ANTI-NUTRITIONAL CONSTITUENT OF COLOCASIA ESCULENTA ...

A.2.3.6.3
\.2.3.6.3.1
\.2.3.6.3.2
Lectin
Amadumbe samples were homogenized with a sodium borate buffer m a shaker
overnight. The samples were then filtered and serial dilutions were made.
CoUection ofplatelets
The rats were anaesthetized with ether and blood was immediately collected from
abdominal aorta into centrifuged tube containing ADA (anticoagulant) [1 m! ADA: 5 m!
blood]. The blood was then centrifuged (15 minutes at 1200 rpm, 3 minutes at 2200 rpm
and 15 minutes 3200 rpm) and resuspended in 5 m! ofwashing buffer [1 m! sediment: 20
m! resuspending buffer].
Measurement ofplatelet aggregation
The method ofHwang et al. (1974) as modified by Mekhfi et al. (2004) was adopted for
the measurement ofplatelet aggregation. A 1:20 dilution ofplatelets was prepared in RB.
A sample ofwashed platelets (0.4 ml) was mixed with CaCh to a final concentration of
1.3 mM. Aggregation was initiated by adding 1 Ulm! of thrombin. The development of
platelet aggregation was recorded at 546 um over five minutes.
Experiments with Amadumbe extracts were monitered by pre-incubating the washed
platelets with extracts for one minute. The platelet aggregation was immediately initiated
by adding tbrombin.
Percentage ofstimulation ofclotting was calculated by using the formula:
% stimulation
!:lA control + !:lA test x 100
!:lA control
!:lA is the change in absorbance at 546um
39