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Showing 3 results for Sinaei
Temperature-Based Prediction of Sex Ratio in Hatchlings Green Sea Turtle (Chelonia mydas)

Volume 6, Issue 4 (Fall 2018)
Abstract
Aims: It has been shown that sea turtles have temperature-dependent sex determination. Therefore, their sex determination is useful in understanding their reproduction ecology and population status. The aims of the present study were to estimate the sex ratio and to study the effect of inundation on the sex ratio of the hatchling green sea turtle (Chelonia mydas).
Materials & Methods: This experimental study was carried out on the 300km of Chabahar Beach on the northern coast of the Sea of Oman in July to December, 2015. Five areas which have the highest densities of nesting green sea turtles were chosen. The temperature of three different depths of green sea turtle clutches laid (50cm; above the egg hole, 85cm; center of egg hole and 120cm; below the egg hole) were recorded using automated intra-nest recording devices. Linear Regression Analysis and Pearson correlation coefficient were used. Statistical analyses of the data were conducted by SPSS 20 and Microsoft Office Excel 2010.
Findings: The statistical mean temperature in thermosensitive period (TSP) of the nests at three depths of 50cm, 85cm, and 120cm at the chabahar beaches were recorded between 26.1±1.1 to 30.6±1.0. The storm had decreased the mean temperature in thermosensitive period of the nests.
Conclusions: The storm decreases the mean temperature in thermosensitive period of the nests. The Nilofar storm stops the increasing feminization. It can be an important step in the implementation of conservation, rehabilitation, and reconstruction programmers.

Study of changes in metallothionein concentration of ghost crab (Ocypode saratan) in Gwater and Chabahar mangrove forests in two periods of pre-monsoon and post-monsoon

Volume 9, Issue 4 (11-2020)
Abstract
 The aim of this study was to compare the accumulation of heavy metals copper, zinc and cadmium and to investigate the changes of metallothionein as a biomarker of contamination in the gill tissue of the ghost crab Ocypode saratan in the two time periods before Monsoon (May) and after Monsoon (November) in mongrove forests. Chabahar and Gwater Bay was done in 2019. The results of the study showed that in both pre-Monsoon and post-Monsoon seasons the pattern of metal accumulation in the gill tissue of the ghost crab is zinc, copper, cadmium.The mean concentrations of copper, zinc and cadmium were obtained in the pre-monsoon and post-monsoon seasons at Chabahar station, 173.6 ± 3.83, 186.43 ± 3.1, 0.095 ± 0.008, respectively and 156.7±4.15 ،175.13 ± 2.8, 0.026 ±0.003 and in Gwater station the average concentrations of copper, zinc, cadmium in the two pre-Monsoon and post-Monsoon seasons were respectively 237.03 ± 6.4, 231.8 ± 1.8, 0.048 ± 0.003 and 205.9 ± 6.34, 253.2 ±  2.13, 0.037 ± 0.015 μg/g dry weight. The mean levels of metallothionein in pre-monsoon and post-monsoon season in Chabahar station were 2.02 ± 0.01 and 0.1 ± 0.06, respectively, and in goiter station were 2 ± 0.02 and 0.12 ± 0.02, respectively. Comparison of metallothionein levels between Chabahar and Gwater stations was not significant (P<0.05). But in both stations separately between the two pre-Monsoon and post-Monsoon seasons, there was a significant difference (P<0.05). Correlation between metallothionein and metals showed that there was no correlation between metallothionein and the studied metals. Therefore, according to the observations, changes in the concentration of metallothionein in this species are not affected by heavy metals and can be due to changes in the environmental conditions of the seasons.
Screening of isolated bacteria from Persian Gulf petroleum sediments with capability of poly hydroxybutyrate production and identification of the physicochemical structure of the produced biopolymer
Neda Sinaei, Davod Zare, Mehrdad Azin,
Volume 12, Issue 1 (12-2020)
Abstract
Background and Objective: Polyhydroxyalkanoates (PHAs) are polymers with biodegradable and biocompatible properties that are produced by some bacteria. In the present study, petroleum sediments were applied to screen PHA-producing bacteria.
Method: The industrial culture medium of petroleum effluent was used as a low-cost and economical medium for isolating and identifying the superior PHA-producing strain. Finally, the chemical and physical properties of the extracted biopolymer were investigated by Fourier-transform infrared spectroscopy, differential scanning calorimetry, and proton nuclear magnetic resonance.
Results: In general, 11 out of 76 isolated bacterial strains could produce biopolymers among which, the Sb8 strain was selected as the best PHA-producing strain in the industrial medium with the cell dry weight of 44.13% and 1.2 g/l in 27 h. This strain was identified as Citreicella thiooxidans by sequencing determination. Eventually, the results of physicochemical analyses revealed that polyhydroxybutyrate (PHB) was the extracted biopolymer.
Conclusion: The present study is the first report on PHB production by Iranian native Citreicella thiooxidans strain by focusing on identifying and separating producing bacteria, as well as determining the type of the produced biopolymer and the production capability in a low-cost culture medium of the petroleum effluent. Considering the production of the biopolymer with a relatively high yield percentage without adding any supplement to the petroleum effluent medium, the isolated wild strain has the potential to produce PHB.

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