Team:NCKU Tainan/Description

Description

Background

Food crisis and water pollution will become one of the greatest challenges by 2050. Thankfully, fishery gives us relative sustainable resource to meet the ever-growing demand. With capture fishery remaining static, aquaculture has been responsible for the rapid growth and it reaches half of world total production of aquatic animals.

Successful aquaculture needs good water quality, especially the nitrate concentration should be under control. If the nitrate concentration is too high, the fish will easily get sick and even die. To lower the nitrate level , the easiest and cheapest way for fish farmers is replacing the dirty water by groundwater. Obviously, there exists two problems.

First, groundwater sustains the buildings’ foundation. Over pumping groundwater leads to the ‘’Stratum Subsidence’’ and also results in ‘’Seawater Intrusion’’ and follows by ‘’Soil Salinization’’----This phenomenon is quite familiar in Tainan, where contributes to 1/4 of total value of aquaculture production in Taiwan

Second, the farmers rarely treat the huge amount of waste water for economic purpose. They directly pour untreated water into the river, which leads to algae overgrowing, blocking the sunshine and destroying water ecosystem.

These problems do not only exist in southern Taiwan but also happen worldwide. For example, groundwater levels in Punjab have dropped 10 meters since 1979. To stop this, our team try to eradicate it from the root---‘’Reducing nitrate concentration in water’’. We want to solve the problems within micro-organism while not disturbing the industry. Thus, we created a sensing and intermediate regulating system named "NO problem" to treat exceed nitrate. In this way, we keep water in good quality and reduce water usage to prohibit problems from worsening.

Sensing Device & Sensing Bacteria

Sensing device of "NO problem" is a boat equipped with servomotor and control module. It is designed to contain a pH meter, a thermometer and a nitrate sensor. See more detail

Nitrate sensor is a device with reactor and laser. The reactor contains genetically modified E. coli and will emit different fluorescence intensity when dealing with various concentration of nitrate in water. By determining the fluorescence level and cross-referring with data lines which we've constructed in advance, we can accurately calculate the concentration of nitrate in water. Additionally, pH meter and thermometer allow us to obtain basic information of water. After determining those characteristics of water, combining with GPS data we will upload them to a server and transfer those data to our App. By using smartphone, the users can easily get the information about their fish pond immediately. They can make the appropriate solution before it is too late to regulate the water quality. For the sake of mobility and portability, we construct this device into a boat, which can move around to collect data and is convenient to carry.

The biological method in our nitrate sensing system shows below: We use a promoter which named PyeaR. This promoter has strong specificity in sensing the concentration of nitrate in the water. And in case to collect the data more easily, the GFP gene has also been constructed on our plasmid. Furthermore, we use the lyophilized E. coli powder instead of E. coli broth to imitate the condition of our device and also give a more stable detecting system. We use the nitrate which concentration less than 100 ppm to test the function of PyeaR. See more detail

Regulation Device & Bacteria

After testing the abnormal data, our boat will notify the fishfarmers through app, and they can turn on the regulation system, which can change nitrate to glutamine in four critical steps.

First, nitrate is transformed into nitrite by NaR cluster, which exists in E. coli originally. Second, nitrite reductase (NiR) changes nitrite into ammonium. Third, glutamate dehydrogenase (GDH) turns ammonium into glutamate. Last step, glutamine synthetase (GS) catalyzes glutamate into glutamine. We put all these genes into E. coli.

We did a lot of experiments to construct and test the function of our bricks. All of the laboratory tests get good results, which means our team successfully convert nitrate waste into useful substance. See more detail

This constructed E. coli is coated on scouring pad and work within our regulation box. Also, we have tested the our regulation box and the results are satisfying.

Integrated HP

Our integrated HP included four interviews with aquaculture experts and one street survey. Experts divided into academic institution and local industry. The former we chose ‘’Center of Shrimp Disease Control and Genetic Improvement’’ and the latter included one Prawn fishing owner and an aquaculture farmer. See more detail Moreover, we went to an aquaculture farm to know the environment in reality. See more detail
Furthermore, we did collaboration with MDHS, CSMU and NTHU. We also joined 2017 Asia Pacific Conference.
For education, we endeavored in three parts: elementary school education, high school education and college promotion. We held 5 weeks popular science classes in elementary school, visited two high schools: NEHS and KGHS to share the concept of synthetic biology and our project. In college promotion, we set up stand in our school annual festival and held two presentation. See more detail

Conclusion

To solve nitrate problem, our sensing boat collects samples and identify its location by GPS system. The sensing data will be sent to the server through Wi-Fi and be analyzed immediately and push to the cloud through the internet. If the level of nitrate is higher than expected, our regulation box can turn on automatically, pump out the water and remove 99% of the nitrate in it.
In this way, we regulate the nitrate concentration to make fish alive instead of using large amounts of water, which avoids over pumping groundwater and follow-up ecological crisis. We used micro-organism to change all the problems into "NO problem "