万寿菊花中叶黄素酯的提取及皂化工艺

叶黄素具有调节人体的免疫能力、防治老年性视黄斑退化和白内障等作用,目前天然叶黄素的提取原料主要为万寿菊花,万寿菊花的有机溶剂提取物含有大量叶黄素酯,经皂化后可转变为叶黄素,广泛用于食品、食品添加剂、药品及饲料等工业.本文采用甲醇处理万寿菊鲜花后直接用正己烷提取叶黄素酯,并通过L9 (34)正交实验选择了叶黄素酯皂化的最佳条件,即KOH/甲醇浓度为20%,提取液﹕KOH为4 : 1,时间为40min,温度为50℃时,叶黄素酯皂化进行的比较完全.皂化得到的叶黄素在丙酮﹕甲醇(v : v)为1 : 1的混合溶剂中进行重结晶,得到叶黄素晶体,纯度为97.2%.     

游离态叶黄素和玉米黄素体外单线态氧淬灭率的比较研究

为比较玉米黄素和叶黄素单体的体外淬灭单线态氧能力,本实验分别萃取万寿菊与枸杞中的叶黄素与玉米黄素酯,经皂化和纯化后得到游离的叶黄素与玉米黄素组分。使用C30-HPLC-PDA 分别对制备组分进行定性和定量分析。用次氯酸钠-双氧水反应产生单线态氧,使用微弱发光测量仪测定制备组分对单线态氧的淬灭率。结果显示：游离叶黄素和玉米黄素均能减少次氯酸钠-双氧水反应体系产生的单线态氧数量,导致最大光子计数值下降。二者淬灭单线态氧的能力相似,最小作用剂量均为0.005～0.05 g/L。     

万寿菊干花颗粒中叶黄素酯的超临界CO2萃取初探

从万寿菊花中萃取叶黄素酯是制备叶黄素过程中的重要技术。本项研究对叶黄素酯的超临界CO2萃取进行了初步探索。实验结果表明,提高萃取压力、减小样品颗粒粒径以及减小萃取介质的极性均可增加叶黄素酯的萃取率。今后如果能在破坏叶黄素酯与花瓣组织介质的关联程度和降低萃取介质极性两个方面取得进展,超临界流体萃取有可能成为一种可应用于叶黄素酯萃取的技术。     

叶黄素酯在体内的相对生物利用度评价

本研究的目的是以叶黄素单体的值为参比测定叶黄素酯在体内的相对生物利用度。在实验中,分别一次灌胃雄性SD 大鼠叶黄素酯和单体,应用C18-HPLC 方法,测定二者在血清中的代谢情况,根据二者在血清中积累水平的峰值,以叶黄素单体的值为参比,计算叶黄素酯的相对生物利用度。实验结果表明：叶黄素酯的相对利用度为18.55%。这一结论有助于客观地评价叶黄素酯在食品中应用的可能性。     

叶黄素单体与酯的生物接近度比较

本项研究的目的是通过测定叶黄素和叶黄素酯在大鼠体内的排泄率来比较二者的生物接近度（Bio-accessibility）。在实验中,首先从万寿菊干花颗粒中制备叶黄素和叶黄素酯,随后分别灌胃到雄性SD大鼠中,用紫外-可见光分光光度法测定大鼠24小时内粪便中二者的排泄率。实验结果表明：叶黄素的排泄率较叶黄素酯高。根据这一结果,可以判断叶黄素酯的生物接近度较叶黄素高。     

烘焙类食品中叶黄素酯提取及检测方法建立

为检测烘焙类食品中的叶黄素酯以及筛选无乙醚的萃取溶剂,本文对烘焙产品中的叶黄素酯皂化时间、KOH浓度以及不同萃取溶剂的萃取效果进行研究。结果表明检测烘焙食品中叶黄素酯的皂化最优条件为:2 g样品（面糊/面团）,0.2 g BHT,10 mL无水乙醇,10 mL 60 g/100 mL KOH水溶液,室温振荡3 h。萃取溶剂环己烷:正己烷:乙酸乙酯=1:2:2为最佳萃取剂,回收率为94.31%~103.83%,精密度实验相对标准偏差均小于5%。表明该方法适合于烘焙类食品中叶黄素酯的提取及检测。     

叶黄素

叶黄素义名“植物黄体素“属于“类胡萝卜素“族物质，是一种广泛存在于蔬菜、花卉、水果和某些藻类生物中的天然色素。国外研究发王见，叶黄素在甘蓝、羽衣甘蓝、菠菜等深绿色叶菜以及金盏花、万寿菊等花卉中含量最高。其次，南瓜、桃子、辣椒、芒果、柑橘中则富含丰富的“叶美素酯”，它是叶黄素的前体物质。叶黄素酯水解为游离叶黄素后才被吸收和代谢。     

温度控制对微波萃取叶黄素酯的影响

探索温度控制对微波辅助萃取叶黄素酯萃取率的影响。首先测定不同输出功率对萃取溶媒升温的影响,然后以万寿菊干花颗粒为样品,探讨升温功率、萃取时间和萃取温度对萃取率的影响,并比较相同温度条件下微波萃取与溶剂法的萃取率。结果表明：分子中含有O－H键的溶媒升温较快;升温功率的变化对萃取率的影响有限。萃取时间的延长可导致萃取率下降;在1600W、20min和分别为50、50、40℃条件下,正己烷、乙酸乙酯和四氢呋喃萃取率分别为83%～95.23%、81.44%～96.59%和91.72%～94.40%。在相同温度条件下,微波萃取可有效地提高叶黄素酯的萃取率。     

万寿菊干花中叶黄素酯的超声提取工艺研究

研究了超声提取万寿菊干花中叶黄素酯的工艺条件,分别考察了不同溶剂、料液比、超声功率和超声时间对叶黄素酯含量的影响.结果表明:采用正己烷为溶剂,料液比1:30,超声功率500W,超声时间40min为最佳条件,此时叶黄素酯的含量达到15.5mg/g.     

宏基因组文库脂肪酶提取分离叶黄素晶体的工艺研究

以万寿菊油树脂为原料,采用源于宏基因组文库脂肪酶处理,有机溶剂萃取的方法提取叶黄素,研究优化此过程的工艺条件。实验表明:万寿菊油树脂的最适溶解介质为乙醇溶液,宏基因组文库脂肪酶的添加量为万寿菊油树脂的2.0%,水解时间为12min,水解温度为50℃,液料比7v/m,提取温度40℃。对此工艺进行验证叶黄素提取率可达94.8%,收率为84.6%;总类胡萝卜素的含量为87.2%,其中含全反式叶黄素91.2%,全反式玉米黄质5.6%。与普通酶法提取叶黄素的方法相比较,本研究所采用的宏基因文库脂肪酶的效率更高,制备的叶黄素含量和收率更高,此方法明显优于普通酶法。     

叶黄素的体外抗氧化功能

应用反相高压液相色谱(RP HPLC)从万寿菊的花中制备叶黄素的反式(E )、顺式(Z )异构体及其酯类3个组分。然后,应用微弱发光检测技术测定和比较各组分在体外淬灭单线态氧的能力。结果表明,反式和顺式叶黄素及其酯类均有体外淬灭单线态氧的能力,同时,还可观察到顺式异构体的“延迟发光”现象,说明反式异构体与顺势异构体可能有不同的淬灭单线态氧的机理     

C30柱分离万寿菊花中的叶黄素类化合物初探

应用C30-HPLC-PDA,万寿菊花萃取物中的叶黄素类化合物获得了良好的分离,包括:叶黄素酯的分离和单体几何异构体的分离。色谱条件为:WatersYMCCarotenoidS-5(4.6×250mm)柱;乙腈-甲醇(75:25,V/V)为流动相A,甲基叔丁基醚为流动相B,线性梯度洗脱;流速:1.0ml/min;PDA波长范围:300～600nm;进样量:20μl。根据各组分的色谱行为、光谱特征和在碘催化下发生几何异构的产物分析对各组分进行初步鉴定。实验结果显示:C30固定相在分离万寿菊花萃取物中的叶黄素类化合物的应用中有良好的前景。     

微藻产叶黄素研究进展

叶黄素是一种对人体健康有益的天然类胡萝卜素,目前工业提取主要来源于万寿菊等植物。因生长周期短、叶黄素含量相对较高等优势,海洋微藻成为叶黄素生产的潜力来源之一。文章综述近年来高产叶黄素藻种、提高叶黄素产量代谢调控策略、叶黄素提取工艺以及功能活性等研究进展,为推动微藻叶黄素早日实现工业化生产提供理论参考。     

A Simple and Selective Analytical Procedure for the Extraction and Quantification of Lutein from Tomato By-Products by HPLC–DAD

Lutein, a yellow dihydroxylated carotenoid, is present in many dietary supplements due to its biological properties. Currently, lutein is extracted from marigold flowers by expensive and time-consuming processes. Since tomatoes contain significant levels of lutein, in this study we have examined the feasibility of using tomato by-products as an alternative, low-cost source of this carotenoid. The determination of this carotenoid was performed by high-performance liquid chromatography–diode array detection, after selective extraction from tomato waste product samples. Lutein levels ranged from 9.9 to 10.5 μg/g dry weight. Tomato waste products may be indicated as an alternative commercial source of lutein for food fortification and/or dietary supplements.     

制备万寿菊叶黄素技术研究进展

由于叶黄素(lutein)是自然界广泛存在的二羟基类胡萝卜素,也是人眼视网膜黄斑色素主要组成部分。叶黄素可有效预防并辅助治疗老年性黄斑退化病和白内障等眼部疾病,其在生物活性物质利用领域有广泛的应用前景。万寿菊是工业上提取分离叶黄素的理想工业原料。本文从万寿菊叶黄素提取专用品种、叶黄素分子结构及叶黄素稳定性等6个方面综述了近年来国内外有关万寿菊叶黄素的研究工作,并进行了前景展望。     

万寿菊叶黄素提取分离研究

本文研究了由万寿菊提取叶黄素的条件,包括皂化处理NaOH浓度,提取时间与次数对提取效率的影响,并通过薄层层析对产品进行了分析。     

Lutein and zeaxanthin in new dietary supplements—analysis and quantification

Lutein and zeaxanthin, two xanthophylls supposed to delay formation of age-related macular degeneration (AMD), are found in numerous new dietary supplements appearing on the international market. Usually, the lutein concentration ranges from 0.25 to 20 mg/serving size. The lutein contents of 14 products with lutein highlighted on the label were evaluated. Oily formulations were dissolved, and powdery capsule contents were extracted with solvents before high-performance liquid chromatography (HPLC) analysis (diode-array detector, 450 nm) using a C30 column. If lutein diesters from marigold (Tagetes erecta) were present, the extracts were saponified with methanolic KOH. To unequivocally identify carotenoids, HPLC-(atmospheric pressure chemical ionization)mass spectrometry was applied. In this study only all-trans-lutein was quantified, whereas cis isomers (approximately 1–5 area% of total lutein) were not taken into account. The lutein concentration of half of the products investigated was found to be below the amount stated, varying here from 11 to 93%. With the exception of one product, all dietary supplements contained zeaxanthin in amounts typical for the use of marigold oleoresin (6.0±1.4 area% of all-trans-lutein). The high discrepancy found between the amounts labeled and determined in half of the products may be attributed to degradation reactions or to improper storage conditions.     

Storage stability of lutein during ripening of cheddar cheese

Lutein (3,3'-dihydroxy-alpha-carotene) has been identified as a dietary factor that can delay the onset of age-related macular degeneration (AMD). However, available food sources of lutein contain only modest amounts of the carotenoid. Food fortification with lutein extract has been identified as a low-budget approach to prevent the onset or progression of AMD. The objectives of this study were to 1) incorporate various amounts of lutein into Cheddar cheese; 2) examine the color, pH, microbiological, and sensory characteristics of the Cheddar cheese during storage; and 3) analyze the stability of lutein during the cheese maturation process. Lutein extracted from corn was added to Cheddar cheese in quantities of 1, 3, and 6 mg per serving size. Measurements of the lutein stability were carried out by HPLC using a YMC C30 carotenoid column. Microbiological analyses of cheese samples included aerobic plate count, coliform, and yeast/mold counts. The color attributes a* and b* were significantly different between the treatment and control groups; however, no significant difference was observed in L* value and pH. Significant differences among 1, 3, and 6 mg lutein-enriched cheeses were observed in the aerobic plate count and yeast/mold compared with the control. Cheese samples contained no detectable levels of coliforms (< 10 cfu/g). The HPLC data showed quantitative recovery of lutein during the storage period, and no lutein degradation products were identified. These results indicate that lutein, a functional additive with purported ability to prevent or reduce the onset of AMD, can be incorporated into cheese adding value to this product.