Improved Exopolymer Production by Chromohalobacter canadensis Cultures for Its Potential Cosmeceutical Applications

Exploring Extremophiles from Bulgaria: Biodiversity, Biopolymer Synthesis, Functional Properties, Applications

Bulgaria stands out as a country rich in diverse extreme environments, boasting a remarkable abundance of mineral hot waters, which positions it as the second-largest source of such natural resources in Europe. Notably, several thermal and coastal solar salterns within its territory serve as thriving habitats for thermophilic and halophilic microorganisms, which offer promising bioactive compounds, including exopolysaccharides (EPSs). Multiple thermophilic EPS producers were isolated, along with a selection from several saltern environments, revealing an impressive taxonomic and bacterial diversity. Four isolates from three different thermophilic species, Geobacillus tepidamans V264, Aeribacillus pallidus 418, Brevibacillus thermoruber 423, and Brevibacillus thermoruber 438, along with the halophilic strain Chromohalobacter canadensis 28, emerged as promising candidates for further exploration. Optimization of cultivation media and conditions was conducted for each EPS producer. Additionally, investigations into the influence of aeration and stirring in laboratory bioreactors provided valuable insights into growth dynamics and polymer synthesis. The synthesized biopolymers showed excellent emulsifying properties, emulsion stability, and synergistic interaction with other hydrocolloids. Demonstrated biological activities and functional properties pave the way for potential future applications in diverse fields, with particular emphasis on cosmetics and medicine. The remarkable versatility and efficacy of biopolymers offer opportunities for innovation and development in different industrial sectors.

Exploring the potential of Halomonas levan and its derivatives as active ingredients in cosmeceutical and skin regenerating formulations

Demand on natural products that contain biological ingredients mimicking growth factors and cytokines made natural polysaccharides popular in pharmaceutical and cosmetic industries. Levan is the β-(2-6) linked, nontoxic, biocompatible, water-soluble, film former fructan polymer that has diverse applications in pharmacy and cosmeceutical industries with its moisturizing, whitening, anti-irritant, anti-aging and slimming activities. Driven by the limited reports on few structurally similar levan polymers, this study presents the first systematic investigation on the effects of structurally different extremophilic Halomonas levan polysaccharides on human skin epidermis cells. In-vitro experiments with microbially produced linear Halomonas levan (HL), its hydrolyzed, (hHL) and sulfonated (ShHL) derivatives as well as enzymatically produced branched levan (EL) revealed increased keratinocyte and fibroblast proliferation (113-118 %), improved skin barrier function through induced expressions of involucrin (2.0 and 6.43 fold changes for HL and EL) and filaggrin (1.74 and 3.89 fold changes for hHL and ShHL) genes and increased type I collagen (2.63 for ShHL) and hyaluronan synthase 3 (1.41 for HL) gene expressions together with fast wound healing ability within 24 h (100 %, HL) on 2D wound models clearly showed that HL and its derivatives have high potential to be used as natural active ingredients in cosmeceutical and skin regenerating formulations.

Genome Analysis of Halomonas elongata Strain 153B and Insights Into Polyhydroxyalkanoate Synthesis and Adaptive Mechanisms to High Saline Environments

Species of the Halomonas genus are gram-negative, aerobic, moderately halophilic bacteria that synthesize polyhydroxyalkanoates (PHAs) and other high-value products that have a wide range of potential uses in the food, feed, cosmetics, pharmaceutical, and chemical sectors. Genome sequencing studies allow for the description and comparison of genetic traits with other strains and species, allowing for the exploration of the organism's potential, necessary to further biotechnology applications. Here, the genome of Halomonas elongata strain 153B was sequenced, its features compared to 5 other strains and 7 species, and a description of features for adaptations to hypersaline environments and bioproducts synthesis was done. Whole-genome analysis showed H. elongata 153B has more similar features to the reference strain H. elongata DSM 2581 compared to 4 other reported strains. Comparative genomics showed 2064 core genomic clusters between the strains and 666 singletons for strain 153B. Several genes in transport and signaling, osmoregulation, and oxidative stress that have roles in adaptation to environments with high osmolarity were also revealed. These appear to form an intricate network of overlapping systems carefully coordinated to bring about adaptation. H. elongata 153B genes for the synthesis of PHAs, ectoine, vitamins, and the degradation of drugs and aromatic compounds were described. The results will aid in the study of halophile physiology, provide a mine for valuable enzymes, and help speed up research for other biotechnology applications.