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The presence of antibiotic residues in water is linked to the emergence of antibiotic resistance globally and necessitates novel decontamination strategies to minimize antibiotic residue exposure in both the environment and food. A holistic assessment of cold atmospheric pressure plasma technology (CAPP) for β-lactam antibiotic residue removal is described in this study. CAPP operating parameters including plasma jet voltage, gas composition and treatment time were optimized, with highest β-lactam degradation efficiencies obtained for a helium jet operated at 6 kV. Main by-products detected indicate pH-driven peroxidation as a main mechanism of CAPP-induced decomposition of β-lactams. No in vitro hepatocytotoxicity was observed in HepG2 cells following exposure to treated samples, and E. coli exposed to CAPP-degraded β-lactams did not exhibit resistance development. In surface water, over 50% decrease in antibiotic levels was achieved after only 5 min of treatment. However, high dependence of treatment efficiency on residue concentration, pH and presence of polar macromolecules was observed.

Additional file 1 Table S1. Composition of S. cordifolia aqueous fractions (SCAF). Table S2. Primers sequences (forward and reverse) used for quantification of cytokine mRNA expression in splenocytes and RAW246.7 macrophage cell line. Table S3: MIC and MBC (mg/ml) of Sephadex LH-20 fractions (SCMEXBu) compared to crude methanol extract (MEX). Fig. S1. (A) Typical melt curve for murine inducible nitric oxide synthase (iNOS) (B) Amplification curve of iNOS following incubation of RAW 264.7 cells with SCAF 5 showing untreated control versus treatment with SCAF 5. (C) Amplification for IL-6 following incubation of splenocytes with SCAF 5. Lines show untreated control versus treatment with SCAF 5. Fig. S2. Mass Spectrum of SC2 (A) Mass Fragmentation patterns obtained for SC2 were suggestive of rosmarinic acid. (B) 13C NMR spectra of SC2. (C) Table summarising chemical shifts of both 13C NMR and 1H NMR spectra for SC2. 13C NMR and 1H NMR shifts and proposed structure of SC2 were highly suggestive of rosmarinic acid. (D) The proposed structure of SC2 (rosmarinic acid). Fig. S3. Mass Spectrum of SC1 (A) Mass Fragmentation patterns obtained for SC1 were suggestive of rosmarinic acid 4-O-��-d-glucoside (Rosmarinyl glucoside). (B) 13C NMR spectra of SC1. (C) Table summarising chemical shifts of both 13C NMR, and 1H NMR. 13C NMR, and 1H NMR shifts were highly suggestive of rosmarinic acid 4-O-��-d-glucoside. and the (D) proposed structure of SC1 (rosmarinic acid 4-O-��-d-glucoside).

Large regions of Earth's surface are underlain by salt deposits that evaporated from ancient oceans and are populated by extreme halophilic microbes. Some of these halophiles may have been preserved over geological timescales within hypersaline fluid inclusions, but ingresses of water and/or anthropogenic activities can lead to the formation of alternative habitats, including NaCl stalactites or speleothems. While the microbiology of ancient evaporites has been well-studied, the ecology of these recently formed structures is less-well understood. Here, the microbiology of a NaCl stalactite ('salticle') in a Triassic halite mine is characterised. The specific aims were to: determine the presence of fluid inclusions; determine the microbial structure of the salticle compared with a nearby brine-pool and surficial soil; and characterise the ecophysiological capabilities of this unique ecosystem. The salticle contained fluid inclusions, and their microbiome was composed of Euryarchaetota, Proteobacteria, and Actinobacteria, with Haloarchaea in greater abundance than brine-pool or soil microbiomes. The salticle metagenome exhibited a greater abundance of genes involved in osmoregulation, anaerobic respiration, UV resistance, oxidative stress, and stress-protein synthesis relative to the soil microbiome. We discuss the potential astrobiological implications of salticles as enclosed salt-saturated habitats that are protected from ionising radiation and have a stable water-activity. This article is protected by copyright. All rights reserved.