We get to know our helpful advisor Boxiang in one EPIC VCL workshop.( See details in EPIC VCL )

Boxiang is CTO and co-founder of Links-Spider Technology Co., Ltd. Boxiang gave us inspiration of introducing directed evolution into our project design. Thanks to his interesting ideas offered to us，which leads to a huge highlight of using directed evolution into our TPE project. ( See details in Engineer.)

During iGEM, Links-Spider Technology Co., Ltd has provided a lot of help in our experimental process, and the project of LINKS_China team they leaded last year also applied the biological production process of Tyrian purple. In terms of the fermentation production of Tyrian purple, LINKS_China provides us with Part Fre-SttH (BBa_K4011003) and Part TnaA-FL-FMO (BBa_K4011004), simplifying the construction of our metabolic pathway. In addition, we have determined the most suitable induction conditions for various enzyme proteins through communication with LINKS_China, and constructed the optimal fermentation system for the production of Tyrian purple. In terms of the directional evolution of TrpR, LINKS_China provided us with Part sfGFP (BBa_I746916), and Links-Spider Technology Co., Ltd spnsored us a to synthesize three plasmids of part pTrpR, part pNEG and part pPOS and establish a mutant library of our trpR through fixed-point saturation mutations fastly by a startup company named Xinsu Technology (芯宿科技 in Chinese).

Thank you, Links-Spider Technology Co., Ltd !

We collaborated with the 2021 iGEM team LINKS_China team and built a strong partnership in many ways, where the SUSTech_Shenzhen modeling team interacted with Patrick from the LINKS_China modeling team and benefited greatly. During the exchange with the LINKS team, we discussed modeling ideas and methods, and thought about the same model in a diffuse way.

Aug to Oct 2022

Through online meetings, we also had 3 exchanges with Dr. Honghao Su from Earlham Institute, who has rich biological knowledge and modeling experience and has guided several iGEM teams in modeling. The difficult meeting across three countries with time difference finally paid off. Several exchanges with him finally determined the direction and means of our modeling, which eventually led to the improvement of our model.

On March 6th, Yuhan Bao, project leader of Human Practices at iGEM, and the iGEM team of Shenzhen University exchanged their understanding of Human Practices through video conference.

Yuhan Bao proposed that human practices need to pay attention to responsible innovation in the Chinese context and be suitable for the system with Chinese characteristics. Human Practices content is not necessarily project-linked, emphasizing feedback and engagement, particularly with regard to social issues. Human Practices work is more important to startups, and it is about market competition and screening. Human Practices work enables the transformation of scientific and technological achievements, and the output becomes more diverse from a single paper. Anlan Zhao understood Human Practices as: in a broad sense, it is a work that promotes social development and realizes social value, while in a narrow sense, it is to improve experiments and activities through multiple ways. Ruiyue Chen's understanding of Human Practices can be summarized into three verbs: investigation, improvement, and improvement. Rongsong Ling views the work of Human Practices from the perspective of a start-up company, and he regards the work of Human Practices as a roadshow to the public, attract investors, and help the project land. Siyang Yu’s understanding of Human Practices is to realize the closed loop between the project and the public.

After exchanging our understanding of Human Practices, we also discussed the places of confusion. Xushan Zhang asked: Does Human Practices work introduce projects to the society or get feedback from the society? Bingru Feng believes that there is both, and Rongsong Ling believes that synthetic biology is more like engineering than biology, and it needs to come from the masses to the masses. Taking gene therapy as an example, society has caused a sensation due to medical malpractice caused by gene therapy, and the significance of Human Practices is to prevent such accidents. For this question, Yuhan Bao pointed out: the public includes professionals; Public oversight but implementation is difficult; Scientific research eventually has to get out of the lab; The actual implementation of the measures needs to be implemented and refined.

We then discussed how human practices work in the context of a society with Chinese characteristics, what issues it faces, how to carry out responsible innovation in the Chinese context, and whether there are other better ways out when activities are affected by policies or hindered by the review process.

Through this exchange, we gained a deeper understanding of Human Practices and provided us with ideas and priorities for designing Human Practices activities. And we get to know how to value a Human Practice project, which help us a lot when designing for Human Practice activities .

Thank you, Yuhan!

We are aiming to use bioengineered bacteria to produce dyes for fabric dyeing, hoping to avoid environmental pollution caused by the production and use of industrial dyes. To this end, we contacted Zhongying Wang , associate professor from the School of Environment, SUSTech. And he provided his advice and guidance on our project in terms of pollution avoidance.

Professor Wang pointed out that compared with chemical synthetic dyes, biosynthetic dyes have less toxicity of by-products in the production process, which is our advantage. At the same time, for the idea of secondary utilization of recycling enzymes we proposed, Professor Wang said that the actual production is more concerned about the cost, if the recovery cost is higher than the emission cost, the manufacturer will not choose to recycle. But Professor Wang also mentioned that if we do not consider the cost, the use of biological treatment methods to degrade waste is a very meaningful idea and can be used as a highlight of the project.

Introduction

Chinese natural dyeing technique has a long history and is an important part of Chinese civilization. People use natural plants and minerals to create colors. Plant dyeing has been the mainstream of ancient garment dyeing in China for thousands of years. This technology has rich connotation and theoretical support. In order to deeply understand this technology and improve it, we contacted the representative inheritor of this technique, senior engineer Huang ronghua, to consult him about plant dyeing.

Feedback

1. The resources of the earth are limited. Compared with chemical dyes that are difficult to dispose of its pollute, it is desirable for natural dyes to return to the market. However, natural dyes also have the disadvantage of high cost, which cannot completely replace chemical fuels. It is more suitable for the dyeing of close-fitting textiles such as underwear and home textiles.

2. Compared with chemical dyes, natural plant dyeing does not need to consider the problem of color fastness. It can achieve a good color fixation effect through the compatibility of different dyes, so it avoids the use of color fixing agents that will cause pollution.

3. At present, large-scale industrial production of vegetable dyes has been carried out, but relevant safety standards are still being formulated. It has high safety, but it needs to artificially exclude plants harmful to human body

4. Plant dyeing is only suitable for natural fabrics, such as natural fibers, cotton, silk, wool, modal, Tencel, etc. But cannot be applied to artificial fibers such as polyester fibers. He is in favor of producing dyes through synthetic biology, which is a very good direction. Synthetic biology is also an inevitable trend to produce natural dyes in a large-scale, sustainable, and controllable way in the next step, which is very prospective and practical.

Problems we need to solve: how to increase color depth and levelling property, better permeability, higher color fastness, and stability (Current problems of synthetic biological dyes: color fastness is too poor at present, which is difficult to use; textiles need to be washed at least 50 times and not fade). The fibers on different fabrics are different, and the same dye is difficult to show the same color on different fabrics.

Plant dyeing has been passed down in China for thousands of years, but making natural dyes can not be limited by it. It is necessary to adapt to the development of the times and integrate traditional culture into modern people's daily life, so that the integration of ancient and modern can go further

After investigating lots of corresponding laws about dying and environmental protection, we found there were still many details that we didn’t know. Therefore, we determined to contact the dying factory to do some further research about practical dying methods and how they treated the contaminant.

In the beginning, we found a research institute that used coli-bacillus to synthesize indigo and used the product to d the jeans. We sent an email to them and asked if they could give some advice on our team project and introduced some background knowledge about the whole dying market. Unfortunately, because the institute didn’t have sites near Shenzhen, they cound’t give advice to us directly.

After that, we turned our views to the institute or factory near Shenzhen. After contacting several dying factories, we finally found out a proper factory near Jiangmen, Guangdong province, Hetang Sai Xinglong Bleaching and Dyeing Ltd.

Arriving at the factory, we visited the production workshops for spinning, grinding, rolling, and dyeing to understand the actual process of dyeing textiles, learned how the factory facilities work and realized the difference between actual industrial production conditions and laboratory conditions. Before we investigated, we thought that the dying process was quite simple and full of disadvantages compared to the latest research. The complexity, however, really surprised us and we found issues that we haven’t focused on before. In the factory, they paid great attention to the stability and efficiency of the dying methods. They needed a method, that gives out a large output even in diverse conditions. In the factory, we found the environmental conditions were not stable. The temperature, for example, could reach 40 in the summer and as cold as 0 in winter. The stability of the dying method becomes extremely important. This provided us with a direction to think about for subsequent improvement of the project to make it more applicable to actual production. We found that Between our research and practical use in the industry, we still had a long way to go.

We also investigated the sewage treatment system, and the scale of the devices really shocked us. They used four pools to do step-precipitate sewage. In different pools, there was a dramatic difference in the wastewater quality. They used microorganisms to digest the waste in the pool.

The advantages were obvious, cheap, and high-efficient. Besides, their backup awareness was critical in engineering design. No matter the water supply system or the sewage treatment system, they always had a plan B to measure unexpected situations. The water supply system had two pools, one for daily use, and the other for standby. What the most interesting is that they used an ingenious method to detect the quality of water resources, they raised some fish in it! This design was fantastic and useful because they used the fish as a dynamic environmental detector without disturbing the water input. For sewage treatment methods, they had a chemical sewage pool to measure the situation when the biological sewage pool breaks down, the chemical pool, however, wasn’t used in usual conditions.

All of these experiences gave us a general idea of how the factory worked. And these experiences, on the other hand, reminded us to reconsider the setting and goals of our experiments.

Exploration from scratch

In order to understand the current dyeing technology in the market, we contacted the person in charge of Suining Qunkang printing and dyeing limited liability company located in Sichuan Province, asked him about the steps of dyeing process used by most of the factories at present, and made a detailed investigation on each specific step and a variety of specific dyeing methods.

Information we got

Fabric treatment process before dyeing: Turning cloth - sewing head - scouring - singeing - mercerizing
The process of dyeing process: priming - pre drying - drying - color development (fixation) - washing - drying – arrangement after finishing

What are the wastes and pollution generated in the existing dyeing process?
There are many pollution sources in the existing cotton dyeing process: dyes that have not been fully absorbed, additives in the dyes, and inorganic substances that help the dyes to dye, such as caustic soda, soda ash, insurance powder, etc.

What factors need to be considered in our project:
whether the dye can be dyed, the dyeing conditions, the color fastness, the color spectrum of the dye, the determination of the dyeing conditions to determine the process flow and supporting equipment for large-scale production.

In the investigation of ancient Chinese dyeing methods, we unexpectedly found that even after thousands of years of precipitation, the color of clothes was still bright. On the contrary, many of the clothes we buy now will fade after repeated washing. So we further explored the dyeing process of ancient clothing and found that plant dyeing is an environmentally friendly and high-quality dyeing method.

Plant dyeing refers to a method of dyeing objects by extracting pigments from various naturally growing plants containing pigments. It refers to a process in which natural dyes are used for dyeing, and natural dyes obtained from nature are used for dyeing products without or rarely using chemical additives in the dyeing process. The history of human use of natural dyes can be traced back to the Paleolithic age 100000 years ago. At that time, mountaintop cave people used mineral pigments to dye red necklaces. The use of natural substances to dye colorful colors reflects the earliest pursuit of beauty. However, with the development of the chemical industry, cheap and easy to produce chemical dyes quickly seize the market, resulting in natural dyes being gradually forgotten by the people. As the world pays more attention to environmental protection and the demand for clothing quality rises, the market demand for natural dyes becomes more and more urgent. In 2022, SUSTech_Shenzhen hopes to improve the shortcomings of difficult access and high cost of natural dyes, and use bacteria to produce safe, harmless and environmentally friendly high-quality textile dyes through synthetic biology.

At last, we summarized to an Investigation report on dyeing method after Q&A with dyeing factory.

Investigation report on dyeing method

1、Traditional dyeing technology and process
Before the invention of chemical dyes, ancient China used a variety of plants as raw materials for dyeing. Different plants, together with different mordants and fabrics, could produce different colors. Plant dyes are derived from natural plants. The dyed clothes are not only natural and pollution-free, but also stable, with high color fastness, and even have the efficacy of sterilization and anti-inflammatory of plants themselves. There are many different coloring techniques in traditional Chinese plant dyeing, such as raw leaf dyeing, which directly uses fresh plants to dye, and decocting dyeing, which needs to increase the temperature through decocting to make the pigment adhere to the clothes better.

The tie-dye elements that are very popular in the clothing market at present also come from the ancient tie-dye technology in ancient China. In Yunnan, China, the Bai people will hand weave white cotton and earth cloth, then create patterns, and dye beautiful fabrics through the manual flower tying method of sewing and binding. The main steps of tie dyeing include painting patterns, wringing, soaking, dyeing cloth, cooking, drying, stripping, rinsing, and cloth grinding. Among them, there are mainly two processes of tying flowers and immersion dyeing. The technical key is the wringing technique and dyeing skills. Batik is also an ancient traditional hand dyeing method. It first uses a wax knife to dip the melted wax into the cloth and then uses indigo to dye, and then uses water to boil and dewax to show the pattern. The dye penetrates the cloth through the cracks of the wax, leaving naturally formed ice cracks on it, adding artistry and interest.

Natural dyeing needs to start from planting plants, and the cost and uncontrollability are higher than those of chemical dyes. However, its safety and environmental protection are far higher than chemical dyes, so it is favored by consumers in the high-end market.

2.Jig dyeing
Jig dyeing, the method of fabric dyeing on a roll dyeing machine. The fabric is wound on one roller of the jigger in a flat width, and then wound to another roller through the dyeing bath. After the winding, it is repeated in reverse until the fabric is uniformly dyed with the desired color. It is an intermittent production method, suitable for multi variety and small batch production. At present, the printing and dyeing industry is developing rapidly. At the same time of large-scale orders, there are also many relatively small orders. The winding dyeing cylinder plays a certain role in the replenishment and repair of small-scale orders or large-scale orders, which not only improves efficiency but also reduces factory costs.

3.Beck dyeing
Beck dyeing is a method of fabric coloring in modern industrial mass production. The modern dyeing tank has the functions of heating and stirring. It is an electrically controlled equipment with digital control. It is composed of the cylinder body, water supply and drainage system, dye and chemical addition system, heat exchange system and power system. The cylinder body is used to hold the dyeing liquid and dip the dyed fabric. The water supply and drainage system is used for quantitative water addition and drainage. The dyestuff and chemical additive system is used for dissolving, dispersing and injecting dyes and auxiliaries into the cylinder block. The function of the heat exchange system is to circulate or directly heat the dye solution in the cylinder. The power system makes the fabric run and dye evenly. Once, the traditional printing and dyeing process needed to produce a large amount of printing and dyeing sewage and waste gas through high temperature and high pressure, which would pollute the environment.