IMPLEMENTATION
Bacterial wilt and related crop diseases severely threaten global food security, while current pesticides are either harmful or ineffective. In 2025, scientists discovered erucamide, a natural plant compound that disarms pathogens by blocking their infection machinery instead of killing them.
Inspired by this breakthrough, we developed ErucaBead—a biodegradable microcapsule containing engineered bacteria that secrete erucamide. With a PVA outer shell for stability and controlled release, each bead delivers a precise, eco-friendly, and farmer-friendly dose: just dissolve in water and apply.
ErucaBead provides a safe, scalable, and sustainable solution for bacterial wilt control and offers a promising platform for future green agriculture.
PRODUCT DESIGN
ErucaBead: An Engineered Microcapsule System for Plant Protection
BACKGROUND: THE CHALLENGE OF CONTROLLING BACTERIAL WILT
As global agriculture scales up in intensity, plant pathogens pose growing threats to crop productivity. One
of the most persistent challenges is bacterial wilt, caused by Ralstonia solanacearum. This soil-borne
pathogen invades the plant’s roots, blocks the xylem, and ultimately causes systemic wilting and death in
economically important crops such as tomato, potato, and chili.
Traditional control measures—chemical pesticides, antibiotics, and copper-based agents—often come with problems: environmental toxicity, unclear dosage, increasing resistance, and limited adoption by smallholder farmers. Biological control methods, while eco-friendly, tend to suffer from inconsistent results or technical complexity.
To address these challenges, our team designed ErucaBead—a standardized, eco-friendly, and easy-to-use microbial bead that leverages synthetic biology and materials science to provide a precise, field-deployable solution to bacterial wilt, especially for farmers in tropical and subtropical areas like southern China.
Traditional control measures—chemical pesticides, antibiotics, and copper-based agents—often come with problems: environmental toxicity, unclear dosage, increasing resistance, and limited adoption by smallholder farmers. Biological control methods, while eco-friendly, tend to suffer from inconsistent results or technical complexity.
To address these challenges, our team designed ErucaBead—a standardized, eco-friendly, and easy-to-use microbial bead that leverages synthetic biology and materials science to provide a precise, field-deployable solution to bacterial wilt, especially for farmers in tropical and subtropical areas like southern China.
DESIGN PHILOSOPHY: PRECISE. SAFE. SIMPLE.
We believe that an ideal microbial agricultural product should meet three essential criteria. Farmers often
lack microbiology knowledge and cannot easily determine the correct concentration or frequency of
application, so our bead system ensures a fixed number of living cells per capsule for consistent delivery.
At the same time, the encapsulated bacteria must remain viable during storage and transport while activating
only under field conditions; our PVA-based microcapsules maintain a protective microenvironment until
application. Inspired by laundry pods, we designed the beads for direct use: simply drop one bead into
water, stir, and apply, with no complicated procedures or equipment required.
COMPONENTS AND FUNCTIONAL MODULES
(1) OUTER SHELL: WATER-SOLUBLE HIGH-ALCOHOLYSIS PVA FILM
We selected high-degree alcoholysis polyvinyl alcohol (PVA) film as our encapsulation material because of
its unique combination of properties. It dissolves rapidly in water, with a 100 cm², 75 µm thick film fully
dissolving in under one minute with gentle stirring, allowing for quick field application. PVA is
biodegradable, broken down by soil microbes into CO₂ and water, with studies showing over 75% degradation
within 46 days, leaving no plastic residue. Once dissolved, it also improves soil structure by enhancing
aggregation, moisture retention, and air permeability, which indirectly benefits root development. The film
offers strong mechanical strength, with a tensile strength of approximately 63.7 MPa and elongation over
400%, preventing rupture during storage and transport. Its anti-static and dust-repellent properties reduce
external contamination and extend shelf life. Furthermore, PVA is inexpensive, widely available, and
compatible with industrial-scale processing methods such as casting or injection molding, making it ideal
for scalable productization.
(2) CORE PAYLOAD: ERUCAMIDE-SECRETING ENGINEERED BACTERIA
Inside the capsule lies a genetically engineered strain of E. coli, designed to continuously synthesize and
secrete erucamide—a long-chain fatty amide derived from rapeseed oil, widely used in food packaging and
lubricants, and recently explored for its agricultural potential.
Unlike harsh chemical antimicrobials, erucamide provides a gentle and targeted protection mechanism. It
forms a hydrophobic layer around the plant root surface, reducing pathogen adhesion and colonization, while
potentially interfering with bacterial motility and membrane properties to weaken infection. Preliminary
research also suggests that erucamide may trigger Induced Systemic Resistance (ISR) in host plants,
enhancing their natural immunity.
Our engineered strain is designed with robust biosafety features, including kill switches and containment systems, to prevent uncontrolled release into the environment. For more information, please refer to our Safety page.
Our engineered strain is designed with robust biosafety features, including kill switches and containment systems, to prevent uncontrolled release into the environment. For more information, please refer to our Safety page.
To ensure product consistency, effectiveness, and scalability, we developed a streamlined and
reproducible microencapsulation workflow:
1.Preparation of the PVA solution
A 10–12% (w/v) solution of high-alcoholysis PVA is prepared by dissolving the polymer in deionized water under constant stirring and heating (80–90°C) until fully transparent.
2.Culture of engineered bacteria
The erucamide-secreting E. coli is grown in large-scale bioreactors under optimal conditions, harvested at high density, and centrifuged to concentrate cells. The bacterial suspension is then buffered and standardized for dosage control.
1.Preparation of the PVA solution
A 10–12% (w/v) solution of high-alcoholysis PVA is prepared by dissolving the polymer in deionized water under constant stirring and heating (80–90°C) until fully transparent.
2.Culture of engineered bacteria
The erucamide-secreting E. coli is grown in large-scale bioreactors under optimal conditions, harvested at high density, and centrifuged to concentrate cells. The bacterial suspension is then buffered and standardized for dosage control.
3.Formation of core suspension
The concentrated bacterial suspension is mixed with a protective matrix (e.g., glycerol, trehalose, or sodium alginate) to stabilize cell activity and enhance encapsulation performance.
The concentrated bacterial suspension is mixed with a protective matrix (e.g., glycerol, trehalose, or sodium alginate) to stabilize cell activity and enhance encapsulation performance.
4.Microcapsule fabrication
Using a droplet-forming device (e.g., vibrating nozzle or microfluidic jet), the core suspension is dispensed into the PVA solution. The system allows the simultaneous formation of spherical droplets which are air-dried or crosslinked to form stable bead-like microcapsules.
5.Drying and packaging
The beads are gently dried under controlled temperature and humidity to preserve bacterial viability. Final products are stored in moisture-resistant packaging under refrigeration or room temperature, depending on shelf-life requirements.
This manufacturing pipeline is compatible with industrial-scale equipment and can be readily adapted for GMP-compliant production.
Using a droplet-forming device (e.g., vibrating nozzle or microfluidic jet), the core suspension is dispensed into the PVA solution. The system allows the simultaneous formation of spherical droplets which are air-dried or crosslinked to form stable bead-like microcapsules.
5.Drying and packaging
The beads are gently dried under controlled temperature and humidity to preserve bacterial viability. Final products are stored in moisture-resistant packaging under refrigeration or room temperature, depending on shelf-life requirements.
This manufacturing pipeline is compatible with industrial-scale equipment and can be readily adapted for GMP-compliant production.
FIELD APPLICATION: FROM LAB TO LAND
ErucaBead is designed for seamless use by farmers without any scientific training. The standard application
steps are:
1.Dissolution: Drop one capsule into a defined volume of water (e.g., 1 liter) and stir until fully dissolved.
2.Delivery: Apply the solution to the root zone via spraying or irrigation.
3.Action begins: Once the PVA dissolves, engineered bacteria are released, colonize the rhizosphere, and start secreting erucamide to create a natural protective layer.
This process is compatible with common agricultural practices such as drip irrigation, root drenching, and foliar spraying, ensuring broad usability.
1.Dissolution: Drop one capsule into a defined volume of water (e.g., 1 liter) and stir until fully dissolved.
2.Delivery: Apply the solution to the root zone via spraying or irrigation.
3.Action begins: Once the PVA dissolves, engineered bacteria are released, colonize the rhizosphere, and start secreting erucamide to create a natural protective layer.
This process is compatible with common agricultural practices such as drip irrigation, root drenching, and foliar spraying, ensuring broad usability.
PROSPECTS AND IMPACT
We envision ErucaBead as a next-generation microbial bioproduct designed to enhance plant resistance while
reducing reliance on chemical treatments. It offers a targeted mode of action specific to Ralstonia
solanacearum, leaving beneficial microbes largely unaffected. The product is eco-friendly, producing no
harmful byproducts or chemical residues, and is fully biodegradable. Additionally, it is farmer-friendly,
with simple and intuitive use requiring no special training, and cost-effective, as scalable production
enables affordable pricing suitable for smallholders and developing regions.
ErucaBead has particular relevance in southern China, Southeast Asia, and other tropical agricultural zones, where bacterial wilt poses a serious threat. With its combination of safety, efficacy, and ease of use, it has the potential to become a new standard in managing this challenging plant disease.
ErucaBead has particular relevance in southern China, Southeast Asia, and other tropical agricultural zones, where bacterial wilt poses a serious threat. With its combination of safety, efficacy, and ease of use, it has the potential to become a new standard in managing this challenging plant disease.
FUTURE DEVELOPMENT
Looking ahead, we plan to further optimize the formulation and stability of the bacterial suspension inside
ErucaBead to ensure long-term viability and effective performance in the field. Unlike traditional
protein-based delivery systems, ErucaBead encapsulates live engineered bacteria, presenting both unique
challenges and opportunities. We are testing various cryoprotectants, osmoprotectants, and buffer systems to
improve the long-term survival of the engineered E. coli during storage and transport. At the same time, the
internal environment of the bead is being fine-tuned to keep the bacteria dormant until release into the
soil, preventing premature activation. Ongoing shelf-life experiments monitor cell activity and erucamide
secretion under different temperature and humidity conditions, while preliminary field trials evaluate
bacterial behavior across diverse soil types, pH levels, and irrigation systems common in tropical and
subtropical agriculture.
In parallel, we are exploring potential platform extensions for other beneficial bacteria or traits, such as nitrogen fixation or fungal resistance, using the same encapsulation method. This approach could create a versatile, modular system for synthetic biology–based plant protection and enhancement, expanding the applications of ErucaBead beyond bacterial wilt management.
In parallel, we are exploring potential platform extensions for other beneficial bacteria or traits, such as nitrogen fixation or fungal resistance, using the same encapsulation method. This approach could create a versatile, modular system for synthetic biology–based plant protection and enhancement, expanding the applications of ErucaBead beyond bacterial wilt management.
PROMOTION
LEGAL ANALYSIS
LEGAL ANALYSIS
As a new type of engineered microbial biopesticide, ErucaBead represents an innovative attempt to use
synthetic biology and material science in agriculture. However, this also means that existing agricultural
regulations—largely designed for chemical pesticides and fertilizers—may not fully apply to such emerging
products.
To anticipate potential challenges, we plan to conduct an in-depth study of Chinese and international laws concerning genetically modified organisms (GMOs), microbial fertilizers, and biocontrol agents. We summarized the applicable classification standards, biosafety requirements, and market access procedures. This legal groundwork will help ensure that ErucaBead can move smoothly from laboratory research into commercialization, while strictly complying with safety and environmental protection laws.
By building this foundation early, we aim to avoid regulatory uncertainty and provide references for other teams working on similar microbial products.
Proposal of Microbial Biopesticide Standards
Through our legal and regulatory analysis, we discovered that current laws often lag behind technological innovation. For emerging products such as engineered microbial capsules, there is no specific industrial standard yet.
In light of this, and guided by a strong sense of responsibility, we drafted a Proposal for Chinese Microbial Biopesticide Industry Standards. The proposal outlines safety indicators for genetically engineered strains and encapsulation materials, standardized testing protocols for biodegradability, soil compatibility, and storage stability, as well as guidelines for field application, including recommended dosages and safe operation methods.
We hope to seek opinions from agricultural experts and local promotion centers in the future.
, whose advice will help us refine the draft and enhance its practical feasibility. This effort not only supports the future promotion of ErucaBead but also contributes to the long-term safety, reliability, and sustainability of China’s biopesticide industry.
To anticipate potential challenges, we plan to conduct an in-depth study of Chinese and international laws concerning genetically modified organisms (GMOs), microbial fertilizers, and biocontrol agents. We summarized the applicable classification standards, biosafety requirements, and market access procedures. This legal groundwork will help ensure that ErucaBead can move smoothly from laboratory research into commercialization, while strictly complying with safety and environmental protection laws.
By building this foundation early, we aim to avoid regulatory uncertainty and provide references for other teams working on similar microbial products.
Proposal of Microbial Biopesticide Standards
Through our legal and regulatory analysis, we discovered that current laws often lag behind technological innovation. For emerging products such as engineered microbial capsules, there is no specific industrial standard yet.
In light of this, and guided by a strong sense of responsibility, we drafted a Proposal for Chinese Microbial Biopesticide Industry Standards. The proposal outlines safety indicators for genetically engineered strains and encapsulation materials, standardized testing protocols for biodegradability, soil compatibility, and storage stability, as well as guidelines for field application, including recommended dosages and safe operation methods.
We hope to seek opinions from agricultural experts and local promotion centers in the future.
, whose advice will help us refine the draft and enhance its practical feasibility. This effort not only supports the future promotion of ErucaBead but also contributes to the long-term safety, reliability, and sustainability of China’s biopesticide industry.
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