What Is Ursolic Acid?

Ursolic acid, formerly Ursolic Acid. Ursolic acid has a high content of glossy prismatic (anhydrous ethanol) or fine wool-like needle crystals (dilute ethanol), and a low content of brownish yellow or yellow-green powder. A pentacyclic triterpenoid.

[Product name] Ursolic acid

[English name] Ursolic Acid

[English alias] 3beta-Hydroxyurs-12-en-28-oic acid; (3beta) -3-hydroxyurs-12-en-28-oic acid; (3beta, 5xi, 18alpha) -3-hydroxyurs-12-en- 28-oic acid; (3beta) -3-hydroxyurs-12-en-28-oate

[Alias]

CAS number: 77-52-1

MDL number: MFCD00009621

EINECS number: 201-034-0

BRN number: 2228563

PubChem number: 24900660 ^[2]

Properties: Large and shiny prisms (anhydrous ethanol), fine needle-like crystals (dilute ethanol)

Melting point (ºC): 285 288

Specific rotation (º): [] D25 + 67.5 ° (c = 1,1mol / L potassium hydroxide ethanol solution)

Soluble in acetone, soluble in hot glacial acetic acid and 2% sodium hydroxide ethanol solution, insoluble in water and petroleum ether ^[3]

Molar refractive index: 133.52

Molar volume (m3 / mol): 415.7

Isotonic specific volume (90.2K): 1076.7

Surface tension (dyne / cm): 44.9

Polarizability (10-24cm3): 52.93 ^[4]

1. Reference value for calculation of hydrophobic parameters (XlogP): 7.3

2. Number of hydrogen-bonded donors: 2

3. Number of hydrogen bond acceptors: 3

4. Number of rotatable chemical bonds: 1

5. Topological molecular polar surface area (TPSA): 57.5

6. Number of heavy atoms: 33

7. Surface charge: 0

8. Complexity: 874

9. Number of isotope atoms: 0

10. Determine the number of atomic stereocenters: 10

11. Uncertain number of atomic stereocenters: 0

12. Determine the number of chemical bond stereocenters: 0

13. Uncertain number of chemical bond stereocenters: 0

14. Number of covalent bond units: 1 ^[4]

This product is sealed ^[2]

It exists in many plants such as the whole grass of the labiatae plant Prunella vulgaris L., the leaves of the holly family Ilex rotunda Thunb.

1. Extraction of ethanol and methanol The extraction of ursolic acid generally uses ethanol and methanol, and the extract is then separated and purified. One method is to concentrate the extract under reduced pressure for extraction and separation using petroleum ether, chloroform, and ethyl acetate, which is costly and causes serious pollution. The other method is to concentrate the extract under reduced pressure, and use a silica gel column or cross-linked glucose. Glycan gel column separation and enrichment. Using this process, the column packing cost is high, the process is complicated, and toxic organic solvents are often used as eluents, which pollute the environment. In addition, the use of macroporous adsorption resin to separate the extract has a better effect. . Ren Xiulian et al. Studied the process of extracting ursolic acid from Kuding tea by precipitation-adsorption method. The Kuding tea was first extracted with ethanol, and the extract was alkalized to a pH value of 10.96% with a 10% NaOH solution. The impurities such as polyphenols were removed by filtration. After precipitation, the filtrate was first acidified with 10% sulfuric acid to a pH of 4.00, and then diluted with the same volume of an acidic aqueous solution with a pH of 4.00 to obtain a crude product of ursolic acid precipitation. After the product was dissolved in methanol, the pH of the sample solution was adjusted to 7.07, and the pH of the eluent was adjusted to 11.0. It was adsorbed with D-type macroporous resin and eluted step by step to collect the eluate with a volume fraction of 90% ethanol solution. Concentration of the crystals gave the ursolic acid product. After adsorption and separation, the purity of the product was 90.23%, the recovery rate was 98.02%, and the total recovery rate was 89.09%.

2. Hydrolysis by ursolic acid-containing saponin Some ursolic acid exists in the form of saponin in some plant raw materials. Saponin must be hydrolyzed before it can be extracted and separated with a solvent. Saponin can be hydrolyzed by acid or enzyme. The hydrolysis rate of saponin and hydrogen ion Concentrations are related. Organic acids such as 20% acetic acid have almost no hydrolysis effect, and their dissociation constants are also low in sulfuric acid and phosphoric acid solutions. Their catalytic ability is not as good as that of hydrochloric acid and bromic acid at the same concentration. Therefore, hydrochloric acid hydrolysis is commonly used.

When Yuan Chunlan and others extracted ursolic acid from the elm, it was extracted by heating under reflux with ethanol, cooling, filtering, and recovering the alcohol to obtain an extract. The extract was dissolved in water and then extracted with petroleum ether to remove fat-soluble impurities. The aqueous layer Crude saponin was extracted with n-butanol; crude saponin was dissolved in water, saturated with common salt, extracted with n-butanol, the n-butanol layer was washed with water to remove reducing sugars, and n-butanol was recovered to dryness under reduced pressure to obtain refined saponin; refined saponin was added The volume fraction was 7% HCl and 95% ethanol to dissolve it, and the crystals were precipitated by heating under reflux. The hydrolyzed solution was allowed to cool to room temperature, filtered with suction, washed with water, and the precipitate was recrystallized from anhydrous ethanol to obtain white needle-shaped crystalline ursolic acid.

3 The use of supercritical extraction technology for the preparation of supercritical carbon dioxide fluid extraction technology applied to ursolic acid extraction, the selectivity is high, the biological activity of ursolic acid is better maintained, and it is beneficial to the reuse of raw materials after ursolic acid extraction. Conducive to saving resources. It has broad prospects for extracting high value-added ursolic acid. Cui Xingming et al. Used supercritical carbon dioxide fluid to extract ursolic acid in asparagus. The conditions for supercritical fluid extraction are: extraction pressure 40MPa, extraction temperature 60 ° C, and carbon dioxide flow rate 40mL / min. In addition, because ursolic acid is very similar to other triterpenoids (such as oleanolic acid) in the raw material, direct separation is difficult, and ursolic acid can be prepared as a derivative and then separated, such as after esterification. Effective separation of ursolic acid from other triterpene compounds in the raw material can be achieved. After separation and hydrolysis, high-purity ursolic acid can be obtained. ^[2]

An acetonitrile: water (93: 7 by volume) solution was used as the mobile phase and detected by a UV detector at 210nm. The ethanol was dissolved and the reference substance was dissolved at 8-12mg / 25m. ^[2]

(1) Chromatographic conditions: Silica gel G thin-layer plate; cyclohexane-chloroform-ethyl acetate (20: 5: 8) as a developing agent, and spread upward; span 12 to 18 cm; 5% sulfuric acid ethanol solution, heating at 110 ° C 5min color development.
(2) Preparation of reference solution: accurately weigh the appropriate amount of ursolic acid reference, and add a mixed solution of absolute ethanol: ethanol (3: 2) to make a solution containing 1 mg per milliliter as the reference solution.
(3) Preparation of sample solution: Weigh accurately 20g of zongzi pulverized sample (fried zongzi was weighed according to the yield), put it in a Soxhlet extractor, add 300ml of ether to reflux to extract it, and recover the solvent to dryness The residue was soaked with petroleum ether twice, 15ml each time, soaked for about 2min, the petroleum ether was decanted, and the mixture was heated slightly with a mixture of absolute ethanol-ether (2: 3) to dissolve and set in a 5ml volumetric flask as a sample Solution.
(4) Measurement: 2 l of the sample solution and the reference solution were accurately pipetted and spotted on the same thin layer plate. It develops under the above chromatographic conditions and develops color. Scan according to the thin layer scanning method, S = 520nm, R = 700nm; dual-wavelength reflection method sawtooth scanning; SX = 3.0; slit: 1.20mm × 1.2mm; paper speed: 20mm / min. Measure the integrated value of the absorbance of the sample and the reference to calculate the ursolic acid content. ^[2]

Ursolic acid is a triterpene compound present in natural plants. It has various biological effects such as sedation, anti-inflammatory, antibacterial, anti-diabetes, anti-ulcer, and lowering blood sugar. Ursolic acid also has obvious antioxidant functions. Therefore, it is widely used as raw materials for medicine and cosmetics.

Ursolic acid has clinically significant and rapid reductions of alanine aminotransferase, serum aminotransferase, elimination of jaundice, appetite improvement, anti-fibrosis and restoration of liver function. It has the characteristics of quick effect, short course of treatment and stable effect.

Indian scholar Saraswat et al. Found that ursolic acid (5-20 mg · kg) has protective effect on liver toxicity induced by CC1 in rats. Pretreatment with ursolic acid can significantly increase the survival rate of rat hepatocytes, and it has been observed in experiments that ursolic acid has an anti-cholestasis effect, bile flow and its

Li Kaiquan and other studies found that UA, whether used alone or in combination with other drugs in the preparation of drugs for the treatment of viral hepatitis, has a significant effect on the treatment of viral hepatitis as long as it is prepared into medicines or health care drugs. They used oleanolic acid as a control and treated UA with A and B

In recent years, ursolic acid has been found to have anti-carcinogenic, anti-cancer, induction of F9 teratoma cell differentiation and anti-angiogenesis. Studies have found that ursolic acid can significantly inhibit the proliferation and induce apoptosis of HL-60 cells; it can significantly improve the phagocytic function of macrophages in mice. Ursolic acid has a certain toxic effect on sperm. It can destroy the actin of the biliary bridge, open the bridge bond, generate a symptom, and inhibit the formation of sperm. This effect is expected to develop into

Dangerous Goods Mark: Xi
Danger category code: 36/37/38
Safety instructions: 24 / 25-36-26 ^[4]

Ursolic acid safety term

S24 Avoid contact with skin. Avoid skin contact.

S25 Avoid contact with eyes. Avoid eye contact.

S26 In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. After accidental contact with eyes, rinse immediately with plenty of water and seek medical advice.

S27 Take off immediately all contaminated clothing. Remove your clothing as soon as it becomes contaminated.

S28 After contact with skin, wash immediately with plenty of soap-suds. After accidental contact with the skin, rinse immediately with plenty of soap and water.

S29 Do not empty into drains. Never pour into the drain.

S30 Never add water to this product. Never add water to the product.

S33 Take precautionary measures against static discharges. Take measures to prevent static electricity.

S35 This material and its container must be disposed of in a safe way. Handle this substance and its container with care.

S36 Wear suitable protective clothing. Wear appropriate protective clothing. ^[4]

Ursolic acid risk term

R36 / 37/38 Irritating to eyes, respiratory system and skin. Irritation of eyes, respiratory system and skin. ^[4]