Potassium Phosphate, Dibasic → HCID 23689150, compound

Temperature

30 °C

For microbial oxidation of D-xylose or L-arabinose, fermentation medium (1 L) contains K2HPO4 (2 g), KH2PO4 (1 g), (NH4)2SO4 (5 g) and yeast extract (5 g). Solutions of D-xylose (100 g) or L-arabinose (100 g) and MgSO4 (0.24 g) are autoclaved separately and added immediately prior to initiation of the fermentation. Inoculants are started by introduction of a Pseudomonas fragi single colony picked from a nutrient agar plate into 5 mL of fermentation medium. Cultures are grown at 30° C. with agitation at 250 rpm until they are turbid (˜24 h) and subsequently transferred to 100 mL of fermentation medium. Cultures are grown at 30° C. and 250 rpm for an additional 12 h. The inoculant (OD600=1.0-3.0) is then transferred into the fermentation vessel and the batch fermentation is initiated (t=0 h). The fermentation control settings are: 30° C., stirring speed at 650 rpm, and airflow at 0.5 L/L/min. The culture medium is maintained at pH 6.4 by addition of 2 N H2SO4 and a base solution, which is 30% CaCO3 for oxidation of D-xylose or concentrated NH4OH for oxidation of L-arabinose. A standard curve is determined for each metabolite using solutions of authentic, chemically synthesized samples. (Moore, S.; Link, K. P. J. Biol. Chem. 1940, 133, 293.) Compounds are quantified by 1H NMR using the following resonances: D-xylonic acid (δ4.08, d, 1H); L-arabinonic acid (δ4.24, d, 1H); and L-arabino-1,4-lactone (δ4.64, d, 1H). A modified procedure by Buchert is employed for the purification of D-xylonate. Following treatment with activated carbon and concentration (1-1.1 L to 250 mL) of D-xylonate containing fermentation broth, EtOH (3:1, v/v) is added. After 12 h at 4° C., the precipitated calcium xylonate is filtered and dried under vacuum (95% recovery based on D-xylonate in the crude fermentation broth). Potassium D-xylonate is obtained by passing an aqueous solution of calcium xylonate through a Dowex 50 (K+ form) column (Applied Membranes, Vista, Calif., USA).

1. extractionextract (5 g)
2. additionadded immediately
3. customare grown at 30° C. with agitation at 250 rpm until they
4. customturbid (˜24 h)
5. customare grown at 30° C.
6. custom(t=0 h)
7. temperatureThe culture medium is maintained at pH 6.4 by addition of 2 N H2SO4
8. customA modified procedure by Buchert is employed for the purification of D-xylonate
9. concentrationwith activated carbon and concentration (1-1.1 L to 250 mL) of D-xylonate containing fermentation broth, EtOH (3:1, v/v)
10. additionis added
11. waitAfter 12 h at 4° C.
12. filtrationthe precipitated calcium xylonate is filtered
13. customdried under vacuum (95% recovery

ORD record

ord-c444edcb97ac4b0892a8aca3a8fbdc92

Source dataset

uspto-grants-2011_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07923226B2