千日红色素的提取及稳定性研究

目的 研究千日红天然色素的提取及稳定性.方法 采用蒸馏水,用减压蒸馏法从千日红中提取了天然色素.结果 该色素在酸性条件下较稳定;在一定的温度范围内(40℃以下)稳定;强光下在一段时间内稳定;抗坏血酸、葡萄糖、蔗糖、淀粉、柠檬酸,几种金属离子对该色素无不良影响.结论 该实验方法具有良好的重复性,可靠性,千日红色素是一种较好的天然植物色素资源.     

科学用色素

色素又叫食品着色剂,是在制作或烹调食物时所添加的对人体健康无。害的一种制作颜料。它可以增加食品的美观,还可以促进人们的食欲,五颜六色的糖果糕点还有各种饮料,都少不了食用色素的功劳。 食用色素分为天然食用色素     

田基黄色素的提取及其稳定性

目的:探讨不同溶剂提取田基黄色素的方法,并考察各种因素对色素稳定性的影响.方法:采用6种不同溶剂提取色素,测试pH、温度、光熙、还原剂及氧化剂等因素对色素稳定性的影响.结果:田基黄色素用95％乙醇30℃超声提取10 min效果最佳,该色素在光照、强酸碱性、Mg2+、Al3+等条件下不稳定,食品添加剂、还原剂、氧化剂对色素的稳定性影响不大.结论:该色素具有较好稳定性,但须防止光照,避免酸碱性条件下使用.田基黄色素可作为一种较好的天然植物色素资源.     

健康，市场皆强烈呼唤天然食用色素

食用色素又称着色剂,是一类本身具有色泽,以使食品着色为目的的食品添加剂。按其来源和性质,可分为食用天然色素和食用合成色素两大类。食用天然色素主要来自动、植物组织或微生物代谢产物。植物色素有β-胡萝卜、叶绿素铜钠盐、姜黄等;动物色素有虫胶色素等;微生物色素则可分为类胡萝卜素、卟啉类色素、酮类色素、醌类色素,以及β-花青素、黄素类色素等等。此外,食用天然色素还包括一部分无机色素,但一般毒性较大,很少应用。长期实践证明,天然色素多数比较安全,能较好地模仿天然物的颜色,有些还具有一定的营养价值(如β-胡萝卜素、核黄素),…     

市场呼唤天然食用色素

天然食用色素有较高的实用价值和经济价值。天然食用色素既可以使食品具有鲜艳的颜色,以增加食欲而且使用较安全,色调自然。其缺点是:色谱不全,着色力低,稳定性差,提     

远离鲜艳食品

正市场上颜色鲜艳的食品特别受小朋友们的青睐。不过我得提醒家长朋友们,在满足孩子需求时一定要注重食品安全,不要过分追求外观鲜艳、好看的儿童食品。据了解,食品的彩衣是由色素制成,色素分为天然色素和人工合成色素两类。天然色素从动植物中提取,是一种安全、理想的食用色素,但来源较少,价格又高,使用并不广泛。而人工合成色素     

你知道五彩食品有害吗?

人有化妆品,食品也有化妆品,它的名字叫“食品色素”。食品加了色素,好看、漂亮,惹人垂涎,诱人进食。尤其在夏季,街摊上各种色彩鲜艳的清凉饮料,吸引着过往的少年儿童。光看到好看,其背后的害处却很少有人警惕。 食用色素分天然食用色素和合成食用色素。天然色素是从动、植物中提取的,有虫胶色素、姜黄素、红花     

液液分配色谱及其与液相色谱联用分离天然花色苷的研究进展

液液分配色谱（liquid-liquid partition chromatography,LLC）是一种连续高效的分配色谱技术,如今已广泛应用于天然产物领域。天然花色苷是一种黄酮类天然色素,具有多种生理活性。花色苷极不稳定,LLC因其具有操作条件温和、可避免样品不可逆吸附等特点目前已广泛应用于天然花色苷的制备性分离。综述了2010—2019年LLC及其与液相色谱联用（liquid-liquid partition chromatography-liquid chromatography,LLC-LC）分离纯化天然花色苷的研究进展。     

影响陈皮色素稳定性的因子研究

目的:为生产各种食用品、化妆品、医药药品等色素新产品提供重要原料,研究陈皮色素的提取条件和稳定性.方法:以水为提取剂,用紫外分析法研究陈皮色素的稳定性.结果:以水为提取剂,料液比为1:80,在室温下浸提24h.结论:色素在330nm处有最大吸收峰,该色素水溶性较好,强碱性物质对该色素稳定性有一定影响,但热稳定性良好.苯甲酸钠、柠檬酸、醋酸、蔗糖、葡萄糖、可溶性淀粉等食品添加剂对陈皮色素稳定性无明显影响.氧化剂、还原剂中除抗坏血酸对色素的影响明显外,其他均无明显影响,金属离子对其影响较小.     

常吃紫色食物让女人更靓丽

紫色蔬果不仅看起来漂亮,而且还具有很高的营养价值。植物类紫色食品的色素均由“花色素”类物质构成。“花色素”被称为最出色的天然抗氧剂,其抗氧化作用分别为维生素C、维生素E的30倍和50倍,能让女人保持青春靓丽。女性朋友们还等什么,学做紫色料理吧,让我们马上收获美丽与健康。     

Antioxidant profiles of a prepared extract of Chinese herbs for the treatment of atopic eczema

A standardized mixture of Chinese herbs, Zemaphyte taken orally as a daily decoction has been shown to be effective in the treatment of atopic eczema. This study showed that Zemaphyte is an efficient antioxidant, being capable of scavenging both superoxide and hydroxyl, and preventing peroxidation of biological membranes. It does not degrade hydrogen peroxide directly, but instead most likely forms a Zemaphyte-hydrogen peroxide complex. The complexed hydrogen peroxide can then be degraded in the presence of catalase to form oxygen and water. It is conceivable that Zemaphyte may contribute to the down-regulation of the activities of cells implicated in atopic eczema through its antioxidant activities.     

莱菔硫烷抑制氧化应激下人视网膜色素上皮细胞凋亡

目的：观察仅莱菔硫烷（SFN）对外源性H2O2诱导的人视网膜色素上皮细胞ARPE-19细胞凋亡的影响，并探讨其可能的分子机制。方法：体外培养人视网膜色素上皮细胞系ARPE-19细胞，用12．5mmol／L外源性过氧化氢（H2O2）作用30min后，再加入不同浓度SFN作用不同时间。流式细胞术检测ARPE-19细胞凋亡，RT—PCR和Westernblot分别检测H0-1mRNA和蛋白的表达。同时分别采用HO-1的激动剂CoPP和抑制剂ZnPP处理细胞，观察细胞凋亡的变化。结果：SFN处理ARPE-19细胞后，可显著诱导其表达H0—1mRlqA和蛋白，并呈一定的剂量依赖性。同时，H2O2处理后能显著诱导ARPE-19细胞产生ROS，而经不同浓度SFN处理后，ROS产生显著降低。结论：α—硫辛酸诱导氧化应激下人视网膜色素上皮细胞表达H0-1，从而抑制ROS的过度产生。     

二色补血草多糖脱色工艺研究

目的:对二色补血草多糖进行脱色研究,筛选最优的脱色方法。方法:采用活性炭法、双氧水法、大孔树脂法,反胶束法对二色补血草多糖进行脱色研究。结果:双氧水法是一种相对优化的脱色方法,工艺条件为:温度55℃,时间2 h,pH值=8.5,样液比1.5,实验结果,多糖色素脱除率:87.75%,多糖保留率:87.97%。结论:双氧水法是一种最好的脱色方法。     

Genotoxic and Antigenotoxic Activity of Acerola (Malpighia glabra L.) Extract in Relation to the Geographic Origin

Malpighia glabra L, popularly known as acerola, is considered a functional fruit and therefore is taken to prevent disease or as adjuvant to treatment strategies, since the fruit is an undeniable source of vitamin C, carotenoids, and flavonoids. Acerola is a natural source of vitamin C, flavonoids, and carotenoids. Its chemical composition is affected by genetic uniformity of the orchards and environmental factors. Considering the extensive growth of the culture of acerola in Brazil as well as its widespread use, this study evaluates the genotoxic and antigenotoxic activity of acerola in relation to geographical origin using the comet assay in mice blood cells in vitro. No acerola samples showed potential to induce DNA damage, independently of origin. Also, for antigenotoxicity activity, only the acerola sample from São Paulo reduced DNA damage induced by hydrogen peroxide (by about 56%). The sample from Ceará showed good antioxidant activity by the 2,2‐diphenyl‐1‐picrylhydrazyl assay, in agreement with its higher rutin, quercetin, and vitamin C levels. Additional studies with other treatment regimens are necessary to better understand the impact of the complex mixture of acerola on genomic stability. Copyright © 2012 John Wiley & Sons, Ltd.     

纳米铁和褪黑素对驯化栽培条件下甘肃贝母产量和品质的影响

目的:研究纳米铁和褪黑素对栽培甘肃贝母产量和品质的影响,为驯化栽培提供技术支撑。方法:常规方法称量百粒重;2020年版《中华人民共和国药典》方法检测生物碱含量;分光光度法检测叶绿素、过氧化氢、丙二醛含量及超氧化物歧化酶(SOD),过氧化物酶(POD),过氧化氢酶(CAT)活性;超高效液相色谱串联质谱法检测生长素、细胞分裂素、赤霉素、水杨酸、茉莉酸、脱落酸含量。结果:在不影响品质的前提下,纳米铁和褪黑素处理显著提高了百粒重,对不同时期生理生化指标的影响显著,对内源激素含量的影响基本一致。相关性分析表明百粒重与SOD活性、丙二醛、茉莉酸含量成负相关,与POD活性、水杨酸、赤霉素、生长素、脱落酸含量成正相关;主成分分析能够将两种处理有效分开,表明其促生机制存在一定差异,纳米铁处理主要影响生长素、水杨酸、脱落酸;褪黑素处理主要影响SOD,丙二醛,赤霉素。结论:纳米铁和褪黑素可以作为一种简单的实用技术提高栽培甘肃贝母抗逆性和产量。     

The antioxidant potential of Sutherlandia frutescens

One of the best-known multi-purpose medicinal plants in Southern Africa, Sutherlandia frutescens subsp. microphylla (family: Fabaceae/Leguminosa), is used for a wide range of conditions, including cancer, viral diseases and inflammatory conditions. Little scientific data has been documented on the mechanism by which Sutherlandia frutescens acts on the immune system. Phagocyte derived reactive oxygen species, such as hydrogen peroxide and superoxide radicals, are responsible for the pathogenesis of various inflammatory conditions. Anti-inflammatory properties of various medicinal-plant extracts have been explained, at least in part, by their antioxidant activities. We investigated the effects of a hot water extract of Sutherlandia frutescens on both luminol and lucigenin enhanced chemiluminescence of neutrophils stimulated with L-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) as well as its superoxide and hydrogen peroxide scavenging properties in a cell free system. The results indicate that Sutherlandia frutescens extract possesses superoxide as well as hydrogen peroxide scavenging activities at concentrations as low as 10 microg/ml, which could account for some of the anti-inflammatory properties that have been described.     

鲨鱼肝超氧化物歧化酶的纯化与部分性质研究

 目的:从鲨鱼肝中分离提纯超氧化物歧化酶(SOD),并对其部分性质进行研究。方法:采用72℃热处理,硫酸铵分级分离和Sephadex G-100柱层析工艺。结果:鲨鱼肝SOD的亚基分子量为16.0kD;比活为5544U·mg^-1pr;提纯倍数为191.2;最大紫外吸收波长为258nm;凝胶电泳呈2带;对热稳定;KCN和H₂O₂均可抑制该酶的活性,而有机溶剂对酶活性无明显影响。结论:根据聚丙烯酰胺凝胶电泳、比活、相对分子量及紫外吸收光谱等性质的测定,证实从鲨鱼肝中提纯的SOD是均一的。     

Structure-activity relationship for antiinflammatory effect of luteolin and its derived glycosides

Luteolin and its derived glycosides such as a cynaroside, cesioside, isoorientin and stereolensin have been isolated and identified from different kinds of plant species. A (13)C NMR spectroscopic analysis of stereolensin has been done for the first time.These structurally related flavonoids were examined in vitro for their abilities to inhibit enzymes for the synthesis of thromboxane B(2) and leukotriene B(4) as well as hydrogen peroxide scavenging activity. Luteolin exhibited a high inhibitory activity against both thromboxane and leukotriene synthesis. In particular, a remarkable inhibitory effect was observed against leukotriene enzyme activity. The glycosides, cynaroside and cesioside, possessed a moderate inhibition activity against both enzyme synthesis pathways, while isoorientin and stereolensin exhibited selectively good activity against thromboxane synthesis.All the flavonoids showed excellent scavenging activity for the hydrogen peroxide at all the concentrations tested.The results demonstrated that the reactivities of luteolin and its related glycosides against arachidonic acid synthesis and hydrogen peroxide scavenging are dependent on their molecular structures. The presence of ortho-dihydroxy groups at the B ring and OH substitution pattern at C-5 position of the A ring could significantly contribute to the antiinflammatory and antioxidant activities of flavonoids.     

In vitro evaluation of effects of two Ghanaian plants relevant to wound healing

Commelina diffusa and Spathodea campanulata are used as wound-healing agents in Ashanti traditional medicine in Ghana. The methanol extracts of Commelina diffusa herb and Spathodea campanulata bark showed some level of antimicrobial activity with C. diffusa exhibiting selective antifungal activity against Trichophyton species. The extracts reduced the peroxidation of bovine brain extract with an IC(50) value of 1.39 mg/mL and 0.24 mg/mL, respectively. In addition the extracts also exhibited significant antioxidant activity by protecting MRC-5 cells from hydrogen peroxide induced oxidant injury at concentrations between 1 microg/mL and 10 microg/mL. The extracts showed no inhibition of NF-kappaB at 100 microg/mL. The antioxidant activities and antimicrobial activities suggest that the use of the plants in wound healing may be based on antioxidant and antiseptic effects of its constituents.