9005-32-7 Usage
Description
Alginic acid is a naturally occurring polysaccharide extracted from brown seaweed genera, such as Macrocystis pyrifera. It is an acidic, insoluble white to yellowish fibrous powder that forms soluble derivatives such as sodium, potassium, and ammonium alginate, as well as propylene glycol alginate. Alginic acid and its derivatives are known for their thickening, gelling, and binding properties.
Uses
Used in Pharmaceutical Industry:
Alginic acid is used as a tablet disintegrant and as an antacid ingredient, providing relief from heartburn and indigestion.
Used in Cosmetic Industry:
Alginic acid is used in cosmetic formulations as a thickener, stabilizer, and gelling agent, derived from different varieties of brown seaweed.
Used in Food Industry:
Alginic acid and its derivatives are used to provide thickening, gelling, and binding properties in various food products such as ice cream, icings, puddings, dessert gels, and fabricated fruit. A derivative designed for improved acid and calcium stability is propylene glycol alginate. These derivatives are soluble in cold water and form non-thermoreversible gels in reaction with calcium ions and under acidic conditions.
Production Methods
Alginic acid is a hydrophilic colloid carbohydrate that occurs
naturally in the cell walls and intercellular spaces of various species
of brown seaweed (Phaeophyceae). The seaweed occurs widely
throughout the world and is harvested, crushed, and treated with
dilute alkali to extract the alginic acid.
Pharmaceutical Applications
Alginic acid is used in a variety of oral and topical pharmaceutical
formulations. In tablet and capsule formulations, alginic acid is used
as both a binder and disintegrating agent at concentrations of 1–5%
w/w. Alginic acid is widely used as a thickening and suspending
agent in a variety of pastes, creams, and gels; and as a stabilizing
agent for oil-in-water emulsions.
Alginic acid has been used to improve the stability of
levosimendan.
Therapeutically, alginic acid has been used as an antacid.In
combination with an H2-receptor antagonist, it has also been
utilized for the management of gastroesophageal reflux.
Safety Profile
Moderately toxic by intraperitoneal route. When heated to decomposition it emits acrid smoke and irritating fumes
Safety
Alginic acid is widely used in food products and topical and oral
pharmaceutical formulations. It is generally regarded as a nontoxic
and nonirritant material, although excessive oral consumption may
be harmful. Inhalation of alginate dust may be an irritant and has
been associated with industrially related asthma in workers
involved in alginate production. However, it appears that the cases
of asthma were linked to exposure to unprocessed seaweed dust
rather than pure alginate dust. An acceptable daily intake of
alginic acid and its ammonium, calcium, potassium, and sodium
salts was not set by the WHO because the quantities used, and the
background levels in food, did not represent a hazard to health.
LD50 (rat, IP): 1.6 g/kg
storage
Alginic acid hydrolyzes slowly at warm temperatures producing a
material with a lower molecular weight and lower dispersion
viscosity.
Alginic acid dispersions are susceptible to microbial spoilage on
storage, which may result in some depolymerization and hence a
decrease in viscosity. Dispersions should therefore be preserved with
an antimicrobial preservative such as benzoic acid; potassium
sorbate; sodium benzoate; sorbic acid; or paraben. Concentrations
of 0.1–0.2% are usually used.
Alginic acid dispersions may be sterilized by autoclaving or
filtration through a 0.22 μm filter. Autoclaving may result in a
decrease in viscosity which can vary depending upon the nature of
any other substances present.
Alginic acid should be stored in a well-closed container in a cool,
dry place.
Purification Methods
To 5g of acid in 550mL water containing 2.8g KHCO3 are added 0.3mL of acetic acid and 5g potassium acetate. EtOH is added to make the solution to 25% (v/v) in EtOH, and any insoluble material is discarded. Further addition of EtOH, to 37% (v/v), precipitated alginic acid. Collect the acid and dry it in vacuo. [Pal & Schubert J Am Chem Soc 84 4384 1962.]
Incompatibilities
Incompatible with strong oxidizing agents; alginic acid forms
insoluble salts in the presence of alkaline earth metals and group III
metals with the exception of magnesium.
Regulatory Status
GRAS listed. Accepted in Europe for use as a food additive.
Included in the FDA Inactive Ingredients Database (ophthalmic
preparations, oral capsules, and tablets). Included in the Canadian
List of Acceptable Non-medicinal Ingredients. Included in nonparenteral
medicines licensed in the UK.
Check Digit Verification of cas no
The CAS Registry Mumber 9005-32-7 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 9,0,0 and 5 respectively; the second part has 2 digits, 3 and 2 respectively.
Calculate Digit Verification of CAS Registry Number 9005-32:
(6*9)+(5*0)+(4*0)+(3*5)+(2*3)+(1*2)=77
77 % 10 = 7
So 9005-32-7 is a valid CAS Registry Number.
InChI:InChI=1/C14H22O13/c1-23-7-3(15)6(18)14(27-9(7)11(19)20)25-8-4(16)5(17)13(24-2)26-10(8)12(21)22/h3-10,13-18H,1-2H3,(H,19,20)(H,21,22)
9005-32-7Relevant articles and documents
Two competing reactions of tetrabutylammonium alginate in organic solvents: Amidation versus γ-lactone synthesis
Schleeh, Thomas,Madau, Mathieu,Roessner, Dierk
, p. 53 - 60 (2016)
Biocompatibility and thickening properties predetermine alginates as ingredients in food, cosmetic and pharmaceutical products. Further chemical modifications are often desired for a product optimization. The introduction of hydrophobic groups can be realized by employing organic tetrabutylammonium alginate (TBA-Alg) solutions. The synthesis of alginic acid alkyl amides from TBA-Alg with 2-chloro-1-methylpyridinium iodide (CMPI) as a coupling agent, however, has so far not resulted in a high degree of amidation. The analysis of the coupling reaction revealed the formation of mannuronic acid γ-lactone structures, which required a conformation change from 1C4 to 4C1. The opening of the γ-lactone required a high excess of butylamine. In the case of CMPI, triethylamine had to be added prior to the coupling agent in order to suppress the assumed alginic acid formation. The degrees of amidation achieved were up to 0.8, and for propylphosphonic anhydride as the coupling agent up to 1. The molecular weights of the alginic acid butyl amide were ≥35 kDa.