Effect of ammonium nitrate on the production of PP-V and monascorubrin homologues by Penicillium sp. AZ

A fungal strain, Penicillium sp. AZ, has been found to produce the monascorubramine homologues, PP-V [(10Z)-3-(9a-methyl-3-octanoyl-2,9-dioxo-2,7,9,9a-tetrahydro-furo[3,2-g]isoquinolin-6-yl)-acrylic acid] and PP-R [(10Z)-7-(2-hydroxyethyl)-monascorubramine] when cultured in a medium composed of soluble starch, ammonium nitrate, yeast extract, and citrate buffer, pH 5.0. When ammonium nitrate was omitted from the culture medium, PP-V and PP-R production was replaced by orange (PP-O) and yellow-orange (PP-Y) pigment production. The structures of these pigments were determined by FAB-MS and 1H and 13C NMR to be novel compounds, (10Z)-3-(9a-methyl-3-octanoyl-2,9-dioxo-9,9a-dihydro-2H-furo[3,2-g]isochromen-6-yl)-acrylic acid and (10Z)-monascorubrin, respectively.     

Biosynthesis of PP-V, a monascorubramine homologue, by Penicillium sp. AZ

The biosynthetic pathway of PP-V, a new monascorubramine homologue, was elucidated by 13C-labeling studies. The [1-13C] of acetate was incorporated into 2-, 3a-, 4a-, 6-, 8-, 9-, 11-, 13-, 15-, 17-, and 19-Cs of PP-V, and the [2-13C], into 3-, 4-, 5-, 8a-, 9a-, 10-, 12-, 14-, 16-, 18-, and 20-Cs. These incorporation patterns coincide with those reported in the biosynthesis of a Monascus azaphilone pigment, monascorubrin.     

Biosynthesis of PP-V, a monascorubramine homologue, by Penicillium sp. AZ

The biosynthetic pathway of PP-V, a new monascorubramine homologue, was elucidated by ¹³C-labeling studies. The [1-¹³C] of acetate was incorporated into 2-, 3a-, 4a-, 6-, 8-, 9-, 11-, 13-, 15-, 17-, and 19-Cs of PP-V, and the [2-¹³C], into 3-, 4-, 5-, 8a-, 9a-, 10-, 12-, 14-, 16-, 18-, and 20-Cs. These incorporation patterns coincide with those reported in the biosynthesis of a Monascus azaphilone pigment, monascorubrin.     

PP-R, 7-(2-hydroxyethyl)-monascorubramine, a red pigment produced in the mycelia of Penicillium sp. AZ

A red pigment was extracted and purified from the mycelia of a newly isolated strain of Penicillium sp., Penicillium sp. AZ, which produced a soluble violet pigment PP-V, 12-carboxyl-monascorubramine, in the culture fluid. The red pigment, PP-R, was determined by FAB-MS and 1H and 13C NMR to be a novel compound, 7-(2-hydroxyethyl)-monascorubramine.     

板栗壳棕色素的抗氧化活性及其活性成分的分离、鉴定

板栗壳棕色素是一种重要的天然食用色素,本文研究了其光谱特性、抗氧化活性和化学成分组成,为板栗壳棕色素的深入应用提供依据。利用碱提酸沉等方法从板栗壳中提取出板栗壳棕色素,紫外和红外光谱法初步确定其光谱特性,并采用Folin-Ciocalteu法、苯酚-硫酸显色法和BCA法测定棕色素中总多酚、多糖和蛋白质的含量。以DPPH自由基清除法测定棕色素的抗氧化活性,采用色谱法分离纯化其中的化合物,并通过液相色谱、质谱与核磁对其进行鉴定。结果表明,板栗壳棕色素的水溶液在276 nm波长有最大吸收,红外光谱图显示出明显的多酚类物质特征。棕色素中总多酚、多糖和蛋白质含量分别为42.35%、13.75%和8.08%。棕色素对于DPPH自由基的IC₅₀为0.44 mg/mL,具有较强的抗氧化能力。从棕色素中分离得到10个多酚类化合物,分别为间苯二酚(1)、2-羟基-3',4'-二羟基苯乙酮(2)、邻苯二酚(3)、原儿茶醛(4)、没食子酸甲酯(5)、2,5-二羟基苯乙酮(6)、β-羟丙基香草酮(7)、原儿茶酸甲酯(8)、对香豆酸(9)和阿魏酸(10)。     

板栗皮棕色素的提取与稳定性研究

本文以鞍山岫岩地区所产的板栗皮为原料，对其棕色素进行了提取，同时对其物理、化学性质进行了研究。实验表明：它是一种水溶性色素。当色素溶液的pH值为3～9时，此色素稳定性较好；对氧化剂H2O2、还原剂Na2SO3的耐受能力强。在食品工业中有一定的开发利用价值。     

茅莓果红色素的提取及其稳定性分析

以茅莓果为原料提取茅莓果红色素,并对茅莓果红色素的稳定性进行研究。结果表明,色素最佳提取工艺为:提取剂1.5%盐酸乙醇(V/V),浸提温度为70℃,时间为6h,料液比为1∶700。稳定性研究表明,该色素对热和还原剂的稳定性较好。日光对色素的影响较大,所以在储存过程中应避免阳光直射。常用的食品添加剂如糖类,苯甲酸钠,柠檬酸,山梨酸钾,木糖醇,甜蜜素,糖精对色素的光泽无大的不良影响,其中抗坏血酸对色素的影响相对较大,因此其用量不宜过多;金属离子中Fe3+,Cu2+对色素影响较大,其他如Zn2+,K+,Ca2+,Mg2+,Na+,Al 3+对色素无不良影响。该色素耐酸碱性良好,在pH≤8时,显示稳定的红色;在pH>8时,显示稳定的淡黄色。     

Characterization of a new yellow pigment from model reaction system related to garlic greening

Three yellow pigments have been identified from three reaction systems containing pyruvic acid and 2-(1H-pyrrolyl) acetic acid, 1-(2′-methyl-1′-carboxy-propyl) pyrrole, and 1-(2′-methyl-1′-carboxy-butyl) pyrrole (a kind of precursor of garlic green pigment) related to garlic greening in previous paper, respectively. In the present study, another kind of yellow pigment from the same system containing pyruvic acid and 2-(1H-pyrrolyl) acetic acid was identified by liquid chromatography–electrospray ionization mass spectrometry (LC-ESI MS/MS) and high-resolution electrospray ionization mass spectrometry. This kind of pigment made predominant contribution to the production of yellow pigment in this model reaction pathway, which was involved in garlic discoloration. It was observed that there were two more methyl groups located on two conjugated double bonds that bridged two moles of 2-(1H-pyrrolyl) acetic acid compared to the structures of pigments, which was identified in our previous paper. Molecular weight of the pigment is 329.1495 [M+H]⁺, and its molecular formula is C₁₈H₂₀N₂O₄ which has a maximal absorbance at 436.9 nm, due to its conjugated structure.     

榴莲果皮黄色素的提取及其稳定性的研究

文章以榴莲果皮为原料提取榴莲皮黄色素,在单因素循环的基础上,进行L9(33)正交试验,最后测试了色素的稳定性。结果表明,色素提取的最佳工艺为:提取剂为乙酸乙酯、液料比1∶30、浸提温度50℃,提取时间4h。稳定性研究表明:(I)温度、氧化还原剂、金属离子及各类常用的食品添加剂的对该色素稳定性影响较小,其中柠檬酸有增色的作用,金属离子中Fe3+,Cu2+对色素影响较大,且有一定的减色作用;(II)日光对色素的影响较大,所以在储存过程中应避免阳光直射;(III)pH对色素有一定的影响,在pH接近12时,色素明显变色。     

FATTY ACID COMPOSITION IN TISSUES OF MICE FED DIETS CONTAINING CONJUGATED LINOLENIC ACID AND CONJUGATED LINOLEIC ACID

The influence of 1% alpha-eleostearic acid (α-ESA, cis9,trans11,trans 13-18:3) and 1% punicic acid (PA, cis9,trans11,cis13-18:3) on fatty acid composition in mouse tissues was compared with conjugated linoleic acid (CLA, mixture of primarily cis9,trans11- and trans10,cis12-18:2) in the present study. The content (% total fatty acids) of 18:2n-6 was significantly reduced in the heart and adipose tissues, and total polyunsaturated fatty acids (PUFAs) and n-6 PUFA were significantly reduced in adipose tissue by α-ESA, PA and CLA feeding. The content of 22:6n-3 and total n-3 PUFA were significantly increased in the liver, kidney and heart by PA feeding, but not by α-ESA. In contrast to PA, supplementation with CLA significantly decreased 22:6n-3 in the liver, kidney and heart. The content of 20:4n-6 was significantly decreased in the liver and kidney by CLA feeding, but not by α-ESA and PA. The present results indicate that α-ESA, PA and CLA have differential effects on 22:6n-3 and 20:4n-6 content in mouse tissues.

PRACTICAL APPLICATIONS

Conjugated linolenic acid (CLnA), a group of octadecatrienoic acid isomers with a conjugated triene system, has been reported to exhibit favorable physiological effects, including anticancer properties and regulation of lipid metabolism. Punicic acid and alpha-eleostearic acid, two isomers of CLnA, have been shown to convert into cis 9, trans 11-18:2 in vivo . The effect of CLnA on fatty acid composition in mouse tissues was investigated in comparison with CLA mixtures in the present study. The data obtained here could provide information for the potential application of CLnA-containing seeds as functional food ingredients, a natural source of endogenously formed cis 9, trans 11-18:2 and a dietary feeding strategy to beneficially modify the fatty acid composition of animal tissues.     

R362菌株产黑色素提取及稳定性研究

通过液体培养R362菌株,提取其产生的黑色素,并研究酸度、温度、光照、碳水化合物、氧化剂、还原剂、金属离子对色素稳定性的影响。结果表明:该色素的最大吸收峰为390nm,在碱性条件下较稳定,在酸性条件下易褪色;热、光、碳水化合物对色素稳定性无影响,色素对H2O2和Na2SO3较敏感;几种常见的金属离子(除Fe3 )对色素色泽无影响。     

阿魏酸的功能和应用

阿魏酸是植物界普遍存在的一种酚酸 ,在植物体内很少以游离态存在 ,主要与低聚糖、多胺、脂类和多糖形成结合态。它有许多保健功能 ,如清除自由基、抗血栓、抗菌消炎、抑制肿瘤、防治高血压、心脏病、增强精子活力等。阿魏酸毒性低 ,易于为人体代谢 ,其用途越来越广泛。阿魏酸在食品工业中主要用于制备天然香兰素、抗氧化剂、防腐剂、交联剂和机能促进剂等 ,阿魏酸可通过化学合成法和提取法获得     

Antibodies to the quinolones and fluoroquinolones for the development of generic and specific immunoassays for detection of these residues in animal products

Several quinolone and fluoroquinolone haptens have been used to raise polyclonal antibodies exhibiting both specific and generic properties for these classes of antimicrobial compounds. The antisera have been assessed in rapid enzyme immunoassays (ELISAs) designed to exploit the specificities obtained. A direct generic ELISA for both the quinolones and fluoroquinolones has been developed that uses the cross-reactivity of an antibody raised against norfloxacin (1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid) linked to ovalbumin via a secondary amine group on the piperazinyl moiety to detect nine different drugs in these classes. Specific ELISAs to ciprofloxacin (1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid), enrofloxacin (1-cyclopropyl-7-(4-ethyl-1-piperazinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid), flumequin (9-fluoro-6,7-dihydro-5-methyl-1-oxo-1H,5H-benzo(ij)quinolizine-2-carboxylic acid) and nalidixic acid (1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-carboxylic acid) have also been developed with a high degree of specificity to the individual compounds. The assays measure drug residues in bovine milk and ovine kidney with an interassay relative standard deviation (s r ) of 10.5% or less and intra-assay s r of 11.2% or less. Sensitivity is less than 4 μg kg -1 for both the generic and specific assays for all but one of the compounds tested. (Pipemidic acid (8-ethyl-5,8-dihydro-5-oxo-2-(1-piperazinyl)pyrido(2,3-d)pyrimidine-6-carboxylic acid) is detectable at 6 μg kg -1 in kidney.)     

烤烟新品种中烟特香301特征香气物质研究

为从分子水平认识烤烟新品种中烟特香301特征香韵的香气物质基础,采用顶空-箭型固相微萃取-气相色谱质谱联用法（HS-SPME Arrow-GC/MS）测定了中烟特香301和对照品种中烟100中挥发、半挥发性香气成分,结合主成分分析（PCA）和偏最小二乘-判别分析（PLS-DA）方法分析了中烟特香301的特征香气成分。结果表明：(1)两个品种中共检测到香气物质102种,其中质体色素降解产物20种、美拉德反应产物32种、苯丙氨酸和木质素转化产物12种、西柏烷类降解转化产物2种、脂类代谢转化产物2种、氨基酸降解产物5种、其他来源降解产物29种;(2)中烟特香301与中烟100含量差异显著的香气物质有46种,包括质体色素降解产物9种、美拉德反应产物15种、苯丙氨酸和木质素转化产物4种、脂类代谢转化产物2种、氨基酸降解产物2种、其他类14种,其中41种香气物质含量增加。中烟特香301的特征香韵可能与其香气物质的大幅增加密切相关,质体色素降解产物尤其是类胡萝卜素降解产物对中烟特香301花香香韵的形成发挥主要作用。     

含硫吡咯基氨基酸化合物的合成表征及其与丙酮酸的反应

通过Paar-Knnor有机合成方法得到一种新的含硫吡咯基氨基酸化合物.此物质的结构类似于可能的大蒜绿变色素前体2-(3,4-dimethyl-1H-pyrrolyl)-3-methylbutanioc acid.(3,4-二甲基-1H-吡咯基)-3-甲基丁酸,简称为含硫吡咯基氨基酸,此物质与丙酮酸反应不能产生黄色素.丙酮酸是大蒜绿变过程中丙烯基半胱氨酸亚砜在蒜酶作用下的产物,先前合成的色素前体类似物与丙酮酸反应大多可以产生黄色素.研究表明,该中间体通过此途径与黄色素的产生无关.     

紫红薯及玫瑰花色素稳定性的研究

紫红薯是近年来我国兴起的红薯新品种,含有丰富的花青素,该类色素在加工过程中稳定性很差.本文主要以宁紫4号为原材料,在相同的条件下与天然花卉的花青素比较它们的稳定性,为食品加工提供一定的参考依据.结果表明:紫红薯色素热稳定性较好,耐酸,常见金属离子中Fe~(3+)和Fe~(2+)引起紫红薯色素的损失较大.而玫瑰花色素在弱酸下较稳定,常见金属离子中Fe~(3+)和Fe~(2+)对玫瑰花色素影响较大,Al~(3+)、Cu~(2+)、Zn~(2+)对玫瑰花色素影响相对较小.两种物质的色素对碱都很敏感,碱使色泽加深.     

Green pigmentation characteristics of amino compounds with thiosulfinates obtained from garlic (Allium sativum L.)

Pigmentation of various amino compounds with garlic thiosulfinates was investigated. Aminocarbonyl compounds including aldehydes, amino acids, peptides, and proteins formed compound-specific characteristic pigments with thiosulfinates, regardless of their origin. An intact amino group was essential, and the replacement of an amino group’s hydrogen atom made them unable to form pigment. Water-soluble proteins exhibited relatively intense green pigmentation, whereas water-insoluble ones showed negligible pigmentation. Taurine, a natural amino compound, which has a sulfonate group in place of the carboxyl group of an amino acid, also participated in pigment formation with thiosulfinates. Other sulfonates with an amino group, including aminosulfonic acid and ptoluenesulfonamide, did not form pigment. This is the first time that the pigmentation of proteins, amino aldehydes, ammonia and taurine with thiosulfinates has been reported.     

辣椒红色素的稳定性及在食品中的应用研究

研究了辣椒红色素的稳定性以及在食品中的应用.研究发现,辣椒红色素对热稳定;辣椒红色素在pH=2-12之间色素稳定;在暗室和室内光线下,色素无褪色现象,在日光下不到半天的时间色素几乎损失殆尽,紫外光对色素有明显的影响;Cu2 与色素发生反应,色泽改变,其它金属离子(Sn2 、Al3 )浓度大于300mg.ml-1对色素有一定影响;辣椒红色素对还原剂和防腐剂稳定,对氧化剂不稳定.本文还研究了辣椒红色素在食品中的着色及稳定性.     

乌洋芋色素的理化性质研究

乌洋芋作为马铃薯的特异变种,其色素理化性质研究表明,乌洋芋色素是花青素类色素,水溶性好,颜色随pH值变化而变化,pH值小于3时比较稳定,最大吸收波长为528nm;在酸性条件下对光、氧化剂及高浓度还原剂敏感,但对热及Cu2 、Fe2 、Fe3 、Al3 、Mg2 、Ca2 等金属离子有较好的稳定性,且Cu2 、Fe2 对其有增色作用。     

金盏菊花中色素的提取工艺及稳定性研究

目的：确定金盏菊花色素的最佳提取工艺,并对其稳定性进行研究。方法：以浸提法对金盏菊花中的色素进行提取,通过对提取剂、料液比、提取温度、提取时间4因素进行,L9(34)正交试验得到最佳提取条件;同时考察光照、热和食品添加剂等对色素稳定性的影响。结果：金盏菊花色素最佳提取工艺为提取剂90%乙醇、料液比1:8(g/mL)、在70℃水浴中浸提40min;该色素在酸性条件下稳定性较好,对光和热稳定性好;pH值对色素的稳定性影响较大,在酸性条件(pH5)下该色素较稳定;常用食品添加剂如葡萄糖、蔗糖对色素的色泽无不良影响,金属离子Na+、Mg2+、Ca2+、Cu2+对金盏菊花色素无不良影响,而Fe3+则对色素有明显影响。结论：获得金盏菊花中色素提取的最佳工艺;色素对光、热、常用食品添加剂的稳定性良好,为其在食品和药品中的应用提供了广阔的前景。