89-65-6 Usage
Chemical Properties
Erythorbic acid occurs as a white or slightly yellow-colored crystals
or powder. It gradually darkens in color upon exposure to light.
Uses
Different sources of media describe the Uses of 89-65-6 differently. You can refer to the following data:
1. Antioxidant (industrial and food), especially in
brewing industry, reducing agent in photography.
2. Erythorbic Acid is a food preservative that is a strong reducing agent (oxygen accepting) which functions similarly to antioxidants. In the dry crystalline state it is nonreactive, but in water solutions it reacts readily with atmospheric oxygen and other oxidizing agents, making it valuable as an antioxidant. During preparation, dissolving and mixing should incorporate a minimum amount of air, and storage should be at cool temperatures. It has a solubility of 43 g/100 ml of water at 25°c. One part is equivalent to one part ascorbic acid and equivalent to one part sodium erythorbate. It is used to control oxidative color and flavor deterioration in fruits at 150–200 ppm. It is used in meat curing to speed and control the nitrite curing reaction and prolong the color of cured meat at levels of 0.05%.
3. Erythorbic Acid is used as a food additive as an antimicrobial and antioxidative agent.
Production Methods
Erythorbic acid is synthesized by the reaction between methyl 2-
keto-D-gluconate and sodium methoxide. It can also be synthesized
from sucrose, and produced from Penicillium spp.
Biotechnological Production
Yeasts and other fungi synthesize the C5 sugar acid D-erythroascorbic acid which
shares structural and physicochemical properties with Asc. D-erythroascorbic
acid serves similar protective functions in these microorganisms as Asc does in plants
and animals, including the scavenging of reactive oxygen species. The biosynthesis
of D-erythroascorbic acid starts from D-arabinose obtained by the microorganism
from decaying plant material. D-arabinose, presumably in its
1,4-furanosidic isomeric form, is oxidized by NAD(P)+ specific dehydrogenases
to D-arabinono-1,4-lactone, which is further oxidized to D-erythroascorbic
acid by D-arabinono-1,4-lactone oxidase. Resting cells of Saccharomyces
cerevisiae can synthesize Asc from L-galactose, L-galactono-1,4-lactone, or L-gulono-
1,4-lactone via the pathway naturally used for D-erythroascorbic acid.
Flammability and Explosibility
Nonflammable
Pharmaceutical Applications
Erythorbic acid is a stereoisomer of L-ascorbic acid, and is used as
an antioxidant in foods and oral pharmaceutical formulations. It
has approximately 5% of the vitamin C activity of L-ascorbic acid.
Safety
Erythorbic acid is widely used in food applications as an
antioxidant. It is also used in oral pharmaceutical applications as
an antioxidant. Erythorbic acid is generally regarded as nontoxic
and nonirritant when used as an excipient. Erythorbic acid is readily
metabolized and does not affect the urinary excretion of ascorbic
acid.
The WHO has set an acceptable daily intake of erythorbic acid
and its sodium salt in foods at up to 5 mg/kg body-weight.
storage
Erythorbic acid should be stored in an airtight container, protected
from light, in a cool, dry place.
Purification Methods
Crystallise D(-)-isoascorbic acid from H2O, EtOH or dioxane. is at 245nm with 7,500 (EtOH). [Reichstein et al. Helv max Chim Acta 17 510, 516 1934, Heslop et al. J Chem Soc 225 1944, Beilstein 18 III/IV 3037, 18/5 V 26.]
Incompatibilities
Erythorbic acid is incompatible with chemically active metals such
as aluminum, copper, magnesium, and zinc. It is also incompatible
with strong bases and strong oxidizing agents.
Regulatory Status
GRAS listed. Accepted for use as a food additive in Europe.
Included in the FDA Inactive Ingredients Database (oral concentrate
and tablets).
Check Digit Verification of cas no
The CAS Registry Mumber 89-65-6 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 8 and 9 respectively; the second part has 2 digits, 6 and 5 respectively.
Calculate Digit Verification of CAS Registry Number 89-65:
(4*8)+(3*9)+(2*6)+(1*5)=76
76 % 10 = 6
So 89-65-6 is a valid CAS Registry Number.
InChI:InChI=1/C7H10O6/c1-7(3(9)2-8)5(11)4(10)6(12)13-7/h3,8-11H,2H2,1H3/t3?,7-/m1/s1
89-65-6Relevant articles and documents
Oxidation reactions of thymol: A pulse radiolysis and theoretical study
Venu,Naik,Sarkar,Aravind, Usha K.,Nijamudheen,Aravindakumar
, p. 291 - 299 (2013/03/14)
The reactions of ?OH and O?-, with thymol, a monoterpene phenol and an antioxidant, were studied by pulse radiolysis technique and DFT calculations at B3LYP/6-31+G(d,p) level of theory. Thymol was found to efficiently scavenge OH radicals (k = 8.1 × 109 dm3 mol-1 s-1) to produce reducing adduct radicals, with an absorption maximum at 330 nm and oxidizing phenoxyl radicals, with absorption maxima at 390 and 410 nm. A major part of these adduct radicals was found to undergo water elimination, leading to phenoxyl radicals, and the process was catalyzed by OH- (or Na2HPO4). The rate of reaction of O?- with thymol was found to be comparatively low (k = 1.1 × 109 dm3 mol -1 s-1), producing H abstracted species of thymol as well as phenoxyl radicals. Further, these phenoxyl radicals of thymol were found to be repaired by ascorbate (k = 2.1 × 108 dm3 mol -1 s-1). To support the interpretation of the experimental results, DFT calculations were carried out. The transients (both adducts and H abstracted species) have been optimized in gas phase at B3LYP/6-31+G(d,p) level of calculation. The relative energy values and thermodynamic stability suggests that the ortho adduct (C6-OH adduct) to be most stable in the reaction of thymol with OH radicals, which favors the water elimination. However, theoretical calculations showed that C4 atom in thymol (para position) can also be the reaction center as it is the main contributor of HOMO. The absorption maxima (λmax) calculated from time-dependent density functional theory (TDDFT) for these transient species were close to those obtained experimentally. Finally, the redox potential value of thymol?/ thymol couple (0.98 V vs NHE) obtained by cyclic voltammetry is less than those of physiologically important oxidants, which reveals the antioxidant capacity of thymol, by scavenging these oxidants. The repair of the phenoxyl radicals of thymol with ascorbate together with the redox potential value makes it a potent antioxidant with minimum pro-oxidant effects.
Outer-Sphere Electron-Transfer Reactions of Ascorbate Anions
Williams, Nicola H.,Yandell, John K.
, p. 1133 - 1144 (2007/10/02)
Rate constants for the one-electron oxidation of ascorbate dianion (A2-) by bis(terpyridine)cobalt(III) ion (8.5*106 dm3 mol-1 s-1) and pentaammine(pyridine)ruthenium(III) ion (6.0*109 dm3 mol-1 s-1), and of the monoanion (HA-) by tetraammine(bipyridine)ruthenium(III) ion (2.1*105 dm3 mol-1 s-1) have been determined in aqueous solution at 25 deg C and ionic strength 0.1 (NaNO3 or NaClO4).It is shown that these rate constants, and other published rate constants for oxidation of HA- and A2-, are consistent with the Marcus cross relation, on the assumption that the self-exchange rate constants for both the HA-/HA. and A2-/A-. couples are 106 dm3 mol-1 s-1.One-electron redox potentials for the ascorbate/dehydroascorbate system have been derived from scattered literature data.
