Bärlocher Felix
Botanisches Institut der Universität Basel, Schönbeinstrasse 6, CH-4056, Basel, Switzerland.
Oecologia. 1982 Jan;52(1):1-4. doi: 10.1007/BF00349003.
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.
只有在去除可溶性叶片酚类物质后，河蚬（Gammarus fossarum）的肠道提取物才会从刚脱落的橡树叶中释放出还原物质（在pH值≤7时）和氨基酸（pH≥7时）。当羧甲基纤维素的使用浓度与叶片纤维素浓度相当时，还原物质的释放量会显著更高。从分解叶片中提取的真菌酶对结构性碳水化合物有活性，但没有蛋白水解活性。在低pH值下，它们在河蚬肠道酶存在的情况下保持全部活性，在较高pH值下则受到抑制。经过预处理的叶片在接触肠道酶时会释放出更多的还原物质和氨基酸。这种改善程度因用于预处理的真菌种类和预处理时间长度而异。叶片碳水化合物和蛋白质的消化率分别达到峰值，然后下降。河蚬摄入的真菌碳水化合物酶在长达4小时内仍保持一定活性。
