Fructosyl transferase activity in the tissue‐macerating preparation, pectolyase Y‐23*: physiological role of fructosyl transfer in Aspergillus and significance for studies of fructan synthesis in grasses

摘要: summary Pectolyase Y-23 is a commercially available plant tissue-macerating preparation derived from culture filtrates of Aspergillus japonicus. When incubated with 600 mol m−3 sucrose at pH 5.5 and 30 °C, pectolyase catalyzed the rapid synthesis oligofructans. During 5 h incubation, 53 % original mass substrate was converted to oligofructan. Thin layer chromatography (TLC) indicated that predominant products were trisaccharide isokestose tetrasaccharide nystose, though fructans up degree polymerization (DP) 6 also detected. The oligofructan accompanied by release large amounts free glucose, but fructose minor product reaction, indicating low activity invertase in preparation. fructan stable during incubation periods 24 showing absence hydrolase fructosyl transferase reaction similar reactions enzymes other spp. In particular, strongly resembled industrial commercial sugar product, Neosugar. The concentration kinetics glucose determined parameters Vmax Km for transfer calculated as 218 nkat mg−1 67 respectively. partially purified quaternary-amine ion exchange chromatography. Pectolyase has previously been used barley leaf protoplasts. exhibited properties those reported enzyme.