Research Of Prebiotics-Galactooligosa Ccharides By New Delivery System

Galactooligosaccharides is a kind of functional oligosaccharides what has natural attribute,and is a kind of important prebiotics in breast milk.Galactooligosaccharide s content is high in emulsion.its palatability,water-soluble and stability are well.A nd after it enters the body,it can make the probiotics proliferation,especially bifido bacterium in human intestinal tract.At the same time it also can inhibit the growth of spoilage organisms.So it is to reduce the concentration of serum total cholesterol,improve lipid metabolism in the body and promote mineral absorption,etc.Intestina l probiotics in the use of Galactooligosaccharides to proliferation,at the same time i t also can produce a large amount of extracellular polysaccharide.Extracellular polys accharides not only have antitumor activity and immune activity,but also can promo te probiotic bacteria long-term engraftment in intestine.However,Galactooligosaccharides also are restricted because of its use process c annot be targeted for intestinal cells.In order to overcome this problem,we explore a novel Galactooligosaccharides delivery system.It is using bacterial ghosts?BGs?f rom E.coli as drug delivery vector.Bacterial ghosts are non-denatured envelopes of Gram-negative bacteria with fully intact surface structures for specific attachment to mammalian cells.Experiment successful preparation of qualified ECN bacterial ghosts,ECN cracki ng efficiency is 99.99%.Optimization of process preparation conditions is:the best bacteria when OD₆₀₀ value is around 0.5 start cracking protein,is the best time.LB l iquid medium in pH 7.0 bacteria can better complete the cracking.With ECN proce ss successfully carry Galactooligosaccharides,optimization of carrying conditions it is concluded that:100?L carrying system,Galactooligosaccharides density should be120 mg/mL,shedding dosage should be 2 mg,pick up time should be 12 h,such a system is the optimal carrying system.Use different forms of Galactooligosaccharides to feed mice of intestinal florad were amaged.The influence of the intestinal flora environment in mice of BGs-Gala ctooligosaccharides and naked Galactooligosaccharides were determined by the test.T est results show that BGs-Galactooligosaccharides in regulating intestinal flora of all aspects of the effect is better than naked Galactooligosaccharides and pure bacterial ghosts.Then,we preliminary study the mechanism of the delivery system reduce blood lipid in mice.We use the Real time fluorogenic quantitative PCR?RTFQ PCR?met hods to analyze the amount of HMG-CoA-R and LDL-R expression,use the GAPD H as reference gene.The results indicate that BGs-Galactooligosaccharides delivery s ystem can adjust to HMG-Co A-R and LDL-R gene expression in a certain extent,s o as to regulate the body lipid metabolism.