Evaluation of Pterin, a Promising Drug Candidate from Cyanide Degrading Bacteria.

Pterin is a member of the compounds known as pteridines. They have the same nucleus of 2-amino-4-hydroxypteridine (pterin); however, the side-chain is different at the position 6, and the state of oxidation of the ring may exist in different form viz. tetrahydro, dihydro, or a fully oxidized form. In the present study, the microorganisms able to utilize cyanide, and heavy metals have been tested for the efficient production of pterin compound. The soil samples contaminated with cyanide and heavy metals were collected from Salem steel industries, Tamil Nadu, India. Out of 77 isolated strains, 40 isolates were found to utilize sodium cyanate as nitrogen source at different concentrations. However, only 13 isolates were able to tolerate maximum concentration (60 mM) of sodium cyanate and were screened for pterin production. Among the 13 isolates, only 1 organism showed maximum production of pterin, and the same was identified as Bacillus pumilus SVD06. The compound was extracted and purified by preparative high-performance liquid chromatography and analyzed by UV/visible, FTIR, and fluorescent spectrum. The antioxidant property of the purified pterin compound was determined by cyclic voltammetry. In addition, antimicrobial activity of pterin was also studied which was substantiated by antagonistic activity against Escherichia coli, and Pseudomonas aeruginosa. Besides that the pterin compound was proved to inhibit the formation of biofilm. The extracted pterin compounds could be proposed further not only for antioxidant and antimicrobial but also for its potency to aid as anticancer and psychotic drugs in future.

Electrospun nylon 6,6 membrane as a reusable nano-adsorbent for bisphenol A removal: Adsorption performance and mechanism.

Bisphenol A (BPA) is highly considered as an emerging contaminants (ECs) due to their endocrine disrupting and reproductive toxicant nature. It has been detected in drinking water sources in many countries. This study deals with the adsorptive removal of BPA using nylon 6,6 nanofibrous membrane (NNM) fabricated by electrospinning technique. Langmuir and Freundlich isotherm models (R2=0.99) were obeyed for BPA adsorption, which indicates the monolayer adsorption of BPA and also surface heterogeneity of NNM. The adsorption kinetics of BPA was followed pseudo second order rate (R2=0.89-0.99), which suggests the occurrence of rapid adsorption rate through interaction of surface functional groups present in NNM. The maximum adsorption of BPA (91.3mgg-1) was attained at 30°C. The hydroxyl groups of BPA form hydrogen bonding with carbonyl groups of NNM during the adsorptive removal process. Reusability study confirmed a much better stability of NNM in the recyclic application. Finally, this study suggests that NNM might be an outstanding nano-adsorbent for the emerging contaminants removal, including BPA from drinking water sources.

Alteration of paraoxonase, arylesterase and lactonase activities in people around fluoride endemic area of Tamil Nadu, India.

BACKGROUND: Toxicity due to excess fluoride concentration in drinking water is of great concern in people who rely only on the ground water as their water source in many region of the world. METHODS: We collected samples and examined the toxicity of fluoride in a population residing at Salem, Dharmapuri and Krishnagiri districts of Tamil Nadu, India and measured HDL bound enzyme (PON1), erythrocyte membrane bound enzymes (acetylcholinesterase, AChE) and adenosine 5' triphosphatase (ATPases), plasma enzyme (butyrylcholinesterase, BChE) and rate limiting enzyme in heme biosynthesis (delta aminolevulinic acid dehydratase, δ-ALAD) activities. RESULTS: In fluorosis patients, formation of lipid peroxidation product was more in erythrocytes than in plasma. The observation further revealed that there was 50% reduction in the activity of HDL bound anti atherogenic enzyme-paraoxonase (PON1). The activities of membrane bound and signaling enzymes (acetylcholinesterase - AChE and adenosine 5' triphosphatase - ATPase) of erythrocyte were also diminished. These results suggested that there was defectiveness in the signaling and energy metabolism in fluorosis patients. Altered isoenzyme pattern of lactate dehydrogenase (LDH) in fluorosis samples was observed. Furthermore, the result suggested that both the heart (LDH 1) and liver (LDH 5) were most affected by fluoride toxicity. The study also provided reference values for tests which are used to predict the severity of fluoride toxicity. CONCLUSION: The toxic effect of fluoride was due to the collective effects on vital protective system rather than single factor.