초록
Production of fructooligosaccharide (FOS) through efficient cultivation of biotransformation process by fructosyltransferase (FTase) was evaluated by two new isolates, Aspergillus niger and Aspergillus flavus NFCCI 2364. The saccharide consumption revealed lag phase of A. niger in 10h which were smaller extent than A. flavus of 14h. For the recycling of cell culture, the pellet cells were continuously reused after 24h of submerged fermentation by these microorganisms in which FTase activity remains stable in four consecutive cycles in A. niger and six cycles in A. flavus. When freshly prepared pellets were sonicated for efficient release of intracellular FTase, the best transformation reaction was performed at 20W acoustic power giving conversion yield of FOS 61.43% (w/w) by A. niger and 70.44% (w/w) by A. flavus respectively. This study was shown that the two fungal isolates can serve as veritable source of intracellular FTase for industrial production of FOS.