Bida Iryna, Moliszewska Ewa, Matik Kacper, Ślusarczyk Aleksandra, Pawliczek Dominik, Havryliuk Olesia, Hovorukha Vira, Tashyrev Oleksandr
Department of Extremophilic Microorganisms Biology, D.K. Zabolotny Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine, Kyiv, 03143, Ukraine.
Institute of Environmental Engineering and Biotechnology, University of Opole, 45-040, Opole, Poland.
Sci Rep. 2025 Mar 26;15(1):10437. doi: 10.1038/s41598-025-88601-4.
Heavy metals, particularly cobalt and nickel, are highly toxic and widely distributed in ecosystems. Sometimes, their concentration in natural ecosystems can increase sharply due to anthropogenic activities. Metal-resistant microorganisms are considered to be promising for their detoxification. The purpose of the work was to study the sustainability of microorganisms derived from the biohumus in the presence of toxic cobalt and nickel compounds as well as determine the maximum limit concentration of Co and Ni for them. The biohumus served as a model natural ecosystem free from heavy metals where microorganisms were not adapted to them. The resistance of microorganisms was determined by cultivation in the medium with a gradient of simultaneous Co and Ni from 0 to 1000 mg/L. The quantification of Co and Ni-resistant microorganisms in the biohumus was determined by counting the number of colony forming units on nutrient agar. Using a Niton XL5 Plus manual XRF analyzer, it was determined that in metal missile fragments the concentration of cobalt ranged from 73 ± 22 to 589 ± 34 mg/kg, the concentration of nickel was 110 ± 15-577 ± 21 mg/kg. Cobalt was not detected in all soil samples. Nickel compounds were detected in two samples of the affected soil up to 408 ± 8 mg/kg and 36 ± 4 mg/kg in soil without shell explosions. On the example of the microorganisms of the biohumus, we confirmed that natural ecosystems contain microorganisms resistant to toxic Co and Ni compounds in high concentrations. The concentrations of simultaneous Co and Ni of 100 and 200 mg/L were established not to affect the growth of microorganisms, and the number of CFUs was (6.2 ± 0.2)×10 and (6.1 ± 0.2)×10 CFU/g. The maximum permissible concentration of simultaneous Co and Ni for the biohumus microbiome was 700 mg/L and the number of CFUs was (5.0 ± 0.1)×10 CFU/g after a month of cultivation. Moreover, microorganisms can adapt and maintain sustainable growth even after the increase in the concentration of metals from 500 to 2500 mg/L as well as to provide the detoxification of divalent metals by transforming into insoluble non-toxic sulfides.
重金属，尤其是钴和镍，具有高毒性且在生态系统中广泛分布。有时，由于人为活动，它们在自然生态系统中的浓度会急剧增加。抗金属微生物因其解毒作用而被认为具有潜力。这项工作的目的是研究在有毒钴和镍化合物存在的情况下，源自生物腐殖质的微生物的耐受性，并确定它们对钴和镍的最大极限浓度。生物腐殖质作为一个不含重金属的天然生态系统模型，其中的微生物尚未适应这些重金属。通过在同时含有从0到1000毫克/升梯度的钴和镍的培养基中培养来确定微生物的抗性。通过计算营养琼脂上的菌落形成单位数量来确定生物腐殖质中抗钴和镍微生物的数量。使用尼通XL5 Plus手持式X射线荧光分析仪测定，在金属导弹碎片中，钴的浓度范围为73±22至589±34毫克/千克，镍的浓度为110±15至577±21毫克/千克。并非所有土壤样本中都检测到钴。在受影响土壤的两个样本中检测到镍化合物，在没有炮弹爆炸的土壤中镍化合物含量分别高达408±8毫克/千克和36±4毫克/千克。以生物腐殖质中的微生物为例，我们证实天然生态系统中含有对高浓度有毒钴和镍化合物具有抗性的微生物。已确定同时含有100和200毫克/升钴和镍不会影响微生物的生长，菌落形成单位数量分别为(6.2±0.2)×10和(6.1±0.2)×10 CFU/克。经过一个月的培养，生物腐殖质微生物群落对同时存在的钴和镍的最大允许浓度为700毫克/升，菌落形成单位数量为(5.0±0.1)×10 CFU/克。此外，即使金属浓度从500毫克/升增加到2500毫克/升，微生物也能适应并保持可持续生长，并且通过转化为不溶性无毒硫化物来实现二价金属的解毒。
