Antibacterial Activity of Marine Bacterial Pigments Obtained from Arabian Sea Water Samples

Abstract

The Arabian Sea environment harbors numerous microorganisms that have developed unique metabolic abilities to ensure their survival in hostile habitats. The bacterial pigments are considered to be important metabolic product which is useful for bacteria and may exert specific biological properties including antibacterial activity. Moreover, there is an imperative need for exploring new antibacterial agents since; there are drug resistance issues with the existing antibiotics. Therefore, the present study was aimed to assess antibacterial activity of pigments extracted from marine bacteria of Arabian Sea water samples and to characterize the potent antibacterial pigment producing isolate. The water samples were obtained from Tithal (Valsad), Diu, Daman and Dandi beaches of India. Total 9 distinct pigmented bacteria were isolated. The pigments extracted from bacterial isolates were assessed for the antibacterial, antioxidant and anticancer activities. Four pigment producing isolates (NP5, NP6, NP8 & NP9) among the nine isolates showed good antibacterial activity against the different bacterial cultures. Among these four isolates, NP9 showed maximum antibacterial activity against all the test cultures. The pigment obtained from NP5 isolate exhibited higher antioxidant property as compared to NP6, NP8 and NP9. However, none of the pigments obtained from NP5, NP6 and NP9 exhibited anti-cancerous activity on MCF-7 cell line. The molecular identification by16srDNA sequencing revealed that NP9 belongs to Candidatus chryseobacterium massiliae (MK213063). Chryseobacterium has been known to produce yellow pigment; however, for the first time, the study suggests that Candidatus chryseobacterium massiliae strain produces red pigment with potent antibacterial activity. However, its antibacterial activity must be tested with more number of pathogens and study in disease animal model is needed to confirm the results of the study.

Keywords

• arabian sea
• bacteria pigments
• antibacterial
• antioxidant and anticancer activities