GC-MS Profiling and In Silico Pathway Mapping of Brevibacterium casei VRK 1 Metabolites for exploring Anti-inflammatory and Antioxidant Activities.

The emergence of new metabolites from marine actinobacteria for disease treatment has increased significantly. In this context, the study focused on isolating and characterizing a marine actinobacterium from Ervadi Beach in the Ramanathapuram district. The isolated strain was identified by proteomic fingerprinting and 16S rRNA gene analysis. The ethyl acetate crude extract of Brevibacterium casei VRK 1 was tested for its antioxidant and anti-inflammatory properties. GC-MS analysis was used to identify the bioactive metabolites. The classification of bioactive metabolites, their functions, and their metabolic pathways was screened using an in silico approach. Based on the proteomic fingerprinting and sequencing results, the strain was identified as Brevibacterium casei VRK1. Notable anti-inflammatory activity was observed at 500 µg/mL, with an inhibition percentage of 35.76%. Strong antioxidant activity was also detected for DPPH and ABTS at 500 µg/mL, with inhibition percentages of 45.9% and 40.12%, respectively. GC-MS analysis confirmed the presence of ten novel bioactive metabolites with the highest probability values. The bioactive metabolites of B. casei VRK were identified as organometalloid compounds, fatty acyls, steroids, carboxylic acids, and their derivatives. The metabolomics results highlighted the biological functions of B. casei VRK1, including antidepressant, carboxylesterase, and dihydrofolate reductase inhibition. Pathway analysis results revealed that metabolites were associated with the biosynthesis of steroid hormones and fatty acids. This provides valuable insights into in silico methods for identifying the importance of secondary metabolites with anti-inflammatory and antioxidant effects. The KEGG pathway analysis results offer initial evidence of secondary metabolites and their related pathways.