Recently, the use of microalgae for bioremediation of pharmaceuticals(Ph As) has attracted increasing interest. However, most studies focused more on microalgae removal performance, its defensive response to the Ph As...Recently, the use of microalgae for bioremediation of pharmaceuticals(Ph As) has attracted increasing interest. However, most studies focused more on microalgae removal performance, its defensive response to the Ph As during wastewater treatment remains unexplored. Herein, microalgal three defensive systems have been investigated in synthetic wastewater, with six Ph As as the typical drug. Results show that Ph As could bind to EPS, and this action in turn could help to alleviate the direct toxicity of Ph As to microalgae. Subsequently, the physiological analyses revealed the increase of superoxide dismutase(SOD), catalase(CAT), and peroxidase(POD) activities, potentially reducing the oxidative stress induced by Ph As. Furthermore, the enzyme activities of cytochrome P450(CYP450) and glutathione-S-transferase(GST) were significantly upregulated after exposure to SMX, CIP and BPA, followed by a significant decrease in biodegradation rates after the addition of CYP450 inhibitors, suggesting that the biotransformation and detoxification of Ph As occurred. Meanwhile, molecular docking further revealed that CYP450 could bind with Ph As via hydrogen bond and hydrophobic interaction, which proved their abilities to be metabolized and form transformation products in microalgae. These findings provide an advancing understanding of microalgae technologies to improve the treatment of wastewater contaminated with Ph As.展开更多
Microalgal-indigenous bacterial wastewater treatment(MBWT)emerges as a promising approach for the concurrent removal of nitrogen(N)and phosphorus(P).Despite its potential,the prevalent use of MBWT in batch systems lim...Microalgal-indigenous bacterial wastewater treatment(MBWT)emerges as a promising approach for the concurrent removal of nitrogen(N)and phosphorus(P).Despite its potential,the prevalent use of MBWT in batch systems limits its broader application.Furthermore,the success of MBWT critically depends on the stable self-adaptation and synergistic interactions between microalgae and indigenous bacteria,yet the underlying biological mechanisms are not fully understood.Here we explore the viability and microbial dynamics of a continuous flow microalgae-indigenous bacteria advanced wastewater treatment system(CFMBAWTS)in processing actual secondary effluent,with a focus on varying hydraulic retention times(HRTs).The research highlights a stable,mutually beneficial relationship between indigenous bacteria and microalgae.Microalgae and indigenous bacteria can create an optimal environment for each other by providing essential cofactors(like iron,vitamins,and indole-3-acetic acid),oxygen,dissolved organic matter,and tryptophan.This collaboration leads to effective microbial growth,enhanced N and P removal,and energy generation.The study also uncovers crucial metabolic pathways,functional genes,and patterns of microbial succession.Significantly,the effluent NH4 t-N and P levels complied with the Chinese national Class-II,Class-V,Class-IA,and Class-IB wastewater discharge standards when the HRT was reduced from 15 to 6 h.Optimal results,including the highest rates of CO_(2)fixation(1.23 g L^(-1)),total energy yield(32.35 kJ L^(-1)),and the maximal lipid(33.91%)and carbohydrate(41.91%)content,were observed at an HRT of 15 h.Overall,this study not only confirms the feasibility of CFMBAWTS but also lays a crucial foundation for enhancing our understanding of this technology and propelling its practical application in wastewater treatment plants.展开更多
基金the support of the National Key Research and Development Program (No. 2019YFC0408503)the Project of Thousand Youth Talents (No. AUGA2160100917)。
文摘Recently, the use of microalgae for bioremediation of pharmaceuticals(Ph As) has attracted increasing interest. However, most studies focused more on microalgae removal performance, its defensive response to the Ph As during wastewater treatment remains unexplored. Herein, microalgal three defensive systems have been investigated in synthetic wastewater, with six Ph As as the typical drug. Results show that Ph As could bind to EPS, and this action in turn could help to alleviate the direct toxicity of Ph As to microalgae. Subsequently, the physiological analyses revealed the increase of superoxide dismutase(SOD), catalase(CAT), and peroxidase(POD) activities, potentially reducing the oxidative stress induced by Ph As. Furthermore, the enzyme activities of cytochrome P450(CYP450) and glutathione-S-transferase(GST) were significantly upregulated after exposure to SMX, CIP and BPA, followed by a significant decrease in biodegradation rates after the addition of CYP450 inhibitors, suggesting that the biotransformation and detoxification of Ph As occurred. Meanwhile, molecular docking further revealed that CYP450 could bind with Ph As via hydrogen bond and hydrophobic interaction, which proved their abilities to be metabolized and form transformation products in microalgae. These findings provide an advancing understanding of microalgae technologies to improve the treatment of wastewater contaminated with Ph As.
基金supported by the State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(No.2022TS13)the National Key Research and Development Program(No.2019YFC0408503)the Key Research Program of Wuhan(No.2022022202015015).
文摘Microalgal-indigenous bacterial wastewater treatment(MBWT)emerges as a promising approach for the concurrent removal of nitrogen(N)and phosphorus(P).Despite its potential,the prevalent use of MBWT in batch systems limits its broader application.Furthermore,the success of MBWT critically depends on the stable self-adaptation and synergistic interactions between microalgae and indigenous bacteria,yet the underlying biological mechanisms are not fully understood.Here we explore the viability and microbial dynamics of a continuous flow microalgae-indigenous bacteria advanced wastewater treatment system(CFMBAWTS)in processing actual secondary effluent,with a focus on varying hydraulic retention times(HRTs).The research highlights a stable,mutually beneficial relationship between indigenous bacteria and microalgae.Microalgae and indigenous bacteria can create an optimal environment for each other by providing essential cofactors(like iron,vitamins,and indole-3-acetic acid),oxygen,dissolved organic matter,and tryptophan.This collaboration leads to effective microbial growth,enhanced N and P removal,and energy generation.The study also uncovers crucial metabolic pathways,functional genes,and patterns of microbial succession.Significantly,the effluent NH4 t-N and P levels complied with the Chinese national Class-II,Class-V,Class-IA,and Class-IB wastewater discharge standards when the HRT was reduced from 15 to 6 h.Optimal results,including the highest rates of CO_(2)fixation(1.23 g L^(-1)),total energy yield(32.35 kJ L^(-1)),and the maximal lipid(33.91%)and carbohydrate(41.91%)content,were observed at an HRT of 15 h.Overall,this study not only confirms the feasibility of CFMBAWTS but also lays a crucial foundation for enhancing our understanding of this technology and propelling its practical application in wastewater treatment plants.
