scholarly journals Synthesis, Structure, and Properties of a Mixed-Valent Triiron Complex of Tetramethyl Reductic Acid, an Ascorbic Acid Analogue, and Its Relationship to a Functional Non-Heme Iron Oxidation Catalyst System

2007 ◽  
Vol 46 (15) ◽  
pp. 6099-6107 ◽  
Author(s):  
YooJin Kim ◽  
Xudong Feng ◽  
Stephen J. Lippard
Keyword(s):  
Ascorbic Acid ◽  
Iron Oxidation ◽  
Catalyst System ◽  
Heme Iron ◽  
Oxidation Catalyst ◽  
Structure And Properties ◽  
Non Heme Iron ◽  
Acid Analogue

Determining the Fate of a Non-Heme Iron Oxidation Catalyst Under Illumination, Oxygen, and Acid

2016 ◽  
Vol 55 (21) ◽  
pp. 11040-11049 ◽  
Author(s):  
Samuel L. Esarey ◽  
Joel C. Holland ◽  
Bart M. Bartlett
Keyword(s):  
Iron Oxidation ◽  
Heme Iron ◽  
Oxidation Catalyst ◽  
Non Heme Iron

scholarly journals New Sensor to Measure the Microencapsulated Active Compounds Released in an Aqueous Liquid Media Based in Dielectric Properties in Radiofrequency Range

Sensors ◽  
2021 ◽  
Vol 21 (17) ◽  
pp. 5781
Author(s):  
Juan Angel Tomas-Egea ◽  
Pedro J. Fito ◽  
Ricardo J. Colom ◽  
Marta Castro-Giraldez
Keyword(s):  
Ascorbic Acid ◽  
Dielectric Properties ◽  
Chemical Species ◽  
Alginate Beads ◽  
Heme Iron ◽  
Nutritional Disorder ◽  
Active Compounds ◽  
Non Heme Iron ◽  
Acid Environment ◽  
Impedance Sensor

In recent years, the general and scientific interest in nutrition, digestion, and what role they play in our body has increased, and there is still much work to be carried out in the field of developing sensors and techniques that are capable of identifying and quantifying the chemical species involved in these processes. Iron deficiency is the most common and widespread nutritional disorder that mainly affects the health of children and women. Iron from the diet may be available as heme or organic iron, or as non-heme or inorganic iron. The absorption of non-heme iron requires its solubilization and reduction in the ferric state to ferrous that begins in the gastric acid environment, because iron in the ferric state is very poorly absorbable. There are chemical species with reducing capacity (antioxidants) that also have the ability to reduce iron, such as ascorbic acid. This paper aims to develop a sensor for measuring the release of encapsulated active compounds, in different media, based on dielectric properties measurement in the radio frequency range. An impedance sensor able to measure the release of microencapsulated active compounds was developed. The sensor was tested with calcium alginate beads encapsulating iron ions and ascorbic acid as active compounds. The prediction and measurement potential of this sensor was improved by developing a thermodynamic model that allows obtaining kinetic parameters that will allow suitable encapsulation design for subsequent release.

scholarly journals FORTIFIKASI GUAVA (Psidium guajava L.) JELLY DRINK DENGAN ZAT BESI ORGANIK DARI KEDELAI (Glycine max L.) DAN KACANG HIJAU (Vigna radiate L.)

2017 ◽  
Vol 11 (1) ◽  
pp. 10
Author(s):  
Christina Hanny Setyaningrum ◽  
Ivone Elizabeth Fernandez ◽  
Robertus Probo Yulianto Nugrahedi
Keyword(s):  
Ascorbic Acid ◽  
Iron Content ◽  
Extraction Process ◽  
Psidium Guajava ◽  
Heme Iron ◽  
The Body ◽  
Deficiency Anemia ◽  
Non Heme Iron ◽  
Glycine Max L ◽  
Nutrition Value

Anemia is a condition of haemoglobin level that is below normal. One of the major causes is lacking of iron consumption, which is important in haemoposis process. Compared to men, women have less total iron in the body, and it raises the risk of anemia. The main purpose of this research was the fortification of iron in beverage. This research used soybean and mungbean as source of iron, which known as non-heme iron. To improve the absorption, ascorbic acid was needed as an enhancer, using guava and was produced into guava jelly drink. Method for extraction process is by maseration with 30% etanol as solution. The value of iron extract assessed by AAS at 248,3 nm. The formula of fortification was 20% of RDA of iron for woman, which was 18 mg per day. Chosen product was evaluated by sensory test. The nutrition value of product assessed including iron content, ascorbic acid, and proximate composition. The iron content of soybean was 113,86 ppm and 58,76 for mungbean. The nutrition of guava jelly drink with addition of fortificant were 87,47% water, 0,35% ash, 0,2% fat, 0,31% protein, 11,67% carbohydrate, 130,48 ppm iron, and 90,79 mg ascorbic acid. Keywords: iron deficiency anemia, soy bean, mungbean, jelly drink, and guava

scholarly journals Deuterated N2Py2 Ligands: Building More Robust Non-Heme Iron Oxidation Catalysts

ACS Catalysis ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 3564-3575 ◽  
Author(s):  
Jianming Chen ◽  
Robertus J. M. Klein Gebbink
Keyword(s):  
Iron Oxidation ◽  
Heme Iron ◽  
Oxidation Catalysts ◽  
Non Heme Iron

Strongly Coupled Redox-Linked Conformational Switching at the Active Site of the Non-Heme Iron-Dependent Dioxygenase, TauD

2019 ◽  
Author(s):  
Christopher John ◽  
Greg M. Swain ◽  
Robert P. Hausinger ◽  
Denis A. Proshlyakov
Keyword(s):  
Active Site ◽  
Structural Model ◽  
Heme Iron ◽  
Chemical Transformations ◽  
Experimental Conditions ◽  
Strongly Coupled ◽  
Non Heme Iron ◽  
Reversible Redox ◽  
Wide Range ◽  
Complex Structural

2-Oxoglutarate (2OG)-dependent dioxygenases catalyze C-H activation while performing a wide range of chemical transformations. In contrast to their heme analogues, non-heme iron centers afford greater structural flexibility with important implications for their diverse catalytic mechanisms. We characterize an <i>in situ</i> structural model of the putative transient ferric intermediate of 2OG:taurine dioxygenase (TauD) by using a combination of spectroelectrochemical and semi-empirical computational methods, demonstrating that the Fe (III/II) transition involves a substantial, fully reversible, redox-linked conformational change at the active site. This rearrangement alters the apparent redox potential of the active site between -127 mV for reduction of the ferric state and 171 mV for oxidation of the ferrous state of the 2OG-Fe-TauD complex. Structural perturbations exhibit limited sensitivity to mediator concentrations and potential pulse duration. Similar changes were observed in the Fe-TauD and taurine-2OG-Fe-TauD complexes, thus attributing the reorganization to the protein moiety rather than the cosubstrates. Redox difference infrared spectra indicate a reorganization of the protein backbone in addition to the involvement of carboxylate and histidine ligands. Quantitative modeling of the transient redox response using two alternative reaction schemes across a variety of experimental conditions strongly supports the proposal for intrinsic protein reorganization as the origin of the experimental observations.

Sign in / Sign up

Export Citation Format

Share Document