Magnolia Bark Extract

1. Alkaline extraction and acid precipitation method

Take Magnolia officinalis crude powder, add 1/5 amount (w /w ) of lime powder, mix well, with 15 ~ 20 times the amount of distilled water percolation, get the percolation solution. Add HC1 solution to pH2 ~ 3, stand, collect the precipitate precipitation, with distilled water to wash the precipitate to pH6 ~ to get the crude extract after drying, with cyclohexane Soxhlet extraction, the extract is concentrated and cooled to precipitate white crystals.

2. Water extraction method

Take the crude powder, add 5 ~ 10 times the amount of water, volatile volatile oil with NaOH adjusted to Q 2mol·L^-1 alkaline solution. Place 24 h, centrifugal filtration, the filtrate with ether extraction 3 times, the aqueous layer with dilute HC1 solution adjusted to pH2 ~ 3, with ether and then extracted 5 times, combined ether solution with 2% Na₂CO₃ washing and drying with anhydrous ethanol Na₂SO₄, placed in the night, evaporate the ether solution to get the crystals. The crystallization was recrystallized with water for 1 time, and the yield of the product was about 4%, which was less.

3. Ethanol extraction method

The crude powder of Magnolia officinalis was extracted with 65% ethanol (the amount of ethanol was 5 times of the amount of herbs), heated and refluxed for 3 times, each time for 2 h, and the extracts were combined. The results showed that the extraction rate of the phenols was more than 80%. This method is a traditional industrial extraction method with high content of thujaplicin and high yield of thujaplicin extract.

4. Polyamide separation and extraction method

Take the powder of the herb, extract with ethanol, recover ethanol to get thick paste. After polyamide column, first rinse with Q 5%, Q 8%, 1% NaOH gradient, the wash solution with dilute HC1 solution to acidic, precipitation of crystals, can be separated from thujaplicinol and thujaplicinol, its Q 5% ~ Q 8% NaOH eluted portion of thujaplicinol and thujaplicinol, 1% NaOH eluted portion of thujaplicinol.

5. Alkali resin extraction process

Take the Magnolia officinalis cut into pieces, add Q 5% alkali solution at 95 ~ 99 ° C water bath temperature immersion 2 times, respectively, after filtration and combined filtrate, add 6mol·L^-1HC1 solution to adjust the pH to 7. Will be the liquid over the resin column, with 95%, 75% ethanol successive elution (the last eluent is nearly colorless), combined with the eluent, the concentration of the crystals. This process is of low cost and high extraction rate of the phenolics, but with more impurities.

6.Supercritical CO₂ extraction

The crude powder of Magnolia officinalis was put into the extraction kettle, and the separation column of the extraction kettle was subjected to high pressure and temperature of CO₂, when the pressure and temperature reached the requirements of the process, i.e., the thermodynamic state was above the critical point, then the cycle of extraction was started. After a certain period of time, the active ingredient was analyzed by the decompression of the separation column, and a light yellow paste was obtained, and the extraction rate of total thujaplicin was 80%. This method has high efficiency, good quality and retains the characteristics of the original drug, which is an advanced industrial extraction method.