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31.
Three new lanostane triterpene acids, 3‐O‐acetylganoderic acid B ( 1 ), 8β,9α‐dihydroganoderic acid C ( 3 ), and 3‐O‐acetylganoderic acid K ( 4 ), as well as two new lanostane triterpene acid ethyl esters, ethyl 3‐O‐acetylganoderate B ( 2 ) and ethyl ganoderate J ( 5 ), were isolated and characterized from Ganoderma lucidum mycelia which was cultured by submerged fermentation method. Their structures were elucidated on the basis of spectroscopic methods. In addition, the identification of two known lanostane triterpene acid methyl esters, methyl O‐acetyl ganoderate C and methyl 3,7,11,15,23‐pentaoxo‐lanost‐8‐en‐26‐oate were identified by comparison of the NMR data with those reported in the literature.  相似文献   
32.
One new lignan derivative 2,3-dimethyl-4-(4′-hydroxy-3′,5′-dimethoxyphenyl)-6-hydroxy-7-methoxy-naphthalene (1), together with four known analogues (2-5), were isolated from acetone extract of the fruiting bodies of Ganoderma lipsiense collected in the Hainan Province, China. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. Compound 1 showed insecticidal activity against newly hatched karvae of Helicoverpa armigera Hubner. Compounds 1-5 showed moderate antibacterial activity against Staphylococcus aureus with the same MIC value of 1.25?μg/mL.  相似文献   
33.
建立了基于傅立叶变换离子回旋共振超高分辨质谱(FTICR-MS)的赤灵芝化学成分鉴定和指纹图谱分析方法,并应用于不同产地赤灵芝样品的来源区分。样品采用50%甲醇进行回流提取后,以流动注射的进样方式进行直接质谱分析。以ESI离子源在负离子模式下进行检测,质荷比扫描范围为100~1 000 Da。采用精确分子量测定和碰撞诱导解离实验进行化学成分鉴定,通过与文献进行比对,共鉴定出63种化学成分(1种萜烯醛、3种糖、4种三萜醇、6种有机酸和49种三萜酸类成分)。采用聚类分析和主成分分析(PCA)对所获得的质谱指纹图谱进行统计学分析,在95%的置信区间下,多个批次不同产地的赤灵芝样品得到了较好的来源区分。研究结果表明该方法可实现赤灵芝的直接、快速、高效分析和指纹图谱研究,在中药分析领域有着广阔的应用前景。  相似文献   
34.
采用激光拉曼光谱分析比较了灵芝孢子油、橄榄油、葵花籽油及鱼肝油的光谱特征,结果显示激光拉曼光谱法可以用于快速检测灵芝孢子油:灵芝孢子油具有位于1 563 cm-1处峰强较弱线宽较宽的特征拉曼峰,而且位于1 445和1 660 cm-1两处拉曼峰的相对强度比与其他油不同。同时运用激光拉曼光谱法分析了变质的灵芝孢子油和廉价的灵芝孢子油,发现暴露在空气中一段时间后的灵芝孢子油的活性成分基本被氧化了,市场上廉价的灵芝孢子油可能是由变质的灵芝孢子油、葵花籽油、或其他廉价植物油混合掺杂而成的。  相似文献   
35.
In submerged culture of Ganoderma lucidum, the pH optimum for cell growth has been shown to be lower than that for exopolysaccharides (EPS) formation. Therefore, in the present study, a two-stage pH-control strategy was employed to maximize the productions of mycelial biomass and EPS. When compared, a batch culture without pH control had a maximum concentration of EPS and endopolysaccharides, which was much lower than those with pH control. Maximum mycelial growth (12.5 g/L) and EPS production (4.7 g/L) were achieved by shifting the controlled pH from 3.0 to 6.0 after day 4. The contrast between the controlled-pH process and uncontrolled pH was marked. By using various two-stage culture processes, it was also observed that culture pH has a significant affect on the yield of product, mycelial morphology, chemical composition, and molecular weight of EPS. A detailed observation of mycelial morphology revealed that the productive morphological form for EPS production was a dispersed pellet (controlled pH shifting from 3.0 to 6.0) rather than a compact pellet with a dense core area (controlled pH 4.5) or a feather-like pellet (controlled pH shifting from 6.0 to 3.0). Three different polysaccharides were obtained from each pH conditions, and their molecular weights and chemical compositions were significantly different.  相似文献   
36.
粤北灵芝的红外光谱宏观三级鉴定研究   总被引:1,自引:0,他引:1  
采用红外光谱的宏观三级鉴定法分析鉴别了赤芝、黑芝、松杉灵芝和树舌灵芝。在一维红外光谱中,根据灵芝的1 153和1 078 cm-1的糖苷类化合物的吸收峰的相对强度,可得出这4种灵芝的糖苷类化合物的相对含量依次为: 赤芝>黑芝>松杉灵芝>树舌灵芝。在高分辨率二阶导数谱中,四者在1 600~1 720 cm-1波段处的吸收峰的峰位置、峰形状均有很大差别,说明四者本身所含的氨基酸多肽类物质是不一致的。观测二维相关红外光谱,四者都存在1 100 cm-1的糖苷类化合物的自动峰,不同的是赤芝共有4个自动峰且1 040 cm-1自动峰强度最大,黑芝共有5个自动峰且1 040和1 139 cm-1自动峰的强度最大,松杉灵芝共有4个自动峰且1 140 cm-1的自动峰强度最大,树舌灵芝共有5个自动峰且1 134 cm-1的自动峰强度最大。谱图的三级鉴定验证了赤芝、黑芝、松杉灵芝和树舌灵芝在糖苷类化合物和氨基酸多肽类化合物的相对含量上都是不一致的。结果表明,运用红外光谱法可以快速有效地分析和鉴定赤芝、黑芝、松杉灵芝和树舌灵芝。  相似文献   
37.
用豆油作为氧载体加入发酵液中形成双液相发酵体系,以改善灵芝胞外多糖的发酵状况.实验表明:常见的氧载体材料在双液相发酵过程中不为灵芝菌体所利用,仅起到促进溶氧的效果;在灵芝胞外多糖的双液相发酵体系中,KLa值明显提高,溶氧水平(DO)有显著改善,发酵液的运动黏度μ有所降低,有助于降低搅拌能耗;氧载体改善了质量传递,提高了细胞的代谢水平,使胞外多糖的产量提高了44%,发酵周期缩短了约17%.说明双液相发酵体系对灵芝胞外多糖发酵是一种新型有效的途径.  相似文献   
38.
Three new lanostanoid triterpenes named 3beta,7beta-di- hydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oic acid (1), 3beta,7beta-dihydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oic acid methyl ester (2), and 12beta-acetoxy-3beta,7beta-dihydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oic acid (3) were isolated from the fruit bodies of Ganoderma lucidum. They all show a Delta(16, 17) double bond unprecedented in such types of lanostanoid triterpenes possessing the side chain at C-17. The complete NMR assignments for these compounds were carried out using (1)H, (13)C, DEPT, COSY, HSQC, HMBC, and ROESY NMR experiments.  相似文献   
39.
Lucidenic acid A ( 1 ) and a new lactone, lucidenolactone ( 2 ) were isolated from the fruiting bodies of Ganoderma lucidum. Their structures were elucidated by spectroscopic method and single-crystal X-ray analysis. Lucidenolactone ( 2 ) showed significant antiplatelet aggregation activity. The NMR spectral data of lucidenic acid A were also reassigned.  相似文献   
40.
The methanolic extract of fruit bodies of cultivated Ganoderma lucidum was separated by silica gel column chromatography and preparative thin-layer chromatography to give ten compounds. On the basis of spectral analysis, chemical procedures and gas chromatography, d-mannitol (1), ergosta-7, 22-dien-3β-yl palmitate (2), ergosterol (3), ergosta-7, 22-dien-3β-ol (4), 5α-lanosta-7,9(11),24-trien-3β,26-diol (5), ergosterol peroxide (6), 24,25,26-trihydroxy-5α-lanosta-7,9(11)-dien-3-one (7), 5α-lanosta-7,9(11)-dien-3β,24,25,26-tetraol (8) and 8,9-epoxyergosta-5,22-dien-3β,15-diol (9) were identified. Among these compounds, 8,9-epoxyergosta-5,22-dien-3β,15-diol was first separated from Ganoderma lucidum.  相似文献   
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