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Due to exist of the different kinds of sea cucumbers and their biological activities, In this study, the antibacterial activities and the soap forming ability of powder, methanolic and saponins extracts of sea cucumber (Holothuria leucospilota). obtained from Lavan Island, were evaluated. Initially Sea cucumbers were dried and subsequently ground. Extraction was performed by methanol solvents to obtain total extract and 70% ethanol. The method of soaking was used in order to prepare the extract containing the ultimate amount of saponin compounds. With the aim of determine the quality of saponin, its index of foam forming ability was evaluated. The production of soap from marine cucumbers was carried out using the method of soaping fats and glycerin. Finally, sea cucumber soaps was produced using powder, methanolic and saponins extracts with ratios of 1, 5 and 10%. In order to fulfill of bacterial analysis, the effect of extracts and prepared soaps on Staphylococcus aureus was evaluated using tubular dilution method. The results of the experiment show that the minimum inhibitory concentration (MIC) of the methanolic extract and marine cucumber soap for Staphylococcus aureus is 10 and 5 mg / ml respectively. This index for saponin and its soap is 2 and 5 mg / ml. Regardless of the duration of the experiment, one-way analysis of variance test showed that there was a significant difference in the mean height between volumes of 10 ml and volumes of one, two, three, four and five ml (p <0.05). In other cases, no significant difference was observed in the mean floor height. The produced foam of the sea cucumber saponin remained for more than 12 hours, indicating a very high foam formin ability. In this project, the antibacterial and consequently anti-pimple of extracts and soaps produced from the Holothuria leucospilota obtained from Lavan Island were studied and confirmed. Therefore, this compounds can be used as an appropriate choice for the production of anti-pimple soaps. [ABSTRACT FROM AUTHOR]

Investigation on pearl oyster, Pinctada radiata growth and mortality parameters was carried out from September 2001 to October 2002 in west of Lavan Island using scuba diving method. Hinge length (H-LL) and Dorso-ventral measurement (D.Y.M) relationship was significantly (r2= 0.98) linear. Weight and dorso-ventral measurement relationship was shown to be W=0.0004 L 2.812(r2= 0.98). Asymptotic length (Loo) and growth rate (K) were estimated at 98 (mm) and 0.96 it respectively. More than 70 percent of the individuals were matured in April 2001. Mortality parameters including natural mortality (M), total mortality (Z) and fishery mortality (F) were estimated to be 1.21y-1, 1.68y-1 and 0.66y-1 respectively. Exploitation rate was estimated to be 0.27 in this survey.

Background and aims Overexposure to industrial noise pollution induce hearing loss workers. Occupational hearing loss may cause interference whit oral communication, so it may increase the risk of occupational accidents in workplace as well as affects whit social activities. This study was conducted on Lavan Island, are of oil extracting regions in the south of Iran. The object of this study was to evaluate noise pollution and determining the effect of noise enclosure on noise abatement. Methods The noise sources were recognized and noise pressure level was measured by CEL- 440. Noise dose of the exposed workers in high level noise area were measured by CEL 272. Results Major noise sources were gas turbines, diesel generators, compressors, fans and gas containing pips, noise contour map revealers that noise level were higher than the recommended national exposure limit. The results of workers noise dose show that their noise exposure were higher than the recommended value, (p

Samples for monthly variation of phytoplankton species were collected in two stations from October 1996 till September 1997. In this study 65 species of phytoplankton related to diatoms, dinoflagellates and blue-green algae were identified. Diatoms represent 44 species (67%) related to 25 genera, followed by 18 species (26%) related to 7 genera dinoflagellates and only 3 genus (7%) belong to the blue-green algae. The diversity of diatoms species mainly composed of Rhizosolenia (12 species) and (6 species) were markedly greater than the diversity of dinoflagellates which were composed Ceratium (11 species). The diversity of both groups were significantly greater than the blue-green algae. Diatoms and dinoflagellates were abundant during periods of low salinity and temperature, meanwhile this situation was vise-versa for blue-green algae with high abundance in warm months.

As pearling has been banned since 2006 in Persian Gulf, growth and mortality rate of Mohar pearl oyster in its old habitats was surveyed in present research. For early survey and identification of habitats of Mohar pearl oyster Pinctada radiata, primary sea tours in coastal waters of Lavan Island, were done. Two habitats were identified and sampled seasonally from autumn 2011 to summer 2012, to investigate Pinctada radiata stock condition. Belt transects and random quadrates method was used in this sampling. Infinity length, L∞, in Lavan No. 1 (Dardoor) and Lavan No. 2 (Hedabad) habitats was 89.16 and 87.68 mm. Growth constant, K, estimated 0.34 and 0.44 year-1in that two habitats. The amount of t0 for oysters in Dardoor and Hedabad habitats was -0.36 and -0.28 year and tmax was estimated equal to 8.46 and 6.54 year respectively. Natural mortality constant, M, was 0.63 and 0.75 year-1 respectively. Analyses of growth constant, K, revealed that this figure has decrease in these habitats in recent years. Investigation of recruitment plots indicated semi continuous pattern of recruitment in pearl oysters, demonstrating that reproduction occurs in almost throughout the year although two peaks of reproduction were observed in summer and winter.

Mohar pearl oyster Pinctada radiata is the dominant economic species of pearl oyster in the Persian Gulf, particularly along the Iranian coastal waters. As pearling has been banned since 2006, stocks of pearl oysters has not been investigated during these years. For this purpose, conditions of natural habitats and stocks of Mohar pearl oyster in its old catch sites were surveyed in the present study. Shallow waters around the Lavan island were searched through diving and two habitats of Mohar pearl oyster, namely Lavan No. 1 (Dardoor) and Lavan No. 2 (Hedabad), were detected. Area of Dardoor and Hedabad habitats was calculated equal to 60 and 15 ha, respectively and Mohar pearl oysters had the highest distribution in depth ranges of 7 to 12 m and 5 to 11 m, respectively. Total stocks of Dardoor and Hedabad habitats was surveyed about 357000 and 61500 pearl oysters of which 11% and 17% of oysters were catchable, respectively. Catch per unit of area in Dardoor and Hedabad habitats was estimated equal to 0.6 N/m2 and 0.4 N/m2 and catch per unit of effort was calculated equal to 119 N/hr and 82 N/hr, respectively. Biomass rate in these habitats was obtained equal to 4620 and 1163 kg, respectively. Results of this research revealed that the area, the amount of stocks and catch per unit of area of habitats has decrease in the recent years. Although the pearling has been banned in this region in the past seven years, restocking has been conducted slowly.