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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Advanced Journal of Chemistry-Section A
- نوع مقاله: Journal Article
- کلمات کلیدی: Amylase,Enzyme, Excipient,Hydrolysis,Calixarene,Starch
- چکیده:
- چکیده انگلیسی: In the present study, water soluble 5, 17-bis[(N-methylglucamine)methyl]-25,26,27,28-tetrahydroxycalix[4]arene (3, as a highly efficient excipient material) was synthesized to immobilize α-amylase first time using the N-methylglucamine functionalities for excipient-enzyme complex formation at its para-positions. The excipient-α-amylase complex (4)was used for the starch degradation. The optimum apparent activity of 4 was determined at variable conditions such as the effect of pH (7.0), temperature (25°C) and initial concentration of enzyme (15 µL). Under such optimized parameters, the maximum 71% yield of enzyme was immobilized onto the functionalized calix[4]arene material (3). The catalytic properties of 4 were determined by comparing with free α-amylase. The complex 4 revealed high stability under sever conditions, i.e. high temperature and offers multiple reuses with little loss in enzyme activity due to higher α-amylase concentration has been protected by complex. In addition, the enzyme activity and the excipient-α-amylase complex were found to have extra characteristics as compared to the free α-amylase for starch hydrolysis with respect to its stability and reusability. These advantageous characteristics and low cost of material from which calixarene derivative was prepared, making it economically viable for starch degradation on industrial scale.
- انتشار مقاله: 14-06-1399
- نویسندگان: Irshad Ali Veesar,Shahabuddin Memon,Ranjhan Junejo,Imam Bakhsh Solangi
- مشاهده
- جایگاه : پژوهشی
- مجله: Advanced Journal of Chemistry-Section A
- نوع مقاله: Journal Article
- کلمات کلیدی: Batch Adsorption,Toxic metal ions,Calix[4]arene,Online adsorption
- چکیده:
- چکیده انگلیسی: Toxic metal pollution is one of the most persistent environmental problems globally. This study deals with the synthesis of the p -piperdinomethyl calix[4]arene attached silica (PAS) resin and to investigate their metal ions removal efficiency from water. In batch adsorption experiment PAS resin shows good adsorption efficacy for the Cu2+ and Pb2+ metal ions. To examine the adsorption mechanism and validate the experimental adsorption data the isotherm models were applied and adsorption of the Cu2+ and Pb2+ metal ions follow Freundlich isotherm model very well with good correlation coefficient. However, the adsorption energy calculated from the D-R isotherm was at the range of 9-14 KJ/mole which describes the ion exchange nature of resin. Furthermore, breakthrough capacity of column was calculated from online adsorption as 0.027 and 0.041 mmol/g-1 for Cu2+ and Pb2+, respectively. Furthermore, thermodynamics and kinetic study revealed that, the adsorption process spontaneity and endothermic that follows the pseudo 2nd order kinetic equation with good regression coefficient.
- انتشار مقاله: 11-12-1398
- نویسندگان: Ranjhan Junejo,Shahabuddin Memon,Fatih Durmaz,Ayaz Ali Ahmed,Fakhar Nisa Memon,Nida Shams Jalbani,Safia Sanam Memon,Asif Ali Bhatti
- مشاهده