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.

Simultaneous Determination of Eight Kinds of Neurotransmitters in Rat Blood Serum by Ultra-high Performance Liquid Chromatograph- Tandem Mass Spectrometry / 分析化学

An ultra-high performance liquid chromatography tandem mass spectrometric ( LC-MS/MS ) method for simultaneous determination of 8 kinds of neurotransmitters (5-HT, GABA, Glu, ACH, NE, DA, 5-HIAA, HVA) in rat serum was developed.The blood samples were extracted by 0.1% formic acid in acetonitrile and separated on a Waters ACQUITY UPLC BEH C18(2.1 mm×100 mm, 1.7 μm) using gradient elution, with the mobile phase consisting of acetonitrile and 0.1% formic acid in water.The samples were then ioniZed with positive electrospray ( ESI+) , and detected under multiple reaction monitoring ( MRM ) mode.As a result, 8 kinds of neurotransmitters were determined accurately in 10 min with a limit of quantitation of 1.8 ng/mL and intra-day and inter-day precisions of ≤9.2% ( n=6 ).This method showed a good linearity in detection of neurotransmitters and the linear correlation coefficients were greater than 0.994.Also the stability, recovery and matrix effect were eligible for the analysis.This method showed high accuracy, sensitivity, strong specificity, good stability, small matrix effect and short time for analysis, and was suitable for the quantitative determination of monoamine, amino acids and acetylcholine neurotransmittes in rat serum.

Immunolocalization of Jian Carp (Cyprinus Carpio Var. Jian) Cathepsin B: Cloning, Expression, Characterization, and Antibody Preparation.

Cathepsin B (CatB) cDNA of 759 bp from Jian carp (Cyprinus carpio var. Jian) with amino acid similarity of 99.6% to common carp was cloned. The mature CatB was expressed in Escherichia coli BL21 transferred with vector CatB-pET-30a. It was purified and identified as a single band (29 kDa) on SDS-PAGE. Optimum CatB activity was observed at 40 °C and pH 5.5. Mouse anti-CatB polyclonal antibody with a high titer of 1:256000 was prepared successfully and shown to specifically recognize the antigen both in prokaryotic cells and in the tissues of Jian carp according to western blotting and immunohistochemistry results. Immunolocation analysis showed that CatB distribution at protein level varied among the tested tissues. The results presented in this study may provide a significant reference for future research on the inherent relationship between CatB and the quality of fish or fish products at both the gene and protein levels.