Abstract:
:Gut extracts of Gammarus fossarum liberated reducing substances (at pH values ≤7) and amino acids (pH≥7) from freshly shed oak leaves only after removal of soluble leaf phenols. When carboxymethylcellulose was used at a concentration equal to that of leaf cellulose, release of reducing substances was considerably higher. Fungal enzymes extracted from decomposing leaves were active against structural carbohydrates but showed no proteolytic activity. At low pH values, they retained their full activity in the presence of gut enzymes of G. fossarum, at higher pH values they were inhibited. Conditioned leaves released larger amounts of reducing substances and amino acids when exposed to gut enzymes. The improvement varies with the fungal species used for conditioning and with the length of the conditioning period. The digestibility of leaf carbohydrates and proteins reached separate peaks and then declined. Fungal carbohydrases ingested by G. fossarum retained some activity for up to 4h.
journal_name
Oecologiajournal_title
Oecologiaauthors
Bärlocher Fdoi
10.1007/BF00349003subject
Has Abstractpub_date
1982-01-01 00:00:00pages
1-4issue
1eissn
0029-8549issn
1432-1939pii
10.1007/BF00349003journal_volume
52pub_type
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