الفهرس 
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Abstract
The seeds of three legume samples namely kidney beans (Phaseolus vulgaris) Giza 3, Giza 6 and cowpea (VJgIUJ unguiculata) variety Cream 7, were used in this work.
The seeds of three legume samples were germinated in dark. for 120-hr. at l5°C. The effect of gennination on chemical composition, a- amylase inhibitory ICtivities and tannin contents in the seeds germinated for 24,48, 72, 96 and 120 hr. were studied, unsoaked and ungermined seeds served as control.
Changes in some chemical .constituents in the seeds of the three legumes luring germination showed increasing the erode protein from 23.9 to 25.7% in ~~ from 23.1 to 25.1 % and from 21.3 to 24.8% in kidney bean variety Giza 6 lnd Giza 3 respectively by the end of germination period (120 hr.). The same is rue for ash and fiber contents.
After 120 hr. of germination, the total lipids decreased by 38.2, 32.1 and 15.7% of its original levels in ungerminated seeds of cowpea, kidney bean variety Giza 6 and Giza 3 respectively.
The effect of several processing treatments on a- amylase inhibitors and annin contents was also investigated. The results could be summarized as follows :
The a-amylase inhibitors were extracted using O.IM HCI and the erode nhibitors of kidney bean variety Giza 6 was used for studying the effect of several )3l’8Dleters (pre-incubation time of the inhibitory with enzyme, order of addition of :eactants and pH during pre-incubation on the a-amylase inhibitory activity.
The maximal action of the inhibitor on the a- amylases required preencubation of the inhibitor with a-amylase for a minimum of 20 miD. preencubation of the inhibitor with starch for various periods did not alter the nhibitory activity.
The extent of a- amylase inhibition was also dependent on pH during the nteraction of the inhibitors with a- amylases and the pH optimal were 6 - 6.5, 6.5 ·7 and 5.5 - 6 for the inhibition of human salivary a- amylase, porcine pancreatic [·amylase and bacterial a-amylase respectively. The inhibition of the three myIases was marked by decreased below pH 4.5 and above 7.5.
The effect of inhibitor concentration on its activity, under the optimal conditions, showed a linear pattern of inhibition towards porcine pancreatic aamylase, bacterial a-amylase, and human salivary a- amylase up to 35, 50 and 05% respectively with all enzymes a large excess of inhibitor extract nearly romplete inhibition could be observed.
Dialysis of the crude inhibitors against distilled water decreased their letivities against porcine pancreatic a- amylase and bacterial amylase by 35 and \2% respectively. However, their activities against human salivary 0.- amylase were completely lost and the addition of small amounts ofNaCI to the extracts restored the activity. Determination of the 0.- amylase inhibitors in the whole seeds ndicated that cowpea seeds contain higher a- amylase mhibitor than kidney bean leeds especially those active against human salivary (l- amylase and porcine /ancreatic a- amylase (116 and 107 units/ g seed) of the two kidney bean varieties Giza 6 contains higher levels of inhibitory activities against human salivary aalIIlylase (l02 units/g seed), and porcine pancreatic a- amylase (95 units/ g seed) U1an Giza 3 (81 and 78 units/ g seed respectively).
The crude inhibitor of kidney bean variety Giza 3 was the most active 19ainst bacterial a-amylase (86 units/ g seed) followed by cowpea (78 units/ g ieed) and kidney bean variety Giza 6 (56 units/ g seed).
Removal of the seed coat decreased the activities of the inhibitors against the hree different a- amylase by varying degrees. Kinetic studies using the crude
!king or soaking plus cooking was more effective in removing (1- amylase rlbitor from the seeds of three legumes than applying one of these treatments.
The ~ of kidney bean variety Giza 6 contained the highest level oftarmic ,d (5.3 mgl g seed) followed by Giza 3 sample (4.6 mgl g seed) whereas the Npea seed contained the lowest amount (4.1mglg). After decorticating, there was y little tannin dectetable in cotyledons of the three legume studied.
During the :first 24 hr. of germination, tmnin content decreased by 41.5% l43.5 % of its original amounts in ungerminated seeds of cowpea and kidney 11 seed respectively. In subsequent stages of germination the tannin contents tend ~crease as the germination advanced to account for 139, 146 and 246% ofits ~Is in the ungerminated kidney bean variety Giza 3, Giza 6 and cowpea ;eetively by the end of the germination period (120 hr.)
The activity of crude inhibitor of kidney bean variety Giza 61081 19.52 and % of its activity against bacterial a- amylase, human salivary (1- amylase and cine pancreatic (X- amylase respectively after incubation in a boiling water bath 10 min. This was followed by gradual decrease as the time progressed to reach \8, 37 and 32% of its activity against bacterial (1- amylase porcine pancreatic mylase and human salivary (1- amylase respectively.