Nayband Bay Research Articles

Isolation, Identification and Optimization of Phenanthrene Degrading Bacteria From the Coastal Sediments of Nayband Bay

Background: Biodegradation of polycyclic aromatic hydrocarbons (PAHs) contaminated sediments is an effective remediation technique and its success depends on the optimal condition of PAH-degrading isolates. Objectives: The present study was conducted to isolate the PAHs-degrading bacteria from Nayband bay mangrove sediments and to investigate the effect of different variables on phenanthrene (Phe) biodegrading efficiency of the most effective isolated strains, by using response surface methodology (RSM). Materials and Methods: Phe degrading bacteria were isolated from surface sediments. Isolated strains were then identified by biochemical and molecular (16S rDNA gene sequence) analysis. RSM was employed to evaluate the optimum biodegradation of Phe by the most effective isolated strain. The investigated parameters included the temperature, inoculum sizes, pH, NH4Cl concentration, and salinity. Results: One Gram-negative bacterium strain (SBU1) was isolated from enrichment consortium SBU. SBU1 have been identified by 16S rDNA sequence analysis and revealed 96% homology with Roseovarius sp., the biodegradation activity of the SBU1 was properly interpreted using a second-order polynomial regression model. Maximum biodegradation efficiency was predicted at pH = 8.2, temperature≈35˚C, salinity = 30 ppt, NH4Cl concentration = 0.13 g/L and inoculum size = 0.2 OD600nm. Under these conditions the aerobic biodegradation rate reached up to 28.4%. Conclusions: Indigenous bacteria from mangrove surface sediments of Nayband bay were found to be able to degrade Phe. The similarity of the predicted and observed results confirmed the validity and applicability of RSM in optimization processes.

SPATIAL DISTRIBUTION AND ASSEMBLAGE STRUCTURE OF FORAMINIFERA IN NAYBAND BAY AND HALEH ESTUARY, NORTH-WEST OF THE PERSIAN GULF

The spatial distribution of benthic foraminiferal assemblage of Nayband Bay and Haleh Estuary in the North-West of the Persian Gulf, was explored during 2011-2012 . The relationship between spatial pattern of foraminifera assemblages and the ambient factors (i.e. water temperature, salinity, pH, dissolved oxygen, sediment grain size distribution, sediment organic content, and CaCO3 concentration of sediments) was measured. The most abundant benthic foraminifera species which were found in the studied area include Ammonia beccarii, Eponides repandus, Quinqueloculina sp., Elphidium sp. The two most abundant species belongs to Rotaliidae family. The specimen groups presented in the study area were somehow the same, and their relative abundance did not vary tremendously in sites consisting of foraminifera assemblages. The fauna shows affinities to those of the southern coastline of the Persian Gulf and also the Oman Sea. The BIO-ENV analysis identified temperature, salinity, pH, and total organic matter as the major environmental variables influencing the infaunal pattern. Generally foraminiferal populations were sparse in the study area, which may be due to the low depth and consequently, low distribution of foraminiferal specimens.

Antimicrobial activity of marine sponge extracts of offshore zone from Nay Band Bay, Iran

Summary In vitro antimicrobial activity of six sponge species (Porifera), collected from offshore zone of Nay Band Bay, Bushehr, (Iranian coast of Persian Gulf), against certified strains of bacteria (two Gram-positive: Bacillus subtilis ATTC 6633, Staphylococcus aureus ATCC 25923 and two Gram-negative: Pseudomonas aeroginosa ATCC 27853, Escherichia coli ATCC 25922) and fungi ( Candida albicans ATCC 10231, Aspergillus spp. PTCC 5266, Penicillium spp. PTCC 5251) were conducted in this study. Three extracts of each sponge with solvents of different polarity were evaluated (methanol, ethyl acetate, and n -hexane) through the disk diffusion assay. The results showed that 83.3% (15 from 18 extracts) of the sponge extracts presented activity against at least one bacterial strain and 83.3% were active against at least one fungus. On the basis of this study, the activity against bacteria and fungi was moderate. Also, minimum inhibitory concentrations (MICs) of the extracts with desirable activities (inhibition zone more than 9 mm) in the previous stage were assessed. Among the 18 extracts, 83.3% showed activity against some of the four bacteria. The three most active sponges against four tested bacteria were: Gelliodes spp., Spheciospongia spp.1, Spheciospongia spp.2. Among the 18 extracts, 66.6% showed activity against Candida albicans and the most active sponge against yeast was Spheciospongia inconstans . This is the first report of biological activities of marine sponges from Iranian coast of Persian Gulf.