Predicting photosynthetic bacteria-derived protein synthesis from wastewater using machine learning and causal inference.

Journal: Bioresource technology
PMID:

Abstract

Causal inference-assisted machine learning was used to predict photosynthetic bacterial (PSB) protein production capacity and identify key factors. The extreme gradient boosting algorithm effectively predicted protein content, while the gradient boosting decision tree algorithm excelled in predicting protein production, protein productivity, and protein energy yields. Driving factors were identified, with suitable ranges: protein content (pH 6.0-7.5, hydraulic retention time (HRT) < 3.8 d), protein production (biomass > 1.7 g, organic loading rate (OLR) > 9.2 gLd, temperature 26.7-35.0 °C), protein productivity (HRT < 3.5 d, biomass > 1.6 g, OLR > 10.0 gLd), and protein energy yields (light energy 0.1-4.4 kWh, biomass 1.7-65.0 g, chemical oxygen demand (COD) 0.1-2.5 gL). Illuminance, dissolved oxygen, COD, and COD/total nitrogen ratio were causal factors influencing protein production. Two-dimensional partial dependence plot revealed the interaction between two driving factors. This study enhances information on PSB protein production and offers insights for wastewater treatment and sustainable resource development.

Authors

  • Pengfei Hou
    School of Computer Engineering, Jiangsu Ocean University, China.
  • Shiqi Liu
    School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, China.
  • Duofei Hu
    School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, China.
  • Jie Zhang
    College of Physical Education and Health, Linyi University, Linyi, Shandong, China.
  • Jinsong Liang
    School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China.
  • Huize Liu
    School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
  • Jizheng Zhang
    School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
  • Guangming Zhang
    School of Environment and Natural Resource, Renmin University of China, Beijing 100872, China. Electronic address: zgm@ruc.edu.cn.