Locust bean gum:
Locust Bean Gum (LBG) (also known as Carob Gum) is
obtained form the refined endosperm of seeds from the carob
tree Ceretonia Siliqua L. It is an evergreen tree of the legume
family. Carob bean gum is obtained by removing and
processing the endosperm from seeds of the carob tree.
Processing of the ground endosperm is accomplished by
dispersing the fine powder in boiling water and filtering to
remove impurities. The gum is recovered by evaporating the
solution and tray or roll drying .
Locust bean gum (LBG) is a plant seed galactomannan,
composed of a 1-4 linked !-D-mannan backbone with 1- 6-
linked "-D-galactose side groups . This neutral polymer is
only slightly soluble in cold water; it requires heat to achieve
full hydration, solubilization and maximum viscosity .
The physico-chemical properties of galactomannan are
strongly influenced by the galactose content .
A controlled delivery system for propranolol hydrochloride
(PPHCL) using the synergistic activity of LBG and xanthan
gum (X) was studied. Granules of PPHCL were prepared by
using different drug: gum ratios of X, LBG alone and a
mixture of XLBG (X and LBG in 1: 1 ratios). The XLBG
matrices exhibited precise controlled release than the X and
LBG matrices because of burst effect and fast release in case
of X and LBG alone respectively and there was no chemical
interaction between drug and polymers in the XLBG
formulation as conformed by FTIR studies. The first-pass
effect of PPHCL can be avoided by using this formulation .