Gelatin-Graphene Oxide Nanocomposite Hydrogels for Kluyveromyces lactis Encapsulation: Potential Applications in Probiotics and Bioreactor Packings

Abstract

Nutraceutical formulations based on probiotic microorganisms have gained significant attention over the past decade due to their beneficial properties on human health. Yeasts offer some advantages over other probiotic organisms, such as immunomodulatory properties, anticancer effects and effective suppression of pathogens. However, one of the main challenges for their oral administration is ensuring that cell viability remains high enough for a sustained therapeutic effect while avoiding possible substrate inhibition issues as they transit through the gastrointestinal (GI) tract. Here, we propose addressing these issues using a probiotic yeast encapsulation strategy, Kluyveromyces lactis, based on gelatin hydrogels doubly cross-linked with graphene oxide (GO) and glutaraldehyde to form highly resistant nanocomposite encapsulates. GO was selected here as a reinforcement agent due to its unique properties, including superior solubility and dispersibility in water and other solvents, high biocompatibility, antimicrobial activity, and response to electrical fields in its reduced form. Finally, GO has been reported to enhance the mechanical properties of several materials, including natural and synthetic polymers and ceramics. The synthesized GO-gelatin nanocomposite hydrogels were characterized in morphological, swelling, mechanical, thermal, and rheological properties and their ability to maintain probiotic cell viability. The obtained nanocomposites exhibited larger pore sizes for successful cell entrapment and proliferation, tunable degradation rates, pH-dependent swelling ratio, and higher mechanical stability and integrity in simulated GI media and during bioreactor operation. These results encourage us to consider the application of the obtained nanocomposites to not only formulate high-performance nutraceuticals but to extend it to tissue engineering, bioadhesives, smart coatings, controlled release systems, and bioproduction of highly added value metabolites.

Preparation and Characterization of an Injectable and Photo-Responsive Chitosan Methacrylate/Graphene Oxide Hydrogel: Potential Applications in Bone Tissue Adhesion and Repair

“…Hydrogels were molded into 20 mm diameter and 25 mm height cylinder-shaped constructs. This test measured compression force at a 1.0 mm/s speed and 15 mm penetration length using a 10 mm cylindrical probe [ 49 ].…”

“…GO is biocompatible, biodegradable, antibacterial, physiologically stable, and sensitive to temperature and pH changes to elicit drug release, but several reports have also discussed its promising potential as reinforcement to enhance mechanical response and colloidal stability, mimic tissue microenvironments, and promote bone regeneration [ 45 , 46 , 47 , 48 ]. Moreover, the abundance of oxygen-rich functional groups on its surface makes it suitable for relatively simple chemical functionalization schemes and protein adsorption [ 42 , 43 , 44 , 49 , 50 ]. Nevertheless, recent reports have also shown that GO can bioaccumulate and induce inflammatory and cytotoxic responses, and thus only low doses are recommended for biological applications.…”

Advancements in the Pharmaceutical Applications of Probiotics: Dosage Forms and Formulation Technology

“… 160 Patarroyo et al developed gelatin-graphene oxide nanocomposite hydrogels with larger pore sizes favorable for the entrapment and proliferation of Kluyveromyces lactis . 161 Nanocomposite hydrogels also exhibited pH-dependent swelling ratio, tunable degradation rates, and high mechanical stability and integrity in simulated gastrointestinal fluids and during bioprocessing. 161 Zhang et al fabricated sodium alginate/cellulose nanofiber gel macrospheres (ACMs) by extruding a mixture of sodium alginate and 2,2,6,6,-tetramethyl-1-piperidinyloxy radical (TEMPO)-oxidized cellulose nanofiber into CaCl 2 solutions for cross-linking, where L. plantarum was incorporated as the probiotic bacteria.…”

“… 161 Nanocomposite hydrogels also exhibited pH-dependent swelling ratio, tunable degradation rates, and high mechanical stability and integrity in simulated gastrointestinal fluids and during bioprocessing. 161 Zhang et al fabricated sodium alginate/cellulose nanofiber gel macrospheres (ACMs) by extruding a mixture of sodium alginate and 2,2,6,6,-tetramethyl-1-piperidinyloxy radical (TEMPO)-oxidized cellulose nanofiber into CaCl 2 solutions for cross-linking, where L. plantarum was incorporated as the probiotic bacteria. 162 Since ACMs shrank in the simulated gastric fluids, the penetration of gastric acid into the ACMs was low, thereby protecting the encapsulated probiotics from the acidic environment.…”

Impact of Graphene Derivatives as Artificial Extracellular Matrices on Mesenchymal Stem Cells

“…The fabricated nanocomposites had larger pore sizes, allowing for cell entrapment and proliferation, a pH-dependent swelling ratio, controllable degradation rates, and enhanced mechanical stability and integrity. As a result, these nanocomposites hold great promise for the formulation of high-performance nutraceuticals, as well as tissue engineering and high-value metabolite production [147]. Similarly, Jiao et al developed a biodegradable rGO gelatine (rGO@Ge) composite to investigate its impact on rat adipose-derived MSCs [148].…”