Excretion Research Articles

Physiological responses of euryhaline marine fish to naturally-occurring hypersalinity

Hypersaline habitats are generally defined as those with salinities in excess of 40 ppt. Well-known hypersaline regions (e.g. salt and soda lakes) have a well-earned reputation for being among the most inhospitable habitats in the world, and fish endemic to these areas have been the subject of much research related to extremophile physiology. Yet, marine coastal hypersalinity is both a common occurrence and a growing consideration in many marine coastal ecosystems, in part owing to human influence (e.g. evaporation, river diversion, desalination effluent). Importantly, any increase in salinity will elevate the osmoregulatory challenges experienced by a fish, which must be overcome by increasing the capacity to imbibe and absorb water and excrete ions. While great attention has been given to dynamic osmoregulatory processes with respect to freshwater to seawater transitions, and to the extreme hypersalinity tolerance that is associated with the adoption of an osmo-conforming strategy, relatively little focus has been placed on the physiological implications of moderate hypersalinity exposures (e.g. ≤ 60 ppt). Importantly, these exposures often represent the threshold of osmoregulatory performance owing to energetic constraints on ion excretion and efficiency limitations on water absorption. This review will explore the current state of knowledge with respect to hypersalinity exposure in euryhaline fishes, while placing a particular focus on the physiological constraints, plasticity and downstream implications of long-term exposure to moderate hypersalinity.

Progress in drug therapy of Wilson's disease

Wilson's disease, also known as hepatolenticular degeneration, is an inherited disorder of copper metabolism caused by homozygous or compound heterozygous variants in the ATP7B gene, which is mainly clinically manifested as liver disease and/or neurological/psychological disorders, and Kayser-Fleischer ring in the peripheral cornea. Patients with Wilson's disease are currently treated with lifelong use of chelating agents that promote copper ion excretion and/or zinc agents that reduce copper absorption, but there is still an unmet clinical need because some patients who receive treatment have poor efficacy, disease progression, or serious adverse drug reactions. In recent years, new therapeutic drugs have been developed rapidly. This article will summarize the advances in drug treatment of Wilson's disease, shedding new light on the treatment of Wilson's disease.

Evidence of Human-designated Antiretroviral (ARV) Drug Residues in Broiler Chicken, Domestic Pigs, and Animal Feeds in Tanzania.

Recent reports have indicated the use of antiretroviral (ARV) drugs to boost animal production in neighboring Uganda, with further reports of use in several African countries. This cross-sectional study was conducted in nine districts in Tanzania, and involved screening for the presence of three first-line ARVs (lamivudine, nevirapine, and efavirenz) residues in the muscle and blood of domestic pigs and broiler chickens, and in sampled animal feed and water. Residues were determined using liquid chromatography and mass spectrometry (LC-MS/MS). The method involved calibration of the lower limit of quantitation (LLOQ) and limit of detection (LOD). ARVs were detected and quantified using the Multiple Reaction Monitoring (MRM) system. 131 (66.8%) of the 196 samples of muscle, blood, and animal feed were found to contain lamivudine residues, with the highest concentration detected in domestic pig blood and muscle (7.58mg/kg) and the lowest concentration (0.01 mg/kg) in broiler chicken feed. There was a significant relationship between the presence of lamivudine by sample type and sample origin (p=0.000). Nevirapine and efavirenz drugs were not detected in any of the collected samples. No ARV residues were detected in water samples (n=37). This study confirms the use of ARVs in animal production in Tanzania as evidenced by the presence of residues in animal feeds. We found lamivudine residues in domestic pigs and broiler chickens at concentrations higher than those recently reported in other East African studies. Farmers living with HIV may be using ARVs from their prescribed medications, which may lead to poor adherence and the emergence of drug resistance. Besides direct human and animal health issues, these residues in animal feeds and animal excreta can lead to environmental contamination leading to several negative impacts. We recommend a total ban on human-designated ARVs in animal production and advocate for comprehensive studies and monitoring systems across African countries to reveal potential societal and other reasons for their use and provide comprehensive solutions using One Health approaches.

Saline-alkali soil amended with biochar derived from maricultural-solid-waste: Ameliorative effect and mechanism

At present, it is estimated that approximately 800 million hectares of arable land worldwide is saline-alkali soil, which has become one of the major limiting factors restricting global agricultural productivity. Meanwhile, the residual food and excreta of mariculture animals, accompanied by potential eutrophication pollution, remain an unresolved issue due to salinity. In this study, the ameliorative effects of biochar (BC700) prepared from maricultural-solid-waste on the biological properties and physicochemical of saline-alkali soil and Salicornia europaea L growth were investigated. Supplements of 1, 3 and 5% BC700 significantly increased the total nitrogen, available phosphorus, available potassium and organic carbon in soil by 2.00–68.30%, 26.74–64.96%, 7.74–52.53% and 3.43–64.96%, respectively. And BC700 significantly reduced soil pH. This occurred with enhanced soil urease, sucrase and alkaline phosphatase activities and alterations to the bacterial community structure, thus improving P and N cycling and the soil physicochemical properties. In addition, BC700 has weakened the competition between saline soil microorganisms and also changed the key species of microbial networks. Co-utilization of BC700 and S. europaea cultivation could increase the stability of the soil microbial community while the growth of the plant was significantly promoted by 19.8–25.4%. Supplements of 3% BC700 are recommended as an eco-friendly and effective treatment for the recycling of mariculture wastes for the improvement of saline-alkali soils.

Fluid Ejections in Nature.

From microscopic fungi to colossal whales, fluid ejections are universal and intricate phenomena in biology, serving vital functions such as animal excretion, venom spraying, prey hunting, spore dispersal, and plant guttation. This review delves into the complex fluid physics of ejections across various scales, exploring both muscle-powered active systems and passive mechanisms driven by gravity or osmosis. It introduces a framework using dimensionless numbers to delineate transitions from dripping to jetting and elucidate the governing forces. Highlighting the understudied area of complex fluid ejections, this review not only rationalizes the biophysics involved but also uncovers potential engineering applications in soft robotics, additive manufacturing, and drug delivery. By bridging biomechanics, the physics of living systems, and fluid dynamics, this review offers valuable insights into the diverse world of fluid ejections and paves the way for future bioinspired research across the spectrum of life.

The role of ruminant urine and faeces in the recycling of nutrients by forages

This study addresses the effect of using animal excreta on the nutritional content of forages, focusing on macro- and micro-element concentrations (nitrogen; N, phosphorus; P, sulphur; S, copper; Cu, zinc; Zn, manganese; Mn, selenium; Se) from animal feed to excreta, soil, and plants. Data were collected from pot and field trials using separate applications of sheep or cattle urine and faeces. Key findings indicate that soil organic carbon (SOC) and the type of excreta significantly influences nutrient uptake by forages, with varied responses among the seven elements defined above. Although urine contributes fewer micronutrients compared to faeces (as applied at a natural volume/mass basis, respectively), it notably improves forage yield and micronutrient accumulation, thus potentially delivering positive consequences at the farm level regarding economic performance and soil fertility when swards upon clayey soil types receive said urine in temperate agro-climatic regions (i.e., South West England in the current context). In contrast, faeces application in isolation hinders Se and Mn uptake, once again potentially delivering unintended consequences such as micronutrient deficiencies in areas of high faeces deposition. As it is unlikely that (b)ovine grazing fields will receive either urine or faeces in isolation, we also explored combined applications of both excreta types which demonstrates synergistic effects on N, Cu, and Zn uptake, with either synergistic or dilution effects being observed for P and S, depending largely on SOC levels. Additionally, interactions between excreta types can result in dilution or antagonistic effects on Mn and Se uptake. Notably, high SOC combined with faeces reduces Mn and Se in forages, raising concerns for grazed ruminant systems under certain biotic situations, e.g., due to insufficient soil Se levels typically observed in UK pastures for livestock growth. These findings underscore the importance of considering SOC and excreta nutritional composition when designing forage management to optimize nutrient uptake. It should be noted that these findings have potential ramifications for broader studies of sustainable agriculture through system-scale analyses, as the granularity of results reported herein elucidate gaps in knowledge which could affect, both positively and negatively, the interpretation of model-based environmental impact assessments of cattle and sheep production (e.g., in the case of increased yields [beneficial] or the requirement of additional synthetic supplementation [detrimental]).

Nitrogen and phosphorus budgets of the bullfrog (Aquarana catesbeiana) in different body weights

Aquaculture water eutrophication is primarily driven by nitrogen (N) and phosphorus (P), partly derived from animal excretions. Understanding the N and P metabolism is crucial for mitigating environmental pollution caused by aquaculture. This study investigated N and P budgets in bullfrogs (Aquarana catesbeiana) of varying body weights: 52.63 ± 0.33 (50 g), 98.64 ± 0.55 (100 g), 159.97 ± 0.58 (150 g) and 250.01 ± 2.61 (250 g). Our findings highlighted the significant influence of body size on N and P budgets in bullfrogs. As body weight increased, feed intake rate, N and P intake rates, growth rate, N and P growth rates, N and P metabolism rates, feces rate, while the N and P feces rates all decreased. The relationship between each index and body weight was expressed as a power function (Y = aWb). The N and P budget equations for bullfrogs were established as follows: 100 Intake N (IN) = 30.75 Growth N (GN) + 62.48 Metabolism N (MN) + 2.10 Feces N (FN) + 4.67 Others (ON), and 100 P Intake P (IP) = 74.16 Growth P (GP) + 4.18 Metabolism P (MP) + 7.92 Feces P (FP) + 13.75 Others (OP). In conclusion, daily feeding per body weight of bullfrog should be reduced as their body weight increased. Consequently, the dietary protein should be progressively lowered to minimize nitrogen waste, while bullfrogs demonstrated effective utilization of P in the soybean meal diet.

Reduction in antimicrobial resistance in a watershed after closure of livestock farms

Natural environments play a crucial role in transmission of antimicrobial resistance (AMR). Development of methods to manage antibiotic resistance genes (ARGs) in natural environments are usually limited to the laboratory or field scale, partially due to the complex dynamics of transmission between different environmental compartments. Here, we conducted a nine-year longitudinal profiling of ARGs at a watershed scale, and provide evidence that restrictions on livestock farms near water bodies significantly reduced riverine ARG abundance. Substantial reductions were revealed in the relative abundance of genes conferring resistance to aminoglycosides (42%), MLSB (36%), multidrug (55%), tetracyclines (53%), and other gene categories (59%). Additionally, improvements in water quality were observed, with distinct changes in concentrations of dissolved reactive phosphorus, ammonium, nitrite, pH, and dissolved oxygen. Antibiotic residues and other pharmaceuticals and personal care products (PPCPs) maintain at a similarly low level. Microbial source tracking demonstrates a significant decrease in swine fecal indicators, while human fecal pollution remains unchanged. These results suggest that the reduction in ARGs was due to a substantial reduction in input of antibiotic resistant bacteria and genes from animal excreta. Our findings highlight the watershed as a living laboratory for understanding the dynamics of AMR, and for evaluating the efficacy of environmental regulations, with implications for reducing environmental risks associated with AMR on a global scale.

Gill transcriptomes analysis of Takifugu obscurus, Takifugu rubripes and their hybrid offspring in freshwater and seawater

Osmoregulation is essential for aquatic organisms to balance their internal fluids and ions and adapt to environmental changes. The gills are a crucial organ for maintaining osmotic balance in fish by regulating the uptake and excretion of ions. Changes in the salinity of the aquatic environment can lead to alterations in the expression of genes within gill cells, which helps to maintain the internal salinity balance and allows the fish to adapt to different salinity levels. In this study, we used transcriptomic data of the gill from the euryhaline Takifugu obscurus and the stenohaline Takifugu rubripes, as well as their hybrid offspring (Tor1 and Tor2), to investigate how the gill contributes to osmoregulation in response to freshwater and seawater. Our study revealed 8 commonly differentially expressed genes among these four fish species. Analysis of the T. obscurus transcriptome data has demonstrated that SLC1a5, a member of the solute carrier (SLC) family, and Gper1, a G-protein coupled estrogen receptor 1-like, are enriched in many biological processes and might be important for its osmoregulation in freshwater. Furthermore, PDE8B, Lrrc9 and Cplx4 might be important osmoregulatory genes that are inherited by offspring in T. obscurus. Moreover, upon encountering changes in water salinity, T. rubripes and the hybrid offspring Tor1 reveal a marked concentration of differentially expressed genes in metabolic pathways within their gills, whereas T. obscurus and the hybrid offspring Tor2 show a more even distribution of DEGs across various signaling pathways. Finally, the Pearson correlation analysis revealed that the T. rubripes displayed a significant correlation with Tor1, while the T. obscurus was significantly related to Tor2. Overall, this study provides a theoretical foundation for understanding the salinity adaptation mechanisms in hybrid offspring of Takifugu, and holds significant implications for guiding the breeding of economically valuable Takifugu strains with improved traits.

Raman spectroscopy assisted by other analytical techniques to identify the most deteriorated carbonate‐stones to be consolidated in two monuments of Vitoria‐Gasteiz (Spain)

AbstractThis work describes the diagnostic study on the building materials, mostly carbonated, belonging to Santa Maria Cathedral and the Medieval Wall of Vitoria‐Gasteiz (Spain) with the aim to design the best conservation procedure. Both the studies of the lithology and the secondary compounds originated by environmental impacts on the Cathedral and on the Medieval Wall were carried out using laboratory instruments (μ‐Raman and micro‐energy‐dispersive X‐ray spectroscopy, X‐ray diffraction and ion chromatography) on selected samples provided by the restorers. The systematic presence of black crusts in the stones of the Cathedral was related to the growth of microcrystalline structures of secondary compounds and biological patinas and the deposition of atmospheric particles from traffic and house heating systems. In fact, the main components identified were carbon, and iron compounds such as hematite, goethite, magnetite and lepidocrocite. In addition, the detection of lead compounds (lead‐rich hydroxyapatite) suggested in the same way the impact of the urban environment on the degradation and blackening of stone materials. The presence of sulfates, mainly gypsum, and, to a lesser extent, epsomite, anhydrite and bloedite could be caused by the sulfation of carbonated compounds as a result of an acid attack of atmospheric pollutants. The results on the secondary products of the Medieval Wall showed a greater presence of degradation by microorganisms compared to the Cathedral. This is probably related to the large garden surrounding the fortification, where the grass is in direct contact to the lower part of the structure. Markers of biological activity, such as carotenoid pigments and calcium oxalate weddellite, together with other soluble oxalates were identified. The presence of ammonium nitrate, characterised by means ion chromatography, causes a chemical degradation of carbonate stone materials over time, due to the acidic nature of the ammonium ion. In both cases considered in this study, the presence of nitrate compounds, nitratine and potassium nitrate, was attributed to both natural factors (ammonium nitrate is coming from the decomposition of plant and animal excretions), and anthropogenic contamination.

Molecular determinants of olfactory receptor activation: Comparative analysis of Olfr205 and Olfr740 family member responses to indole

Indole is widely present in nature and contributes significantly to the smell of flowers and animal excretion. However, the odor perception mechanism for indole is unclear, despite previous reports suggesting that it activates the Olfr740 family of receptors. In this study, we successfully identified another receptor, Olfr205, that is responsive to indole. Molecular model construction and binding pocket analysis predicted that the A202 residue in transmembrane helix 5 of Olfr205 forms a crucial hydrogen bond with indole, facilitating receptor activation. Additionally, G112 in transmembrane helix 3 of the Olfr740 family is involved in indole activation of receptors. Finally, our mutant function assay showed that substitution of A202 in Olfr205 and G112 in Olfr740 with other amino acids significantly decreased the receptor response to indole, which provides robust evidence to confirm the docking results. In summary, our study is the first to reveal that Olfr205 is an olfactory receptor distinct from those in the Olfr740 family that is activated by indole. Moreover, these receptors display different indole-binding mechanisms. This study sheds light on molecular binding mechanisms and contributes to a deeper understanding of indole perception.

Zoonotic Disease Risk Perception and Infection Control Practices amongst Veterinarians in Kerala, India

Abstract Introduction: Veterinarians could act as the sentinel for the study of zoonotic diseases. This study evaluates the prevalence of zoonoses amongst Kerala veterinarians and explores infection control measures they use to protect themselves and the factors influencing their infection control practices. Materials and Methods: It is a quantitative cross-sectional study using proportionate sampling with a self-administered questionnaire. Results: About 31.1% of veterinarians experienced symptoms of zoonotic diseases, with dermatophytosis being the most common. Handling tissues, bodily fluids and excretions of animals were the highest risk-carrying procedures. However, the majority of respondents did hand wash, whereas some never properly disposed of used needles. Factors such as heat stress, comfort, cost and time of consultation discouraged one-fourth of participants from using personal protective equipment. Conclusion: Failure to follow infection control practices contributes to the prevalence of zoonoses amongst veterinarians in Kerala. Reasons for this failure include the absence of better policies to address veterinarian’s issues. There is a need for more effective enforcement of infection control policy for the veterinarians.

Water Purification Using Choline-Amino Acid Ionic Liquids: Removal of Amoxicillin.

Antibiotics are the main active pharmaceutical ingredients (APIs) for the treatment and prevention (prophylaxis) of bacterial infections, for which they are essential for health preservation. However, depending on the target bacterial strain, an efficient treatment may imply weeks of continuous intake of antibiotics, whose unmetabolized fraction ends up in the wastewater system by human and animal excreta. The presence of these chemical compounds in wastewater is known to damage aquatic ecosystems and cause antibiotic resistance of pathogenic agents, which threatens the future application of these medicines. Aqueous two-phase systems (ATPSs), an emergent extraction technology for biomolecules such as proteins and vitamins, could provide more eco-friendly and cost-effective extractive alternatives given their nontoxicity and low energetic requirements. Moreover, choline-amino acid ([Ch][AA]) ionic liquids (also known as CAAILs or ChAAILs) are considered one of the greenest classes of ionic liquids due to their favorable biocompatibility, biodegradability, and ease of chemical synthesis. In this work, partition studies of amoxicillin were performed in three ATPSs containing dipotassium hydrogen phosphate (K2HPO4) and the CAAILs (cholinium l-alaninate, [Ch][Ala]; cholinium glycinate, [Ch][Gly]; and cholinium serinate, [Ch][Ser]) at 298.15 K and 0.1 MPa. To better characterize the extract and reduce errors in quantification, the effect of pH on the intensity and stability of the UV-vis spectra of amoxicillin was studied prior to the partition studies, and computational chemistry was used to validate the molecular structure of the synthesized ionic liquids. During experimental determinations, it was observed that the extraction of amoxicillin was favored by less polar ionic liquids, achieving maximum partition coefficients (K) and extraction efficiencies (E) of K = (16 ± 6)·101 and E / % = 97 ± 2, respectively, for {[Ch][Gly] (1) + K2HPO4 (2) + Water (3)} in the longest tie-line.

Soil aggregation and surface‐soil properties under grazed pastures and other conservation land uses in Virginia

AbstractGrazed pastures supporting ruminant livestock have not been well characterized for soil health condition. However, growing interest in holistic management of compromised watersheds suggests that grazing lands deserve more attention for their capacity to provide ecosystem services. Relatively little is known about how grazing management affects soil aggregation and other surface‐soil properties on private lands in the eastern United States. This study investigated the effects of land use (conventional‐till cropland, no‐till cropland, grassland, and woodland) and pasture management characteristics on soil aggregation, bulk density, sieved soil density, total soil N, and soil‐test biological activity on 31 private farms distributed across the western half of Virginia. Soil stability index followed the order (p < 0.05): conventional‐till cropland (0.60 mm mm−1) < no‐till cropland (0.78 mm mm−1) < woodland (0.85 mm mm−1) = grassland (0.89 mm mm−1). Surface soil characteristics improved with pasture age due to organic matter recycling from residual forage mass and animal excreta. Increases in total soil N and soil‐test biological activity helped create water‐stable aggregation and reduce soil bulk density. Soil stability index was optimized with moderate stocking rate of 0.5–1.1 Mg live weight ha−1. Stocking method did not affect soil aggregation or bulk density. Soil stability index declined with increasing N fertilization rate. Soil aggregation characteristics were generally not affected by organic amendment, quantity of hay fed on farm, or occasional hay harvest from pastures, likely because aggregation was high across management variables. Well‐managed grazed pastures in Virginia are creating desirable conservation agricultural land uses to protect watershed quality.

Pharmacoinformational, gerontoinformational and chemoreactomic analysis of the molecule of citrulline malate, carnitine, sulbutiamine and meldonium to identify the molecular mechanisms of antiasthenic action

The pathophysiology of asthenia is very complex and is associated with chronic kidney disease, heart failure, chronic obstructive pulmonary disease, sarcopenia, bacterial and viral pathogens, micronutrient nutritional imbalances, hypothyroidism, etc. Asthenia can occur with excessive (for a given patient) physical, mental or mental stress and adaptation disorders or be iatrogenic in nature (in particular, due to taking medications that contribute to increased loss of vitamins and microelements), incl. due to unwanted drug interactions. The complex nature of the pathophysiology of asthenia necessitates the use of a differentiated approach aimed at eliminating the main cause of asthenia in a given patient. If asthenia is associated primarily with disorders of energy metabolism, then the pathophysiological treatment is the use of nutrients that support intracellular synthesis - such as citrulline, citrulline malate, the main mechanisms of action of which are supporting the urea cycle, increasing the excretion of ammonium ions, reducing the concentration lactate in the blood. The paper presents the results of a comparative pharmacoinformatic and chemoreactomic analysis of citrulline, citrulline malate (CM), carnitine, sulbutiamine and meldonium. The profile of pharmacological effects of citrulline/CM was significantly different from the profiles of other molecules. For citrulline/CM, cholinergic, antidepressant, and lipid-modifying effects have been identified and an antiasthenic effect has been suggested when used in the treatment of Duchenne muscular dystrophy and for disorders of carbohydrate metabolism. Unlike other molecules, CM and carnitine do not contribute to the loss of vitamins and minerals. Inhibition of the CM serotonin 5HT3A receptor may improve vestibulation because blockers of 5-HT3 receptors concentrated in neurons of the vestibular apparatus, improves tests of balance and walking in an experiment in mice. A positive dose-dependent effect of citrulline and CM on the lifespan of a number of model organisms has been shown. Chemoreactomic analysis of molecular receptor proteins indicated new molecular mechanisms of the antiasthenic action of CM: inhibition of serotonin receptors, calcium sensor protein receptors, chemokine receptors, lipopolysaccharides (toll receptors), nociceptin, glutamate, orexin, purines and prostanoids, biosynthesis of NF-kB and TNFα.

Effects of sex and hydration status on kappa opioid receptor-mediated diuresis in rats.

Understanding the function of the kappa opioid receptor (KOP) is crucial for the development of novel therapeutic interventions that target KOP for the treatment of pain, stress-related disorders and other indications. Activation of KOP produces diuretic effects in rodents and man. Sex is a vital factor to consider when assessing drug response in pre-clinical and clinical studies. In this study, the diuretic effect of the KOP agonist, U50488 (1-10 mg/kg), was investigated in both adult female and male Wistar rats that were either normally hydrated or water-loaded. The KOP antagonist norbinaltorphimine (norBNI, 10 mg/kg) was administered 24 h prior to U50488 to confirm the involvement of KOP. U50488 elicited a significant diuretic response at doses ≥ 3 mg/kg in both female and male rats independent of hydration status. U50488 diuretic effects were inhibited by norBNI pre-administration. Water-loading reduced data variability for urine volume in males, but not in females, compared with normally hydrated rats. Sex differences were also evident in U50488 eliciting a significant increase in sodium and potassium ion excretion only in males. This may suggest different mechanisms of U50488 diuretic action in males where renal excretion mechanisms are directly affected more than in females.

A critical and comprehensive review of the current status of 17β-estradiol hormone remediation through adsorption technology.

Even at low concentrations, steroid hormones pose a significant threat to ecosystem health and are classified as micropollutants. Among these, 17β-estradiol (molecular formula: C18H24O2; pKa = 10.46; Log Kow = 4.01; solubility in water = 3.90mgL-1 at 27°C; molecular weight: 272.4gmol-1) is extensively studied as an endocrine disruptor due to its release through natural pathways and widespread use in conventional medicine. 17β-estradiol (E2) is emitted by various sources, such as animal and human excretions, hospital and veterinary clinic effluents, and treatment plants. In aquatic biota, it can cause issues ranging from the feminization of males to inhibiting plant growth. This review aims to identify technologies for remediating E2 in water, revealing that materials like graphene oxides, nanocomposites, and carbonaceous materials are commonly used for adsorption. The pH of the medium, especially in acidic to neutral conditions, affects efficiency, and ambient temperature (298K) supports the process. The Langmuir and Freundlich models aptly describe isothermal studies, with interactions being of a low-energy, physical nature. Adsorption faces limitations when other ions coexist in the solution. Hybrid treatments exhibit high removal efficiency. To mitigate global E2 pollution, establishing national and international standards with detailed guidelines for advanced treatment systems is crucial. Despite significant advancements in optimizing technologies by the scientific community, there remains a considerable gap in their societal application, primarily due to economic and sustainable factors. Therefore, further studies are necessary, including conducting batch experiments with these adsorbents for large-scale treatment along with economic analyses of the production process.

Localizing Isomerized Residue Sites in Peptides with Tandem Mass Spectrometry.

Isomerized amino acid residues have been identified in many peptides extracted from tissues or excretions of humans and animals. These isomerized residues can play key roles by affecting biological activity or by exerting an influence on the process of aging. Isomerization occurs spontaneously and does not result in a mass shift. Thus, identifying and localizing isomerized residues in biological samples is challenging. Herein, we introduce a fast and efficient method using tandem mass spectrometry (MS) to locate isomerized residues in peptides. Although MS2 spectra are useful for identifying peptides that contain an isomerized residue, they cannot reliably localize isomerization sites. We show that this limitation can be overcome by utilizing MS3 experiments to further evaluate each fragment ion from the MS2 stage. Comparison at the MS3 level, utilizing statistical analyses, reveals which MS2 fragments differ between samples and, therefore, must contain the isomerized sites. The approach is similar to previous work relying on ion mobility to discriminate MS2 product ions by collision cross-section. The MS3 approach can be implemented using either ion-trap or beam-type collisional activation and is compatible with the quantification of isomer mixtures when coupled to a calibration curve. The method can also be implemented in combination with liquid chromatography in a targeted approach. Enabling the identification and localization of isomerized residues in peptides with an MS-only methodology will expand accessibility to this important information.

Insights into Agricultural Soil Contamination by a Veterinary Antibiotic TYLOSIN Through Continuous Run-Off Conditions

ABSTRACT Broad-spectrum veterinary antibiotic tylosin (TYL) is utilized in livestock and poultry. Due of its extensive usage and animal excretion in urine and feces, it affects the environment and human health. For determining the equilibrium time, the adsorption maximum capacity and the optimal isotherm model, adsorption batch tests have been conducted. Sips and Pseudo-second order models had R2 values of 0.9937 and 0.9764, respectively, and best matched experimental isotherm and kinetic data. The maximum TYL uptake onto soil was 2355.08 mg.kg−1. Using fixed bed adsorption experiments, the current study clarifies the issue of soil contamination in conditions that are close to natural phenomena. Fixed bed adsorption tests demonstrated that the inlet TYL concentration, soil bed height, and flow rate, influenced saturation and breakthrough times. Bohart-Adams, Thomas, and Yoon-Nelson models matched the experimental findings well in a variety of conditions. With 100 mg.L−1 concentration, 4 cm bed height, and 5 mL.min−1 flow rate, the maximal bed capacity of 1277.06 mg.kg−1 was achieved with R2 value of 0.9797. Experimental findings also indicated that the adsorption capacity in batch and dynamic tests are of the same range of magnitude. Based on this, tylosin is a probable soil contaminant.

Development of a simple UPLC-MS/MS method coupled with a modified QuEChERS for analyzing multiple antibiotics in vegetables and applied to pollution assessment

Antibiotics used in livestock husbandry can contaminate the environment through animal excretions and aquaculture wastewater. Absorption of these antibiotics by vegetables may pose health risks to humans through the food chain. However, research on detecting multi-antibiotics in vegetables remains limited. This study aims to develop a reliable and sensitive method to quantify 72 antibiotics from six classes in vegetable samples using modified QuEChERS and UPLC-MS/MS methods. The QuEChERS method was optimized by investigating extraction solvents, salting-out agents, and adsorbents. The percentage recovery of the 72 analyte antibiotics from spiked vegetable samples ranged between 61.5% and 117.8%. Intra-day and inter-day precision were below 12.1% and 15.4%, respectively. The limits of detection and quantification were 0.010–0.232 µg.kg−1 and 0.032–0.772 µg.kg−1, respectively. The method demonstrated a weak matrix effect for 61.1% of the tested compounds. Applying the developed method to analyze 248 vegetable samples, 15 antibiotics were detected, ranging from 0.010 µg.kg−1 to 561.0 µg.kg−1 fresh weight. Notably, bean sprouts showed the presence of multiple antibiotics, suggesting the possible misuse of antibiotics in their production.