Conversion of lactose to methane by defined bacterial cocultures

Abstract

Abstract The conversion of lactose — the main constituent of whey — to methane and carbon dioxide was studied using different defined constructed cultures, imploying strains of Methanosarcina barkeri, Methanobacterium bryantii, Escherichia coli, Acetobacterium woodii, Lactobacillus casei , and Lactobacillus plantarum . The following combinations of strains (food chains) were studied with respect to efficiency and yield of lactose conversion (methane yield in parentheses): E. coli and M. barkeri (4.5–7.6%), E. coli and M. bryantii (13.3%), E. coli, M. barkeri and M. bryantii (54%), L. casei, A. woodii and M. barkeri (93.3%). These conversions were carried out in pH controlled batch fermentations. A very efficient coculture was a combination of L. plantarum with A. woodii and M. barkeri : in chemostat cultures lactose was converted to methane and carbon dioxide with a yield of about 90%, at dilution rates of 0.27 d ‐1 to 0.37 d ‐1 .

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Identifiers

DOI

10.1002/abio.370070412

Journal

Acta Biotechnologica

Year

1987