Through cell surface display technology, we got the EcN which can degrade sulfadiazine. Our next step is to mass-produce our engineered strain through a probiotic production plant in an industrialized manner, and finally sell them in the form of lyophilized powder.
We will use an industrialized method to inoculate and ferment bacteria on a large scale. The strains are inoculated into an intermediate fermenter containing sterile medium under aseptic conditions, freeze-dried to remove bound water and adsorbed water, and concentrated to obtain engineered strain.
Our end users will be farmers. Since the famers have a low level of education, we specially designed a biogas digester specifically for the degradation of sulfadiazine. Its use method is quite simple, just pour the freeze-dried powder and livestock manure into it and press a button, it will work automatically. But the design of the septic tank is not simple: after the manure is collected from each household, the mixer will mix the manure, and the biogas emitted in the middle can be passed to each household as a fuel. At the same time, the strong ultraviolet rays in the sewage pipe will completely kill the genetically modified EcN that may leak. After sterilization and stirring, the manure will be deposited into layers, the upper liquid will be treated, and the digestate can be directly used as a safe fertilizer for agriculture. Up till now, our septic tank design has processed livestock manure that is at risk of genetic leakage into harmless fuel and fertilizer, bringing benefits to farmers.
As lyophilized powder is produced in large batches and shipped to farmers in various locations, wholesale large quantities of lyophilized powder at one time may cause it to deteriorate and expire. So, we will find ways to produce lyophilized powder with long shelf life (2-3 years) in the future.
In order to be used, out products need to bring benefits to farmers. As our projects cannot directly make farmers profitable, we will combine our septic tank model design to give farmers a favor. For most farms have septic tanks, so we will retrofit existing septic tanks, which will save them money. In addition, the local government, which was originally responsible for dealing with antibiotic residues, will also reduce taxes and provide benefits for farmers who use our products.
Last but not least, we also pay attention to biosecurity. To solved the issue that our engineered strains may flow out of the digester and mutate into superbugs, UV rays are set up in the sewage pipe of the digester. Once the sulfadiazine is degraded, the engineered strains will be killed.
The original project planned to feed the whole-cell catalyst directly to livestock. However, we concluded from our interviews that farmers were concerned about the degradation of antibiotics in the guts of livestock would reduce the effectiveness of antibiotics against large-scale plagues. Therefore, the plan was abandoned.