Studies On The Producing Of Isomaltooligosaccharides From Chestnut Starch And The Proliferative Effects Of Isomaltooligosaccharides On Lactobacillus

In this study, the technology of preparation isomaltooligosaccharide with chestnuts was optimized, and then the separation and purification of isomaltooligosaccharide by ion-exchange chromatography was investigated. Finally, the promotion of proliferative effects of lactobacillus in vitro by homemade chestnut isomaltooligosaccharide (BL-IMO), after separation and purification (BL-IMO-Purified) and commercial isomaltooligosaccharide (IMO-50) was obtained.The results show that, the optimal Chinese chestnut baking conditions of180℃baking15min, the flavor was best under the condition. The optimal condition for the liquefaction techniques were obtained: the mass fractions of chestnuts starch30%, pH6.0, temperature95℃, the addition of thermo-stable α-amylase12U/g every dry starch and100PPM CaCl2for120min, at this time of liquefied liquid DE value of13.8. The adding order of the glucoamylase and glucosyltransferase influenced the contents of isomaltose, panose and isomaltotriose in the production. The glucosyltransferase were added in the liquefaction after saccharification reaction2hours. The addition of fungal-a-amylase10U/g every dry starch, β-amylase5U/g every dry starch, pullulanase0.2U/g every dry starch and glucosyltransferase30U/g every dry starch can produce the contents of isomaltose, panose and isomaltotriose30.53%when the glycoside conversion reaction carried on the20th hour.Isomaltooligosaccharide(30mg/mL) was separated and purified by ion-exchange chromatography on a column (600mm×16mm) packed with732strongly acidic cation exchange resin(Na+). In the ion-exchange separation, the following working parameters were used:volume of sample:10mL; working temperature:71℃; flow-rate of both the sample liquor and the eluant:9mL/min. On this condition, the total elution time was52min, the best reception range was from15mL to40ml, the recovery and mass fraction of isomaltose, panose and isomaltotriose recovery was91.6%and61.5%respectively.The growth-promoting action of isomaltooligosaccharide on lactobacillus was studied in vitro. The results showed that isomaltooligosaccharide was an effective lactobacillus growth-promoting factor, and the best additive amount of BL-IMO, BL-IMO-Purified and IMO-50was2%. The strain of tested lactobacillus grew significantly better in isomaltooligosaccharide-containing medium with2.0%isomaltooligosaccharide as the carbohydrate resource than in glucose-containing medium with2.0%glucose as the carbohydrate resource. Among the three kinds of improved medium, the strain of tested lactobacillus grew significantly better in the medium with BL-IMO-purified as the carbohydrate resource than in the medium with BL-IMO and IMO-50as the carbohydrate resource respectively.