The Study About The Inhibition Of Oryza Sativa L. Yanjing 9 On The Growth Of Microcystis Aeruginosa And Its Inhibitory Mechanism

This paper was studied the inhibition of Oryza sativa L.Yanjing 9 on the growth of Microcystis aeruginosa and its inhibitory mechanism.The algae-inhibition compounds were extracted,separated and identified.There were three parts:(1)The study about rice culture water(RCW)inhibited the growth of M. aeruginosa:The RCW was collected and mixed into nutrient solution.Then the RCW was used to cultivate M.aeruginosa.The results indicated that:the growth of M. aeruginosa was obviously inhibited.The cell of M.aeruginosa turned to yellow and died.In the experiment,the physiology index of M.aeruginosa changed:the mass growth and chlorophyll content descended observably.The soluble protein content and SOD activity increased firstly,then decreased as the time went on.(2)The inhibitory effect with the aqueous extract of fresh rice straw was the same as the effect with the aqueous extract of sterilized rice straw.The higher rate of quality(rice straw/water),the more obvious the inhibitory effect was.The respiratory rate and SOD activity decreased at first and then increased rapidly.When the straws were smashed into different particle(0.1mm,0.3mm),the particles were used to cultivate M.aeruginosa.The results indicated that:the smaller particles had better algae-inhibition with the same rate of quality.The straw which treated with oxygen degradation time(1d,1w,2w)could inhibit the growth of M.aeruginosa and the straw of 3w or 4w group had no effect.Some physiology index of M.aeruginosa made the relative phenomena.(3)The RCW and rice straw aqueous extract(RSAE)were separated,purified and identified.The two groups were extracted by petroleum ether,ether and ethyl acetate respectively.Then these extracts were concentrated.The extracts were used to do the experiment of the inhibitory effects on M.aeruginosa(by the method of filtering-paper tests on solid medium).The results showed the filtering paper filling with ether extracts shaped the biggest algae- inhibitory ring.The ether extracts further separated into organic acid,phenols substance,neutral substance and alkaline substance and did the experiment of filtering-paper tests on solid medium.It found that organic acid could shape the biggest algae-inhibitory ring and phenols substance was the next one.The organic acid of RCW and RSAE were made an analysis of GC/MS.The analysis showed that there were Tridecanoic acid-12-methyl, Hexadecanoic acid and Octadecanoic acid in RCW;Tridecanoic acid-12-methyl, Hexadecanoic acid,Octadecanoic acid,Benzeneacetic acid and Methoxyacetic acidtridecyl acid in RSAE.In GC/MS analysis,electron fiow image of two groups(the organic acid of RCW and RSAE)were similar and it explained the two organic acids were comparability.A lot of substants could not be identified and it must be separated in the next step.