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We report an effective and environmentally sustainable water treatment approach using enzymes encapsulated in biogenic vault nanoparticles. Manganese peroxidase (MnP), whose stability was remarkably extended by encapsulating into vaults, rapidly catalyzed the biotransformation of endocrine-disrupting compounds, including bisphenol A (BPA), bisphenol F (BPF), and bisphenol AP (BPAP). The vault-encapsulated MnP (vMnP) treatment removed 80-95% of each of the tested bisphenols (BPs) at lower enzyme dosage, while free native MnP (nMnP) only resulted in a 19-36% removal, over a 24-h period. Treatment by vMnP and nMnP resulted in considerable disparities in product species and abundance, which were consistent with the observed changes in the estrogenic activities of BPs. To test if vMnP-catalyzed transformations generated toxic intermediates, we assessed biological hallmarks of BP toxicity, namely, the ability to disrupt reproductive processes. The toxicity of vMnP-treated samples, as measured in the model organism, Caenorhabditis elegans, was dramatically reduced for all three BPs, including the reproductive indicators of BPA exposure such as reduced fertility and increased germ cell death. Collectively, our results indicate that the vMnP system represents an efficient and safe approach for the removal of BPs and promise the development of vault-encapsulated customized enzymes for treating other targeted organic compounds in contaminated waters.

The influence of growth medium water chemistry, specifically carbon/nitrogen (C/N) molar ratios, on the characteristics and development of biofilms of the model microorganism Pseudomonas aeruginosa was investigated. C/N = 9 had a unique effect on biofilm composition as well as quorum sensing (QS) pathways, with higher concentrations of carbohydrates and proteins in the biofilm and a significant upregulation of the QS gene lasI in planktonic cells. The effect of C/N ratio on total attached biomass was negligible. Principal component analysis revealed a different behavior of most outputs such as carbohydrates and QS chemicals at C/N = 9, and pointed to correlations between parameters of biofilm formation and steady state distribution of cells and extracellular components. C/N ratio was also shown to influence organic compound utilization by both planktonic and sessile organisms, with a maximum chemical oxygen demand (COD) removal of 83% achieved by biofilms at C/N = 21. Planktonic cells achieved higher COD removal rates, but greater overall rates after six days occurred in biofilms. The development of a dual-species biofilm of P. aeruginosa and Nitrobacter winogradskyi was also influenced by C/N, with increase in the relative abundance of the slower-growing N. winogradskyi above C/N = 9. These results indicate that altering operational parameters related to C/N would be relevant for mitigating or promoting biofilm formation and function depending on the desired industrial application or treatment configuration.

Unlike growth on tissue, microbes can grow freely on implantable devices with minimal immune system intervention and often form resilient biofilms that continuously pump out pathogenic cells. The efficacy of antibiotics used to treat infection is declining due to increased rates of pathogenic resistance. A simple, one-step zwitterionic surface modification is developed to significantly reduce protein and microbial adhesion to synthetic materials and demonstrate the successful modification of several clinically relevant materials, including recalcitrant materials such as elastomeric polydimethylsiloxane. The treated surfaces exhibit robust adhesion resistance against proteins and microorganisms in both static and flow conditions. Furthermore, the surface treatment prevents the adhesion of mammalian fibroblast cells while displaying no cytotoxicity. To demonstrate the clinical efficacy of the novel technology in the real-world, a surface-treated, commercial silicone foley catheter is developed that is cleared for use by the U.S. Food and Drug Administration (K192034). 16long-term catheterized patients received surface-treated catheters and completed a Patient Global Impression of Improvement (PGI-I) questionnaire. 10out of 16patients described their urinary tract condition post implantation as "much better" or "very much better" and 72% (n=13) of patients desire to continue using the surface-treated catheter over conventional latex or silicone catheters.

Microbial enzymes catalyze various reactions inside and outside living cells. Among the widely studied enzymes, fungal enzymes have been used for some of the most diverse purposes, especially in bioremediation, biosynthesis, and many nature-inspired commercial applications. To improve their stability and catalytic ability, fungal enzymes are often immobilized on assorted materials, conventional as well as nanoscale. Recent advances in fungal enzyme immobilization provide effective and sustainable approaches to achieve improved environmental and commercial outcomes. This review aims to provide a comprehensive overview of commonly studied fungal enzymes and immobilization technologies. It also summarizes recent advances involving immobilized fungal enzymes for the degradation or assembly of compounds used in the manufacture of products, such as detergents, food additives, and fossil fuel alternatives. Furthermore, challenges and future directions are highlighted to offer new perspectives on improving existing technologies and addressing unexplored fields of applications.

The application of urban wastewater treatment plants (WWTPs) products to agricultural lands has contributed to the rising level of antibiotic resistance and drawn a critical public health concern. It has not been thoroughly investigated at which spatial scales a biosolid applied area as a potentially predominant source affects surrounding soil resistomes. This study investigated distribution and impact of WWTP biosolids treated with anaerobic digestion on an agricultural area. Heterotrophic plate counts (HPCs) and quantitative polymerase chain reaction (qPCR) were performed for detection of selected antibiotic-resistant bacteria (ARB), selected antibiotic resistance genes (ARGs), intI1 genes, and 16S rRNA genes. Biosolid samples contained significantly higher levels of selected ARGs than the raw agricultural soils (p0.05). The average relative abundances of intI1, sul1, bla

This study presents an eco-friendly and efficient technology, using immobilized enzymes, vault-encapsulated laccases (vlaccase), for decolorization and detoxification of dyes. Vault encapsulation remarkably improved the performance of laccase at industrially relevant conditions, including neutral to alkaline pH and relatively high temperatures. Two representative anthraquinone and azo dyes, Reactive Blue 19 and Acid Orange 7, respectively, were rapidly decolorized (72% and 80%) by vlaccase treatment while natural laccase (nlaccase) achieved 40% and 32% decolorization. The toxicity of treated and untreated dyes was tested on model bacterial, algal, and insect cells. The inhibitory effects of dyes towards selected bacteria were reduced in vlaccase-treated samples. The chlorophyll synthesis in algae was less inhibited by dyes after vlaccase treatment. Furthermore, the toxicity of dye degradation products to insect cells was significantly mitigated in the vlaccase group. Collectively, these results indicate that vlaccase is a stable and strong enzymatic system for removing dyes from waters.

Granular activated carbon (GAC) has been used to remove per- and polyfluoroalkyl substances (PFASs) from industrial or AFFF-impacted waters,but its effectiveness can be low because adsorption of short-chained PFASs is ineffective and its sites are exhausted rapidly by co-contaminants. To increase adsorption of anionic PFASs on GAC by electrostatic attractions,we modified GAC's surface with the cationic polymer poly diallyldimethylammonium chloride (polyDADMAC) and tested its capacity in complex water matrices containing dissolved salts and humic acid. Amending with concentrations of polyDADMAC as low as 0.00025% enhanced GAC's adsorption capacity for PFASs,even in the presence of competing ions. This suggests that electrostatic interactions with polyDADMAC's quaternary ammonium functional groups helped bind organic and inorganic ions as well as the headgroup of short-chain PFASs,allowing more overall PFAS removal by GAC. Evaluating the effect of polymer dose is important because excessive addition can block pores and reduce overall PFAS removal rather than increase it. To decrease the waste associated with this adsorption strategy by making the adsorbent viable for more than one saturation cycle,a regeneration method is proposed which uses low-power ultrasound to enhance the desorption of PFASs from the polyDADMAC- GAC with minimum disruption to the adsorbent's structure. Re-modification with the polymer after sonication resulted in a negligible decrease in the sorbent's capacity over four saturation rounds. These results support consideration of polyDADMAC-modified GAC as an effective regenerable adsorbent for ex-situ concentration step of both short and long-chain PFASs from real waters with high concentrations of competing ions and low PFAS loads.

Per- and polyfluoroalkyl substances (PFASs) are anthropogenic amphipathic heat-resistant materials found in some household products and Aqueous Film-Forming Foams (AFFFs) used to extinguish hydrocarbon fires. There is a critical need for developing destructive technologies for the treatment of PFAS-impacted waters because several PFASs are classified as probable carcinogens and endocrine disruptors. We tested the destruction of 7 individual PFASs, a mix of 24 native PFASs (24Mix), and samples of AFFF and concentrated Investigation Derived Waste (IDW) by high-frequency ultrasound (700 kHz – 1040 W) in deionized water, groundwater containing low total dissolved solids (TDS) (388 mg L−1), and high-TDS groundwater (10.2 g L−1). This study demonstrated the degradation of novel PFASs, hexafluoropropylene oxide dimer acid (HFPO-DA) and 6:2 fluorotelomer sulfonamidoalkyl betaine (6:2 FTAB), with near-stoichiometric fluoride release. The salts and surfactants affect the air-water partitioning coefficients of PFASs and their availability at the ultrasonic cavity, thereby affecting the degradation rates. The degradation rates of sulfonates and short-chain PFASs were 30% to 60% higher in low TDS groundwater than those in deionized water, while the rates were lower in high TDS groundwater. The degradation rates of sulfonates in AFFF were 40% to 60% higher as compared to the 24Mix. The treatment of concentrated, high-TDS IDW resulted in significant defluorination of 41 PFASs, consuming 3 kWh g−1 – 76 kWh g−1 whereas dilute AFFF degradation utilized 5900 kWh g−1. The results inform important parameters for designing and operating ultrasonic reactors for the degradation of PFASs and verify that sonolytic treatment of concentrated PFAS mixtures and AFFF IDWs can effectively degrade and defluorinate PFASs without the formation of disinfection by-products.