INSPIRATION

During the initial stage after team CPU_CHINA 2021 was established, we’ve brainstormed for several times to explore how synthetic biology may change the real world from every aspect of our society and lives.

Fig. 1 Brainstorming.

After multiple heated discussions, the current issue of excessive packaging in express industry captured our attention. In China, with the rapid development of e-commerce, express has gradually become an indispensable part in our daily life. Yet the convenience and efficiency that express delivery brought to us was inevitably accompanied by a large number of waste plastic packaging. These waste plastic packaging can not be easily recycled and reused like other packaging materials. And the white pollution problem they brought has seriously affected the living environment of human beings. With the passion for doing something to change the current situation, CPU_CHINA started from our surrounding environment and tried to carry out related investigations.

LISTEN TO THE WORLD

In sum, by conducting on-site investigations to learn about the production, transportation and disposal of express packaging waste, we specified our resolve of polyethylene degradation, whose settlement is of key importance for alleviating express waste pollution. We also received certain cautions to be paid attention to when designing and evaluating our project. In addition, through summarizing current situations of PE recycling industry and talking to practitioners in the field, we discovered the potential application of our project as a potent pollutant cleanser and resource regenerator.

CHAPTER 1. EXPRESS DEPOSITORIES

In order to explore the story behind discarded express packaging, we focused on their origin by going to the site for acquiring first hand information. The first location that came into our mind was the Cai Niao Courier Station in our campus.

Fig. 2 Interviewing the staff of the Cai Niao Courier Station.

We interviewed the staff of the Cai Niao Station in China Pharmaceutical University. According to their knowledge, the amount of express delivery and plastic packaging consumed solely by this very station in our school was already considerable. Normally, there are about 7000 received packages at the station per day. On average, every student of the school receives 4.5 packages per week, and this number will increase significantly during sales promotion of many e-commerce platforms. In addition, logistics companies and merchants tend to apply excessive packaging in order to ensure the safety or improve the exquisiteness of the goods before sending them out. All of these factors contributed to the accumulation of discarded packaging waste, which needs to be cleaned up by the staffs for many times on a daily basis.

Fig. 3 The person who took the packages.

The data and records provided by the staff during this interview revealed to us the shocking volume of express delivery industry, and the accompanying packaging waste, which strongly proved the urgency of this issue. This prompted us to conduct a more veritable research outside the campus to acquire a more comprehensive and realistic understanding, as well as to determine the specific but crucial problem we should tackle. Therefore, the next stop we visited were several residential areas in Nanjing. Similar to the situation in our campus, we found that there were many discarded plastic packaging in the express depositories of the community. After randomly interviewing some residents, we learned the following things:

1. The development of online shopping in China has led to a boom in the express delivery industry, which clearly benefits everyone. A community resident who was signing for packages told us that everything she needed in daily life can be mostly bought online, thus saving her time of shopping in grocery stores and supermarkets for other meaningful purposes. The storage racks full of parcels in the express depositories also illustrated the importance of express delivery in the lives of Chinese people.

2. Large numbers of packages can bring not only convenience, but also waste. The staff at the community express depository said that in order to ensure the integrity and safety of goods during their transportation, apart from commonly applied paper boxes as a container of goods, the express companies also have to use plastic packaging materials such as adhesive tapes and inflatable damping bags to seal the package and protect the goods. By the time these packages reached to consumers, unlike the recyclable paper boxes, these plastic packaging materials would be thrown away instantly and turned into garbage--this was a brand new fact that was extremely important. Some other residents who came to pick up the packages also informed us about the inconvenience caused by overpacked plastics on their parcels.

   

Fig. 4 Talking with residents.

The situations and findings in the residential areas were similar to what we've discovered in the campus. As a result, we realized that without an appropriate treatment, these single-used plastic waste are bound to cause serious consumption of resources, as well as the environmental pollution.

Fig. 5 A lot of plastic waste.

Fig. 6 Garbage truck.

 

Feedback:

In light of the acquired findings from the two preliminary visits, we realized that the accumulation of plastic packaging waste had been a problem that requires urgent response and attention. Therefore, bearing the values of sustainable development in mind, members of CPU_CHINA 2021 began to conduct literature investigation and discussions, in search of an potential innovative solution towards this issue, with the hope that we can solve plastic pollution nowadays. During this process, we got to know that the main composition of plastic packaging waste was polyethylene (PE), a type of widely used polymer material mainly consisting of carbon and hydrogen, making it difficult to be degraded under natural conditions. Thus, we became determined to develop a new type of PE degradation method that can effectively accelerate the break down of PE.

Fig. 7 Lively discussion among members.

Fig. 8 Discussing project.

Meanwhile, since we were trying to figure out a new solution on plastic waste treatment, it is also of vital importance to know about the current plastic disposal situations to help us precisely modify our project. Therefore, eager to have a more in-depth understanding of the city's waste plastic treatment system, we made a trip to the garbage disposal transit station in Jiangning High-tech District for on-site investigation.

 

CHAPTER 2. GARBAGE TRANSIT STATION

This station is the centralized disposal point of household waste produced in the district. The station staff told us that household waste from the communities will be concentrated in the district-level garbage processing transit station, where the recyclable materials will be sorted out for recycling; the kitchen waste will be sent to special processing device for resource reclamation, generating organic fertilizer as the final product; and other waste will be directly loaded to the garbage transfer trucks for transportation to garbage incineration plants or landfills.

Fig. 9 Interviewing the staff of the garbage transit station.

Fig. 10 The staff is disinfecting the garbage truck.

As for our survey object, we learned from this trip that PE belongs to other waste. Its disposal profile showed that part of it will be recycled and reused by professional companies, but the other portions that cannot be recycled will be uniformly transported to incineration plants or landfills in the suburbs.

Fig. 11 The transportation flow of waste plastic.

Therefore, to close the loop of the journey of disposed plastic waste, we decided to conduct further interview to plastic recycling enterprises, and to make visits to garbage disposal plants.

CHAPTER 3. THE END OF DISCARDED PLASTICS

Plastic recycling enterprise:

Lanzhou Jintudi Plastic Product Co. Ltd

Lanzhou Jintudi Plastic Product Company Limited is a large entity enterprise which specializes in recycling waste plastic into new materials, such as agricultural mulching film, for production and transaction. We contacted the chief manager of this enterprise, Ms. Sun, through team DUT_China, to learn about the existing PE products and the recycling status of PE.

Fig. 12 We met Ms. Sun and her student, Mr. Liu of Lanzhou Jintudi Plastic Product Co. Ltd with team DUT_China.

1. Ms. Sun introduced us to the technological process of plastic recycling.

   She told us that China's plastic recycling market only began to develop in recent years. The existing technology is not particularly mature, thus the requirements on waste plastic as raw materials for recycle are relatively high. However, the sources of waste plastics are complex, and they often mixed with impurities such as fabrics, rubber, metals, and silts, making them difficult to be processed for now. So the fact is, there are currently not many types of plastic can be recycled and reused. The remaining portion can only be landfilled or incinerated. There is no doubt that the plastic recycling market has huge development potential in the future, but nowadays the proportion of plastic that can be recycled is still small, which requires the joint efforts of academia and industry to improve this situation.

2. With increasing emphasis on sustainable development by government, numerous enterprises have begun to develop degradable plastic pipelines. However, they encountered many realistic factors, such as high cost of material, rigorous degradation condition, incomplete degradation and so on. There is still a long way to go for biodegradable plastics to be used on a much wider scale.

3. As a result, our aim of trying to tackle the issue of unrecyclable PE plastic pollution was highly recognized by Ms. Sun. She affirmed the practical significance of our project, but she also pointed out for us that if we want to evaluate the plastic-degrading efficacy of our system, we must pay attention to the additives in the selected plastic samples for the reason that they might affect the experimental outcome. Also, she suggested that as we carried on designing and modifying our project, there are many governmental regulations and national standards about plastic degradation evaluation that would benefit our design, and we should look them up carefully.

Feedback:

We learned from the interview that due to various realistic factors, both the plastic recycling industry and the bio-degradable plastic production industry have their own advantages to occupy a portion of market share, and their disadvantages that limit the market share from expanding. This phenomenon enlightened us that we should also evaluate the advantages and disadvantages of our project that would define our share of market, in order to determine the implementation of our product. As a result, we hoped to seek more guidance and comments on our project from practitioners in the plastic industry, which prompted us to attend relative industry exhibition or market development forum, where we would have the chance to meet more stakeholders for feedback.

At the same time, we must pay attention to national standards when verifying the plastic degradation efficiency of our system. In response to the advice provided by Ms. Sun, we made adjustments on our experimental design regarding the selection of plastic samples and the evaluation of plastic degradation by adding multiple means of instrumental analysis approach to evaluate the degradation of PE more comprehensively.

 

Plastic disposal plant:

Our last stop is the garbage treatment plant located in Jiaozishan. The unrecyclable PE, together with other urban garbage, were collected by the garbage disposal transit stations in all districts and counties and were transported to here, waiting for their final destinies.

With the increase of the urban population and the improvement of people's living standards, the output of municipal solid waste is also increasing. According to statistics, two-thirds of China's 668 cities are surrounded by garbage. The total land area of garbage storage in the country has reached 500 square kilometers, and one-quarter of the cities have developed to a stage where no suitable land is available for storage. China's municipal waste is growing at an annual rate of 8% to 10%, reaching 340 million tons by 2020.

As mentioned before, the unrecyclable PE waste is transported to the landfill for sanitary burial. Such a treatment method makes the degradation of municipal solid waste very slow, not to mention the strategy of accelerating their degradation is relatively scarce. Thus, these accumulated waste will inevitably lead to a huge impact on the environment for a long time.

Fig. 13 Interviewing the staff of the plastic disposal plant.

Fig. 14 Watching the scale video of the landfill site together with the staff.

The technicians managing the landfill told us that the natural degradation process of municipal waste is accompanied by occurrence of multiple physical, chemical and biological reactions in reality. During this process, microorganisms may play a leading role in biodegradation of the waste. Therefore, we suggest that applying biological factors to accelerate the disappearance of plastics in landfills should be an ideal approach to alleviate the serious white pollution.

SUMMARY

We shared the collective information with other members of the team. By integrating results of preliminary literature investigations and feedback from field researches, a consensus was established in the whole team that microbes and their associate enzymes can play an important role in promoting degradation of many types of pollutants, including plastic wastes. So our team further skimmed through a lot of extra literatures and databases hoping to discover agents that have the potential to degrade PE. After putting up extensive efforts, we discovered manganese peroxidase (MnP), a lignin peroxidase derived from the white-rot fungus Phanerochaete chrysosporium. It has been reported in literature that MnP secreted by the fungus still has a significant degradation efficiency when applied on the PE film alone. Therefore, we decided to focus on this very enzyme and eventually designed a polyethylene degradation system based on three functional protein and two connect systems. We named it "Polyethylene Degradist", or PEDe.

For details, please see Design.

At the same time, based on the design of our PE-degrading system, we have clarified our brief product positioning. Our product, the PEDe., can be used to solve the pollution of the existing enormous amount of discarded PE waste towards the soil and water, as well as to improve the resource utilization rate so that the existing landfills can maximize their effectiveness. Therefore, our project can provide a positive influence for the environment. CPU_CHINA hopes that our efforts can help the world to recover from the burden of white pollutions.

MADE OUR VOICE HEARD

As the theme and design of our PE-degrading system were settled, we proceeded to transform concepts into entities. During this process, stakeholders, practitioners and experts were met, consulted or interviewed in order to receive guidance that helped to determine market positioning of our product, raise public awareness of waste sorting, tackle problems of verifying project feasibility, and most importantly, answer the question of how would our product be implemented in the real world.

EXPERTS

click number for more details

INDUSTRY EXHIBITION & MARKET DEVELOPMENT FORUM

In order to further explore the market system and determine the business model of our product, we participated in the 2021 China (Nanjing) Plastics Industry Exhibition & Biodegradable Plastics Chemical Technology and Market Development Forum held in Nanjing International Exhibition Center on June 17, 2021. On this exhibition, we interviewed stakeholders from Wujiang Green Forest Resources Recycling Company Limited and SANER International.

Fig. 15 Industry Exhibition & Market Development Forum visit card.

Wujiang Green Forest Resources Recycling Company Limited

Fig. 16 Taking photo with Ms. Lin.

Interviewee: Ms. Lin, General Manager.

Enterprise attributes: Recycle and utilization of renewable resources

Interview content:

1. A Brief introduction of the main business of the enterprise.

The enterprise recycles scraps, defective products generated in the factory and daily necessities (cosmetics, toiletries). They set up sorting points and deep-processing plants in China and Japan to classify and recycle the collected plastic waste. With the help of physical, chemical and other kinds of methods, plastic waste is transformed into new plastic particles.

2. The source of plastic waste.

Most of the recycled plastic waste comes from China. The current recycling situation is relatively good. The recyclable plastic waste will be purchased directly from plastic manufactories or companies. Compared with recycling from the garbage disposal station, it is more efficient and more professional. A part of the domestic waste collected by the recycling station can also be used, but specific evaluation and classification are required.

3. The prospects of the plastics market.

According to the current orientation of policies in China, and the development trend of global environmental protection, the future plastics market will definitely develop towards the direction of degradability and recycling. Degradable plastics can solve the problem of plastic pollution from the source, while plastic recycling uses different technologies to make recycled discarded plastics into plastic particles for reuse, which can create greater economic value. But there is still a long way to go for the ideal future.

4. Advice on our project of plastic degradation.

Mr. Lin expressed appreciation on our ideas, but he also pointed out that we must pay attention to practical issues, such as cost and budgets, as well as the project's possibility to be applied to reality, etc. He reminded us that the transformation of technology into products is a difficult process, thus we should contact various stakeholders for suggestions, and analyze the economic effects that can be created by our products.

 

SANER International

Fig. 17 Taking photo with Manager Shen.

Interviewee: Manager Shen

Enterprise attributes: Recycling and reusing of plastic

Interview content:

1. Main business of the enterprise.

The main business of the company is to recycle waste plastic and use them to produce new plastic products through crushing, washing, and pelletizing. But unlike other companies, the main raw materials of this company are plastics in household waste.

2. The main source of raw materials.

Most of them come from Europe, America, Japan and other regions. Only a small amount of them comes from China. Because the foreign waste classification system is more mature and the plastic recycling market is also more developed, the recycling work is easier. China's garbage classification started later and there are still many areas that need to be improved.

 

Summary

1. Through communication with stakeholders, based on their feedback, we learned that besides technology itself, we also need to pay attention to the process of transforming technology into products and assess the economic benefits of products. Therefore, after that, we made a business plan for PEDe. to analyze the market or competition and formulate marketing strategies.

   For details, please see Entrepreneurship.

2. We were reminded that the domestic waste classification is not yet mature enough, as it is the reason why the raw materials for plastic recycling come from foreign regions. Therefore, we decided to use the iGEM platform to promote the importance of waste sorting to the masses, hoping to raise public awareness of waste sorting. Based on this, we have opened a waste sorting publicity activity.

   For details, please see Education.

 

ENVIRONMENTAL PROTECTION ONLINE

Fig. 18 Taking photo with Manager Wang.

Interviewee: Manager Wang

Enterprise attributes: "Internet Plus" service platform for environmental protection industry

Interview content:

1. Main business of the enterprise.

The main purpose of this enterprise is to build an information exchange platform for green companies, such as degradable plastic production companies and plastic recycling companies, to display their marketing and purchasing information. Also, the platform promotes environmental protection technologies, as well as pollution control methods on a daily basis. There are websites and apps ready for use.

2. Advice on our project of plastic degradation.

There are many companies in this area that they have cooperated with. From an academic point of view, our idea and technology are with high value and significance, which is awesome and worth of praise. When these technologies become more mature, Environmental Protection Online is willing to cooperate with CPU_CHINA to further promote our products and concepts.

3. Suggestions for the promotion of the CPU_CHINA project

Nowadays, young people are becoming more accustomed to receiving information from the Internet, without the rapid development of online social media not could be true. Therefore, CPU_CHINA can make use of Weibo, Bilibili, YouTube and other online platforms to expand influence when promoting our project. In addition, we can implement some more interesting ways to attract public attentions.

 

Summary:

Members of human practices gained a lot from this conversation. Based on the inspiration we acquired, CPU_CHINA set up official accounts on major social platforms, planned an art exhibition named Meddy: Relight My Star and produced comic strips. All of these have won the favor of the public and provided great help for the promotion of our project.

For details, please see Education and Meddy .

 

ECOLOGY ENVIRONMENT BUREAU OF NANJING

After determining the project positioning and related technologies, we contacted the staff of Ecology Environment Bureau of Nanjing by phone and consulted their opinions on our project.

The Ecology Environment Bureau is a functional organization of the local government in charge of environmental protection.

Fig. 19 Ecology Environment Bureau of Nanjing.

(The marketization of public services does not mean the transfer of government 's responsibility. So the Ecology Environment Bureau is still responsible for supervision and management.)

After inquiring relevant laws and regulations, we found that the government has paid great attention to the phenomenon of excessive packaging in the express industry and has issued regulations to restrict it. The Ecology Environment Bureau of Nanjing expressed support for our project and advised us to focus on the practical meaning of this project. The staff suggested that we try to advertise the project for investment through various ways, and transform the project into products when the technology is mature. At the same time, we should determine the product orientation for subsequent promotion. They also reminded us to focus on risk assessment and control as the project proceed.

PRACTISE IN REALITY

END USER

The main end users of our product are garbage disposal plants and government environmental protection departments, supplemented by non-profit organizations, ecological restoration companies, and biotechnology companies.

HOW TO USE

Our entire system can be distributed to users in the form of protein/nucleic acid freeze-dried powder. A set of product includes four types of protein freeze-dried powders and four types of nucleic acid freeze-dried powders. After receiving the product, the user only needs to re-dissolve the powder into designated solutions, and assemble the entire degradation system in a few simple steps as instructed. Subsequently, the assembled system can be directly applied to the surface of PE. By adding the required substrate solution, the degradation reactions will be activated.

HOW TO IMPLEMENT

Based on the novelty of our plastic degradation product, PEDe. will start promoting from a small scale. Taking the Jiaozishan Landfill, Tianjingwa Landfill, and Shuige Landfill in Nanjing as examples, the construction of the three landfills have played a vital role in solving domestic garbage outlet and realizing harmless waste treatment for the city. We planned to set the three Nanjing municipal landfills as the starting point of our product, to explore the commercialization potential of PEDe.. Through seeking cooperation with the government, biotechnology companies and non-profit organizations, a transaction can be concluded with the landfill to degrade the collected PE plastic waste. And by gradually expanding the product market, we hope to realize a comprehensive development in many provinces and cities across the country, and finally promote out product to the world. Entrepreneurship

FUTURE

Comprehensive ecological restoration

Based on the principle, the final product of this project has the potential of degrading polycyclic aromatic hydrocarbons, azo dye and other organic pollutants in addition to PE, which are also the causes of water and soil pollution. Therefore, PEDe. can be used to explore more possibilities in the field of ecological restoration beyond degrading PE, such as cooperating with ecological restoration companies to help them complete the comprehensive management of the ecological environment.

"Nowadays, the Chinese government pays more attention to the negative impact on the environment during the process of economic development, and continues to increase its efforts in environmental governance. The 19th National Congress of the Communist Party of China clearly stated that efforts should be made to solve environmental problems, and the government has issued relevant policies to promote water and soil conservation, urban ecological restoration, land management, river, lake and wetland protection, marine ecological protection and other fields. With the strong support of national policies and the rapid growth of market demand, the ecological restoration industry has developed rapidly and the market scale has continued to expand. From 2015 to 2019, the scale of fixed asset investment in China's ecological protection and environmental governance industry has gradually increased, with an average annual compound growth rate of 21.27%, and the market size is expected to reach 956.3 billion yuan in 2021. At the same time, traditional landscaping companies have been seeking business breakthroughs and transformations. Their business structure has clearly shifted to the field of ecological protection and restoration; enterprises in the industry are gradually developing towards comprehensive ecological restoration. The future of the ecological restoration industry has unlimited potential!"

Advantages of the connect system

Although the function of the final product of this project focuses on using the synergy of functional proteins to accelerate the green degradation of PE plastic, the CRISPR/dCas9 anchoring system used to connect functional proteins has quite flexible modularity and programmability. That is, through the special sequence design of the double-stranded DNA, the spacing, number and arrangement of the binding sites of the dCas9: sgRNA complex on the chain can be customized. Combining with the SpyCatcher/SpyTag connection system, the anchor of an ordered assay of functional proteins can be achieved.

Studies have shown that using this system to connect enzymes on specific metabolic pathways in series can effectively accelerate the rate of conversion of the original substrate into the target product, and greatly increase the yield of the target product. That is to say, the design of the double connection system, combined with diversified functional proteins or enzymes, complexes with distinct function can be generated, enabling them to play a role in many known or potential fields, such as industrial production, basic scientific research, analysis and testing!