BACKGROUND & AIMS: :The fruit bodies of Pleurotus species as a class of "Edible Fungal Foods" have been discovered to have definite nutritive and medicinal values. They are a good source of nonstarchy carbohydrates, dietary fiber (that can help in reducing the plasma cholesterol), most of the essential amino acids, minerals and vitamins of B group, and folic acid (necessary to counteract pernicious anaemia) in particular. Considering the essential amino acid index, biological value, in vitro digestibility, nutritional index, and protein score, Pleurotus species fall between high grade vegetables and low grade meats. Fractions of water-soluble polysaccharides are reported to possess antitumor activity. The physiological processes such as changes in water content, respiratory rate, texture, color, and activities of enzymes like proteases and polyphenol oxidases during the after-harvest life are delineated. The problems and prospects of processing the fruit bodies by various methods are discussed. Potentialities for production and consumption of the fruit bodies in different parts of the world are brought out.

背景与目标： : 已发现平菇属一类 “可食用真菌食品” 的子实体具有一定的营养和药用价值。它们是非淀粉碳水化合物，膳食纤维 (可以帮助降低血浆胆固醇)，b群的大多数必需氨基酸，矿物质和维生素以及叶酸 (应对恶性贫血所必需的) 的良好来源。考虑到必需氨基酸指数，生物学价值，体外消化率，营养指数和蛋白质评分，侧耳属属于高档蔬菜和低档肉类。据报道，水溶性多糖的部分具有抗肿瘤活性。描述了生理过程，例如水分含量，呼吸频率，质地，颜色以及收获后生活中蛋白酶和多酚氧化酶等酶的活性的变化。讨论了用各种方法加工子实体的问题和前景。展示了世界不同地区生产和消费子实体的潜力。

BACKGROUND & AIMS: :Pleurotus ostreatus is one of the widely cultivated edible mushrooms. Water-soluble proteoglycan fractions from P. ostreatus mycelia were purified by alcohol-precipitation, ion exchange and followed by gel permeation (Sephadex G-100) chromatography. Three neutral fractions were found, which had polysaccharide to protein ratios 14.2, 26.4 and 18.3, respectively. These fractions were tested for in vitro and in vivo immunomodulatory and anticancer effects on Sarcoma-180-bearing mouse model. In vivo injection of proteoglycans to Sarcoma-180-bearing mice decreased the number of tumor cells and cell cycle analysis showed that most of the cells were found to be arrested in pre-G(0)/G(1) phase of cell cycle. All of the three proteoglycans elevated mouse natural killer (NK) cell cytotoxicity and stimulated macrophages to produce nitric oxide. The Fourier transform infra red (FTIR) spectra suggested the presence of beta-glycosidic bond in all the fractions. Fraction I strongly interacted with glucose/mannose-specific lectin Concanavalin A (ConA), indicating the presence of large number of terminal sugar with glucose/mannose. Thus, the three neutral proteoglycans derived from the mushroom (P. ostreatus) mycelia could be used as immunomodulators and anti cancer agents.

背景与目标： : 平菇是广泛栽培的食用菌之一。通过醇沉淀，离子交换和随后的凝胶渗透 (Sephadex G-100) 色谱法纯化来自P. ostreatus菌丝体的水溶性蛋白聚糖组分。发现了三个中性部分，其多糖与蛋白质的比例分别为14.2、26.4和18.3。测试这些级分对肉瘤180小鼠模型的体外和体内免疫调节和抗癌作用。向荷肉瘤180的小鼠体内注射蛋白聚糖减少了肿瘤细胞的数量，细胞周期分析表明，发现大多数细胞在细胞周期的前G(0)/G(1) 阶段被阻滞。三种蛋白聚糖均提高了小鼠自然杀伤 (NK) 细胞的细胞毒性，并刺激巨噬细胞产生一氧化氮。傅里叶变换红外 (FTIR) 光谱表明所有馏分中都存在 β-糖苷键。馏分I与葡萄糖/甘露糖特异性凝集素伴刀豆球蛋白A (ConA) 强烈相互作用，表明存在大量葡萄糖/甘露糖末端糖。因此，来自蘑菇 (P. ostreatus) 菌丝体的三种中性蛋白聚糖可以用作免疫调节剂和抗癌剂。

BACKGROUND & AIMS: :The novelty of the present work looks in the synthesis of aqueous dispersed selenium nanoparticles (Se NPs) using gamma rays with the aid of various natural macromolecules such as citrus pectin (CP), sodium alginate (Alg), chitosan (CS) and aqueous extract of fermented fenugreek powder (AEFFP) using Pleurotus ostreatus for investigating their impact in vitro toward carcinoma cell. The synthesized Se NPs were characterized by XRD, UV-Vis., DLS, HRTEM, SEM, EDX and FTIR. Nucleation and growth mechanisms were also discussed. The factorial design was applied to examine the importance of multiple parameters on Se NPs production with a special focus on temperature and gamma rays influences. FTIR spectrum exhibited the existence of several functional groups in Se NPs-capping macromolecules. Results revealed that Se NPs' size was dramatically-influenced by the type of stabilizer, precursors concentration, pH and the absorbed gamma rays dose. The current research reported the promising antitumor application of Se NPs against Ehrlich Ascites Carcinoma (EAC) and human Colon Adenocarcinoma (CACO) in vitro. The proliferation of EAC was significantly-hindered by Se NPs-CS (38.0 μg/ml) at 60 kGy (IC50 = 23.12%) and Se NPs-AEFFP (19.00 μg/ml) at 15 kGy (IC50 = 7.21%). Also, Se NPs control the generation of CACO cells, IC50 was recorded as 25.32% for Se NPs-CS (38.0 μg/ml) and 8.57% for Se NPs-AEFFP (19.00 μg/ml).

背景与目标： : 本工作的新颖之处在于使用 γ射线在各种天然大分子 (例如柑橘果胶 (CP)，海藻酸钠 (Alg)) 的帮助下合成水性分散的硒纳米颗粒 (Se NPs)，壳聚糖 (CS) 和发酵胡芦巴粉 (AEFFP) 的水提取物使用平菇研究其对癌细胞的体外影响。通过XRD，UV-Vis，DLS，HRTEM，SEM，EDX和FTIR对合成的Se NPs进行了表征。还讨论了成核和生长机理。析因设计用于检查多个参数对Se NPs生产的重要性，特别关注温度和伽马射线的影响。FTIR光谱显示Se NPs封端大分子中存在几个官能团。结果表明，Se np的大小受稳定剂类型，前体浓度，pH和吸收的伽马射线剂量的影响很大。目前的研究报道了Se NPs在体外对艾氏腹水癌 (EAC) 和人结肠腺癌 (CACO) 的抗肿瘤应用前景。60 kGy (IC50 = 23.12%) 的Se NPs-CS (38.0 μ g/ml) 和15 kGy (IC50 = 7.21%) 的Se NPs-AEFFP (19.00 μ g/ml) 显着阻碍了EAC的增殖。此外，Se NPs控制CACO细胞的产生，IC50被记录为Se nps-cs (38.0 μ g/ml) 的25.32% 和Se nps-aeffp (19.00 μ g/ml) 的8.57%。

BACKGROUND & AIMS: :Blue light is an important environmental factor that induces mushroom primordium differentiation and fruiting body development. Although blue-light treatment has been applied for the production of oyster mushroom (Pleurotus ostreatus), the blue-light response mechanisms of P. ostreatus still remain unclear. In the present study, we exposed the primordium of P. ostreatus to blue-light, red-light, and dark conditions for 7 days. Subsequently, comparative transcriptomics analysis of the stipe, pileus, and gill under the three light conditions was performed to reveal the gene expression response mechanism of P. ostreatus to blue light and red light. The results showed that blue light enhanced the growth and development of all the three organs of P. ostreatus, especially the pileus. In contrast, red light slightly (non-significantly) inhibited pileus growth. When compared with red-light and dark treatments, blue-light treatment significantly upregulated gene expression involved in glycolysis/gluconeogenesis, the pentose phosphate pathway and the peroxisome in the pileus, but not in the gill or stipe. Most of the glycolysis and pentose phosphate pathway genes were upregulated in the pileus by blue light. When compared with dark treatment, red-light treatment downregulated the expression of many respiration metabolism genes in the pileus. These results revealed that blue light enhanced the activation of glycolysis and the pentose phosphate pathway, whereas red light weakened glycolysis and pentose phosphate pathway activation. The conclusion can be drawn that blue light improved P. ostreatus fruiting body (particularly, the pileus) growth rate via enhancement of glycolysis and the pentose phosphate pathway.

背景与目标： : 蓝光是诱导蘑菇原基分化和子实体发育的重要环境因素。尽管已将蓝光处理应用于牡蛎蘑菇 (平菇) 的生产，但对平菇的蓝光反应机制仍不清楚。在本研究中，我们将P. ostreatus的原基暴露于蓝光，红光和黑暗条件下7天。随后，对三种光照条件下的菌柄、菌体和鳃进行了比较转录组学分析，以揭示平菇对蓝光和红光的基因表达反应机制。结果表明，蓝光促进了P的所有三个器官的生长和发育。ostreatus，尤其是pileus。相反，红光略微 (非显着) 抑制了堆积的生长。与红光和暗处理相比，蓝光处理显着上调了与糖酵解/糖异生，戊糖磷酸途径和过氧化物酶体有关的基因表达，但在the或柄中却没有。大多数糖酵解和磷酸戊糖途径基因在蓝光中被上调。与暗处理相比，红光处理下调了pileus中许多呼吸代谢基因的表达。这些结果表明，蓝光增强了糖酵解和戊糖磷酸途径的激活，而红光减弱了糖酵解和戊糖磷酸途径的激活。可以得出结论，蓝光通过增强糖酵解和磷酸戊糖途径提高了P. ostreatus子实体 (尤其是pileus) 的生长速率。

BACKGROUND & AIMS: :Pleurotus ostreatus is a widely cultivated edible fungus around the world. At present, studies on the developmental process of the fruiting body are limited. In our study, we compared the differentially expressed proteins (DEPs) in the stipe and cap of the fruiting body by high-throughput proteomics. GO and pathway analysis revealed the great differences in the metabolic levels, including sucrose and starch metabolism, and sphingolipid signaling and metabolism, and the differences of 16 important DEPs were validated further by qPCR analysis in expression level. In order to control the cap and stipe development, several chemical inducers were applied to the primordium of the fruiting body according to the pathway enrichment results. We found that CaCl2 can affect the primordium differentiation through inhibiting the stipe development. EGTA (ethyleneglycol bis (β-aminoethyl ether)-N,N,N',N'-tetraacetic acid) treatment confirmed the inhibitory role of Ca2+ in the stipe development. Our study not only shows great metabolic differences during the cap and stipe development but also reveals the underlying mechanism directing the primordium differentiation in the early development of the fruiting body for the first time. Most importantly, we provide a reliable application strategy for the cultivation and improvement of the Pleurotus ostreatus, which can be an example and reference for a more edible fungus.

背景与目标： : 平菇是世界各地广泛栽培的食用菌。目前，对子实体发育过程的研究有限。在我们的研究中，我们通过高通量蛋白质组学比较了子实体的菌柄和菌盖中的差异表达蛋白 (DEPs)。GO和pathway分析显示了代谢水平的差异，包括蔗糖和淀粉代谢以及鞘脂信号和代谢，并且通过qPCR分析进一步验证了16个重要dep的表达水平差异。为了控制菌盖和菌柄的发育，根据途径富集结果，将几种化学诱导剂应用于子实体的原基。我们发现CaCl2可以通过抑制柄的发育来影响原基的分化。EGTA (乙二醇双 (β-氨基乙基醚)-N，N，N'，N'-四乙酸) 处理证实了Ca2在柄发育中的抑制作用。我们的研究不仅显示了帽和柄发育过程中的巨大代谢差异，而且首次揭示了指导子实体早期发育中基原分化的潜在机制。最重要的是，我们为平菇的栽培和改良提供了可靠的应用策略，可以为更多的食用菌提供示例和参考。

BACKGROUND & AIMS: OBJECTIVES:To study the antidiabetic activity of Pleurotus ostreatus in normal and alloxan-induced diabetic mice. MATERIALS AND METHODS:Ethanolic extract of fruiting bodies of P. ostreatus was tested for their antidiabetic activity. BALB/C mice (25-30 g) were divided into four groups of six animals each normal control mice, diabetic control mice, diabetic mice posttreated with standard drug glibenclamide and diabetic mice treated with P. ostreatus ethanolic extract. Blood glucose level, biochemical parameters such as serum total cholesterol, LDL, HDL, VLDL, triglyceride creatinine, urea, and Serum glutamate oxaloacetate transaminase and Serum glutamate pyruvate transaminase were studied in alloxan-induced diabetic mice after 15 days of treatment. RESULTS:Animals treated with the ethanolic extract of P. ostreatus showed a significant decrease in serum glucose level (p < 0.01). The posttreatment with P. ostreatus extract reduced serum cholesterol, triglyceride and LDL-cholesterol. The serum HDL cholesterol was significantly increased in posttreated groups. The serum creatinine, urea levels were significantly reduced in posttreated group, whereas the decrease in the body weight was arrested by administration of P. ostreatus extract to the animals. DISCUSSION AND CONCLUSION:The consumption of P. ostreatus produced a significant hypoglycemic effect in diabetic mice and it is capable of improving hyperlipidemia and the impaired kidney functions in alloxan-induced diabetic mice. Thus, indicating that the ethanolic extract of P. ostreatus could be added in the list of medicinal preparations beneficial in diabetes mellitus.

背景与目标：

BACKGROUND & AIMS: :A novel mycovirus was isolated from a cultivated edible mushroom, Pleurotus eryngii, with severe epidemic symptoms. Purification of the virus was carried out by a sequential procedure of polyethylene glycol precipitation, differential centrifugation, and equilibrium centrifugation in a CsCl gradient. Nuclease digestion assay and protein analysis revealed that the virus consisted of a single-stranded RNA (ssRNA) genome of 7.8 kbp which was encapsulated by a coat protein of 22 kDa. Transmission electron microscope showed that it was spherical with a diameter of 31 nm. Since there was neither a previous report on discovery of a virus in P. eryngii, nor known mushroom viruses with similar characteristics, we concluded that this is a novel virus and thus have named it as P. e ryngii Spherical Virus (PeSV). Because of a diagnostic test would be helpful in preventing the PeSV-related disease outbreaks, we developed a triple antibody sandwich-ELISA (TAS-ELISA) system using anti-PeSV mouse monoclonal and anti-PeSV rabbit polyclonal antibodies. The TAS-ELISA system successfully detected less than 0.5 microg of the virus particles in 1 g diseased mushroom tissue collected from various commercial farms.

背景与目标： : 从栽培的食用蘑菇杏鲍菇中分离出一种新型分枝杆菌，具有严重的流行症状。病毒的纯化是通过在CsCl梯度中进行的聚乙二醇沉淀，差速离心和平衡离心的顺序程序进行的。核酸酶消化试验和蛋白质分析表明，该病毒由7.8 kbp的单链RNA (ssRNA) 基因组组成，该基因组被22 kDa的外壳蛋白包裹。透射电子显微镜显示它是球形的，直径为31 nm。由于以前没有关于在杏鲍菇中发现病毒的报道，也没有已知具有类似特征的蘑菇病毒，因此我们得出结论，这是一种新型病毒，因此将其命名为杏鲍菇球形病毒 (PeSV)。由于诊断测试有助于预防PeSV相关疾病的爆发，因此我们开发了使用抗PeSV小鼠单克隆和抗PeSV兔多克隆抗体的三重抗体夹心ELISA (TAS-ELISA) 系统。TAS-ELISA系统成功地检测到从各种商业农场收集的1 g患病蘑菇组织中少于0.5微克的病毒颗粒。

BACKGROUND & AIMS: :The wide industrial cultivation of Pleurotus eryngii (P. eryngii) has resulted in the massive production of mushroom residues (MR) with low-efficiency utilization. In the present study, the P. eryngii enzymatic residue polysaccharide (PERP) was obtained from the P. eryngii residues. The characterization analysis showed that PERP was polysaccharides comprised of five kinds of monosaccharides with molecular weight of 2.05 × 103 Da. PERP also showed rough surface and appeared as spherical structure dispersed in aqueous solution. The animal experiment analysis demonstrated that PERP exhibited potential anti-ageing effects on the brain, liver, kidney and skin, possibly by scavenging reactive radicals, improving the antioxidant status, supressing lipid peroxidation, enhancing organ functions and ameliorating histopathological damage. These results may provide a reference for the efficient utilization of P. eryngii residues in exploring MR-derived functional foods or drugs that delay the ageing process.

背景与目标： : 杏鲍菇 (P. eryngii) 的广泛工业种植导致了低效率利用的蘑菇残渣 (MR) 的大量生产。在本研究中，从P. eryngii残基中获得了P. eryngii酶促残基多糖 (PERP)。表征分析表明，PERP是由5种单糖组成的多糖，分子量为2.05 × 103 Da。PERP还显示出粗糙的表面，并以分散在水溶液中的球形结构出现。动物实验分析表明，PERP可能通过清除反应性自由基，改善抗氧化状态，抑制脂质过氧化，增强器官功能，改善组织病理学损伤，对脑、肝、肾和皮肤具有潜在的抗衰老作用。这些结果可为有效利用eryngii残留探索MR衍生的功能性食品或延缓衰老过程的药物提供参考。

BACKGROUND & AIMS: :A new extracellular protease (PoSl; Pleurotus ostreatus subtilisin-like protease) from P. ostreatus culture broth has been purified and characterized. PoSl is a monomeric glycoprotein with a molecular mass of 75 kDa, a pI of 4.5, and an optimum pH in the alkaline range. The inhibitory profile indicates that PoSl is a serine protease. The N-terminal and three tryptic peptide sequences of PoSl have been determined. The homology of one internal peptide with conserved sequence around the Asp residue of the catalytic triad in the subtilase family suggests that PoSl is a subtilisin-like protease. This hypothesis is further supported by the finding that PoSl hydrolysis sites of the insulin B chain match those of subtilisin. PoSl activity is positively affected by calcium. A 10-fold decrease in the K(m) value in the presence of calcium ions can reflect an induced structural change in the substrate recognition site region. Furthermore, Ca(2+) binding slows PoSl autolysis, triggering the protein to form a more compact structure. These effects have already been observed for subtilisin and other serine proteases. Moreover, PoSl protease seems to play a key role in the regulation of P. ostreatus laccase activity by degrading and/or activating different isoenzymes.

背景与目标： : 已纯化并鉴定了来自P. ostreatus培养液的一种新的细胞外蛋白酶 (PoSl; 平菇枯草蛋白酶样蛋白酶)。PoSl是一种单体糖蛋白，分子量为75 kDa，pI为4.5，在碱性范围内的最佳pH。抑制特性表明PoSl是丝氨酸蛋白酶。已确定PoSl的N端和三个胰蛋白酶肽序列。在枯草杆菌酶家族中催化三联体的Asp残基周围具有保守的序列的一种内部肽的同源性表明，PoSl是一种枯草杆菌蛋白酶样蛋白酶。胰岛素B链的PoSl水解位点与枯草杆菌蛋白酶的水解位点相匹配的发现进一步支持了这一假设。PoSl活性受钙的正向影响。在钙离子存在下，K(m) 值降低10倍可以反映出诱导的底物识别位点区域的结构变化。此外，Ca(2) 结合会减慢PoSl自溶，从而触发蛋白质形成更紧凑的结构。枯草杆菌蛋白酶和其他丝氨酸蛋白酶已经观察到这些作用。此外，PoSl蛋白酶似乎通过降解和/或激活不同的同工酶在调节P. ostreatus漆酶活性中起关键作用。

BACKGROUND & AIMS: :Mushroom cultivation has been started recently in Bangladesh. Awareness of the nutritional and medicinal importance of mushrooms is not extensive. In this study, the nutritional values of dietary mushrooms- Pleurotus ostreatus, Pleurotus sajorcaju, Pleurotus florida and Calocybe indica that are very popular among the cultivated mushrooms in Bangladesh have been determined. These mushrooms were rich in proteins (20~25%) and fibers (13~24% in dry samples) and contained a lower amount of lipid (4 to 5%). The carbohydrate contents ranged from 37 to 48% (on the basis of dry weight). These were also rich in mineral contents (total ash content is 8~13%). The pileus and gills were protein and lipid rich and stripe was carbohydrate and fiber-rich. The moisture content of mushrooms ranged from 86 to 87.5%. Data of this study suggest that mushrooms are rich in nutritional value.

背景与目标： : 孟加拉国最近开始种植蘑菇。对蘑菇的营养和药用重要性的认识并不广泛。在这项研究中，已经确定了在孟加拉国栽培蘑菇中非常受欢迎的饮食蘑菇-平菇，平菇，佛罗里达平菇和indica的营养价值。这些蘑菇富含蛋白质 (20〜25%) 和纤维 (干燥样品中的13〜24%)，并且含有较低量的脂质 (4〜5%)。碳水化合物含量为37至48% (基于干重)。这些矿物含量也很丰富 (总灰分为8 ~ 13%)。pileus和g富含蛋白质和脂质，条纹富含碳水化合物和纤维。蘑菇的水分含量范围为86至87.5%。这项研究的数据表明，蘑菇具有丰富的营养价值。

BACKGROUND & AIMS: :Eight distinct bacteria were isolated form diseased mycelia of the edible mushroom, Pleurotus eryngii. 16S rDNA sequence analysis showed that the isolates belonged to a variety of bacterial genera including Bacillus (LBS5), Enterobacter (LBS1), Sphingomonas (LBS8 and LBS10), Staphylococcus (LBS3, LBS4 and LBS9) and Moraxella (LBS6). Among them, 4 bacterial isolates including LBS1, LBS4, LBS5, and LBS9 evidenced growth inhibitory activity on the mushroom mycelia. The inhibitory activity on the growth of the mushroom fruiting bodies was evaluated by the treatment of the bacterial culture broth or the heat-treated cell-free supernatant of the broth. The treatment of the culture broths or the cell-free supernatants of LBS4 or LBS9 completely inhibited the formation of the fruiting body, thereby suggesting that the inhibitory agent is a heat-stable compound. In the case of LBS5, only the bacterial cell-containing culture broth was capable of inhibiting the formation of the fruiting body, whereas the cell-free supernatant did not, which suggests that an inhibitory agent generated by LBS5 is a protein or a heat-labile chemical compound, potentially a fungal cell wall-degrading enzyme. The culture broth of LBS1 was not inhibitory. However, its cell-free supernatant was capable of inhibiting the formation of fruiting bodies. This indicates that LBS1 may produce an inhibitory heat-stable chemical compound which is readily degraded by its own secreted enzyme.

背景与目标： : 从食用菌杏鲍菇的患病菌丝体中分离出八种不同的细菌。16S rDNA序列分析表明，分离株属于多种细菌属，包括芽孢杆菌 (LBS5)，肠杆菌 (LBS1)，鞘氨醇单胞菌 (LBS8和LBS10)，葡萄球菌 (LBS3，LBS4和LBS9) 和莫拉菌 (LBS6)。其中，包括LBS1，LBS4，LBS5和LBS9在内的4种细菌分离株对蘑菇菌丝体的生长抑制活性。通过处理细菌培养液或热处理的培养液的无细胞上清液来评估对蘑菇子实体生长的抑制活性。LBS4或LBS9的培养液或无细胞上清液的处理完全抑制了子实体的形成，从而表明抑制剂是热稳定的化合物。在LBS5的情况下，只有含细菌细胞的培养液能够抑制子实体的形成，而无细胞上清液则不能，这表明LBS5产生的抑制剂是蛋白质或热不稳定的化学化合物，潜在的真菌细胞壁降解酶。LBS1的培养液没有抑制作用。然而，其无细胞上清液能够抑制子实体的形成。这表明LBS1可能会产生抑制性热稳定的化合物，该化合物很容易被其自身分泌的酶降解。

BACKGROUND & AIMS: :A full length cDNA encoding an extracellular laccase was isolated by reverse transcription polymerase chain reaction from the mycelia of the mushroom Pleurotus eryngii. The isolated sequence, denoted Ery3, encodes for a mature laccase isoenzyme of 531 amino acid residues with a predicted molecular weight of 56.6 kDa. All sequence motifs, being the signature sequences used to identify the laccases, were found in the Ery3 protein sequence. The Ery3 cDNA was expressed in Saccharomyces cerevisiae and the effects of copper concentration and cultivation temperature were investigated. S. cerevisiae cells were immobilized in calcium alginate gel and the optimal immobilization parameters for the enhanced production of laccase were determined. The immobilization was most effective with 3% sodium alginate, 0.1 M calcium chloride and an initial biomass of 4.5 x 10(8) cells. The enzyme yield obtained with immobilized cells (139 mU ml(-1)) showed a 1.6-fold increase compared to the highest yield obtained with free cells. The alginate beads showed good stability and retained 84% capacity of enzyme production after seven repeated cycles of batch fermentation. The immobilization system proved to increase the proteolytic stability of the recombinant Ery3 protein. To our knowledge, this is the first report on S. cerevisiae whole-cell immobilization for recombinant laccase production.

背景与目标： : 通过逆转录聚合酶链反应从蘑菇杏鲍菇的菌丝体中分离出编码细胞外漆酶的全长cDNA。表示为Ery3的分离序列编码预测分子量为56.6 kDa的531个氨基酸残基的成熟漆酶同工酶。在Ery3蛋白序列中发现了所有序列基序，即用于鉴定漆酶的特征序列。Ery3 cDNA在酿酒酵母中表达，并研究了铜浓度和培养温度的影响。将酿酒酵母细胞固定在藻酸钙凝胶中，并确定了提高漆酶产量的最佳固定化参数。用3% 海藻酸钠，0.1 M氯化钙和4.5 × 10(8) 细胞的初始生物量固定最有效。与用游离细胞获得的最高产量相比，用固定化细胞 (139 μ ml(-1)) 获得的酶产量增加了1.6倍。经过7个重复循环的分批发酵，藻酸盐珠显示出良好的稳定性和保持84% 的产酶能力。固定化系统被证明可以提高重组Ery3蛋白的蛋白水解稳定性。据我们所知，这是关于酿酒酵母全细胞固定用于重组漆酶生产的第一份报告。

BACKGROUND & AIMS: :Mycelial growth and laccase production by Pleurotus ostreatus CP50 cultured in a 10-L mechanically agitated bioreactor were assessed through a 2(3) factorial experimental design. The main effects and interactions of three factors (agitation, aeration and copper induction) over five responses (μ, αLacc, βLacc, maximal volumetric laccase activity and maximal biomass concentration) were analyzed. P. ostreatus growth was significantly improved when culturing was conducted with high agitation (5.9kW/m(3)s) and aeration flow (0.5vvm) rates. Under the experimental conditions evaluated, no evidence of hydrodynamic stress affecting fungal growth was observed. However, the high agitation and aeration conditions were detrimental for the growth-associated laccase production constant (αLacc), leading to a very complex optimization of the process. The maximal laccase volumetric activity (1.2 and 3.8U/ml for non-induced and copper-induced cultures, respectively) was observed when the culturing was performed at a low agitation rate (0.9kW/m(3)s) and a high aeration flow rate (0.5vvm). Laccase proteolysis may explain the complex interactions observed between agitation and aeration and the effects of these factors on the laccase volumetric activity observed in the cultures.

背景与目标： : 通过2(3) 析因实验设计评估了在10升机械搅拌生物反应器中培养的平菇CP50的菌丝生长和漆酶产生。分析了三个因素 (搅拌，曝气和铜诱导) 在五个响应 (μ，α lacc，β lacc，最大体积漆酶活性和最大生物量浓度) 上的主要作用和相互作用。当以高搅拌 (5.9kW/m(3)s) 和曝气流量 (0.5vvm) 进行培养时，P. ostreatus的生长显着改善。在评估的实验条件下，没有观察到水动力应力影响真菌生长的证据。然而，高搅拌和曝气条件不利于与生长相关的漆酶生产常数 (α lacc)，从而导致工艺的非常复杂的优化。当在低搅拌速率 (0.9kW/m(3)s) 和高曝气流速 (0.5vvm) 下进行培养时，观察到最大漆酶体积活性 (对于非诱导和铜诱导培养分别为1.2和3.8U/ml)。漆酶蛋白水解可以解释在搅拌和曝气之间观察到的复杂相互作用以及这些因素对培养物中观察到的漆酶体积活性的影响。

BACKGROUND & AIMS: The properties of the haem environment of an extracellular peroxidase from Pleurotus ostreatus were studied by electronic absorption spectroscopy. A high-spin ferric form was predominant in the native enzyme and a high-spin ferrous form in the reduced enzyme. Cyanide was readily bound to the haem iron in the native form, thereby changing the enzyme to a low-spin cyano adduct. The electronic absorption spectra of the enzyme were similar to those of lignin peroxidase from Phanerochaete chrysosporium. Compound III of the enzyme was formed after the addition of an excess of H2O2 to the native enzyme, and thereafter spontaneously reverted to the native form. The enzyme oxidized 1-(3,5-dimethoxy-4-hydroxyphenyl)-2-(2-methoxyphenoxy)-1,3-dihydroxyp ropane in the presence of H2O2 to produce 1-(3,5-dimethoxy-4-hydroxyphenyl)-2-(2-methoxyphenoxy)-1-oxo-3-hydroxypr opane , 2,6-dimethoxyhydroquinone, 2-(2-methoxyphenoxy)-3-hydroxypropanal, 2-(2-methoxyphenoxy)-3-hydroxypropanoic acid, 2,6-dimethoxy-1,4-benzoquinone and guaiacol. A similar oxidation pattern was demonstrated with a one-electron oxidant, ammonium cerium(IV)nitrate. Free radicals were detected as intermediates of the enzyme-mediated oxidation of 1-(3,5-dimethoxy-5-hydroxyphenyl)-2-(2-methoxyphenoxy)-1,3-dihydroxyp ropane and acetosyringone. These results can be explained by the mechanisms involving an initial one-electron oxidation of the lignin substructure. This radical may undergo C alpha-C beta cleavage, C alpha-oxidation and alkyl-phenyl cleavage.

背景与目标： 通过电子吸收光谱法研究了平菇胞外过氧化物酶的血红素环境的性质。高自旋铁形式在天然酶中占主导地位，而在还原酶中占主导地位。氰化物很容易以天然形式与血红素铁结合，从而将酶转变为低旋氰基加合物。该酶的电子吸收光谱与来自黄孢Phanerochaete的木质素过氧化物酶的电子吸收光谱相似。在向天然酶中添加过量的H2O2后形成酶的化合物III，然后自发地恢复为天然形式。该酶在H2O2存在下氧化1-(3,5-二甲氧基-4-羟基苯基)-2-(2-甲氧基苯氧基)-1,3-二羟基p罗烷，生成1-(3,5-二甲氧基-4-羟基苯基)-2-(2-甲氧基苯氧基)-1-氧代-3-羟基吡喃，2,6-二甲氧基氢醌，2-(2-甲氧基苯氧基)-3-羟基丙醛，2-(2-甲氧基苯氧基)-3-羟基丙酸，2,6-二甲氧基-1,4-苯醌和愈创木酚。用单电子氧化剂硝酸铈 (IV) 铵证明了类似的氧化模式。自由基被检测为酶介导的1-(3,5-二甲氧基-5-羟基苯基)-2-(2-甲氧基苯氧基)-1,3-二羟基丙烷和乙酰丁香酮氧化的中间体。这些结果可以通过涉及木质素亚结构的初始单电子氧化的机理来解释。该自由基可能会发生C α-C β 裂解，C α 氧化和烷基苯基裂解。

BACKGROUND & AIMS: :This study investigated the biochemical changes of abnormal fruiting bodies grown under artificial environmental conditions in P. ostreatus. Abnormal mushroom growth during cultivation damages the production of good quality mushroom. This study showed that different environmental conditions produced morphological changes in the fruiting bodies of P. ostreatus. The fruiting bodies with morphological changes were collected and examined for differences in biochemical properties, enzyme activities, and carbohydrates composition. The enzyme activities assay showed that glucanase and chitinase activities decreased when the temperature was below or above the optimum cultivation temperature for P. ostreatus. The biochemical compositions of the abnormal mushroom were significantly different from the normal fruiting bodies. It was suggested that the changes in the biochemical composition of abnormal mushroom were caused by the unfavorable environmental conditions during mushroom cultivation.

背景与目标： : 本研究调查了在人工环境条件下生长的异常子实体的生化变化。栽培过程中异常的蘑菇生长会损害优质蘑菇的生产。这项研究表明，不同的环境条件在P. ostreatus子实体中产生了形态变化。收集具有形态变化的子实体，并检查其生化特性，酶活性和碳水化合物组成的差异。酶活性测定表明，当温度低于或高于P.Streatus的最佳培养温度时，葡聚糖酶和几丁质酶的活性降低。异常蘑菇的生化成分与正常子实体显着不同。提示异常蘑菇生化成分的变化是由蘑菇栽培过程中不利的环境条件引起的。