Photoactive nano-confined Pt in titania nanotubes (Pt-TiNT) via microwave-assisted flow synthesis

Pt-TiNT with PtO nanoparticles dispersed within the lumen and interlayer spaces of titania nanotubes (TiNT) were prepared by a new process involving titanate nanosheets (TiNS) synthesis in an optimized microwave-assisted flow reactor, followed by ion-exchange with a Pt precursor, before triggering the titanate layer rolling to trap the Pt precursor clusters inside the titania nanotubes, followed by a thermal treatment. TEM, XRD, and Raman analyses confirm the total conversion of TiO2 into TiNS in 15 min at 120 °C and 4 bar, and the TiNS transformation into 181 nm-long TiNT with 10 and 6 nm outer and inner diameter, respectively. The 2% Pt-TiNT comprises 0.7 nm PtO clusters (according to XPS), causing slight distortions of the interlayer spaces, while a few larger 2–3 nm Pt clusters reside within the lumen. As a result, Pt-TiNT is 14-fold more active than TiNT for visible light (400–780 nm) photocatalytic oxidation of diclofenac under 2136 μW·cm−2 irradiation, and>1000-fold better than the uncatalyzed photoconversion reaction under 100 mW·cm−2 artificial solar lighting. In addition, nano-confinement of PtO clusters narrowed the bandgap of the TiNT, which, combined with its excellent absorptivity to harvest light, allowed a broader spectral range of photon energies to activate the photocatalyst. © 2023 Elsevier B.V.This work is supported by the Horizon 2020 BIORIMA project and the Hong Kong Research Grant Council E-HKUST601/17 and in part by the Project of Hetao Shenzhen-Hong Kong University of Science and Technology Innovation Cooperation Zone (HZQB-KCZYB-2020083). Dr. Y.J. Luo stay at the Instituto de Cat´alisis y Petroleoquímica is supported by the HKUST Overseas Research Award. Finally, the authors acknowledge the support of the Central Facilities of the Hong Kong University of Science and Technology including the Material Characterization and Preparation Facility (MCPF) and the Environmental Central Facility (ENVF).Supplementary data to this article can be found online at https://doi. org/10.1016/j.cej.2023.143254Peer reviewe

Lifestyle Evolution And Peroxidase Diversity In Agaricales As Revealed By Comparative Genomics

Descripción de 1 páginas de la comunicación oral presentada en Oxizymes2022 10th edition of the international “Oxizymes” meeting. Siena, Italy, July 5-8, 2022Basidiomycetes of the class Agaricomycetes have developed complex enzymatic machineries that allow them to decompose plant polymers, including lignin. Within this group, saprotrophic Agaricales are characterized by an unparalleled diversity of habitats and lifestyles in comparison with fungi from other orders. With the aim of shedding light on the evolution of lignocellulose-decaying lifestyles in Agaricales we conducted a comparative analysis of 52 Agaricomycetes genomes [1]. This study revealed that Agaricales possess a large diversity of hydrolytic and oxidative enzymes. Surprisingly, computer-assisted gene-family evolution analysis of these enzymes revealed that a few oxidoreductase families showed significantly higher evolutionary rates. Based on these gene families we reconstructed the lifestyles of the ancestors that led to the extant lignocellulose-decomposing Agaricomycetes. According to this, we determined that changes in the oxidative enzymatic toolkit of ancestral Agaricales correlate with the evolution of their ability to grow not only on wood, but also on leaf and grass litter and decayed wood. In this context, the aboye families were analyzed and special attention was paid to peroxidases as a central component of the enzymatic toolkit of saprotrophic Agaricomycetes responsible for lignin degradation. We identified a widespread presence of new ligninolytic peroxidase types in Agaricales, some of them not previously identified in this order, and others also not found in woodrottingPolyporales and other orders of Agaricomycetes. Peroxidase evolution was analyzed in Agaricomycetes by ancestral sequence reconstruction and several major evolutionary pathways were unveiled. The study of the newly identified peroxidases will provide insight into their role in the lignin degradation process. In fact, these studies have already been initiated with the expression and characterization of the first lignin peroxidase identified in Agaricales. [1] Ruiz-Dueñas FJ, Barrasa JM, Sánchez-García M, Camarero S, Miyauchi S, Serrano A, et al., 2021, Mol Biol Evol, 38, 1428-1446.Projects/contracts BI02017-86559-R, BI02015-7369-JIN, AGL2014-55971-R, NSFgrant-1457721 , CEFOX-031 B0831 S, PIE-201620E081 , ANR-11-LABX-0002-01 , US-DOE-DE-AC02-05CH11231N

Phytogrowth- and photosynthesis-inhibiting properties of nostoclide analogues

Six nostoclide analogues were synthesised from 3-benzyl-2(5H)-furanone in one step, with yields ranging from 10 to 71%, and subjected to several biological assays. The two most active of these, 5d and 5e, were shown to be phytogrowth inhibitors of the radicle of Lolium multiflorum Lam, while enhancing the root growth of Physalis ixocarpa Brot. Both compounds inhibited electron flow (basal, phosphorylating and uncoupled) from water to methylviologen (MV); both acted as Hill reaction inhibitors, since the synthesis of ATP was prevented. The uncoupled electron transport from photosystem II (PSII) (water to 2,6-dichlorophenol-indophenol (DPIP)) and photosystem I (PSI) (2,6-dichlorophenol-indophenol reduced (DPIPred) to MV) was inhibited with 500 µM of 5d by 22 and 14% respectively. In addition, 400 µM of 5d inhibited PSI (from tetramethyl-p-benzohydroquinone (TMQH2) to MV) by 40%. Thus 5d inhibited electron transport at the b6f complex. Finally, 500 µM of 5e inhibited electron flow (basal and phosphorylating) by 25%, and 300 µM of 5e enhanced light-activated membrane-bound Mg2+-ATPase by 66%. Thus 5e behaved as a weak Hill reaction inhibitor and an uncoupler. In general, the phytotoxicity of the synthetic lactones was only weakly related to inhibition of photosynthesis. Copyright © 2006 Society of Chemical Industr