Rubio L A, Grant G, Bardocz S, Dewey P, Pusztai A
Rowett Research Institute, Bucksburn, Aberdeen.
Br J Nutr. 1991 Nov;66(3):533-42. doi: 10.1079/bjn19910053.
The effects of raw faba bean (Vicia faba L., minor) meal (VFM) and its fractions on the growth and nitrogen utilization of rats have been determined in two experiments. Two commercial varieties of VFM were tested, local VFM (409-439 g/kg diet) and Troy VFM (439 g/kg diet). The bean fractions tested were V. faba lectin-depleted protein (VFDP), V. faba lectin (VFL) and V. faba cotyledon residue (VFCR). All diets were supplemented with amino acids to target requirements. Body-weight, body N and lipid contents of rats fed on VFM were reduced significantly in comparison with control rats fed on lactalbumin. This was due, in part, to the lower digestibility of the protein, lipid and dry matter (DM) of VFM diets. As a result, net protein utilization (NPU) and biological value (BV) of faba bean proteins were less than expected. Urine and urea-N outputs of the VFM-fed rats were also elevated in both experiments. Increasing the energy content of local VFM diets led to significantly higher dry body-weight, body N and lipid contents, with the result that the NPU and BV values of the protein also increased. However, the NPU values for VFM-fed rats were still significantly lower than those for the controls in both experiments. In contrast, true N, lipid and DM digestibilities in rats given local VFM were not significantly affected by the difference in the energy content of the diets. The replacement of two-thirds of the lactalbumin in the diet with VFDP (65 g/kg) reduced dry body-weight, N and lipid contents, NPU and BV compared with the control rats, even though N, lipid and DM digestibilities were not significantly different. The nutritional performance of rats fed on lactalbumin-based diets containing 7 g VFL/kg was similar to that of the controls. Similarly, the inclusion of the cotyledon residue (237 g VFCR/kg diet) had no appreciable effect on any of the variables studied. As VFL and VFCR had no antinutritional effects in these rats, it appears that the low nutritional value of VFM for rats (NPU 0.66) results not only from the low digestibility of the bean proteins, but also from disturbances in N metabolism.
在两项实验中测定了生蚕豆（蚕豆属小粒种）粕（VFM）及其组分对大鼠生长和氮利用的影响。测试了两种市售品种的VFM，本地VFM（日粮中含量为409 - 439 g/kg）和特洛伊VFM（日粮中含量为439 g/kg）。测试的蚕豆组分有蚕豆凝集素缺失蛋白（VFDP）、蚕豆凝集素（VFL）和蚕豆子叶残渣（VFCR）。所有日粮都补充了氨基酸以达到目标需求量。与喂食乳白蛋白的对照大鼠相比，喂食VFM的大鼠体重、体氮和脂质含量显著降低。这部分是由于VFM日粮中蛋白质、脂质和干物质（DM）的消化率较低。因此，蚕豆蛋白的净蛋白质利用率（NPU）和生物价（BV）低于预期。在两项实验中，喂食VFM的大鼠的尿液和尿素氮排出量也有所升高。提高本地VFM日粮的能量含量导致干体重、体氮和脂质含量显著增加，结果蛋白质的NPU和BV值也增加。然而，在两项实验中，喂食VFM的大鼠的NPU值仍显著低于对照组。相比之下，喂食本地VFM的大鼠中，日粮能量含量的差异对真氮、脂质和DM消化率没有显著影响。用VFDP（65 g/kg）替代日粮中三分之二的乳白蛋白，与对照大鼠相比，降低了干体重、氮和脂质含量、NPU和BV，尽管氮、脂质和DM消化率没有显著差异。喂食含7 g VFL/kg的乳白蛋白日粮的大鼠的营养性能与对照组相似。同样，添加子叶残渣（日粮中237 g VFCR/kg）对所研究的任何变量都没有明显影响。由于VFL和VFCR对这些大鼠没有抗营养作用，看来VFM对大鼠的营养价值低（NPU为0.66）不仅是由于蚕豆蛋白消化率低，还由于氮代谢紊乱。
