The Study Of A Fungus Which Can Produce β-fructofuranosidase Of Enzymatic Activity And The Application Of β-fructofuranosidase

β-fructofuranosidase is abroad in the biology world. The character of the enzyme from different microbes were different. Many microbes such as AspergiIlus niger, Arthrobacter sp. and Aspergillus oryzae can produceβ-fructofuranosidase. The molecule ofβfructofuranosidase is constituted of 1～8 subunits, which comparative quality is 11 000～409000D. The active mechanism ofβ-fructofuranosidase is that it breaks the bond of B (1? 4) of the cane sugar, which generates fructose and glucose. Then many fructoses polymerize the fructooligosaccharide with the enzyme.Soybean oligosaccharides include functional factors (raffinose and stachyose)and nonfunctional factor(sucrose). Commercial products from soybean oligosaccharides in China markets have low content of functional oligosaccharides, about 30～40%. It was investigated in this study that soybean oligosaccharides were extracted from the soybean whey, and modified by enzymes to increase its functional oligosaccharides.An Aspergillus niger which can produceβ-fructofuranosidase, of high enzymatic activity was examined from one Arthrobacter sp and one AspergiIIus niger. The optimum culture conditions were 66-72h at 28℃, and the culture medium was 10Bx corn syrup, 3%sucrose, 0.35%peptone, 0.034%bitter salt, it's original pH is 6. The enzyme solution was concentrated 2.5 times by alcohol. The characters of B-fructofuranosidase are (1) theβ-fructofuranosidase was stable below 40℃; (2) theβ-fructofuranosidase Was stable between pH 5 and pH 7; (3) theβ-fructofuranosidase was activated by Mg²⁺,Zn²⁺and inactivated by Ag⁺; (4) the optimum enzymic synthesis of fruto-oligosacchatides using soybean oligosaccharides as donor and acceptor was pH value 6-7, 31.5℃(reaction temperature), 1.8g (enzyme concentration)and 1.5 h (reaction time). The oligosaccharides content were increased from 30.98% to 48.6%.