Molecular Formula | [-NHCH(CO2R)CH2CO-]n,R=HorNa |
Molar Mass | 177.066 |
Density | 1,21 g/cm3 |
Melting Point | -10 to -20°C |
Boling Point | 106 °C |
Flash Point | 113 °C |
Storage Condition | -20℃ |
Refractive Index | 0 |
Abstract:
DL-aspartic acid was synthesized from maleic anhydride (maleic anhydride) in a titanium autoclave. Through the experimental study of the original synthesis process has been improved, so that the product yield increased to more than 70%, and the separation and purification of products using maleic acid (maleic acid) instead of hydrochloric acid, the acidified crystallization improves the utilization of the reactants and reduces the contamination of the reaction residues. View all>
Key words:
DL-aspartic acid maleic anhydride ammoniation
DOI:
10.3969/j.issn.1671-3206.2002.03.009
cited:
year:
2002
CN201610092960.4
application date:
2016-02-20
Public/Announcement Number:
CN105506016A
Public/announcement date:
2016.04.20
applicant (patent):
Jiang Guangyu
inventor:
National and provincial code:
CN340225
Abstract:
The invention discloses a method for enzymatic production of DL-aspartic acid, which belongs to the field of bioengineering. The method uses aspartic acid racemase to racemize L-aspartic acid to produce DL-aspartic acid, the method comprises the following steps: L-aspartic acid is dissolved by adding an alkaline substance to form an L-aspartic acid saline solution as a substrate for the enzymatic reaction; Aspartic acid racemase is added to the substrate solution to control the reaction temperature for the enzymatic reaction; after the completion of the reaction, filtering, heating and adding activated carbon to decolorize, after cooling, sulfuric acid is added to the clear solution to adjust the pH, so that DL-aspartic acid crystallizes out from the solution, and after cooling, it is filtered and washed, dry available DL-aspartic acid product. The production method has the advantages of easy availability of raw materials, simple production process, mild reaction conditions and low production cost of DL-aspartic acid.
Abstract:
Objective to study the antagonistic effect of poly (DL-aspartic acid) (PAA) on gentamicin (GM) ototoxicity in F-344 rats. Methods 50 healthy F-344 rats were randomly divided into 4 groups: I was GM, II was PAA GM, III was PAA, IV was normal saline control group, the threshold of auditory brainstem response (ABR) at different frequencies was changed; Cochlear hair cells Mortality Rate were counted to observe the antagonism of PAA on the ototoxicity of GM in F-344 rats; the effect of PAA on the antibacterial activity of GM was observed by two-way diffusion serum medium assay. ResultsKey words:
aspartic acid gentamicin Drug antagonism ototoxicity deaf
DOI:
CNKI:SUN:ZHEB.0.1999-04-010
year:
1999
Author:
Li Jiamin , Li supercolumn Li Shangping
Abstract:
The structure of DL-aspartic acid was characterized by X-ray single crystal diffraction and IR. The organic compound belongs to monoclinic system, P21 space group, unit cell parameters: a = 5.1353(8)A, B = 6.9713(11)A,c = 76073(11)A,a = 90 °,β = 9.812(3)°, strict 90 ° molecular formula: C4H7NO4,Mr = 133.11,V = 268.36(7)A3,Z = 2,Dc = 1.647Mg/m ^ 3,R1=0.0468,wR2=0.0683[I>2 & sigma;(I)]. In the crystal structure, organic molecules pass through intermolecular hydrogen bonds N-H... O and O-H... O assembled into a three-dimensional network of supramolecular structures.
Key words:
DL-aspartic acid infrared spectrum crystal structure
DOI:
10.3969/j.issn.1007-1865.2009.08.015
cited:
year:
2009