Sudathip Titapoka Chantorn, Katesarin Buengsrisawat, Apinya Pokaseam, Tasanee Sombat, Pichamon Dangpram, Kla Jantawon, and Sunee Nitisinprasert

pp. 17 - 22

Abstract

Effects of media composition, and physical properties on the production of crude mannanase by Penicillium oxalicum
KUB-SN2-1 were investigated. P.oxalicum KUB-SN2-1 was propagated in a shaking incubator at 30°C with rotation speed of
200 rpm of 7 days. The specific activity obtained during growth on robusta coffee residues (RCR) of 16.21 U/mg protein was
much higher than other carbon sources tested. For nitrogen sources, yeast extract (0.11 U/mg protein) and ammonium nitrate
(0.09 U/mg protein) showed maximum specific activity. Hence, guar gum was the best inducer for producing mannanase (14
U/mg protein). For evaluating the optimal concentration, the result showed that 1% guar gum, 0.5% yeast extract, 0.25%
ammonium nitrate, and 0.25% RCR were the suitable sources of inducer, organic nitrogen, inorganic nitrogen, and carbon,
respectively. Modified medium with initial culture pH of 5.0 at 30°C was optimum for mannanase production (53.77 U/ml for
3 day). Reducing sugars were analyzed by dinitrosalicylic acid methods. The highest reducing sugar of 7517.82 g/ml
was obtained from copra meal hydrolysate after 30 h.