Chapter 260 Artemisia annua
Li Ang stood up abruptly, and asked Qiu Feng, "Is there wormwood in the ward?"
"some."
Qiu Feng nodded and said, "It's in the warehouse."
Li Ang and Qiu Feng went to the warehouse and found Artemisia argyi in the medicine cabinet.
This kind of medicinal material is used as a medicine for clearing away heat, relieving heat, cooling blood and external use in Pharmacopoeia.
In botanical classification, Artemisia annua is actually the collective name of two Artemisia plants—Artemisia annua and Artemisia annua.
Both are dicotyledonous plants, Asteraceae, Artemisia annual herb, taste similar, the same color.
The difference is that the inflorescence head of Artemisia annua is nearly spherical, the inflorescence is small, the leaves are mostly three to four times pinnately divided, the fruit is oval-ovate, slightly flat, and the flowering and fruiting period is at the end of summer
The inflorescence head of Artemisia annua is hemispherical, the inflorescence is relatively large, the leaves are mostly two to three times comb-toothed and pinnately divided, the fruit is oblong, and the flowering and fruiting period is in mid-summer.
In the memories of other worlds, artemisinin extracted from these two Artemisia species is used to kill Plasmodium falciparum and treat malaria. The process of artificially synthesizing artemisinin has also won the highest scientific research award because of its great significance to all mankind.
‘The killing mechanism of artemisinin on Plasmodium is multifaceted. It can not only induce the mitochondrial swelling of Plasmodium, generate a large amount of active oxygen free radicals, and destroy the biofilm system of Plasmodium,
It can also be directly attached to the protein of the malaria parasite through the carbon atom, and it can kill the malaria parasite by taking advantage of the fact that the alkylated protein cannot work normally’
Countless materials flashed through Li Ang's mind. He never thought of artificially synthesizing artemisinin.
One is because artificial synthesis is too cumbersome and difficult, it is better to directly refine it at this stage,
The second reason is that artemisinin is not a specific drug against schistosomiasis.
A derivative of artemisinin, artesunate, is.
——
First, artemisinin is extracted.
Take the old Artemisia annua leaves and grind them to get Artemisia annua coarse powder.
Soaked in 60% ethanol, percolated for six hours,
The leachate is decolorized by activated carbon, filtered by suction, and green leaves are obtained.
Through the macroporous adsorption resin, adsorbed, and then eluted with high-concentration ethanol,
Obtain the eluate, depressurize below 60 degrees Celsius, precipitate the crude product, and recrystallize with ethanol to obtain relatively pure artemisinin.
In the second process, the most difficult part is the resin adsorption.
Macroporous adsorption resin refers to a kind of polymer adsorption resin without exchange groups and has a macroporous structure. It has a good macroporous network structure and a large specific surface area, and can adsorb organic substances in aqueous solution.
Li Ang chose to use styrene as raw material to make macroporous adsorption resin.
First, benzene is separated from coal pyrolysis oil by means of distillation,
Then mix ethanol and concentrated sulfuric acid in a ratio of 1:3, and heat it rapidly to 170 degrees to produce ethylene.
Finally, the original process is used to pass benzene and ethylene through the catalyst bed under the conditions of 400 Baidu and 2Mpa to obtain styrene.
Obtaining artemisinin is only the beginning.
First of all, ether solvent, tetrahydrofuran must be obtained.
In the reactor, put ethanol, and magnesium oxide and silicon dioxide as catalysts, under the condition of 360 to 370 degrees, catalyze dehydrogenation and dehydration to generate butadiene.
Using butadiene as raw material, furan is obtained through oxidation, and then hydrogenated to obtain tetrahydrofuran.
In the tetrahydrofuran solvent system, use borohydride as the reducing agent to obtain dihydroartemisinin, add phosphoric acid to adjust the pH value to neutral, add succinic anhydride, and carry out acylation reaction to prepare artesunate.
And by means of extraction, crystallization and recrystallization, purer medical grade artesunate is obtained.
(Paraffin wax is oxidized under the catalysis of calcium and manganese to obtain mixed dibasic acid oxidized paraffin wax, which is distilled by hot water steam to obtain succinic acid)
The whole process is cumbersome and complicated, even higher than penicillin.
Even if you know all the procedures, have enough material resources and manpower, and can drive monks at will,
The entire plan, experiment, and test still took Li Ang a month.
But in the end, looking at the white crystals of artesunate, it was all worth it.
Artesunate not only has the function of killing malaria parasites efficiently like artemisinin, but also targets and kills schistosomiasis juveniles.
In areas severely affected by water poisoning, artesunate was given to infected patients who were briefly exposed to infested water, and the insect reduction rate reached 99%.
Infected patients who have been exposed to infested water for a long time, after taking it, the insect reduction rate can reach more than 80%.
Moreover, the side effects of artesunate are extremely low, taking the medicine once every 15 days is enough to last until the enucleation method to completely eradicate schistosomiasis.
"Put the medicine together with the instructions for use, and distribute it."
Li Ang said to the person in charge of the ward.
It is not surprising that Artemisia annua cures diseases as described in medical books.
And the production process is too complicated for ordinary people to understand
In the past, there were alchemy, alchemy, leaching, distillation, evaporation, burning, sublimation, crystallization, water bath and other processes, all of which have precedents.
"After confirming the efficacy of artesunate, our mission in Suzhou will be completed."
Li Ang turned his head to look at Qiu Feng. Because of his experience in preparing penicillin last time, he also invited Qiu Feng to help in preparing artesunate this time.
"Yeah. Nearly three months. Thinking about it now, it feels like three years."
Qiu Feng sighed, then turned his head to look at the plaque in the hospital.
In the past three months, the ward has been continuously expanded. The sweat and tears of all medical staff have been invested here, and countless life and death have been witnessed.
The two stood side by side, looking at the plaque, neither of them spoke.
After a long time, Li Ang looked away, and said with a smile: "When we return to Chang'an, maybe we can catch up with the tail of the academic exchange. I will apply to the head of the mountain at that time, and use this credit to reduce our leave. Operation."
"It's best to go back a few days later, and escape the midterm exam by the way."
Qiu Feng smiled and made a joke, feeling a little melancholy in his heart.
Li Ang noticed the expression on her face, and comforted him: "It doesn't matter, the imperial court sees the benefits of the hospital mechanism.
Jiangnan East Road is financially rich, with many workshops, and the income of the people is higher.
Relying on financial support and medical expenses, even if there is no water poisoning epidemic, the hospital can continue to operate. It won't fall. "
"Um."
Qiu Feng nodded emphatically. If she hadn't had the experience of being a doctor in the infirmary this time, she would never have imagined that in the richest Jiangnan East Road in Yu State, there are still so many people who lack medical care and medicine.
"The hospital mechanism can not only help the people to the greatest extent, but also cultivate young doctors and improve their medical practice level in the shortest time.
After returning to Chang'an, I will submit a letter to the imperial court to establish a medical college and enrich the medical clinics in various places. "
Li Ang looked at the people queuing up outside the ward, and said slowly.
A person's power is limited, no matter how talented he is, he cannot solve all problems.
Rather than being a single doctor, personally treating diseases and saving lives, it is better to spread knowledge and cultivate more doctors.
Li Ang turned his head, met Qiu Feng's surprised eyes, and said with a smile: "You have worked hard this time, go back to the room and have a rest."
Qiu Feng asked: "What about you?"
"I'll go to the Suzhou Library to consider the words and sentences in the book."
Li Ang smiled slightly, he really wanted to establish a medical school system.
In addition, once the water poisoning issue is resolved, it is time to investigate the sea-going ship named "Wujun Changmen Sea Falcon Thirty-Nine" that is related to the source of Mosi.
(end of this chapter)