Effects of different graphene-based nanomaterials as elicitors on growth and ganoderic acid production by Ganoderma lucidum

Graphene-based nanomaterials (GBNs) have attracted considerable interest nowadays due to their wide range of applications. However, very little attention has been paid to the application of nanomaterials as potential elicitors for production of valuable metabolites. Herein, aiming to earn insight into effects of nanomaterials on secondary metabolite biosynthesis by medicinal fungi, we evaluated the influence of GBNs on growth and production of ganoderic acid (GA) by Ganoderma lucidum in submerged culture. Graphene oxide (GO), reduced graphene oxide (rGO), and rGO/Fe₃O₄ nanocomposite were synthesized successfully and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy analysis. The prepared nanomaterials were added to the culture of G. lucidum at final concentrations of 50, 100, and 150 mg/L on Day 5. The results showed that the elicitation of G. lucidum with GO and rGO decreased the cell dry weight and GA production slightly, especially in higher concentrations. However, rGO/Fe₃O₄ nanocomposite not negatively affected cell growth and improved GA production. G. lucidum growth rate responded to elicitation experiments differently and depended on the type of nanomaterials and their concentrations, but almost all GBNs caused an increase in GA content (mg/100 mg dry weight). Also, field emission scanning electron microscopy morphological study showed that under elicitation, mycelia were more condensed and tightly stacked together. The findings from this study may suggest that GBNs in low concentrations could be applied as elicitors to secondary metabolites production from higher fungus, but further environmental, physiological, and biological studies required.     

Improvement of ganoderic acid and Ganoderma polysaccharide biosynthesis by Ganoderma lucidum fermentation under the inducement of Cu2+

The cell growth and total accumulation of bioactive metabolites were significantly improved by Cu²⁺ addition during the submerged fermentation of medicinal mushroom Ganoderma lucidum. A mathematical model, constructed by response surface methodology combination with full factorial design, was applied to study the synergic effect of Cu²⁺ addition concentration and addition time. The optimal Cu²⁺ inducement strategy for the cell growth were different from those for the biosynthesis of ganoderic acid (GA) and Ganoderma polysaccharide. A multiple additions strategy of Cu²⁺ by adding each 1 mM Cu²⁺ on day 2, 6, 8 and 2 mM Cu²⁺ on day 4 was developed to enhance total accumulation of GA and extracellular polysaccharides. The highest GA content reached 3.0 ± 0.1 mg per 100 mg DW, which was increased by 76.5% and 33.9% compared with the control without Cu²⁺ addition and the peak value predicted by the constructed mathematical model, respectively. While, relatively higher addition concentration of Cu²⁺ (i.e., 5 mM) on the culture of day 4 led to higher content and total production of intracellular polysaccharides. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010     

灵芝深层发酵生产四环三萜酸的研究

从灵芝深层发酵产物中分离得到三种四环三萜酸,命名为灵芝酸Ｍ１,Ｍ２,Ｍ３,在２５Ｌ发酵罐上研究了发酵条件对灵芝酸产量的影响,以及灵芝酸的代谢形成特征。结果表明最适发酵条件是：温度３０℃;通风量１：０．７５ｖ／ｖ／ｍ;搅拌转速１８０ｒ／ｍｉｎ;发酵时间８０ｈ,此时灵芝酸的最高产量是０．３６ｇ／Ｌ发酵液。抑菌实验表明上述灵芝酸能够抑制大肠杆菌,产气杆菌、肠炎杆菌、金黄色葡萄球菌和枯草芽孢杆菌的生长。     

不同植物药提取物对灵芝细胞生长和胞内三萜产物形成的影响

研究了不同植物药的水提和醇提物对灵芝深层发酵过程中菌丝量和胞内三萜产量的影响。将不同植物药的水提物和醇提物分别加入到发酵基础培养基中,培养7d后检测灵芝生物量和胞内三萜含量。结果表明,金银花和枸杞子水提物添加浓度为100mg/L时,可促进灵芝细胞的生长（p＜0.05）。连翘水提物对灵芝生长和胞内三萜的形成都有显著促进作用,当连翘水提物浓度为400mg/L时,胞内三萜产量从对照的（192.54±8.99）mg/L提高到（302.52±3.79）mg/L。金银花和枸杞子醇提物浓度为200mg/L时能显著促进灵芝细胞生长;枸杞子醇提物在同样浓度下还能促进灵芝胞内三萜的形成。但板蓝根和银杏叶水提物和醇提物都对灵芝的细胞生长和胞内三萜形成有较强的抑制作用。     

菌草灵芝与段木灵芝的功效成分的比较研究

测定并比较菌草灵芝和不同产地的段木灵芝中的粗多糖、三萜类物质和孢子油中三萜类物质的含量和孢子油得率的差异。结果表明,菌草灵芝和不同产地的段木灵芝中的粗多糖、三萜类物质和孢子油中三萜类物质的含量和孢子油得率存在着差异,菌草灵芝中的粗多糖、三萜类物质和孢子油中三萜类物质的含量和孢子油得率都高于段木灵芝。     

灵芝三萜酸分批发酵的非结构动力学模型

研究了灵芝胞内和胞外三萜酸在30L发酵罐中分批发酵的动力学特征。利用Sigmoid函数构建了灵芝细胞生长、底物消耗、胞内和胞外三萜酸的非结构动力学模型,并根据Boltzmann拟合求解出各模型参数。结果表明,各模型预测值能够较好地吻合实验实测值。灵芝细胞比生长速率在第2.5天达到最大值（μmax）,为0.700d?1;葡萄糖比消耗速率在第2.4天达到最大值（qS, max）为1.060d?1;胞内三萜酸比合成速率在第4.7天达到最大值（qITA, max）为11.345mg/(g·d);胞外三萜酸比合成速     

Link between spatial structure of microbial communities and degradation of a complex mixture of volatile organic compounds in peat biofilters

AIMS: To investigate the relationships between the operation of the volatile organic compound (VOC) removal biofilter and the structure of microbial communities, and to study the impact on degradation activities and the structuring of microbial communities of biofilter malfunctions related to the qualitative composition of the polluted air. METHODS AND RESULTS: A microbiological study and a measurement of biodegradation activities were simultaneously carried out on two identical peat-packed columns, seeded with two different inocula, treating polluted air containing 11 VOCs. For both reactors, the spatial structure of the microbial communities was investigated by means of single-strand conformation polymorphism (SSCP) analysis. For both reactors, stratification of degradation activities in function of depth was observed. Oxygenated compounds were removed at the top of the column and aromatics at the bottom. Comparison of SSCP patterns clearly showed a shift in community structure in function of depth inside both biofilters. This distribution of biodegradation activities correlates with the spatialization of microbial density and diversity. Although the operating conditions of both reactors were identical and the biodegradation activities similar, the composition of microflora differed for biofilters A and B. Subdivision of biofilter B into two independent parts supplied with polluted air containing the complex VOC mixture showed that the microflora having colonized the bottom of biofilter B retained their potential for degrading oxygenated compounds. CONCLUSIONS: This work highlights the spatialization of biodegradation functions in a biofilter treating a complex mixture of VOCs. This distribution of biodegradation activities correlates with the spatialization of microbial density and diversity. SIGNIFICANCE AND IMPACT OF THE STUDY: This vertical structure of microbial communities must be taken into consideration when dealing with the malfunctioning of bioreactors. These results are also useful information about changes in microbial communities following natural or anthropogenic alterations in different ecosystems (soils and sediments) where structuring of microbial communities according to depth has been observed.     

中药提取液对灵芝深层发酵的影响

我国中医药历史悠久 ,中药资源丰富 ,为保证广大人们的身体健康起到巨大作用。但近几十年来 ,我国在中药现代化方面进展缓慢 ,其中原因之一就是中药加工技术陈旧[1] ,近来有学者提出了中药发酵制药技术[1,2 ] 。药用真菌是中药的组成部分 ,它们中的许多种类都能以液体发酵进行生产[3] ,以适当的中药为培养基或在培养基中添加适量的中药 ,利用它们强大的分解转化能力 ,不仅可对中药中的纤维、糖类和蛋白等物质加以利用 ,而且在代谢过程中可能对中药中的一些成分进行转化 ,从而提高中药活性成分在复合制剂中的比例及效价 ;另外中药中的某些成…     

灵芝悬浮培养中添加微颗粒Talc对灵芝酸产生的影响

灵芝酸是灵芝中重要的药理活性物质,其低产量限制了它的广泛应用和深入研究,高效提高液体发酵中灵芝酸的含量十分必要。以CGMCC 5.65为材料,在悬浮培养条件下,研究添加微颗粒Talc对灵芝酸产生的影响。结果表明,微颗粒Talc添加显著减小了灵芝细胞粒径,对照组为(3.33±0.16)mm,15g/L微颗粒Talc添加组为(2.04±0.12)mm。灵芝细胞中单体灵芝酸和总灵芝酸的含量在微颗粒Talc添加条件下也显著提高。15g/L微颗粒Talc添加组的总灵芝酸含量达到(1.51±0.02)mg/100mg细胞干重,GA-Mk、GA-T和GA-Me的含量最高为(6.02±0.29)、(5.08±0.14)和(1.71±0.09)μg/100mg细胞干重,分别是对照的1.6、4、1.9和1.4倍。另外,15g/L微颗粒Talc添加条件下鲨烯和羊毛甾醇的最大积累量分别为(3.69±0.23)和(34.86±6.41)μg/100mg细胞干重,是对照的2.6和4.2倍;灵芝酸生物合成途径关键基因fps和cyp-5150l8的表达量最高为对照的2.35和1.53倍。     

Effects of fermentation products of Ganoderma lucidum on growth performance and immunocompetence in weanling pigs

The purpose of this study was to test fermentation, for its products of a Chinese medicinal mushroom, Ganoderma lucidum, cultured by submerged fermentation for its effect on growth performance and immunocompetence in weanling piglets. In Experiment 1, 72 weanling piglets were allotted to one of four treatments receiving these fermentation products (GLF, expressed as amount of β-glucans) at 0 (control), 50, 100, and 150 mg/kg feed for 4 weeks. The results showed that at a supplementation level of 50 mg/kg feed, GLF caused the best growth performance, the highest pseudorabies antibody titre, and a decrease of blood glucose level. It was also demonstrated that GLF up-regulated the cell-mediated immune response related cytokines (IL-2, IFN-γ, and TNF-α) expression in different lymphoid tissues. After challenging with porcine circovirus (PCV) type 2 (Experiment 2), a supplementation with 50 mg GLF per kg feed also inhibited PCV-2 virus amplification, and ameliorated lymphocyte depletion in different lymphoid tissues. Conclusively, feed supplemented with GLF at 50 mg/kg could be beneficial to counteract the physiological stress in weanling piglets.     

Enhancement of exopolysaccharide production from Ganoderma lucidum using a novel submerged volatile co-culture system

Based on the impact of volatile organic compounds (VOCs) on secondary metabolite pathways, a novel submerged volatile co-culture system was constructed, and the effects of thirteen fungal and bacterial VOCs were investigated on Ganoderma lucidum exopolysaccharides production. The results demonstrated at least a 2.2-fold increase in exopolysaccharide (EPS) specific production yield in 6 days submerged volatile co-culture of G. lucidum with Pleurotus ostreatus. Therefore, P. ostreatus was selected as a variable culture, and the effects of agitation speed, inoculum size, initial pH, and co-culture volume on EPSs production were investigated using a Taguchi L₉ orthogonal array. Finally, the highest concentration of EPSs (3.35 ± 0.22 g L^?1) was obtained under optimized conditions; initial pH 5.0, inoculum size 10%, 150 rpm, and 3:1 volume ratio of variable culture to main culture.     

Ganoderma lucidum: A potential pleiotropic approach of ganoderic acids in health reinforcement and factors influencing their production

Ganoderma lucidum (G. lucidum) main attractive pharmacological characteristics are antitumor and immunomodulatory activities which are chiefly associated with its two principal bioactive compounds, those are polysaccharides and triterpenoids. Ganoderic acids (GAs) are one of the most discovered triterpenoids of G. lucidum among various triterpenoids. The prominent medicinal mushroom G. lucidum possesses GAs as essential bioactive constituents that are highly oxygenated lanostane-type triterpenoids. GAs exhibit diverse potential action against numerous diseases such as anticancer, antioxidant, anti-inflammatory, anti-HIV, cardioprotective, antiallergic, antihepatotoxic, neuroprotective and antinociceptive properties. GAs act through different mechanisms that include cytotoxic, apoptosis, inducing cell cycle arrest, inhibition of topoisomerases, antiproliferation, anti-invasion, inhibition of NF-kB AP1/uPA, farnesyl protein transferase and JAK-STAT3 pathway. The miraculous effects of GAs fascinate the researchers for their production. Various environmental factors such as biochemical signals, nutritional and physical that influence the biosynthesis of GA. However, the scarcities of pure compounds or accurately characterized extracts are the main problem of clinical studies. Substantial steps are required for characterized extracts of active compounds. This review contributes a thorough insight into the mode of actions of GAs and their possible reinforcements to overcome various diseases.     

灵芝三萜类成分与药理学研究进展

灵芝的化学成分有三萜类、多糖、生物碱、有机酸、核苷、氨基酸、酶类及微量元素等 ,其主要成分是三萜类化合物中的灵芝酸。由于灵芝化学成分的多样性 ,使灵芝具有较广泛的药理活性 ,主要包括抗肿瘤作用 ;调节免疫系统、心血管系统、神经系统、呼吸系统的作用 ;保肝、抗衰老、抗病毒、消炎抗菌、放射保护作用 ;清除氧自由基和抗氧化、致突变、活血化淤作用 ;对学习和增强记忆有良好的影响。     

灵芝抗氧化清除自由基作用的研究

文中综述了灵芝的抗氧化清除自由基作用。灵芝对各种因素引起的脑、心脏、胰腺、肝脏、胃肠道、肾脏和其他重要脏器的脂质过氧化损伤具有明显的保护作用。灵芝可显著减少脂质过氧化产物丙二醛(MDA)的含量,增强抗氧化酶如超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)以及其他抗氧化酶的活性。稹灵芝对体外培养的巨噬细胞(小鼠)、胰岛细胞(小鼠)、大脑皮层细胞(大鼠)、嗜铬细胞瘤细胞(大鼠)、血管内皮细胞(大鼠、人)和皮肤角质细胞(人)的氧化损伤具有明显保护作用。灵芝在体内外对不同动物模型和细胞模型的抗氧化清除自由基作用可能与其免疫调节、抗肿瘤、降血压、降血糖、保肝、心血管保护和抗衰老作用的机制有关。     

灵芝钙调蛋白基因CaM的克隆与功能分析

灵芝是我国传统的食药用真菌,具有广泛的免疫调节功能并含有多种生物活性成分。灵芝酸是灵芝的主要次生代谢产物之一,具有较高商业价值。钙调蛋白（calmodulin,CaM）作为真核生物中重要的Ca ²⁺信使,能够参与生长发育、次生代谢等重要生理过程。本研究通过序列分析发现,灵芝CaM基因序列编码149个氨基酸,与其他物种CaM蛋白高度保守。该蛋白含有4个完整的EF-hand结构域,并且在每个EF-hand结构域中,都含有一个保守的D-x-D基序。进一步构建筛选了灵芝CaM沉默转化子,检测CaM在灵芝生长发育及次生代谢过程中的功能。结果显示,CaM沉默转化子中灵芝酸含量比WT降低约34%。沉默CaM后菌丝生长速率与WT相比降低40%。该结果说明CaM在灵芝生长及次生代谢过程中具有重要作用,为在真菌中研究CaM功能及调控途径提供参考。