初始气体比例对白玉菇常温气调贮藏品质的影响

在分析不同薄膜包装材料对白玉菇自发气调保鲜过程中气体成分影响规律的基础上,筛选出3组白玉菇气调包装的初始气体比例,以充入空气为对照组,考察不同气调包装条件下的白玉菇常温贮藏过程中的生理、生化指标的变化。结果表明:白玉菇对CO2敏感,高浓度CO2会增加白玉菇的褐变程度,当初始气体比例为O20.4%+CO213.0%+N286.6%时,可有效推迟白玉菇呼吸高峰及PPO活性高峰;保持较低的失重率及较高的硬度;包装内形成低O2和高CO2气体组成,可使白玉菇可溶性总糖含量维持在较高水平上。保鲜时间可达7d以上,具有较好的保鲜效果。     

真姬菇液体菌种培养基筛选和摇瓶发酵条件的研究

采用摇瓶培养法对真姬菇液体菌种培养基筛选和发酵条件进行研究。研究表明,真姬菇液体菌种最佳组合培养基为：葡萄糖3g/100mL、玉米淀粉1g/100mL、黄豆粉1.5g/100mL、(NH4)2SO4 0.3g/100mL、KH2PO4 0.2g/100mL、MgSO4·7H2O 0.1g/100mL 和VB1 10mg/L。真姬菇摇瓶发酵最佳条件为：起始pH 值为6.0,500mL 锥形瓶装液量140～150mL,摇床转速180r/min,温度26℃,二级摇瓶发酵时间72h,接种量10%～12%。     

百菌清在真姬菇及培养料中的残留

为评价百菌清在真姬菇培养料中使用后的残留行为和真姬菇中食品安全性,按照国家标准规定的百菌清最大残留量的2000倍量在培养料中施用后采用工厂化栽培,研究了百菌清在真姬菇培养料中的残留动态。样品中的百菌清采用乙腈提取,固相微萃取柱净化,气相色谱-电子捕获检测器检测的分析方法,外标法定量。仪器最小检出限为3.1×10-11g,方法最低检出质量分数为0.06mg/kg,样本添加回收率在87.6%～107.0%。残留试验研究结果表明,在整个培养期间百菌清在培养料中降解较快,残留半衰期为2.6～4.8d,在收获时真姬菇和培养料中均无残留百菌清检出。     

Color,texture and enzyme activities of Hypsizygus marmoreus as affected by heating combined with color protection and hardening

Different pretreatments can affect the quality of Hypsizygus marmoreus (HM). In this study, the effects of thermal treatment or combined with color protection and hardening on color, texture, microstructure, polyphenol oxidase (PPO) and Peroxidase (POD) C-1: Explain the first time? activities, and the volatile components of HM were investigated. The results showed compared with the control group, both heating group (H group) and color protection, hardening and heating (CHH group) significantly enhanced the color difference, and reduced all texture parameters as well as PPO and POD activities. Additionally, in two treatment groups, the structure of HM became loose, the amounts of alcohols, ketones, and aldehydes were changed significantly. Compared with the H group, the color difference and PPO activities in CHH group were significantly decreased, while all texture parameters were increased significantly, the fibers of HM showed regular arrangement. In conclusion, the combination of CHH performed better effects on hardness, chewiness, microstructure, and enzymes activities related to enzymatic browning.     

A novel glycoprotein from mushroom Hypsizygus marmoreus (Peck) Bigelow with growth inhibitory effect against human leukaemic U937 cells

This study was to isolate the anti-leukaemic component from edible mushroom Hypsizygus marmoreus (Peck) Bigelow. Crude protein was extracted from the basidioma, and then purified with DEAE-Sepharose CL-6B ion exchange chromatography followed by Sephacryl S-300 gel filtration. A protein which exerted high growth inhibitory effect on human leukaemic U937 cells and sufficient toxicological safety on normal human white blood cells was isolated and named HM-3A. Electrophoresis showed HM-3A approximately 52 kDa in size. N-terminal analysis found the amino acid sequence ATTQWKTSAA and confirmed HM-3A a novel protein. High-performance anion-exchange column chromatography revealed HM-3A a glycoprotein with galactose as the major monosaccharide. Haemagglutination assay proved it non-lectin. We suggest that HM-3A is worth further investigation for antitumour use.     

不同食用菌菌糠多糖的组分分析与抗氧化活性评价

目的：比较茶树菇、香菇、白玉菇、平菇和蛹虫草菌糠多糖的组成与抗氧化性。方法：通过酶解水提、乙醇沉淀和Sevag法脱蛋白步骤获得5 种菌糠多糖,进一步对其组成和抗氧化性进行分析评价。结果：5 种菌糠多糖均具有不同程度的抗氧化性,其中茶树菇菌糠多糖的氧自由基清除能力（oxygen radical absorbance capacity,ORAC）值和铁离子还原能力（ferric reducing antioxidant power,FRAP）值最佳,分别达到了1 215 μmol Trolox/g和281 μmol Fe2+/g;而白玉菇与平菇的菌糠多糖对2,2’-联氮基双（3-乙基苯并噻唑啉-6-磺酸）二铵盐（2,2’-azinobis（3-ehtylbenzothiazolin-6-sulfnicacid）diammonium salt,ABTS）自由基和1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基清除能力较强。     

真姬菇研究进展

综述真姬菇在生物学特性、营养成分和生物活性物质等方面的研究进展,探讨进一步研究的方向。     

响应面法优化白玉菇多糖的提取工艺

为优化白玉菇多糖的提取工艺,选取提取温度、提取时间以及水料比(m L/g)为因素,进行单因素实验。并在此基础上,通过响应面法建立数学模型,进行数据分析,对白玉菇多糖提取工艺的各因素进行优化及验证。最终确定最佳工艺条件为:提取温度80℃、提取时间4.2 h、水料比(m L/g)35∶1,白玉菇多糖的平均得率为6.41%。      

低压静电场-真空协同保鲜对白玉菇采后品质和抗氧化代谢的影响

本研究以采后白玉菇为对象,将其在温度（3±1）℃、相对湿度80%～85%条件下贮藏于低压静电场（电压150 V、频率1 000 Hz）、真空（压力26～36 kPa）协同保鲜设备中,通过生理生化指标测定以及感官分析,探究白玉菇贮藏期间的品质变化及抗氧化代谢情况。结果表明,低压静电场-真空协同贮藏（LVEF-Vac）组白玉菇的货架期可达14 d,低压静电场贮藏（LVEF）组白玉菇的货架期为12 d,对照（CK）组白玉菇的货架期只有9 d;与CK组相比,低压静电场和低压静电场-真空协同2 种保鲜处理均可明显降低白玉菇呼吸强度,减少水分散失,显著改善其感官品质（P＜0.05）;与CK、LVEF组相比,LVEF-Vac组能够总体显著提高贮藏期间白玉菇抗氧化酶（抗坏血酸过氧化物酶、过氧化物酶、过氧化氢酶、谷胱甘肽还原酶和超氧化物歧化酶）活力,保持较高的抗氧化物质（谷胱甘肽、氧化型谷胱甘肽和抗坏血酸）含量,从而增强白玉菇直接和间接抗氧化系统的抗氧化能力,显著抑制过氧化氢和超氧阴离子自由基以及丙二醛含量的升高（P＜0.05）,降低膜脂过氧化的程度,维持细胞完整性。综上,低压静电场-真空协同保鲜技术能够改善白玉菇的保鲜品质,延缓采后白玉菇的衰老进程。     

燕麦的食用菌液体发酵及其发酵饮料研究

以燕麦乳为培养基,对4 株灵芝菌种和1 株真姬菇菌种进行液体摇床培养,结合发酵过程中的发酵液pH值、胞内多糖含量、胞外多糖产量、菌体生长量及燕麦β- 葡聚糖变化,分析每株菌的发酵特性,并对菌种“灵芝3”的发酵液进行饮料加工。结果表明,4 株灵芝均能在燕麦乳中快速生长,并产生大量胞内多糖和胞外多糖;胞内多糖含量与菌体生长量的变化趋势基本吻合,两者均在培养的第6 天达到最大值,不同菌株的胞外多糖产量分别在第5 天、第6 天、第7 天达到最大值。真姬菇的胞外多糖产量在培养过程中不断下降,胞内多糖含量与菌体生长量没有相关性。燕麦乳不适用于真姬菇多糖的液体发酵,适用于灵芝多糖的发酵生产。在灵芝发酵液中加入1.5g/L 的CMC-Na,即可制成酸甜适口、质地稳定、澄清透明,含103g/L 多糖、1g/L 总酸、 11.6g/L 氨基酸、40g/L可溶性固形物的灵芝发酵饮料。