Preparation of D-Galacturonic Acid from Pectin^*

Abstract

NOTESVol. 65 oxide (0.15 g.) rapidly took up one cquivalent of hydrogen.The product boiled at 166-16.9" at 19 mm., and crystallized on cooling; m. p. 69-70".Anal. Calcd. for CISH180: C, 82.0; H, 9.5. Found: C, 82.0; H, 9.2. 4-Amino-2-cyclohexyl-5-methylphenol.-A cold suspension of cyclohexylcresol (5.7 9.) in aqueous sodium hydroxide was mixed with a solution prepared by diazotizing 6.3 g. of sulfanilic acid. Bfter it had stood for one hour, the mixture was treated with a solution of 14 g. of sodium hydrosulfite and then warmed until reduction was complete. The product was removed by filtration and crystallized from benzene. I t formed colorless nodules (4.8 g. 7851;) that became pink at 170" and melted to a browri liquid at 182".

Salts of galacturonic acid and their application to the preparation of galacturonic acid from pectic substances

“…Although crystallization from aqueous solution is convenient for large quantities, crystallization from aqueous alcohol, or aqueous acetic acid, is preferable for small quantities, because there is less loss in handling the material. 7. STRONTIUM GALACTURONATE, Sr(CGHg07)2.5H20…”

Preparation of salts of galacturonic acid from beet pulp

“…It was known that Pectinol causes complete hydrolysis of pectic acid [4] and of soluble pectins [11], but it was not known whether it would attack: the protopectin in the cell walls of the beet root.…”

Preparation of sodium strontium galacturonate from citrus products

“…7 The solution was filtered to remove the strontium sulfate, and was then concentrated to a volume of 900 ml in a vacuum still at a temperature of 40° C. The strontium sulfate that separated during the evaporation was removed by filtration, and the residue on the filter was washed with 100 ml of hot water. The clear filtrate was seeded with crystalline galacturonic acid hydrate and was allowed to cool to room temperature with constant stirring.…”

“…Mottern and Cole [6] improved the process by employing a commercial pectic enzyme for the hydrolysis of pectic acid, and Rietz and Maclay [7] showed that the method was also applicable to the preparation of galacturonic acid from pectin. In the preparation of sodium strontium galacturonate reported here, pectic acid is the most convenient raw material for laboratory use, and the most economical at the present price of the commercial enzyme.…”