Antibacterial activities of marine epibiotic bacteria isolated from brown algae of Japan

Abstract

One hundred and sixteen epibiotic bacteria were isolated from the surface of nine species of brown algae Sargassum serratifolium, S. fusiforme, S. filicinum, Padina arborescens, Undaria pinnatifida, Petalonia fascia, Colpomenia sinuosa, Scytosiphon lomentaria and Ecklonia cava which were collected at Awaji Island, Japan. Primary screening results using disc-diffusion assay revealed that, among the bacteria isolated 20% of epibiotic bacteria exhibited antibacterial activity. Among them, 10 bacteria which showed high antibacterial activity were further studied for their ability against (i) a set of fouling bacteria isolated from marine natural biofilm, (ii) some luminescent Vibrio and Photobacterium species and (iii) a panel of pathogenic bacteria. In general, inhibitory activities were high or moderate against fouling bacteria, Vibrio and Photobacterium species, while they were found to be low against pathogenic bacteria tested. The phylogenetic analysis using 16S rRNA sequencing revealed that all of the bacteria with high antibacterial activity showed a close affiliation with genus Bacillus. This result suggested that the genus Bacillus are efficient producers of antibacterial compounds and these epibiotic bacteria isolated are highly successful colonizers on macroalgal surfaces.

Jania rubens-associated bacteria: molecular identification and antimicrobial activity

“…Burgess et al (2003) isolated several bacteria with high antifouling activity and found that most of these bacteria belonged to Bacillus, such as B. pumilus, B. licheniformis and B. subtilus. Kanagasabhapathy et al (2006) have isolated B. pumilus and other Bacillus species from different brown alga. Kanagasabhapathy et al (2008) investigated antimicrobial activity of epiphytic bacteria from several red algae and found that the highest activity was produced by certain Bacillus species especially B. cereus and B. pumilus.…”

Selective Extraction of Bacterial DNA from the Surfaces of Macroalgae

“…Marine living surfaces are often inhabited by diverse and complex communities of bacteria (2,13,14,17,18,35,36) and hence harbor biodiversity, ecological processes, and biotechnological potential distinct from those of surrounding planktonic communities (7, 19-21, 24, 39, 41). Bacterial epiphytic communities on algae have been studied in terms of nutrient acquisition (5,10), carbon exchange (4), resistance to biofouling (6,37), the production of bioactive compounds (1,14), and, perhaps most notably, the lack of the host's normal morphological development in the absence of a bacterial community (23,25,30,32).…”

“…Bacterial epiphytic communities on algae have been studied in terms of nutrient acquisition (5,10), carbon exchange (4), resistance to biofouling (6,37), the production of bioactive compounds (1,14), and, perhaps most notably, the lack of the host's normal morphological development in the absence of a bacterial community (23,25,30,32).…”

Identification of epiphytic bacterial communities associated with the brown alga Splachnidium rugosum

“…Surfaces of marine organisms have been documented to host a higher percentage of antimicrobial compound producing bacteria when compared to surrounding marine environments (Zheng et al 2005). Up to 20 % of bacteria isolated from brown seaweeds have been reported to exhibit antibacterial activity (Kanagasabhapathy et al 2006). Three isolates (MA_6, NA_1 and NSA_10) were active against the Gram-negative indicator P. putida (ATCC27853) ( Table 3).…”