title: Bioactive DOPA melanin isolated and characterised from a marine actinobacterium Streptomyces sp. MVCS6 from Versova coast.
abstract: The melanin pigment produced from Streptomyces sp., MVCS6 was isolated and dihydroxyphenyalanine (DOPA) melanin compound was biochemically identified and spectroscopically characterised (ultraviolet and FT-IR). DOPA melanin showed a promising activity as an antibacterial natural product against 12 pathogenic bacteria from hospital isolations, particularly, against Pseudomonas aeruginosa RMMH7 (inhibition zone of 18 ± 0.02 at 30 μg/disc, and MIC of 10 ± 0.02 μg/mL) and Vibrio parahaemolytics RMMH12 (inhibition zone of 15 mm ± 0.03 at 30 μg/disc, and MIC of 14 ± 0.02 μg/mL). Moreover, in vitro evaluation of reducing power (Ascorbic Acid Equivalent (160 μg/mL)), DPPH radical-scavenging (89%), NO-scavenging (72%) and lipid peroxidation activities (89.6%) were determined. Cytotoxicity of DOPA melanin against cervical cancer cell line showed a dose-response activity, and IC50 value was found to be 300 μg/mL. These results would open the way to propose Streptomyces sp. MVCS6 as a promising source of bioactive eumelanin with therapeutic potential in medicine.
authors.affiliation: a Central Institute of Fisheries Education, ICAR-Deemed University , Off Yari Road, Versova, Andheri (W), Mumbai 400 061 , Maharashtra , India.|b Department of Marine Science , Bharathidasan University , Tiruchirappalli 620 024 , Tamil Nadu , India.
authors.forename: P
authors.initials: P
authors.lastname: Sivaperumal
authors.affiliation: a Central Institute of Fisheries Education, ICAR-Deemed University , Off Yari Road, Versova, Andheri (W), Mumbai 400 061 , Maharashtra , India.
authors.forename: K
authors.initials: K
authors.lastname: Kamala
authors.affiliation: b Department of Marine Science , Bharathidasan University , Tiruchirappalli 620 024 , Tamil Nadu , India.
authors.forename: R
authors.initials: R
authors.lastname: Rajaram
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000302:isolation & purification; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification; D045744:Cell Line, Tumor / Q000187:drug effects; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification; D006801:Humans; D007194:India; D008826:Microbial Sensitivity Tests; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012623:Seawater / Q000382:microbiology; D013302:Streptomyces / Q000737:chemistry*; D014736:Vibrio parahaemolyticus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D000975:Antioxidants; D004295:Dihydroxyphenylalanine; C040616:DOPA melanin
keywords: FT-IR; antibacterial; antioxidant; cytotoxicity activity; melanin