Microbial resistance and deprivation of the effective drugs have become the foremost problem that propels to seek out for advanced approach. This concept initiated a need to search for more effective antimicrobial compounds from reliable sources. The Streptomyces is grouped under phylum Actinobacteria and are considered prolific producers of antibiotics, around 70% of presently available antibiotics are contributed by Streptomyces alone. In this study, Mangroves of the Mangalore Coast offered a unique source for screening Actinomyces group of microorganisms. We investigated on the four soil samples collected from Mangrove swamps of Mangalore, Karnataka, India. Based on their culture traits, the 18 distinct Actinomyces isolates were analyzed through a series of morphological and biochemical tests on starch casein nitrate (SCN) media.Culture biomasses were subjected for intracellular protein extraction through acetone precipitation method; the extracted proteins from each Actinomyces isolate were examined for antimicrobial activity against test organisms. The isolate ANTB-YKMU4 showed potential antimicrobial activity against significant number of test organisms; Bacillus cereus, Proteus vulgaris, Staphylococcus aureus, Salmonella typhimurium, and Pseudomonas aeruginosa. The isolate ANTB-YKMU4 through 16 s rRNA gene sequence analysis was identified as Streptomyces tauricus strain with GenBank accession no. MW785875.1. The S. tauricus further cultivated for efficient biomass growth on SCN media for subsequent protein extraction and purification by a series of Electrophoretic and chromatographic techniques. Thus, by intracellular extractions from S. tauricus resulted in the identification of peptide with a molecular weight of 266 Da that was characterized by LC-MS.

The Glutamicibacter group of microbes is known for antibiotic and enzyme production. Antibiotics and enzymes produced by them are important in the control, protection, and treatment of chronic human diseases. In this study, the Glutamicibacter mysorens (G. mysorens) strain MW647910.1 was isolated from mangrove soil in the Mangalore region of India. After optimization of growth conditions for G. mysorens on starch casein agar media, the micromorphology of G. mysorens was found to be spirally coiled spore chain, each spore visualized as an elongated cylindrical hairy appearance with curved edges visualized through Field Emission Scanning Electron Microscopy (FESEM) analysis. The culture phenotype with filamentous mycelia, brown pigmentation, and ash–colored spore production was observed. The intracellular extract of G. mysorens characterized through GCMS analysis detected bioactive compounds reported for pharmacological applications. The majority of bioactive compounds identified in intracellular extract when compared to the NIST library revealed molecular weight ranging below 1kgmole−1. The Sephadex G-10 could result in 10.66 fold purification and eluted peak protein fraction showed significant anticancer activity on the prostate cancer cell line. Liquid Chromatography–Mass Spectrometry (LC–MS) analysis revealed Kinetin-9-ribose and Embinin with a molecular weight below 1 kDa. This study showed small molecular weight bioactive compounds produced from microbial origin possess dual roles, acting as antimicrobial peptides (AMPs) and anticancer peptides (ACPs). Hence, the bioactive compounds produced from microbial origin are a promising source of future therapeutics.

Endophytes contribute to the synthesis of significant metabolites in symbiotic association with their host plants. On considering the medicinal importance of the prominent tree species Pajanelia longifolia (Willd.) K. Schuman, the study was conducted to isolate and identify the endophytic bacteria and fungi for their bioactivity. The isolation of endophytic bacteria and fungi were performed by surface sterilisation of the stem and leaf samples of P. longifolia. The obtained bacterial and fungal endophytic isolates were maintained in nutrient agar and Potato Dextrose Agar (PDA) media and were examined for colony morphology and microscopic appearances with varied biochemical characterisations. Furthermore, both the fungal and bacterial isolates were subjected to solvent extractions to evaluate antibacterial activity. Also, anti-proliferative effects due to apoptotic induction by the endophytic fungal extracts were checked against proliferative yeast cells. Moreover, endophytic bacteria belonging to Enterococcaceae had shown antibacterial activity against Salmonella species. In the present study, fungal species belonging to Cladosporium predominantly found to inhabit as endophytic fungi in the plant samples. Also, this particular fungus among other selected endophytic fungi attributed to causing effective anti-proliferative activity. The endophytic bacteria belonging to Enterococcus and Micrococcus genera showed significant antimicrobial activity against Salmonella typhimurium (ATCC 23564).

A non-fluorescent pigment produced from the fluorescent Bacillus endophyticus AVP-9 which possess abundant lutein content considered as a xanthophyl-type compound with potentially beneficial pharmacological properties for enhancing human health. In this context, bacterial lutein was extracted by employing different solvents to isolate from Bacillus endophyticus was examined in this study. Chromatographically purified lutein was spectrally characterized using ultraviolet-visible spectrometry and spectral analysis was carried through liquid chromatography-mass spectrometry, functional group identification was done by using fourier transform-infrared spectroscopy, structural determination by nuclear magnetic resonance spectrometry. By using hexane and ethyl acetate (7:3) with the flow rate of 5ml/min, was proven to be an excellent solvent phase for separation of lutein, meaning that up to 90% pure lutein generated with a 60% estimated yield. The purified compound identified as a β, ε-3, 31-diol (lutein) having molecular weight of 568.6g/mol with the molecular formula C40H56O2 which exhibits potential antibacterial activity against E. coli (35mm) followed by S. typhi (33mm), S. flexneri (30mm), P. aureginosa (29mm), M. lutea (28mm), P. vulgaris (24mm), S. aureus (21mm) and lowest antibacterial activity against V. cholera (19mm). Purified pigment shows concentration dependent antioxidant activities with IC50 values of pigment was found to be 4.5 mg/ml. Whereas anti-proliferation activity pigment shows considerable effect MCF-7 and LNCaP cell lines, when treated with 100µg/ml, cell viability was decreased to 36.363% at IC50 value of 21.935 µg/ml and for LNCaP, the cell viability was decreased to 42.449% at IC50 value of 56.937 µg/ml.