Novel liquid fermentation medium of Cordyceps militaris and optimization of hydrothermal reflux extraction of cordycepin.

In this study, we developed a novel liquid fermentation medium of Cordyceps militaris using pupa powder and wheat bran as nitrogen resources instead of the traditionally used peptone. This process not only reduced the cost by approximately 50%, but increased production by over 30%. Then, we explored a method to extract and purify cordycepin by combining hydrothermal reflux extraction with macroporous resin adsorption, which is inexpensive and suitable for the industrial production. The optimum conditions for hydrothermal reflux were extracting three times at 95 °C with 1:10 sample-to-water ratio, and the cordycepin purity with macroporous resin HPD-100 reached 95.23%.[Formula: see text].

Properties comparison between free and immobilized wheat esterase using glass fiber film.

In this paper, the catalytic performance of non-purified esterase from wheat bran immobilized on glass fibre membrane carrier is established, the immobilization conditions observed were enzyme 1 mL, phosphate buffer 3 mL (pH 7.0), immobilization time 1 h, immobilization temperature 29 °C. After carrier functionalization some characteristics of immobilized enzyme were studied, the results showed that immobilized enzyme presenting improved characteristic than that of free enzyme. The optimum pH for free and immobilized enzymes were found to be 8 and 7, respectively. As for optimum temperature for free and immobilized enzymes were observed to be 30 °C and 40 °C, respectively. When the enzyme was immobilized on glass fibre membranes, its Km increased about 7 times. In addition, storage and thermal stability of the free wheat esterase were increased by as a result of membrane immobilization, after 12 days of storage, the immobilized enzyme still retained about 91.10% of its original activity at 4 °C, indicating a great potential in industrial application.