Mixotrophic cultivation of Chlorella for local protein production using agro-food by-products

Bioresour Technol. 2017 Apr:230:82-89. doi: 10.1016/j.biortech.2017.01.030. Epub 2017 Jan 16.

Abstract

A local strain of Chlorella vulgaris was cultivated by using cheese whey (CW), white wine lees (WL) and glycerol (Gly), coming from local agro-industrial activities, as C sources (2.2gCL-1) to support algae production under mixotrophic conditions in Lombardy. In continuous mode, Chlorella increased biomass production compared with autotrophic conditions by 1.5-2 times, with the best results obtained for the CW substrate, i.e. 0.52gL-1d-1 of algal biomass vs. 0.24gL-1d-1 of algal biomass for autotrophic conditions, and protein content for both conditions adopted close to 500gkg-1 DM. Mixotrophic conditions gave a much higher energy recovery efficiency (EF) than autotrophic conditions, i.e. organic carbon energy efficiency (EFoc) of 32% and total energy efficiency (Eft) of 8%, respectively, suggesting the potential for the culture of algae as a sustainable practice to recover efficiently waste-C and a means of local protein production.

Keywords: By-products carbon; Chlorella vulgaris; Energy efficiency; Mixotrophic; Protein production.

MeSH terms

  • Agriculture*
  • Amino Acids / analysis
  • Autotrophic Processes
  • Batch Cell Culture Techniques
  • Biomass
  • Biotechnology / methods*
  • Chlorella vulgaris / growth & development*
  • Chlorella vulgaris / metabolism
  • Food*
  • Glycerol / analysis
  • Nitrogen / analysis
  • Phosphorus / analysis
  • Proteins / metabolism*

Substances

  • Amino Acids
  • Proteins
  • Phosphorus
  • Nitrogen
  • Glycerol