COMPARATIVE ANALYSIS OF DNA ISOLATED FROM FISH SAMPLES BY THREE DIFFERENT EXTRACTION PROTOCOLS

The studies on fish genetic diversity and its conservation in Nigeria are still at its preliminary stages. The country needs to document the diversities of all the water bodies and also embark on a DNA barcoding project for rapid identification of the enormous populations and consequent deposition in the global genebank for references. All molecular studies usually start with the isolation, purification, and recovery of DNA and this usually depends on the types of tissue, mode of sample collection, the medium of storage, duration of storage, and used extraction protocols. The current study embarked on fish collection in four major freshwater habitats as a preliminary study to a proposed fish barcoding project and to comparatively determine the extraction protocol that will be cost-effective, fast, safe, and yield adequate molecular materials for downstream amplification, cloning, and sequencing reactions. In the current study, three DNA extraction protocols, Zymo Research Kit (ZR), modified conventional SNET method, and modified Urea-SDS Method were compared to establish the best DNA extraction method from freshwater fishes. Sixty-two (62) fish samples were collected belonging to 16 different families, 23 Genera, and 32 Species. The average yield of the three protocols in terms of concentration (ng/μL: Purity) are: ZR (30.59: 1.58); UREA, (705.49: 1.75) and SNET (562.22: 1.73). Hence, in terms of DNA concentration recovery, the sequence of the best method is UREA &gt; SNET &gt; ZR, and the same trend followed in the case of Purity. Statistical tests did not show any significant difference when the extraction protocols were compared among fish families. Cytochrome B gene was successfully amplified on the DNA template to confirm their suitability for further studies. The result of the study can be concluded that among the best DNA extraction methods, UREA protocol can be recommended for fish DNA extraction, this is not only cost-effective, but also gave quality yield and adequate for downstream analysis.</jats:p

Decreased motility of flagellated microalgae long-term acclimated to CO2-induced acidified waters

Motility plays a critical role in algal survival and reproduction, with implications for aquatic ecosystem stability. However, the effect of elevated CO2 on marine, brackish and freshwater algal motility is unclear. Here we show, using laboratory microscale and field mesoscale experiments, that three typical phytoplankton species had decreased motility with increased CO2. Polar marine Microglena sp., euryhaline Dunaliella salina and freshwater Chlamydomonas reinhardtii were grown under different CO2 concentrations for 5 years. Long-term acclimated Microglena sp. showed substantially decreased photo-responses in all treatments, with a photophobic reaction affecting intracellular calcium concentration. Genes regulating flagellar movement were significantly downregulated (P P D. salina and C. reinhardtii showed similar results, suggesting that motility changes are common across flagellated species. As the flagella structure and bending mechanism are conserved from unicellular organisms to vertebrates, these results suggest that increasing surface water CO2 concentrations may affect flagellated cells from algae to fish

An Inexpensive and Sensitive Method for Speciative Determination of Sn(IV), Sn(II), and Total Sn as Sn(IV) in Selected Beverages by Micellar Improved Spectrophotometry

Springer New York LLCIn the present study, an inexpensive, selective, and micellar sensitive spectrophotometric method for Sn(IV) was developed at 537 nm. The method is based on the formation of ternary complex of Sn(IV) with tartaric acid and Celestine blue in the presence of sodium dodecyl sulfate (SDS) and polyethylene glycol tert-octylphenyl ether (Triton X-114) at pH 3.5. The analytical variables affecting cloud point extraction (CPE) efficiency were optimized in detail. Under the optimized conditions, the calibration graph was linear in the range of 4–350 ?g L?1 with changing dye concentration for Sn(IV) ions. The limits of detection and quantification of the method were found to be 1.3 and 4.3 ?g L?1 for Sn(IV), respectively. Relative standard deviation (RSDs) for five replicate determinations at 20 and 100 ?g L?1 concentration levels were 4.4 and 1.5 %, respectively. Recovery values of spiked samples were obtained in range of 97.7–103.3 %. Matrix effect on the extraction efficiency were also investigated. The method was successfully applied to the determination of Sn(II), Sn(IV) and total Sn in some selected beverages before and after pretreatment with H2O2 in acidic media, prior to analysis. Validity of the method was controlled through the analysis of two certified reference materials. It has been observed that the results are highly compatible with the certified values. © 2014, Springer Science+Business Media New York.Altunay, N.; Department of Chemistry, University of CumhuriyetTurkey; email: [email protected]