Improving production of lactic acid and volatile fatty acids from dairy cattle manure and corn straw silage: Effects of mixing ratios and temperature

Bioresour Technol. 2022 Sep:359:127449. doi: 10.1016/j.biortech.2022.127449. Epub 2022 Jun 10.

Abstract

Anaerobic co-fermentation (AcoF) of dairy cattle manure (DCM) and corn straw silage (CSS) for producing lactic acid (LA) and volatile fatty acids (VFAs) was investigated. Batch experiments were conducted at seven different DCM/CSS ratios and at mesophilic and thermophilic temperatures. Results indicated that the highest concentration of LA was 17.50 ± 0.70 g/L at DCM:CSS ratio of 1:3 and thermophilic temperature, while VFAs was 18.23 ± 2.45 g/L at mono-CSS fermentation and mesophilic temperature. High solubilization of thermophilic conditions contributed to LA accumulation in AcoF process. Presence of the CSS increased the relative abundance of Lactobacillus for LA production at thermophilic. Meanwhile, the abundance of Bifidobacterium was increased when CSS was added at mesophilic, which could conduce to VFAs production. This study provides a new route for enhancing the biotransformation of DCM and CSS into short-chain fatty acids, potentially bringing economic benefits to agricultural waste treatment.

Keywords: Agricultural waste; Anaerobic co-fermentation; Bacterial communities; Hydrolysis performance; Short-chain carboxylic acids.

MeSH terms

  • Anaerobiosis
  • Animals
  • Bioreactors / microbiology
  • Cattle
  • Fatty Acids, Volatile
  • Fermentation
  • Lactic Acid
  • Manure* / microbiology
  • Silage*
  • Temperature
  • Zea mays

Substances

  • Fatty Acids, Volatile
  • Manure
  • Lactic Acid