Study On The Interaction Between Heavy Metal Ions Cd²⁺,Pb²⁺ And Rhodosproridium Toruloides

In recent years,the rapid development of the industrial economy has led to the growing problem of heavy metal pollution.Heavy metals not only cause pollution to the natural environment,but also threaten the movement of animals and plants and human health.Heavy metal contamination of terrestrial environment has been significant issue for people more recently.At the same time,fossil fuels such as oil and natural gas are in short supply,and new energy development is also urgent.Microbial oil is an emerging green energy source and a bioenergy source that is highly promising for replacing fossil energy.This paper aims to investigate the growth of Rhodosproridium Toruloides at different temperatures and the concentration of heavy metals,the ability to adsorb heavy metals and the content of oil.It provides certain reference value for heavy metal pollution control and new energy development.The Rhodosproridium Toruloides was cultured at 25°C and 30°C,and a certain concentration of heavy metal Cd²⁺and Pb²⁺were added to the medium to investigate its growth under heavy metal stress,heavy metal adsorption and oil content.Rhodosproridium Toruloides under different concentrations of Cd²⁺and Pb²⁺stress were sampled at 24,48,72,96 and 120 hours at 25°C and30°C.The OD₆₀₀00 value was detected by spectrophotometer to reflect the growth condition.The adsorption amount of heavy metal was detected by high performance liquid chromatography,and the improved acid heat method was used to extract the oil of yeast to characterize the oil content.The experimental results show that at a culture temperature of 25°C and 30°C,a certain concentration of heavy metal Cd²⁺can inhibit the growth of Rhodosproridium Toruloides,and the greater the concentration,the more obvious the inhibition,when the Cd²⁺concentration is?200.0mg/L,The inhibition of Rhodosproridium Toruloides was most pronounced.The sorption of heavy metal Cd²⁺by Rhodosproridium Toruloides is very impactful.At 25°C culture temperature,the equilibrium adsorption efficiency reached 97.20%when the Cd²⁺concentration was 50 mg/L.At30°C,the same concentration equilibrium adsorption efficiency was 88.80%.A certain concentration of Cd²⁺promoted the accumulation of oil in Rhodosproridium Toruloides.At the end of 120 hours of culture,the oil content reached 75.18%and 63.16%at 25°C and 30°C,respectively,and the oil content was higher than the control group.At 25°C and 30°C culture temperature,a certain concentration of heavy metal Pb²⁺has no obvious inhibitory effect on Rhodosproridium Toruloides.Rhodosproridium Toruloides has a certain adsorption effect on heavy metal Pb²⁺.At 25°C,the equilibrium adsorption efficiency is59.65%when the Pb²⁺concentration is 15 mg/L;at 30°C,when the Pb²⁺concentration is 45.0mg/L,the equilibrium is balanced.The adsorption efficiency is up to 53.67%.At 25°C,Rhodosproridium Toruloides had a good adsorption effect on low concentration Pb²⁺.At 30°C,Rhodosproridium Toruloides had a good adsorption effect on high concentration Pb²⁺.A certain concentration of Pb²⁺promoted the accumulation of oil in Rhodosproridium Toruloides.The oil content of the experimental group was slightly higher than that of the control group.By kinetic fitting of the adsorption data,the results showed that the adsorption of Cd²⁺and Pb²⁺by Rhodosproridium Toruloides was in accordance with the Lagergren quasi-second-order kinetic equation,and the process of adsorbing Cd²⁺by Rhodosproridium Toruloides was also in accordance with the standard.The kinetic equation,at the same time,the process of adsorption of Cd²⁺and Pb²⁺by Rhodosproridium Toruloides is in accordance with the law of Langmuir adsorption model.