Antioxidant oligomeric proanthocyanidins from sea buckthorn (Hippophae rhamnoides) Pomace

After flavonol glycosides, monomeric flavan-3-ols, and dimeric and trimeric proanthocyanidins were fractionated from an extract of sea buckthorn (Hippophae rhamnoides) pomace by Sephadex LH-20 gel chromatography, oligomeric proanthocyanidins were eluted. The oligomeric fraction accounted for 84% of the total proanthocyanidins and 75% of the total antioxidant activity of the sea buckthorn pomace extract. To elucidate the structure of the oligomeric fraction, it was depolymerized by acid catalysis in the presence of phloroglucinol. The structure of the resulting flavan-3-ol monomers and flavan-3-ol-phloroglucinol adducts was determined by electrospray ionization mass spectrometry (ESI-MS) and (1)H and (13)C nuclear magnetic resonance (NMR) spectroscopy. Quantitative high-performance liquid chromatography investigations demonstrated (+)-gallocatechin as the predominating subunit in the oligomeric fraction. This observation was confirmed by ESI-MS, matrix-assisted laser desorption/ionization mass spectrometry, and (13)C NMR spectroscopy. The results showed that the majority of the flavan-3-ol subunits possessed a 2,3-trans configuration. The oligomers consisted mainly of prodelphinidin subunits whereas procyanidins were present in smaller amounts, indicating a very uncommon composition of the sea buckthorn proanthocyanidins. The mean degree of polymerization of the oligomeric proanthocyanidins was between 6 and 9.     

Rheology of sea buckthorn (Hippophae rhamnoides L.) juice.

Juice extracted from sea buckthorn fruits was subjected to dynamic rheological measurements in a controlled stress rheometer. Sea buckthorn juice exhibited wide variations in flow behavior from pseudoplastic to dilitant with increasing temperature. The power law model suitably (r >/= 0.975, P相似文献   

Tocopherols and tocotrienols in sea buckthorn (Hippophae rhamnoides L.) berries during ripening

Sea buckthorn berries ( Hippophae rhamnoides L.) are used in foods, cosmetics, and pharmaceutical products. They are of particular interest for their high content of healthy phytochemicals, including vitamin E-related compounds (tocopherols and tocotrienols). This study investigated the content of tocopherols and tocotrienols during ripening in berries from four cultivars of sea buckthorn over a three-year period. The results showed large variations in tocopherols and tocotrienols depending on harvest date, cultivar, and year. Levels of alpha-tocopherol were higher early in the ripening period, while at later dates, delta-tocopherol levels increased. Great differences in amounts and composition of tocopherols and tocotrienols were observed between cultivars. Tocopherol levels were positively correlated with daily temperature, but this trend varied between years. Variations in tocopherols and tocotrienol levels in sea buckthorn berries due to cultivar, year, and ripening stage should therefore be considered in the production of nutritional products.     

Changes in antioxidant effects and their relationship to phytonutrients in fruits of sea buckthorn (Hippophae rhamnoides L.) during maturation

Different fractions of sea buckthorn fruits were investigated for antioxidant activity and its relationship to different phytonutrients. Capacity to scavenge radicals of the crude extract, like the phenolic and ascorbate extracts, decreased significantly with increased maturation. The changes were strongly correlated with the content of total phenolics and ascorbic acid. Antioxidant capacity of the lipophilic extract increased significantly and corresponded to the increase in total carotenoids. The phenolic fractions made a major contribution to the total antioxidant capacity due to the high content of total phenolics. The lipophilic fractions were most effective if the comparison was based on the ratio between antioxidant capacity and content of antioxidants. The crude extract of fruits showed the highest inhibitory effect in both 2,2-azobis(2,4-dimethylvaleronitrile) (AMVN) and ascorbate-iron induced lipid peroxidations. The aqueous and ascorbate-free extracts showed higher inhibition in the AMVN assay, but lower inhibition in ascorbate-iron induced peroxidation, than the lipophilic extract.     

Processing effects on the composition of sea buckthorn juice from Hippophae rhamnoides L. Cv. Indian Summer.

Sea buckthorn juice is one product that can be derived from the sea buckthorn berry, a new alternative crop for the Canadian western provinces. Fresh pressed juice separates into three phases when allowed to stand overnight in the refrigerator: an upper cream phase, juice in the middle portion, and a sediment at the bottom. Enzymatic hydrolysis with commercial, broad spectrum carbohydrate hydrolyzing enzyme preparations reduced the juice viscosity, assisted juice separation, and provided an opalescent juice. Soluble solids averaged 10.2 degrees Brix, pH averaged 3.13, ascorbic acid averaged 174.2 mg/100 mL, and titratable acidity averaged 1.97% as malic acid all determined on centrifuged (10 000 rpm, 15 min) juice. Soluble sugars included glucose, fructose, and an unidentified component that was not sucrose or other common soluble monomeric or dimeric sugar. Quinic acid was quantitatively most important, while malic was next, and oxalic, citric, and tartaric acids were minor components. Washing berries by dipping reduced soluble solids (degrees Brix) in juice suggesting uptake of wash water.     

Influence of harvest time on the quality of oil-based compounds in sea buckthorn (Hippophae rhamnoides L. ssp. sinensis) seed and fruit

The effect of the harvest time on oil-based bioactive compounds in sea buckthorn berries ( Hippophae rhamnoides L. ssp. sinensis) was investigated. Sea buckthorn berries were collected at early maturity (September), maturity (November), and postmaturity (January) during the 2003-2004 harvest year. Whole berries were analyzed for physical characteristics, and fruit and seed fractions were analyzed for bioactive content. November-harvested berries yielded the highest values for berry sizes, CIELab factor a*, and total carotenoid content in the fruit fraction ( p < 0.05). September yielded significantly higher ( p < 0.05) levels of major compounds, alpha-tocopherol and beta-sitosterol, in the fruit fraction. Seed characteristics and bioactive compounds did not vary significantly with respect to the harvest time ( p > 0.05). These results have identified the most suitable level of maturity for the optimization of certain compounds and the losses that may occur with winter harvest, commonly practiced in cold climates.     

Phytosterols in sea buckthorn (Hippopha? rhamnoides L.) berries: identification and effects of different origins and harvesting times.

Sterols in seeds, pulp/peel fractions, and whole berries of sea buckthorn (Hippopha? rhamnoides L.) samples belonging to two major subspecies (sinensis and rhamnoides) from Finland and China were analyzed as TMS derivatives by gas chromatography-mass spectrometry after saponification of the oils. The total sterol contents in the seeds, the fresh pulp/peel, and the whole berries were 1200-1800, 240-400, and 340-520 mg/kg, respectively. The corresponding values in the extracted oils were 12-23, 10-29, and 13-33 g/kg. Sitosterol constituted 57-76 and 61-83%, respectively, of the seed and pulp/peel sterols. The sterol content and composition showed little variation between subspecies and collection sites. Different harvesting dates showed significant effects on the levels of some sterols both in the seeds and in the pulp/peel. The sterol profiles obtained are useful for characterizing sea buckthorn and detecting adulterations of the valuable oils. The information provided by the present investigation is also important for further chemical investigation of sea buckthorn sterols and industrial utilization of the berries as a raw material of functional foods.     

基于空间差异的新疆沙棘资源果实品质及营养成分分析

为研究空间分布差异性对新疆沙棘资源果实品质及营养成分的影响。以5个县的‘深秋红’‘无刺丰’‘状圆黄’沙棘品种为供试样本,并对供试样本的可溶性固形物、蛋白质、氨基酸、总糖、总酸、维生素C、微量元素、总黄酮、脂肪酸、花青素、β-胡萝卜素、番茄红素含量测定,后进行主成分分析并计算综合得分。13个供试沙棘样品果实中各营养及药用成分均存在不同程度的差异性。青河县沙棘果实综合测试指标比布尔津县综合高出0.93～5.54倍,比哈巴河县综合高出0.90～4.49倍,比乌什县综合高出0.99～13.67倍,比阿合奇县综合高出1.10～4.98倍。青河县沙棘品种‘状圆黄’果实各项品质指标表现最优,综合得分为6.04分;且青河县沙棘资源整体综合得分最高,平均为3.54分。青河县更适宜沙棘的生长发育,种植的沙棘果实品质更为优异,13个供试沙棘样品中青河县‘状圆黄’果实品质最佳。     

饲用型沙棘引种试验

自内蒙古磴口引进三个优良沙棘品种的苗木,进行为期7年多的引种观测试验。对植株生长量、产叶量物候期等进行定点长期观测,并对枝条、叶片的营养成分进行检测,综合分析认为:草新2号适应性强,生长量较大,枝条无刺,营养成分含量高,是宁夏地区优良的饲用型沙棘品种。     

不同类型沙棘人工林对土壤氮矿化速率的影响

采用离子交换膜埋植培养法,对陕西省永寿县马莲滩流域沙棘纯林、沙棘×刺槐、沙棘×侧柏、沙棘×油松四种类型林分不同深度土壤的氮矿化速率进行了研究。结果表明,用离子交换膜从土壤中提取出的氮量随着其培养时间的增加而增加,且与土壤全氮含量、碱解氮含量及土壤磷酸酶活性三个土壤肥力指标呈极显著相关,培养30 d所得氮矿化速率与这三个土壤肥力指标的相关系数达到了0.850、0.857和0.736,此方法可用来较准确测定土壤的氮矿化速率;经测定,四种类型沙棘人工林氮矿化速率大小顺序为:沙棘纯林>沙棘×油松>沙棘×刺槐>沙棘×侧柏。     

不同温度条件下沙棘雄株花粉储存时间研究

为研究不同温度条件、不同储存时间对沙棘雄株花粉生活力的影响,采用蓝墨水染色法对分别保存在20～22℃室温和4℃低温条件下的沙棘雄株花粉离体后的生活力进行了测定。结果表明:室温下无刺雄花粉存活时间最短,活性下降速度最快,离体5～11 d下降速度达到峰值,中雄花粉存活时间最长,活性下降速度最慢,11～15 d下降速度到达峰值,以花粉生活力50%为下限,阿列伊与201306可以存活9 d,中雄可以存活11 d,无刺雄存活7 d;4℃低温条件下,阿列伊花粉存活时间最长,为17 d,活性下降速度最慢,在离体15～21 d时下降速度达到峰值,无刺雄花粉存活时间最短,为9 d,活性下降速度快,在5～11 d时下降速度达到峰值,中雄与201306花粉存活时间分别为13、11 d。     

砒砂岩区沙棘人工林的萌蘖能力

为了达到快速治理砒砂岩区的目的,采用标准地调查方法,对内蒙古区鄂尔多斯市准格尔旗准格尔召镇近年来营造的不同林龄沙棘林萌蘖能力进行研究,以期对沙棘种植的设计、施工以及管理等提供依据。结果表明：沙棘具有极强的萌蘖性能,定植株2-8 a的沙棘人工林分,其萌蘖能力为0.2万-8.0万株/hm^2;沙棘萌蘖能力随林龄的变化,在2-4 a逐渐增加,5-6 a时达到最高,之后7-8 a又逐步下降;萌蘖能力以水、肥等条件最好的沟谷地川滩地最高,平均可达2.1万株/hm^2;不同立地条件类型间,萌蘖能力相差超过1倍;中等盖度（40%-70%）的沙棘人工林分,其萌蘖能力最高。生产实践中可充分利用沙棘萌蘖能力强的优势,适度降低种植密度,有效减少苗木和种植成本,从而实现砒砂岩区快速、经济、高效恢复植被、根治严重水土流失的目的。     

沙棘在伊金霍洛旗矿区农林复合生态系统中的应用

沙棘(Hippophae rhamnoides L.)具有极强的生态防护功能,是我国造林绿化、国土整治和建立完备的农林生态系统的主要先锋树种,还有较高的经济效益,因此被广泛用于伊金霍洛旗矿区农林复合生态系统当中,形成了与当地自然环境相适应的复合生态系统.随着高科技的发展,沙棘的种类不断增多,其在伊金霍洛旗矿区农林复合生...     

砒砂岩区种植沙棘后景观格局变化预测

沙棘是砒砂岩区沟谷部位常用的一种生态恢复树种。通过运用马尔科夫模型,对种植沙棘后砒砂岩区景观格局变化趋势的分析,预测沙棘等各类景观要素的发展规模,以为科学指导类似沙棘生态工程的建设项目提供相关依据。为探索种植沙棘对景观系统的影响,将沙棘单独分出来作为一种景观类型,与其他常规景观类型一起进行景观格局分析。结果表明:在砒砂岩区,沙棘生态工程建设是对区域景观生态格局变化影响最大的因素;预测确定的砒砂岩区沙棘种植面积的最大比例为10.21%,乔木林地面积比例预测值在10%以下,林地面积过大将会造成土壤干层下移,最终可能导致大片林分死亡现象出现;稀疏植被地的面积稳定比例为32.25%,在干旱少雨的砒砂岩区,较高的稀疏植被比例,是适应当地环境条件的最佳选择。     

我国沙棘资源建设与开发的成效和经验

沙棘（Hippophae rhamnoides）资源建设与开发在我国“三北”地区具有十分重要的意义。通过对20多年来这一工作的总结分析,发现目前的辉煌成效主要得益于历任中央领导的高度重视、国家有关部门的密切协作配合以及专门机构的共同推动。通过对沙棘资源建设与开发进行展望,指出需要针对目前存在的瓶颈问题,设立专题开展研究,并加强国际合作,才有可能加快沙棘资源建设步伐,稳步提高沙棘综合开发效益,为建设和谐社会服务。     

树脂法精制沙棘籽原花色素的研究

为纯化沙棘原花色素,本文对16种不同类型树脂进行沙棘原花色素静态吸附试验、动态吸附和解吸性能的比较,筛选出对沙棘原花色素有较好分离纯化效果的4种树脂,比较不同洗脱级分中原花色素的含量,最后筛选出D3520大孔树脂为符合提纯要求的最适合的树脂;采用该树脂,用30%乙醇洗脱,原花色素产品纯度达96.5%,得率为30.4%。     

超声波微波协同提取沙棘叶黄酮及其组成和活性研究

沙棘叶中富含黄酮类化合物等多种活性成分,为提高其提取率和利用率,本研究采用常规溶剂萃取、超声辅助、微波辅助、超声波微波协同提取4种方法对沙棘叶黄酮进行提取,测定沙棘叶黄酮得率并观察沙棘叶的微观组织结构,比较筛选沙棘叶黄酮的最佳提取方法。并采用响应面法对最佳提取方法进行工艺优化,同时测定沙棘叶黄酮组成和体外抗氧化活性。结果表明,超声波微波协同提取法是提取沙棘叶黄酮的最佳方法,黄酮得率较常规溶剂萃取法提高了42.54%(P<0.05),沙棘叶细胞损伤最严重。超声波微波协同提取沙棘叶黄酮的最佳工艺为乙醇体积分数61%、提取时间18 min、微波功率446 W,此时黄酮得率为42.09 mg·g^-1。沙棘叶黄酮提取液中共鉴定出6种黄酮类成分,分别为儿茶素、丁香酸、山萘酚、槲皮素、异鼠李素、杨梅素,其中儿茶素含量最高,为1.474 8 mg·g^-1,其余5种的含量均在0.1~0.3 mg·g^-1之间,山萘酚最低,为0.125 2 mg·g^-1;沙棘叶黄酮提取液具有较强的还原力及较高的1,1-二苯基-2-三硝基苯肼(DPPH)、2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸(ABTS)和羟基自由基清除率,抗氧化活性较高。本研究为沙棘叶黄酮的工业化生产提供了科学依据。     

地表凋落物对油松、沙棘人工林土壤呼吸的影响

通过对黄土丘陵区油松、沙棘人工林自然组(含凋落物)和去凋组(不含凋落物)土壤呼吸、5cm土壤温度和含水量的监测,研究地表凋落物对土壤呼吸的影响。在两种林分内分别设置20m×20m样地,样地内随机设置5个观测点,于2015年6月到2016年5月使用LI-8100系统进行监测。结果表明:(1)自然组油松林和沙棘林土壤呼吸季节动态及日动态均表现为单峰型变化曲线,沙棘土壤呼吸年均值[2.10μmol/(m~2·s)]显著高于油松[1.56μmol/(m~2·s),p0.05];去除凋落物后,两种林分土壤呼吸与自然组具有相似的季节及日动态特征,但土壤呼吸年均值不存在显著性差异。(2)沙棘林自然组土壤呼吸年均值显著高于去凋组[1.58μmol/(m~2·s),p0.05],凋落物呼吸对土壤总呼吸的贡献率为15.81%;油松林自然组与去凋组土壤呼吸年均值差异不显著,凋落物呼吸对土壤总呼吸的贡献率仅为1.61%。(3)自然组和去凋组中油松、沙棘林土壤呼吸与温度均存在显著指数关系(p0.05),与含水量则存在显著线性负相关关系(p0.05);两组处理土壤温度和含水量对土壤呼吸的单独解释量均较低(0.05%~37.82%),土壤呼吸主要受到温度和含水量共同作用的影响(8.01%~66.44%)。地表凋落物显著提高了沙棘林土壤呼吸的Q10和土壤呼吸量,但仅显著提高了油松林的Q10,对土壤呼吸量并未显著增加。油松林作为黄土丘陵区水土保持及生态恢复的造林树种更有利于该地区林地碳汇功能的提升。     

Variation of Vitamin C Concentration and Character Correlation between and within Natural Sea Buckthorn (Hippophae rhamnoides L.) Populations

Abstract

To study the variation of vitamin C concentration between and within populations and genotypes, 701 berry samples from 71 bushes representing 10 Finnish populations of Hippophae rhamnoides were analysed. The vitamin C concentration varied from 28 to 201 mg/100 g of berries among bushes, from 60 to 122 mg among the populations. Significant differences were found between genotypes and populations, indicating that vitamin C concentration is under genetic control. Though it was significant, the correlation between vitamin C concentration and berry size was very weak (r = -0.316). The results indicated that it should be possible to improve the two characters by simultaneous selection.     

Synthesis of resins with ionic liquids for purification of flavonoids from Hippophae rhamnoides L. leaves

The efficient purification method of high-purity flavonoids from Hippophae rhamnoides L. (sea buckthorn) is reported. A novel room temperature ionic liquid-based macroporous adsorption resin (MAR), N-methylimidazole/MARs (Mim/MARs), was prepared on the basis of the Friedel-Crafts-catalyzed and surface-modified technique. The material exhibited favorable characteristics for adsorption application, including high pore volume (1.90 cm(3)/g, 3 times as big as the optimal commercial adsorbent), good pore structure (type IV isotherm with an H1 hysteresis loop, the most favorable structure for adsorption purposes), narrow particle size and pore size distribution (1.2 mm with a standard deviation of 0.106 mm), and excellent chemical stability. This paper also presents the first experimental evidence that the functional groups of the modified materials and composite action of certain molecular interactions between the adsorbent and flavonoids affected the adsorption process. Moreover, a new sphere-size adsorption kinetics model in which the adsorption process contained three or more compartments and detailed parameters of sphere size was developed according to the multicompartment kinetics model and Karichhoff's theory by investigating the regression of the experimental results. The conclusion that the first compartment of the adsorption process onto Mim/MARs mainly occurred on spheres larger than 0.83 mm and the second and third ones mainly occurred on spheres of 0.46-0.83 and 0.22-0.46 mm, respectively, was drawn from this new sphere-size adsorption kinetics model.