Preliminary Study On Hyaluronic Acid Produced By Bordetella Sp. B4

Hyaluronic acid(HA) is a kind of polysaccharide widely found in human and animals' body.There are over 70 years since Mayer has discovered HA in cow's eyes in 1930s.HA,which is the major extracellular matrix component,has unique viscoelastic and physiological functions,such as maintaining water,lubrication, adjustment of the osmotic pressure,protecting normal cells from the toxic cells, avoiding the invasion of free radicals and influencing the cell proliferation and differentiation.Therefore,HA is widely used in orthopedics,ophthalmology, gynecology,surgical adhesions defense,plastic surgery and health food and other fields.Bordetella sp.B4 is a gram-negative bacterium which was screened from soil by our lab.It is used to oxidize cholesterol and produce cholesterone.We found a kind of anion polysaccharide accompanied with the production of cholesterol oxidase. Therefore,the bacterium was cultured in the fermentation medium and after the optimization of production medium,the production of polysaccharide increased a lot, and can reach stable production of 8 g/L,which is much more than the traditional hyaluronic acid-producing strains,Streptococcus zooepidemicus and Pasteurella multocida.DEAE anion exchange column and molecular sieve Sephadex G100 were applied to the purification of the polysaccharide,and the structure of the purified polysaccharide was analyzed by infrared,HPLC and NMR,and the results indicated that the structure of this acidic polysaccharide are similar to that of hyaluronic acid. This is the first time to discover that the polysaccharides production and the use of cholesterol is related,and Bordetella sp.B4 is a new polysaccharide-producing strain which reached 8 g/L more other known polysaccharide-producing strains.In a fermentation culture,Bordetella sp.B4 could produce three kinds of valuable products (cholesterol oxidase,androgen and polysaccharide),and the bacteria is not harmful to people and animals so that it could be widely used in large-scale industrial production.