5-氮杂胞苷对桦褐孔菌多酚积累的影响

本文旨在研究DNA甲基转移酶抑制剂5-氮杂胞苷对桦褐孔菌多酚合成的调控。以液体摇瓶法培养桦褐孔菌,并在培养液中添加5-氮杂胞苷。采用荧光定量PCR测定与多酚合成相关的编码苯丙氨酸解氨酶（pal）、4-香豆酸辅酶A连接酶（4cl）和硬毛素合成酶（sps）基因表达水平,染色质免疫沉淀技术对编码硬毛素合成酶基因启动子区的组蛋白甲基化修饰进行检测,Folin-Ciocalteu法测定桦褐孔菌细胞内和发酵液中多酚的含量。结果显示,5-氮杂胞苷的添加提高了桦褐孔菌体内pal、4cl和sps基因的表达水平,改变了sps启动子区的组蛋白甲基化修饰,即降低了H3K9三甲基化修饰水平,提高了H3K4和H3K36三甲基化修饰水平,显著提高了桦褐孔菌细胞内和发酵液中多酚的积累量。5-氮杂胞苷诱导下桦褐孔菌细胞内多酚积累量达(46.6±2.8)mg/g,明显高于对照组多酚积累量(28.7±1.0)mg/g,并且胞外多酚的含量由对照组的(66.9±1.3)mg/L提高至(92.3±2.3)mg/L。此外,经5-氮杂胞苷处理后胞内多酚清除DPPH自由基、超氧阴离子和羟自由基的能力显著提高。可见,5-氮杂胞苷可以作为调节因子激发桦褐孔菌液体培养条件下多酚的合成,可以成为进一步提高桦褐孔菌液体发酵产物中多酚产量的技术手段之一。     

真菌激发子对桦褐孔菌多酚积累的影响

作者旨在阐明真菌激发子对桦褐孔菌多酚积累的影响。以摇瓶法培养桦褐孔菌,在其培养液中加入真菌激发子和一氧化氮合酶抑制剂氨基胍,观察桦褐孔菌多酚和一氧化氮的积累并测定菌丝体内一氧化氮合酶和苯丙氨酸解氨酶的活性。多酚以Folin-Ciocalteu法测定,一氧化氮的积累量用硝酸还原酶法测定,一氧化氮合酶和苯丙氨酸解氨酶活性均以分光光度计法测定。结果表明,添加45μg/mL的激发子可使桦褐孔菌菌丝体多酚的积累量达到46.5mg/g,显著地高于正常培养的菌丝体多酚积累量34.6mg/g;同时加入45μg/mL的激发子和10mmol/L氨基胍则使菌丝体多酚积累的最高水平降为34.8mg/g。此外,激发子的加入显著促进了一氧化氮的产生并提高了苯丙氨酸解氨酶活性,而这种促进和提升作用为氨基胍所抑制。这表明真菌激发子能显著地提升桦褐孔菌多酚类化合物的积累,而一氧化氮可能是这种提升作用的信号传导分子。     

Folin-Ciocalteu比色法测定花椒中多酚含量的研究

研究了以没食子酸为标准品,采用Folin-Ciocalteu比色法,测定花椒多酚含量的适宜条件。结果表明:当Folin-Ciocalteu试剂与10%Na2CO3溶液之比为1∶2(V∶V),Folin-Ciocalteu试剂体积为4 mL,反应温度为25℃,反应时间为120 min时,多酚含量在1~6μg/mL范围内与吸光值呈良好的线性关系。测定了4种花椒中的多酚含量,四川青花椒多酚含量最高。     

桦褐孔菌三萜类物质的提取与含量测定

以桦褐孔菌发酵菌丝体为材料,通过对溶剂乙醇（95%）、甲醇、乙酸乙酯、丙酮、异丙醇、正己烷和氯仿的提取效果比较表明,提取三萜类化合物的最佳溶剂为异丙醇,提取时间为24h,每个样品所需溶剂量（6mL）和菌丝体样品量（100mg）较少,并可同时对大量样品进行有效提取。以白桦脂醇为标准品,对香草醛-冰醋酸-高氯酸分光光度法进行评价,证明该方法简单快速、准确度高、试验误差小、重复性好。利用此方法对桦褐孔菌的野生菌核和发酵菌丝体内三萜类化合物含量进行测定,结果表明野生菌核（59.86mg/g）和发酵菌丝体（94.92mg/g）中都含有很高的三萜类化合物,且发酵菌丝体中三萜类化合物含量高于野生菌核。因此在桦褐孔菌产品开发中,发酵菌丝体可代替野生菌核进行大工业化生产。     

Folin-Ciocalteu分光光度法测定夏枯草总酚含量的研究(英文)

通过采用Folin-Ciocalteu试剂,以没食子酸为对照品,用紫外可见分光光度法,研究测定夏枯草中总酚含量。结果表明,在装有样品的10 mL容量瓶中依次加入Folin-Ciocalteu试剂0.5 mL,20%Na2CO31.7 mL,室温放置60 min后,在波长660 nm或760 nm测定吸光度。多酚质量浓度在0～10.3μg/mL范围内与吸光度有良好的线性关系,回归方程在660 nm为Y=94.542X-0.0067,R2=0.9999,加样回收率为101.7～105.0%;760 nm为Y=101.13X-0.0191,R2=0.9990,加样回收率为105.1～107.6%。本研究在稳定性、准确性和重复性方面都具有较好的实验结果,可为夏枯草多酚的定量分析提供方法参考。     

激发子对桦褐孔菌多酚合成的诱导及其生化机制初探

旨在研究真菌激发子对桦褐孔菌多酚合成的影响,采用液体摇瓶培养方式,将真菌激发子加入到桦褐孔菌液体培养物中,检测桦褐孔菌次级代谢产物的积累,以及真菌激发子对桦褐孔菌一氧化氮合酶(NOS)活性的影响。结果表明,适量添加真菌激发子能够提高桦褐孔菌的代谢速率,提高多酚类化合物的合成,胞内和胞外多酚最高可达102.15 mg/L和311.91 mg/L,并能显著提高桦褐孔菌NOS的活性,其活性最高可达151.93 U/mg prot,发酵液一氧化氮(NO)含量最高可达256.28μmol/L。这表明,真菌激发子能够有效激活桦褐孔菌的次级代谢产物合成途径。     

双水相超声法提取桦褐孔菌三萜

通过单因素实验和正交实验对影响桦褐孔菌三萜提取的异丙醇体积浓度、硫酸铵质量浓度、料液比和超声时间等因素进行探讨,旨在建立桦褐孔菌Inonotus obliquus菌丝体三萜类化合物的提取工艺。结果表明,提取桦褐孔菌三萜的最佳条件为：异丙醇体积浓度40%,硫酸铵质量浓度0.125g/mL,料液比（W/V）0.9:1,超声时间为35min,三萜提取率为6.18%,提取效率明显高于常规超声波提取法（5.38%）。利用该方法获得的三萜具有较强清除自由基的能力。通过正交实验获得的桦褐孔菌三萜的提取工艺是一种经济、有效的方法。     

Folin-Ciocalteu比色法测定铜藻中褐藻多酚含量的研究

以没食子酸为标准品,使用福林酚(Folin-Ciocalteu)试剂,通过紫外-可见分光光度法,对铜藻中褐藻多酚的含量进行了测定。结果表明,测定波长为760 nm,显色试剂Folin-Ciocalteu的用量为1.25 m L,0.1 g/m L Na2CO3溶液用量为4.0 m L,定容至10 m L,显色温度为30℃,反应时间为60 min,多酚含量在15~50μg/m L范围内与吸光度呈良好线性关系,回归方程为Y=0.0138X+0.0267,R2=0.9993。本测定方法的平均回收率为96.18%,相对标准偏差(RSD)为2.44%。该方法的稳定性、重现性、精密度以及加标回收率的相对标准偏差均符合要求,可用于铜藻中褐藻多酚含量的测定。按照本方法测定铜藻中褐藻多酚的平均含量为17.36 mg/g(RSD=1.25%)。     

Folin-ciocalteu比色法测桑叶中多酚含量

采用以没食子酸为标准,研究了Folin-ciocalteu比色法测定桑叶中多酚含量的适宜条件。结果表明,桑叶提取液在Folin-ciocalteu试剂2.0 mL、20%Na2CO3溶液5.0 mL、反应温度30℃、反应时间2 h的条件下,测定其760 nm处的吸光值,多酚浓度在10.0～100.0 mg/L范围内与吸光值呈良好的线性关系;稳定性、精密度、重现性和回收率实验的相对标准偏差为0.2969%～2.502%。该法是一种简便、快速、准确测定桑叶多酚含量的可靠方法。     

桦褐孔菌与松口蘑菌粉降血糖作用的研究

为评价桦褐孔菌和松口蘑发酵菌粉的降血糖作用,本文观察了经不同浓度桦褐孔菌和松口蘑菌粉溶液灌胃后,小鼠正常血糖、给予葡萄糖小鼠以及四氧嘧啶糖尿病小鼠血糖的变化.结果表明:桦褐孔菌、松口蘑菌粉溶液(500、1000 mg/kg)对小鼠正常血糖值、正常小鼠糖耐量没有明显影响(P>0.05);对于糖尿病小鼠血糖,桦褐孔菌低剂量组(500 mg/kg)和桦褐孔菌高剂量组(1000 mg/kg)的降糖效果较为明显(P<0.01),用药前与用药后第21 d的血糖值分别为(14.94±1.85)、(10.43±2.22)和(14.89±1.65)、(10.17±2.14) mmol/L,降糖率分别为30.23% 和31.7%.桦褐孔菌和松口蘑菌粉对于小鼠正常血糖、正常小鼠糖耐量无明显影响,对于四氧嘧啶糖尿病小鼠具有一定的降血糖效果.     

桦褐孔菌三萜类物质的提取与含量测定

以桦褐孔菌发酵菌丝体为材料,通过对溶剂乙醇(95%)、甲醇、乙酸乙酯、丙酮、异丙醇、正己烷和氯仿的提取效果比较表明,提取三萜类化合物的最佳溶剂为异丙醇,提取时间为24h,每个样品所需溶剂量(6mL)和菌丝体样品量(100mg)较少,并可同时对大量样品进行有效提取。以白桦脂醇为标准品,对香草醛-冰醋酸-高氯酸分光光度法进行评价,证明该方法简单快速、准确度高、试验误差小、重复性好。利用此方法对桦褐孔菌的野生菌核和发酵菌丝体内三萜类化合物含量进行测定,结果表明野生菌核(59.86mg/g)和发酵菌丝体(94.92mg/g)中都含有很高的三萜类化合物,且发酵菌丝体中三萜类化合物含量高于野生菌核。因此在桦褐孔菌产品开发中,发酵菌丝体可代替野生菌核进行大工业化生产。     

Metabolomics Profiling of Tunisian Sonchus oleraceus L. Extracts and Their Antioxidant Activities

Sonchus oleraceus (L.) L. (Asteraceae) is an edible wild plant, known for its uses in traditional medicine. The aim of this study is to explore the phytochemical composition of the aerial parts (AP) and roots (R) of aqueous extracts of Sonchus oleraceus L. growing in Tunisia, using liquid chromatography-tandem mass spectrometry(LC/MS/MS), and determine the content of polyphenols and antioxidant activities. Results showed that aqueous extracts of AP and R contained, respectively, 195.25±33 μg/g and 118.66±14 μg/g gallic acid equivalent (GAE), and 52.58±7 μg/g and 3.2±0.3μg/g quercetin equivalent. AP and R extracts also contained tannins, 581.78±33 μg/g and 948.44±19 μg/g GAE. The AP extract in the 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activities, hydroxyl radical scavenging (OH−) and in cupric reducing antioxidant activity (CUPRAC) assays were respectively 0.325±0.036 mg/mL, 0.053±0.018 mg/mL, 0.696±0.031 mg/mL and 60.94±0.004 μMTE/g, while the R extract using the same assays showed, 0.209±0.052 mg/mL, 0.034±0.002 mg/mL, 0.444±0.014 mg/mL and 50.63±0.006 μM Trolox equivalent/g, respectively. A total of 68 compounds were tentatively identified by LC/MS/MS in both extracts in which quinic acid, pyrogallol, osthrutin, piperine, gentisic acid, fisetin, luteolin, caffeic acid, gingerol, were the most abundant in the LC/MS/MS spectrum. Many of these metabolites were found for the first time in Tunisian Sonchus oleraceus L. which may take account for the antioxidant activities exhibited by the plant.     

Polyphenols of Rosa L. leaves extracts and their radical scavenging activity

Antioxidant potential of Rosa L. leaves methanolic extracts was evaluated in vitro using a spectrophotometric method based on measuring the radical scavenging effect on 2,2-di-phenyl-1-picrylhydrazyl (DPPH) radicals. The contents of ellagic acid, quercetin and kaempferol in the extracts from leaves of seventeen rose species were determined using SPE-RP-HPLC methods. Additionally, total phenolic content was determined spectrophotometrically according to the Folin-Ciocalteu procedure and calculated as gallic acid equivalents (GAE). Remarkable high antioxidant activity and high total phenolic content (5.7% < GAE < 15.2%), large ellagic acid (EA) content from 9.37 to 19.42 mg/g of dry weight, a quercetin content ranging from 3.68 to 15.81 mg/g of dry weight and kaempferol content from 1.25 to 9.41mg/g of dry weight were found in rose leaves. Significant correlation between EA (r(2) = 0.6131), quercetin (r(2) = 0.5158), total phenolic content (r(2)= 0.8485) and antioxidant activity was observed. Basing on the studies conducted one may assume that the extracts of rose leaves are a rich source of natural antioxidants and could be used to prevent free-radical-induced deleterious effects.     

矿质营养与其他生长物质对荷叶离褶伞菌丝生长的影响

1mg/mLKCl促进荷叶离褶伞菌丝生长;5或10mg/mLNaCl、5或10mg/mLMgSO4、5或10mg/mLKCl、10mg/mLH2PO4和1mg/mLCaSO4抑制菌丝生长;0.8mg/mL的MnSO4和CuSO4以及0.5mg/mLFeSO4、0.2或0.5mg/mLCoCl2和0.2、0.5或0.8mg/mLZnSO4促进菌丝生长;0.5或0.2mg/mLCuSO4、0.2或0.5mg/mLMnSO4及0.8或0.2mg/mLFeSO4对菌丝生长的影响不显著;维生素B6、维生素C、维生素PP和维生素B1可促进菌丝生长,在含有10μg/L维生素B6的培养基上菌丝生长速度最快,但维生素C试用浓度较低(50μg/L)时对菌丝生长的影响不显著;吲哚丁酸、吲哚乙酸、奈乙酸对菌丝生长具有促进作用,但0.1、0.5或1.0μg/L赤霉素对菌丝生长的影响不显著。     

Date Seeds (Phoenix dactylifera): Antioxidant Potential and Profile of Free and Bound Polyphenols from Different Cultivars

In this study, the antioxidant activities and detailed phenolic profiling of extracts from seven cultivars of date seeds were investigated. Significant differences were detected among cultivars. Total phenolic content (TP) ranged between 135.9±12.1 and 284.86±21.9 mg GAE/g DM. The total flavonoid value varied between 34.20±0.34 and 94.46±1.04 mg RE/g DM. The condensed tannin ranged from 24.17±1.13 to 201.60±9.95 mg CTE/g DM. Phloroglucinolysis was used to depolymerize the bound polyphenols. Results show the presence of phenolic acids: Hydroxybenzoic acid, hydroxycinnamic acid, and a high amount of flavan-3ols (monomers, dimers, and trimers). Before depolymerization, the highest amount of total polyphenols was identified in Kenta (8.48 g/kg) and the lowest was detected in Hessa (4.74 g/kg). After depolymerization, the flavan-3-ols increased significantly, ranging between 46.91g/kg in Hessa and 72.38 g/kg in Deglet Nour, with a high degree of polymerization (DP) in all cultivars. It can be concluded that date seeds represent a good source of bioactive compounds.     

氨基酸和霉菌水提物对深层发酵桦褐孔菌菌丝体黄酮积累及其抗氧化活性的影响

黄酮类化合物是桦褐孔菌菌丝体中多酚类化合物的重要组成部分,也是该菌治疗众多疾病的有效成分之一。然而人工培养桦褐孔菌黄酮等酚类化合物积累甚少,导致药理活性的明显下降。为此,我们研究了3种氨基酸和4种霉菌水提物对深层发酵桦褐孔菌黄酮的积累及其抗氧化能力的影响。在所试验的3种氨基酸和4种霉菌水提物中,L-酪氨酸,黄曲霉和毛霉水提物能有效地增加该菌黄酮的积累。人工培养菌体中的黄酮至少由4种黄酮苷组成,苷元分别是槲皮素、柚皮素、山奈酚和异鼠李素。深层发酵菌丝体具有一定的抗氧化能力,并与总黄酮的含量呈正相关。由L-酪氨酸,黄曲霉和毛霉水提物调控生长的桦褐孔菌菌丝体,能有效地清除超氧阴离子、羟基自由基和DPPH自由基。