Bio Prospecting of Marine‑derived Streptomyces spectabilis VITJS10 and Exploring its Cytotoxicity Against Human Liver Cancer Cell Lines

Background: Recently, numerous pathogens have developed resistance due to the indiscriminate use of commercial therapeutic drugs. Objective: The main aim of the study was to evaluate the bioactive potential of the Streptomyces spectabilis VITJS10 crude extract. Materials and Methods: The S. spectabilis VITJS10 ethyl acetate extract was tested for antibacterial, antioxidant, and cytotoxic properties. Genotypic characterization was done using 16S r‑DNA partial gene amplification and sequencing. The authenticity of the crude chemical constitutes were determined by gas chromatography–mass spectrometry (GC‑MS). Results: The antibacterial potential revealed the effective activity against Shigellaflexneri (MTCC No: 1457) (22 mm), Salmonella typhi (MTCC No: 1167) (23 mm), Escherichia coli (MTCC No: 1588) (22 mm), Pseudomonas aeruginosa (MTCC No: 4676) (22 mm) at 20 mg/mL concentration. Scavenging ability of the extract was determined using 2,2‑diphenyl‑1‑picrylhydrazyl (DPPH) assay revealing its 95% inhibition at 5 mg/mL concentration. Hepatocellular cancer cells (HepG2) cell line was used to evaluate the cytotoxicity by 3‑(4, 5‑dimethyl thiazol‑2yl)‑2, 5‑diphenyl tetrazolium bromide assay. The extract showed maximum inhibition at IC50of 250 μg/mL with 53.6% cell viability. The highest 16S rRNA gene sequence homogeneity was observed 99% similar with the novel strain S. spectabilis S3‑1. The chemical components of the crude extract of VITJS10 were detected with 37 chemical constituents. However three major compounds were identified, namely Sulfurous acid, 2‑ethylhexyl tridecyl ester, Phenol, 2,4‑bis (1,1‑dimethylethyl), and Trans‑2‑methyl‑4‑n‑pentylthiane, S, S‑Dioxide. Conclusion: Hence the present study justifies the overwhelming circumstantial evidence as the most bioactive metabolites from the marine origin, which has potential utilization in pharmaceutical industry.