阿魏菇菌糠提取液对四种食用菌菌丝生长的影响

目的:解决菌糠再利用技术问题.方法:采用平板培养法,对在PDA培养基中加入不同体积比的阿魏菇菌糠提取液对鸡腿菇、香菇、杏鲍菇和金针菇菌丝生长的影响进行了研究.结果:当PDA培养基中菌糠提取液加入量为10%～50%时,对香菇和金针菇菌丝生长有促进或明显促进作用;而加入量为10%的菌糠提取液对杏鲍菇菌丝生长无显著影响,但当阿魏菇菌糠提取液加入量大于10%时,明显抑制杏鲍菇和鸡腿菇的菌丝生长.结论:可利用阿魏菇菌糠作为栽培香菇和金针菇的培养料.     

蛹虫草及金针菇菌糠对杏鲍菇菌丝生长的影响

通过测定菌丝生长速度及麦角甾醇含量对蛹虫草及金针菇菌糠培养杏鲍菇的效果进行评价。结果表明:大米类和小麦类蛹虫草菌糠总氮含量分别为2.15%和1.90%。小麦类菌糠比大米类更利于杏鲍菇菌丝的生长,添加量为10%时,杏鲍菇菌丝生长速度为3.8 mm/d,其次是添加量为20%的大米类菌糠,为3.6 mm/d。这两组培养基中杏鲍菇菌丝含麦角甾醇最高,分别为0.30μg/g和0.23μg/g。蛹虫草菌糠可作为补充氮源用于金针菇菌糠培养杏鲍菇。     

刺芹侧耳菌渣对肺形侧耳（秀珍菇）生长和营养成分的影响

以常规棉籽壳培养料为对照,用刺芹侧耳Pleurotus eryngii工厂化生产的废料（简称菌渣）代替部分棉籽壳进行格氏侧耳Pleurotus geesterani栽培试验,并测定格氏侧耳的营养成分。结果表明,供试培养料中菌丝长势均良好,随着菌渣替代比例的增加,菌丝满袋时间、原基出现时间和转潮期缩短,生长周期变短;菌渣代替比例增加,产量呈降低趋势,其中替代比例33%（1:2）和55%（1.2:1）时培养料的生物学效率与对照无显著差异,替代比例55%和78%（3.5:1）时培养料对第四潮和第五潮菇产量影响明显,显著低于对照;供试菌渣培养料栽培格氏侧耳的粗蛋白和总氨基酸含量略高于或显著高于对照,说明添加适量的菌渣栽培格氏侧耳可提高子实体的营养成分。     

香菇栽培料新工艺

在国内香菇栽培料常规配方基础上,设计了添加2.5mL盐酸/kg取代常规配方中1%蔗糖的新工艺,经测定,2种栽培料灭菌后还原糖与蔗糖浓度、发菌期与子实体产量基本一致,新配方栽培料灭菌后pH值为5.6,是香菇菌丝生长最适pH值。新配方工艺可降低生产成本10%左右。     

在哈尔滨地区使用液体菌种栽培红平菇技术初探

从福建三明真菌研究所(福建省三明市375000)购入红平菇优良菌株,在哈尔滨地区对其进行了用液体菌种代替固体原料的栽培技术研究。包括一级种培养基的筛选、液体菌种培养基的筛选、栽培种制作与培养以及出菇管理技术。结果表明:对于一级种,红平菇在PDA和马铃薯半组合培养基上都生长良好,菌丝洁白、粗壮、浓密,7～8d长满斜面;红平菇在玉米粉葡萄糖蛋白胨和麦麸葡萄糖蛋白胨液体培养基上生长较好,7d时菌丝长满培养液,菌丝量较多;用与平菇相似的常规方法制作栽培种、养菌处理与出菇管理,红平菇的产量达100%～150%。由于采用了液体菌种的栽培模式,从制种到采收的整个过程共需要50～60d,比二级种为固体菌种的常规方法缩短26～31d,大大地缩短了生产周期,提高了经济效益。     

卵孢小奥德蘑驯化栽培、营养成分及抗氧化活性

卵孢小奥德蘑是一种珍贵的食药用真菌。本研究选用果渣、酒糟与菌糠为部分替代料,采用正交试验优化了野生卵孢小奥德蘑的母种、原种及栽培料配方,并测定了栽培子实体的含水量、蛋白质、总糖、维生素C、多酚含量及醇提物对DPPH、ABTs⁺及羟基自由基的清除能力。结果表明,最佳母种培养基配方为麦麸35 g/L、葡萄糖20 g/L、磷酸氢二钾3.5 g/L、硫酸镁2 g/L和琼脂20 g/L,确定了葡萄糖与磷酸氢二钾是影响菌丝生长的重要因素;最优原种培养基配方为果渣45%、豆秸20%、麦麸15%、石灰3%、石膏1%和刺芹侧耳菌糠16%,在培养基中添加果渣能够显著促进卵孢小奥德蘑原种菌丝的生长;最佳栽培料配方为酒糟35%、棉籽壳30%、麦麸20%、石灰1%、石膏1%和玉米芯13%,酒糟对子实体产量的影响达到了显著水平;卵孢小奥德蘑的营养成分显示其富含蛋白质、糖类、维生素C及多酚,由9种配方栽培出的子实体中最高含量可分别达到42.78 g/100 g、23.54 g/100 g、4.02 mg/100 g及4.19 mg/g,且栽培料的不同组分及用量对其营养物质的含量具有显著差异。此外,卵孢小奥德蘑的醇提物具有较强的抗氧化能力且随着用量的增加抗氧化活性增强,当用量为150、40和250 μL时配方Z1对DPPH和ABTs⁺及配方Z2对羟基自由基的清除能力可分别达到88.64%、99.81%和93.48%,本研究结果为卵孢小奥德蘑的栽培、生理活性、药理研究及进一步的开发利用提供理论依据。     

银合欢叶对食用菌菌丝生长的效应及菌丝对含羞草素的降解作用

银合欢叶作为培养基氮素添加剂能促进佛罗里达平菇、黑木耳和香菇的菌丝生长。除生料栽培培菌期间含羞草素明显自然降解及高压灭菌大量破坏含羞草素外,还发现菌丝对含羞草素有显著的降解作用。     

不同农业有机废弃物对白星花金龟生物学特性影响研究

【目的】白星花金龟Protaetia (Liocola) brevitarsis (Lewis)幼虫取食农作物秸秆、畜禽粪便等农业废弃物,在自然界中发挥着净化环境、变废为宝的作用。【方法】本文选用8种农牧业有机废弃物,包括腐熟沼渣、平菇菌糠、猪粪、牛粪、玉米秸秆、25%玉米秸秆+牛粪、50%玉米秸秆+牛粪、75%玉米秸秆+牛粪作为饲料,研究不同农业有机废弃物对白星花金龟生物学特性的影响。【结果】沼渣组和平菇菌糠组单雌产卵量较高,分别为130.17粒和117.00粒,显著高于猪粪、牛粪和玉米秸秆处理;在牛粪与玉米秸秆混配组,各处理单雌产卵量为101.50-108.67粒,不同混合比例间无显著差异。从幼虫孵化率比较,平菇菌糠组和猪粪组幼虫孵化率较高,分别为87.78%和82.22%;玉米秸秆及其与牛粪不同比例混合处理的幼虫孵化率均很低,仅为46.67%-57.78%。从幼虫化蛹率、羽化率比较,玉米秸秆添加不同比例牛粪处理组的化蛹率和羽化率均较高,分别达到90.00%-95.56%和88.89%-91.11%;沼渣、猪粪等单一物质处理的化蛹率和羽化率均较低,分别低于90%和70%。单一物质处理中,沼渣、平菇菌糠、牛粪、玉米秸秆处理组羽化后均为雌虫比例大于雄虫比例。玉米秸秆与牛粪混配组中,仅50%玉米秸秆+牛粪处理组为雌虫比例大于雄虫比例;雌、雄成虫的体长及体宽均在(17-19)mm、(10-11)mm之间,沼渣、猪粪和牛粪处理组体长略小。以不同农业有机废弃物饲喂的白星花金龟全世代发育历期中,牛粪饲喂组白星花金龟历期最短,为(315.29±0.55)d;沼渣饲喂组白星花金龟历期最长,为(330.75±1.76)d。【结论】不同农业有机废弃物均可作为白星花金龟繁育基质,并可为其幼虫转化处理农业有机废弃物提供理论依据。     

平菇菌糠提取液对酵母产量的影响

本文通过配制不同比例的平菇菌糠提取液,对酿酒酵母进行培养,经过细胞浓度测定,发现不同浓度的平菇菌糠提取液对酵母的增长均有促进作用。其中20%平菇菌糠提取液+1%葡萄糖为6.25%;20%平菇菌糠提取液+2%葡萄糖为15.81%;40%平菇菌糠提取液为13.97%;60%平菇菌糠提取液为18.75%;80%平菇菌糠提取液为19.29%;100%平菇菌糠提取液为21.69%,可以看出100%平菇菌糠提取液的促进效果是最为明显的。该研究证明平菇菌糠提取液可以代替常用的YPD培养基对酿酒酵母进行培养。     

桃木基质生产香菇综合评价

以桃木为主要栽培基质,分别设置不同质量分数（20%,40%,60%,80%）的桃木替代常规配方中的栎木进行香菇生产,考察不同比例桃木替代对香菇菌丝生长速度、产量、农艺性状及子实体中重金属和农药残留的影响。结果表明：与对照（80%栎木屑、18%麸皮和2%石膏）相比,一定比例的桃木屑添加（<60%）对香菇菌丝生长不产生影响,过高的桃木添加量（≥60%）会显著降低菌丝生长速度,满袋时间相应延长;随着桃木添加量的增加,总产量呈现先增加后降低的趋势,添加桃木对产量影响不显著,其中2号配方（40%栎木屑、40%桃木屑、18%麦麸、2%石膏）产量最高、菇型最好,生物学效率达到79.08%;添加60%以上的桃木配方提高了二级菇的比例,子实体整体较大;检测桃木完全替代的配方生产的第一潮香菇子实体的农药残留以及重金属,均不存在超标的现象,证实了桃木基质用于香菇生产的安全性。     

Efficient Production of Lumichrome by Microbacterium sp. Strain TPU 3598

Lumichrome is a photodegradation product of riboflavin and is available as a photosensitizer and fluorescent dye. To develop new efficient methods of lumichrome production, we isolated bacterial strains with high lumichrome productivity from soil. The strain with highest productivity was identified as Microbacterium sp. strain TPU 3598. Since this strain inductively produced lumichrome when cultivated with riboflavin, we developed two different methods, a cultivation method and a resting cell method, for the production of large amounts of lumichrome using the strain. In the cultivation method, 2.4 g (9.9 mmol) of lumichrome was produced from 3.8 g (10.1 mmol) of riboflavin at the 500-ml scale (98% yield). The strain also produced 4.7 g (19.4 mmol) of lumichrome from 7.6 g (20.2 mmol) of riboflavin (96% yield) by addition of riboflavin during cultivation at the 500-ml scale. In the resting cell method, 20 g of cells (wet weight) in 100 ml of potassium phosphate buffer, pH 7.0, produced 2.4 g of lumichrome from 3.8 g of riboflavin (98% yield). Since the lumichrome production by these methods was carried out in suspension, the resulting lumichrome was easily purified from the cultivation medium or reaction mixture by centrifugation and crystallization. Thus, the biochemical methods we describe here are a significant improvement in terms of simplicity and yield over the existing chemical, photolytic, and other biochemical methods of lumichrome production.     

Production and Properties of Alkaline Lipase from Alcaligenes sp. Strain No. 679

For the production of extracellular lipase by Alcaligenes species No. 679, NaNO₃, polyoxyethylene alkyl ether, Fe⁺⁺, sodium citrate and fructose were found to be effective. The enzyme was prepared by acetone precipitation from the filtrate of the culture broth of this strain. The enzyme was most active at pH 9.0 and 50°C, while 35% of its activity was lost on heat treatment at 60°C for 10 min. Sodium salts of bile acids stimulated the enzyme activity. This lipase could hydrolyse natural fats and oils as well as olive oil. During the hydrolysis of olive oil, monoglyceride was found to accumulate up to 70 mol percent. This lipase possesses special properties similar to those of pancreatic lipase as shown in the comparative experiments.     

Utilization of Ganglioside-Degrading Paenibacillus sp. Strain TS12 for Production of Glucosylceramide

Gangliosides, sialic acid-containing glycosphingolipids, are membrane constituents of vertebrates and are known to have important roles in cellular differentiation, adhesion, and recognition. We report here the isolation of a bacterium capable of degrading gangliotetraose-series gangliosides and a new method for the production of glucosylceramide with this bacterium. GM1a ganglioside was found to be sequentially degraded by Paenibacillus sp. strain TS12, which was isolated from soil, as follows: GM1a → asialo GM1 → asialo GM2 → lactosylceramide → glucosylceramide. TS12 was found to produce a series of ganglioside-degrading enzymes, such as sialidases, β-galactosidases, and β-hexosaminidases. TS12 also produced β-glucosidases, but glucosylceramide was somewhat resistant to the bacterial enzyme under the conditions used. Taking advantage of the specificity, we developed a new method for the production of glucosylceramide using TS12 as a biocatalyst. The method involves the conversion of crude bovine brain gangliosides to glucosylceramide by coculture with TS12 and purification of the product by chromatography with Wakogel C-300 HG.     

Optimizing Production of Extracellular Laccase from Grammothele Subargentea CLPS No. 436 Strain

The production of extracellular laccase by the Grammothele subargentea CLPS no. 436 strain in liquid cultures grown on a carbon-limited basal medium was significantly enhanced when culture conditions, including the addition of CuSO₄·5H₂O or veratryl alcohol, were consecutively optimized. A laccase activity as high as 1954.5 mU ml⁻¹ of liquid medium was obtained under optimum conditions, which corresponded to non-agitated cultures supplemented with 0.6 mM CuSO₄·5H₂O. Veratryl alcohol at 1 mM was less effective than CuSO₄·5H₂O for increasing laccase activity levels; the supplementation of veratryl alcohol resulted only in maximum levels of 44 mU ml⁻¹ in non-agitated cultures. This revised version was published online in July 2006 with corrections to the Cover Date.     

Analysis of Genes for Succinoyl Trehalose Lipid Production and Increasing Production in Rhodococcus sp. Strain SD-74

Succinoyl trehalose lipids (STLs) are promising glycolipid biosurfactants produced from n-alkanes that are secreted by Rhodococcus species bacteria. These compounds not only exhibit unique interfacial properties but also demonstrate versatile biochemical actions. In this study, three novel types of genes involved in the biosynthesis of STLs, including a putative acyl coenzyme A (acyl-CoA) transferase (tlsA), fructose-bisphosphate aldolase (fda), and alkane monooxygenase (alkB), were identified. The predicted functions of these genes indicate that alkane metabolism, sugar synthesis, and the addition of acyl groups are important for the biosynthesis of STLs. Based on these results, we propose a biosynthesis pathway for STLs from alkanes in Rhodococcus sp. strain SD-74. By overexpressing tlsA, we achieved a 2-fold increase in the production of STLs. This study advances our understanding of bacterial glycolipid production in Rhodococcus species.     

嗜热菌Anoxybacillus sp．DL3产蛋白酶条件及其酶学性质研究

目的：对Anoxybacillussp．DL3的产蛋白酶条件及其酶学性质进行研究,为下一步进行蛋白酶基因的克隆、表达提供依据。方法：应用常规方法液体培养细菌,研究温度、pH、培养基中碳源、氮源对菌株产蛋白酶的影响,硫酸铵盐析的方法提取酶液,并采用Folin法测酶活性。用紫外分光光度计在OD680hi／1测吸光值。并对提取的蛋白酶液进行酶的最适温度、pH以及酶的热稳定性和pH稳定性研究,向酶液中添加金属离子和EDTA、PMSF,研究其对酶活性的影响。结果：在培养基初始pH是6．5,培养温度为40℃时菌株产酶酶活性最大;培养基中以乳糖为碳源,酵母膏和硫酸铵为氮源,碳源与氮源的比例为1：2时,酶活最大。酶学性质研究结果显示：该酶的最适反应温度是55℃,最适反应pH是7．0;在50℃保温20min-80min内,酶活力下降幅度较小。60℃保温60min后,仍保持约60％的酶活。70℃保温60min后,残余酶活为30％。该酶在pH为6．0～8．0范围内,相对酶活差别不是很大,下降趋势大致相同。在强碱条件下,相对酶活下降很明显。Fe2＋、Cu2＋和Hg2＋对酶活性有明显的抑制作用;Ca2＋、Mg^2＋、Mn2＋等金属离子对酶活性有明显的促进作用;乙二胺四乙酸（EDTA）和苯甲基磺酰氟（PMSF）对酶活性也有一定抑制作用。结论：Anoxybacillussp．DL3所产的蛋白酶为嗜热中性蛋白酶,此酶具有较好的热稳定性和pH耐受性,该菌株具有进一步开发、利用的价值。     

Strain Design of Ashbya gossypii for Single-Cell Oil Production

Single-cell oil (SCO) represents a sustainable alternative for the oil industry. Accordingly, the identification of microorganisms with either higher lipidogenic ability or novel capacities for the transformation of raw materials constitutes a major challenge for the field of oil biotechnology. With this in mind, here, we were prompted to address the lipidogenic profile of the filamentous hemiascomycete Ashbya gossypii, which is currently used for the microbial production of vitamins. We found that A. gossypii mostly accumulates unsaturated fatty acids (FAs), with more than 50% of the total FA content corresponding to oleic acid. In addition, we engineered A. gossypii strains both lacking the beta-oxidation pathway and also providing ATP-citrate lyase (ACL) activity to block the degradation of FA and to increase the cytosolic acetyl-coenzyme A (CoA) content, respectively. The lipidogenic profile of the newly developed strains demonstrates that the mere elimination of the beta-oxidation pathway in A. gossypii triggers a significant increase in lipid accumulation that can reach 70% of cell dry weight. The use of A. gossypii as a novel and robust tool for the production of added-value oils is further discussed.     

Hydrogen Gas Production by an Ectothiorhodospira vacuolata Strain

A hydrogen gas (H₂)-producing strain of Ectothiorhodospira vacuolata isolated from Soap Lake, Washington, possessed nitrogenase activity. Increasing evolution of H₂ with decreasing ammonium chloride concentrations provided evidence that nitrogenase was the catalyst in gas production. Cells were grown in a mineral medium plus 0.2% acetate with sodium sulfide as an electron donor. Factors increasing H₂ production included addition of reduced carbon compounds such as propionate and succinate, increased reducing power by increasing sodium sulfide concentrations, and increased energy charge (ATP) by increasing light intensity.     

Plasmid-associated Bacteriocin Production by a Lactobacillus plantarum Strain

A Lactobacillus plantarum strain, LTF154, isolated from a fermented sausage, produces a bacteriocin, designated plantacin 154. Plantacin 154 was stable to heat treatment, and its activity was sensitive to proteolytic enzymes. The molecular mass, as indicated by activity detection after SDS-PAGE, was estimated to be 3.0 kDa or less. A plasmid-curing experiment and transformation analysis indicated that a 9.5-MDa plasmid, pLP1542, may be involved in the production of plantacin 154.     

Pectin Lyase Production by a Penicillium italicum Strain

Growth and concomitant production of an extracellular pectin lyase (PL) [poly(methoxylgalactosiduronate) endolyase; EC 4.2.2.10] were investigated in a group of 16 fungi grown in liquid medium containing pectin as a supplementary carbon source. Culture filtrates of both Penicillium italicum (CECT 2294) and P. expansum (CECT 2275) showed the highest PL activity and contained polygalacturonase but not pectinesterase activity. The effect of the inoculum size, the carbon source (sucrose and glucose syrup), and the presence of pectin on the production of PL by P. italicum was studied. The presence of 2.6 mM glycerophosphate in the culture medium enhanced the appearance of PL but was not inhibitory for the in vitro activity. However, glycerol inhibited the enzyme nearly 50% at such a concentration.