Antibacterial Properties of Peptide and Protein Fractions from Cornu aspersum Mucus.

The discovery and investigation of new natural compounds with antimicrobial activity are new potential strategies to reduce the spread of antimicrobial resistance. The presented study reveals, for the first time, the promising antibacterial potential of two fractions from Cornu aspersum mucus with an MW < 20 kDa and an MW > 20 kDa against five bacterial pathogens-Bacillus cereus 1085, Propionibacterium acnes 1897, Salmonella enterica 8691, Enterococcus faecalis 3915, and Enterococcus faecium 8754. Using de novo sequencing, 16 novel peptides with potential antibacterial activity were identified in a fraction with an MW < 20 kDa. Some bioactive compounds in a mucus fraction with an MW > 20 kDa were determined via a proteomic analysis on 12% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and bioinformatics. High homology with proteins and glycoproteins was found, with potential antibacterial activity in mucus proteins named aspernin, hemocyanins, H-lectins, and L-amino acid oxidase-like protein, as well as mucins (mucin-5AC, mucin-5B, mucin-2, and mucin-17). We hypothesize that the synergy between the bioactive components determined in the composition of the fraction > 20 kDa are responsible for the high antibacterial activity against the tested pathogens in concentrations between 32 and 128 µg/mL, which is comparable to vancomycin, but without cytotoxic effects on model eukaryotic cells of Saccharomyces cerevisiae. Additionally, a positive effect, by reducing the levels of intracellular oxidative damage and increasing antioxidant capacity, on S. cerevisiae cells was found for both mucus extract fractions of C. aspersum. These findings may serve as a basis for further studies to develop a new antibacterial agent preventing the development of antibiotic resistance.

Evaluation of the Biological Activities of Peptides from Epidermal Mucus of Marine Fish Species from Chilean Aquaculture.

The skin of fish is a physicochemical barrier that is characterized by being formed by cells that secrete molecules responsible for the first defense against pathogenic organisms. In this study, the biological activity of peptides from mucus of Seriola lalandi and Seriolella violacea were identified and characterized. To this purpose, peptide extraction was carried out from epidermal mucus samples of juveniles of both species, using chromatographic strategies for purification. Then, the peptide extracts were characterized to obtain the amino acid sequence by mass spectrometry. Using bioinformatics tools for predicting antimicrobial and antioxidant activity, 12 peptides were selected that were chemically produced by simultaneous synthesis using the Fmoc-Tbu strategy. The results revealed that the synthetic peptides presented a random coil or extended secondary structure. The analysis of antimicrobial activity allowed it to be discriminated that four peptides, named by their synthesis code 5065, 5069, 5070, and 5076, had the ability to inhibit the growth of Vibrio anguillarum and affected the copepodite stage of C. rogercresseyi. On the other hand, peptides 5066, 5067, 5070, and 5077 had the highest antioxidant capacity. Finally, peptides 5067, 5069, 5070, and 5076 were the most effective for inducing respiratory burst in fish leukocytes. The analysis of association between composition and biological function revealed that the antimicrobial activity depended on the presence of basic and aromatic amino acids, while the presence of cysteine residues increased the antioxidant activity of the peptides. Additionally, it was observed that those peptides that presented the highest antimicrobial capacity were those that also stimulated respiratory burst in leukocytes. This is the first work that demonstrates the presence of functional peptides in the epidermal mucus of Chilean marine fish, which provide different biological properties when the fish face opportunistic pathogens.

Revealing Metabolic Dysregulation Induced by Polypropylene Nano- and Microplastics in Nile Tilapia via Noninvasive Probing Epidermal Mucus.

A noninvasive sampling technology was conceived, employing a disposable acupuncture needle in conjunction with high-resolution mass spectrometry (termed as noninvasive direct sampling extractive electrospray ionization mass spectrometry, NIDS-EESI-MS) to scrutinize the epidermal mucus of Nile tilapia for insights into the metabolic dysregulation induced by polypropylene nano- and microplastics. This analytical method initiates with the dispensing of an extraction solvent onto the needles coated with the mucus sample, almost simultaneously applying a high voltage to generate analyte ions. This innovative strategy obliterates the necessitation for laborious sample preparation, thereby simplifying the sampling process. Employing this technique facilitated the delineation of a plethora of metabolites, encompassing, but not confined to, amino acids, peptides, carbohydrates, ketones, fatty acids, and their derivatives. Follow-up pathway enrichment analysis exposed notable alterations within key metabolic pathways, including the biosynthesis of phenylalanine, tyrosine, and tryptophan, lysine degradation, as well as the biosynthesis and metabolism of valine, leucine, and isoleucine pathways in Nile tilapia, consequent to increased concentrations of polypropylene nanoplastics. These metabolic alterations portend potential implications such as immune suppression, among other deleterious outcomes. This trailblazing application of this methodology not only spares aquatic life from sacrifice but also inaugurates an ethical paradigm for conducting longitudinal studies on the same organisms, facilitating detailed investigations into the long-term effects of environmental pollutants. This technique enhances the ability to observe and understand the subtle yet significant impacts of such contaminants over time.

In situ pulmonary mucus hydration assay using rotational and translational diffusion of gold nanorods with polarization-sensitive optical coherence tomography.

Significance: Assessing the nanostructure of polymer solutions and biofluids is broadly useful for understanding drug delivery and disease progression and for monitoring therapy. Aim: Our objective is to quantify bronchial mucus solids concentration (wt. %) during hypertonic saline (HTS) treatment in vitro via nanostructurally constrained diffusion of gold nanorods (GNRs) monitored by polarization-sensitive optical coherence tomography (PS-OCT). Approach: Using PS-OCT, we quantified GNR translational (DT) and rotational (DR) diffusion coefficients within polyethylene oxide solutions (0 to 3 wt. %) and human bronchial epithelial cell (hBEC) mucus (0 to 6.4 wt. %). Interpolation of DT and DR data is used to develop an assay to quantify mucus concentration. The assay is demonstrated on the mucus layer of an air-liquid interface hBEC culture during HTS treatment. Results: In polymer solutions and mucus, DT and DR monotonically decrease with increasing concentration. DR is more sensitive than DT to changes above 1.5 wt. % of mucus and exhibits less intrasample variability. Mucus on HTS-treated hBEC cultures exhibits dynamic mixing from cilia. A region of hard-packed mucus is revealed by DR measurements. Conclusions: The extended dynamic range afforded by simultaneous measurement of DT and DR of GNRs using PS-OCT enables resolving concentration of the bronchial mucus layer over a range from healthy to disease in depth and time during HTS treatment in vitro.

Peptide Toxins from Antarctica: The Nemertean Predator and Scavenger Parborlasia corrugatus (McIntosh, 1876).

Peptide toxins from marine invertebrates have found use as drugs and in biotechnological applications. Many marine habitats, however, remain underexplored for natural products, and the Southern Ocean is among them. Here, we report toxins from one of the top predators in Antarctic waters: the nemertean worm Parborlasia corrugatus (McIntosh, 1876). Transcriptome mining revealed a total of ten putative toxins with a cysteine pattern similar to that of alpha nemertides, four nemertide-beta-type sequences, and two novel full-length parborlysins. Nemertean worms express toxins in the epidermal mucus. Here, the expression was determined by liquid chromatography combined with mass spectrometry. The findings include a new type of nemertide, 8750 Da, containing eight cysteines. In addition, we report the presence of six cysteine-containing peptides. The toxicity of tissue extracts and mucus fractions was tested in an Artemia assay. Notably, significant activity was observed both in tissue and the high-molecular-weight mucus fraction, as well as in a parborlysin fraction. Membrane permeabilization experiments display the membranolytic activity of some peptides, most prominently the parborlysin fraction, with an estimated EC50 of 70 nM.

Coarse-grained modeling and dynamics tracking of nanoparticles diffusion in human gut mucus.

The gastrointestinal (GI) tract's mucus layer serves as a critical barrier and a mediator in drug nanoparticle delivery. The mucus layer's diverse molecular structures and spatial complexity complicates the mechanistic study of the diffusion dynamics of particulate materials. In response, we developed a bi-component coarse-grained mucus model, specifically tailored for the colorectal cancer environment, that contained the two most abundant glycoproteins in GI mucus: Muc2 and Muc5AC. This model demonstrated the effects of molecular composition and concentration on mucus pore size, a key determinant in the permeability of nanoparticles. Using this computational model, we investigated the diffusion rate of polyethylene glycol (PEG) coated nanoparticles, a widely used muco-penetrating nanoparticle. We validated our model with experimentally characterized mucus pore sizes and the diffusional coefficients of PEG-coated nanoparticles in the mucus collected from cultured human colorectal goblet cells. Machine learning fingerprints were then employed to provide a mechanistic understanding of nanoparticle diffusional behavior. We found that larger nanoparticles tended to be trapped in mucus over longer durations but exhibited more ballistic diffusion over shorter time spans. Through these discoveries, our model provides a promising platform to study pharmacokinetics in the GI mucus layer.

Aluminum exposure alters the pedal mucous secretions of the chocolate-band snail, Eobania vermiculata (Gastropoda: Helicidae).

Aluminum (Al) is used in everyday life and present in food drugs, packaging, industry, and agriculture. Although it is the most common metal in the Earth crust, a correlation has been demonstrated between its presence and various pathologies, even serious ones, especially of a neurological type. However, there is a histological gap regarding the role Al can have in contact with the covering and secreting epithelia. The alterations of the ventral and dorsal foot mucocytes and their secretions of the snail Eobania vermiculata caused by Al were investigated in situ by histochemical and lectin-histochemical techniques. Administration to different experimental groups took place for 3 and 9 days with 50 and 200 µM of AlCl3. Several types of mucocytes were detected with a prevalent secretion of acid glycans in the foot of E. vermiculata. Sulfated glycans prevail in the dorsal region, with one type showing only fucosylated residues and another also having galactosaminylated and glycosaminylated residues. Carboxylated glycans prevail in the ventral region, with presence of galactosaminylated, glycosaminylated, and fucosylated residuals in both cells. Snails treated presented a general decrease of mucin amount in the secreting cells and affected the mucus composition. These changes could alter the rheological and functional properties of the mucus with possible implications for the health of the treated animals. RESEARCH HIGHLIGHTS: Snails were fed with Al-contaminated lettuce at different concentrations. In the foot mucocytes produced mucus with prevailing acidic glycans. In the treated resulted a reduction in the amount of mucus and an alteration of glycan composition.

Extraction, structure, pharmacological activities and applications of polysaccharides and proteins isolated from snail mucus.

Snail mucus had medical applications for wound healing as early as ancient Greece and the late Han Dynasty (China). A literature search found 165 modern research papers discussing the extraction methods, chemical compositions, pharmacological activities, and applications of snail mucus. Thus, this review summarized the research progress on the extraction, structure, pharmacological activities, and applications of polysaccharides and proteins isolated from snail mucus. The extraction methods of snail mucus include natural secretion and stimulation with blunt force, spray, electricity, un-shelling, ultrasonic-assisted, and ozone-assisted. As a natural product, snail mucus mainly comprises two polysaccharides (glycosaminoglycan, dextran), seven glycoproteins (mucin, lectin), various antibacterial peptides, allantoin, glycolic acid, etc. It has pharmacological activities that encourage cell migration and proliferation, and promote angiogenesis and have antibacterial, anti-oxidative and anticancer properties. The mechanism of snail mucus' chemicals performing antibacterial and wound-healing was proposed. Snail mucus is a promising bioactive product with multiple medical applications and has great potential in the pharmaceutical and healthcare industries. Therefore, this review provides a valuable reference for researching and developing snail mucus.

Gastropod Slime-Based Gel as an Adjustable Synthetic Model for Human Airway Mucus.

Airway mucus works as a protective barrier in the human body, as it entraps pathogens that will be later cleared from the airways by ciliary transport or by coughing, thus featuring the rheological properties of a highly stretchable gel. Nonetheless, the study of these physical barrier as well as transport properties remains limited due to the restricted and invasive access to lungs and bronchi to retrieve mucus and to the poor repeatability inherent to native mucus samples. To overcome these limits, we report on a biobased synthetic mucus prepared from snail slime and multibranched thiol cross-linker, which are able to establish disulfide bonds, in analogy with the disulfide bonding of mucins, and therefore build viscoelastoplastic hydrogels. The gel macroscopic properties are tuned by modifying the cross-linker and slime concentrations and can quantitatively match those of native sputum from donors with cystic fibrosis (CF) or non-cystic fibrosis bronchiectasis (NCFB) both in the small- and large-deformation regimes. Heterogeneous regimes were locally found in the mucus model by passive microrheology, in which both diffusive and non-diffusive motion are present, similar to what is observed in sputa. The biobased synthetic approach proposed in the present study thus allows to produce, with commercially available components, a promising model to native respiratory mucus regarding both mechanical and, to a lesser extent, physicochemical aspects.

Recent advances in mucus-penetrating nanomedicines for oral treatment of colonic diseases.

INTRODUCTION: Oral administration is the most common route for treating colonic diseases that present increased incidences in recent years. Colonic mucus is a critical rate-limiting barrier for the accumulation of oral therapeutics in the colonic tissues. To overcome this obstacle, mucus-penetrating nanotherapeutics have been exploited to increase the accumulated amounts of drugs in the diseased sites and improve their treatment outcomes against colonic diseases. AREAS COVERED: In this review, we introduce the structure and composition of colonic mucus as well as its impact on the bioavailability of oral drugs. We also introduce various technologies used in the construction of mucus-penetrating nanomedicines (e.g. surface modification of polymers, physical means and biological strategies) and discuss their mechanisms and potential techniques for improving mucus penetration of nanotherapeutics. EXPERT OPINION: The mucus barrier is often overlooked in oral drug delivery. The weak mucus permeability of conventional medications greatly lowers drug bioavailability. This challenge can be addressed through physical, chemical and biological technologies. In addition to the reported methods, promising approaches may be discovered through interdisciplinary research that further helps enhance the mucus penetration of nanomedicines.

Standardized Extract from Wastes of Edible Flowers and Snail Mucus Ameliorate Ultraviolet B-Induced Damage in Keratinocytes.

Several studies have highlighted the ability of snail mucus in maintaining healthy skin conditions due to its emollient, regenerative, and protective properties. In particular, mucus derived from Helix aspersa muller has already been reported to have beneficial properties such as antimicrobial activity and wound repair capacity. In order to enhance the beneficial effects of snail mucus, a formulation enriched with antioxidant compounds derived from edible flower waste (Acmella oleracea L., Centaurea cyanus L., Tagetes erecta L., Calendula officinalis L., and Moringa oleifera Lam.) was obtained. UVB damage was used as a model to investigate in vitro the cytoprotective effects of snail mucus and edible flower extract. Results demonstrated that polyphenols from the flower waste extract boosted the antioxidant activity of snail mucus, providing cytoprotective effects in keratinocytes exposed to UVB radiation. Additionally, glutathione content, reactive oxygen species (ROS), and lipid peroxidation levels were reduced following the combined treatment with snail mucus and edible flower waste extract. We demonstrated that flower waste can be considered a valid candidate for cosmeceutical applications due to its potent antioxidant activity. Thus, a new formulation of snail mucus enriched in extracts of edible flower waste could be useful to design innovative and sustainable broadband natural UV-screen cosmeceutical products.

In vitro and ex vivo models for evaluating vaginal drug delivery systems.

Vaginal drug delivery systems are often preferred for treating a variety of diseases and conditions of the female reproductive tract (FRT), as delivery can be more targeted with less systemic side effects. However, there are many anatomical and biological barriers to effective treatment via the vaginal route. Further, biocompatibility with the local tissue and microbial microenvironment is desired. A variety of in vitro and ex vivo models are described herein for evaluating the physicochemical properties and toxicity profile of vaginal drug delivery systems. Deciding whether to utilize organoids in vitro or fresh human cervicovaginal mucus ex vivo requires careful consideration of the intended use and the formulation characteristics. Optimally, in vitro and ex vivo experimentation will inform or predict in vivo performance, and examples are given that describe utilization of a range of methods from in vitro to in vivo. Lastly, we highlight more advanced model systems for other mucosa as inspiration for the future in model development for the FRT.

Digestion Resistance of Soybean 7S Protein and Its Implications for Reinforcing the Gastric Mucus Barrier.

Previous studies have found that soybean protein, especially soybean 7S protein (ß-conglycinin), exhibits digestion resistance, but the mechanism of digestion resistance and its implications for human health are still unclear. Here, we show that the extracted soybean 7S protein contains both oligomer globulins and amyloid aggregates, while the gastric digested soybean 7S protein only contains amyloid aggregates and thus exhibits digestion resistance. An animal experiment shows that un-digestible soybean 7S protein effectively prevents aspirin-induced acute gastric mucosa damage. The impacts of un-digestible soybean 7S protein on gastric mucus barrier properties are investigated using quartz crystal microbalance with dissipation (QCM-D), Langmuir monolayer, and multiple particle tracking (MPT). Results show that these un-digestible protein aggregates can penetrate into gastric mucus, increase the viscosity and compactness of the mucin layer, and reinforce the gastric mucus barrier properties. The findings are helpful to understand that high consumption of non-fermented soybean foods is associated with a decreased risk of gastric cancer.

Emerging role of colorectal mucus in gastroenterology diagnostics.

Colonoscopy is currently the gold standard for diagnosis of inflammatory bowel disease (IBD) and colorectal cancer (CRC). This has the obvious drawback of being invasive as well as carrying a small risk. The most widely used non-invasive approaches include the use of faecal calprotectin in the case of IBD and fecal immunochemical test in the case of CRC. However, the necessity of stool collection limits their acceptability for some patients. Over the recent years, there has been emerging data looking at the role of non-invasively obtained colorectal mucus as a screening and diagnostic tool in IBD and CRC. It has been shown that the mucus rich material obtained by self-sampling of anal surface following defecation, can be used to measure various biomarkers that can aid in diagnosis of these conditions.

Endogenous Fluorescent Proteins in the Mucus of an Intertidal Polychaeta: Clues for Biotechnology.

The vast ocean holds many unexplored organisms with unique adaptive features that enable them to thrive in their environment. The secretion of fluorescent proteins is one of them, with reports on the presence of such compounds in marine annelids being scarce. The intertidal Eulalia sp. is an example. The worm secretes copious amounts of mucus, that when purified and concentrated extracts, yield strong fluorescence under UV light. Emission has two main maxima, at 400 nm and at 500 nm, with the latter responsible for the blue-greenish fluorescence. Combining proteomics and transcriptomics techniques, we identified ubiquitin, peroxiredoxin, and 14-3-3 protein as key elements in the mucus. Fluorescence was found to be mainly modulated by redox status and pH, being consistently upheld in extracts prepared in Tris-HCl buffer with reducing agent at pH 7 and excited at 330 nm. One of the proteins associated with the fluorescent signal was localized in secretory cells in the pharynx. The results indicate that the secretion of fluorescent proteinaceous complexes can be an important defense against UV for this dweller. Additionally, the internalization of fluorescent complexes by ovarian cancer cells and modulation of fluorescence of redox status bears important considerations for biotechnological application of mucus components as markers.

Prediction of Antibacterial Peptides against Propionibacterium acnes from the Peptidomes of Achatina fulica Mucus Fractions.

Acne vulgaris is a common skin disease mainly caused by the Gram-positive pathogenic bacterium, Propionibacterium acnes. This bacterium stimulates the inflammation process in human sebaceous glands. The giant African snail (Achatina fulica) is an alien species that rapidly reproduces and seriously damages agricultural products in Thailand. There were several research reports on the medical and pharmaceutical benefits of these snail mucus peptides and proteins. This study aimed to in silico predict multifunctional bioactive peptides from A. fulica mucus peptidome using bioinformatic tools for the determination of antimicrobial (iAMPpred), anti-biofilm (dPABBs), cytotoxic (ToxinPred) and cell-membrane-penetrating (CPPpred) peptides. Three candidate peptides with the highest predictive score were selected and re-designed/modified to improve the required activities. Structural and physicochemical properties of six anti-P. acnes (APA) peptide candidates were performed using the PEP-FOLD3 program and the four previous tools. All candidates had a random coiled structure and were named APAP-1 ori, APAP-2 ori, APAP-3 ori, APAP-1 mod, APAP-2 mod, and APAP-3 mod. To validate the APA activity, these peptide candidates were synthesized and tested against six isolates of P. acnes. The modified APA peptides showed high APA activity on three isolates. Therefore, our biomimetic mucus peptides could be useful for preventing acne vulgaris and further examined on other activities important to medical and pharmaceutical applications.

Snail Mucus Enhances Chemosensitivity of Triple-negative Breast Cancer Via Activation of the Fas Pathway.

BACKGROUND/AIM: The poor prognosis and chemoresistance of patients with triple-negative breast cancer (TNBC) urge the development of new therapeutic strategies. Snail mucus has shown its ability against inflammation, a process closely related to tumorigenesis, suggesting a potential anti-cancer activity. MATERIALS AND METHODS: The effect and mechanisms of snail mucus on cell viability were determined by IncuCyte Live-cell analysis and molecular biological methods. The anti-cancer fractions of snail mucus were isolated and identified by medium pressure liquid chromatography (MPLC) and nuclear magnetic resonance (NMR) spectrometry analysis. RESULTS: Snail mucus significantly decreased the viability of TNBC cells with relatively lower cytotoxicity to normal breast epithelial cells and enhanced their response to chemotherapy through activation of Fas signaling by suppressing nucleolin. Two peptide fractions have been identified as the anti-cancer ingredients of the snail mucus. CONCLUSION: Snail mucus can induce programmed cell death via the extrinsic apoptotic pathway and has therapeutic potential by achieving a chemo-sensitizing effect in TNBCs.

The effect of biologically active compounds in the mucus of slugs Limax maximus and Arion rufus on human skin cells.

Molluscs are one of the sources of biologically active substances, which are now intensively studied, especially for their anti-cancer properties. Malignant melanoma originates from melanocytes, develops very quickly and is associated with poor prognosis. Therefore, the aim of the study was to assess the properties of biologically active compounds in sterile mucus isolated from slugs Limax maximus and Arion rufus. Tested mucus were isolated using the new self-developed method which is safe for the environment and the animal donors. The impact of the mucus on human keratinocytes CCD 1106 KERTr and malignant melanoma cells A-375 was examined using MTT assay and SRB assay, which allowed us to determine the cell metabolic activity and cell number after treating them with slug mucus isolated from Limax maximus and Arion rufus decreased human keratinocytes and melanoma cells metabolic activity as well as manifested properties of reducing the number of cells in both tested cell lines, and therefore can be a source of biologically active substances with anticancer potential.

Terrestrial snail-mucus mediated green synthesis of silver nanoparticles and in vitro investigations on their antimicrobial and anticancer activities.

Over the past few years, biogenic methods for designing silver nanocomposites are in limelight due to their ability to generate semi-healthcare and para-pharmaceutical consumer goods. The present study reports the eco-friendly synthesis of silver nanoparticles from the hitherto unexplored mucus of territorial snail Achatina fulica by the facile, clean and easily scalable method. The detailed characterization of the resultant samples by UV-Visible Spectroscopy, FESEM-EDS, XRD and FTIR Spectroscopy techniques corroborated the formation of silver nanoparticles in snail mucus matrix. The resultant samples were tested against a broad range of Gram positive and Gram negative bacteria like Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and a fungal strain Aspergillus fumigatus by well diffusion method. The results indicate that silver nanoparticles in mucus matrix exhibit strong antibacterial as well as antifungal activity. The pertinent experiments were also performed to determine the inhibitory concentration against both bacterial and fungal strains. Anticancer activity was executed by in vitro method using cervical cancer cell lines. Curiously, our biogenically synthesized Ag nanoparticles in biocompatible mucus revealed anticancer activity and demonstrated more than 15% inhibition of Hela cells. We suggest an interesting possibility of formulating antimicrobial and possibly anticancer creams/gels for topical applications in skin ailments.

Untargeted analysis of pure snail slime and snail slime-induced Au nanoparticles metabolome with MALDI FT-ICR MS.

Chronic wounds result from the failure of the normal wound healing process. Any delay during the tissue repair process could be defined as chronic wound healing, potentially having a highly detrimental impact on human health. To face this problem, in the last years, the use of different technologies alternative to therapeutic agents is gaining more attention. The Helix aspersa snail slime-based products are increasingly being used for skin injury, thanks to their ability to make tissue repair processes faster. To date, a comprehensive overview of pure snail slime metabolome is not available. Besides, Au nanoparticles (AuNPs) technology is spreading rapidly in the medical environment, and the search for AuNPs "green" synthetic routes that involve natural products as precursor agents is demanded, alongside with a deep comprehension of the kind of species that actively take part in synthesis and product stabilization. The aim of this work is to characterize the metabolic profile of a pure snail slime sample, by an untargeted high-resolution mass spectrometry-based analysis. In addition, insights on AuNPs synthesis and stabilization by the main components of pure snail slime used to induce the synthesis were obtained. The untargeted analysis provided a large list of important classes of metabolites, that is, fatty acid derivatives, amino acids and peptides, carbohydrates and polyphenolic compounds that could be appreciated in both samples of slime, with and without AuNPs. Moreover, a direct comparison of the obtained results suggests that mostly nitrogen and sulfur-bearing metabolites take part in the synthesis and stabilization of AuNPs.