摘　要：砷（As）具有高毒性、致癌性和致畸性，砷污染土壤对环境和人类健康构成了巨大的威胁。将As（Ⅲ）氧化为As（Ⅴ）是治理砷污染的关键步骤。本文从砷污染的水稻土中分离纯化出两株有砷氧化能力的菌株A1-13、A1-24，对这两株菌进行表征和砷氧化特性分析，并通过水稻盆栽试验研究其对水稻砷污染的修复作用。试验结果表明：A1-13属于无色杆菌属，在温度25℃、pH 7.0的条件下培养24 h后，砷氧化率约为95%；A1-13有良好的抗As（Ⅲ）能力，在As（Ⅲ）质量浓度最高为1 000 mg/L的条件下依然能够生长繁殖，当As（Ⅲ）质量浓度大于600 mg/L时，砷氧化率显著降低；A1-24属于鞘氨醇杆菌属，在温度30℃、pH 6.4的条件下培养，砷氧化率约为60%；As（Ⅲ）质量浓度大于400 mg/L时，其生长受到抑制，As（Ⅲ）质量浓度大于200 mg/L时，砷氧化率显著降低。在水稻盆栽试验中，与未加菌株的空白对照组相比，施加A1-13和A1-24菌株发酵液后水稻米砷的含量分别降低了37.83%、29.42%。本研究分离出的两株高效功能菌株为水稻砷污染治理提供了新的微生物资源，并对利用高效功能微生物修复砷污染土壤具有一定的参考价值。
关键词：砷污染；砷氧化菌；水稻；砷氧化率；稻米砷含量
中图分类号：X53；S511　　　　　　文献标志码：A　　　DOI：10.3969/j.issn.1007-7146.2025.02.011

Abstract: Arsenic (As) has the characteristics of highly toxic, carcinogenic and teratogenic, arsenic contaminated soil poses a great threat to the environment and human health. The oxidation of As(Ⅲ) to As(V) is a key step of arsenic pollution control. In this study, two strains A1-13 and A1-24 with arsenic oxidation ability were isolated and purified from arsenic contaminated paddy soil. The characterization and arsenic oxidation characteristics of these two strains were analyzed, and their ability to reduce arsenic pollution in rice was tested in a pot experiment. The main research results were as follows: A1-13 was identified as a strain of Achromobacte sp.. After 24 hours of cultivation at 25℃ and pH 7.0，the arsenic oxidation rate of strain A1-13 was about 95%. A1-13 had good resistance to As(Ⅲ) and could grow and reproduce under the highest As(Ⅲ) mass concentration of 1 000 mg/L. When the concentration of As(Ⅲ) exceeds 600 mg/L, the arsenic oxidation rate significantly decreases. A1-24 was identified as a strain of Sphingobium sp. The arsenic oxidation rate of strain A1-24 was about 60% at 30℃ and pH 6.4. When the mass concentration of As(Ⅲ) was greater than 400 mg/L, the growth of strain A1-24 was inhibited. When the concentration of As(Ⅲ) was greater than 200 mg/L, the arsenic oxidation rate of strain A1-24 decreased significantly. In the pot experiment, compared with the blank control without bacterial strains, the arsenic content in rice with A1-13 and A1-24 added decreased by 37.83% and 29.42%, respectively. The discovery of two functional strains in this study provided a theoretical reference for controlling arsenic pollution in rice and had certain reference value for using highly efficient functional microorganisms to treat arsenic contaminated soil.
Key words: arsenic pollution; arsenic-oxidizing bacteria; rice; arsenic oxidation rate; arsenic content in rice
（Acta Laser Biology Sinica, 2025, 34(2): 184-192）