School of Civil and Environmental Engineering, and National International Cooperation Base On Environment and Energy, University of Science and Technology Beijing, 30 Xueyuan Road, 100083, Beijing, People's Republic of China.
Bull Environ Contam Toxicol. 2014 Mar;92(3):358-63. doi: 10.1007/s00128-013-1163-8. Epub 2013 Nov 24.
Microcalorimetric technique was applied to assess the toxic effect of EDTA-chelated trivalent iron on Pseudomonas putida (P. putida) (bacterium), Candida humicola (C. humicola) (fungus) and their mixture in sterilized soil. Microbial growth rate constant k, total heat evolution Q T, metabolic enthalpy ∆H met, mass specific heat rate J Q/S, microbial biomass C and inhibitory ratio I were calculated. Results showed that microcalorimetric indexes decreased with the increasing Fe(III)-EDTA complex concentration. Comparing the single and mixed strains, the effect of Fe(III) on bacterium-fungus interaction was dominant at lower dose, whereas, the metal toxicity at high dose of Fe was the main factor affecting P. putida and C. humicola activity. Thus, the mixture had moderate tolerance to the iron overload, and exhibit synergistic interaction in exponential growth phase (0-0.3 mg g(-1)). The results of glucose degradation showed that glucose was consumed totally at the end of exponential phase of microbial growth.
应用微量热技术评估了 EDTA 螯合三价铁对灭菌土壤中铜绿假单胞菌（P. putida）（细菌）、卷枝毛霉（C. humicola）（真菌）及其混合物的毒性效应。计算了微生物生长速率常数 k、总热量 Q T、代谢焓 ∆H met、比热速率 J Q/S、微生物生物量 C 和抑制比 I。结果表明，随着 Fe(III)-EDTA 络合物浓度的增加，微量热指标降低。比较单菌株和混合菌株，在较低剂量下，Fe(III)对细菌-真菌相互作用的影响占主导地位，而在高剂量下，金属毒性是影响 P. putida 和 C. humicola 活性的主要因素。因此，混合物对铁过载具有中等耐受性，并在指数生长阶段（0-0.3mg g(-1)）表现出协同相互作用。葡萄糖降解的结果表明，在微生物生长的指数期结束时，葡萄糖被完全消耗。
