Life Cycle Assessment of Pilot-Scale Bio-Refining of Invasive Japanese Knotweed Alien Plant towards Bio-Based Bioactive Compounds

Japanese knotweed is an invasive alien plant species with characteristic rapid expansion in Europe and North America and resistance to extermination. It displaces autochthonous biodiversity and causes major damage to infrastructure, thus causing global ecological and economic damage. The Japanese knotweed plant is usually eradicated using various chemical, biological, or mechanical techniques, which at a large scale include heavy equipment, usually followed by incineration. Therefore, excavation is preferred to eradication techniques, and as a biomass waste recovery method due to the extraction of high-value biocompounds. This is supported by the fact that the Japanese knotweed possesses various bioactive compounds with beneficial effects on human health. Its rhizome bark extract produces strong and stable antioxidant activity over time, as well as apoptotic, antibacterial, and other beneficial activities. In this work, an environmental impact assessment, including greenhouse gas footprint, acidification, eutrophication, and ecotoxicity for extraction route of the Japanese knotweed rhizome bark, is performed. A comparative case study between the lab-based and proposed pilot-scale production of active added-value extract was evaluated. The results show the pilot-scale production exhibits lower environmental burdens, mainly due to greater electricity requirements for the lab-scale alternative.

Automated summary

Japanese knotweed is an invasive alien plant species that rapidly expands in Europe and North America and is resistant to extermination. It causes significant ecological and economic damage by displacing native biodiversity and damaging infrastructure. Various techniques, such as chemical, biological, or mechanical methods, are used to eradicate the plant, with excavation being the preferred technique due to the extraction of high-value biocompounds. An environmental impact assessment of the extraction route for Japanese knotweed rhizome bark is conducted, showing that pilot-scale production has lower environmental burdens than lab-scale alternative mainly due to electricity requirements.