Eighty four bacterial strains, isolated from various local soils, vegetables
and fruits in decomposition were screened to detect pectinase using citrus
pectin as the sole carbon source according to solid plate assay.
Results showed that 13 strains
showed ability to produce pectinase
depolymerization in assay plate as evidenced by clear hydrolization halos
formed around the colonies. Four strains among them presented considerable
pectinolytic activity since haloes with more than 3 cm in diameter were formed.
Based on morphological and chemical characteristics, 3 strains were classified
as Bacillus subtilis and 1 strain as Bacillus cereus. The Bacillus subtilis (B30)
strain which had the biggest halo and produced high activity of the enzyme was
incubated with polygalactuoronic acid under different conditions of
temperature and pH levels. This strain showed high activity to produce
polygalauoronase at 52°C and pH 9.0. It was concluded that there is an ability
to produce locally alkaline polygalactuoronase which can be used for
manufacturing purposes, especially for treatment the west products of food
processing units to remove pectins.