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81.
灵芝多糖抗肿瘤作用的初步探讨   总被引:6,自引:0,他引:6  
目的 :初步探讨灵芝多糖对小鼠肿瘤的抑制作用。方法 :观察灵芝多糖对 S180 、U14腹水型荷瘤小鼠生存期的影响 ,了解灵芝多糖对 S180 、U14、H2 2 肿瘤细胞有无直接杀伤作用 ,以寻找治疗肿瘤的新方法。结果 :灵芝多糖能够显著延长荷瘤小鼠的生存期 (P<0 .0 5) ,治疗组小鼠的生存期比对照组小鼠的生存期明显延长 ,但是灵芝多糖对肿瘤细胞无直接杀伤作用 (P<0 .0 5)。结论 :灵芝多糖抗肿瘤作用是通过机体的免疫系统介导的。  相似文献   
82.
A comparison of vanadium-rich activity of three species fungi of Basidiomycetes, Ganoderma lucidum, Coprinus comatus, and Grifola frondosa, was studied. By fermentation and atomic absorption spectroscopy analysis, the biomass of G. lucidum and G. frondosa declined rapidly when the concentration of vanadium exceeded 0.3% but the biomass of C. comatus did not decline rapidly until the concentration of vanadium exceeded 0.4% and the content of vanadium accumulated in the mycelia was 3529.3 μg/g. After the mice were administered (intragastrically) with vanadium-rich C. comatus, the blood glucose of alloxan-induced hyperglycemic mice was decreased (p < 0.05) and the body weight of the alloxan-induced hyperglycemic mice was increased gradually. Thus, we selected C. comatus to absorb vanadium and chose 0.4% as the optimal concentration of vanadium for the pharmacological works.  相似文献   
83.
Introduction – Ganoderma, one of the best‐known traditional Chinese medicines, has attracted considerable attention owing to the fact that dozens of polysaccharides isolated from it have shown diverse and potentially significant pharmacological activities. However, no work has been reported on the analysis of monosaccharide composition of polysaccharide isolated from the aqueous extract of Ganoderma atrum yet. Objective – To develop a simple and sensitive GC‐based method for the analysis of monosaccharide composition of purified polysaccharides in Ganoderma atrum. Methodology – The polysaccharide was first hydrolysed to give the constituent monosaccharides, which were subsequently derived into acetylated aldononitriles and analysed by gas chromatography using a capillary column packed with a (5%phenyl) methylpolysiloxane stationary phase with the addition of acetyl inositol as the inner standard. High‐performance liquid chromatography was also used for comparison. Results – The stable derivatives of the most common monosaccharides could be separated and reproducibly determined with high sensitivity. The limits of detection and quantification were 0.013 and 0.043 mg/mL, respectively. The intermediary precision values (expressed as the RSD) were less than 10%. The mean recovery of the method was 100 ± 3%, with RSD values of less than 5%. The results obtained from GC and HPLC methods were found to be close to each other within acceptable error ranges. Conclusion – This study demonstrated that the developed method could be applied as an accurate method for the compositional analysis of monosaccharides in the field of biological and biochemical study. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
84.
真菌免疫调节蛋白家族(Fungi immunoregulatory proteins,FIPs)各成员所具有的免疫调节和抗肿瘤活性已被广泛研究。本研究利用毕赤酵母表达系统对其成员Lz-8进行了重组表达。以毕赤酵母突变株GS115为表达宿主细胞,PCR和DNA测序结果均显示Lz-8的cDNA已被成功地整合入酵母基因组。聚丙烯酰胺凝胶电泳(SDS-PAGE)、激光解析飞行时间质谱(MALDI-TOF-MS)和免疫学实验均被用于重组表达蛋白的检测。实验结果表明Lz-8在毕赤酵母表达系统中得到成功表达,在SDS-PAGE中可观察到分子量为14000D的单一条带,MALDI-TOF-MS的实验结果显示rLz-8的分子量为12722D。在相关的免疫学实验中,rLz-8可引起绵羊血红细胞凝集,但对人血4种血型的红细胞并没有凝集作用,rlz-8还可诱导巨噬细胞吞噬作用,均与其他报道中的实验结果吻合。以上结果表明,本实验已成功地利用毕赤酵母表达系统对Lz-8进行重组表达。  相似文献   
85.
药用昆虫蜣螂对灵芝发酵和抗小鼠肝癌活性的影响   总被引:3,自引:0,他引:3  
采用液体深层发酵方式,研究了药用昆虫蜣螂对灵芝细胞生长、关键活性产物发酵动力学和抗小鼠肝癌活性的影响。结果表明,药用昆虫蜣螂在各添加浓度下对灵芝的细胞生长均无显著促进作用;但在添加量为5g/L时,对灵芝多糖和灵芝三萜的发酵动力学有显著影响(P<0.05),在发酵第7天时,灵芝总多糖和总三萜的产量分别达到2.81g/L和539.0mg/L(对照组分别为2.25g/L和428.2mg/L)。小鼠体内抗肝癌结果表明,灵芝对照发酵物的抑癌率为41.61%,灵芝-蜣螂配合物的抑癌率为42.24%;而补加蜣螂发酵后的灵芝加蜣发酵物的抑癌率高达57.21%,与灵芝对照发酵物的抑癌率相比,提高了37.49%。研究表明,采用昆虫蜣螂补料-分批发酵后,灵芝发酵物抗小鼠肝癌的活性得到显著增强。  相似文献   
86.
药用昆虫蜣螂对灵芝多糖生物合成的影响   总被引:4,自引:0,他引:4  
采用液体深层发酵方式,研究了几种药用昆虫对灵芝多糖生物合成的影响。结果表明,药用昆虫蜣螂在添加量为5g/L时能显著促进灵芝胞内多糖(IPS)和胞外多糖(EPS)的形成(P<0.05)。胞内多糖和胞外多糖的产量分别由对照的(1.93±0.09)g/L和(520.3±20.2)mg/L提高到(2.41±0.12)g/L和(608.9±20.2)mg/L。灵芝胞内多糖和胞外多糖在DEAE纤维素柱上都可分离得到5种主要组分,其中IPS-1和EPS-1分别为2类多糖的主要组分。进一步用凝胶柱分离显示,IPS-1由3个单个的组分组成,EPS-1由2个单个的组分组成。添加蜣螂发酵后,灵芝胞内多糖和胞外多糖中没有出现新的组分,且各组分的相对含量也没有显著变化(P>0.05),提示添加蜣螂发酵后,灵芝胞内多糖和胞外多糖主要组分的合成途径并未改变。  相似文献   
87.
As a result of an interest in natural derived metabolites, lignicolous fungi have taken on great importance in biochemical investigations. In the present study, antioxidative screening analyses have included in vitro testing of different extracts (aqueous, methanol, chloroform) of four fungal species using three different assays: Fe2+/ascorbate-induced lipid peroxidation by TBA assay, the neutralisation of OH· radicals and the radical scavenging capacity with the DPPHk]assay. TLC analysis confirmed the existance of phenolics in the extracts, but also indicates the presence of some other compounds. The obtained results indicate that MeOH extracts manifested a degree of activity higher than that of CHCl3 extracts. With respect to antioxidative activity, the extracts can be ranged in the following declining order: G. lucidum, G. applanatum, M. giganteus and F. velutipes. These results suggest that analyzed fungi are of potential interest as sources of strong natural antioxidants that could be used in the food industries and nutrition.  相似文献   
88.
Tang W  Liu JW  Zhao WM  Wei DZ  Zhong JJ 《Life sciences》2006,80(3):205-211
Ganoderma lucidum is a well-known traditional Chinese medicinal herb containing many bioactive compounds. Ganoderic acid T (GA-T), which is a lanostane triterpenoid purified from methanol extract of G. lucidum mycelia, was found to exert cytotoxicity on various human carcinoma cell lines in a dose-dependent manner, while it was less toxic to normal human cell lines. Animal experiments in vivo also showed that GA-T suppressed the growth of human solid tumor in athymic mice. It markedly inhibited the proliferation of a highly metastatic lung cancer cell line (95-D) by apoptosis induction and cell cycle arrest at G(1) phase. Moreover, reduction of mitochondria membrane potential (Delta psi(m)) and release of cytochrome c were observed during the induced apoptosis. Our data further indicate that the expression of proteins p53 and Bax in 95-D cells was increased in a time-dependent manner, whereas the expression of Bcl-2 was not significantly changed; thus the ratio of Bcl-2/Bax was decreased. The results show that the apoptosis induction of GA-T was mediated by mitochondrial dysfunctions. Furthermore, stimulation of the activity of caspase-3 but not caspase-8 was observed during apoptosis. The experiments using inhibitors of caspases (Z-VAD-FMK, Z-DEVD-FMK and Z-IETD-FMK) confirmed that caspase-3 was involved in the apoptosis. All our findings demonstrate that GA-T induced apoptosis of metastatic lung tumor cells through intrinsic pathway related to mitochondrial dysfunction and p53 expression, and it may be a potentially useful chemotherapeutic agent.  相似文献   
89.
黑灵芝提取物清除DPPH自由基的作用   总被引:22,自引:0,他引:22  
以黑灵芝为研究对象,采用不同方法提取黑灵芝中的有效成分,以BHT和抗坏血酸为对照品,采用DPPH.法研究各种提取物对自由基的清除作用。结果表明:微波萃取法是最适合提取黑灵芝中有效成分的现代方法,不仅产率高,而且速度快,节能;不同溶剂提取物对DPPH自由基清除率强弱依次为95%乙醇>丙酮>水>氯仿,提取物用量与清除能力成量效关系;黑灵芝的丙酮提取物浓度达到1 mg/mL时已超过10 mg/mL BHT的抗氧化效果,相当于0.5 mg/mL浓度抗坏血酸的抗氧化效果。  相似文献   
90.
研究了超高压处理对灵芝生长及其漆酶合成的影响,试验结果表明:灵芝致死率随处理压力的增大而增加,在150MPa下处理30min获得了一株生物量和漆酶产量都大幅增加的菌株G1502,其最大生物量及酶活分别比出发菌株提高了19.34%和282.67%,发酵时间也缩短了1d。  相似文献   
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