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This is the first report on using Catathelasma ventricosum for production of fruiting body and lignocellulosic enzymes. To improve the laccase activity and productivity of mushroom, the substrate was added with different supplements (eight aromatic compounds, Mn2+, and Cu2+). Based on the results, all these supplements can improve the laccase activity and productivity of C. ventricosum, and it seems that there is a critical value of laccase activity that affects the productivity of C. ventricosum. In addition, when Penicillium decumbens was inoculated into the substrate that had been cultivated with C. ventricosum for 20 days, the highest values of laccase activity, FPA activity, and productivity of C. ventricosum were obtained. Moreover, the laccase activity showed a positive correlation with the productivity of C. ventricosum. Finally, the effect of Mn2+, Cu2+, and P. decumbens on laccase activity was investigated by response surface methodology (RSM).

Functional immobilized metal affinity magnetic carboxymethyl chitosan nanoparticles (abbreviated as Fe(3)O(4) (PEG+CM-CTS) @ Fe (III)) were conveniently applied for phosvitin phosphopeptides (PPPs) enrichment for the first time. The morphology of magnetic nanoparticles was observed by transmission electron microscope (TEM). It was found that the diameter of Fe(3)O(4) (PEG+CM-CTS) @ Fe (III) was about 20 nm, and could easily aggregate by a magnet when suspending in the aqueous solution. In the PPPs enrichment study, the results obtained emphasized the role of pH, temperature and the initial concentration of the peptides solution in governing the efficiency and mechanism of affinity interactions. Due to the large specific surface area, the enrichment of PPPs onto the Fe(3)O(4) (PEG+CM-CTS) @ Fe (III) nanoparticles was promising. The adsorption equilibrium of PPPs onto the obtained magnetic nanoparticles fitted well with the Langmuir model, and the nitrogen/phosphorus molar ratio (N/P) which at the maximum enrichment capacity for PPPs was 4.83. Due to the small diameter, the decrease of the N/P is particularly rapid in the early enrichment stages (0-30 min) to reach a plateau after 60 min. Compared with traditional methods, the need for preparation of phosvitin before purification is obviated and PPPs of higher purity were obtained. Since the preparation, surface modification and affinity separation processes of the magnetic nanoparticles are cost-effective, convenient and efficient, this type of Fe(3)O(4) (PEG+CM-CTS) @ Fe (III) nanoparticles would bring advantages compared to conventional separation techniques of PPPs from chicken egg yolk, as well as for phosphopeptides enrichment in proteomics research., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Functionalized Fe(3)O(4) nanoparticles conjugated with polyethylene glycol (PEG) and carboxymethyl chitosan (CM-CTS) were developed and used as a novel magnetic absorbing carrier for the separation and purification of lysozyme from the aqueous solution and chicken egg white, respectively. The morphology of magnetic CM-CTS nanoparticles was observed by transmission electron microscope (TEM). It was found that the diameter of superparamagnetic carboxymethyl chitosan nanoparticles (Fe(3)O(4) (PEG+CM-CTS)) was about 15 nm, and could easily aggregate by a magnet when suspending in the aqueous solution. The adsorption capacity of lysozyme onto the superparamagnetic Fe(3)O(4) (PEG+CM-CTS) nanoparticles was determined by changing the medium pH, temperature, ionic strength and the concentration of lysozyme. The maximum adsorption loading reached 256.4 mg/g. Due to the small diameter, the adsorption equilibrium of lysozyme onto the nanoparticles reached very quickly within 20 min. The adsorption equilibrium of lysozyme onto the superparamagnetic nanoparticles fitted well with the Langmuir model. The nanoparticles were stable when subjected to six repeated adsorption-elution cycles. Separation and purification were monitored by determining the lysozyme activity using Micrococcus lysodeikticus as substrate. The lysozyme was purified from chicken egg white in a single step had higher purity, as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Considering that the superparamagnetic nanoparticles possess the advantages of high efficiency, cost-effectiveness and excellent binding of a larger amount of lysozyme and easier separation from the reaction system, thus this type of superparamagnetic nanoparticles would bring advantages to the conventional separation techniques of lysozyme from chicken egg white., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Antimicrobial photodynamic therapy is a recently developed therapeutic option that combines a non-toxic photosensitizer with harmless visible light to damage the microbial cell. Hypocrellin A (HA), a natural occurring lipid-soluble perylenequinone pigment, has gained considerable interest since its anticancer and antiviral activities have been reported. Here, we examined the antimicrobial activity of HA against Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative bacteria (Escherichia coli, Salmonella typhimurium). The results indicate that HA has a photodynamic antimicrobial activity against both Gram-positive and Gram-negative bacteria when CaCl(2) or MgCl(2) was employed. A loose binding has been established between HA and the organisms. Molecular oxygen is significantly involved in the photodynamic action of HA. Furthermore, HA maintains a photodynamic activity in terms of both types I and II reactions. Our results confirm the potential of HA to be used as a photosensitizer in antimicrobial photodynamic therapy., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The design and expression of an antihypertensive peptide multimer (AHPM), a common precursor of 11 kinds of antihypertensive peptides (AHPs) tandemly linked up according to the restriction sites of gastrointestinal proteases, were explored. The DNA fragment encoding the AHPM was chemically synthesized and cloned into expression vector pGEX-3X. After an optimum induction with IPTG, the recombinant AHPM fused with glutathione S-transferase (GST-AHPM) was expressed mostly as inclusion body in Escherichia coli BL21 and reached the maximal production, 35% of total intracellular protein. The inclusion body was washed, dissolved, and purified by cation exchange chromatography under denaturing conditions, followed by refolding together with size exclusion chromatography and gradual dialysis. The resulting yield of the soluble GST-AHPM (34 kDa) with a purity of 95% reached 399 mg/l culture. The release of high active fragments from the AHPM was confirmed by the simulated gastrointestinal digestion. The results suggest that the design strategy and production method of the AHPM will be useful to obtain a large quantity of recombinant AHPs at a low cost.