MSAD: Methanosarcina detection and addition for optimised anaerobic digestion
- Project lead
- Caroline Hayley Orr
- Institute
- Teesside University
Summary:
MSAD will demonstrate the potential of Methanosarcina as an inoculant for the AD industry and develop an optimised method for detection.
Anaerobic digestion (AD) is a complex biological process whereby organic waste is broken down to produce biogas. Previously we have worked with a range of AD facilities at different scales and observed the digester microbial community differed relating to waste feed and system productivity. Methanogensis, the production of methane, is often the rate limiting step. Methanosarcina abundance was correlated with optimised digestion. Therefore, we propose using Methanosarcina as an inoculant for the AD industry to improve biogas production. Monitoring the microbial communities within AD takes time, money, and expertise. Developing a simple testing system which allows monitoring of key members of the community allows for quick measurement of digester health and targeted optimisation.
We will investigate the robustness of Methanosarcina inoculants within a trial system to test their ability to colonise. We will then investigate several methods for quickly identifying Methanosarcina by optimising a qPCR system allowing faster and cost-effective alternatives to sequencing approaches.
This project meets the BBSRC industrial biotechnology scope by creating a method for targeted optimisation of AD. AD converts waste biomass to biogas, reducing waste for industry as well as creating a higher value product allowing generation of renewable energy. This reduces dependency on petrochemicals and reduces reliance on fossil fuels. Diverting waste to AD and optimising the process reduces emissions of green-house gases from landfill and from the running of AD facilities.
Aims:
Anaerobic digestion (AD) allows microbial breakdown of waste and conversion to biogas for renewable energy generation. Many different waste products are used meaning AD systems have to be robust to change. If we understand how AD microbial communities respond to change we can optimised biogas yield. We aim to:
· trial the use of Methanosarcina, a promising methane producing microbe, as an inoculant for AD improvement
· Determine an assay for simple measurement of Methanosarcina as an indicator of AD health
Outcomes:
The microbial communities which breakdown waste to produce biogas are complex. We have identified that the presence of Methanosarcina, a methane producing archaea has correlated with higher biogas yield within AD systems. We took various concentrations of inoculants which contained Methanosarcina and mixed them with inoculants which contained alternative methane producing microbes. We were able to use sequencing tools to show that Methanosarcina was able to colonise all of the samples regardless of the microbes within the original inoculant. We then exposed the inoculants to sludge waste from the wastewater industry and demonstrated that Methanosarcina was able to remain colonised within the system and effectively contribute to methane production from the breakdown of the waste. We measured genes which are involved in methane production and observed that they were increased when Methanosarcina was present suggesting increased methane production. This shows the potential for use of Methanosarcina as an inoculant within AD.
Impact:
AD provides renewable energy meaning optimisation can reduce fossil fuel use. Developing robust AD inoculants increases the potential of more waste streams to AD improving the circular economy. Tracking microbial communities provides a tool for tracking the health of an AD system ensuring changes to process parameters before AD failure.
Monitoring microbial communities within AD is challenging as it involves using DNA sequencing approaches which are costly and require expertise. We were also able to use new primers and an optimised qPCR method to identify Methanosarcina within AD digestate.
Academic partners: Dr Caroline Orr, Teesside University
Industrial partners: Matt Hooper, Northumbrian Water
