The WHHS-China team is deeply aware that glyphosate, as a widely used herbicide, is particularly important in the current agricultural development. Initially, we focused on the problem of glyphosate residues in tea. As the project progresses, we hope to promote the green and sustainable development of agriculture from production to consumption. This is not only about food safety, but also about the protection of the ecological environment. We hope to provide consumers with healthier and safer agricultural products. Our goal is to find effective solutions and promote the sustainable transformation of agriculture through scientific research and technological innovation.

Our overall goal of integrated human practice is to collect various feedbacks by interviewing stakeholders, conducting surveys, and actively participating in relevant current events. Based on the information obtained from these interactions, we will adjust the project accordingly to ensure that it better meets actual needs and challenges. This dynamic feedback mechanism will help improve the effectiveness and impact of the project.

At the beginning, our team visited the tea plantations in Wuyishan, where we learned during the tea-picking process that herbicide residue is a major issue troubling tea plantations. This not only affects tea exports but also concerns the sustainable development of the plantations. Additionally, we discovered that the herbicides currently in use, such as glyphosate, lack national standard detection methods.

The common physical and chemical methods for detecting and degrading glyphosate are complex to operate and costly. After group discussions, we decided to explore the possibility of using microorganisms to degrade glyphosate. Biological degradation methods are not only cost-effective but also effectively reduce environmental pollution, providing a greener and more sustainable solution for tea plantations and other agricultural production. This direction injects new energy into the advancement of our project.

Later, we visited the Baiquan Tea Garden in Wuhan, where we learned about the widespread use of glyphosate. However, due to the unique nature of tea leaves, they cannot withstand excessive washing during the production process, leaving plantation managers with the challenge of effectively dealing with glyphosate residues. Our team decided to focus on researching and addressing the issue of herbicide residues in tea plantations.

We visited a pesticide store to gain a deeper understanding of the widespread use of glyphosate, a common herbicide. It is extensively applied in various agricultural production fields, such as tea plantations, mulberry orchards, and fruit orchards, and is favored by farmers for its efficiency and cost-effectiveness. Through discussions with the store staff, we further recognized the importance of glyphosate in increasing crop yields and controlling weeds, but at the same time, we became aware of the potential impact its residue could have on the environment and food safety.

We visited Luojia Mountain and spoke with a sanitation worker who was weeding. He told us that he uses glyphosate herbicide but is unaware of its potential hazards. He admitted that his main concern is whether the herbicide can effectively kill weeds, without considering the long-term impact of the incomplete degradation of the chemical. He also mentioned that the short-term effect of the herbicide is their top priority, and as long as the benefits outweigh the risks, they consider it acceptable.

During our conversation with the sanitation worker, we provided scientific education about the hazards of glyphosate, explaining in detail its potential impact on the environment and human health. We suggested that he reduce the frequency of glyphosate use and consider establishing a usage cycle to minimize chemical accumulation and its negative effects on the ecosystem. This way, weeds can still be effectively managed while also contributing to the protection of the environment and his own health.

This interaction made us realize that in addition to developing effective technologies to degrade pesticides, there is a need to raise public awareness of environmental protection and pesticide usage. Through education and outreach, we hope to promote more responsible usage habits and better safeguard the environment we depend on.

Our team visited a flower and landscape nursery to learn about the use of herbicides in horticulture and conducted interviews with several nursery managers. The managers generally reported that due to the complexity of dealing with pesticide residues, they often rely on manual weeding. However, this method is time-consuming and labor-intensive, resulting in an excessive workload and affecting overall efficiency.

During our discussions, we introduced them to the concept of using microbial technology to address glyphosate residue. The managers expressed strong support for this idea, believing that if our product can effectively solve the herbicide residue issue, it could significantly reduce the amount of manual weeding required. This positive feedback has further strengthened our confidence in the practical application potential of our project.

Our team visited a tea market and had in-depth conversations with several tea distributors to understand the real needs and challenges they face in production and sales. We specifically contacted the manager of Bama Tea, a high-end tea brand. The manager mentioned that customers are generally very concerned about pesticide residues in tea. Although producers strive to keep pesticide residues within safe limits during the production process, the lack of a unified and authoritative reference standard often leaves consumers feeling uneasy.

Through this exchange, we deeply realized the need to make substantial efforts in addressing pesticide residues in tea in order to improve product safety and gain consumer trust. We need to develop effective degradation technologies to help tea producers better manage pesticide residues and ensure that tea quality meets consumer expectations.

We had a discussion with Professor Xiong from Wuhan University, exploring the possibility of using microorganisms to degrade glyphosate. Professor Xiong explained the two main degradation pathways of glyphosate: C-N cleavage and C-P cleavage. Under most natural conditions, microorganisms degrade glyphosate through C-N cleavage into AMPA (aminomethylphosphonic acid) and glyoxylic acid. However, AMPA has significant toxicity, making this degradation method less ideal.

In contrast, the C-P cleavage pathway, which breaks the carbon-phosphorus bond, directly produces non-toxic phosphate (Pi) and glycine. Glycine, as a natural amino acid, can be further metabolized or utilized, making the C-P cleavage pathway superior in terms of safety and efficiency, as it degrades glyphosate without producing harmful by-products.

Compared to traditional methods of screening microorganisms, we can use genetic engineering to modify E.coli to give it the ability to degrade glyphosate. This is because E.coli is easy to culture, has a well-understood genetic background, and can grow and reproduce quickly. Additionally, through genetic modification, we can precisely introduce enzymes related to glyphosate degradation and optimize its metabolic pathway to improve degradation efficiency. This not only enhances the controllability of the research but also provides a more flexible and efficient solution for practical applications.

We introduced the C-P cleavage pathway into E.coli, but in our experiments, we found that the modified E.coli did not degrade glyphosate as effectively as expected and also produced AMPA. To address this, we discussed the issue with Teacher Tang, a Biology Master's at Wuhan University. Teacher Tang pointed out that we had previously mentioned the C-N cleavage pathway of glyphosate in our interviews, and suggested that we consider introducing enzymes related to the C-N cleavage pathway to enhance degradation effectiveness.

In the subsequent experimental design, we decided to introduce the phnO gene, which encodes an enzyme that can effectively convert AMPA into more easily processed derivatives, thereby preventing secondary pollution in the environment.

During the seminar (as presented in the subsequent project implementation section), concerns were raised about the safety of our project. After completing the experiments, we discussed the project with Teacher Yuan. Teacher Yuan emphasized the importance of biosafety in practical applications and explored biosafety control mechanisms with us.

In our discussion, we considered several methods to ensure biosafety. First, it was suggested to culture and process the microorganisms in sealed, double-layered containers to prevent contact with the external environment. However, although this method is effective, it negatively impacts the project's efficiency and is not convenient to operate. Therefore, we also explored other alternatives, such as making microbial growth dependent on external control substances available only in the laboratory, or designing a self-destruction system to ensure that microorganisms cannot survive if they escape into the environment.

After discussing with Teacher Yuan and reviewing relevant literature, we ultimately designed a self-destruction system based on the pCspA cold-inducible promoter and the mazF toxin gene. In this system, the pCspA promoter is activated under low-temperature conditions (similar to outdoor environments), which triggers the expression of the mazF gene. MazF is an mRNA endonuclease that recognizes and cleaves the ACA sequence in mRNA, preventing protein synthesis and ultimately leading to cell death. Through this design, we ensure that E. coli can be automatically eliminated after completing its degradation task, effectively preventing any potential risk of biological leakage.

We had a conversation with Mr. Deng Qing from the Xingche Public Welfare Environmental Organization. Mr. Deng pointed out that glyphosate not only pollutes surface water but also seeps into the groundwater system, causing long-term environmental impacts. He shared his extensive experience in environmental public welfare activities and suggested using clear, concise, and straightforward methods for outreach and education to ensure the content is easy to understand, avoiding unnecessary complexity. He particularly emphasized that students have a greater influence in activities compared to adults, as the public often perceives their motivations as more sincere, leading to greater trust and resonance.

Based on this advice, we created tri-fold brochures for project promotion. This format not only allows the public to better understand our project but also helps us collect feedback to continuously improve and optimize our project. Through intuitive promotional materials, we hope to more effectively convey our message, inspire more people to recognize the impact of glyphosate, and participate in sustainable development initiatives.

At our project's in-person seminar, we not only optimized the project through promotion and feedback collection but also deepened our overall understanding of it. During the discussion, we clearly recognized that by degrading glyphosate, our project helps reduce the entry of harmful substances into drinking water sources, improves aquatic environments, and mitigates threats to aquatic life and human health.

However, some attendees expressed concerns about the general caution society has toward "genetic modification" technology, particularly regarding the potential risks of genetically modified microorganisms uncontrollably spreading in the environment. It was pointed out that if our modified E.coli were accidentally released, it could have unpredictable effects on the environment and other microbial communities.

Given that biosafety has always been a key focus of our project, we discussed effective strategies for ensuring biosafety with Professor Yuan from Wuhan University.

At the second seminar we held, there was an active discussion about the potential impact of the project. Students mentioned that by reducing the entry of chemical pollutants like glyphosate into rivers, lakes, and oceans, our project could effectively protect aquatic habitats and alleviate environmental pressure on aquatic life. In addition, it could help prevent eutrophication and the excessive growth of toxic algae, maintaining ecological balance. However, some attendees expressed concerns about the potential negative impacts of releasing engineered microorganisms into aquatic environments, fearing that it might disrupt existing microbial communities and affect the stability of ecosystems.

In response, we explained that our project is primarily designed for terrestrial environments, such as tea plantations. However, glyphosate not only pollutes surface water but also seeps into groundwater systems, causing long-term environmental impacts. Based on this, we also made recommendations to tea plantations, advising them to reduce glyphosate use at this stage, especially by stopping its application some time before harvest to reduce pesticide residues on crops and the environment. Additionally, we incorporated a self-destruction system in the design to ensure that the engineered microorganisms automatically die after completing their degradation task, preventing any long-term effects on external ecosystems.

During our visit to the wastewater treatment plant, we gained a deeper understanding of how pesticides are treated in wastewater. The staff explained that the microorganisms in the treatment tanks do not need to be replaced because they can use harmful substances as nutrients, continuously purifying the wastewater. This discovery boosted our confidence in developing microorganisms capable of degrading glyphosate.

We had discussions with Teacher Sun from the Chemistry Department of Lanzhou University and Teacher Chen from the Chemistry Department of Wuhan University. Both teachers expressed their support for our project, recognizing our efforts to use microbial technology to degrade glyphosate, which not only protects soil and water resources but also promotes more sustainable agricultural production.

However, both teachers pointed out that if our technology is too complex or costly, like existing chemical technologies, it may limit its broader application, especially for small farmers with limited resources. To address this challenge, we plan to continue developing and optimizing the project in the future to reduce the cost of the technology, making it more economically feasible. This will help facilitate widespread adoption and provide practical, environmentally friendly solutions for agricultural producers, promoting the development of sustainable agriculture.

We also spoke with community managers, who mentioned that glyphosate is the herbicide they commonly rely on for routine weed control in the community. The managers explained that if green areas become overgrown with weeds, it not only affects the community’s appearance but also creates potential hygiene blind spots, leading to mosquito infestations. However, due to concerns about the potential health risks associated with herbicides, they are hesitant to use them frequently. Additionally, they are aware that excessive use of herbicides can disrupt the soil ecosystem and negatively impact the growth of other plants.

When we introduced our project concept to them, they expressed great interest, particularly in the potential of a solution that could eliminate herbicide residues. The managers noted that such a solution would give them more peace of mind when carrying out routine community maintenance, while also reducing the negative environmental impact. This positive feedback further motivated us to deepen our project development to meet the community’s needs for environmental protection and health.

We visited the Hubei Province Premium Agricultural Products Exhibition to promote our work, coinciding with the 2024 International Vine Tea Conference held in Wuhan. This provided us with a valuable opportunity to introduce our project to a broader audience within the tea industry.

During the presentation, our project was well received. We also had a conversation with the owner of a tea shop, who pointed out that our project could indeed help promote the green development of the industry but suggested that we optimize the technology based on specific application scenarios in the future. To further promote our concept, we placed our brochures in the exhibition display.

Looking ahead, we plan to continue optimizing the project to ensure that our technology is more targeted and effective in real-world applications, thus driving the sustainable development of the industry.

Through our conversation with the sanitation worker, we realized that in addition to developing effective technologies to degrade pesticides, it is equally important to raise public awareness of environmental protection and understanding of pesticide use. Therefore, we created tri-fold brochures for outreach and designed posters for display. We went to Luojia Mountain for promotion and also posted the posters in public places such as farmers' markets, hoping to raise public awareness of pesticides and environmental protection.

Through these promotional activities, we hope to capture more people's attention and make them aware of the potential risks of pesticide use and its impact on the ecosystem. We believe that through education and information dissemination, we can encourage the public to take more responsible actions in their daily lives and contribute to the protection of our shared environment.