D-葡萄糖醛酸,D-Glucuronic acid

THOA is also known as D-gluconic acid or D-glucono-1,5-lactone. It is a white crystalline powder that is soluble in water and has a sour taste. THOA is commonly used in the food and beverage industry as an acidulant, flavor enhancer, and preservative. It is also used in the pharmaceutical industry as a chelating agent and in the cosmetic industry as a skin conditioning agent.

Physical and Chemical Properties:

THOA has a molecular formula of C6H10O7 and a molecular weight of 194.14 g/mol. It is a cyclic six-membered lactone ring that is formed by the intramolecular esterification of the carboxylic acid group with the hydroxyl group located on the fifth carbon of the same molecule. THOA is a weak acid with a pKa of 3.86, which means that it can donate a proton in solution, but it is only partially ionized. It has a melting point of 151-155°C and a boiling point of 457.6°C at 760 mmHg.

Synthesis and Characterization:

THOA can be synthesized by the oxidation of D-glucose with the enzyme glucose oxidase. The reaction produces D-glucono-1,5-lactone, which can then be hydrolyzed to THOA by adding water and heat. THOA can also be obtained from the hydrolysis of gluconic acid, which is produced by the fermentation of glucose by certain bacteria such as Gluconobacter oxydans. Its chemical structure can be characterized using various spectroscopic techniques such as infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy.

Analytical Methods:

THOA can be quantified using various analytical methods such as high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). These methods are used to determine the purity, concentration, and composition of THOA in various samples.

Biological Properties:

THOA has been shown to have various biological properties such as antimicrobial, antioxidant, and anti-inflammatory activities. It has been reported to inhibit the growth of bacteria such as Escherichia coli and Salmonella typhimurium. It also has the ability to scavenge free radicals and protect cells from oxidative damage. In addition, it has been shown to reduce inflammation and improve wound healing in animal models.

Toxicity and Safety in Scientific Experiments:

THOA is generally considered to be safe for human consumption. It is classified as a GRAS (Generally Recognized As Safe) substance by the US FDA. In scientific experiments, THOA has been shown to be non-toxic and non-carcinogenic. However, it should be used with caution as it may cause irritation to the skin and eyes in its pure form.

Applications in Scientific Experiments:

THOA has a wide range of applications in scientific experiments. It can be used as a standard for the calibration of analytical instruments such as HPLC and GC-MS. It can also be used as a substrate for enzymes such as glucose oxidase and lactonase. In addition, it can be used as a model sugar acid for the study of various biological processes such as carbohydrate metabolism and signaling pathways.

Current State of Research:

Recent studies have focused on the development of novel methods for the synthesis of THOA and its derivatives. Researchers have also investigated the potential of THOA as a therapeutic agent for the treatment of various diseases such as diabetes and cancer. Moreover, the use of THOA as a bio-based chemical for the production of biodegradable plastics and other materials is also being explored.

Potential Implications in Various Fields of Research and Industry:

THOA has the potential to make a significant impact in various fields of research and industry. In the food and beverage industry, it can be used as a natural acidulant and preservative. In the pharmaceutical industry, it can be used as a chelating agent and a drug delivery system. In the cosmetic industry, it can be used as a skin conditioning agent. In the agriculture industry, it can be used as a fertilizer and a soil amendment. Moreover, its potential as a bio-based chemical can lead to the development of sustainable products and materials.

Limitations and Future Directions:

Despite its many potential applications, THOA still has some limitations that need to be addressed. Its high cost of production and purification may hinder its widespread use in various industries. Moreover, its stability under different conditions still needs to be determined. Future research should focus on the development of cost-effective and environmentally friendly methods for the synthesis and purification of THOA. In addition, the investigation of its medicinal properties and potential therapeutic applications should also be continued. Potential future directions for research on THOA include the exploration of its role in the gut microbiome and its use as a biofilm inhibitor for medical and industrial applications.

Literature References: 

Widely distributed in the plant and animal kingdoms. Usually occurs in "paired" form, i.e. as a glycosidic combination with phenols, alcohols, etc. Such glucuronides form in the liver to detoxify poisonous hydroxyl-containing substances. The glucuronides present in normal urine are those of phenol, cresol, and indoxyl. After the ingestion of poisons such as morphine, chloral hydrate, camphor, or turpentine, glucuronides formed with the poison or its hydroxylated derivatives appear in the urine. Review and bibliography: Stacey, Adv. Carbohydr. Chem. 2, 161 (1946); Jones, Smith, ibid. 4, 243 (1949). Structure: Pryde, Williams, Nature 128, 187 (1931); Levene, Meyer, J. Biol. Chem. 92, 257 (1931); Levene, Kreider, ibid. 120, 597 (1937). 

Review of syntheses: 

Mehltretter, Adv. Carbohydr. Chem. 8, 231 (1953). Prepn by irradiation of D-glucose in dil aq soln: Phillips et al., J. Chem. Soc. 1958, 3522; by g-irradiation of aq sucrose soln: Phillips, Moody, ibid. 1960, 762. Electrophoretic sepn of D-glucuronic acid and its C-5 epimer, L-iduronic acid: I. Miyamoto, S. Nagase, Anal. Biochem. 115, 308 (1981). Monographs: N. E. Artz, E. M. Osman, Biochemistry of Glucuronic Acid (Academic Press, New York, 1950); G. J. Dutton, Ed., Glucuronic Acid, Free and Combined (Academic Press, New York, 1966) 629 pp.

Derivative Type: b-Form

Properties: Needles from alcohol or ethyl acetate. mp 165°. Shows mutarotation: [a]D24 +11.7° ? +36.3° (2 hrs, c = 6). Soluble in water, alcohol. Reduces Fehling's soln.

Melting point: mp 165°

Optical Rotation: [a]D24 +11.7° ? +36.3° (2 hrs, c = 6)