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51.
本研究以鲍姆桑黄Sanghuangporus baumii为研究对象,通过测定段木栽培一年生、二年生、三年生子实体粗蛋白质、粗脂肪、粗纤维、氨基酸、多糖、三萜、总黄酮、总酚含量和抗氧化活性(ABTS和FRAP),探究生长年限对段木栽培桑黄子实体营养、活性成分及抗氧化活性的影响.结果表明,生长年限对上述10个指标均产生了...  相似文献   
52.
陈万超  张俊峰  吴迪  张忠  李文  汪雯翰  王琨  杨焱 《菌物学报》2021,40(9):2364-2375
本研究对38个不同批次和菌龄的椴木栽培鲍姆桑黄孔菌Sanghuangporus baumii子实体醇提物进行了高效液相色谱(HPLC)分析,建立了S. baumii醇提物HPLC指纹图谱,提取得到27个共有峰信息(P1-P27);同时,对38个样品醇提取的Trolox等价抗氧化能力(TEAC)进行分析,基于正交偏最小二乘(OPLS)回归建立了抗氧化活性预测模型,潜变量数为3,交互验证所得累积模型预测参数(Q2)为0.803,变量累积解释指标(R2X)和(R2Y)分别为0.574和0.954,相关系数平方(R2)为0.954,经验证模型可以获得良好的预测效果,可以准确反映谱峰与活性之间相关关系;利用模型变量投影重要性(VIP)指标筛选得到14个共有峰对抗氧化活性具有显著贡献。研究获得的鲍姆桑黄孔菌抗氧化谱效关系模型为桑黄原料活性的预测提供了有效的方法,可辅助指导鲍姆桑黄孔菌活性化合物的分离纯化,也为鲍姆桑黄孔菌栽培子实体的品质控制提供了技术手段。  相似文献   
53.
桑黄粗多糖除蛋白及抗肿瘤活性   总被引:1,自引:0,他引:1  
旨在研究Sevag法除桑黄粗多糖中蛋白的最佳工艺,并通过噻唑蓝(MTT)细胞比色法测定除蛋白前后桑黄多糖的抗肿瘤活性。在单因素试验Sevag用量、氯仿与正丁醇体积比、萃取次数、震荡时间的基础上,设计正交试验,经过方差分析,确定Sevag法除桑黄粗多糖蛋白的最佳方案;并且对除蛋白后多糖与粗多糖进行体外抗肿瘤实验。Sevag法除桑黄粗多糖蛋白的最佳工艺:Sevag用量50 mL、V(氯仿)/V(正丁醇)=3、最佳萃取次数6次、最佳振荡时间20 min,在此条件下,多糖的得率为64.8%。体外细胞试验表明除蛋白后多糖与粗多糖对肿瘤细胞EC109和SiHa的抑制率没有明显差异。  相似文献   
54.
Phellinus robustus produced both laccase (700–4,000 U l−1) and manganese peroxidase (MnP) (1,000–11,300 U l−1) in fermentation of nine food wastes, whereas Ganoderma adspersum produced only laccase (600–34,000 U l−1). Glucose provided high laccase and MnP activity of P. robustus but repressed enzyme production by G. adspersum. Ammonium sulphate and ammonium tartrate increased the P. robustus laccase yield (3-fold), whereas the accumulation of MnP was not enhanced by additional nitrogen.  相似文献   
55.
All the fractions of Phellinus linteus mycelia showed anti-tumor activity toward solid tumors planted in mice. The highest anti-tumor activity of 81.2% was observed in the protein–glucan complex obtained by precipitating the 24% NaOH extract at pH 6.0. This protein–glucan complex consisted of 39.3% polysaccharide and 49.4% protein. Its 13C- and 1H-NMR data showed that the main glucan part of the complex was simple α-1,3-glucan chains.  相似文献   
56.
We compared the immunomodulating activities in mice of extracts from Phellinus linteus grown on germinated brown rice (PB), Phellinus linteus (PL) alone, and germinated brown rice (BR) alone. The PL, BR and PB-treated mice were administered with the respective extract (2 mg/head/day) by oral gavage for 4 weeks. All extracts markedly decreased the IgE production and allergic responses in serum and splenocytes. PL and PB increased the proportion of CD4+ but not CD8+ T cells in splenocytes. Cytokine production was significantly augmented in all treated mice; the concentration of IFN-γ was greater in the PL, BR and PB mice than in the control group. The concentration of IL-10 was lower in the BR group than in the other groups. These results may be related to the suppression of IgE production. We conclude that PB modulated the immune responses of IgE production and Th1/Th2 cytokine secretion in murine splenocytes.  相似文献   
57.
Abstract

Objectives

Ionizing radiation induces severe oxidative stress in the body resulting an imbalance in prooxidant and antioxidant status in the cell. The aim of the present study is to investigate the protective effect of polysaccharide protein complex (PPC-Pr) isolated from the mushroom Phellinus rimosus against the oxidative stress induced by gamma radiation.

Methodology

PPC-Pr complex was isolated from the aqueous extracts of P. rimosus. The complex was administered to Swiss albino mice at a concentration of 5 and 10 mg/kg body weight intraperitoneally for 5 days consecutively and exposed to 4 Gy of gamma irradiation. Animals were sacrificed 1 day after irradiation and the antioxidant parameters such as glutathione, glutathione peroxidase, superoxide dismutase, catalase, glutathione reductase as well as lipid peroxidation were evaluated in both liver and brain tissues to evaluate oxidative stress. Amifostine, a standard radioprotective agent, was used as a positive control. In vitro DNA damage was assessed using the comet assay. Survival studies were also carried out to determine the protective role of PPC-Pr against radiation-induced delayed oxidative stress.

Results

PPC-Pr treatment enhanced the declined levels of antioxidants and comet parameters to a significant level, indicating its antioxidant as well as DNA protecting potential. Significant increase in the survival rate of animals was also observed in irradiated animals treated with PPC-Pr complex. The results were comparable to the standard drug amifostine.

Discussion

The results indicate profound effects of PPC-Pr against radiation-induced oxidative stress. The findings suggest potential therapeutic use of PPC-Pr in radiotherapy.  相似文献   
58.
59.
采用肝癌H22荷瘤小鼠的肿瘤模型,对火木层孔菌(桑黄)Phellinus igniarius发酵菌粉及其各提取物组分的体内抗肿瘤活性进行评价。结果表明,火木层孔菌发酵菌粉及其各提取物组分对荷瘤小鼠肝癌H22都具有一定的抗肿瘤作用并能延长荷瘤小鼠生存期,其中,火木层孔菌发酵菌粉(1,000mg/kg/d)及其组分I(I多糖组分)(360mg/kg/d)具有较为显著的抗肿瘤作用,抑瘤率分别为33.5%和40.3%。组织病理学研究结果表明在菌粉及其多糖组分作用后,肿瘤细胞坏死细胞明显增多,免疫组化检测表明火木层孔菌发酵菌粉及其多糖组分能明显的降低瘤组织中Bcl-2基因蛋白的表达,提高小鼠瘤组织中的Bax基因蛋白的表达。火木层孔菌发酵菌粉及其多糖组分具有较好的体内抗肿瘤活性。  相似文献   
60.
Yang Y  Zhang J  Liu Y  Tang Q  Zhao Z  Xia W 《Carbohydrate research》2007,342(8):1063-1070
PIP60-1, a novel heteropolysaccharide isolated from fruiting bodies of the medicinal fungus, Phellinus igniarius, has a molecular weight of 1.71 x 10(4)Da and is composed of L-fucose, D-glucose, D-mannose, D-galactose and 3-O-Me-D-galactose in a ratio of 1:1:1:2:1. A structural investigation of PIP60-1 carried out using sugar and methylation analyses, combined with (1)H and (13)C NMR spectroscopy, including COSY, TOCSY, NOESY, HSQC and HMBC experiments, established the repeating unit of the polysaccharide as the following: [structure: see text]  相似文献   
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