红曲色素β-环糊精包合物稳定性的初步研究

紫红曲霉经液体发酵可获得红曲色素 ,通过离心、过滤、乙醇浸提获得的发酵液中色素浓度为 0 .0 1 7g/mL。但其对光照、pH值、温度等不稳定限制了其用途。将 β 环糊精与所得色素包合 ,通过紫外扫描来初步表征包合物 ;并将包合物与游离色素放置在不同光照、pH值、温度条件下来比较各自的色泽保存率 ;结果表明 ,包合物与红曲色素相比 ,稳定性有一定程度的增强。     

鸡冠花红色素理化性质及其稳定性研究

目的：应用植物化学原理,对鸡冠花(Celosia cristata L．)红色素的理化性质及稳定性进行研究。方法：利用紫外-可见光吸收光谱、金属离子定性反应对色素作初步鉴定;观察光、热、pH值、还原剂、氧化剂、蔗糖、防腐剂、金属离子对色素稳定性的影响。结果：该色素易溶于水,在pH5以下,呈红色,初步定为花色苷类。其耐热性较差,耐可见光和紫外光性好;蔗糖和苯甲酸钠对色素稳定性无影响;H2O2对色素有不良影响;Na2SO3对色素的影响不显著;Zn^2 、Mg^2 、Ca^2 和Na^ 对色素稳定性无影响,而Fe^2 、Fe^3 、Cu^2 、Al^3 、Pb^2 、Sn^2 对色素有不良影响。结论：该色素属花色苷类,具水溶性,在一定条件下,稳定性好,是理想的植物色素。     

粒毛盘菌黄色素的稳定性研究

【目的】评价粒毛盘菌黄色素的稳定性。【方法】以色素吸光值为指标,研究温度、光照、pH、金属离子、氧化剂、还原剂及食品添加剂对黄色素稳定性的影响。【结果】该黄色素属黄酮类物质,易溶于水,在水溶液中紫外区及可见光区各呈现一个吸收峰,最大吸收波长分别为300 nm和410 nm;热稳定性较好,70°C处理4 h的色素保存率近90%;光照能降低黄色素水溶液的稳定性;随着pH的升高,色素溶液颜色逐渐加深,其A410增大;色素溶液在pH 9.0-10.0下较稳定,pH 10.0的色素溶液放置5 d后色素保存率近90%;Na_2SO_3对色素水溶液有增色作用,色素水溶液抗NaNO_2、H_2O_2能力较强,对抗坏血酸敏感。Fe~(3+)、Fe~(2+)与色素反应而改变色素颜色,Al~(3+)、Cu~(2+)、Zn~(2+)对色素水溶液具有一定的褪色作用,Ca~(2+)、K~+、Mg~(2+)对色素溶液无明显影响。蔗糖、葡萄糖和山梨酸钾对色素水溶液无明显影响,氯化钠对色素水溶液具有较弱的褪色作用。【结论】粒毛盘菌黄色素在稳定性上呈现出一定优势,具有开发潜力。     

三种天然果蔬色素稳定性研究

以新鲜菠菜、橘皮、番茄为原料,采用溶剂萃取法提取叶绿素、橘黄素、番茄红素,以吸光度为判断指标,研究了温度、光照、pH及金属离子对3种天然色素稳定性的影响。结果表明：橘皮色素稳定性较好,较耐热和耐光,pH稳定性较好;叶绿素耐热性和耐光性较差,酸性条件下较稳定;番茄红素稳定性最差,有一定的耐热性,不耐光,光照和紫外光下都易分解,不耐酸碱,酸性条件更不稳定。3种色素抗Mg2+、Na+、Ca2+等3种金属离子干扰能力较强,Cu2+、Fe3+对3种色素稳定性影响较大。     

离体培养藏红花细胞合成的藏红花色素稳定性

研究pH、温度、光照、氧化剂、还原剂、食品添加剂和金属离子对离体培养的藏红花细胞合成的藏红花色素稳定性的影响,并与藏红花柱头色素进行比较。结果表明:藏红花细胞合成的色素与柱头色素均为水溶性色素,呈亮黄色,对食品添加剂(食盐、柠檬酸、蔗糖、苯甲酸钠)和H2O2表现出良好的稳定性。与柱头色素相比,藏红花细胞合成的色素对强酸(pH1)、高温(80、100℃)和光照(日光灯光、紫外光)表现出更好的稳定性,对VC和Cu2+(0.001mol/L)的稳定性略差。稀碱溶液(0.47mol/LNa2CO3、0.1mol/LNaOH)、Na2SO3、Fe2+(0.050mol/L)和Fe3+能使细胞合成的色素色强增强。     

食品上的应用

951 479亮氯酸对水溶性红曲色素生产的干扰[英]/Lin,T.F.…矿Arch.,Microbi01.一1994,162(1～2).一114～119[译自DBA,1994,13(20),94一11743] 研究了氨基酸对红曲菌形成色素的酶的含量、作用及稳定性的影响。将10%体积的红曲埘Dnas—c"s sp.TTWM]36093种菌接种到发酵培养基上(每1蒸馏水含:50g麦芽糖、12.6g谷氨酸一钠、2.4gK 2HPO.、2.4 g KH 2 P0.、1g MgSC).·7H20、O.5g KCl、 .10rag ZnSO‘·7H20、10rag FeS()‘·7H 20和3mg 。MnS0‘·H 20、pH5.5)。培养36小时后过滤发酵液,培养剩余细胞.后期测定色素生产量。亮氨酸…     

蜀葵天然色素及其稳定性研究

以新疆地产蜀葵（Althaea rosea L.Cavan.）花为实验材料,用50%乙醇 0.5%盐酸为浸提剂,物料配比为1：10,提取出蜀葵花紫红色素,并从光、温度、pH值,氧化剂,还原剂,蔗糖,苯甲酸钠和不同金属离子对色素稳定性的影响进行了初步研究,结果表明：该色素在pH2时耐光性较好,温度在65℃以下和pH值4以下时色素稳定性较好,色素耐氧化性和耐还原性较差;蔗糖和苯甲酸钠对色素稳定性无不良影响,金属离子Cu^2 ,Fe^3 ,Sn^2 和Pb^2 对该色素稳定性有不良影响,Zn^2 对色素的稳定性只有轻微影响,而Al^3 ,Na^ ,Mg^2 ,K^ ,Fe^2 和Ca^2 对色素的稳定性则皆无不良影响。     

玫瑰色微球菌A-04的红色素鉴定及稳定性分析

从石油污染的土壤和水样中筛选出一株玫瑰色微球菌A-04 Micrococcus roseus,对其所产红色色素进行了分离,并初步鉴定了色素种类,基于对影响A-04色素稳定性的单因素分析基础之上,采用3因素3水平响应面分析法,进一步对影响色素稳定性的主要因素进行了优化分析。结果表明A-04所产红色色素为类胡萝卜素,对该菌株的色素稳定性的单因素条件分析,色素对环境条件的耐受性较好,在80℃、pH5. 0～8. 0等条件下依然能长时间保持鲜红而不褪色。经响应面优化分析表明:温度、pH和溶剂是影响该色素稳定性的主要因素,温度与溶剂的交互作用对色素稳定性的影响也较为明显。pH5. 0～8. 0之间时,在80℃范围内,温度越低,同时溶剂的极性越大,越有利于维持色素的稳定性。本研究结果为该色素的实际开发和应用奠定了基础。     

五味子色素提取及稳定性研究

目的：研究五味子色素的提取工艺条件及色素稳定性。方法：在单因素实验基础上利用L9（3^4）正交试验确定最佳提取工艺;以吸光度值的变化为指标,研究色素稳定性。结果：最佳提取工艺为∶料液比1∶25,乙醇浓度45%,浸提温度70℃,浸提时间40min;五味子色素光稳定性较好;在酸性、弱碱性条件下稳定,当pH≥12时出现颜色变化;对糖、氯化钠有一定稳定性;抗坏血酸和Na2SO3对色素影响较小;苯甲酸钠和H2O2对色素影响显著;金属离子Ca2＋、Mg2＋、Na＋对色素无明显影响,Fe2＋、Cu2＋、Al3＋对色素影响显著。     

黑莓果实色素的稳定性分析

研究了光照、温度、pH值、氧化剂（H2O2）和还原剂（Na2SO3）对黑莓（Rubus spp．）果实色素水溶液稳定性的影响。结果表明,黑莓果实色素为水溶性花色苷类化合物,对光和热有较好的耐受性,对pH、H2O2和Na2SO3较敏感,且耐还原性略强于耐氧化性。在小于pH4．0、温度低于50℃及避光条件下黑莓果实色素的稳定性较好,可作为食品色素添加剂使用。     

红龙草红色素稳定性的研究

分析了pH值、温度、光、过氰化氢、亚硫酸钠、Vc、葡萄糖、蔗糖和苯甲酸钠等对红龙草（Altemanthera dentate ‘Ruliginosa’）红色素稳定性的影响。结果表明,红龙草红色素对热的耐受性较强,但耐光照和耐氧化性较差,且还原剂亚硫酸钠对其也有微弱的影响;在不同的pH值条件下,其吸收峰没有改变,最大吸收波长为530nm;Vc和蔗糖对该色素没有破坏作用,并有一定的护色效果;葡萄糖和苯甲酸钠对该色素也无明显影响。     

Structural investigations on betacyanin pigments by LC NMR and 2D NMR spectroscopy

Four betacyanin pigments were analysed by LC NMR and subjected to extensive NMR characterisation after isolation. Previously, low pH values were applied for NMR investigations of betalains resulting in rapid degradation of the purified substances thus preventing extensive NMR studies. Consequently, up to now only one single (13)C NMR spectrum of a betalain pigment, namely that of neobetanin (=14,15-dehydrobetanin), was available. Because of its sufficient stability under highly acidic conditions otherwise detrimental for betacyanins, this pigment remained an exemption. Since betalains are most stable in the pH range of 5-7, a new solvent system has been developed allowing improved data acquisition through improved pigment stability at near neutral pH. Thus, not only (1)H, but for the first time also partial (13)C data of betanin, isobetanin, phyllocactin and hylocerenin isolated from red-purple pitaya [Hylocereus polyrhizus (Weber) Britton & Rose, Cactaceae] could be indirectly obtained by gHSQC- and gHMQC-NMR experiments.     

Effects of pH and Light on the Storage Stability of the Purple Pigment,Hordeumin, from Uncooked Barley Bran Fermented Broth

The pigment retention rate of hordeumin was higher than that of two standard anthocyanidins, cyanidin and delphinidin, when hordeumin and anthocyanidins were dissolved in Walpole buffer (pH 1.0) and stored. Moreover, when pigment solutions were stored at 15°C under light irradiation, the pigment retention rate of the hordeumin solution became higher than those of standard anthocyanidins (2 to 10 times) as the storage period increased. Comparing various pH buffers (MacIlvaine buffer, pH 2.2 to 7.0), the pigment retention rate of hordeumin at pH 5.0 was highest. Furthermore, the half-life of hordeumin at pH 5.0 was increased from 9 days to 17.5 days when nitrogen gas was bubbled into the hordeumin solution. We considered that the storage stability of hordeumin is higher than standard anthocyanidins because hordeumin is a complex with anthocyanin, tannin, and protein.     

Effects of pH and light on the storage stability of the purple pigment, hordeumin, from uncooked barley bran fermented broth

The pigment retention rate of hordeumin was higher than that of two standard anthocyanidins, cyanidin and delphinidin, when hordeumin and anthocyanidins were dissolved in Walpole buffer (pH 1.0) and stored. Moreover, when pigment solutions were stored at 15 degrees C under light irradiation, the pigment retention rate of the hordeumin solution became higher than those of standard anthocyanidins (2 to 10 times) as the storage period increased. Comparing various pH buffers (MacIlvaine buffer, pH 2.2 to 7.0), the pigment retention rate of hordeumin at pH 5.0 was highest. Furthermore, the half-life of hordeumin at pH 5.0 was increased from 9 days to 17.5 days when nitrogen gas was bubbled into the hordeumin solution. We considered that the storage stability of hordeumin is higher than standard anthocyanidins because hordeumin is a complex with anthocyanin, tannin, and protein.     

2-[3-(2-Thioxopyrrolidin-3-ylidene)methyll-tryptophan,a novel yellow pigment in salted radish roots

The structure of the yellow pigment found in salted radish roots was studied. It was found that 1-(2-thioxopyrrolidin-3-yl)-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (TPCC) was unstable under neutral pH, and was easily converted into the yellow pigment. The yellow pigment was isolated and identified as 2-[3-(2-thioxopyrrolidin-3-ylidene)methyl]-tryptophan (TPMT) by IR, MS, 1H-, and 13C-NMR spectroscopy. In addition, we proved that this compound was the main yellow pigment in salted radish roots. This compound induced no mutagenicity in Salmonella typhimurium TA98 and TA100, either with or without prior activation.     

榕树叶红色素的提取及其稳定性研究

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,研究榕树叶红色素的提取条件和稳定性。以水作提取剂,在室温下浸提24h,用紫外分析法研究色素的稳定性。色素在330am有最大吸收峰,该色素水溶性较好,pH值对色素的稳定性影响较大,但热稳定性良好。苯甲酸钠、柠檬酸、醋酸、蔗糖及葡萄糖等食品添加剂对色素无明显影响,淀粉对其影响较大,耐光性较差。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。     

2-[3-(2-Thioxopyrrolidin-3-ylidene)methyl]-tryptophan,a Novel Yellow Pigment in Salted Radish Roots

The structure of the yellow pigment found in salted radish roots was studied. It was found that 1-(2-thioxopyrrolidin-3-yl)-1,2,3,4-tetrahydro-β-carboline-3- carboxylic acid (TPCC) was unstable under neutral pH, and was easily converted into the yellow pigment. The yellow pigment was isolated and identified as 2-[3-(2-thioxopyrrolidin-3-ylidene)methyl]-tryptophan (TPMT) by IR, MS, ¹H-, and ¹³C-NMR spectroscopy. In addition, we proved that this compound was the main yellow pigment in salted radish roots. This compound induced no mutagenicity in Salmonella typhimurium TA98 and TA100, either with or without prior activation.