Mutation Breeding Of Productive Strain Of High Molecular Weight γ-Poly(Glutamic Acid) And Study On Preparation Of γ-Poly Glutamic Acid Hydrogel

γ-Poly(glutamic acid) (γ-PGA) is one of the polymers with good biocompatibility. It is an extra cellular polymer produced by certain Bacillus species.γ-PGA is an unusual anionic naturally occurring homo-polyamide made up of D- and L- glutamic acid units connected by amide linkages between a- amino andγ- carboxylic acid groups. It is water soluble, biodegradable, edible and non-toxic toward humans and the environment. Therefore , potential applications ofγ-PGA and its derivatives have been of interest in the past few years in a broad range of industrial fields such as food, cosmetics, medicine, plastics, oil recovery and water treatment and it is expected to be used for sustained release materials, drug carrier, drug controlled release, highly water absorbable hydrogels and biodegradable fibers. Production ofγ-PGA was most extensively studied and work has been carried out on the nutritional requirements for cell growth, improving conditions forγ-PGA production. So it is a novel bioproductions that is worth to exploitation and using.Becauseγ-PGA has an extensive potential value to exploitation and apply in the society, this article adopted a novel idea of more effective mutation breeding to treat Bacillus licheniformis ATCC 9945A, which can produceγ-PGA effectively, which is totally different from the traditional way. And in the novel idea, we can obtain mutant strain with good characters effectively.Our lab have did some research on increasing the production ofγ-PGA. We have improved its output from 4. 582g/L to about 20g/L But as the output has been improved, the degree of aggregation.hasn't been improved, either. So I better the conditions of mutation breeding. Consider the intrinsic viscosity as impact factor as well as the output at the same time.Otherwise, we also have studied the best conditions of esterifyingγ-PGA and how to prepareγ-PGA hydrogel. Meanwhile, we also have measured the absorption rate ofγ-PGA hydrogel. As the result improved that using solidγ-PGA 0.5g, NMP as solvent, oil bath with 60℃, under magnetic force whisk, add NaHCO3 , 1-Bromobutane 125μl and 35μl Allylbromide, esterifies 19h can get esterifiedγ-PGA. With this kind ofγ-PGA 0.1g, add 20μL HEMA and 6mg AIBN, oil bath with 80℃, ventilate N2 to isolate 02, under magnetic force whisk during 2h can getγ-PGA hydrogel (Z-2). After measure, the result shows thatγ-PGA hydrogel(Z-2) can absorb water 44 times as its self weight.