巨尾桉单宁的提取分离及其抗菌抗氧化性能

采用超声波辅助法提取了巨尾桉叶中的单宁,大孔树脂吸附法纯化了粗提物,考察了提取物对8种常见菌种的抑制作用和对H2O2、DPPH.和.OH的清除作用。结果表明,巨尾桉单宁的提取得率为4.01%;经树脂分离纯化后单宁质量分数达到53.12%;巨尾桉单宁对除大肠杆菌外的供试菌种均有较强的抑制作用,纯化后的单宁对金黄色葡萄球菌、酵母菌和痢疾杆菌的最低抑菌质量浓度(MIC)均为1.0 g/L,对蜡状芽孢杆菌和沙门氏菌的抑制作用优于阳性对照物;粗提物、纯化物在质量浓度为0.50 g/L时对H2O2有最大清除率,分别为80.00%、89.12%,其IC50分别为0.11、0.12 g/L;抗坏血酸、粗提物和纯化物均在质量浓度为1.50 g/L时对DPPH.有最大清除率,分别为98.43%、88.97%和92.21%。在清除.OH体系中,粗提物、纯化物均在质量浓度为4.00 g/L时有最大清除率,分别为87.52%和94.32%,各试样对.OH的清除能力依次为抗坏血酸>纯化物>粗提物。     

槐米黄酮的纯化和体外抗氧化活性研究

研究了槐米黄酮的纯化条件和体外抗氧化活性。结果表明,槐米黄酮经聚酰胺柱层析的最适纯化条件:黄酮上样液pH值6～7,质量浓度5 mg/mL,上样量1.5 BV,吸附流速1.0 mL/min,用3 BV去离子水清洗聚酰胺柱,4 BV解吸液80%乙醇溶液,解吸流速1.5 mL/min,聚酰胺树脂反复使用5次后进行再生处理。以Vc为阳性对照,槐米黄酮具有一定的体外抗氧化能力,其中在高浓度区间对·DPPH有较好的清除效果,且与Vc接近,对·O^-_2和·OH都有一定的自由基清除能力,但效果稍差于Vc,对Fe-_2和·OH都有一定的自由基清除能力,但效果稍差于Vc,对Fe⁽³⁺⁾有较好还原力,且在较低和较高质量浓度范围内好于Vc。     

蒙山莴苣总黄酮的纯化及体外抗氧化活性研究

研究了蒙山莴苣总黄酮的纯化条件和体外抗氧化能力。结果表明,最佳的聚酰胺柱层析纯化条件为:用p H 5～6,质量浓度5. 21 mg/m L的上样液1. 5 BV,按1. 5 m L/min上样,用4 BV水淋洗,4. 5 BV 80%乙醇溶液(V/V)按1. 5 m L/min解吸,聚酰胺每使用5次可以进行一次再生。以VC为对照,蒙山莴苣总黄酮对DPPH自由基、·O-2和·OH都有一定的清除能力,对Fe3+有一定的还原能力,但效果均弱于VC。     

蒙山莴苣总黄酮的纯化及体外抗氧化活性研究

研究了蒙山莴苣总黄酮的纯化条件和体外抗氧化能力。结果表明,最佳的聚酰胺柱层析纯化条件为:用p H 5～6,质量浓度5. 21 mg/m L的上样液1. 5 BV,按1. 5 m L/min上样,用4 BV水淋洗,4. 5 BV 80%乙醇溶液(V/V)按1. 5 m L/min解吸,聚酰胺每使用5次可以进行一次再生。以VC为对照,蒙山莴苣总黄酮对DPPH自由基、·O-2和·OH都有一定的清除能力,对Fe3+有一定的还原能力,但效果均弱于VC。     

藁本黄酮的纯化及体外抗氧化活性研究

研究了藁本黄酮纯化的工艺条件及纯化前后藁本黄酮的体外抗氧化活性。结果表明,以D-101大孔树脂纯化藁本黄酮的最佳条件为:体积2.5 BV、浓度2.5 mg/mL、pH 4的上样液以3 mL/min流速上样后,用体积5 BV、浓度70%的乙醇溶液以2 mL/min流速洗脱,此条件下藁本黄酮回收率可达81.88%,样品纯度达到71.09%。纯化后藁本黄酮的抗氧化性明显高于纯化前,其清除DPPH自由基、超氧阴离子自由基和羟基自由基的IC_(50)值分别为386.8,764.0,953.3μg/mL。     

大孔吸附树脂纯化杏仁皮单宁工艺的研究

通过静态吸附及解吸实验,考察5种大孔吸附树脂对杏仁皮单宁的吸附及解吸性能,确定效果最佳的大孔吸附树脂。考察上样浓度、上样流速、上样量对吸附性能的影响,乙醇浓度、洗脱流速、洗脱液用量对解吸性能的影响。结果表明,最佳纯化条件为:采用HP-20型大孔吸附树脂,上样液浓度为1.20 mg/mL,上样流速为1 BV/h,上样量为4 BV,洗脱液为70%乙醇溶液,洗脱液用量为3 BV,洗脱流速为1.5 BV/h。在此条件下,杏仁皮单宁纯度由9.97%提高到32.58%。表明HP-20型大孔吸附树脂纯化杏仁皮单宁工艺可靠、效果良好。     

大孔吸附树脂纯化杏仁皮单宁工艺的研究

通过静态吸附及解吸实验,考察5种大孔吸附树脂对杏仁皮单宁的吸附及解吸性能,确定效果最佳的大孔吸附树脂。考察上样浓度、上样流速、上样量对吸附性能的影响,乙醇浓度、洗脱流速、洗脱液用量对解吸性能的影响。结果表明,最佳纯化条件为:采用HP-20型大孔吸附树脂,上样液浓度为1.20 mg/mL,上样流速为1 BV/h,上样量为4 BV,洗脱液为70%乙醇溶液,洗脱液用量为3 BV,洗脱流速为1.5 BV/h。在此条件下,杏仁皮单宁纯度由9.97%提高到32.58%。表明HP-20型大孔吸附树脂纯化杏仁皮单宁工艺可靠、效果良好。     

香蕉皮多酚提取及其抗氧化性研究

采用内部沸腾法技术提取香蕉皮多酚,考察解吸剂浓度、解吸剂用量、解吸时间、提取温度、提取时间、提取剂体积及提取剂七个因素对香蕉皮多酚物质提取工艺的影响,确定香蕉皮多酚类物质适宜的提取工艺参数;通过体外实验分析香蕉皮多酚提取物不同萃取部分对DPPH自由基的清除能力。结果表明最优工艺为:解吸剂浓度为60%乙醇、解吸剂用量为5 mL/g、解吸时间为20 min,提取剂选取温度为100℃的蒸馏水、提取剂用量为20 mL/g、提取时间为4 min。在该条件下多酚提取得率为4.628%,所提取的香蕉皮多酚具有较强的清除DPPH自由基能力,其中正丁醇萃取部分清除DPPH自由基的能力最强。     

大孔吸附树脂分离纯化猪毛菜总黄酮及其抗氧化活性

采用不同大孔吸附树脂分离纯化猪毛菜总黄酮,并对纯化后的总黄酮进行体外抗氧化活性测试。通过考察影响树脂静态和动态吸附与洗脱的主要因素,确定猪毛菜总黄酮分离纯化优化工艺条件。静态吸附实验表明,AB-8树脂分离纯化效果较好,并且吸附符合Langmuir和Freundlich方程。动态吸附和解吸的最佳工艺条件为:上样液质量浓度1.25 g/L、p H=4.5、上样流速2 m L/min、上样量2.5 BV(BV指树脂柱内装载树脂的体积)、洗脱剂为体积分数80%的乙醇溶液、洗脱流速1.0 m L/min,洗脱剂用量4 BV。所得洗脱液中黄酮质量分数从纯化前10.20%增加到纯化后51.89%,回收率为84.43%。体外实验表明,纯化后的黄酮可以清除羟自由基和超氧阴离子自由基,并有较好的还原力。纯化后的黄酮可以作为一种潜在的天然抗氧化剂。     

丹参-葛根药对提取物的纯化工艺及抗氧化活性研究

为了将丹参-葛根药对粗提物进一步加工成抗氧化保健品,研究该粗提物的大孔树脂纯化工艺。以丹酚酸B、葛根素含量为指标,通过对九种大孔树脂的静态吸附量和解吸率的考察,筛选出合适的树脂,优化纯化工艺。同时采用DPPH自由基法测定粗提物、纯化物的抗氧化活性。结果表明:D101型大孔树脂的纯化工艺为:上样浓度30 mg·mL~(-1),上样量2 BV,除杂剂水用量为3 BV,洗脱剂乙醇浓度为50%,用量为3.5 BV。经树脂纯化后,丹酚酸B和葛根素的含量分别提高了3.33倍、4.03倍,多糖含量明显降低,丹参-葛根提取物清除DPPH自由基的IC_(50)由0.048 3 mg·mL~(-1)降至0.010 4 mg·mL~(-1),抗氧化能力显著增强。该纯化工艺有效地提高了丹酚酸B和葛根素的含量,利于抗氧化保健品的研发。     

紫背天葵黄酮的体内外抗氧化作用

采用体积分数80%的乙醇提取紫背天葵中的总黄酮并测定其含量,将粗提液萃取,经AB-8型大孔吸附树脂纯化,以Vc为对照,测定紫背天葵总黄酮粗提液、纯化液对二苯代苦味酰基自由基(DPPH.)、羟基自由基(.OH)和超氧阴离子自由基(O2-.)的清除能力,并考察紫背天葵黄酮纯化物的体内抗氧化效果。结果表明,紫背天葵中粗黄酮含量为13.928 mg/g,纯化比率为32.79%;紫背天葵总黄酮粗提液、纯化液对3种自由基均有不同程度的清除作用,且清除作用随黄酮质量浓度的升高而增强,纯化液的清除作用强于粗提液;低剂量紫背天葵黄酮纯化物实验组小鼠肝脏和脑组织中超氧化物歧化酶(SOD)活力和肝脏过氧化氢酶(CAT)活力显著高于对照组(p<0.05),而脑中的丙二醛(MDA)含量显著低于正常对照组(p<0.05)。     

黑荆树皮单宁不同级分的抑菌性能

通过对黑荆树皮单宁进行醇沉纯化 ,可以使单宁质量分数提高 1 0 %。在此基础上进行萃取分级 ,可得到相对分子质量分布范围不同的单宁级分。各级分的抑菌性能与其浓度和pH有关。根据最低抑菌浓度 (MIC)测试结果 ,黑荆树皮单宁各级分在适宜pH条件下的抑菌性能依次为 :乙酸乙酯级分 >乙醚级分 >纯化后单宁 >水级分 >未纯化单宁。各级分在 1 0g dL质量浓度下对所选霉菌和酵母菌无抑制作用。     

Characterization and antioxidative properties of condensed tannins from the mangrove plant Aegiceras corniculatum

Freeze‐dried leaf, stem bark, and root bark powders of Aegiceras corniculatum were extracted with three different types of polar solvents: methanol, ethyl acetate, and water. The methanol extracts had the highest concentrations in total phenolics and extractable condensed tannins, followed by water and ethyl acetate extracts. Analysis by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) suggested that condensed tannins from leaf, stem bark, and root bark contained prodelphinidins and procyanidins, with the predominance of prodelphinidins and high level of galloylation. Acid‐catalyzed degradation in the presence of benzyl mercaptan indicated that gallocatechin, epigallocatechin, epigallocatechin‐3‐O‐gallate, and epicatechin‐3‐O‐gallate occurred as the terminal units and (epi)gallocatechin, (epi)gallocatechin‐3‐O‐gallate, (epi)catechin, and (epi)catechin‐3‐O‐gallate occurred as the extension units. The mean degrees of polymerization (mDP) of condensed tannins from leaf, stem bark, and root bark were 13.5, 7.4, and 12.3, respectively. The condensed tannins from leaf and stem bark exhibited a higher DPPH radical scavenging activity and ferric reducing/antioxidant power compared to that of synthetic antioxidant butylated hydroxyanisole (BHA). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

藤茶多酚分离纯化及其对口腔变形链球菌抑制作用研究

采用Folin-Ciocaileu比色法测定藤茶多酚质量浓度,计算吸附率和洗脱率,比较5种不同性质大孔树脂对藤茶多酚静态吸附和解吸的影响,优选出HPD-100型树脂。进一步通过单因素试验得到藤茶多酚分离纯化的优选工艺条件为:上样液藤茶多酚粗提物质量浓度2.4 g/L、流速2.0 BV/h、体积6.5 BV;洗脱剂乙醇体积分数60%、流速3 BV/h、体积7.5 BV。在此条件下,经大孔树脂处理后藤茶多酚质量分数由29.9%提高到69.8%。抑菌试验表明,经大孔树脂处理后的藤茶提取物具有显著抑制口腔变形链球菌生长的作用,其最低抑菌浓度为3.13 g/L。     

Comparison of Chemical Compositions and Antioxidant Activities of Condensed Tannins From Different Parts of Calliandra haematocephala

In this study, the condensed tannins in 70% acetone extracts of leaf, twig, and stem bark of Calliandra haematocephala were purified by a Sephadex LH-20 column, and their structures were identified using MALDI-TOF-MS and thiolysis-HPLC-ESI-MS analyses. The results showed that the condensed tannin structures varied significantly among C. haematocephala organs. The condensed tannins from leaf were essentially of prodelphinidins, consisting mainly of (epi)gallocatechin and (epi)gallocatechin-3-O-gallate units; the condensed tannins from twig and stem bark were predominately of procyanidins, with catechin, epicatechin, and (epi)catechin-3-O-gallate as the main constitutive units for the former and epicatechin as the main constitutive unit for the latter, respectively. Furthermore, in vitro antioxidant activities of these condensed tannins were evaluated using the ABTS^·+ and FRAP methods. All of the condensed tannins exhibited stronger antioxidant activities compared to those of synthetic antioxidant BHA. For all organs, the two tested activities were found to be the highest in leaf condensed tannins, followed by that in twig condensed tannins and stem-bark condensed tannins. The results suggested that the number of hydroxyl groups on the B-ring and the level of 3-O-galloylation in condensed tannins were closely related with their antioxidant activities, and that the condensed tannins from different parts of C. haematocephala could be used as a natural additive in the food and cosmetic industries.     

木醋液体外抗氧化活性评价

对比了白桦、杂木、木屑以及蒸馏木屑4种木醋液的还原能力,二苯基苦基肼自由基(DPPH·)的清除能力和羟基自由基(·OH)的清除能力。结果表明,4种木醋液有较强的还原能力,其中还原能力最强的是木屑木醋液,半数有效浓度(EC₅₀)为(1.73±0.06)g/L;4种木醋液可有效清除DPPH·,木屑木醋液清除效果最佳,半数抑制浓度(IC₅₀)为(0.20±0.01)g/L;4种木醋液的·OH清除能力相对较弱,除木屑木醋液IC₅₀为(9.69±0.20)g/L外,其他3种木醋液清除率均未达到50%。     

川佛手中多酚提取工艺优化及抗氧化研究

采用超声波法提取川佛手中的多酚。通过单因素试验研究了提取温度、乙醇体积分数、料液比和提取时间等因素对提取效率的影响。在此基础上,进行L9(34)正交试验,确定了多酚的最佳提取工艺参数:提取温度为50℃,乙醇体积分数为60%,料液比为1∶30 g·mL-1,提取时间为1.5 h,最大提取率达到1.95%。以抗坏血酸(VC)为对照,测定川佛手多酚提取物的DPPH·和·OH的清除率,结果表明川佛手多酚具有较强的抗氧化活性。     

Separation,Identification, Antioxidant,and Anti-Tumor Activities of Hibiscus sabdariffa L. Extracts

Roselle (Hibiscus sabdariffa L.) belongs to the malvaceae family. Its calyx is used for making jellies, jams, and beverages. Despite it usefulness, there are few or no studies on the purification and structural identification of HAs and Roselle extracts. This paper therefore seeks to investigate the purification and structural identification of Hibiscus sabdariffa L. extracts, and to evaluate their antioxidant activities on DPPH and ABTS and anti-tumor activities on human cervical cancer HeLa cells of purified fractions. Two fractions (fraction 1 and fraction 2) from Roselle (Hibiscus sabdariffa L.) extracts were purified with C-18 Sep-Pak cartridge, followed by Sephadex LH-20 column and characterized by HPLC-ESI-MS/MS. The contents of the anthocyanins in fraction 1 and fraction 2 were 863.41 mg/g and 617.35 mg/g, respectively. Nine compounds were identified with HPLC-ESI-MS/MS, seven of which have not been reported before in Roselle. Two fractions and HAs-rich extracts purified with C-18 Sep-Pak cartridge showed high capacity on radicals scavenging and HeLa cells inhibition in a dose-dependent manner. The orders of both activities were: fraction 1 > fraction 2 > HAs-rich extracts. IC₅₀ values of fraction 1 on DPPH and ABTS radicals were 17.14 ± 2.24 μg/mL and 85.91 ± 6.72 μg/mL, respectively. The cell inhibition ratio of fraction 1 against HeLa cells reached 83.67 ± 3.07% at the concentration of 200 μg/mL. Two fractions and HAs-rich extracts could be a good supplements for natural antioxidant and anti-tumor activities.