珍稀药用真菌桑黄的研究进展

桑黄是目前生物治癌领域中最有效率的一种药用真菌.该文综述了桑黄的分类学地位、化学成分、药理作用以及液体发酵等方面的研究进展,并提出了展望.     

桑黄菌原生质体的分离与再生研究

目的：研究桑黄菌原生质体分离与再生的条件。方法：研究以菌丝体为材料的不同酶解条件对桑黄菌原生质体产量的影响及不同再生条件对桑黄菌原生质体再生率的影响。结果：在1.5%溶壁酶＋0.5%崩溃酶的混合酶系、酶解温度为30 ℃、菌龄为8 d、蔗糖为酶解渗透压稳定剂、酶解时间为3 h的条件下,桑黄菌原生质体分离产量较高,但兼顾菌丝量和原生质体的再生,较适宜的菌龄为10 d,较适宜的酶解渗透压稳定剂是甘露醇。另外用甘露醇作为培养基渗透压稳定剂、用加桑枝的马铃薯葡萄糖再生培养基进行再生,桑黄菌原生质体再生率较高。结论：在综合考虑桑黄菌原生质体的产量与再生的前提下,获得了使桑黄菌原生质体产量与再生率均较高的试验条件。     

Inhibitory effect of oral intake of natural <Emphasis Type="Italic">Phellinus linteus</Emphasis> fruit body on growth and pulmonary metastasis of B16/BL6 melanoma

In the present study, the immunotherapeutic activity of oral intake of natural Phellinus linteus fruit body (nPF) against growth and pulmonary metastasis of injected B16/BL6 melanoma cells has been examined. The nPF powder was orally administered to B16/BL6-bearing mice, a model for the pulmonary metastasis of melanoma, at doses of 83, 415 and 2,075 mg/kg day in their diet. The dietary intake of nPF powder significantly prolonged the survival time of the B16/BL6-bearing mice. Furthermore, ingestion of nPF dose-dependently enhanced NO production by macrophages prepared from the tumor-bearing, nPF-treated animals. Simultaneously, nPF did not induce direct cytotoxicity against B16/BL6. These results suggest that the oral intake of nPF powder may be useful in immunochemotherapy for cancer because of its life prolongation through the inhibitory effect on growth and metastasis of cancer.     

忍冬木层孔菌子实体29种微量元素分析

目的：分析忍冬木层孔菌子实体微量元素含量,为忍冬木层孔菌用药安全提供依据。方法用电感耦合等离子体质谱仪测定忍冬木层孔菌子实体及其寄主水马桑中29种微量元素的含量。结果忍冬木层孔菌子实体中重金属元素Pb含量为3.36μg/g,Cu含量为9.68μg/g,As含量为1.38μg/g,Cd未检出。忍冬木层孔菌子实体中微量元素与寄主水马桑中微量元素基本成正相关。结论忍冬木层孔菌子实体中Pb〈5μg/g、Cu〈20μg/g、As〈2.0μg/g、Cd〈0.3μg/g,符合药用植物及制剂进出口绿色行业标准的限量标准。     

桑黄多糖对小鼠骨髓细胞微核和染色体的影响

目的通过小鼠细胞染色体畸变和微核试验,探讨桑黄多糖对小鼠骨髓细胞的遗传毒性。方法试验设3个剂量组为2.5g·kg-1、5.0g·kg-1、10.0g·kg-1BW,经口灌胃进行试验,取小鼠骨髓制备骨髓细胞标本,分别观察并计算各剂量组小鼠的染色体畸变率和微核率。结果桑黄多糖各剂量组小鼠骨髓细胞染色体畸变率和微核率与空白对照均无显著性差异（P〉0.05）,而阳性对照组环磷酰胺与空白对照组比较有显著性差异（P〈0.01）。结论桑黄多糖各剂量组对小鼠骨髓细胞染色体和微核均无影响。     

Antiplatelet activity of Phellinus baummii methanol extract is mediated by cyclic AMP elevation and inhibition of collagen-activated integrin-α(IIb) β₃ and MAP kinase

Phellinus baumii is a mushroom that has been used as folk medicine against various diseases and is reported to have antidiabetic, anticancer, antioxidant, antiinflammatory and antihypertensive activities. However, information on the effects of P. baumii extract in platelet function is limited. Therefore, the aim of this study was to examine the impact of a P. baumii methanol extract (PBME) on platelet activation and to investigate the mechanism behind its antiplatelet activity. PBME effects on agonist‐induced platelet aggregation, granule secretion, [Ca²⁺]_i mobilization, α_IIbβ₃ activation, cyclic AMP release and mitogen‐activated protein kinase (MAPK) phosphorylations were studied using rat platelets. PBME dose‐dependently inhibited collagen, thrombin and ADP‐induced platelet aggregation with an IC₅₀ of 51.0 ± 2.4, 54.0 ± 2.1 and 53.0 ± 4.3 μg/mL, respectively. Likewise, thrombin‐induced [Ca²⁺]_i and collagen‐activated ATP secretions were suppressed in PBME treated platelets. Aggregation and ATP secretion were also markedly attenuated by PBME alone or in combination with PP2 (Src inhibitor) and U‐73122 (PLC inhibitor) in collagen‐stimulated platelets. Besides, PBME treatment elevated basal cyclic AMP levels and inhibited collagen‐induced integrin‐α_IIbβ₃ activation. Moreover, PBME attenuated extracellular‐signal‐regulated protein kinase 2 (ERK2) and c‐Jun N‐terminal kinase 1 (JNK1) phosphorylations. Further PD98059 (ERK inhibitor) and SP60025 (JNK inhibitor) reduced collagen‐induced platelet aggregation and ATP secretion. In conclusion, the observed PBME antiplatelet activity may be mediated by activation of cyclic AMP and inhibition of ERK2 and JNK1 phosphorylations. Finally, these data suggest that PBME may have therapeutic potential for the treatment of cardiovascular diseases that involve aberrant platelet function. Copyright © 2011 John Wiley & Sons, Ltd.     

Phellinus linteus Extract Augments the Immune Response in Mitomycin C-Induced Immunodeficient Mice

Phellinus linteus is a fungus distributed throughout Japan, Korea and China. Boiled water-soluble extracts from P. linteus (PLW) have shown anti-tumor and immunomodulatory properties in experiments done by intraperitoneal treatment, or in in vitro cell cultures. This is the first investigation on how oral administration of PLW influences immune responses. Here, we established immunodeficient mice by mitomycin C (MMC) and then researched how PLW influenced plaque-forming cell (PFC) production and populations of cytokine [interferon- (IFNgamma-) and interleukin-4 (IL-4)]-producing T lymphocytes. PLW samples were administered orally for 19 days (1, 2 or 4 g/kg/day). PFC assay was followed using Jerne's method. IFN- and IL-4-producing T lymphocyte populations were measured by flow-activated cell sorter (FACS). These assays were conducted the day after the last oral administration. MMC groups were given MMC (1 mg/kg/day) intraperitoneally for 6 days with PLW administration. The number of PFC per 10(6) spleen cells increased significantly in the PLW (2 g/kg/day) group when compared with the MMC-control (P < 0.05) while populations of IFNgamma- and IL-4-producing T lymphocytes decreased by MMC treatment. However, the PLW group tended to increase more than the MMC-control. Our results indicated that PLW augments the immune response of the spleen in MMC-induced immunodeficient mice.     

Protective effects of Phellinus linteus extract against iron overload-mediated oxidative stress in cultured rat hepatocytes

Phellinus linteus (PL) mushroom has been reported to possess antioxidant activity. The present study was designed to investigate whether an ethanol extract obtained from PL might ameliorate oxidative stress and enhance antioxidant enzyme activities in primary rat hepatocytes, which were overloaded with iron using ferric nitrilotriacetate (FeNTA) complex. FeNTA enables hepatocytes to accumulate substantially redox-active iron and stimulates the production of injurious hydroxyl radicals, which in turn, initiate oxidative stress-mediated cytotoxicity. The results showed that pretreatment of hepatocytes with PL extract (50, 100 and 200 microg/mL) for 24 h significantly reversed FeNTA-induced cell viability loss, lactate dehydrogenase leakage (LDH), lipid peroxidation (LPO) and protein carbonyl formation in a dose-dependent manner. It was further observed that PL extract produced an inhibitory effect on intracellular reactive oxygen species (ROS) formation caused by FeNTA. Concomitantly, the amount of GSH content and the activities of glutathione reductase (GSH Rd) and glutathione peroxidase (GSH Px) in hepatocytes pretreated with PL extract increased substantially compared with those treated with FeNTA alone. These results suggest that PL may be useful in protecting against FeNTA-induced oxidative damage and also be capable of attenuating cytotoxicity of other oxidants.     

大孔吸附树脂纯化桑黄总黄酮工艺

目的研究大孔树脂纯化桑黄总黄酮的工艺。方法考察3种大孔树脂对桑黄总黄酮的静态饱和吸附量和解吸率,选择合适的树脂类型,并优化其纯化工艺。结果 AB-8大孔树脂对桑黄总黄酮的吸附容量大,洗脱率高,其最佳纯化工艺:50 g树脂湿法装柱(φ2.4 cm,300 mm,径高比1∶10),5 mg/mL粗提物溶液100mL上柱,1柱体积(BV)水洗,继以5 BV的70%乙醇洗脱,流速2 BV/h,洗脱液浓缩干燥,得精制桑黄总黄酮,含量707.2 mg/g,得率为65.31%。结论 AB-8大孔树脂可以较好地纯化富集桑黄总黄酮。