## 1 Introduction  
The continuous emergence of drug-resistant pathogens brings up the need to develop new antimicrobial products which can supply enhanced performance for the treatment of infections and asepsis [1]. Chronical wounds represent a burden to healthcare facilities and are a cause of morbidity among affected patients. Hosted microbes develop complex interactions between themselves and the environment, making healing assessment imprecise and precluding a definitive treatment protocol [2]. Precisely, the prevalence of pressure ulcers reaches around 38% of hospitalized individuals, and such wounds have been found harboring multidrug-resistant microorganisms. Among other factors, increasingly common out-of-hospital care can contribute to the propagation of these resistant strains [3]. With the advances in the field of nanoscience, nanoscale materials have been studied as potential antimicrobial agents due to their enhanced chemical and physical properties, including their greater surface area, which allows efficient interaction with microorganisms [4]. In this context, silver nanoparticles (AgNPs) remain as the most popular nano-material displaying documented activity against pathogens, appearing enrolled in other several biomedical applications [5]. AgNPs can be embedded in dressings, dental materials,medical devices and lotions for their functional usage in the clinical setting [4]. Due to the great relevance of AgNPs in the medical practice, a thorough investigation of their mechanism of action is still required, in order to infer their long-term efficiency and safety for practical purposes. In addition, knowledge concerning mechanisms of bacterial adaptation to nanoparticles remains limited, demanding a further examination of the potentially involved molecular processes [6]. The mechanism of action of silver nanoparticles against bacteria may involve the following phenomena: (i) nanoparticles adherence onto the surface of cell wall [7], leading to increased permeability and death [8]; (ii) formation of cell-wall inhibited due to the anchoring of silver to the cell membrane [8; 9]; (iii) modulation of cellular signals and the rise of oxidative stress, increasing cell porosity [8]; (iv) inactivation of thiol groups from enzymes and proteins [8; 10]; (v) prevention of DNA replication, cell division and respiratory chain processes due to reaction of AgNPs with DNA molecules [8; 10; 11]; and (vi) inhibition of cell growth by dephosphorylation of protein substrates in bacteria [12]. \"Green\" nanotechnology aims to implement sustainable synthesis protocols, which primarily involve reduced generation of waste and toxic derivatives, as well as the employment of renewable feedstock [13]. The use of environmentally safe methods for the preparation of functional nanomaterials is crucial for their practical application [14]. Microbe-assisted synthesis of nanoparticles fits to the concept of green chemistry, generating effective antimicrobial products which are possibly less toxic than those obtained through conventional chemical synthesis [15]. Besides that, nanoparticles can be combined to natural matrices to give rise to novel biocomposites, achieving a greater range of properties and applications [16]. Metabolomics encompass the systematic evaluation of a subset of metabolites produced by an organism, in order to be correlated with molecular mechanisms of interest [17]. In this case, metabolomics configures as a distinguished approach to study the impact of antimicrobial materials on biologic systems. Bacteria produce a large spectrum of volatile metabolites related to essential pathways and possess valuable biochemical meaning [18]. Such volatile organic compounds (VOCs) can be conveniently assessed through sampling of culture's headspace [19]. Acquired VOC profiles can reflect metabolic disturbances suffered by bacteria and be a useful tool to identify novel mechanisms involved in the antibacterial activity of AgNPs, also enabling us to observe how metabolic responses vary among species.