Synthesis and antibacterial evaluation of novel psoralen derivatives against methicillin-resistant Staphylococcus aureus (MRSA).

Today, the bacterial infections caused by multidrug-resistant pathogens seriously threaten human health. Thereby, there is an urgent need to discover antibacterial drugs with novel mechanism. Here, novel psoralen derivatives had been designed and synthesized by a scaffold hopping strategy. Among these targeted twenty-five compounds, compound ZM631 showed the best antibacterial activity against methicillin-resistant S. aureus (MRSA) with the low MIC of 1 µg/mL which is 2-fold more active than that of the positive drug gepotidacin. Molecular docking study revealed that compound ZM631 fitted well in the active pockets of bacterial S. aureus DNA gyrase and formed a key hydrogen bond binding with the residue ASP-1083. These findings demonstrated that the psoralen scaffold could serve as an antibacterial lead compound for further drug development against multidrug-resistant bacterial infections.

Discovery of novel oridonin sulfamide derivatives as potent NLRP3 inhibitors by a visible-light photocatalysis-enabled peripheral editing.

The progress of organicsyntheticmethod can promote late-stage lead compound modification and novel active compound discovery. Molecular editing technology in the field of organic synthesis, including peripheral and skeletal editing, facilitates rapid access to molecular diversity of a lead compound. Peripheral editing of CH bond activation is gradually used in lead optimization to afford novel active scaffolds and chemical space exploitation. To develop oridonin derivatives with high anti-inflammatory potency, novel oridonin sulfamides had been designed and synthesized by a scaffoldhopping strategy based on a visible-light photocatalysis peripheral editing. All novel compounds revealed measurable inhibition of IL-1ß and low cytotoxicity in THP-1 cells. The docking study indicated that the best active compound ZM640 was accommodated in thebinding site of NLRP3 with two hydrogen bond interaction. These preliminary results confirm that α, ß-unsaturated carbonyl of oridonin is not essential for NLRP3 inhibitory effect. This new oridonin scaffold has its potential to be further developed as a promising class of NLRP3 inhibitors.

Characterization of a New Laccase from Vibrio sp. with pH-stability, Salt-tolerance, and Decolorization Ability.

Laccases have been widely used for fruit juice clarification, food modification, and paper pulp delignification. In addition, laccases exhibit remarkable performance in the degradation of toxic substances, including pesticides, organic synthetic dyes, antibiotics, and organic pollutants. Thus, the screening and development of robust laccases has attracted significant attention. In this study, Vibrio sp. LA is a strain capable of producing cold-adapted laccases. The laccase coding gene L01 was cloned from this strain and expressed in Yarrowia lipolytica, a host with good secretion ability. The secreted L01 (approximate MW of 56,000 Da) had the activity and specific activity of 18.6 U/mL and 98.6 U/mg toward ABTS, respectively. The highest activity occurred at 35 °C. At 20 °C, L01 activity was over 70% of the maximum activity in pH conditions ranging from 4.5-10.0. Several synthetic dyes were efficiently degraded by L01. Owing to its robustness, salt tolerance, and pH stability, L01 is a promising catalytic tool for potential industrial applications.

Hierarchically porous poly(amidoxime)/bacterial cellulose composite aerogel for highly efficient scavenging of heavy metals.

Developing cheap, green, efficient and renewable adsorbents to address the issue of heavy metal pollution is highly desired for satisfying the requirements of economy sustainability and water security. Herein, a composite aerogel composed of bacterial cellulose (BC) and poly(amidoxime) (PAO) has been fabricated via a facile and scalable self-assembly and in situ oximation transformation for heavy metals removal. Benefiting from the unique three-dimensional (3D) interconnected porous architecture and high density of amidoxime functional moieties, the developed PAO/BC composite aerogel is capable of efficiently sequestrating heavy metals with exceptional sorption capacities, e.g. 571.5 mg g-1 for Pb2+, 509.2 mg g-1 for Cu2+, 494 mg g-1 for Zn2+, 457.2 mg g-1 for Mn2+, and 382.3 mg g-1 for Cd2+, outperforming most reported nano-adsorbents. Meanwhile, the sorption equilibrium for the investigated five heavy metals is achieved within 25 min with high removal efficiencies. Significantly, the developed PAO/BC composite aerogels possess superior reusability performance. Furthermore, the PAO/BC aerogels-packed column can continuously and effectively treat the simulated wastewater with multiple heavy metals coexisting to below the threshold value in the drinking water recommended by World Health Organization (WHO), highlighting its feasibility in the complex environmental water.

Enhanced fluoride removal by hierarchically porous carbon foam monolith with high loading of UiO-66.

Environmental concern associated with excess fluoride has intrigued the unceasing exploration of new multifunctional hybrid materials to mitigate any undesirable consequence to human health. Herein, a novel hybrid monolith has been successfully fabricated via a facile in-situ growth strategy for highly efficient defluoridation from contaminated waters, in which homogeneously dispersed UiO-66 particles are perfectly anchored on three dimensional (3D) porous carbon foam (CF). Benefiting from fully exposed active sites, excellent pore accessibility and efficient mass transport, the integrated UiO-66/CF hybrid monolith exhibits fast adsorption kinetics, and outstanding uptake capacity toward fluoride as high as 295 mg g-1, which greatly outperforms the previously reported adsorbents. Furthermore, the fluoride removal efficiency of the spent monolith can reach up to 70% after four cycles, accompanied by facile separation nature and outstanding water stability. More significantly, the resulting UiO-66/CF packed column (0.36 g) can continuously treat 400 mL of F- solution with 6.2 mg L-1 before the breakthrough point occurs, highlight its potential feasibility for fluoride removal in the practical applicability.

NiFe-Layered Double Hydroxide Nanosheet Arrays Supported on Carbon Cloth for Highly Sensitive Detection of Nitrite.

Excessive uptake of nitrite has been proven to be detrimental to the ecological system and human health. Hence, there is a rising requirement for constructing effective electrochemical sensors to precisely monitor the level of nitrite. In this work, NiFe-layered double hydroxide nanosheet arrays (NiFe-LDH NSAs) have been successfully fabricated on a carbon cloth (CC) substrate via a facile one-pot hydrothermal route. By integrating the collective merits of macroporous CC and NiFe-LDH NSAs such as superior electrical conductivity, striking synergistic effect between the dual active components, enlarged electrochemically active surface area, unique three-dimensional hierarchical porous network characteristics, and fast charge transport and ion diffusion, the proposed NiFe-LDH NSAs/CC architecture can be served as a self-supporting sensor toward nitrite detection. As a consequence, the resulting NiFe-LDH NSAs/CC electrode demonstrates superior nitrite sensing characteristics, accompanied by broad linear range (5-1000 µM), quick response rate (ca. 3 s), ultralow detection limit (0.02 µM), and high sensitivity (803.6 µA·mM-1·cm-2). Meanwhile, the electrochemical sensor possesses timeless stability, good reproducibility, and strong anti-interference feature. Importantly, the resulting sensor can determine nitrite level in tap and lake water with high recoveries, suggesting its feasibility for practical applications. These findings show that the obtained NiFe-LDH NSAs/CC electrode holds great prospect in highly sensitive and specific detection of nitrite.