Algin acetate

Ester Formation - propylene glyeol alginate, acetate and sulfate esters of alginate... 

Alginic acid [9005-32-7] M 48,000-186000. To 5g in 550mL water containing 2.8g KHCO3, were added 0.3mL acetic acid and 5g potassium acetate. EtOH to make the soln 25% (v/v) in EtOH was added and any insoluble material was discarded. Further addition of EtOH, to 37% (v/v), ppted alginic acid. [Pal and Schubert J Am Chem Soc 84 4384 1962.]... 

In fermentation for the production of acetic acid, ethyl alcohol is used in an aerobic process. In an ethanol oxidation process, the biocatalyst Acetobacter aceti was used to convert ethanol to acetic acid under aerobic conditions. A continuous fermentation for vinegar production was proposed for utilisation of non-viable A. aceti immobilised on the surface of alginate beads. 

Flavor emulsions are similarly stabilized by the viscosity produced upon addition of a vegetable gum, such as tragacanth, Irish moss extract, arabic, a cellulose gum, or one of the alginates, to the aqueous phase. Here the oil phase, in the form of the flavor, is in small proportion to the water. In the absence of the acetic acid, contained in the vinegar of the French dressing. 

Chitosan is insoluble at alkaline and neutral pH values but it can form salts with inorganic and organic acids such as hydrochloric acid, lactic add, acetic add and glutamic acid. In contrast to alginates and carrageenans in solution, the amino fundions of chitosan are protonated and the resultant soluble polysaccharide is... 

The selective dense layer of hydrophilic membranes is made from different polymers with a high affinity for water. These polymers contain ions, oxygen functions like hydroxyl, ester, ether or carboxylic moieties, or nitrogen as imino or imi-do groups. Preferred hydropilic polymers are polyvinylalcohol (PVA) [32], poly-imides, cellulose acetate (CA) or natural polymers like chitosan [33] or alginates. Organophilic membranes usually consist of crosslinked silicones, mostly polydimethyl siloxane (PDMS) or polymethyl octyl siloxane (POMS). 

Immobilisation of an Acetobacter aceti strain in calcium alginate resulted in improvement of the operational stability, substrate tolerance and specific activity of the cells and 23 g phenylacetic acid was produced within 9 days of fed-batch cultivation in an airlift bioreactor [133]. Lyophilised mycelia of Aspergillus oryzae and Rhizopus oryzae have been shown to efficiently catalyse ester formation with phenylacetic acid and phenylpropanoic acid and different short-chain alkanols in organic solvent media owing to their carboxylesterase activities [134, 135] (Scheme 23.8). For instance, in n-heptane with 35 mM acid and 70 mM alcohol, the formation of ethyl acetate and propylphenyl acetate was less effective (60 and 65% conversion yield) than if alcohols with increased chain lengths were used (1-butanol 85%, 3-methyl-l-butanol 86%, 1-pentanol 91%, 1-hexanol 100%). This effect was explained by a higher chemical affinity of the longer-chain alcohols, which are more hydrophobic, to the solvent. 

Polysorbates or sorbitan esters, acacia, and tragacanth Aluminum magnesium silicate, bentonite, carbomers, cellulose derivatives, gelatin, pectin, polyvinyl alcohol, alginates, starch, and xanthan gum Borates, citrates, acetates, and phosphates... 

Nondegradable polymers are also useful as matrices for ocular implants. This application requires the polymer to be hydrophilic, to minimize local tissue irritation. Need for ocular implants stems from the challenges posed to conventional ocular medicines (i.e., eye drops) such as rapid dilution, tear washout, poor patient compliance, and limited bioavailability. Ocular implants from hydrophilic polymer matrices that provide localized sustained release may overcome the above limitations. The first polymeric sustained release product to reach the market was Ocusert , a pilocarpin sustained release ocular implant developed by Alza. Ocusert has the drug reservoir as a thin disc of pilocarpine-alginate complex sandwiched between two transparent discs of microporous membrane fabricated from ethylene-vinyl acetate copolymer. The microporous membranes permit the tear fluid to penetrate into the drug reservoir compartment to dissolve pilocarpine from the complex. Pilocarpine molecules are then released at a constant rate of 20 or 40 pg/hr for a four- to seven-day management of glaucoma. 

Pheniramine Acetate (Naphcon A) Nepafenac (Nevanac) Olopatadine (Patanol) GASTROINTESTINAL Antacids Alginic Acid +... 

U.S. Toti, M.Y. Kariduraganavar, K.S. Soppimath, T.M. Aminabhavi, Sorption, diffusion and pervaporation separation of water/acetic acid mixtures through the blend membranes of sodium alginate and guar gum-g-poly(acrylamide), J. Appl. Polym. Sci. 83 (2002) 259-272. 

X.P. Wang, Modified alginate composite membranes for the dehydration of acetic acid, J. Membr. Sci. 170 (2000) 71-79. 

As an example of hybridization of zeolites with cellulose derivatives, self-supporting zeolite membranes with a sponge-like architecture and zeolite microtubes were prepared by using CA filter membranes as a template [154]. The hierarchical structure with sub-nanometer- to micrometer-sized pores is a characteristic of great promise for a wide range of applications such as catalysis, adsorption, and separation. There was also an attempt to prepare alginate membranes incorporated with zeolites, e.g., for pervaporation separation of water/acetic acid mixtures [155]. 

Acetic acid Glyoxylic scid Oxalic acid L-Alanine L-Glutamine L-Histidine Alginate Bacterial cellulose Curdlan... 

Ammoniacal Silver Nitrate TS, 850 Ammonia Detector Tube, 862 Ammoniated Glycyrrhizin, 23 Ammonia TS, 850 Ammonia TS, Stronger, 850 Ammonia Water, Stronger, 850 Ammonium Acetate TS, 850 Ammonium Alginate, 24 Ammonium Alum, 20 Ammonium Bicarbonate, 25 Ammonium Carbonate, 25 Ammonium Carbonate TS, 850... 

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