Bioprospecting of Microorganism-Based Industrial Molecules. Группа авторов

proliferation, antioxidative effect, and antimicrobial activity against E. coli and S. aureus. In vivo studies on Wistar rats showed enhanced wound healing compared with only hyaluronic acid and pullulan polymer [42]. Gellan gum infused with a bioactive glass (BAG) used to encapsulate human adipose stem cells for osteogenic differentiation, displayed increased cell viability, improved mechanical properties, and strong bone mineralization [48]. A chitosan and xanthan gum‐based hydrogel was used for drug delivery of the antiviral drug acyclovir. Parameters such as swelling dynamics and entrapment efficiency were studied, and the results concluded the potential for such hydrogel for the efficient antiviral drug delivery [49].

      3.6.3 Applications in Nanotechnology

      In recent years, microbial gums owing to their unique functional properties have been employed in nanotechnology, which has subsequent applications in food and pharmaceutical industries. Various nanostructure has been developed using microbial gums such as nanoparticles, nanofibers, nanocomplexes, and nanoemulsions [50].

      A gellan gum containing silver nanoparticle‐based hydrogen sulfide (H₂S) biosensor for the detection of meat spoilage was developed. Using this system, H₂S was detected in chicken breast, and silver carp; sensor present in the packaging of meats changes color from yellow to white in the presence of H₂S. This is a cost‐effective, non‐destructive, and robust method for the detection of meat spoilage [51]. Xanthan gum‐shellac nanoparticles loaded with cinnamon bark extract were assembled by anti‐solvent precipitation method. The nanoencapsulation of the bioactive extract resulted in improved thermal stability and pH resistance having antioxidative properties of the extract [52]. The insulin delivery system triggered by pH was developed using acryloyl cross‐linked dextran dialdehyde (ACDD) nanoparticles to immobilize glucose oxidase. This system works under gastric conditions (pH 1.2), as well as intestinal conditions (pH 7.4) and proved to be a reliable vector for drug delivery [53]. Nanoemulsions made using microbial gums xanthan and welan in combination with Rosemary essential oil were developed. The nanostructure constructed was less than 150 nm in diameter and showed the best physical stability at 0.4% gum concentration with welan gum containing nanoemulsions showing better properties [43].

3.7 Conclusions and Perspectives

Microbial gums play a key role in many industries and have seen a steady rise in demand over the years. Some gums such as xanthan and gellan are used more often than others due to their unique functional properties. In recent times, there has been an increase in research on microbial gums, especially on increasing their production, understanding their properties and function, creating novel composites of gums with unique properties, and exploring different microbiomes for novel gums. Advancements in molecular biology, structural biology, bioprocess engineering, and metabolic engineering will help in the future research of microbial gums. The focus of obtaining microbial gums through an economical and sustainable manner by the use of cheap substrates or increasing the productivity of a strain by molecular biology would be crucial areas that future research could make great strides.

Acknowledgments

      RB acknowledges the research associate fellowship provided by the Council of Scientific and Industrial Research (CSIR). The authors acknowledge the contributions ofDr. SVN Vijayendra, Dept. Microbiology and Fermentation Technology for critical comments and suggestions. Authors acknowledge the kind approval of the Director, CSIR‐CFTRI Mysuru, for this work. This manuscript has been approved by planning, monitoring, and coordination (PMC) section, CFTRI‐CSIR vide approval number PMC/2020‐21/122.

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