Product name: D(+)-Xylose
CAS: 58-86-6
Molecular formula: C5H10O5
EINECS: 200-400-7
Introduction
D-xylose is the main structural unit of hemicellulose. It is not only the most abundant pentose on earth, but also the second most abundant monosaccharide in nature (after glucose). Natural D-xylose is widely present in the hemicellulose of plant cell walls in the form of polysaccharides (xylan). It is higher in hardwood and grass plants, usually between 20-25%. The xylan content in birch bark, corn cobs and bagasse is the highest, usually between 25-30%. Therefore, D-xylose is mostly extracted from plants. D-xylose has similar chemical properties to glucose and can be reduced to the corresponding alcohol, such as xylitol.
D-Xylose Properties
| Melting point | 154-158 °C(lit.) |
| Specific rotation | 20 º (c=10, H2O) |
| Boiling Point | 191.65°C (rough estimate) |
| Bulk density | 450kg/m3 |
| Density | 1.525 |
| Refractive Index | 20 ° (C=10, H2O) |
| FEMA | 3606 | D-XYLOSE |
| Flash point | > 100°(212°F) |
| Storage conditions | Sealed in dry,Room Temperature |
| Solubility | H2O:1 Mat 20 °C, transparent, colorless |
| Form | Fine crystalline powder |
| Acidity coefficient (pKa) | pKa (18°): 12.14 |
| Color | White |
| Odor | Odorless |
Chemical properties
Colorless to white crystals or white crystalline powder, with a slightly special smell and refreshing sweetness. The sweetness is about 40% of sucrose. Relative density 1.525, melting point 114℃, dextrorotatory and mutarotatory, specific rotation [α] D20 +92°～+18.6°. Soluble in water (125g/100m1) and hot ethanol, insoluble in ethanol and ether. Cannot be digested or utilized by the human body. Natural products exist in many mature fruits.
Uses
D-xylose is a naturally derived reducing five-carbon monosaccharide with a sweetness of 50% of sucrose. It is mainly extracted from hemicellulose-rich plants such as corn cobs.
Currently, D-xylose has two main applications:
(1) for further processing to synthesize xylitol;
(2) for efficient Maillard reaction to enhance flavor and color. In addition, D-xylose is also widely used in food production, flavors and fragrances, cosmetics and other fields. At the same time, D-xylose acid, as one of the 30 most promising high-value bio-based platform products, has become a multi-purpose material, widely used in the synthesis of 1,2,4-butanetriol, concrete additives and green and efficient biocatalysts for organic conversion.
Solubility in water (g/100ml)
Number of grams dissolved in 100ml water: 117g/20℃
Identification test
Add 2-3 drops of 5% sample aqueous solution to 5ml hot Fehling's test solution (TS-80), and a red precipitate should be produced.
Take 1g of the sample and add 25ml of water that has just been boiled and cooled to dissolve it. The solution is right-handed.
Take 1g of the sample, add 3ml of water, dissolve it in warm water, add 3ml of a mixture of 4ml of 2.5% benzidine ethanol solution and 10ml of dilute hydrochloric acid test solution (TS-117), heat it in a water bath for 5 minutes, and the solution should be yellow to light orange.
Take 0.5g of the sample, add 20ml of water, dissolve it, add 30ml of phenylhydrazine hydrochloride/sodium acetate test solution (TS-169) and 10ml of dilute acetic acid solution (TS-2), and heat it in a water bath for about 2h. The resulting precipitate is recrystallized with water, and its melting point is 160-163℃.
Efficacy and effects
D-xylose, as an emerging functional food ingredient, is widely used in various functional foods due to its excellent processing characteristics and multiple physiological regulation functions. Its physiological regulation functions mainly include the following aspects:
(1) Regulating intestinal flora and promoting the proliferation of bifidobacteria: D-xylose can selectively promote the proliferation of beneficial bacteria such as intestinal bifidobacteria, making them the dominant intestinal flora, regulating the balance of intestinal microecology, and promoting intestinal health.
(2) Lowering blood pressure, serum cholesterol and blood sugar: D-xylose is a water-soluble dietary fiber and has some physiological functions of dietary fiber. D-xylose has a good effect on preventing hyperlipidemia.
(3) Low in calories: D-xylose is difficult to be decomposed by the human digestive enzyme system. Saliva, gastric juice, pancreatic juice and small intestinal juice can hardly decompose D-xylose, and its energy value is almost zero. Therefore, D-xylose can be used as a raw material for weight loss foods and blood sugar regulating foods.
(4) Anti-caries: Oligosaccharides do not cause tooth caries. Caries is caused by the erosion of oral microorganisms, especially mutans streptococci. D-xylose cannot be used by oral bacteria and cannot be broken down by oral enzymes.
Uses
D-xylose is mainly used to make xylitol, which is used as a non-caloric sweetener in food and beverages, suitable for obese and diabetic patients. It is also used as a fat oxidation inhibitor, a raw material for making sauce color, and for preparing pork and other spices through the Maillard reaction. Xylose has a high proliferation effect on bifidobacteria in the human intestine. Eating xylose can improve the microbial environment of the human body. It improves the body's immune ability. Xylose is very compatible with food. Adding a small amount of xylose to food can show a good health effect. Taking xylose and calcium at the same time can improve the body's absorption and retention rate of calcium, and can also prevent constipation.
Production method
It is made by acid hydrolysis of corn cobs, with a yield of 12%. Wood and acid are hydrolyzed to hydrolyze the hemicellulose xylan in the wood into D-xylose. Yeast and fermentation are then used to remove glucose and then refined and concentrated.
