Aliphatic lipids released from a soil humin after enzymatic degradation of cellulose

A simple and rapid method for the enzymatic hydrolysis of cellulose was applied to the humin originating from an acidic anmoor soil from the Plateau de Millevaches. Degradation of cellulose present in humin frees C9–C20 fatty acids, C12–C20 fatty acid methyl esters, C16–C35 n-alkanes without an odd/even predominance and C16, C18 and C20 n-alkenes. This result shows that cellulose moieties, present in soil humin, are involved in the retention of lipids which cannot be directly extracted with solvents. Lipids freed after cellulose degradation are somewhat different from lipids freed after alkaline hydrolysis, indicating a very heterogeneous structure for this humin.