2021-07-01, Corvini, Philippe, Hou, Ziang, Chu, Jiangfeng, Liu, Cong, Wang, Jinnan, Li, Aimin, Lin, Tong

Photocatalytic denitrification has attracted great attention owing to its high efficiency and environmentally friendly features. However, selectively photocatalytic reduction of high concentration nitrate to N2 is still a challenging problem due to the competition of photons between nitrate and photocatalysts. Herein, the Ag/SiO2 core encapsulated in the crystalline TiO2 shell (Ag/SiO2@cTiO2) was constructed for improvement of photocatalytic denitrification. Finite difference time domain (FDTD) simulation demonstrated that strong light scattering improved light harvesting via optical confinement. Meanwhile, surface plasmon resonance and electron sink effect of Ag not only enhanced the photogenerated electrons density but also promoted charge carriers separation of Ag/SiO2@cTiO2. More importantly, ecb− of TiO2-shell could be immediately transferred to Ag to keep the balance between Ag0 and Ag+, which contributed to the good stability of Ag/SiO2@cTiO2. 95.8% nitrate (C0 = 2000 mg/L) was removed by 5 wt%Ag/SiO2@cTiO2 with N2 selectivity of 93.6% within 4 h. Even after five cycles, 5 wt%Ag/SiO2@cTiO2 still remained high photocatalytic denitrification efficiency (92.2%). Notably, since TiO2-shell prevented the reaction between Ag and Cl−, more than 92% nitrate could be removed within 5.3 h in the presence of high concentration Cl−.

2021-03-02, Corvini, Philippe, Qi, Mengyuan, Liang, Bin, Ma, Xiaodan, Yan, Lei, Dong, Wenchen, Kong, Deyong, Zhang, Liying, Zhu, Haizhen, Gao, Shu-Hong, Jiang, Jiandong, Liu, Shuan-Jiang, Wang, Aijie

Microbial communities are believed to outperform monocultures in the complete catabolism of organic pollutants via reduced metabolic burden and increased robustness to environmental challenges; however, the interaction mechanism in functional microbiomes remains poorly understood. Here, three functionally differentiated activated sludge microbiomes (S1: complete catabolism of sulfamethoxazole (SMX); S2: complete catabolism of the phenyl part of SMX ([phenyl]-SMX) with stable accumulation of its heterocyclic product 3-amino-5-methylisoxazole (3A5MI); A: complete catabolism of 3A5MI rather than [phenyl]-SMX) were enriched. Combining time-series cultivation-independent microbial community analysis, DNA-stable isotope probing, molecular ecological network analysis, and cultivation-dependent function verification, we identified key players involved in the SMX degradation process. Paenarthrobacter and Nocardioides were primary degraders for the initial cleavage of the sulfonamide functional group (-C-S-N- bond) and 3A5MI degradation, respectively. Complete catabolism of SMX was achieved by their cross-feeding. The co-culture of Nocardioides, Acidovorax, and Sphingobium demonstrated that the nondegraders Acidovorax and Sphingobium were involved in the enhancement of 3A5MI degradation. Moreover, we unraveled the internal labor division patterns and connections among the active members centered on the two primary degraders. Overall, the proposed methodology is promisingly applicable and would help generate mechanistic, predictive, and operational understanding of the collaborative biodegradation of various contaminants. This study provides useful information for synthetic activated sludge microbiomes with optimized environmental functions.

2020-01-13, Diaconu, Mariana, Corvini, Philippe, Lenz, Markus

2018-07, Woźniak-Karczewska, Marta, Cvancarová, Monika, Chrzanowski, Łukasz, Corvini, Philippe, Cichocka, Danuta

The consumption of nootropic drugs has increased tremendously in the last decade, though the studies on their environmental fate are still scarce. Nootropics are bioactive compounds designed to alter human's physiology therefore the adverse effects towards wildlife can be expected. In order to understand their environmental impact, the knowledge on their transformation pathways is necessary. Methylphenidate belongs to the most prescribed neuro-enhancers and is among the most favored smart drugs used in non-medical situations. It is metabolized in human liver and excreted as ritalinic acid. Here, we showed for the first time that ritalinic acid can be biodegraded and used as a sole carbon and nitrogen source by various microbial strains originating from different environmental samples. Five axenic strains were isolated and identified as: Arthrobacter sp. strain MW1, MW2 and MW3, Phycicoccus sp. strain MW4 and Nocardioides sp. strain MW5. Our research provides the first insight into the metabolism of ritalinic acid and suggests that it may differ depending on the strain and growth conditions, especially on availability of nitrogen. The isolates obtained in this study can serve as model organisms in further studies on the catabolism of ritalinic acid and methylphenidate but potentially also other compounds with similar structures. Our findings have important implication for the sewage epidemiology. We demonstrated that ritalinic acid is subject to quick and efficient biodegradation thus its use as a stable biomarker should be reconsidered.

2021-05-25, Rosetti, Simona, Corvini, Philippe, Majone, Mauro

2021, Nazemi, Seyed, Olesinska, Magdalena, Pezzella, Cinzia, Varriale, Simona, Lin, Chia-Wei, Corvini, Philippe, Shahgaldian, Patrick

We report a method of glycosylated enzymes’ surface immobilisation and stabilisation. The enzyme is immobilised at the surface of silica nanoparticles through the reversible covalent binding of vicinal diols of the enzyme glycans with a surface-attached boronate derivative. A soft organosilica layer of controlled thickness is grown at the silica surface, entrapping the enzyme and thus avoiding enzyme leaching. We demonstrate that this approach results not only in high and durable activity retention but also enzyme stabilisation.

2019-06, Corvini, Nora, Corvini, Philippe, Shahgaldian, Patrick, El Idrissi, Mohamed, Dimitriadou, Eleni

Facile chemical modification of mesoporous silica particles allows the production of gated reservoir systems capable of hydrophobicity-triggered release. Applied to the delivery of nutrients specifically to an oil phase, the systems developed have been shown to reliably assist the bacterial degradation of hydrocarbons. The gated system developed, made of C18 hydrocarbon chains, is demonstrated to be in a closed collapsed state in an aqueous environment, yet opens up through solvation by lipophilic alkanes and releases its content on contact with the oil phase.

2021-03-21, Corvini, Philippe, Songfeng, Wang, Xuan, Wu, Rong, Guo, Wang, Qilin, Guo, Hongyan, Sun, Feifei, Ji, Rong

Soil contamination with tetrabromobisphenol A (TBBPA) has been an environmental concern for many years, but in situ studies of the fate and potential risk of TBBPA are lacking. In this study, we investigated the dissipation, metabolism, strong alkali-hydrolytic (SAH-TBBPA), and vertical movement of TBBPA in the field with and without rice-wheat rotation and reed growth for 1225 days. After 342 days of incubation, 21.3% of the TBBPA remained in the surface soil accompanied by obvious leaching to deeper soil layers in the first 92 days. By day 1225, TBBPA was nearly absent from the surface soil layer. A very low amount of SAH-TBBPA (2.31–3.43 mg/kg) was detected during the first 342 days of incubation. In the surface soil, five metabolites were identified that represented four interconnected pathways: oxidative skeletal cleavage, O-methylation, type II ipso-substitution, and reductive debromination. Both rice–wheat rotation and monocultural reed growth accelerated TBBPA removal in the field by stimulating the anaerobic debromination and aerobic O-methylation, especially the oxidative skeletal cleavage of TBBPA in the rhizosphere soil. Though far from comprehensive, our study investigated the natural attenuation and metabolism of TBBPA in situ and the influence by crops to estimate the environmental risk of TBBPA in a field scale.

2021, Ke, Zhuang, Obamwonyi, Osagie, Kolvenbach, Boris, Ji, Rong, Liu, Shuangjiang, Jiang, Jiandong, Corvini, Philippe

A plethora of organic pollutants such as pesticides, polycyclic and halogenated aromatic hydrocarbons, and emerging pollutants, such as flame retardants, is continuously being released into the environment. This poses a huge threat to the society in terms of environmental pollution, agricultural product quality, and general safety. Therefore, effective removal of organic pollutants from the environment has become an important challenge to be addressed. As a consequence of the recent and rapid developments in additive manufacturing, 3D bioprinting technology is playing an important role in the pharmaceutical industry. At the same time, an increasing number of microorganisms suitable for the production of biomaterials with complex structures and functions using 3D bioprinting technology, have been identified. This article briefly discusses the principles, advantages, and disadvantages of different 3D bioprinting technologies for pollutant removal. Furthermore, the feasibility and challenges of developing bioremediation technologies based on 3D bioprinting have also been discussed

2018-12, Reis, Ana C., Cvancarova Småstuen, M., Liu, Ying, Lenz, Markus, Hettich, Timm, Kolvenbach, Boris, Corvini, Philippe, Nunes, Olga C.

In the last decade, biological degradation and mineralization of antibiotics have been increasingly reported feats of environmental bacteria. The most extensively described example is that of sulfonamides that can be degraded by several members of Actinobacteria and Proteobacteria. Previously, we reported sulfamethoxazole (SMX) degradation and partial mineralization by Achromobacter denitrificans strain PR1, isolated from activated sludge. However, further studies revealed an apparent instability of this metabolic trait in this strain. Here, we investigated this instability and describe the finding of a low-abundance and slow-growing actinobacterium, thriving only in co-culture with strain PR1. This organism, named GP, shared highest 16S rRNA gene sequence similarity (94.6–96.9%) with the type strains of validly described species of the genus Leucobacter. This microbial consortium was found to harbor a homolog to the sulfonamide monooxygenase gene (sadA) also found in other sulfonamide-degrading bacteria. This gene is overexpressed in the presence of the antibiotic, and evidence suggests that it codes for a group D flavin monooxygenase responsible for the ipso-hydroxylation of SMX. Additional side reactions were also detected comprising an NIH shift and a Baeyer–Villiger rearrangement, which indicate an inefficient biological transformation of these antibiotics in the environment. This work contributes to further our knowledge in the degradation of this ubiquitous micropollutant by environmental bacteria.