoor Dust via an Integrated Target, Suspect, and Characteristic Fragment-Dependent Screening Strategy

2021 ◽  
Author(s):  
Yayun Zhang ◽  
Jianhua Li ◽  
Guanyong Su
Keyword(s):  
Citric Acid ◽  
Screening Strategy ◽  
Indoor Dust ◽  
Characteristic Fragment ◽  
Acid Esters

In vitro digestion of citric acid esters of mono- and diglycerides (CITREM) and CITREM-containing infant formula/emulsions

2014 ◽  
Vol 5 (7) ◽  
pp. 1409-1421 ◽  
Author(s):  
Sawsan Amara ◽  
Amaury Patin ◽  
Francesca Giuffrida ◽  
Tim J. Wooster ◽  
Sagar K. Thakkar ◽  
...  
Keyword(s):  
Citric Acid ◽  
Infant Formula ◽  
In Vitro Digestion ◽  
First Time ◽  
Digestive Lipases ◽  
Acid Esters

The GI lipolysis of CITREM is investigated for the first time using various digestive lipases and a two-stepin vitrodigestion model.

scholarly journals Applying target data screening followed by characteristic fragment filtering for the comprehensive screening and identification of alkaloids in Corydalis yanhusuo W. T. Wang by UPLC-Q-TOF/MSE

RSC Advances ◽  
2017 ◽  
Vol 7 (84) ◽  
pp. 53545-53551 ◽  
Author(s):  
Meiling Wang ◽  
Yuehong Liu ◽  
Shuang Fu ◽  
Qingqing Zhang ◽  
Qing Wang ◽  
...  
Keyword(s):  
Screening Strategy ◽  
Screening And Identification ◽  
Characteristic Fragment ◽  
Data Screening ◽  
Target Data ◽  
Tof Ms

A target data screening strategy followed by characteristic fragment filtering by UPLC-Q-TOF/MSE was developed for rapidly and comprehensively identifying alkaloids in Corydalis yanhusuo W. T. Wang (Yanhusuo).

scholarly journals IDENTIFICATION AND QUANTITATIVE DETERMINATION OF ESTERS OF CITRIC ACID

2019 ◽  
Vol 62 (10) ◽  
pp. 110-117
Author(s):  
Svetlana V. Sushkova ◽  
Svetlana V. Levanova ◽  
Il’ya L. Glazko
Keyword(s):  
Citric Acid ◽  
Raw Materials ◽  
Complex Mixture ◽  
Internal Standard ◽  
Structural Features ◽  
Reaction Mass ◽  
Polar Phase ◽  
Internal Standard Method ◽  
Synthesis Conditions ◽  
Acid Esters

The necessity and possibility of creating a domestic technology for the production of citric acid esters - trialkyl citrates - effective and environmentally friendly plasticizing compositions based on renewable raw materials are substantiated. Trialkylcitrates a purity of 98-99% are obtained by azeotropic esterification of citric acid with aliphatic alcohols C4-C5 under conditions of homogeneous acid catalysis. Using the synthesis of triamyl citrate as an example, the esterification of a polybasic hydroxy acid has been considered. It was established that during the synthesis a complex mixture is formed consisting of unreacted citric acid, incomplete mono-, diesters and triamyl citrate. The influence of synthesis conditions (temperature, reagent ratio, catalyst amount and reaction time) on the composition of the reaction mass is shown. A method of gas chromatographic analysis of citric acid esters has been developed. Taking into account the structural features of citric acid and its partial esters containing polar carboxyl groups, the reaction mass was pre-methylated with synthesized diazomethane. The resulting mixture consists of six esters of citric acid: trimethylcitrate; 2-hydroxy-1,3-dicarboxymethyl-2-carboxyamylpropane; 2-hydroxy-1,2-dicarboxymethyl-3-carboxyamil propane; 2-hydroxy-1-carboxymethyl-2,3-dicarboxysamyl propane; 2-hydroxy-2-carboxymethyl-1,3-dicarboxyamyl propane; triamylcitrate. The analysis was performed on a chromatographic complex "Crystal-2000M" on a capillary column with a grafted non-polar phase OV-101, length 100 m. The analysis time ranged from 22 to 49.5 min. Empirical equations were obtained using the internal standard method (the standard is dicyclohexyl adipate) to determine the calibration coefficients of the starting (trimethyl citrate т citric acid) and final (triamyl citrate) products in a wide concentration range. The results of identification of structures of six esters of citric acid for which there is no information in existing databases are presented. The study was carried out by method of chromato-mass spectrometry on the instrument SHIMADZU GCMS – QP2010 with ionization by electron impact at ionization energy of 130 eV. The analysis of the obtained spectra made it possible to determine the most probable ways of fragmentation of organic molecules and the intensity of the peaks of the ions formed.

scholarly journals The Role of Emulsifiers on the Crystallization of Cocoa Butter and Cocoa Butter-sugar Blends

2021 ◽  
Author(s):  
Selvyn Simoes
Keyword(s):  
Citric Acid ◽  
Cocoa Butter ◽  
Crystallization Kinetics ◽  
Isothermal Crystallization ◽  
Castor Oil ◽  
Nucleation And Growth ◽  
Soy Lecithin ◽  
Polyglycerol Polyricinoleate ◽  
Acid Esters

The crystallization of cocoa butter and 1:1 cocoa butter-sugar blends containing 2 wt% emulsifier was investigated. The emulsifiers studied were soy lecithin, polyglycerol polyricinoleate (PGPR), citric acid esters of mono- and diglycerides (CITREM) and ammonium phosphatides (YN). Lecithin, CITREM and YN enhanced nucleation and growth events substantially, however, had minimal effects on the form IV-to-V transition and enthalpy. PGPR showed a modest enhancement of crystallization kinetics but promoted the formation of form V polymorph similar to that of canola and castor oil. In the presence of sugar, emulsifiers were no longer able to influence nucleation and growth. Sugar also hindered the form IV-to-V transition in the presence of both emulsifier and oil. Overall, results showed that emulsifiers may be used to tune the isothermal crystallization of cocoa butter, though this depends on the presence of dispersed sugar.

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