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Showing 2 results for Ion Exchange Chromatography
Hanieh Ataollahi, Mohaddeseh Larypoor, Minoo Sadri,
Volume 12, Issue 4 (12-2021)
Abstract
Summery
Lentinula edodes(Shitake) is one of the most popular species of edible/medicinal fungus due to its high content of protein, polysaccharide and unique aroma, which is ranked second in the world in terms of cultivation and consumption. Today, its effective compounds are used as adjunctive therapy along with chemical treatments. In this study, the culture medium, acidity and optimum growth temperature of Lentinula edodes (TMU340) mycelium were determined. Mycelium, fruiting body and whole fungi were lyophilized and the wet to dry weight ratio was obtained; Lentinan was extracted using hot water at 60°C, degassing by Sevage method and precipitation with pure ethanol at 4°C and purified by Ion exchange chromatography. Lentinan concentration was obtained by phenol-sulfuric acid test. Results, Optimum conditions including PDA and PDB media, 25°C and pH, 5.5 were determined. The wet to dry weight ratio was 10 to 1 in all samples. Lentinan concentrations after extraction and purification were 0.243, 0.103 and 0.148 mg/ml, respectively. As a result, this fungus can be useful in the production of a variety of metabolites and natural compounds without side effects such as Lentinan polysaccharide as a factor in boosting the immune system.
Volume 16, Issue 6 (11-2014)
Abstract
Application of chemical pesticides has increased significantly worldwide and has raised serious concerns about environmental pollutions. One of the encouraging trends to minimize pesticide risk is production of resistant plants containing toxic proteins against insect pests. Considering the importance of purification and characterization of digestive enzymes in the production of resistant plants, in this study an α-glucosidase from the Naranga aenescens Moore's midgut was purified by ammonium sulfate precipitation, ion exchange chromatography on DEAE-sepharose, and concentrating through ultrafiltration. The apparent molecular mass of the enzyme was 48 kDa determined by SDS-PAGE. The optimum pH and temperature of the enzyme were 6.0 and 45°C, respectively. The irreversible thermoinactivation of the enzyme showed that it was highly stable at 35ºC but moderately stable at 40 and 45ºC. Zn2+, Hg2+, Co2+ at 10 and 20 mM, and Ba+2only in 20 mM strongly inhibited the α-glucosidase activity. Ba2+ and Ca2+ only at 10 mM, EDTA and Hg22+ only at 20 mM and Mg2+ at 10 and 20 mM significantly increased the enzyme activity. The Km and Kcat values for the α-glucosidase were 0.54 mM and 3.62 min-1, respectively, when p-Nitrophenyl-α-D-glucopyranoside (pNαG) was used as a substrate.