不同晚熟柑橘中酚类物质的含量检测及分析

采用超高效液相色谱(ultra-performance liquid chromatography,UPLC)对9种晚熟柑橘(沃柑、春见、大雅柑、不知火、默科特、红肉脐橙、伦晚脐橙、红翠2号和塔罗科血橙)中的主要酚类物质(13种类黄酮和7种酚酸)进行测定,分析比较不同品种柑橘果皮、果肉和果汁(柑橘原汁)中酚类物质种类和含量的差异。结果表明:9个柑橘品种的果皮、果肉、果汁中,类黄酮均以橙皮苷为主,酚酸以阿魏酸为主,且果皮中多甲氧基黄酮含量丰富。在9个柑橘品种果汁中,春见的橙皮苷、咖啡酸含量最高。果肉中,沃柑中阿魏酸、咖啡酸、芥子酸含量最高,塔罗科血橙的橙皮苷、对香豆酸含量最高。果皮中,默科特的芸香柚皮苷、川皮苷、阿魏酸含量最高。杂柑果皮中咖啡酸、阿魏酸及川皮苷含量高于橙类。晚熟柑橘含有丰富的酚类物质,并呈现显著的多样性。     

不同成熟期蜜桔中酚酸的组成与分布

酚酸具有多种生理功能,在植物中广泛存在.柑橘可能是膳食酚酸的重要来源.采用HPLC-PDA测定了不同成熟期温州蜜桔中八种酚酸的含量,即绿原酸、咖啡酸、对香豆酸、阿魏酸、芥子酸、原儿茶酸、对羟基苯甲酸和香草酸.结果显示,果肉中酚酸含量随成熟度提高而减少,果皮酚酸含量在半成熟期最高;果皮中酚酸含量大大高于果肉;果皮果肉中都以肉桂酸型酚酸为主,苯甲酸型酚酸含量较少;蜜桔果实中绿原酸和阿魏酸是所测八种酚酸中含量最高的.对柑橘中酚酸组成与分布的研究可望应用于食品营养标识、柑橘品种的识别或加工果汗掺假的识别等.     

红肉与白肉火龙果酚酸组成及其抗氧化活性

为研究火龙果果皮、果肉中的酚酸组成及抗氧化活性,以红肉火龙果和白肉火龙果为研究对象,采用高效液相色谱法(HPLC)测定其游离型酚酸(FPA)、可溶共价结合型酚酸(HPA)和束缚型酚酸(BPA)组分与含量,并测定其体外抗氧化活性,包括DPPH清除能力、还原能力和羟自由基抑制能力。结果表明:两种火龙果中酚酸含量顺序为:红肉果肉 > 白肉果肉 > 白肉果皮 > 红肉果皮。火龙果果肉中酚酸主要以HPA形式存在,果皮中酚酸的主要存在形式为BPA。没食子酸是红肉火龙果中的主要酚酸(1700.70 μg/g干重);原儿茶酸是白肉火龙果中主要酚酸(1877.50 μg/g干重)。红肉果皮的BPA对DPPH自由基清除能力最强(2206.37 mg/L),红肉果肉的HPA还原能力最强(A₇₀₀=0.82),白肉果皮的HPA对羟自由基抑制能力最强(77.50 U/mL)。酚酸含量与抗氧化活性的相关性分析表明:DPPH自由基清除能力和还原能力与酚酸的含量呈极显著(P<0.01)正相关,羟自由基抑制能力与酚酸含量无显著相关性。     

柑橘果肉、果皮中酚类物质含量差异性研究

采用高效液相色谱法(high performance liquid chromatographic,HPLC)对8种橙类和杂柑中10种酚类物质含量进行测定,探讨不同柑橘品种果肉和果皮中酚类物质种类和含量的差异,分析其规律。结果表明,10种物质能在55 min内分离,线性范围为0.25~200 mg/L,相关系数达0.999 1~1,精密度(RSD≤1.90%)、重复性(RSD≤3.52%)和稳定性(RSD≤4.22%)较好,平均回收率为90.26%~118.85%(RSD为0.96%~3.01%),表明方法的准确度较高。在橙类和杂柑中,橙类果皮中芥子酸含量显著高于杂柑,杂柑果皮中芦丁含量显著高于橙类;果肉中酚类物质含量低于果皮;果实中酚酸以咖啡酸和绿原酸为主,类黄酮以芦丁和柚皮苷为主;在8个柑橘品种果肉中,金诺的阿魏酸、没食子酸和芦丁含量最高。在8个柑橘品种果皮中,口之津32号的咖啡酸、阿魏酸、对羟基苯甲酸含量最高,沃柑的新橙皮苷、柚皮苷、没食子酸和绿原酸含量最高。     

椪柑、温州蜜桔果皮中酚类物质组成及抗氧化能力研究

目的:研究椪柑、温州蜜桔果皮中酚酸与黄烷酮糖苷组成及其抗氧化能力。方法:高效液相法测定椪柑、温州蜜桔果皮中九种酚酸和两种黄烷酮糖苷的组成与含量。用福林酚法、ABTS法和FRAP法对椪柑、温州蜜桔果皮甲醇提取液抗氧化能力进行评价。结果:柑橘果皮中可溶酯化酚酸部分所占比例最大,肉桂酸型酚酸是柑橘皮中的主要酚酸,且主要以酯化形式存在,其含量排列顺序一般为:阿魏酸>对香豆酸>芥子酸>咖啡酸。温州蜜桔果皮中有较高总酚酸含量(p<0.05)。椪柑果皮主要含橙皮苷,温州蜜桔果皮含橙皮苷和少量柚皮芸香苷。温州蜜桔果皮中总黄烷酮糖苷含量高于椪柑(p<0.05)。总的来说椪柑果皮提取液抗氧化活性略高于温州蜜桔。结论:HPLC测定柑橘皮中酚酸与黄烷酮糖苷可取得良好结果,抗氧化实验表明柑橘皮具有一定的抗氧化能力。     

7种柑橘多酚、黄酮含量及其抗氧化活性比较研究

比较研究7种不同柑橘果皮和果肉多酚、黄酮含量及其抗氧化能力。结果表明,7种不同柑橘果及果皮的多酚、黄酮含量存在显著性差异。其中柑橘果皮的多酚含量为24.77 mg GAE/g～47.48 mg GAE/g,黄酮含量介于10.47 mg CE/g～22.11 mg CE/g之间,其中以塔罗科血橙皮中的多酚、黄酮含量最多。柑橘果肉的多酚含量在0.43 mg GAE/g～0.75 mg GAE/g之间;黄酮含量在0.29 mg CE/g～0.63 mg CE/g之间,其中分别以锦红冰糖橙和锦蜜冰糖橙果肉中的多酚、黄酮含量最多。7种柑橘果皮中,DPPH·、铁还原抗氧化能力(ferric reducing antioxidant power,FRAP)、ABTS+·3种抗氧化活性分别介于2.41μmol TE/g～7.90μmol TE/g、15.38μmol TE/g～54.76μmol TE/g、28.11μmol TE/g～46.46μmol TE/g,柑橘果肉的3种抗氧化活性分别介于6.95μmol TE/g～20.21μmol TE/g、2.40μmol TE/g～8.10μmol TE/g、8.55μmol TE/g～20.90μmol TE/g,研究发现,塔罗科血橙果皮和果肉的抗氧化能力最强。通过主成分分析和聚类分析,可将7种柑橘分成四类。     

9个柑橘品种不同组织中5-甲基四氢叶酸含量的比较

以9个不同种和品种柑橘为试验原料,采用反相高效液相荧光检测法(RP-HPLC-FLD)测定不同柑橘品种中各组织5-甲基四氢叶酸的含量。结果表明:甜橙类果实果肉中含5-甲基四氢叶酸最高,尤以哈姆林甜橙最高,为29.28μg/100 g;其次为柚类,沙田柚果肉中5-甲基四氢叶酸的含量为23.45μg/100 g,梁平柚15.01μg/100 g;柑类品种果实果肉5-甲基四氢叶酸的含量较低,早津温州蜜柑果肉中的5-甲基四氢叶酸含量为15.58μg/100 g,台湾椪柑8.92μg/100 g;柠檬中的含量最低,只有4.1μg/100 g。大多数品种中,不同组织5-甲基四氢叶酸含量的基本排序为种子>果肉>囊衣>果皮。从整体上看,甜橙类果实中5-甲基四氢叶酸的含量最高。     

高效液相色谱-质谱检测赣南脐橙幼果中酚酸

通过优化色谱分离条件和质谱条件,建立了基于高效液相色谱-串联质谱测定赣南脐橙幼果中酚酸的测定方法。以咖啡酸、对香豆酸、阿魏酸、芥子酸、没食子酸和对羟基苯甲酸6种酚酸化合物标准品,对赣南脐橙幼果6种酚酸进行定量分析。色谱柱为Agilent-C_(18) column(2.1mm×100 mm,1.8μm),流动相为0.1%甲酸水溶液(A)/乙腈(B)进行梯度洗脱,柱温35℃,流速0.3 m L/min;质谱以负离子模式进行多反应监测模式(MRM)扫描。结果表明:利用该方法可同时对赣南脐橙幼果中的咖啡酸、对香豆酸、阿魏酸、芥子酸、没食子酸和对羟基苯甲酸6种酚酸进行定量分析;采用外标法建立了6种酚酸的定量方法,6种酚酸的标准物质在各自质量浓度范围内具有良好线性关系,相关系数为0.991~0.999,检出限为(0.04~8.92)μg/g,平均回收率为85.5%~103.9%,相对标准偏差(RSD)小于2.8%。该方法简便、快速、准确,不仅适合脐橙中酚酸化合物的含量测定,而且对于其他柑橘属植物中酚酸化合物含量的测定也具有一定参考价值。     

4种柠檬不同组织的酚类物质分布及其抗氧化特性

采用分光光度计法评价4种柠檬(尤力克黄柠檬、小青柠、青柠檬、香水柠檬)中果皮与果肉的总酚含量与抗氧化活性(清除ABTS+自由基能力、铁离子还原能力和清除DPPH自由基能力),并用超高效液相色谱对其酚类物质进行定性和定量。结果表明:4种柠檬果皮中的总酚含量及抗氧化活性均显著高于果肉(P0.05),其中尤力克果皮与果肉的总酚、抗氧化活性均显著高于其余3个品种(P0.05),而香水柠檬果皮与果肉中总酚、清除ABTS+自由基能力均最低。不同品种柠檬中酚酸、类黄酮种类及含量差异较大。从4种柠檬中共检出21种酚类物质,其中酚酸6种,黄酮6种,黄烷酮6种,多甲氧基黄酮3种。柠檬中的酚类物质主要是黄烷酮,占类黄酮总量61.82%～91.61%,其中青柠檬果皮中酚酸总量最高(535.62 mg/100 g DW),尤力克果皮中类黄酮总量最高(1 506.33 mg/100 g DW),果肉规律与果皮基本一致,然而其含量显著低于果皮含量(P0.05)。从尤力克果皮与果肉中共检出15种酚类物质,其中圣草枸橼含量最高,而新绿原酸是含量最高的酚酸。从小青柠、青柠檬和香水柠檬的果皮与果肉中分别检测出19,16,15种酚类物质,其中橙皮苷含量均最高,而香草酸是含量最高的酚酸。不同品种柠檬的总酚和总类黄酮含量与ABTS+呈极显著的正相关性,同时总酚含量与DPPH呈显著性的正相关性。     

高效液相色谱法检测不同品种柑橘类果皮多甲氧基黄酮

该文以不同品种柑橘果皮中多甲氧基黄酮(polymethoxy flavonoids,PMFs)的提取检测为目的,建立乙醇索氏提取结合高效液相色谱检测PMFs的方法。结果表明,6种PMFs在2.5μg/mL～500μg/mL范围内线性关系良好(R2≥0.999 5),日内、日间精密度均小于2.8%,方法回收率在97.6%～103.9%之间。采用乙醇索氏提取,提取物经该方法分离检测,对分离后9种不同品种柑橘果皮中PMFs含量进行检测,结果表明,不同品种柑橘果皮中的多甲氧基黄酮含量有明显差异。     

Preparation of free, soluble conjugate, and insoluble-bound phenolic compounds from peels of rambutan (Nephelium lappaceum) and evaluation of antioxidant activities in vitro

The soluble phenolic compounds of rambutan peels (RP) were extracted by microwave-assisted extraction (MAE) and the operating parameters were optimized. The optimal conditions obtained were ethanol concentration of 80.85%, extraction time of 58.39 s, and the ratio of liquid to solid of 24.51:1. The soluble phenolic content by MAE was 213.76 mg GAE/g DW. The free, soluble conjugate, and insoluble-boaund phenolic compounds were prepared by alkaline hydrolysis, and the contents of 3 fractions were 185.12, 27.98 and 9.37 mg GAE/g DW, respectively. The contents of syringic acid and p-coumaric acid were high in the free fraction, showing 16.86 and 19.44 mg/g DW, and the soluble conjugate and insoluble-bound phenolics were mainly composed of gallic acid and caffeic acid. Furthermore, the antioxidant activities of 3 fractions were evaluated in 5 model systems. Results indicated that the free fraction had high antioxidant activities, compared with the soluble conjugate and insoluble-bound fractions.     

Comparison of some biochemical characteristics of different citrus fruits

The goal of this investigation was to evaluate the antioxidant properties of some citrus fruits. The contents of dietary fibre, total polyphenols, essential phenolics, ascorbic acid and some trace elements of lemons, oranges and grapefruits were determined and compared with their total radical-trapping antioxidative potential (TRAP). There were no significant differences in the contents of total, soluble and insoluble dietary fibre in the studied peeled fruits or their peels. The contents of total, soluble and insoluble dietary fibre in peels were significantly higher than in peeled fruits (P< 0.05 in all cases). The peeled lemons, oranges and grapefruits contain 164±10.3; 154±10.2 and 135±10.1 and their peels 190±10.6; 179±10.5 and 155±10.3 mg/100 g of total polyphenols, respectively. The content of total polyphenols in peeled lemons and their peels was significantly higher than in peeled oranges and grapefruits and their peels, respectively. The content of total polyphenols in the peels was significantly higher than in peeled fruits (P< 0.05 in all cases). The same results were obtained in the investigation of essential phenolics and ascorbic acid. The content of Fe in peeled lemons and their peels was significantly higher than in peeled oranges and grapefruits and their peels, respectively. Also the TRAP was significantly higher in peeled lemons and their peels than in peeled oranges and grapefruits and their peels, respectively. In all three fruits, the TRAP was significantly higher in peels than in peeled fruits (P< 0.05). In conclusion, lemons possess the highest antioxidant potential among the studied citrus fruits and are preferable for dietary prevention of cardiovascular and other diseases. The peels of all citrus fruits are rich in dietary fibres and phenolic compounds and suitable for industrial processing.     

Changes of phenolic acids and antioxidant activities during potherb mustard (Brassica juncea, Coss.) pickling

Phenolic acids in potherb mustard (Brassica juncea, Coss.) were determined and the effects of pickling methods on the contents of total free phenolic acids, total phenolic acids, total phenolics, and antioxidant activities were investigated. Gallic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, caffeic acid, p-coumaric acid, ferulic acid, and sinapic acid were identified in the present study. The contents of total free phenolic acids, total phenolic acids and total phenolics in fresh potherb mustard were 84.8 ± 0.58 μg/g dry weight (DW), 539 ± 1.36 μg/g DW, and 7.95 ± 0.28 mg/g DW, respectively. The total free phenolic acids increased during the pickling processes, but the total phenolic acids, total phenolics, and antioxidant activities decreased. However, after 5 weeks of fermentation, all the pickling methods retained over 70% of total phenolic contents and above 65% of antioxidant capacities. The results indicated that pickling processes were relatively good methods for the preservation of phenolic acids and antioxidants for potherb mustard.     

Fatty acids,tocopherols, phenolic and antioxidant properties of six citrus fruit species: a comparative study

Citrus fruit is a rich source of bioactive phytochemicals. Information on the fatty acid and tocopherol composition of locally grown citrus fruits in Korea is elusive. This work was aimed to study fatty acid, tocopherols, ascorbic acid, antioxidant potential, and selected phenolics from peel and pulp of six citrus species. The most dominant fatty acid was linoleic acid (15–45%), followed by linolenic, palmitic, and oleic acid. Stearic acid was highly abundant in yuzu peel (14.45%) and pulp (15.88%) compared to the other fruits. Unsaturated fatty acids (54–74%) contributed higher composition than saturated fatty acids (25–46%). Peel exhibited better antioxidant potential and contained higher phytochemicals than pulp. The concentrations of α-tocopherol and γ-tocopherol were ranged from 22.96 (yuzu) to 86.93 (cheonhyeyang) and 38.59 (yuzu) ~83.03 (tangerine) μg/g DW, respectively. J-Redhyeyang peel exhibited highest total flavonoids (4.17?±?0.10 mgQE/g DW) and DPPH radical scavenging activity (6.17?±?0.03 mgTE/g DW). FRAP values were highest (20.05?±?0.64 mgTE/g DW) in yuzu peel, while peel of cheonhyeyang was superior in total phenolic contents. Tangerine (3.02?±?0.05 mg/g DW) and yuzu (7.49?±?0.38 mg/g DW) had higher hesperidin concentrations in pulp and peel, respectively. Naringin was found in an appreciable amount in yuzu pulp (2.04?±?0.09 mg/g DW) and peel (6.30?±?0.19 mg/g DW) but not detected in all other fruit species. Our results indicate that citrus fruit peel is the rich source of antioxidant compounds, which can be used to prepare antioxidant rich food product.     

Antioxidant activity and phenolic content of 16 raisin grape (Vitis vinifera L.) cultivars and selections

Six raisin grape cultivars and 10 new raisin grape selections were analyzed for antioxidant activity (ABTS assay) and for total and individual phenolic compounds. Samples were freeze–dried and values are reported on a dry weight basis. Antioxidant activity across the 16 samples ranged from 7.7 to 60.9 μmol Trolox/g DW, with A95-27 exhibiting the greatest activity. Total phenolic content, determined in gallic acid equivalents using the Folin–Ciocalteau assay, ranged from 316.3 to 1141.3 mg gallic acid/100 g DW and was strongly correlated (r = 0.990) with antioxidant results. Concentrations of individual phenolics were determined by HPLC. trans-Caftaric acid was the predominant compound in all samples. A95-15 contained the lowest concentration (153.5 μg/g DW) of caftaric acid, while Fiesta contained the highest concentration (598.7 μg/g DW). Selections A56-66, A95-15, and A95-27 had much higher levels of catechin (86.5–209.1 μg/g DW) and epicatechin (126.5–365.7 μg/g DW) than the other samples.     

豆类种子及其芽苗菜的营养品质、功能性成分及抗氧化性研究

为阐明萌发对黑大豆(Glycine max)、红小豆(Vigna angularis)和豌豆(Pisum sativum L)的影响,研究了其种子及萌发后形成芽苗菜的生长特性(总质量、可食部分鲜重、可食率、苗长、含水量)、营养品质(粗蛋白和可溶性糖含量)、功能性成分(总酚、总黄酮含量)和抗氧化性(DPPH自由基清除力、ABTS自由基清除力、FRAP亚铁还原力)。结果表明,3个豆类种子中,黑大豆的营养品质、酚类含量和抗氧化性显著高于红小豆和豌豆。3个豆类芽苗菜以豌豆苗的总质量(12.83 g/10株)、苗长(16.02 cm)和含水量(93.82%)最高;黑大豆芽苗菜的可食部分鲜重(5.87 g/10株)和可食率(71.03%)最高;豌豆苗的可溶性糖含量(0.75 mg/g)、总黄酮含量(7.09 mg/g DW)最高;黑大豆芽苗菜的总酚含量(4.28 mg/g DW)最高、ABTS自由基清除力(110.39μmol/g DW)和FRAP亚铁还原力(75.52 mmol/g DW)最强。萌发显著降低了3个豆类的可溶性糖含量,提高了粗蛋白含量;黑大豆萌发以后酚类含量和抗氧化性显著降低,而红小豆和豌豆萌发后显著提高了其酚类含量和抗氧化性。此外,酚类含量与抗氧化性之间存在着显著的正相关性。因此,黑大豆种子、红小豆芽苗菜和豌豆芽苗菜具有较高的营养价值,含有丰富的酚类物质和抗氧化性。     

Phenolic composition of Flacourtia indica, Opuntia megacantha and Sclerocarya birrea

The phenolic acid composition of the peel and pulp of the fruits of Flacourtia indica (Burm. f.) Merr., Opuntia megacantha (L.) Mill and Sclerocarya birrea (A. Rich.) Hochst., from Zimbabwe, were analysed using traditional colorimetric as well as HPLC methods. The total phenolics, flavanoids and condensed tannin levels varied with species. Sclerocarya birrea pulp had the highest total phenolics, flavanoids and condensed tannins, i.e., 2262 μg GAE/g, 202 μg catechin/g and 6.0% condensed tannins, respectively. Flacourtia indica pulp contained the least total phenolics, flavanoids and condensed tannins 334 μg GAE/g, 41 μg catechin/g and 1.4%, respectively. There were no significant differences in the total phenolics between the peels and the pulps of the individual fruits. However, significant differences were noted in the flavanoids and the condensed tannins between the peels and pulps of the fruits assayed. Ferulic acid, caffeic acid and vanillic acid were the dominant phenolic acids in the three fruits. There were differences between the phenolic acids in the peels and the pulps of the fruits.     

基于HPLC法研究红枣中氨基酸的含量及影响因素

红枣营养成分丰富,富含多种微量元素、氨基酸、酚酸和黄酮,在预防人类疾病、抗衰老和抗氧化方面具有显著的功效。试验使用HPLC法对若羌红枣、河南新郑红枣、哈密红枣、吕梁红枣和交城红枣5种红枣中的氨基酸进行测定和分析,同时对影响红枣中氨基酸含量的采摘日期、干燥方法和保存时间进行分析。研究结果表明,5种红枣中氨基酸含量最高的是交城骏枣(400μg/g DW),氨基酸含量最低的为吕梁木枣(250μg/g DW);随着采摘时间的延长,红枣中的氨基酸含量也逐渐增多;采用低温干燥的方式能够最大程度上保存红枣中的氨基酸;红枣的保存时间在9个月以内,能够最大程度地减少红枣中氨基酸的丧失。该研究为红枣的育种、采摘、烘干和保存提供了一定的理论基础。     

基于HPLC法研究红枣中氨基酸的含量及影响因素

红枣营养成分丰富,富含多种微量元素、氨基酸、酚酸和黄酮,在预防人类疾病、抗衰老和抗氧化方面具有显著的功效。试验使用HPLC法对若羌红枣、河南新郑红枣、哈密红枣、吕梁红枣和交城红枣5种红枣中的氨基酸进行测定和分析,同时对影响红枣中氨基酸含量的采摘日期、干燥方法和保存时间进行分析。研究结果表明,5种红枣中氨基酸含量最高的是交城骏枣(400μg/g DW),氨基酸含量最低的为吕梁木枣(250μg/g DW);随着采摘时间的延长,红枣中的氨基酸含量也逐渐增多;采用低温干燥的方式能够最大程度上保存红枣中的氨基酸;红枣的保存时间在9个月以内,能够最大程度地减少红枣中氨基酸的丧失。该研究为红枣的育种、采摘、烘干和保存提供了一定的理论基础。