Purpose: To evaluate the suspending properties of the co-precipitate from
Irvingia gabonesis
gum variety Excelsa (Fam: Irvingiaceae) and gelatin.
Methods: The gum from
Irvingia gabonensis was extracted and co-precipitated with gelatin in gum/gelatin ratios of 1:1, 1:2, 1:3, 1:4, 1:0 and 0:1. The suspending ability of the different ratios was evaluated in magnesium trisilicate suspension, and compared with a suspension prepared with Compound Tragacanth Powder BP (CTP) as well as a commercially available magnesium trisilicate suspension (MTS). The parameters tested were sedimentation rate, flow rate, viscosity, and pH. The effect of mono- and divalent electrolytes on the sedimentation rate of the suspensions was also studied.
Results: In terms of suspending ability, co-precipitated gum-gelatin ratio of 1:2 was comparable to CTP while gum-gelatin ratio 1:3 was a superior suspending agent than CTP with regard to the parameters determined. At 2 % w/v concentration, the suspending ability of the suspending agents were in the rank order: 1:4 > 1:3 > 1:2 > CTP > 1:1 > 1:0 > MTS > 0:1. The 1:3 ratio suspensions also exhibited good stability following addition of mono- and divalent electrolytes although there was significant (p > 0.05) reduction in sedimentation volume.
Conclusion: It can be inferred from the results of this investigation that the suspension prepared with the co-precipitate of
Irvingia gabonensis gum and gelatin as a suspending agent appears to be superior to those prepared with the gum or gelatin alone as well as MTS.
