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Improper waste disposal or inadequate wastewater treatment can result in pharmaceuticals reaching water bodies, posing environmental hazards. In this study, crude extracts containing the laccase enzyme from Pleurotus florida , Pleurotus eryngii , and Pleurotus sajor caju were used to degrade the fluoroquinolone antibiotics (FQs) levofloxacin (LEV), norfloxacin (NOR), ciprofloxacin (CIP), ofloxacin (OFL), and enrofloxacin (ENR) in aqueous solutions. The results for the fungi derived laccase extracts were compared with those obtained using commercially sourced laccase. Proteomics analysis of the crude extracts confirmed the presence of laccase enzyme across all three tested species, with proteins matching those found in Trametes versicolor and Pleurotus ostreatus. In vivo studies were conducted using species pure lines of fungal whole cells. The highest degradation efficiency observed was 77.7% for LEV in the presence of P. sajor caju after 25 days of treatment. Degradation efficiencies ranged from approximately 60-72% for P. florida , 45–76% for P. eryngii , and 47–78% for P. sajor caju. A series of in vitro experiments were also conducted using crude extracts from the three species and outcomes compared with those obtained when commercial laccase was used confirmed laccase as the enzyme responsible for antibiotic removal. The degradation efficiencies in vitro surpassed those measured in vivo , ranging from approximately 91-98% for commercial laccase, 77–92% for P. florida , 76–92% for P. eryngii , and 78–88% for P. sajor caju. Liquid chromatography–high-resolution mass spectrometry (LC-MS/MS) identified the degradation products, indicating a consistent enzymatic degradation pathway targeting the piperazine moiety common to all tested FQs, irrespective of the initial antibiotic structure. Phytoplankton toxicity studies with Dunaliella tertiolecta were performed to aid in understanding the impact of emerging contaminants on ecosystems, and by-products were analysed for ecotoxicity to assess treatment efficacy. Laccase-mediated enzymatic oxidation shows promising results in reducing algal toxicity, notably with Pleurotus eryngii extract achieving a 97.7% decrease for CIP and a 90% decrease for LEV. These findings suggest the potential of these naturally sourced extracts in mitigating antibiotic contamination in aquatic ecosystems. [Display omitted] • Pleurotus extracts efficiently degrade fluoroquinolone antibiotics, achieving up to 77.7% removal for levofloxacin. • In vitro , Pleurotus extracts outperform whole cells, demonstrating degradation efficiencies of 77–92%. • LC-MS/MS confirms consistent enzymatic degradation pathways across all tested antibiotics. • Pleurotus extracts significantly reduce algal toxicity, with up to 97.7% decrease observed for ciprofloxacin. • Proteomic analysis validates the presence of the laccase enzyme, indicating a promising role in environmental remediation. [ABSTRACT FROM AUTHOR]

Phosphatidylethanolamine (PtdEtn) is a major phospholipid in mammals. It is synthesized via two pathways, the CDP-ethanolamine pathway in the endoplasmic reticulum and the phosphatidylserine (PtdSer) decarboxylase (PSD) pathway in the mitochondria. While the CDP-ethanolamine pathway is considered the major route for PtdEtn synthesis in most mammalian tissues, little is known about the importance of the PSD pathway in vivo, especially in tissues enriched with mitochondria such as skeletal muscle. Therefore, we aimed to examine the role of the mitochondrial PSD pathway in regulating PtdEtn homeostasis in skeletal muscle in vivo. To determine the functional significance of this pathway in skeletal muscle in vivo , an adeno-associated viral vector approach was employed to knockdown PSD expression in skeletal muscle of adult mice. Muscle lipid and metabolite profiling was performed using mass spectrometry. PSD knockdown disrupted muscle phospholipid homeostasis leading to an ∼25% reduction in PtdEtn and an ∼45% increase in PtdSer content. This was accompanied by the development of a severe myopathy, evident by a 40% loss in muscle mass as well as extensive myofiber damage as shown by increased DNA synthesis and central nucleation. In addition, PSD knockdown caused marked accumulation of abnormally appearing mitochondria that exhibited severely disrupted inner membrane integrity and reduced OXPHOS protein content. The PSD pathway has a significant role in maintaining phospholipid homeostasis in adult skeletal muscle. Moreover, PSD is essential for maintenance of mitochondrial integrity and skeletal muscle mass. • The PSD pathway has an important role in regulating muscle phospholipid homeostasis. • Disrupting the PSD pathway caused marked muscle wasting and myofibre damage. • Knockdown of PSD caused accumulation of mitochondria with ultrastructural defects. • PSD is important in regulating mitochondrial integrity and skeletal muscle mass. [ABSTRACT FROM AUTHOR]

Highlights: [•] Na2SeO3 irrigation increased Se content in Agaricus bisporus caps and stalks. [•] Incorporation of Se into mushroom proteins in caps and stalks were also increased. [•] LC–ESI-MS identified SeCys as the major selenoamino acid in the selenoproteins. [•] Incorporation of SeCys into proteins also increased with selenite irrigation. [Copyright &y& Elsevier]

Abstract: Leaf material from nine Ni hyperaccumulating species was collected in New Caledonia: Homalium kanaliense (Vieill.) Briq., Casearia silvana Schltr, Geissois hirsuta Brongn. & Gris, Hybanthus austrocaledonicus Seem, Psychotria douarrei (G. Beauvis.) Däniker, Pycnandra acuminata (Pierre ex Baill.) Swenson & Munzinger (syn Sebertia acuminata Pierre ex Baill.), Geissois pruinosa Brongn. & Gris, Homalium deplanchei (Viell) Warb. and Geissois bradfordii (H.C. Hopkins). The elemental concentration was determined by inductively-coupled plasma optical emission spectrometry (ICP-OES) and from these results it was found that the species contained Ni concentrations from to 250–28,000mg/kg dry mass. Gas chromatography mass spectrometry (GC–MS)-based metabolite profiling was then used to analyse leaves of each species. The aim of this study was to target Ni-binding ligands through correlation analysis of the metabolite levels and leaf Ni concentration. Approximately 258 compounds were detected in each sample. As has been observed before, a correlation was found between the citric acid and Ni concentrations in the leaves for all species collected. However, the strongest Ni accumulator, P. douarrei, has been found to contain particularly high concentrations of malonic acid, suggesting an additional storage mechanism for Ni. A size exclusion chromatography separation protocol for the separation of Ni-complexes in P. acuminata sap was also applied to aqueous leaf extracts of each species. A number of metabolites were identified in complexes with Ni including Ni-malonate from P. douarrei. Furthermore, the levels for some metabolites were found to correlate with the leaf Ni concentration. These data show that Ni ions can be bound by a range of small molecules in Ni hyperaccumulation in plants. [Copyright &y& Elsevier]

Antibiotic proliferation in the environment and their persistent nature is an issue of global concern as they induce antibiotic resistance threatening both human health and the ecosystem. Antibiotics have therefore been categorized as emerging pollutants. Fluoroquinolone (FQs) antibiotics are an emerging class of contaminants that are used extensively in human and veterinary medicine. The recalcitrant nature of fluoroquinolones has led to their presence in wastewater, effluents and water bodies. Even at a low concentration, FQs can stimulate antibacterial resistance. The main sources of FQ contamination include waste from pharmaceutical manufacturing industries, hospitals and households that ultimately reaches the wastewater treatment plants (WWTPs). The conventional WWTPs are unable to completely remove FQs due to their chemical stability. Therefore, the development and implementation of more efficient, economical, convenient treatment and removal technologies are needed to adequately address the issue. This review provides an overview of the technologies available for the removal of fluoroquinolone antibiotics from wastewater including adsorptive removal, advanced oxidation processes, removal using non-carbon based nanomaterials, microbial degradation and enzymatic degradation. Each treatment technology is discussed on its merits and limitations and a comparative view is presented on the choice of an advanced treatment process for future studies and implementation. A discussion on the commercialization potential and eco-friendliness of each technology is also included in the review. The importance of metabolite identification and their residual toxicity determination has been emphasized. The last section of the review provides an overview of the policy interventions and regulatory frameworks that aid in retrofitting antibiotics as a central key focus contaminant and thereby defining the discharge limits for antibiotics and establishing safe manufacturing practices. [Display omitted] • Advanced technologies to remove antibiotic residues from environment is reviewed. • Metabolites and importance of studying their residual toxicity is emphasized. • Modelling approach to establish PNEC as ETP discharge limit has been discussed. • Policy interventions needed to control unmonitored antibiotic release is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Targeted liquid chromatography–mass spectrometry (LC–MS) technology using size exclusion chromatography and metabolite profiling based on gas chromatography–mass spectrometry (GC–MS) were used to study the nickel-rich latex of the hyperaccumulating tree Sebertia acuminata. More than 120 compounds were detected, 57 of these were subsequently identified. A methylated aldaric acid (2,4,5-trihydroxy-3-methoxy-1,6-hexan-dioic acid) was identified for the first time in biological extracts and its structure was confirmed by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. After citric acid, it appears to be one of the most abundant small organic molecules present in the latex studied. Nickel(II) complexes of stoichiometry NiII:acid=1:2 were detected for these two acids as well as for malic, itaconic, erythronic, galacturonic, tartaric, aconitic and saccharic acids. These results provide further evidence that organic acids may play an important role in the transport and possibly in the storage of metal ions in hyperaccumulating plants. [Copyright &y& Elsevier]

One of the major barriers to the mass industrial utilisation of brown seaweeds as food sources stem from the food safety risks associated with their iodine and arsenic concentrations, which typically exceed regulatory limits. Hydrothermal treatments might effectively reduce the high iodine and arsenic concentration of Phyllospora comosa below the Australian maximum residual limits (iodine = 1 mg/g and arsenic = 0.00667 mg/g; dry weight) set for brown seaweeds. The experimental hydrothermal treatments dictated that the 82 °C–250 s treatment reduced the iodine concentration from 2.76 mg/g to 0.88 mg/g (68% reduction) and arsenic concentration from 0.01693 mg/g to 0.00965 mg/g (43% reduction). Machine learning models predicted that blanching at 100 °C for ∼4 minutes will reduce the arsenic concentration below its maximum residual limit. Additive log-ratio transformations showed that around 50% (dw) of the hydrothermally treated Phyllospora comosa samples were leached out during the highest treatment intensity, 82 °C–250 s. Even though, a half of the biomass is lost, hydrothermally treated Phyllospora comosa products are safer for human consumption and thus may permit the expansion of seaweed production and consumption in Australia. [Display omitted] • Hydrothermal blanching reduces iodine concentration of P. comosa below 1 mg/g MRL. • Hydrothermal blanching reduces the arsenic concentration by 43%. • MLM predicts 100 °C–4 min blanching may assure the nutritional safety of P. comosa. • A 100 °C - 11 min blanching may reduce iodine concentrations to the levels of nori. [ABSTRACT FROM AUTHOR]

Highlights: [•] Reducing end (RE) sequence(s) of wheat (monocot) endosperm AXs. [•] β-d-Xylp-(1→4)-[α-l-Araf-(1→3)](+/−)-β-d-Xylp-(1→4)-[α-l-Araf-(1→3)](+/−)-β-d-Xylp. [•] β-d-Xylp-(1→4)-[α-l-Araf-(1→3)](+/−)-β-d-Xylp-(1→4)-[α-d-GlcAp-(1→2)]-β-d-Xylp. [ABSTRACT FROM AUTHOR]

Abstract: Olive leaf supplement was characterised by HPLC and administered to healthy young adults over 28d (three tablets or equivalent liquid dose per day), or in a single bolus dose of three tablets (or liquid equivalent). Oleuropein was the major biophenol in the extracts. There are no data on the excretion of urinary end-products of the metabolism of the olive leaf biophenols. Following both chronic and acute ingestion neither oleuropein, nor its hydrolysis product, hydroxytyrosol, were detected in urine samples. However, glucuronic acid conjugates, derived from oleuropein aglycone were detected in all urine samples up to 6h following acute ingestion. The data suggest that oleuropein is bioavailable, which is a necessary pre-condition for bioactivity. [Copyright &y& Elsevier]

This study provides a comprehensive investigation on the impact of increasing NaCl concentrations on hydroponically grown Stevia rebaudiana cultivars (Shoutian-2 and Fengtian). Growth parameters including plant height, biomass and physiological responses including osmotic potential were measured. In addition, the levels of steviol glycosides, elements and primary metabolites were measured and statistically evaluated. The cultivar Fengtian grew faster, accumulated less Na + and compatible organic solutes, and more K + in the leaves, as compared to the cv. Shoutian-2. Metabolite analysis identified 81 differentially accumulated metabolites, indicating an alteration in the metabolite phenotype of both cultivars upon exposure to salinity A general increase in many amino acids, amines, sugars and sugar phosphates with a concurrent decrease in most organic acids; including tricarboxylic acid (TCA) cycle intermediates, was observed. In the more salt tolerant cv. Fengtian, the levels of hexose phosphates and metabolites involved in cellular protection increased in response to salinity. These metabolites remained unchanged in the sensitive cv. Shoutian-2. Interestingly, salt treatment notably increased the rebaudioside A concentration by 53% while at the same time stevioside decreased by 38% in Fengtian which has important implications for controlling the relative amounts of reboudioside A and stevioside. The findings of this study leads to the conclusion that mild salinity stress can increase the yield of sweetener compounds, which is dependent on the cultivar and the level of salinity stress. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) are key components for the capture of microplastics (MPs) before they are released into natural waterways. Removal efficiencies as high as 99% may be achieved but sub-micron MPs as well as nanoplastics have been overlooked because of analytical limitations. Furthermore, short MP fibres are of concern because of their low capture rate as well as the lack of understanding of their influence on purification system efficiency. This study has investigated the impact of poly(ethylene terephthalate) (PET) short nanofibres on the performance of polyvinylidene fluoride (PVDF) ultrafiltration membranes during cross-flow operation. Model MP fibres with an average length of 10 ± 7 μm and a diameter of 142 ± 40 nm were prepared via a combination of electrospinning and fine cutting using a cryomicrotome. The manufactured MPs were added to both pure and synthetic domestic wastewater at a concentration of 1 mg.L−1 to determine their impact on the performance of PVDF ultrafiltration membranes. The results show that PET fibres attach to the membrane in a disorganised manner with low pore coverage. The water flux was decreased by 8% for MPs in pure water and no noticeable effect in wastewater after 3 days of filtration. Additionally, the nutrient removal efficiency of the membrane was not altered by the presence of PET MPs. These findings show that MP fibres do not significantly influence the early stages of filtration for a standard concentration of MPs in wastewater treatment plant studies. [Display omitted] • PET MP fibres had a limited impact on the water flux during water and wastewater ultrafiltration. • PET fibres rapidly accumulated at the surface of the membrane. • MP fibres could not efficiently cover membranes pores because of their stacking and steric repulsion. • Pollutants removal efficiency was not influenced by PET fibres. • Modelling provided a semi-quantitative description of the fouling behaviour of MPs. [ABSTRACT FROM AUTHOR]