碳源及碳氮比对异养反硝化微生物异养反硝化作用的影响

Effect of carbon source and C/N ratio on heterotrophic denitrification of pure culture.

碳源(甘油和柠檬酸钠)及碳氮比对纯培养的异养反硝化菌HP1 (Pseudomonasalcaligenes)异养反硝化能力影响的试验表明,碳源种类对硝酸还原酶活性没有明显影响,对氧化亚氮还原酶活性有影响。批式培养方式下最适C/N为8,菌株HP1可以利用NO-3 作为唯一氮源进行反硝化作用,证明HP1至少有2种硝酸还原途径。连续培养方式下温度对菌株HP1异养反硝化作用中间产物的积累有影响,不同C/N时均有NH+4 积累,C/N为3时还有NO-2 的积累。

Strain HP1 was isolated from sediment and identified as Pseudomonas alcaligenes.A test was carried out to determine effects of carbon source and C/N ratio on denitrification of pure culture.Results show that carbon source had little effect on nitrate reductase activity,but obvious effect on nitrous oxide reductase activity.The optimal C/N ratio was 8 in batch denitrification tests,and with C/N ratios being<8 or >8,the N_2O concentration was lower under the condition of acetylene inhibition.The study show that Strain HP1 could grow with nitrate as its sole nitrogen source.It was confirmed that nitrate was partly consumed as nitrogen source when denitrification was carried out,and Strain HP1 had two kinds of nitrate reductase at least.There were a lot of intermediates accumulated in continuous culture at different C/N ratio,such as nitrite,ammonium.Temperature had effect on the accumulation of intermediates.Nitrite accumulated at C/N ratio of 3 but no nitrite accumulated at C/N ratio of 20.The objective of the present study was to provide methods for subsequent research.