Electrochemical Biosensor for Protein Concentration Monitoring Using Natural Wood Evaporation for Power Generation.

A high-sensitivity, low-cost, self-powered biomass electrochemical biosensor based on the "evaporating potential" theory is developed for protein detection. The feasibility of experimental evaluation methods was verified with a probe protein of bovine serum albumin. The sensor was then used to detect lung cancer marker CYFRA21-1, and the potential of our sensor for clinical diagnosis was demonstrated by serum analysis. This work innovatively exploits the osmotic power generation capability of natural wood to construct a promising electrochemical biosensor that was driven by kinetics during testing. The detection methods used for this sensor, chronoamperometry and AC impedance, showed potential for quantitative analysis and specific detection, respectively. Furthermore, the sensor could facilitate new insights into the development of high-sensitivity, low-cost, and easy-to-use electrochemical biosensors.

A simple and effective dansyl acid based "turn-on" fluorescent probe for detecting labile ferrous iron in physiological saline and live cells.

Labile ferrous iron (Fe2+) plays important biochemical functions in many physiologically essential processes. It is very important to find an effective method to detect Fe2+. Herein, a simple and effective Fe2+ fluorescent probe (FeP1) has been constructed via a unique strategy of Fe2+-induced reducing reaction. As expected, FeP1 exhibited a 'turn-on' fluorescence response toward Fe2+ over various small analytes, with high selectivity and excellent sensitivity (DL = 18 nM) for the detection of Fe2+ in Tris-DMSO (4:1, pH = 7.4, v/v) solution. Moreover, the probe can act in different real samples, such as physiological saline and living cells.

Extraction optimization and bioactivities of an extracellular polysaccharide produced by Aspergillus fumigatus.

Aspergillus fumigatus produces an extracellular polysaccharide, AFEPS, when grew in NaOH solution pretreated rice-straw medium. A three-level, three-factor Box-Behnken design (BBD) response surface methodology (RSM) was applied to optimize the extraction parameters of AFEPS. RSM analysis indicated good correspondence between experimental and predicted values. The optimal conditions for polysaccharide were: precipitation time 10.9h, pH 5.2 and ethanol concentration 90%. AFEPS was composed of arabinose, xylose and glucose in a molar ratio of 1.05:5.36:10.83, its average molecular weight was estimated to be about 36.2kDa. Evaluation of the antioxidant activity in vitro suggested that AFEPS had high scavenging activity for superoxide anion and hydroxyl radicals. AFEPS exhibited excellent antitumor activities both in vitro and in vivo while showing no damage to normal cells.

Laccase production optimization by response surface methodology with Aspergillus fumigatus AF1 in unique inexpensive medium and decolorization of different dyes with the crude enzyme or fungal pellets.

In the present study, alkaline pretreatment was applied for the enhanced laccase production from rice straw. Various process parameters including sodium hydroxide concentration, pH and fermentation temperature were optimized via response surface methodology (RSM) with a Box-Behnken design (BBD). Through regression analysis, it was found that laccase activity was well fitted by a quadratic polynomial equation (R(2)=0.998, Adj R(2)=0.995), and the fermentation temperature was the most significant factor influencing laccase activity. The optimized process conditions found were NaOH concentration of 0.39 mol L(-1), pH 3.12 and temperature 25.43 °C, under which laccase activity reached 142,198 ± 3586 U L(-1). Further studies were carried out to probe different dyes decolorization ability of laccase produced by Aspergillus fumigatus, A. fumigatus pellets and whole fermentation broth (WFB) using sodium hydroxide pretreated rice straw as sole carbon source. Results showed that pure laccase demonstrate limited decolorization ability to all the studied dyes, while crude laccase, A. fumigatus pellets and WFB exhibit significant decolorization ability to all the studied dyes with WFB being the most excellent one. Effectiveness of degradation was confirmed by uv-vis and phytotoxicity studies, which indicated that A. fumigatus transformed the dyes into non-toxic metabolites.

Extraction optimization and bioactivity of polysaccharides from Aspergillus fumigatus AF1.

Aspergillus fumigatus was used to produce polysaccharide using sodium hydroxide pretreated rice straw as the sole carbon source by submerged fermentation. Response surface methodology (RSM) was used to optimize the extraction of polysaccharide from the mycelia of A. fumigatus (PAF). A three-level, three-factor Box-Behnken design (BBD) was applied for experimental design and analyzed the results to obtain the optimal extraction parameters. RSM analysis indicated good correspondence between experimental and predicted values. The optimal conditions for polysaccharide extraction were extraction temperature 50°C, extraction time 6h, ratio of dried mycelia mass to water 0.03. PAF showed excellent antitumor activity in vitro and exert no damage to the normal cells. PAF also showed prominent antitumor activity in vivo against S180 and increased the spleen and thymus index significantly.

Antioxidant and antitumor activities of the polysaccharide from seed cake of Camellia oleifera Abel.

To explore biomedical potential of the polysaccharide from seed cake of Camellia oleifera Abel, we investigated antioxidant and antitumor capacities of the polymer. The results showed that the polysaccharide is capable of scavenging both superoxide anion and hydroxyl radicals in vitro. The highest scavenging rate of superoxide anion and hydroxyl radicals is 85% and 76%, respectively. Using the model animal, Caenorhabditis elegans, we further show that the polysaccharide can increase antioxidant enzyme activity, decrease lipid peroxidation level, and reduce paraquat-induced oxidative damage at a polysaccharide concentration more than 50mg/l. We also revealed that the polysaccharide has some ferric chelating ability and strong in vivo antitumor activity. The antitumor rate against Sarcoma180 solid tumor grown in BALB/C mice reached 85.6% at the highest dose of 40 × 20 mg/kg days.

A myxobacterium strain Sorangium cellulosum AHB125 producing epothilone B and other anticancer substances.

A myxobacterium strain AHB125 belonging to genus Sorangium cellulosum was isolated from Anhui area in China and identified with morphological analysis by electron microscopy and phase contrast microscope according to Bergey's manual of systematic bacteriology (8th Ed.). Its high-antitumor bioactivity metabolites was evaluated by bioassay-directed screening technique with B16 tumor cell line etc. Research results showed that it exhibited not only strong antitumor ability bioactivities and broad-spectrum antitumor abilities to B16, Bel7402, H446, SGC7901 cell lines, but also has selectivity and pertinence to B16 and SGC7901 cell lines. The compound was confirmed as epothilone B by HPLC and LC/MS analysis, compared to the epothilone B standard sample. Bioassay indicated that there were other high-bioactive substances in the metabolites.

Decolorization of a dye industry effluent by Aspergillus fumigatus XC6.

The strain Aspergillus fumigatus XC6 isolated from mildewing rice straw was evaluated for its ability to decolorize a dye industry effluent. The strain was capable of decolorizing dyes effluent over a pH range 3.0-8.0 with the dyes as sole carbon and nitrogen sources. The optimum pH was 3.0; however, supplemented with either appropriate nitrogen sources (0.2% NH(4)Cl or (NH(4))(2)SO(4) ) or carbon sources (1.0% sucrose or potato starch), the strain decolorized the effluent completely at the original pH of the dyes effluent. Therefore, A. fumigatus XC6 is an efficient strain for the decolorization of reactive textile dyes effluents, and it might be a practical alternative in dyeing wastewater treatment.