| Abstract
| - β-Mannanase from Penicillium oxalicum SO efficiently hydrolyzed guar galactomannan to galacto-manno-oligosaccharides. Gel filtration estimated the molecular weight of the β-mannanase as 35 000and SDS−PAGE as 29 000. The optimum pH was around 5 while a stable pH was reached in therange of 3−6. Optimum temperature was around 60 °C at pH 5, while under 60 °C activity wasstable. HPLC analysis detected oligosaccharides with degrees of polymerization (DP) of 2 to 7 and2 to 6 released on hydrolysis of guar and locust bean gums, respectively; about 92% of the releasedsugars were oligosaccharides. In analysis of the sugar distribution on MALDI-TOF-MS, major productsof DP 6 and 7 and DP 5 and 6 were confirmed in hydrolysates of guar gum and locust bean gum,respectively. One of the main oligosaccharides released from guar gum, with DP 7, had a highgalactose content (Gal/Man = 0.76) and corresponded to a blockwise galactose-substituted mannantype in galactomannan. Keywords: β-Mannanase; guar gum; galactomannan; locust bean gum; oligosaccharides; Penicilliumoxalicum
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