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1.
《Bioscience, biotechnology, and biochemistry》2013,77(9):2006-2009
We cloned a gene for the iron sulfur protein (Ip) subunit from an edible mushroom, Lentinula edodes, and introduced a point mutation that confers carboxin resistance into it. The mutant gene successfully transformed L. edodes with high efficiency (9 transformants/2.5 μg vector DNA). Restriction enzyme-mediated integration (REMI) increased the transformation efficiency by about two-fold. 相似文献
2.
L. Pesciaroli M. Petruccioli F. Federici A. D'Annibale 《Journal of applied microbiology》2013,114(6):1750-1762
Aims
To investigate the effect of support and growth medium (GM) on Pleurotus ostreatus biofilm production, specific metabolic activity (SMA) and ultrastructure.Methods and Results
Biofilms were developed on membranes covering a broad range of surface properties and, due to the applicative implications of mixed biofilms, on standard bacterial GM in stationary and shaken culture. Hydrophilic (glass fibre, Duran glass and hydroxyapatite) and mild hydrophobic (polyurethane, stainless steel, polycarbonate, nylon) supports were more adequate for biofilm attachment than the hydrophobic Teflon. Among the GM, sucrose–asparagine (SA) was more conducive to biofilm production than Luria–Bertani and M9. GM was more influential than support type on biofilm ultrastructure, and a high compactness was evident in biofilms developed on SA. Biofilms on Duran glass were more efficient than planktonic cultures in olive‐mill wastewater treatment.Conclusions
The main effects of support and GM variables and their binary interactions on both biofilm production and SMA were all highly significant (P < 0·001): thus, the magnitude of the effect of each variable strongly depended on the level of the other one.Significance and Impact of the Study
There is a lack of basic information regarding physiology and ultrastructure of P. ostreatus biofilms. To our knowledge, this is the first attempt to fill this gap, thus representing a basis for future studies. 相似文献3.
4.
Vladimir Elisashvili Michel Penninckx Eva Kachlishvili Mikheil Asatiani Giorgi Kvesitadze 《Enzyme and microbial technology》2006,38(7):457-1004
It has been shown that the wood-rotting mushroom Pleurotus dryinus IBB 903 is able to effectively produce cellulases, xylanase, laccase, and manganese peroxidase in submerged fermentation of mandarin peels and tree leaves. Gradual increasing of lignocellulosic substrates concentration from 1 to 4–6% enhanced enzyme accumulation in culture liquid. A simple and inexpensive medium containing mandarin peels and yeast extract as sole carbon and nitrogen sources allowed simultaneous production of high levels of both hydrolases and oxidases by P. dryinus IBB 903. Supplementation of this medium by copper and manganese caused earlier and faster accumulation of laccase and manganese peroxidase increasing their yield by 1.5 and 7.5 times, respectively. In addition, by adding manganese to the medium it is possible to regulate the ratio of laccase and MnP in enzyme preparation. The presence of lignocellulosic substrate is the requisite for MnP production by P. dryinus IBB 903 since there was no production of MnP when mushroom has been cultivated in the synthetic medium with different carbon source. Among carbon source tested only utilization of glucose resulted to 21-fold increase of fungus laccase specific activity compared to control medium without carbon source. Carboxymethyl cellulase and xylanase appeared to be inducible enzymes. 相似文献
5.
5种珍稀食药用真菌活性提取物对果蝇寿命影响的研究 总被引:4,自引:0,他引:4
探讨了松茸、栎金钱菌、蜂窝菌、云芝、杏鲍菇活性提取物对果蝇寿命的影响,分别用这5种食药用真菌活性提取物各以5、20g/L的剂量加入培养基中培养果蝇,观察其对果蝇寿命的影响.结果表明,松茸、栎金钱菌、蜂窝菌、云芝、杏鲍菇的活性提取物能显著延长果蝇的平均寿命和半数死亡时间,其平均寿命延长率分别达23.96%、53.22%、23.09%、32.58%、20%.这提示松茸、栎金钱菌、蜂窝菌、云芝、杏鲍菇都具有良好的延寿效果. 相似文献
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7.
An in vitro study was performed to determine the acute phytotoxicities and genotoxicity of DDE either spiked to soil or added to hydrophonic cultures on wheat Triticum aestivum. A 24-well plate was first used to determine toxicity on individual grains using conventional seed germination/seedling growth toxicity tests whereas a single cell electrophoresis system was applied to measure genotoxicity at single cell level for wheat. Hydrophonic cultures provide a simplified environment to screen for toxicities with high sensitivity. Inverse dose-response relationships were detected between exogenous DDE levels and one of the following parameters: seed germination, seedling growth, and genotoxicity. In contrast, soil reduced the stress on T. aestivum by lowering bioavailability leading to less DDE distributed in radicle and coleoptile, modulated growth, and enhanced tolerance. At all DDE doses spiked to soil including the reference safety level of 0.5 mg/kg, DNA breakage was detected in both radicle and coleoptile but their magnitudes did not correlate with the organ nor the soil DDE contents. Thus, although wheat is highly sensitive to the genotoxic effect of DDE, first demonstrated here, the seed germination test offers a simple quantitative measure of DDE's phytotoxicity in soil and hydrophonic cultures. This study also found that fungus Pleurotus pulmonarius, which secretes extracellular ligninolytic enzymes causing non-specific cleavage of lignin and organopollutants, remediated DDE spiked to soil. In 5 weeks, 78% of 10 mg/kg DDE was biodegraded, and the fungal-treated soil reduced acute toxicity on T. aestivum using the seed germination test. 相似文献
8.
9.
Willard B. Elliott 《Preparative biochemistry & biotechnology》2013,43(1):108-109
The optimal culture conditions of exopolysaccharides (EPS) production in submerged culture medium by Pleurotus geesteranus 5 # were determined using an orthogonal matrix method. The optimal defined medium (per liter) was 60.0 g maltose, 5.0 g tryptone, 1 mM NaCl, 5 mM KH2PO4, and initial pH 6.0 at 28 °C. In the optimal culture medium, the maximum EPS production was 16.97 g/L in a shake flask. Two groups of EPSs (designated as Fr-I and Fr-II) were obtained from the culture filtrates by size exclusion chromatography (SEC), and their molecular characteristics were examined by a multiangle laser-light scattering (MALLS) and refractive index (RI) detector system. The approximate weight-average molar masses of the Fr-I and Fr-II of EPS were determined to be 3.263 × 104 and 5.738 × 103 g/mol, respectively. The low values of polydispersity ratio (1.176 and 1.124 for Fr-I and Fr-II, respectively) of EPSs mean that these EPS molecules exist much less dispersed in aqueous solution without forming large aggregates. Furthermore, the experiments in vitro indicated that P. geesteranus 5# EPS exhibit high antitumor and antioxidative effects. 相似文献
10.