The Separation And Structure Analysis Of Algicidal Active Substances In A Strain Of Bacillus

Against t he proble ms of serious eutrophication and disasters thatChina’s lakes are facing， it is necessary to expl ore the effective way tocontrol the digit of plankton， inhibit algal blooms and i mprove the waterquality of lakes． As a n i mportant part of st ructure and function o faquatic ecosyste m biological populations， algicidal bacteria plays animportant role in the maintenance of algal biomass ba lance． So meforeign re searchers hold an opinion that the sudden dyi ng out of algalblooms probably relates to algicidal bacterial infection. Thus it hascaused more and more attention as the microbe t o prevent algal blooms．1. qualitative research of active materials in algicidal bacteriaAfter a preliminar y study on algicidal mecha nis m， the algicidaleffect of bacterial extracellular fluid was found． The chemical separationmethod was used for the separation of Lysing Bacillus T1—separatingalgicidal active ma terials from extracellular metabolites． It was shownthat the algicidal efficiency was highest in the environment of LB culturemedium a nd pH=9. By high t e mperature and treatme nt of Pro.K and pH，algicidal activity had a weak effect． The lysing probability was upon97%, indicating that the active substances were not protein.2. the separation and identification of active ma terials in Lysing BacillusT1Choosing Bacillus a myloliquefaciens T1as the experi me nt materialfour substances were separated from its extracellular metabolites by silica gel column chromatography and HPLC. Separating and purifying toget the relatively pure algicidal compositions with silica gel columnchromatography a fter a se ries of pre-treatment. In the process ofseparation, TLC was used t o track e very step of products and al gicidalactivity. In the experime nt, detailed analysis was done to the activesubstances A2that Bacillus T1pr oduc ed including Infrare d Spectroscopy(IS), HPLC, LC-MS and so on. Firstly, according to IS it was shown thatthe absor ption of3379c m-1s tood for a cid hydroxyl or a mi ne of Chung, o f1339c m-1stood for C-N stretching of aromatic, of1409c m-1stood forbenzene r ing(it is the characteristic absorption of the be nzene ring), of1114c m-1stood for C-O bond, of749c m-1and702c m-1st ood for be ndingvibration in the benzene ring of aromat ic hydrogen surface. It was prove dthat the replaced type of benzene ring was mono-substituted benzene.Secondly, according to IS a nd HPLC the functi onal groups contained inthe substances of t he first, third and forth pea ks were s peculated to belysine, phenylalanine and tryptophan through the compari son of dat abase.Through t he study on algicidal activity, it was known t hat lysine andphenylalanine had some cert ain synergistic effect, but t ryptophan ha dlittle effect.