Biotechnology Bulletin ›› 2021, Vol. 37 ›› Issue (4): 127-136.doi: 10.13560/j.cnki.biotech.bull.1985.2020-1107

Previous Articles     Next Articles

Polyhydroxybutyrate Production from Mixed Waste Cooking Oil by Cupriavidus necator

PAN Lan-jia1,2(), LI Jie2, LIN Qing-huai1, WANG Yin2()   

  1. 1. Amoy Institute of Technovation,Xiamen 361000
    2. Key Laboratory of Urban Pollutant Conversion,Institute of Urban Environment,Chinese Academy of Sciences,Xiamen 361021
  • Received:2020-09-01 Online:2021-04-26 Published:2021-05-13
  • Contact: WANG Yin E-mail:ljpan@iue.ac.cn;yinwang@iue.ac.cn

Abstract:

Waste cooking oil,a kind of hydrocarbon with high carbon content,is one of the main valuable products from the disposal process of kitchen waste. In this study,Cupriavidus necator was employed to synthesize degradable bio-plastics,i.e.,polyhydroxybutyrate(PHB),with mixed waste cooking oil as sole carbon source. The operational conditions of the PHB synthesis from the waste cooking oil were optimized,and the properties of the synthesized PHB were studied. To lay a foundation for the industrialization of PHB in the future,the PHB yields under different modes of fermentation were explored and compared. The results showed that the maximum yields of the C. necator cell dry weight and PHB were 9.5 g/L and 7.6 g/L under the conditions of 30℃,150 r/min,and pH = 7.0 with amount of 3% waste oil and inoculation addition. Furthermore,the yield of PHB reached 8.25 g/L after fermentation for 96 h by batch culture in a 5 L bio-reactor. The average molecular mass of the synthesized PHB in this study was 30 kD,and the polydispersity index(PDI)was 1.44. The melting temperature of PHB was 175.7℃ and a decomposition temperature of it was 285.5 oC,which may meet the requirements of thermoplastic materials.

Key words: waste cooking oil, bio-plastics, polyhydroxybutyrate, Cupriavidus necator