沙苑子的化学成分和药理作用

沙苑子主要含有黄酮类、三萜类、有机酸类、氨基酸、多肽、蛋白质、鞣质、甾醇、微量元素等。具有改善血液流变学指标、降低血压、调节血脂、抑制血小板聚集、保护肝脏、增强免疫功能、抗炎、镇痛及调节中枢神经系统等作用。     

沙苑子的保健功效与药膳

对我国传统中草药沙苑子的植物形态及分布,历代本草利用,化学成分,药理、毒理作用和保健药膳进行了论述.     

以沙苑子苷为对照品测定沙苑子总黄酮含量

目的 :以沙苑子苷为对照品测定沙苑子总黄酮含量。方法 :80 %乙醇提取液 ,2 6 6nm测定紫外吸收度。结果 :总黄酮含量为 2 1.5mg/g ,RSD =1.0 0 % ;回收率 95 .4 % ,RSD =2 .2 7% ,线性范围 4～ 2 4ug/ml。结论 :本法测定沙苑子总黄酮含量 ,操作简便 ,稳定性好 ,可用于沙苑子的质量控制。     

樟子松乙醇提取物体外抗氧化活性研究

测定了樟子松球果、树皮、树叶、木质部4个部位提取物的总抗氧化能力、总还原力、二苯代苦味酰基（DPPH·）清除能力、羟基自由基（·OH）清除能力、超氧阴离子（O^·₂）清除能力5个指标,并以抗坏血酸（Vc）为阳性对照评价从樟子松4个部位提取的松多酚体外抗氧化活性。结果表明：（1）从樟子松树皮中提取的樟子松多酚表现出较强的抗氧化能力,在较高浓度下与抗氧化剂（Vc）相差较小;从樟子松球果中提取的樟子松多酚也表现出较强的还原力,甚至超过阳性对照抗氧化剂Vc;（2）从樟子松树皮中提取的樟子松多酚在二苯代苦味酰基（DPPH·）清除能力、羟基自由基（·OH）清除能力上均为三者之中最高的,但都不超过抗氧化剂（Vc）的抗氧化能;（3）超氧阴离子（O^·₂）清除能力。三者的清除率均为负值,说明该方法测定超氧阴离子（O^·₂）清除率存在干扰因素,无法比较三者在这一指标上的能力大小。上述结果表明樟子松乙醇提取物具有较强的抗氧化能力,可作为天然的抗氧化剂。     

固相小柱对沙苑子总黄酮萃取方法的研究

目的:以沙苑子总黄酮为研究对象,考察固相萃取小柱的洗脱条件,确定固相萃取沙苑子总黄酮的实验方法。方法:以不同浓度的甲醇对不同填料的固相小柱进行洗脱,将洗脱液在岛津VP-ODS(150 mm×4.6 mm,5μm)柱上进行高效液相色谱分析。通过比较不同浓度及体积甲醇的萃取效率,确定沙苑子苷在固相萃取小柱上的洗脱条件。结果:用正相氨基小柱以50%甲醇洗脱效果好,回收率可达100%。结论:经试验,正相氨基小柱对沙苑子苷的萃取回收率约为100%,适用于沙苑子总黄酮中沙苑子苷的分析。     

凤仙花不同部位乙醇提取物多酚、黄酮含量测定及抗氧化活性研究

采用55%的乙醇分别回流提取凤仙花的茎、叶、花中的活性物质,采用比色法测定各部位的多酚及总黄酮含量,测定各提取物对DPPH、羟自由基、超氧阴离子自由基的清除能力和还原力等抗氧化活性指标。结果表明,凤仙花各部位的多酚(以没食子酸计)、总黄酮(以芦丁计)含量由高到低依次为凤仙花的叶、花、茎,多酚含量分别为72.81、66.07、33.07 mg/m L,总黄酮含量分别为112.13、108.06、30.62 mg/m L。各种提取物均有不同程度的抗氧化活性,且抗氧化活性与提取物浓度存在量效关系,其中叶提取物清除DPPH自由基、羟自由基、超氧阴离子自由基活性以及还原力均最高,本研究为凤仙花作为低毒高效的天然抗氧化剂应用提供了依据。     

加拿大一枝黄花提取物的抗氧化活性研究

为进一步开发和利用加拿大一枝黄花(Solidago canadensis),该研究采用氯化铝显色法和福林酚法测定加拿大一枝黄花乙醇提取物及其不同极性萃取物中的总黄酮和总酚的含量;以抗坏血酸(Vitamin C,Vc)和二丁基羟基甲苯(BHT)为阳性对照,应用2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)、1,1-二苯基苦基苯肼(DPPH)自由基清除体系、铁离子还原能力(FRAP)法和抗氧化能力指数(ORAC)法研究其体外抗氧化活性。结果表明:乙酸乙酯萃取物中的总黄酮(202.45 mg·g~(-1))和总酚(485.94 mg·g~(-1))含量最高,且其抗氧化活性最强,并强于阳性对照Vc(P0.05)。因而,加拿大一枝黄花乙酸乙酯萃取物将有可能成为一种潜在的天然高效抗氧化剂,具有广泛的应用前景。     

沙苑子的组织培养与快速繁殖

以扁茎黄芪的干燥成熟种子沙苑子为材料进行扁茎黄芪的组织培养研究.结果表明:沙苑子的发芽培养基为 MS,扁茎黄芪继代增殖最适培养基为:MS 6-BA3.0 mg/L NAA 0.5 mg/L,平均增殖系数达到 4.5,平均苗高达3.5 cm;生根最适培养基为:1/2MS NAA0.05 mg/L,生根数为4～6条,生根率达到100%.     

印度块菌提取物抗氧化活性的研究

对印度块菌Tuber indicum子实体的提取物,包括55%乙醇粗提物(ECE)、石油醚提取物(PEF)和乙酸乙酯提取物(EAF)的清除DPPH自由基和羟基自由基能力、铁离子鳌合能力以及各提取物的总酚含量等进行了研究和测定,结果显示,3种提取物的清除自由基能力和铁离子鳌合能力具有显著差异(P0.05);ECE对DPPH自由基的清除活性最高,其EC50值为1.61g/L;EAF对羟基自由基及铁离子表现出较强的清除或螯合的能力,其EC50值分别为3.31g/L和0.70g/L;EAF的总酚含量(2.964mg GAE/g提取物)最高,其次是ECE,总酚含量为(2.618mg GAE/g提取物);PEF的清除自由基和铁离子鳌合能力较差,其总酚含量也最低(1.124mg GAE/g提取物);总酚含量与印度块菌提取物清除自由基以及鳌合铁离子的能力密切相关。     

李氏块菌提取物抗氧化活性的研究

对李氏块菌Tuber liyuanum子实体的不同提取物,包括甲醇提取物(ME)、乙醇提取物(EE)、丙酮提取物(AE)、正丁醇提取物(BAE)和乙酸乙酯提取物(EAE),进行清除DPPH自由基、羟基自由基、超氧阴离子自由基、铁离子螯合能力、还原力以及总酚含量的测定和研究,发现ME对DPPH自由基、超氧阴离子自由基清除及还原力活性最高,EC50值分别为23.37mg/m L、11.65mg/m L和24.47mg/m L;EE对羟基自由基清除和铁离子螯合能力活性最高,EC50值分别为7.24mg/m L和小于0.5mg/m L;ME的总酚含量最高(3.08mg GAE/g提取物),其次是EE(1.34mg GAE/g提取物),提取物总酚含量与抗氧化活性呈现出一定的正相关性。     

Enhanced Phenolic Diterpenes Antioxidant Levels Through Non-transgenic Approaches

Plant-derived antioxidants are essential in our diet, and antioxidant composition is a key determinant of the quality of plant extracts of interest to the pharmaceutical and food industries. By using carnosic acid as an example of a key antioxidant constituent of rosemary and sage extracts, we discuss the importance of studying non-transgenic approaches to enhancing antioxidant levels in plants and improving the antioxidant composition of plant extracts. In contrast to other terpenoids or phenolic compounds, carnosic acid has only been found in some Labiatae species, such as rosemary and sage. Carnosic acid has medicinal properties; it is a potent antioxidant and protects skin cells against UV-A radiation and cancer. Furthermore, it has been used as a preservative in food and non-food products, displaying important antimicrobial effects. However, the key steps involved in its biosynthesis remain largely unknown, and thus non-transgenic approaches are required to increase its level in plant extracts. Dried rosemary or sage leaves can contain between 0.1% and 7% carnosic acid, depending on the species and variety, but also on plant growth conditions, sample treatment and mode of extract preparation. Furthermore, leaf age, salinity and ionic interactions can also have a significant effect on biosynthesis and therefore have a strong impact on the total antioxidant potential of rosemary and sage extracts. Non-transgenic approaches, used in these or other species, can significantly increase antioxidant levels and therefore provide very significant improvements in the quality of several botanical extracts used in industry, and can be applied as either an alternative or a complement to transgenic approaches.

Enhanced Phenolic Diterpenes Antioxidant Levels Through Non-transgenic Approaches

All authors

T. Tounekti &; S. Munné-Bosch

https://doi.org/10.1080/07352689.2012.696457

Published online:

26 October 2012

FIG. 1 Chemical structure of synthetic and natural plant-derived antioxidants. Note that the hydroxyl groups in the ortho-position at C₁₁ and C₁₂ of the carnosic acid molecule provide high antioxidant properties (color figure available online).     

12.

固相萃取-高效液相色谱法测定沙苑子苷含量     

牟英  彭少平  顾振纶 《中国野生植物资源》2009,28(3):62-64

目的：建立沙苑子总黄酮中沙苑子苷的含量测定方法。方法：用以氨基为固定相的固相萃取柱对沙苑子总黄酮进行纯化,洗去杂质后的洗脱液进高效液相色谱仪测定。色谱柱为VP—ODS（150mm×4．6mm,5um）,流动相为甲醇：1％HAC溶液（41：59）;流速1．2mL／min;检测波长266nm。结果：沙苑子苷在5—25μg／mL范围内呈良好的线性关系,加样回收率为102．5％,RSD2．3％。结论：本法灵敏、快速、准确,可用于测定沙苑子总黄酮中沙苑子苷的含量。     

13.

沙棘籽提取物抗氧化活性与酚类组成的研究   总被引：10，自引：0，他引：10  

樊金玲  丁霄霖 《天然产物研究与开发》2006,18(4):529-534,554

采用卵磷脂脂质体体系比较了沙棘籽不同溶剂提取物的抗氧化活性,对其中的抗氧化活性成分进行了分析。试验结果表明:当浓度为250μg/mL时,提取物对共轭二烯氢过氧化物的抑制率为0~90.1%,对丙二醛的抑制率为0~88.6%。70%丙酮提取物具有最强的抗氧化活性、清除DPPH自由基能力和还原力。各提取物中主要的酚类物质为原花色素,抗氧化活性与原花色素含量有很好的相关性。     

14.

莲子多糖的结构分析及抗氧化活性     

邓添华  张静  黄达彬  孙润广 《生物加工过程》2012,(6):47-50

用热水浸提、乙醇沉淀、Sevag法除蛋白分离得到水溶性莲子粗多糖。经十六烷基三甲基溴化铵（CTAB）沉淀,硼酸反应以及SephadexG-150层析纯化,得到3种莲子多糖SN1、SN2、SN3。用气相色谱、红外光谱、紫外光谱分析其化学结构。结果表明：SN1主要由葡萄糖、半乳糖组成,含a—D-吡喃葡萄糖环;SN2主链为葡聚糖、并含有其他4种单糖;SN3含7种单糖,并推测是一种酸性氨基多糖或蛋白多糖。体外抗氧化活性实验表明莲子多糖具有一定的清除自由基能力,清除·O2-的能力较强。     

15.

不同炮制方法对玉竹提取物得率及体外抗氧化作用的影响     

王冬梅；吕振江；王永红；张辉辉 《植物研究》2012,32(5):621-626

以多糖、总黄酮、醇溶物和水溶物的得率及体外抗氧化活性为考察指标,研究了酒蒸和蜜蒸两种炮制方法对玉竹品质的影响。结果表明：酒蒸炮制玉竹的多糖、醇溶物得率最高,蜜蒸炮制玉竹总黄酮、水溶物的得率最高,比未炮制的玉竹（生品玉竹）中相应成分的得率分别提高了43.86%、29.53%、49.46%和34.66%。将多糖、水溶性浸出物、醇溶性浸出物及总黄酮四者得率相加的和进行比较,蜜蒸最好,蜜蒸为111.069%,酒蒸为107.309%,生品玉竹为80.926%。酒蒸炮制玉竹的多糖、水溶物对DPPH自由基的清除率均高于蜜蒸玉竹和生品玉竹,其DPPH_IC50分别为0.345±0.019和0.441±0.022 mg·mL^-1;蜜蒸炮制玉竹的总黄酮、醇溶物对DPPH自由基的清除率均高于酒蒸玉竹和生品玉竹,其DPPH_IC50分别为0.047±0.011和0.199±0.036 mg·mL^-1;在浓度为1 mg·mL^-1时,蜜蒸玉竹总黄酮对DPPH自由基的清除率最大,为90.29%,超过了浓度为0.05 mg·mL^-1的芦丁和槲皮素标品对DPPH自由基的清除率。两种炮制方法均提高了多糖、水溶物、总黄酮3种提取物的还原能力,但是降低了醇溶物的还原能力。     

16.

Antioxidant Activities of Some Extracts of Thymus zygis     

《Free radical research》2013,47(5):469-478

The antioxidant activities of methanol and ethyl ether extracts obtained from Thymus zygis, collected during the flowering or non-flowering period, were evaluated and compared. To investigate this potential, extracts were tested on their capacity to react with diphenyl-picrylhydrazyl (DPPH) in a homogeneous medium, and to inhibit Fe²⁺/ascorbate-induced membrane lipid peroxidation, as estimated by the formation of thiobar-bituric acid-reactive substances (TBARS). Although methanol extracts reduce DPPH radicals more efficiently than ethyl ether extracts, suggesting a potent radical scavenger activity, the ethyl ether extracts were found to be most active in inhibiting lipid peroxidation in sarcoplasmic reticulum (SR) membranes. In addition, both extracts present peroxyl and superoxide radical scavenging activities. Peroxyl radicals were generated by the water soluble 2, 2A-azobis(2-amidinopropane) dihydrochloride (AAPH) azoinitiator, and the scavenging activities of the extracts were measured by the inhibition of cis-parinaric acid (PnA) fluorescence decay in SR. Superoxide radicals were generated either by an enzymatic or a non-enzymatic system, and the scavenger ability was evaluated by the inhibition of nitrob-lue tetrazolium reduction. Methanolic extracts are more potent as scavengers of peroxyl and super oxide radicals than the ethyl ether extracts. Apparently, there is a relationship between antioxidant potency and the total phenolic groups content in each extract.     

17.

Antioxidant Activities of Some Extracts of Thymus zygis   总被引：2，自引：0，他引：2  

Jo  o R. Soare  Teresa C. P. Dinis  Ant  nio P. Cunha  Leonorm Almeida 《Free radical research》1997,26(5):469-478

The antioxidant activities of methanol and ethyl ether extracts obtained from Thymus zygis, collected during the flowering or non-flowering period, were evaluated and compared. To investigate this potential, extracts were tested on their capacity to react with diphenyl-picrylhydrazyl (DPPH) in a homogeneous medium, and to inhibit Fe²⁺/ascorbate-induced membrane lipid peroxidation, as estimated by the formation of thiobar-bituric acid-reactive substances (TBARS). Although methanol extracts reduce DPPH radicals more efficiently than ethyl ether extracts, suggesting a potent radical scavenger activity, the ethyl ether extracts were found to be most active in inhibiting lipid peroxidation in sarcoplasmic reticulum (SR) membranes. In addition, both extracts present peroxyl and superoxide radical scavenging activities. Peroxyl radicals were generated by the water soluble 2, 2A-azobis(2-amidinopropane) dihydrochloride (AAPH) azoinitiator, and the scavenging activities of the extracts were measured by the inhibition of cis-parinaric acid (PnA) fluorescence decay in SR. Superoxide radicals were generated either by an enzymatic or a non-enzymatic system, and the scavenger ability was evaluated by the inhibition of nitrob-lue tetrazolium reduction. Methanolic extracts are more potent as scavengers of peroxyl and super oxide radicals than the ethyl ether extracts. Apparently, there is a relationship between antioxidant potency and the total phenolic groups content in each extract.     

18.

菟丝子黄酮体外清除自由基活性的研究   总被引：36，自引：0，他引：36  

吴春  陈林林 《天然产物研究与开发》2005,17(5):553-556

采用DPPH体系、羟基自由基体系、烷基自由基引发的亚油酸氧化体系、超氧阴离子自由基体系对菟丝子黄酮的抗氧化活性进行研究,并同Vc、BHT进行了比较。结果表明:在试验质量浓度范围内(0.008 mg/mL~1 mg/mL),菟丝子黄酮对DPPH.、.OH自由基、O2-.自由基的清除率可达91.56%、89.39%和87.65%;其对烷基自由基的抑制率为84.22%,且其抗氧化活性强于Vc和BHT,表明菟丝子黄酮是一种天然有效的自由基清除剂。     

19.

香桃木叶片粗多酚抗氧化活性的研究   总被引：2，自引：1，他引：2  

范现丽  王高  王宏  范建芝  申晓辉 《植物研究》2009,29(3):375-379

以香桃木叶片为材料,60%乙醇提取获得粗多酚样品,并对样品的油脂抗氧化性和自由基清除能力进行研究。结果表明,未经纯化的香桃木粗多酚对油脂抗氧化效果优于BHT和V_C等人工合成抗氧化剂;在清除自由基的实验中,相同浓度的香桃木粗多酚对DPPH自由基的清除率为V_E的5倍,对羟自由基的清除效果也略优于V_C。由此可以预见香桃木粗多酚在精细加工、经纯化后抗氧化效果会更加显著。     

20.

锥序蜜心果中酚性成分的研究   总被引：1，自引：0，他引：1  

汪琼  王易芬  鞠鹏  罗士德 《天然产物研究与开发》2008,20(4)

从锥序蜜心果的乙酸乙酯部分中分离到5个化合物,通过波谱数据或与已知化合物对照,它们分别鉴定为(E)-3-(3-hydroxy-4-methoxyphenyl)acrylic acid carboxymethyl ester(1),3,4-二羟基苯甲酸(2),槲皮素-3-O-β-葡萄糖甙(3),山萘酚-3-O-α-鼠李糖甙(4)和槲皮素-3-O-α-鼠李糖甙(5),以上化合物均为首次从该属植物中分离到.     

固相萃取-高效液相色谱法测定沙苑子苷含量

目的：建立沙苑子总黄酮中沙苑子苷的含量测定方法。方法：用以氨基为固定相的固相萃取柱对沙苑子总黄酮进行纯化,洗去杂质后的洗脱液进高效液相色谱仪测定。色谱柱为VP—ODS（150mm×4．6mm,5um）,流动相为甲醇：1％HAC溶液（41：59）;流速1．2mL／min;检测波长266nm。结果：沙苑子苷在5—25μg／mL范围内呈良好的线性关系,加样回收率为102．5％,RSD2．3％。结论：本法灵敏、快速、准确,可用于测定沙苑子总黄酮中沙苑子苷的含量。     

沙棘籽提取物抗氧化活性与酚类组成的研究

采用卵磷脂脂质体体系比较了沙棘籽不同溶剂提取物的抗氧化活性,对其中的抗氧化活性成分进行了分析。试验结果表明:当浓度为250μg/mL时,提取物对共轭二烯氢过氧化物的抑制率为0~90.1%,对丙二醛的抑制率为0~88.6%。70%丙酮提取物具有最强的抗氧化活性、清除DPPH自由基能力和还原力。各提取物中主要的酚类物质为原花色素,抗氧化活性与原花色素含量有很好的相关性。     

莲子多糖的结构分析及抗氧化活性

用热水浸提、乙醇沉淀、Sevag法除蛋白分离得到水溶性莲子粗多糖。经十六烷基三甲基溴化铵（CTAB）沉淀,硼酸反应以及SephadexG-150层析纯化,得到3种莲子多糖SN1、SN2、SN3。用气相色谱、红外光谱、紫外光谱分析其化学结构。结果表明：SN1主要由葡萄糖、半乳糖组成,含a—D-吡喃葡萄糖环;SN2主链为葡聚糖、并含有其他4种单糖;SN3含7种单糖,并推测是一种酸性氨基多糖或蛋白多糖。体外抗氧化活性实验表明莲子多糖具有一定的清除自由基能力,清除·O2-的能力较强。     

不同炮制方法对玉竹提取物得率及体外抗氧化作用的影响

以多糖、总黄酮、醇溶物和水溶物的得率及体外抗氧化活性为考察指标,研究了酒蒸和蜜蒸两种炮制方法对玉竹品质的影响。结果表明：酒蒸炮制玉竹的多糖、醇溶物得率最高,蜜蒸炮制玉竹总黄酮、水溶物的得率最高,比未炮制的玉竹（生品玉竹）中相应成分的得率分别提高了43.86%、29.53%、49.46%和34.66%。将多糖、水溶性浸出物、醇溶性浸出物及总黄酮四者得率相加的和进行比较,蜜蒸最好,蜜蒸为111.069%,酒蒸为107.309%,生品玉竹为80.926%。酒蒸炮制玉竹的多糖、水溶物对DPPH自由基的清除率均高于蜜蒸玉竹和生品玉竹,其DPPH_IC50分别为0.345±0.019和0.441±0.022 mg·mL^-1;蜜蒸炮制玉竹的总黄酮、醇溶物对DPPH自由基的清除率均高于酒蒸玉竹和生品玉竹,其DPPH_IC50分别为0.047±0.011和0.199±0.036 mg·mL^-1;在浓度为1 mg·mL^-1时,蜜蒸玉竹总黄酮对DPPH自由基的清除率最大,为90.29%,超过了浓度为0.05 mg·mL^-1的芦丁和槲皮素标品对DPPH自由基的清除率。两种炮制方法均提高了多糖、水溶物、总黄酮3种提取物的还原能力,但是降低了醇溶物的还原能力。     

Antioxidant Activities of Some Extracts of Thymus zygis

The antioxidant activities of methanol and ethyl ether extracts obtained from Thymus zygis, collected during the flowering or non-flowering period, were evaluated and compared. To investigate this potential, extracts were tested on their capacity to react with diphenyl-picrylhydrazyl (DPPH) in a homogeneous medium, and to inhibit Fe²⁺/ascorbate-induced membrane lipid peroxidation, as estimated by the formation of thiobar-bituric acid-reactive substances (TBARS). Although methanol extracts reduce DPPH radicals more efficiently than ethyl ether extracts, suggesting a potent radical scavenger activity, the ethyl ether extracts were found to be most active in inhibiting lipid peroxidation in sarcoplasmic reticulum (SR) membranes. In addition, both extracts present peroxyl and superoxide radical scavenging activities. Peroxyl radicals were generated by the water soluble 2, 2A-azobis(2-amidinopropane) dihydrochloride (AAPH) azoinitiator, and the scavenging activities of the extracts were measured by the inhibition of cis-parinaric acid (PnA) fluorescence decay in SR. Superoxide radicals were generated either by an enzymatic or a non-enzymatic system, and the scavenger ability was evaluated by the inhibition of nitrob-lue tetrazolium reduction. Methanolic extracts are more potent as scavengers of peroxyl and super oxide radicals than the ethyl ether extracts. Apparently, there is a relationship between antioxidant potency and the total phenolic groups content in each extract.     

Antioxidant Activities of Some Extracts of Thymus zygis

The antioxidant activities of methanol and ethyl ether extracts obtained from Thymus zygis, collected during the flowering or non-flowering period, were evaluated and compared. To investigate this potential, extracts were tested on their capacity to react with diphenyl-picrylhydrazyl (DPPH) in a homogeneous medium, and to inhibit Fe²⁺/ascorbate-induced membrane lipid peroxidation, as estimated by the formation of thiobar-bituric acid-reactive substances (TBARS). Although methanol extracts reduce DPPH radicals more efficiently than ethyl ether extracts, suggesting a potent radical scavenger activity, the ethyl ether extracts were found to be most active in inhibiting lipid peroxidation in sarcoplasmic reticulum (SR) membranes. In addition, both extracts present peroxyl and superoxide radical scavenging activities. Peroxyl radicals were generated by the water soluble 2, 2A-azobis(2-amidinopropane) dihydrochloride (AAPH) azoinitiator, and the scavenging activities of the extracts were measured by the inhibition of cis-parinaric acid (PnA) fluorescence decay in SR. Superoxide radicals were generated either by an enzymatic or a non-enzymatic system, and the scavenger ability was evaluated by the inhibition of nitrob-lue tetrazolium reduction. Methanolic extracts are more potent as scavengers of peroxyl and super oxide radicals than the ethyl ether extracts. Apparently, there is a relationship between antioxidant potency and the total phenolic groups content in each extract.     

菟丝子黄酮体外清除自由基活性的研究

采用DPPH体系、羟基自由基体系、烷基自由基引发的亚油酸氧化体系、超氧阴离子自由基体系对菟丝子黄酮的抗氧化活性进行研究,并同Vc、BHT进行了比较。结果表明:在试验质量浓度范围内(0.008 mg/mL~1 mg/mL),菟丝子黄酮对DPPH.、.OH自由基、O2-.自由基的清除率可达91.56%、89.39%和87.65%;其对烷基自由基的抑制率为84.22%,且其抗氧化活性强于Vc和BHT,表明菟丝子黄酮是一种天然有效的自由基清除剂。     

香桃木叶片粗多酚抗氧化活性的研究

以香桃木叶片为材料,60%乙醇提取获得粗多酚样品,并对样品的油脂抗氧化性和自由基清除能力进行研究。结果表明,未经纯化的香桃木粗多酚对油脂抗氧化效果优于BHT和V_C等人工合成抗氧化剂;在清除自由基的实验中,相同浓度的香桃木粗多酚对DPPH自由基的清除率为V_E的5倍,对羟自由基的清除效果也略优于V_C。由此可以预见香桃木粗多酚在精细加工、经纯化后抗氧化效果会更加显著。     

锥序蜜心果中酚性成分的研究

从锥序蜜心果的乙酸乙酯部分中分离到5个化合物,通过波谱数据或与已知化合物对照,它们分别鉴定为(E)-3-(3-hydroxy-4-methoxyphenyl)acrylic acid carboxymethyl ester(1),3,4-二羟基苯甲酸(2),槲皮素-3-O-β-葡萄糖甙(3),山萘酚-3-O-α-鼠李糖甙(4)和槲皮素-3-O-α-鼠李糖甙(5),以上化合物均为首次从该属植物中分离到.