The Optimization of Fructosyltransferase Production
by Aspergillus sp WNIC

Aris Toharisman, Triantarti dan Hendro Santoso M
Indonesian Sugar Research Institute
E-mail: isri@telkom.net

ABSTRACT

Fructo Oligo Saccharides (FOS) which are considered biological benefits, have been developed recently to be used as functional factors in health-food. FOS show low cariogenicity, nondigestibility, proliferation of bifidobacteria in human intestinal tract and dietary fiberlike action. FOS posses these unique health beneficial effects and can be found wide applications in food and pharmaceutical industries. FOS are natural bifidobacteria enhancers. These natural food ingredients can maintain microbial balance in intestinal tract and be called functional factors or nutraceauticals. Prospect of FOS can be applied on variety of foods as a sweetener in hard candy, dessert, topping and spread, soft cream, bread, drinks, dairy products, sweeten milk, feeds and pharmaceutical industry. Addition of FOS in food not only provides biological functionality but also improves the final products appearance and physical properties. The aim of this research was to produce FOS from sucrose by using fructocyltransferase (FT-ase) from Aspergillus sp. Research on the production of fructo-oligosaccharrides (FOS) was optimization of FTase production. Inoculum of selected Aspergillus was added into medium with various composition and incubation conditions. Enzyme solution was mixed with sucrose and incubated at various times, pHs, temperatures, and agitations. The best parameter condition was based on the highest FT-ase activity. The results showed that production of FT-ase was affected by Fermentation time, pH’s and incubation temperature. The carbon source tested permitted good growth and enzyme production where sucrose supported rather good enzyme production. It was obvious that enzyme production was not closely correlated with cell growth. The best Fructooligosaccharide yield (20,53%) was achieved when 20 g/100 ml sucrose was utilized. Yeast extract was good nitrogen source for enzym production. The best FT-ase activity was achieved when 1,2 g/100 ml yeast extract was utilized. Addition of mineral salt also enhanced enzyme production where 1 g/l Magnesium salt gave the best cell growth and enzyme production.
Keywords: sucrose, fructooligosaccharide, fructosyltransferase, alternative sweetener