油橄榄中橄榄苦苷的提取及纯化工艺研究

采用ODS C18色谱柱,流动相为甲醇:水(0.2%醋酸)体积比45:55,检测波长为230 nm,建立油橄榄叶中橄榄苦苷的HPLC分析方法。采用单因素和正交试验筛选优化油橄榄叶橄榄苦苷浸提的最佳工艺,并进一步研究大孔树脂静态和动态吸附和解吸附性能。结果表明:1)热回流浸提的最佳工艺为乙醇体积分数80%,温度70℃,提取时间3.5 h,料液比1:15(g:mL),提取次数2次。2)通过对比不同树脂对橄榄苦苷的吸附,筛选出选择性吸附好的AB-8树脂,吸附量为每克湿树脂32.1 mg。AB-8树脂纯化的最佳条件为:上样质量浓度为2 g/L,70%乙醇-水洗脱,流速为3 mL/min,洗脱液用量为3 BV。3)橄榄苦苷的粗提物经过AB-8树脂纯化后,橄榄苦苷的纯度达到47.90%,黄酮含量为16.4%,收率为6.43%。     

木樨榄属植物中裂环烯醚萜类的提取方法及开发前景

裂环烯醚萜类化合物是木樨榄属植物标记性化合物,尤其是橄榄苦苷具有重要的药理活性。本文作者研究了作者裂环烯醚萜类化合物植物来源、化学结构特征和物化性质及药理作用,提出木樨榄属油橄榄叶提取物加工工艺和橄榄苦苷的检测方法,为我国油橄榄叶中橄榄苦苷的加工利用提供依据。     

黑果腺肋花楸有效物质的提取及抗氧化和降糖活性研究

以黑果腺肋花楸多酚含量、黄酮含量及出膏率为考察指标,采用单因素实验和正交实验并通过多指标综合评分法优化黑果腺肋花楸多酚和黄酮的提取工艺;通过对DPPH的清除能力评价其抗氧化活性;并通过建立肝细胞高糖损伤模型,比较提取物组与模型组葡萄糖消耗量评价其降糖活性.结果表明,黑果腺肋花楸多酚和黄酮的最佳提取工艺为:超声功率120...     

中国油橄榄发展历程与产业展望

介绍了我国油橄榄的引种和推广历程,分析了我国油橄榄引种试验、示范推广和产业开发3个阶段,进一步介绍了甘肃陇南油橄榄的发展历程。重点介绍了橄榄油、橄榄果渣和橄榄叶的化学成分及其加工利用现状。在此基础上,结合我国目前油橄榄的现状和需求,提出油橄榄果叶综合利用的发展思路,开发高品质橄榄油、系列化妆品、洗涤用品、油橄榄茶、油橄榄酒、餐用橄榄、橄榄叶抗氧化剂及果渣保水调节剂,全值化利用油橄榄,提高油橄榄利用率,促进我国油橄榄产业的发展。     

油橄榄叶的化学成分及其在化妆品领域的研究进展

油橄榄叶占油橄榄收获总量的10%,是一种低廉且丰富的可再生资源,其提取物中含有橄榄苦苷、木犀草苷、羟基酪醇等丰富的酚类衍生物,具有抗氧化、光保护、消炎抗菌、美白等活性,近年来较多应用在化妆品领域,本文对油橄榄叶的化学成分及其在化妆品方面的活性、作用机制及目前的应用进展进行了综述,以期为化妆品开发提供研究基础。     

橄榄苦苷对皮肤的生物活性研究进展

橄榄苦苷是油橄榄叶提取物中主要的多酚成分之一，具有优异的抗炎、抗氧化活性以及其他治疗功效。本文从抑制细胞中NF-κB的核易位，抑制一氧化氮合成酶（iNOS）、环氧合酶-2(COX-2)的表达，减少促炎细胞因子和趋化因子等方面总结了橄榄苦苷抗炎的作用通路，并进一步综述了其抗氧化、抗菌、美白以及抗衰的作用机理，旨在为橄榄苦苷在化妆品中的开发和应用提供理论参考。     

对不同方法提取苦丁茶多酚的比较试验

本文通过使用不同的提取溶剂，不同的提取时间，对从苦丁茶中提取茶多酚进行了研究。另外，本文对大叶苦丁茶和小叶苦丁茶中所含茶多酚进行了比较。在溶剂浸提中，从成品小叶苦丁茶中提取多酚，提取质量以70%乙醇作溶剂最多，其次为95%、50%、40%，从水中提取最少；多酚含量同样是70%乙醇作溶剂最高，以水作溶剂最低。在成品大叶苦丁茶中，提取质量随浓度的增高而增多，而多酚含量也同样呈递增的趋势。在新鲜大叶苦丁茶中，提取质量以95%为最高，其次为60%、80%、50%，水中提取最少；而多酚含量则呈递增趋势。采用相同的溶剂提取与分析方法，苦丁茶提取物的质量：成品小叶>成品大叶>新鲜大叶；多酚含量则：成品大叶>新鲜大叶>成品小叶。     

珙桐叶甲醇提取物的分离纯化

以珙桐叶甲醇提取物为研究对象,比较12种吸附树脂:HZ-801、HZ-803、HZ-816、DM-4、XDA-5、306、D101、AB-8、CAD-40、D-5、YPR-I和聚酰胺对提取物中多酚和黄酮类化合物的吸附及解吸性能。结果表明:聚酰胺对珙桐叶提取物的分离纯化效果最好,聚酰胺对珙桐叶甲醇提取物中多酚的吸附率和解吸率分别达到了54.85%和46.13%而对黄酮的吸附率和解吸率则分别达到了48.92%和52.65%。     

红外差谱及光谱拟合对雷竹叶提取黄酮的品质鉴定

用福建雷竹叶提取竹叶总黄酮,以槲皮素和芦丁为标准品,KB r压片法在FT-IR上测定标准品及提取物的红外图谱,确定提取物为竹叶总黄酮。对标准品与提取物进行差谱和拟合处理,结果表明以芦丁要较槲皮素作标准品更为可靠。此红外技术可作为鉴定黄酮品质及纯度的定性方法。     

油楠叶中黄酮提取及抗氧化活性研究

通过研究油楠叶不同溶剂提取物的抗氧化性能,为丰富和提高油楠树的药用价值及生物活性打下基础,开发天然抗氧化剂提供依据。本实验采用紫外-可见分光光度法,研究油楠叶不同溶剂提取物中总黄酮含量。经分析油楠叶不同溶剂提取液的总黄酮含量和与其自由基清除能力之间的关系发现:油楠叶不同溶剂提取物的抗氧化能力与总黄酮呈现正相关的关系,即总黄酮含量越高,其清除自由基能力越强。     

Isolation of polyphenols from the extracts of olive leaves (Olea europaea L.) by adsorption on silk fibroin

General objective of the present work was to assess the isolation of polyphenols from olive leaves. The effects of extraction conditions on the total phenol content and antioxidant activity of olive leaf extract (OLE) were investigated. An extract with good antioxidant activity (7.52 mmol of Trolox equivalent antioxidant capacity (TEAC)/g olive leaf extract), and a high content of oleuropein (13.4%) and rutin (0.18%) could be obtained using 70% ethanol as extraction solvent. There was a good correlation between the antioxidant activity and the total phenol content. Furthermore, silk fibroin was used as a novel adsorbent to recover the polyphenols from the olive leaf extracts. The adsorbed amounts of rutin and oleuropein were 15 mg rutin/g silk fibroin and 96 mg oleuropein/g silk fibroin. Fraction consisting of mainly oleuropein and fraction rich in rutin, luteolin-7-glucoside, verbascoside, apigenin-7-glucoside were obtained by using silk fibroin filled column. Silk fibroin was found to be a promising adsorbent for the purification of oleuropein and rutin from olive leaf extracts.     

草果不同极性萃取物总黄酮、总多酚含量与其抗氧化活性的相关性

以草果为原料,通过50%乙醇、水、乙酸乙酯、丙酮、正丁醇、甲醇和石油醚不同极性溶剂萃取活性物质,探讨萃取物中总黄酮和总多酚含量与总还原能力及对DPPH自由基清除率、ABTS⁺自由基清除率、OH^-自由基清除率、NO^-₂清除能力的相关性。结果表明:50%乙醇萃取物总黄酮和总多酚含量均最高,各萃取物均有抗氧化能力,且呈明显的量效关系,其中50%乙醇萃取物总还原能力、清除ABTS⁺和DPPH能力最强,石油醚萃取物清除OH^-和NO^-₂能力最强。相关性分析表明,草果萃取物中总黄酮含量与ABTS⁺清除能力呈极显著相关,与DPPH清除能力呈显著相关,总多酚含量与ABTS⁺和DPPH的清除能力呈极显著相关,可为草果作为天然抗氧化剂提供理论依据。     

苦水玫瑰花生物活性成分的分析

利用热风干燥和冷冻干燥方法对鲜苦水玫瑰花进行了干燥处理,然后测定了不同干花粉与鲜花中的多糖、还原糖、黄酮、多酚、核酸等5种活性成分的含量及其抗氧化活性。结果发现,这批苦水玫瑰的平均含水率约为83%,多糖质量分数约为1.95%,还原糖质量分数约为4.51%,黄酮质量分数约为4.41%,多酚质量比约为91 mg/g,核酸质量比约为5.45 mg/100 g。玫瑰花的水提物具有清除DPPH自由基的能力。此外还发现经冷冻干燥处理的玫瑰花对活性成分的保存能力要优于热风干燥处理。     

Comparative study of modeling the stability improvement of sunflower oil with olive leaf extract

Commercially available sunflower oil was enriched in polyphenols by adding olive leaf extract. After extracting the dried and ground olive leaves with the assistance of homogenizer, total phenolic content (TPC) and oleuropein concentration of the extract were determined. The dried extract was partially dissolved into the sunflower oil to increase the quality and shelf-life of the oil enriched by the substances in the plants by means of solid-liquid extraction method. A face central composite design (FCCD) through response surface methodology (RSM) was used to investigate the effects of enrichment conditions (extract content, time and mixing speed) on the responses, TPC and oleuropein concentration of the enriched sunflower oil as well as to design of experiments, to model and to optimize the process. The enriched sunflower oil obtained at optimum conditions was evaluated in terms of its TPC, oleuropein, total carotenoid content (TCC), antioxidant activity (AA), peroxide value (PV) and induction time (IT), depending on those of the crude oil. Furthermore, artificial neural networks (ANN) were also employed to compare the predicted results of RSM.     

Impact of Aromatization by Citrus limetta and Citrus sinensis Peels on Olive Oil Quality,Chemical Composition and Heat Stability

The objectives of this work were to study the impact of aromatization by sweet lemon and sweet orange peels on olive oil quality, chemical composition and heat stability. Flavored olive oils were prepared by maceration of sweet lime and sweet orange zests at 1, 3 and 5 %. The oil samples were kept at 60 °C for 40 days. Physicochemical tests (FFA, PV, oxidative stability, polyphenols and pigments contents) were carried out. The antioxidant activity (β‐carotene‐linoleate bleaching assay, DPPH radical scavenging and reducing power) was also tested. Results indicated that the addition of citrus zests contributed to the increase in polyphenols and carotenoids contents. Moreover, it led to an increase in the DPPH‐radical scavenging activity (99.50 % for flavored olive oil with sweet orange zests at 5 %). Flavored olive oils with sweet orange zests were more stable to heat treatment than those flavored with sweet lemon zests. The degradation rate of bioactive compounds was lower for virgin olive oil comparing to flavored oils.     

Phytochemical Screening and Polyphenolic Antioxidant Activity of Aqueous Crude Leaf Extract of Helichrysum pedunculatum

We evaluated the in vitro antioxidant property and phytochemical constituents of the aqueous crude leaf extract of Helichrysum pedunculatum. The scavenging activity on superoxide anions, DPPH, H₂O₂, NO and ABTS; and the reducing power were determined, as well as the flavonoid, proanthocyanidin and phenolic contents of the extract. The extract exhibited scavenging activity towards all radicals tested due to the presence of relatively high total phenol and flavonoids contents. Our findings suggest that H. pedunculatum is endowed with antioxidant phytochemicals and could serve as a base for future drugs.     

GxE Effects on Tocopherol Composition of Oils from Very Old and Genetically Diverse Olive Trees

Tocopherols are compounds with high biological activity, beneficial for human health that can be found in vegetable oils like olive oil, contributing for its resistance to oxidation. In this work, the tocopherol contents of olive oils extracted from centenarian olive trees of six cultivars (cvs. Lentisca, Madural, Rebolã, Redondal, Verdeal, and Verdeal Transmontana) were evaluated during five consecutive crop seasons (2013–2017). Three tocopherol isoforms (α-, β- and γ-tocopherols) were detected in all analyzed olive oils, and their content varied significantly with the cultivar and year of production. The highest amounts were found in cv. Lentisca (456 ± 122 mg/kg olive oil), while the lowest were observed in cv. Verdeal (179 ± 45 mg/kg olive oil). Crop year was the most influential factor, with the highest contents observed in 2013 and lowest in 2014. Principal component analysis and hierarchical clustering analysis helped differentiate olive oils according to cultivar or production year. These data suggest that tocopherol composition may serve as a chemical marker to distinguish the subject cultivar olive oils from centenarian trees either by olive cultivar or by crop year, being some cultivars identified as potential candidates for guaranteeing the production of olive oils rich in these compounds.     

Stability of refined olive oil and olive‐pomace oil added by phenolic compounds from olive leaves

Refined olive oil and olive‐pomace oil were enriched with olive leaf phenolic compounds in order to enhance its quality and bring it closer to virgin olive oil. The changes that occurred in the concentrations of pure oleuropein, oleuropein aglycone, hydroxytyrosol acetyl and α‐tocopherol at 400 µg/kg of oil during the storage of refined olive oil and olive‐pomace oil under accelerated conditions (50 °C) were investigated. In a period of 4 months, α‐tocopherol decomposed by 75% whereas less than 40% of the phenols were lost. During storage, enzymatic olive leaf extract hydrolysate that contains two major compounds, hydroxytyrosol and oleuropein aglycone showed the highest antioxidant activity and the lowest detected stability, followed by oleuropein. The oleuropein in olive leaf extracts exhibited similar degradation profiles, reducing by 60–50% and 80% for the olive oil and olive‐pomace oil in 6 months, respectively. The acetylated extract, however, displayed a loss of 10 and 5% in olive oil and olive‐pomace oil, respectively. In the fatty acid composition, an increase in oleic acid and a decrease in linoleic acid were observed. The antiradical activities of the olive oil and olive‐pomace oil enriched with olive leaf phenolic compounds at 400 ppm showed that enzymatic hydrolysate extract had the highest protective effect against oil oxidation. Based on the Rancimat method, the oils with added leaf enzymatic hydrolysate extract had the lowest peroxide value and the highest stability. After 6 months of storage and at 120 °C, the oxidative resistance of refined olive oil and olive‐pomace oil reached 0.71 and 0.89 h, respectively, whereas that of the non‐enriched samples fell to zero.     

从竹叶中同步提取多糖、茶多酚和黄酮的研究

研究高压脉冲电场法同步提取竹叶中黄酮、茶多酚和多糖的工艺。以竹叶为原料,在电场强度、脉冲数、提取介质pH和料液比4个单因素实验的基础上,采用L9(34)正交实验确定最优化工艺。结果表明,采用高压脉冲电场法进行同步提取,竹叶黄酮、茶多酚和多糖提取率分别可达到2.48%,0.93%和3.54%,竹叶黄酮与多糖的提取率比传统方法提高了25%以上,但茶多酚的提取率略有降低。该工艺可同步有效地从竹叶中提取黄酮、茶多酚和多糖,对于综合开发竹叶活性成分具有指导意义。     

Solid/liquid extraction and isolation by molecular distillation of hydroxytyrosol from Olea europaea L. leaves

Molecular distillation, or short‐path distillation (SPD), is particularly appropriate for processing of low‐volatility compounds, which are easily altered at high temperature. Olea europaea L. leaves constitute an olive tree by‐product very interesting for their natural antioxidants content. In this research, molecular distillation technology has been applied to obtain high‐value‐added compounds by the SPD fractionation of an olive tree leaf extract. The process consists of two stages: (a) ethanolic extraction of the olive leaves, followed by incorporation of the extract into glycerine and (b) molecular distillation of the glycerine enriched in olive leaf extract compounds (terpenic and phenolic compounds). Four molecular distillation tests under different conditions were carried out. Results showed that 80.9% 3,4‐dihydroxy‐phenylethanol (hydroxytyrosol) was recovered from the glycerine admixture under a pressure of 1.50–2.00 mbar, a temperature of 190 °C and a feed rate of 15 mL/min.