Her and Dr. Yu's work was progressing in an orderly manner in tension and busyness. A week later, their efforts showed initial results. After many failures and tests, under a microscope, they successfully observed a white sterile circle they expected in the Staphylococcus petri dish.

This means that they have obtained a valuable strain of bacteria that produces antibiotics.

The excited Dr. Yu asked Su Xuezhi to name this strain.

Su Xuezhi named it w number one.

w is the first pronunciation of the surname of Dr. Wu who died.

Dr. Yu was silent for a moment, thanked Su Xuezhi, and said, "We will have W No. 2, No. 3, No. 4... Although Qinghe left, his reputation is immortal. If he knows it in the spring, he should be relieved."

Laboratory work continues to advance.

The precious bacterial strains were obtained after isolation, and the next step was culture and fermentation.

The current cultivation methods of many bacterial species are generally adopted by solid surface culture fermentation. Dr. Yu is also familiar with this method. However, Su Xuezhi does not recommend it.

Although she is not a professional microbiologist, she also knows that Penicillium is very "delicate" and requires purebred fermentation. When the culture medium on the surface is exposed to the air, various microorganisms will cause a lot of pollution, making it difficult to control the fermentation process and quality. Even if it is produced, the fermentation price of mold is often very low, and the purity does not have the value of refining and using it as a drug.

She suggested using the liquid culture medium method. In a fixed container, sterile air is used for culture and fermentation.

There is no precedent to follow, and Su Xuezhi regrets that he had not studied the manufacturing process of Penicillium in detail before, and now he can only explore everything.

For Dr. Yu, Penicillium is a new strain that he had never been exposed to before. After preserving the parent strain and testing and comparing the two culture methods of solid and liquid, he decisively adopted Su Xuezhi's suggestion and carried out the liquid culture method with all his might.

The first time they cultivated 100 portions, each of which was about 200 ml of liquid culture medium. After successfully inoculating, in the following time, Su Xue almost soaked in the laboratory day and night, observing the growth of mold at all times.

After three to four days at room temperature, the surface of the culture medium gradually grew mold, and after four or five days, the color turned blue and golden drip-like water droplets appeared.

The more water droplets, the better, indicating that the mold is not contaminated and grows vigorously.

This kind of picture, when Su Xuezhi's eyes, is simply the most perfect and precious famous painting in the world.

Even if someone wants to exchange Mona Lisa's smile with her, she won't change it!

She spent a week in excitement and finally got what she wanted. She refrigerated the culture medium she obtained and waited for the next step of extraction.

Now there are three steps left before their experiment is successful.

The first step is to separate the penicillium solution from the culture solution to obtain pure penicillium extract.

The second step is to test the medicinal properties.

In the last step, freeze-drying to obtain crystallization.

The laboratory is equipped with an industrial cold box, and refrigeration and storage are not a problem.

During the separation and extraction stage, Dr. Yu and Su Xuezhi slowly adjusted after several failures. On this day, she adjusted the pH of the culture medium to ph2.0, then added amyl acetate and shook it gently to make it mix thoroughly.

The scene that Su Xuezhi was looking forward to finally happened.

The penicillin-containing amyl acetate floats on the surface and is completely separated from the lower layer of bacterial fluid, clearly distinguishing it!

After that, it went smoothly. Under the guidance of Dr. Yu, it was repeatedly extracted with distilled water of ph7.0. After several times, the charcoal was decolorized, chloroform was refined, and finally dissolved in sterile water.

At this point, the refining was finally completed and they obtained the first pure laboratory penicillin solution.

Even though he was excited, Su Xuezhi was actually very clear that the penicillin obtained using this method in the laboratory will not have a high titer.

This is the world's first artificial laboratory culture to obtain pure penicillin. There are no ready-made standards for calibration, but according to her estimates, it should not exceed forty or fifty Oxford units per milliliter.

It is still very far from being able to be mass-industrial production.

Next, they need more research, obtain more excellent bacterial strains, expand the scale, increase professionals, and improve manufacturing processes so that they can enter mass production.

But, what does this matter?

After obtaining this tube of liquid, taking this first step is a huge victory.

To be honest, although Dr. Yu has been working hard for several months, he is not very convinced of the so-called antibiotics that Su Xuezhi described to him at the beginning, which can cure sepsis, which is considered a terminal illness in contemporary times.

Until this day comes.

It was the end of May of this year, with sunshine and quietly penetrated into the glass of the laboratory.

Su Xuezhi wore gloves and gave intravenous injection of penicillin solution to several rabbits used for tests that had been injected with staphylococci a few days ago.

This intravenous injection was performed for two days.

The next day, the rabbit, who was already dying due to bacterial infection, miraculously recovered. Without exception, they all jumped around in the cage, very active.

Although he had psychological expectations, Dr. Yu was still shocked by the scene in front of him.

He closed his eyes, took a long breath, and murmured: "Xiao Su, I still can't believe that we have really made such a magical medicine! Do you know what this means? Many medical terminal illnesses will be effectively treated..."

Su Xuezhi smiled and said, "Yes, this is our goal. Our next work is to continue researching and improving the process so that mass production can be achieved in the near future, let it go out of the laboratory, and realize the true meaning of its release."

Dr. Yu was excited and nodded: "Yes, you are right! But we need to expand technicians, chemists, and a larger venue!"

"I will consider relocating the laboratory and moving to a more suitable place. As for the personnel, you have been in the industry for many years. If there are any one you think is suitable, please give me a list."

Dr. Yu agreed.

That night, Su Xuezhi made an appointment with Ding Chunshan and told him that he had plans to relocate the laboratory and needed a remote, safe and large enough place. He asked him if he could find a way to help find such a place.

Ding Chunshan agreed immediately, saying that he would do it immediately and tell her if there was any result. Then he said that there was something news here that he had to tell her.

"What's up?"

Ding Chunshan took out a letter: "The commander asked me to transfer yours."

Su Xuezhi returned to the dormitory and opened the letter.

The letter was indeed written by He Hanzhu, but in the letter, he did not have a word of Yu Mo. Apart from saying hello to her politely, he only said one thing.

He had previously received a letter from her mother Ye Yunjin. Ye Yunjin told him that after Zheng Longwang was injured last time, he had some physical problems and asked famous doctors all over, but the results were very little. Because he was inconvenient to disturb his daughter, he knew that many people he knew, so he wrote to him and asked him to help him find a Western doctor with excellent medical skills before going to see the situation. He contacted Rudolph. Rudolph rushed over and came back a few days ago and replied that the patient had become pericarditis due to trauma and had no cure. He had tried his best and was very sorry.

He Hanzhu finally said that he thought about it over and over again and felt that he should tell her the news.

Su Xuezhi finished reading the letter and was in a daze for a moment.

Pericarditis, myocarditis and other symptoms caused by traumatic infection are very common in wounded soldiers on the battlefield. Now, before the advent of penicillin, it was also a terminal illness, with a mortality rate of up to 70% or 80%. Whether an individual can finally get over it depends entirely on his own resistance and immunity.

She thought of the penicillin that had just been cultivated in the laboratory.

That is life-saving medicine.

King Zheng Long…

Su Xuezhi's eyes appeared in front of her eyes. She met her at the Fucheng Wharf before leaving last year.

She and the Shuihui master, who is known as Zheng Longwang, were like strangers. Not only did they have no feelings for each other, but the original Xuezhi left her with the impression of each other was still resisting and disliked.

However, she read the letter again, and when her eyes stayed on the part where Ye Yunjin wrote to him for a while, which was mentioned by He Hanzhu, she soon made a decision.

If there is no way to do this, it would be fine. Since I have already had the possibility, I always try my best to try it.

In any case, Ye Yunjin is her current mother.

She would actually ask He Hanzhu for help, and frankly said that this surprised Su Xuezhi. But it can also be seen how important this matter is in Ye Yunjin's heart.

But judging from the description in the letter, Zheng Longwang's body was already very weak, and with his age, it was impossible for him to travel here for long distances to receive treatment.

She could only rush back to the Xu Mansion with the medicine.

However,……

If she brings the medicine back, there will be a fatal problem of storage!

Penicillin is extremely unstable to heat. After extraction, unless it is used in a short period of time, it must be freeze-dried and turned into crystallization so as not to lose its effectiveness.

Freeze-drying equipment is very scarce now, and even in foreign countries, the best laboratories are hard to find.

When the laboratory was first established last year, she ordered a ship from a foreign company that operates imported medical equipment through Fu Mingcheng. The carrier was Fu's ship.

At that time, it was said that it would take at least half a year before the goods could arrive.

Su Xuezhi immediately got up, ran out to find the principal's assistant, took the office key, rushed into the office, and called the Fu family.

Fu Mingcheng had not yet rested at this time, and he was in the study. When the phone rang, he didn't look up. He picked up the microphone with one hand and held the pen in the other hand, and continued to line up the documents.

Suddenly, the tip of the pen stopped on the paper.

"Snow is here?"

He hesitated for a while, as if he was a little disbelief. He and the person on the other end of the phone line confirmed again, either thinking that he had heard it wrong or suspected that the other party was impersonating his name.

"It's me. Sorry to bother you so late."

It turned out to be her.

This was the first separate conversation between the two since he was assassinated and admitted to her hospital at the end of last year and she declined to confess to her.

Fu Mingcheng paused, then reacted and immediately said, "No, no, I haven't disturbed you! I haven't slept yet! Are you in trouble?"

After that day, he felt her intentional avoidance.

If it was okay, she wouldn't have suddenly come to her.

He thought to himself, with a little bitterness.

"Do you remember the cold-drying equipment I entrusted you to order from a foreign company when the laboratory was first established last year? At that time, it was said that it would not arrive in at least half a year. About two months ago, the foreign company informed me that they had ordered the equipment and entrusted the carrier. I knew that the time had not yet arrived, so I shouldn't have asked, but now the situation is special. Can you help me check when the ship will arrive?"

Fu Mingcheng immediately said: "Your cargo was jointly consigned by my ship and an foreign company freighter. The other party set out from Europe and took a long line. The entire sea route took half a year. I happened to check it a few days ago. This freighter had only passed the Cape of Good Hope. If you want to arrive at the port, even if everything goes well, it will take at least three or four months."
To be continued...