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1.
Sci Rep ; 12(1): 14322, 2022 08 22.
Article in English | MEDLINE | ID: mdl-35995829

ABSTRACT

Coastal vulnerability assessment is the key to coastal management and sustainable development. Sea level rise (SLR) and anthropogenic activities have triggered more extreme climatic events and made the coastal region vulnerable in recent decades. Many parts of the world also noticed increased sediment deposition, tidal effects, and changes in the shoreline. Farasan Island, located in the south-eastern part of Saudi Arabia, experienced changes in sediment deposition from the Red Sea in recent years. This study used Digital Shoreline Analysis System (DSAS) to delineate the shoreline changes of Farasan Island during 1975-2020. Multi-temporal Landsat data and DSAS were used for shoreline calculation based on endpoint rate (EPR) and linear regression. Results revealed an increase in vegetation area on the island by 17.18 km2 during 1975-1989 and then a decrease by 69.85 km2 during 1990-2020. The built-up land increased by 5.69 km2 over the study period to accommodate the population growth. The annual temperature showed an increase at a rate of 0.196 °C/year. The sea-level rise caused a shift in the island's shoreline and caused a reduction of land by 80.86 km2 during 1975-2020. The highly influenced areas by the environmental changes were the north, central, northwest, southwest, and northeast parts of the island. Urban expansion and sea-level rise gradually influence the island ecosystem, which needs proper attention, management, policies, and awareness planning to protect the environment of Farasan Island. Also, the study's findings could help develop new strategies and plan climate change adaptation.


Subject(s)
Ecosystem , Global Warming , Climate Change , Indian Ocean , Saudi Arabia
2.
Saudi J Biol Sci ; 28(1): 125-134, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33424289

ABSTRACT

The main objective of this work is to analyze the perinatal protective effects of curcumin (Cur) on the toxicity of inorganic mercury (mercuric chloride - HgCl2) in the developing mice offspring on their behavioral and biochemical changes. Six groups of pregnant mice (consisting of ten animals in each) were allocated in a way that Group I consuming tap water was used as control. Groups II to VI were the experimentally treated groups in which Group II and III received 150 and 300 ppm of curcumin, respectively; Group IV was given 10 ppm of HgCl2; and Group V and VI were also exposed to 10 ppm of HgCl2 but concurrently they were also treated with 150 and 300 ppm of curcumin, respectively. Appearance of vaginal plug was considered as the first day of pregnancy and all treatment started from day one of pregnancy until post-natal day 15 (PD 15) and the mothers were switched to plain tap water thereafter. At the age of PD 40, the male pups were subjected to measuring the depression in the light-dark chambers, forced swimming and tail suspension tests and to measuring their anxiety in plus-maze and open-field tests. Subsequently, after behavioral tests, the levels of corticosterone and cortisol hormones were estimated in the plasma of the experimental offspring. Behavioral tests were measured in the HgCl2 treated offspring for the light-dark chambers; forced swimming test; tail suspension test; plus-maze test; and open -field test showed significant alterations in their depression, anxiety and locomotory activities. Biochemical estimation of corticosterone and cortisol hormones in the plasma of these offspring showed significant depletion in their levels. Treatment of these offspring with curcumin significantly and dose dependently ameliorated all the behavioral and biochemical disruptive effects in the offspring due to HgCl2 toxicity. In conclusion, curcumin ameliorates the toxic effects of HgCl2 in the offspring during gestation and lactation periods. Thus, exposure to HgCl2 to mothers during pregnancy needs careful monitoring for minimizing its toxicity. Curcumin appears to be a promising ameliorating agent for such HgCl2 toxicity; however, further studies are needed for establishing these preliminary findings.

3.
Saudi J Biol Sci ; 26(5): 963-969, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31303826

ABSTRACT

The impacts of unnatural every day cycles (circadian) for 60 days on the histological structure of kidneys and ATPase activities in MF1 mice were studied. The exposure times were 16 h dark, 16 h light, 24 h dark, and 24 h light, and control exposure times were 12 h dark followed by 12 h light. Our results showed an increase in the total ATPase activity of mice in all groups. Additionally, the activity of the enzyme Na+/K+-ATPase was increased after 24 h darkness, 24 h light, and 16 h light exposures compared to control. The enzyme Mg+2-ATPase activities of the groups were higher when exposed to 16 h light, 24 h light, 24 h darkness and 16 h darkness. The activities of total ATPase, Na+/K+-ATPase and Mg+2-ATPase in kidneys were increased in all groups after 24 h light, 24 h darkness, 16 h darkness and 16 h light exposures. Interestingly, the activity of V-type ATPase was reduced after 16 h darkness, 24 h darkness and 16 h light. Taking everything into account, changes in the day by day cycle prompt neurotic changes, enzymatic and histological changes in the kidneys of mice. More studies should be directed to explore the impacts of light and darkness that can prompt these progressions.

4.
J Water Health ; 17(4): 622-632, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31313999

ABSTRACT

Drinking water quality plays a remarkable role in human infections and diseases. This study used polymerase chain reaction (PCR) techniques to detect bacterial pathogens. In addition, a physicochemical analysis was performed on drinking water samples from several sources. A total of 123 drinking water samples were collected from different areas in the Jazan region in Saudi Arabia: ground water (40 samples), bottled water (15 samples), tap water (52 samples), and water purification shops (16 samples). To isolate the bacterial pathogens, the water samples were spread on Nutrient and MacConkey agar media, and the grown pathogens were then identified by the 16S ribosomal RNA technique. In 87 (70.7%) of the 123 drinking water samples, there was no pathogen growth on the two-culture medium. However, 36 (29.3%) of the samples were found to be contaminated with bacteria. The physicochemical analysis indicated that the water samples were within the Saudi drinking water standards. The bacteria were resistant to Cefotaxime, Cefotaxime/Clavulanic acid, Erythromycin, Penicillin G, Rifampin and Sulfamethoxazole-Trimethoprim, respectively. The findings suggest that in Jazan, bottled water is a safer source of potable water than tap water. The contamination in the water may be occurring at the reservoirs rather than the water sources.


Subject(s)
Drinking Water , Humans , Saudi Arabia , Water Microbiology , Water Quality , Water Resources
5.
Saudi J Biol Sci ; 26(4): 866-871, 2019 May.
Article in English | MEDLINE | ID: mdl-31049016

ABSTRACT

Increased consumption of fossil fuels is an emerging problem. Scientists look for the existence of other alternatives to fossil fuels, including so-called renewable energy. Accordingly, we report the production of bio-ethanol from the remnants of castor oil bean seed cake (CBC) by the carboxymethylcellulase enzyme (CMCase). A bacterial strain isolated from rice straw showing higher CMCase activity was identified. The 16S rRNA result showed a 93% homology with the 16SrRNA gene sequences of Pseudomonas poae RE∗1-1-14, the strain was identified as Pseudomonas poae AB3. In addition, our results showed that the highest enzyme activity was achieved after 48 h and inoculum size of 3.7 × 105 CFU. The optimum temperature, pH and Carboxymethylcellulose (CMC) concentration for the highest enzyme activity was 25 °C, pH 7 and 10 g/l respectively. Furthermore, The CMCase was purified by ammonium sulphate at a concentration of 60%. The SDS-PAGE of the purified enzyme showed a molecular weight of 88 kDa. Additionally, the (CBC) was hydrolyzed by the purified CMCase at the enzyme optimum conditions. The results showed the liberation of 5.2 g/L of reducing sugar by using dinitrosalicylic acid (DNS) assay. Finally, the total sugar produces 35 g/L after 48 h when Saccharomyces cerevisiae was used as a fermentation agent. Hence for the first time, we have been successfully able to produce bioethanol from CBC with CMCase of Pseudomonas poae.

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