Differences in the carotenoid content of ordinary citrus and lycopene-accumulating mutants

High-performance liquid chromatography, coupled with photodiode array detection, was used to analyze the carotenoid composition of peel and juice vesicle tissues of ordinary and lycopene-accumulating mutants (referred to as red mutants in this article) of orange, pummelo, and grapefruit. Thirty-six major carotenoids, including some cis-trans isomers, were separated on a C30 reversed phase column, and 23 of them were identified on the basis of retention times and spectral characteristics with authentic standards. Carotenoid profiles varied with tissue types, citrus species, and mutations. beta-Citraurin occurred in the peel of oranges but not in juice vesicles, whereas the reverse was found for violaxanthin, 9-cis-violaxanthin, and luteoxanthin. The diversity of carotenoids in peel and juice vesicle tissues and the fact that there was over 250 times higher content of total carotenoids in peels of Yuhuan pummelo than juice vesicles suggested that the biosynthesis of carotenoids in these two tissues was independent and exchange of carotenoids between the tissues was not likely. Lutein was observed in peels of pummelos and grapefruits and juice vesicles of ordinary pummelo but not in orange tissues. Accumulation of lycopene and beta-carotene was observed in red mutant citrus, except for the peel of Cara Cara red orange. Additionally, phytoene accumulated in all tissues except for the peel of Chuzhou Early Red pummelo. No obvious change in the total content of xanthophylls was observed in the Cara Cara red orange. Ordinary grapefruit (Marsh) tissues and pummelo (Yuhuan) juice vesicles were almost devoid of carotenoids, and in red mutants, the content of total carotenoids increased dramatically up to 790-fold. The different changes in carotenoid content and profiles in mutant(s) of different citrus species suggest that the underlying mechanisms for the mutations might be different.     

高接在不同基砧的锦橙上的华红脐橙的栽培表现及矿质营养含量年变化

田间调查了高接在两种不同基砧的锦橙上的华红脐橙的栽培表现及矿质营养含量年变化差异。结果表明,在栽培效应上,红桔基砧树体生长较旺,投产晚,果实小,果实含酸量较高、糖酸比较低,出汁率和Vc含量较高;枳基砧则相反。在矿质元素含量年变化上,不同基砧树的叶片矿质元素含量年变化趋势除Mn、Zn外,其它元素含量年变化趋势差异明显;不同基砧根系的各种矿质元素含量年变化趋势基本相似;在不同基砧树之间,除根系Mg、Fe含量外,叶片和根系的各种矿质元素含量在年周期内的差异明显。     

Liquid chromatographic determination of naringin and neohesperidin as a detector of grapefruit juice in orange juice

Naringin/neohesperidin ratios can be used to differentiate orange juice which may contain added grapefruit juice from orange juice which may include juices from other naringin-containing cultivars. The naringin/neohesperidin ratios in juice vary from 14 to 83 in grapefruit (C. grandis) and from 1.3 to 2.5 in sour orange (C. aurantium) cultivars; the ratio is always less than 1 for the K-Early tangelo. Concentrations of both naringin and neohesperidin can be determined in orange juice by using a single liquid chromatographic isocratic reverse-phase system with a C-18 column. The detection limit for both compounds is 1 ppm with a linear working range to 500 ppm. Concentration relative standard deviations range from 0.47 to 1.06% for naringin and from 0.4 to 1.27% for neohesperidin. Naringin and neohesperidin recoveries ranged from 93 to 102% at concentrations of 5 and 50 ppm. Naringin values from blind duplicate samples of orange/grapefruit juice blends could be duplicated to +/- 3%.     

Characterization of major anthocyanins and the color of red-fleshed Budd Blood orange (Citrus sinensis)

High-performance liquid chromatography (HPLC) with photodiode array detection was applied for the characterization of anthocyanins in red-fleshed Budd Blood (Citrus sinensis) orange. More than seven anthocyanin pigments were separated within 30 min by using a binary gradient (0.1% H(3)P0(4) in water and 0.1% H(3)PO(4) in acetonitrile) elution on a Prodigy ODS column. Separations by reversed-phase HPLC and semipreparative HPLC on a Prodigy 10-microm ODS Prep column, and acid and alkali hydrolyses were used for identification of anthocyanins. The primary anthocyanins in Budd Blood orange grown in Florida were cyanidin-3-(6"-malonylglucoside) (44.8%) followed by cyanidin-3-glucoside (33.6%). Two other minor pigments were also acylated with malonic acid. Malonated anthocyanins represented the major proportion (>51%) of anthocyanins in Budd Blood orange. Total anthocyanin contents and juice color parameters (CIE L,a,b) were compared with six other Florida-grown blood oranges.     

Effect of processing techniques at industrial scale on orange juice antioxidant and beneficial health compounds

Phenolic compounds, vitamin C (L-ascorbic acid and L-dehydroascorbic acid), and antioxidant capacity were evaluated in orange juices manufactured by different techniques. Five processes at industrial scale (squeezing, mild pasteurization, standard pasteurization, concentration, and freezing) used in commercial orange juice manufacturing were studied. In addition, domestic squeezing (a hand processing technique) was compared with commercial squeezing (an industrial FMC single-strength extraction) to evaluate their influences on health components of orange juice. Whole orange juice was divided into soluble and cloud fractions after centrifugation. Total and individual phenolics were analyzed in both fractions by HPLC. Commercial squeezing extracted 22% more phenolics than hand squeezing. The freezing process caused a dramatic decrease in phenolics, whereas the concentration process caused a mild precipitation of these compounds to the juice cloud. In pulp, pasteurization led to degradation of several phenolic compounds, that is, caffeic acid derivatives, vicenin 2 (apigenin 6,8-di-C-glucoside), and narirutin (5,7,4'-trihydroxyflavanone-7-rutinoside) with losses of 34.5, 30.7, and 28%, respectively. Regarding vitamin C, orange juice produced by commercial squeezing contained 25% more of this compound than domestic squeezing. Mild and standard pasteurization slightly increased the total vitamin C content as the contribution from the orange solids parts, whereas concentration and freezing did not show significant changes. The content of L-ascorbic acid provided 77-96% of the total antioxidant capacity of orange juice. Mild pasteurization, standard pasteurization, concentration, and freezing did not affect the total antioxidant capacity of juice, but they did, however, in pulp, where it was reduced by 47%.     

Identification of isolutein (lutein epoxide) as cis-antheraxanthin in orange juice

The carotenoid profile of orange juice is very complex, a common characteristic for citrus products in general. This fact, along with the inherent acidity of the product, which promotes the isomerization of some carotenoids, makes the correct identification of some of these pigments quite difficult. Thus, one of the carotenoids occurring in orange juice has been traditionally identified as isolutein, a term used to refer to lutein epoxide, although enough evidence to support that identification has not been given. In this study, the carotenoid previously identified as isolutein/lutein epoxide in orange juice has been isolated and identified as a 9 or 9'-cis isomer of antheraxanthin as a result of different tests. To support this identification, a mixture of geometrical isomers of lutein epoxide isolated from petals of dandelions was analyzed under the same conditions used for orange juice carotenoids to check that neither their retention times nor their spectroscopic features matched with those of the orange juice carotenoid now identified as a cis isomer of antheraxanthin.     

In vitro availability of flavonoids and other phenolics in orange juice

Hand-squeezed navel orange juice contains 839 mg/L phenolics, including flavanones, flavones, and hydroxycinnamic acid derivatives. The flavanones are the main phenolics in the soluble fraction (648.6 mg/L) and are also present in the cloud fraction (104.8 mg/L). During refrigerated storage of fresh juice (4 degrees C), 50% of the soluble flavanones precipitate and integrate into the cloud fraction. Commercial orange juices contain only 81-200 mg/L soluble flavanones (15-33%) and the content in the cloud is higher (206-644 mg/L) (62-85%), showing that during industrial processing and storage the soluble flavanones precipitate and are included in the cloud. An in vitro simulation of orange juice digestion shows that a serving of fresh orange juice (240 mL) provides 9.7 mg of soluble hesperidin (4'-methoxy-3',5,7-trihydroxyflavanone-7-rutinoside) and 4.7 mg of the C-glycosylflavone vicenin 2 (apigenin, 6,8-di-C-glucoside) for freshly squeezed orange juice, whereas pasteurized commercial juices provide 3.7 mg of soluble hesperidin and a higher amount of vicenin 2 (6.3 mg). This means that although orange juice is a very rich source of flavanones, only a limited quantity is soluble, and this might affect availability for absorption (11-36% of the soluble flavanones, depending on the juice). The flavanones precipitated in the cloud are not available for absorption and are partly transformed to the corresponding chalcones during the pancreatin-bile digestion.     

Carotenoids, color, and ascorbic acid content of a novel frozen-marketed orange juice

A recently developed food, the so-called ultrafrozen orange juice (UFOJ), has been characterized in terms of carotenoid pigments, ascorbic acid, and color. The juice, obtained from Valencia late oranges, is frozen immediately after the squeezing of the oranges, which makes it a product showing good organoleptic and nutritional quality. In relation to the carotenoid profile, it was observed that the 5,6-epoxy carotenoids violaxanthin and antheraxanthin (specifically (9Z)-violaxanthin and (9Z)- or (9'Z)-antheraxanthin), were by far the major pigments and that dihydroxycarotenoids predominate over monohydroxycarotenoids. As far as color was concerned, it was seen that there were little differences among the juices analyzed. The hue of the samples, ranging from 77.19 degrees to 80.15 degrees and from 79.99 degrees to 83.04 degrees depending on the kind of instrumental measurement, and their chroma (ranging from 63.06 to 72.25 and from 44.40 to 58.38) revealed readily that the juice surveyed exhibited a deep orangeish coloration, the color coordinate best correlated with the total carotenoid content being b*. The levels of ascorbic acid ranged from 332.64 to 441.44 mg/L, with an average content of 391.06 +/- 28.86 mg/L.     

纽荷尔脐橙对建阳橘柚上柑橘衰退病毒分离株构成的影响

建阳橘柚兼具橘和柚的优良性状,为了解其携带的柑橘衰退病毒(CTV)分离株的分子特征及其传播到江西赣州对赣南脐橙产业的影响,将建阳橘柚(Citrus paradisi×C.reticulata)CTV分离株JY-5嫁接接种到赣南脐橙纽荷尔(C.sinensis)品种上,比较接种前后病毒外壳蛋白(cp)基因的HinfⅠRFLP和SSCP变化情况,实验结果表明,建阳橘柚上CTV分离株RFLP组群由接种前的单一组群变为混合组群,SSCP谱带数增加,在建阳橘柚上受抑制的CTV分离株在纽荷尔脐橙上能得到较好地增殖;同时接种前后分离株cp,p23和k17基因片段序列同源性及聚类分析表明,在建阳橘柚上的CTV分离株JY-5与其嫁接接种在纽荷尔脐橙上的JY-5R分离株并未在系统进化树上聚类在一起,表明两者不具有紧密的亲缘关系,结合RFLP和SSCP分析结果推测,JY-5R可能是在建阳橘柚上受抑制的分离株在纽荷尔脐橙上恢复了增殖。研究结果提示,建阳橘柚上的CTV分离株一旦传到赣南脐橙上,对赣南脐橙产业会带来一定的威胁。     

基于CVOR与3S技术融合的赣南脐橙园系统质量评估

  目的  本研究旨在构建针对脐橙园的园地CVOR指数模型,对赣南脐橙园系统进行质量评估。  方法  在生态系统健康评价CVOR理论框架下,以赣南典型脐橙产区寻乌县境内的脐橙园为研究对象,从人工生态系统的组分出发,结合自然要素和人为活动等多源数据,借助GIS软件和遥感平台,研究寻乌脐橙园的质量格局及驱动力。  结果  寻乌脐橙园的基况分指数（C）和VOR分指数（VOR）在空间分布上存在较明显的区别。相关性检验结果显示,两个分指数间的相关系数为0.13。CVOR指数与两个分指数的相关系数分别为0.60和0.84,表明CVOR指数可以作为表征脐橙园的系统状况和基况水平的综合指数。寻乌全县脐橙园的CVOR指数介于0 ~ 0.85之间。高质量的脐橙园主要连片分布于吉谭镇西部、文峰乡东部、澄江镇中部和南桥镇中部,最优质的地块在吉谭镇的圳下村、古丰村和兰贝村。低质量脐橙园在各乡镇呈散乱分布,质量最差的地块处于丹溪乡的双村村。交通条件、地块集聚程度和产量是决定寻乌县脐橙园质量及空间分布的主控因子。  结论  寻乌县脐橙园的系统质量总体良好,但部分脐橙园仍有质量提升的空间。所构建的CVOR指数模型可用于表征脐橙园的系统质量,可为其他园地系统的质量评估提供思路。     

Inactivation of heat-resistant pectinmethylesterase from orange by manothermosonication

Pectinmethylesterase of navel oranges shows two fractions greatly differing in thermostability. The most thermostable fraction accounts for approximately 10% of total activity. The thermal inactivation of this fraction follows first-order kinetics both in 5 mM, pH 3.5, citrate buffer and in orange juice at the same pH, showing a z value of 5.1 degrees C and an activation energy (E(a)) of 435 kJ mol(-)(1) K(-)(1). The heat resistance of the enzyme is approximately 25-fold higher in the juice than in citrate buffer. When ascorbic acid, sucrose, glucose, and fructose are added to the citrate buffer at the concentrations found in orange juice, the heat resistance of the enzyme increases 3-fold. The addition of pectin at 0.01% concentration multiplies it by a factor of 50. Manothermosonication (MTS), the simultaneous application of heat and ultrasound under moderate pressure (200 kPa), at 72 degrees C, increases the inactivation rate 25 times in buffer and >400 times in orange juice. MTS inactivation shows a higher z value (35.7 degrees C) and lower E(a) (56.9 kJ mol(-)(1) K(-)(1)) than simple heating.     

Color characteristics of monascus pigments derived by fermentation with various amino acids

Various pigment colors were produced by Monascus fermentations with separate addition of 20 amino acids. The color characteristics and structures of the pigment derivatives were investigated. When each amino acid was added to the fermentation broth as a precursor, pigment extracts with different hue and chroma values were obtained depending on the content ratios of yellow, orange, and red colors in the fermentation broth. The yellow and orange pigments were identical regardless of amino acid addition. The red compounds varied on the basis of the type of amino acid added. LC-MS and (1)H and (13)C NMR structural analyses confirmed that the derivative pigments contained the moieties of the added amino acids. L, a, and b values of the CIELAB color system for the derivative pigments were measured. Values of hue and chroma were then calculated. The colors of the derivative pigments were in the range of orangish red to violet red. The hydrophilicities/hydrophobicities of the derivative pigments could be predicted from their log P values, which were estimated using computer programs.     

Optimizing sampling of tomato fruit for carotenoid content with application to assessing the impact of ripening disorders

Color defines one aspect of quality for tomato and tomato products. Carotenoid pigments are responsible for the red and orange colors of tomato fruit, and thus color is also of dietary interest. The aims of this study were (1) to determine the relative importance of field sampling and analytical replication when measuring lycopene and beta-carotene in tomato fruit and (2) to determine the effect of yellow shoulder disorder (YSD) on the content of lycopene and beta-carotene in tomato juice and tissue. Our results show that increasing biological replications is an efficient strategy for reducing the experimental error associated with measurements of lycopene and beta-carotene. Analytical replications did not contribute significantly to observed variation, and therefore experimental efficiency will be gained by reducing analytical replications while increasing field replication. We found that YSD significantly reduces lycopene in affected tissue and in juice made from affected fruit. In contrast, beta-carotene concentrations were only reduced in affected tissue but were not significantly reduced in juice. With increasing interest in biofortified crops, modulating the carotenoid profile in tomato by minimizing YSD symptoms represents a strategy for improving tomato fruit quality that is currently supported by grower contract structure and processor grades.     

Effects of pulsed electric fields on the quality of orange juice and comparison with heat pasteurization

Effects of pulsed electric fields (PEF) at 35 kV/cm for 59 micros on the quality of orange juice were investigated and compared with those of heat pasteurization at 94.6 degrees C for 30 s. The PEF treatment prevented the growth of microorganisms at 4, 22, and 37 degrees C for 112 days and inactivated 88% of pectin methyl esterase (PME) activity. The PEF-treated orange juice retained greater amounts of vitamin C and the five representative flavor compounds than the heat-pasteurized orange juice during storage at 4 degrees C (p < 0.05). The PEF-treated orange juice had lower browning index, higher whiteness (L), and higher hue angle (theta) values than the heat-pasteurized orange juice during storage at 4 degrees C (p < 0. 05). The PEF-treated orange juice had a smaller particle size than the heat-pasteurized orange juice (p < 0.05). degrees Brix and pH values were not significantly affected by processing methods (p > 0. 05).     

Seasonal changes of carotenoid pigments and color in Hamlin, Earlygold, and budd blood orange juices

The developmental patterns of carotenoids in Hamlin, Earlygold (an early-maturing selection), and Budd Blood sweet orange juices were studied during the September to mid-January period of the 1996-97 and 1997-98 seasons. The carotenoid concentration of Earlygold increased by as much as 4.9 times during the color development compared to 3.9 times in Hamlin and 4.5 times in Budd Blood juice in the same period. For the profiles of carotenoid pigment, dramatic changes occurred among the pigments that were present in high concentrations at the beginning of the season, with lutein and violaxanthin noted as the predominant pigments in Hamlin fruit. A marked increase in the percentage of beta-cryptoxanthin allowed it to become a major pigment in the late stage of maturation. The color development in the new cultivar Earlygold was especially notable, reaching the 36 color number, which is grade A, by late October to mid-November whereas Hamlin juice did not reach this grade A color number until January. Budd Blood juice was similar in carotenoid pigment content and seasonal changes to Hamlin juice, but also, the development of red anthocyanin pigment in January significantly increased juice color.     

基于近红外光谱的脐橙产地溯源研究

为研究近红外光谱分析技术鉴别脐橙产地的可行性,该文采用江西、重庆和湖南3个产地脐橙样品1140～1170nm波段的近红外光谱经一阶导数(9点平滑)预处理,分别建立了簇类独立软模式法脐橙产地鉴别模型。在5%显著水平下,模型对3个产地训练集样品的识别率均为100%,拒绝率分别为85.7%、83.3%、100%;对验证集样品的识别率均为100%,拒绝率分别为100%、89.5%、100%,表明簇类独立软模式法模型基本能够判别脐橙产地。将江西、重庆和湖南3个产地的脐橙样品分别赋值0、1、?1,在全波段范围内建立原始光谱脐橙产地的偏最小二乘判别模型,其预测值与真实值的决定系数为0.973,校正标准差为0.110,预测标准差为0.159,模型对训练集和验证集样品的识别率达到100%。因此,应用近红外光谱分析技术可准确、快速地追溯脐橙产地来源。     

超滤对血橙果汁中抗氧化成分及总抗氧化能力的影响

采用管式聚偏氟乙烯(PVDF)超滤膜，探讨了超滤对血橙果汁中抗氧化成分及总抗氧化能力的影响。结果表明，其对维生素C和花青素类成分的保存率约为85%左右，对几种酚酸和类黄酮组分（除槲皮素外）的保存率均在90%以上。同未杀菌的血橙原汁相比，巴氏杀菌汁的总抗氧化能力(TAA)损失率为23%，而超滤澄清汁仅为10%左右，主要与维生素C和花青素含量损失有关。     

Sensitive micellar electrokinetic chromatography-laser-induced fluorescence method to analyze chiral amino acids in orange juices

In this work a new method to detect the existence of chiral amino acids in orange juice is presented. The method employs beta-cyclodextrins and micellar electrokinetic chromatography with laser-induced fluorescence (MEKC-LIF) to separate and detect L- and D-amino acids (L-aa and D-aa) previously derivatized with fluorescein isothiocianate (FITC). A systematic optimization of the chiral-MEKC conditions is done bringing about in less than 20 min a good separation of the main amino acids found in orange juice (i.e., Pro, Asp, Ser, Asn, Glu, Ala, Arg, and the nonchiral GABA, i.e., gamma-aminobutyric acid). Using this procedure, the analysis time reproducibility for the 15 standard compounds (L-aa, D-aa, and GABA) has been determined to be better than 0.2% (n = 5) for the same day and better than 0.7% (n = 15) for three different days. Corrected peak area reproducibility is somewhat lower, providing values better than 3.3% (n = 5) for the same day and 6.9% (n = 15) for three different days. The limit of detection using this procedure was determined to be 0.86 attomoles for L-Arg. The optimized FITC derivatization method allows the easy and straightforward detection of amino acids in orange concentrates and juices (i.e., only centrifugation of diluted samples for 5 min is needed prior to their derivatization). D-Ala, D-Asp, D-Arg, and D-Glu were determined in orange juices and orange concentrates from different geographical origins using this new method. Moreover, the effect of different temperature treatments (50, 92, and 150 degrees C) on the content of D-aa in orange juice was evaluated.     

Gas chromatographic determination of fatty acids and sterols in orange juice

A gas chromatographic (GC) method has been developed for the simultaneous quantitation of fatty acids and sterols in orange juice, using a bonded phase fused silica capillary column of intermediate polarity, splitless automatic injection, and flame ionization detection. Sample preparation has been simplified by using 1 g C-18 adsorbent in a disposable minicolumn to extract 2 mL orange juice. Methylation of fatty acids and silylation of the sterols were carried out in the eluted extract (low polarity lipid fraction). The method precision was 7%; recoveries ranged from 83 to 113%. The precision of the injection technique was 2%. Seven major fatty acids and 5 sterols in orange juice were quantitated by the GC method and identified by GC/mass spectrometry. Quantitative data for several orange juice samples indicated that the levels of the compounds of interest were in the 1.3-72.0 mg/L range. The results demonstrate that bonded phase fused silica capillary GC has great versatility and potential for the quantitative determination of fatty acids and sterols.