桔皮水提液对铜绿微囊藻生长的抑制效果研究

桔皮水提液能显著抑制铜绿微囊藻的生长，定性滤纸过滤，0.45 μm滤膜过滤和0.22 μm滤膜过滤及高温灭菌水提液的预处理操作对其抑藻效果无明显影响. 当桔皮（干质量）水提液投加质量浓度大于1.0 g/L时，培养10 d时对铜绿微囊藻生长的抑制率可超过90%，抑制率随桔皮水提液投加质量浓度的升高而增大；当桔皮水提液的投加质量浓度低于0.1 g/L时，抑藻效果不明显. 在长期（40 d）培养试验中，投加低质量浓度（小于1.0 g/L）桔皮水提液的试验组中，铜绿微囊藻在培养后期生长迅速，某些试验组中出现促进铜绿微囊藻生长的现象；投加高质量浓度（大于1.0 g/L）桔皮水提液的试验组中，培养40 d内均保持接近于100%的抑制率. 透析袋分离试验表明，具有抑藻活性的物质存在于分子量小于3 500的组分中. 由试验结果可推测，桔皮水提液中含有某种或某些物质，可对铜绿微囊藻的生长产生抑制作用，且这些物质经121 ℃高温处理30 min后仍保持抑藻活性. 该抑藻物质易于自然降解，在长期培养过程中，其抑藻效果会逐渐消失. 

nhibitory Effect of Extract from Citrus Peel on Growth of Microcystis aeruginosa

The inhibitory effects of four kinds of pretreated （filtered by ordinary qualitative paper filter, 0.45 μm filter, 0.22 μm filter, and autoclaved）Citrus peel （dry peel equivalent） extract on Microcystis aeruginosa growth were tested. The results showed that all the four pretreated extracts have obvious inhibitory effect on the growth of M. aeruginosa, with an inhibitory ratio over 90% in the present of concentrations higher than 1.0 g/L after 10 days of cultivation, and the inhibitory ratios increased with the concentrations of the extract. There was little inhibitory effect when the extract concentration was lower than 0.1 g/L. In the long time （40 days） cultivation experiments, the inhibitory ratios ofthe low concentration group （less than 1.0 g/L） decreased during the later period, and some even showed stimulative effects. But the inhibitory ratios stayed around 100% through the 40 days with the concentrations of the extract larger than 1.0 g/L. The results of the dialyzer separation showed that the effective materialshould have a molecular weight less than 3 500. It was deduced that there was some material in the Citrus peel inhibiting the growth of M. aeruginosa, and the material can keep its inhibitory effect after being autoclaved （121 ℃, 30 min）. And also the material can be easily degraded in natural conditions, resulting inthe inhibitory effects disappearing gradually in the long time period cultivation.