1213827-87-2Relevant academic research and scientific papers
Production of Adipic Acid from Sugar Beet Residue by Combined Biological and Chemical Catalysis
Zhang, Hongfang,Li, Xiukai,Su, Xiaoyun,Ang, Ee Lui,Zhang, Yugen,Zhao, Huimin
, p. 1500 - 1506 (2016)
Adipic acid is one of the most important industrial dicarboxylic acids and is used mainly as a precursor to nylon-6,6. Currently, commercial adipic acid is produced primarily from benzene by a chemical route that is associated with environmental, health, and safety concerns. Herein, we report a new process to produce adipic acid from an inexpensive renewable feedstock, sugar beet residue by combining an engineered Escherichia coli strain and Re-based chemical catalysts. The engineered E.coli converted d-galacturonic acid to mucic acid, which was precipitated easily with acid, and the mucic acid was further converted to adipic acid by a deoxydehydration reaction catalyzed by an oxorhenium complex followed by a Pt/C-catalyzed hydrogenation reaction under mild conditions. A high selectivity to the free acid products was achieved by tuning the acidity of the Re-based catalysts. Finally, adipic acid was produced directly from sugar beet residue that was hydrolyzed enzymatically with engineered E.coli and two chemical catalysts in a yield of 8.4 %, which signifies a new route for the production of adipic acid.
Synthesis and conformational analysis of seco C-nucleosides and their diseco double-headed analogues of the 1,2,4-triazole, 1,2,4-triazolo[3,4-b]1,3,4-thiadiazole
Awad, Laila F.,El Ashry, El Sayed H.
, p. 9 - 22 (1998)
Reaction of d-glucono- (1) or d-galactono- (2) 1,5-lactones and d-glycero-d-guloheptonic-1,4-lactone (11) with thiocarbohydrazide (3) afforded the seco C-nucleosides 4-amino-3-(d-gluco- (4) or d-galacto- (5) pentitol-1-yl)-5-mercapto-1,2,4-triazoles and 4-amino-3-(d-glycero-d-gulo-hexitol-1-yl)-5-mercapto-1,2,4-triazole (12). Their conversions to the 3-(1,2,3,4,5-penta-O-acyl-d-gluco- (7 and 9) or the d-galacto (8 and 10) pentitol-1-yl)-6-substituted 1,2,4-triazolo[3,4-b]1,3,4-thiadiazole and 3-(1,2,3,4,5,6-hexa-O-acetyl-d-glycero-d-gulohexitol-1-yl)-6-methyl-1,2,4-triazolo[3,4-b]1,3,4-thiadiazole (13) were achieved under acylative conditions. Reaction of diethyl galactrate (17) with 3 gave 1,4-bis (4-amino-5-mercapto-1,2,4-triazol-3-yl)-galacto-tetritol (18), which upon reaction with acetic anhydride gave 1,4-bis(6-methyl-1,2,4-triazolo[3,4-b]1,3,4-thiadiazol-3-yl)-1,2,3,4-tetra-O-acetyl-galacto-tetritol (19). When the tetra-O-acetylgalactaric acid (15) was used instead of 17, the attack of 3 had taken place on the ester group rather than the carboxylic group, whereby 16 was obtained rather than the tetra-O-acetyl derivative of 18. The structures were confirmed by using 1H,13C and 2D NMR spectra (DQFCOSY and HMQC) experiments. The vicinal coupling constants were used to deduce the favored conformations. Copyright (C) 1997 Elsevier Science Ltd.
Kinetic and mechanistic investigation of oxidation of uronic acids by sodium N-bromoarylsulfonamides in alkaline medium
Shashikala,Rangappa
, p. 491 - 499 (2002)
The kinetics of oxidation of uronic acids (UAs), D-glucuronic acid and D-galacturonic acid, by sodium N-bromo-p-toluenesulfonamide or bromamine-T (BAT) and sodium N-bromobenzenesulfonamide or bromamine-B (BAB) in alkaline medium at 30°C have been investigated and the rate law, rate=k [OX] [UA] [HO-] where [OX][BAT] or [BAB] was observed. The product p-toluenesulfonamide (PTS) or benzenesulfonamide (BSA) and ionic strength have no influence on the rate. The rate decreased when the dielectric constant (ε) of the medium was decreased. The rate increased in D2O medium. Proton inventory studies were made in D2O-H2O mixtures. Effect of temperature was studied and from the Arrhenius plots, activation parameters were computed. A mechanism involving the formation of enediol anion, which reacts with positive bromine of the bromamine in the rate-limiting step is suggested.
Base-free selective oxidation of pectin derived galacturonic acid to galactaric acid using supported gold catalysts
Pazhavelikkakath Purushothaman, Rajeesh Kumar,Klis, F. Van Der,Frissen,Haveren, J. Van,Mayoral,Van Der Bent,Van Es
, p. 2763 - 2774 (2018)
Agricultural residues like sugar beet pulp (SBP) are an interesting feedstock for the production of 2nd generation bio-based chemicals and materials. The pectin fraction of SBP is rich in galacturonic acid (GalA), a C6 sugar acid. The oxidation of this uronic acid at C1 yields galactaric acid (GA), which has several industrially interesting properties. It was previously shown that the Au catalysed oxidation of uronic acids under basic conditions is highly effective, yet leads to the co-production of salts. Hence, here we report for the first time on the oxidation of an acidic carbohydrate substrate, GalA, at its autogenic pH (2.2) in water, using carbon supported gold nanoparticles, under mild conditions in the presence of molecular oxygen. The comparison of the Au/C catalyst prepared by a colloidal deposition method with benchmark commercially available metal oxide supported gold catalysts shows that under acidic conditions, the Au/C catalyst is more active and more selective than Au/TiO2, and more stable than Au/Al2O3. The difference in selectivity is attributed to the H2O2 mediated chain scission reaction of the substrate (GalA) which is observed only in the case of metal oxide supported Au catalysts. The Au/C catalyst shows 100% GA selectivity at 76% GalA conversion (333 K, 21 h batch time) and a GA yield of up to 95% was obtained at 353 K. Detailed characterization of the fresh and spent Au/C catalysts by ICP-OES, TEM and XPS analyses showed no gold leaching, particle sintering or change in metal composition. The Au/C catalyst was fully regenerated by a mild alkaline wash, and used in five consecutive runs without any significant decrease in activity or selectivity. Labelling experiments with 18O2 and H218O2 revealed that under base-free conditions, the oxygen incorporated in the aldaric acid originates from the solvent water.
Biological Activities of Phenolics from the Fruits of Phyllanthus emblica L. (Euphorbiaceae)
Zhang, Jie,Miao, Dan,Zhu, Wan-Fang,Xu, Jian,Liu, Wen-Yuan,Kitdamrongtham, Worapong,Manosroi, Jiradej,Abe, Masahiko,Akihisa, Toshihiro,Feng, Feng
, (2017)
Seven phenolic compounds, 1 – 7, including a new organic acid gallate, mucic acid 1-ethyl 6-methyl ester 2-O-gallate (7), were isolated from the MeOH extract of the fruits of Phyllanthus emblica L. (Euphorbiaceae). The structures were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. Upon evaluated for their antioxidant abilities by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. The inhibitory activities against melanogenesis in B16 melanoma cells induced by α-MSH, as well as cytotoxic activities against four human cancer cell lines were also evaluated. All phenolic compounds, 1 – 7, exhibited potent antioxidant abilities (DPPH: IC50 5.6 – 12.9 μm; ABTS: 0.87 – 8.43 μm Trolox/μm; FRAP: 1.01 – 5.79 μm Fe2+/μm, respectively). Besides, 5 – 7, also exhibited moderate inhibitory activities against melanogenesis (80.7 – 86.8% melanin content), even with no or low toxicity to the cells (93.5 – 101.6% cell viability) at a high concentration of 100 μm. Compounds 1 – 3 exhibited cytotoxic activity against one or more cell lines (IC50 13.9 – 68.4%), and compound 1 with high tumor selectivity for A549 (SI 3.2).
Lamiaceae carbohydrates. 1. Pectinic substances and hemicelluloses from Mentha x piperita
Olennikov,Tankhaeva
, p. 501 - 507 (2007)
Pectinic substances from the aerial part of Mentha x piperita were isolated and characterized and found to be a mixture of β-(1→4)-glucogalactan (MPG) and two α-(1→4)-rhamnopolygalacturonans (MPP'-1 and MPP'-2). It was shown that the pectin and its components exhibited membrane-stabilizing, antiatherogenic, and antioxidant activity. Hemicelluloses from M. piperita were a lignocarbohydrate complex.
Kinetics and mechanism of the oxidation of uronic acdis by sodium N-chlorobenzenesulphonamide in alkaline medium
Rangappa,Raghavendra,Mahadevappa
, p. 359 - 371 (1997)
The kinetics of oxidation of D-glucuronic acid and D-galacturonic acid (UA) by sodium N-chlorobenzenesulphonamide or chloramine-B (CAB) in alkaline medium at 35°C has been investigated and the rate law, rate = k [CAB][UA][HO-] was observed. The product, benzenesulphonamide had no influence. Increase of ionic strength increased the rate and when the dielectric constant of the medium was decreased, the rate was decreased. The rate increased in D2O medium and the inverse solvent isotope effect k (D2O)/k (H2O) was 2.00. Proton inventory was studied for the reactions in H2O-D2O mixtures. Activation parameters have been determined from the Arrhenius plots. The mechanism assumes the formation of an enediol anion followed by its oxidation by the positive halogen in a rate limiting step.
PROCESSES FOR PREPARING ALDARIC, ALDONIC, AND URONIC ACIDS
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Paragraph 0132-0143, (2021/05/29)
Various processes for preparing aldaric acids, aldonic acids, uronic acids, and/or lactone(s) thereof are described. For example, processes for preparing a C5-C6 aldaric acid and/or lactone(s) thereof by the catalytic oxidation of a C5-C6 aldonic acid and/or lactone(s) thereof and/or a C5-C6 aldose are described.
OXIDATION OF URONIC ACIDS TO ALDARIC ACIDS
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Paragraph 0032; 0037, (2017/11/10)
Disclosed is the oxidation of uronic acids, such as galacturonic acid, to the corresponding aldaric acids, such as galactaric acid, under neutral or acidic conditions. Use is made of a supported gold catalyst. The oxidation occurs in good selectivity and yield, under unexpectedly mild conditions. A source of galacturonic acids is pectins, such as from sugar beet pulp.
Novel synthetic process of mucic acid
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Paragraph 0035-0037; 0067, (2017/06/10)
The present invention relates to a method of synthesizing mucic acid from galactose derived from biomass including marine resources, and more specifically, to a method of synthesizing mucic acid which utilizes galactose as a starting material and through a chemical reaction, induces an oxidation reaction to synthesize mucic acid. The method of the present invention can easily synthesize mucic acid in a high yield from galactose and the like under low temperature and atmospheric pressure operating conditions, can be used as an intermediate to produce bio adipic acid, the raw material of nylon 66 that is used as a material for automobile parts, and, therefore, has high industrial applicability.(AA) Marine bio sugar mixture obtained after saccharification using non-food marine resources (galactose, or a mixture of galactose, glucose and rhamnose)(BB) Mixing of aqueous nitric acid solution with sugar mixture(CC) Oxidation reaction of bio sugar under low temperature condition (-15~0anddeg;C)(DD) Washing of solid products produced from chemical reaction and extraction of high-purity mucic acid particles using aqueous solution, having mucic acid dissolved therein, prepared in advanceCOPYRIGHT KIPO 2017
