Monitoring Movement Behaviour of Caenorhabditis elegans in Response to Formaldehyde at Low Concentrations

Abstract.-This study describes a new approach for assessing toxic response behaviour of Caenorhabditis elegans by automatic recognition of line movement through an image-processing system. The movement behaviour of this nematode is different even at low concentrations of formaldehyde. A comparison of the response behaviour of this animal at different concentrations of formaldehyde has shown concentration-dependent toxicity. This study has identified some sequential line-movements on nematodes that confirmed the toxicological effect on nematode behaviour

Box–Behnken Response Surface Design of Polysaccharide Extraction from Rhododendron arboreum and the Evaluation of Its Antioxidant Potential

© 2020 by the authors. In the present investigation, the ultrasound-assisted extraction (UAE) conditions and optimization of Rhododendron arboreum polysaccharide (RAP) yield were studied by a Box–Behnken response surface design and the evaluation of its antioxidant potential. Three parameters that affect the productivity of UAE, such as extraction temperature (50–90 ◦C), extraction time (10–30 min), and solid–liquid ratio (1–2 g/mL), were examined to optimize the yield of the polysaccharide percentage. The chromatographic analysis revealed that the composition of monosaccharides was found to be glucose, galactose, mannose, arabinose, and fucose. The data were fitted to polynomial response models, applying multiple regression analysis with a high coefficient of determination value (R2 = 0.999). The data exhibited that the extraction parameters have significant effects on the extraction yield of polysaccharide percentage. Derringer’s desirability prediction tool was attained under the optimal extraction conditions (extraction temperature 66.75 ◦C, extraction time 19.72 min, and liquid–solid ratio 1.66 mL/g) with a desirability value of 1 yielded the highest polysaccharide percentage (11.56%), which was confirmed through validation experiments. An average of 11.09 ± 1.65% of polysaccharide yield was obtained in optimized extraction conditions with a 95.43% validity. The in vitro antioxidant effect of polysaccharides of R. arboreum was studied. The results showed that the RAP extract exhibited a strong potential against free radical damage

Length–Weight Relationships of Twelve Fishes from the River Padma nearRajshahi City, Bangladesh

International audienc

Length–Weight Relationships of Twelve Fishes from the River Padma nearRajshahi City, Bangladesh

International audienc

Heavy Metal Concentration in Two Freshwater Fishes from Wadi Hanifah (Riyadh, Saudi Arabia) and Evaluation of Possible Health Hazard to Consumers

Abstract.-The contamination of heavy metals, such as chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), cadmium (Cd) and lead (Pb) were evaluated in the water and tissues of African catfish Clarias gariepinus and Sabaki tilapia Oreochromis spilurus from Wadi Hanifah, Riyadh. The samples were collected from three sampling sites (Namar, Al-Masani and Al-Hair) of Wadi Valley of central Saudi Arabia during May-June 2013. The water and fish samples collected from Al-Masani, nearby a vehicle mechanical industrial area, were found to be more contaminated by Cr, Fe, Zn and Pb than those of other sampling sites. The high concentrations of Fe were detected in all the water and fish samples, followed by Zn, Pb, Cr, Co, Ni and Cd. However, none of the detected HM (heavy metals) concentrations were exceeded the permissible limits set by the different authorities. The estimated daily intake was found to be below the provisional tolerable daily intake (PTDI), established by the FAO and WHO, indicating that there was no carcinogenic risk for humans

Investigation on the Genotoxicity of Mercuric Chloride to Freshwater Clarias gariepinus

The cytogenetic effect of heavy metal was studied in Clarias gariepinus using the micronucleus test, chromosomal aberrations and sister chromatid exchange. The fish were kept separately and treated with four different concentrations of mercuric chloride for a period of 7 days. For the micronucleus test blood samples were obtained from the caudal vein. The mean micronuclei frequencies were recorded as 0.20, 0.25, 0.50, 0.65 and 0.79 in controls and 1.0, 2.0, 4.0 and 6.0 ppm in groups treated with mercuric chloride, respectively. Kidney tissues were used for in vivo chromosome preparation. The mean frequencies of cells with chromosomal aberrations were 0.21, 0.32, 0.49, 0.70 and 0.97 in the control and 1, 3, 5 and 7 ppm in groups treated with mercuric chloride, respectively. Similarly, the mean frequencies of sister chromatid exchange were recorded as 0.10, 0.28, 0.47, 0.58 and 0.64 in controls and 1, 3, 5 and 7 ppm in groups treated with mercuric chloride, respectively. The findings of present experiment suggest that HgCl2 caused genotoxic effects in fish