From Residues to Added-Value Bacterial Biopolymers as Nanomaterials for Biomedical Applications

Abstract

Bacterial biopolymers are naturally occurring materials comprising a wide range of molecules with diverse chemical structures that can be produced from renewable sources following the principles of the circular economy. Over the last decades, they have gained substantial interest in the biomedical field as drug nanocarriers, implantable material coatings, and tissue-regeneration scaffolds or membranes due to their inherent biocompatibility, biodegradability into nonhazardous disintegration products, and their mechanical properties, which are similar to those of human tissues. The present review focuses upon three technologically advanced bacterial biopolymers, namely, bacterial cellulose (BC), polyhydroxyalkanoates (PHA), and γ-polyglutamic acid (PGA), as models of different carbon-backbone structures (polysaccharides, polyesters, and polyamides) produced by bacteria that are suitable for biomedical applications in nanoscale systems. This selection models evidence of the wide versatility of microorganisms to generate biopolymers by diverse metabolic strategies. We highlight the suitability for applied sustainable bioprocesses for the production of BC, PHA, and PGA based on renewable carbon sources and the singularity of each process driven by bacterial machinery. The inherent properties of each polymer can be fine-tuned by means of chemical and biotechnological approaches, such as metabolic engineering and peptide functionalization, to further expand their structural diversity and their applicability as nanomaterials in biomedicine.

Comparative Analysis of Bacterial Cellulose Membranes Synthesized by Chosen Komagataeibacter Strains and Their Application Potential

“…Depending on the Komagataeibacter strain and the culture conditions used during cultivation, the obtained cellulose membranes differ in properties such as thickness; the content of dry cellulose and exopolysaccharides (EPS), which are hardly soluble in water; fiber density; pellicle flexibility; water-binding capacity; the degree of polymerization; and the crystallinity index [ 8 , 20 , 21 , 22 ]. Therefore, it is important to properly select the producing strain depending on the intended use in various fields of industry and medicine.…”

Advances in Polyhydroxyalkanoate Nanocarriers for Effective Drug Delivery: An Overview and Challenges

“…In the past decade, PHA-based nanoparticles as drug carriers have garnered significant attention for treating various diseases, owing to their potential to improve existing drug delivery systems via the design of novel dosage forms. Such formulations could have a better treatment outcome than conventional therapy due to their promising physicochemical properties as mentioned earlier [ 18 ], including (i) the ability to overcome the solubility of hydrophobic drugs, (ii) being readily manipulated for active targeting, (iii) the stabilization of chemotherapeutic agents, (iv) full biocompatibility and non-immunogenicity, and (v) superior pharmacokinetics and pharmacodynamics compared to free drug therapy [ 19 , 20 , 21 , 22 , 23 ]. However, US Food Drug Administration (FDA)-approved PHA-based nanomedicines for treatment are unavailable.…”

Bacterial Cellulose Properties Fulfilling Requirements for a Biomaterial of Choice in Reconstructive Surgery and Wound Healing

“…Considering the different types of drug administration to the patient's body (including dermal, transdermal and oral administration) and the different types of conditions managed with such treatments, a large number of published studies focus on an attempt to create an effective BCbased system, enabling the effective delivery of selected drugs to a wound or diseased tissue (Ciolacu et al, 2020). Such systems involve carriers based on whole fragments of membranes and its composites, cellulose beads formed in shake cultures, as well as cellulose fibers, which are used for creating hybrids for drug immobilization (Shi et al, 2014;Shao et al, 2016;Bayazidi et al, 2018;Cacicedo et al, 2018;Blanco et al, 2021). The latest trends in this area are oriented towards developing controlled systems targeting specific areas undergoing treatment and stimulating specific factors to reduce the adverse effects of the drug on healthy tissues.…”

“…), antibiotics (amoxicillin, ciprofloxacin, gentamicin, etc. ), or other chemical compounds (e.g., glycerol, glutaraldehyde, ε-poly-L-Lysine, nisin, ocetnidine, rutin) (Silva et al, 2014;Shao et al, 2016;Anton-Sales et al, 2019;Gorgieva and Trček, 2019;Jiji et al, 2020;Blanco et al, 2021;Emre Oz et al, 2021;Fonseca et al, 2021;Meamar et al, 2021). Larger molecules such as proteins (e.g., albumin, lysozyme, lipase or phospholipase) and growth factors should be adequately immobilized in the membrane after modifying the porosity of the cellulose nanostructure (Wu et al, 2017;Drozd et al, 2019;Wang et al, 2020).…”