The Use of HPLC-Derived Phenolic Profiles as a Means of ClassifyingSesbaniaAccessions

Aqueous acetone extracts of mature leaves from 10 accessions of two species of Sesbania plants were prepared and analysed by high-performance liquid chromatography (HPLC). The HPLC phenolic profiles were used to develop a classification rule to distinguish between accessions. Out of the 44 mature leaf samples analysed, 27 had distinctive HPLC phenolic profiles and were successfully assigned to the correct accession. Seedlings of these accessions could be classified to the correct species after 3 months' growth. After 3 months' growth, 8 out of 15 samples could be assigned to the correct accession and, at 6 months, 7 out of 20. However, when accessions with very similar phenolic profiles were grouped together, there was a 100% success rate for classifying the correct accession at 3 months and 80% success rate at 6 months. It was concluded that the method could distinguish between some accessions, or groups of accessions, of Sesbania after 3 months' growth. HPLC phenolic profiling is potentially a relatively rapid, but not uniformly reliable, method for classifying Sesbania accessions.     

单花蜂蜜多酚类物质的抗氧化活性

以5种中国单花原蜜,不同产地的42个样本通过Amberlite XAD-2吸附树脂得到的多酚提取物为原料,采用分光光度法,测定总酚酸和总黄酮含量、还原能力、抗氧化活性(清除DPPH自由基、O2－ ·能力),评估蜂蜜多酚类物质抗氧化活性及蜂蜜品种、颜色和地域差异对清除自由基的影响。结果表明：样本总黄酮含量为(9.41±0.18)～(92.76±0.13)mg/kg;总酚酸含量为(9.10±0.05)～(149.57±0.14)mg/100g;深色枣花蜜抗氧化能力最强,对DPPH自由基、O2－ ·清除作用分别为EC50＝(0.042±0.014)g/mL和EC50＝(0.038±0.009)g/mL。提示蜂蜜的多酚类物质影响抗氧化活性,酚酸、黄酮含量与抗氧化能力呈现正相关系;色深原蜜的酚酸、黄酮含量高于色浅原蜜,抗氧化能力也强于浅色原蜜。     

枣花蜜酚类化合物组成及其抗氧化活性分析

以陕西佳县、府谷、大荔、渭南4 个地区枣花蜜为研究对象,测定其理化指标、酚类化合物含量、体外抗氧化活性、对·OH诱导的pBR322质粒DNA氧化损伤的保护作用及过氧化氢（H2O2）诱导的小鼠淋巴细胞DNA氧化损伤的保护作用。结果表明,枣花蜜总酚含量为196.55～454.95 mg/kg,总黄酮含量为22.03～39.40 mg/kg;高效液相色谱-电喷雾-四极杆-飞行时间串联质谱分析发现枣花蜜中含有15 种酚类化合物,包括4 种酚酸和11 种黄酮类化合物;体外抗氧化实验表明,枣花蜜具有较强的1,1-二苯基-2-三硝基苯肼自由基清除能力（半抑制浓度为38.03～122.81 mg/mL）、Fe2＋络合能力（110.93～158.46 mg/kg）和Fe3＋还原力（166.68～365.06 mg/kg）;此外,枣花蜜对·OH诱导的pBR322质粒DNA氧化损伤有保护作用且能显著降低H2O2诱导的小鼠淋巴细胞DNA氧化损伤。本实验的研究结果可为枣花蜜资源的开发利用提供理论参考。     

Compositional Information Useful for Authentication of Krill Oil and the Detection of Adulterants

Nuclear magnetic resonance (NMR) spectroscopy and chromatography, particularly thin layer chromatography with flame ionisation detector (TLC-FID), were used to investigate fish oil adulteration of krill oil with ethyl esters and triacylglycerol. Natural krill oil has higher levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in phospholipid than in triacylglycerol and so high levels of these omega-3 fatty acids in krill oil triacylglycerol was indicative of adulteration. Carbon (¹³C) NMR detected adulteration of krill oil with 10% or more anchovy oil, while TLC-FID detected levels as low as 1% adulteration with EPA ethyl esters. However, positional distribution of EPA and DHA, as determined using ¹³C NMR, was similar for both fish oil and krill oil, indicating that positional distribution cannot be used to show adulteration. Phosphorous (³¹P) NMR spectroscopy can show adulteration with low cost sources of phospholipid but was not useful for determining adulteration of krill oil with fish oil.     

5个调色葡萄品种酚类物质轮廓分析

对调色葡萄品种'烟73'、 '烟74'、 'Kolor'、 'Tintorera'和'Domfelder'成熟期果实和小规模发酵的葡萄酒进行基本理化指标和酚类物质分析.结果 表明,'Kolor'和'烟73'果实花色苷含量较高,均超过4000 mg/kg(以果实鲜质量计);'Tintorera'和'烟73'果实黄酮醇含量...     

Folin-Ciocalteu比色法测定蜂蜜中总酚酸的含量

采用Folin Ciocalteu比色法 ,测定了 17种不同种类的中国蜂蜜总酚酸的含量 ,结果表明 ,总酚酸浓度在 0 0 0 2～ 0 0 12mg/mL范围内与吸光度值有良好的线性关系 ,样品平均回收率 (n =3 )分别为 98 6% ,98 4%和 10 1 8% ,RSD分别为 0 64 % ,0 81%和 0 5 8%。测定结果显示 :中国蜂蜜总酚酸含量为 (13 3 0± 8 3 )～ (14 84 6± 67 0 ) μg/g ,其中荞麦蜜总酚酸含量最高     

油菜蜜中5种酚类化合物的HPLC-ECD法测定

以油菜蜜为研究对象,建立了一种同时测定油菜蜜中5种酚类化合物的HPLC-ECD分析方法。采用高效液相色谱电化学检测法,以甲醇(A)和2%醋酸(B))水溶液为流动相,梯度洗脱,流速为1.0mL/min;电化学检测器的工作电位为0.8V;柱温为30℃。5种酚类化合物的浓度分别在6.83×10-2-5.46,9.6×10-2-8.67,1.05×10-1-12,9.1×10-2-7.3,1.63×10-1-13μg/mL内与各自的峰面积呈良好的线性关系(r>0.9997)。样品的加样回收率分别为97.4%,98.6%,99.1%,101.6%,99.3%。     

Phenolic Profiles and Antioxidant Properties of Apple Skin Extracts

ABSTRACT:  Lipid oxidation, especially the oxidation of polyunsaturated fatty acids, is a significant issue in the food industry impacting both food quality and health of consumers. Apple skin was investigated as a source of natural antioxidants. The phenolic compound composition and antioxidant properties of 21 selected apple genotypes were evaluated. The lipid stabilizing ability of the apple skin extracts was examined using an aqueous emulsion system of methyl linolenate. The total phenolic concentrations determined by high-performance liquid chromatography tandem mass spectrometry of methanolic extracts of skins of the apple genotypes varied from 150 to 700 mg/100 g DW. The antioxidant capacity measured by Folin–Ciocalteu (16.2 to 34.1 mg GAE/100 g DW), ferric reducing antioxidant power (1.3 to 3.3 g TE/100 g DW), oxygen radical absorbance capacity (5.2 to 14.2 g TE/100 g DW), and percent inhibition of oxidation of methyl linolenate (73.8% to 97.2%) varied among the apple genotypes. The apple skin extracts, specifically the crab apple varieties such as "Dolgo," were revealed to be effective inhibitors of oxidation of polyunsaturated fatty acid in a model system and thus can be considered as a potential source of natural food antioxidants.     

蜂蜜中酚类物质及其抗氧化活性研究进展

酚类物质是蜂蜜中重要的生物活性成分,包括酚酸、黄酮及其衍生物,具有抗氧化活性,可以清除超氧阴离子自由基、过氧亚硝酸盐自由基、脂质过氧化自由基、DPPH自由基、ABTS＋ ·、羟自由基等。本文综述了国内外蜂蜜中酚类物质的提取、检测、主要成分及其抗氧化活性的研究进展,旨在为蜂蜜中酚类物质的开发及应用提供依据。     

A Comprehensive Review on the Main Honey Authentication Issues: Production and Origin

Honey is a highly consumed natural product, not only for its taste and nutritional value, but also for its health benefits. Owing to characteristics that are essentially or exclusively related to the specific region or particular local environment and flora, honey can be classified as a premium product generally perceived as a high‐quality and valued product because of its desirable flavor and taste. Consequently, honey has been a target of adulteration through inappropriate/fraudulent production practices and mislabeling origin. Globally, authentication of honey covers 2 main aspects: the production, with main issues related to sugar syrup addition, filtration, thermal treatment, and water content; and the labeled origin (geographical and/or botanical) and “organic” provenance. This review addresses all those issues, focusing on the approaches to detect the different types of honey adulteration. Due to the complex nature of honey and to the different types of adulteration, its authentication has been challenging and prompted the development of several advanced analytical approaches. Therefore, an updated, critical, and extensive overview on the current and advanced analytical methods targeting markers of adulteration/authenticity, including nontarget fingerprint approaches will be provided. The most recent advances on molecular, chromatographic, and spectroscopic methodologies will be described, emphasizing their pros and cons for the identification of botanical and geographical origins.     

蜂蜜淀粉酶在鉴别蜂蜜掺假中的应用研究

针对蜂蜜掺假和造假的问题，本文通过测定蜂蜜粗蛋白、蛋白质含量和淀粉酶值，研究储存温度和时间对蜂蜜淀粉酶值和蛋白质含量的影响，寻找一种简单有效、客观公正的鉴别真假蜂蜜的方法。比较研究结果表明在高温(37℃、45℃)下贮存，天然蜂蜜的淀粉酶值和蛋白质的含量逐渐下降，而假蜂蜜中的淀粉酶值和蛋白质的含量基本不变。通过跟踪测定蜂蜜淀粉酶值和蛋白质含量的变化可以检测蜂蜜产品的质量，也可以鉴别真假蜂蜜。     

八种水果多酚的定量分析与抗氧化活性研究

本文对比研究了8种水果的果皮、果肉、果汁及全果中维生素C与总酚含量,采用高效液相色谱法测定其多酚种类及含量,并评价其抗氧化活性。8种水果Vc含量从高到低,依次为:番石榴脐橙菠萝=木瓜青苹果=皇冠梨=金桔=芒果;总酚含量最高的水果为芒果;从8种水果中共鉴定出16种多酚类化合物,以绿原酸、儿茶素、表儿茶素、芦丁、杨梅酮和根皮苷含量较高。根据8种水果全果中多酚物质种类与含量,分为4类:(1)脐橙;(2)芒果;(3)金桔;(4)青苹果、皇冠梨、番石榴、菠萝和木瓜;DPPH自由基清除能力从强到弱,依次为芒果番石榴青苹果皇冠梨=金桔=脐橙=菠萝=木瓜;氧自由基吸收能力从强到弱,依次为脐橙番石榴皇冠梨=芒果青苹果=金桔=菠萝=木瓜。本研究可为水果精深加工及功能性食品开发提供理论指导。     

Phenolic Profiles and Total Antioxidant Capacity of Marketed Beers in Serbia

The aim of this research was to determine the total phenolic and flavonoid contents as well as to measure antioxidant activity of 24 different commercial beers consumed in Serbia. The major phenolic acids (gallic acid, protocatechuic acid, 4-hydroxybenzoic acid, 2,5-dihydroxybenzoic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, sinapic acid, salicylic), (+)-catechin, and (-)-epicatechin were also determined by high pressure liquid chromatography method using a photodiode array detector. Gallic acid, ferulic acid, and protocatechuic acid are the most abundant phenolic acids in all samples, followed by (+)-catechin. The total phenolic content was determined using the Folin-Ciocalteu assay. The total flavonoids were measured using spectrophotometrics as the aluminum chloride assay. The results showed that the highest total phenolic and flavonoid contents were established in dark and light beer samples. 2,2-Diphenyl-1-picrylhidrazyl radical scavenging activity, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical cation scavenging activity, and ferric reducing/antioxidant power were used to assess the antioxidant potential of beers. These assays, based on different chemical mechanisms, were selected to take into account the wide variety and range of action of antioxidant compounds present in selected beer samples. All beers showed antioxidant power, but a wide range of antioxidant capacities was observed. Statistical differences between ferric reducing-antioxidant power and the other two antioxidant capacity assays were confirmed. This study will be useful for the appraisal of phenolic profile and antioxidant activities of various beers, and it will also be of interest for people who like drinking this beverage.     

Classification of Honey from Its Bee Origin via Chemical Profiles and Mineral Content

Raw honeys from four different bee species, namely the honey bees and stingless bees, were classified based on its chemical profiles, mineral contents and heavy metals. Chemical profiles including proximate composition, predominant sugars, hydroxymethylfurfural content, and diastase activity were determined following official methods while mineral and heavy metals contents were obtained from atomic adsorption spectrometry (AAS) and inductively coupled plasma-mass spectrometry (ICP-MS) measurements, respectively. Both hierarchical cluster analysis and principal component analysis show high possibility of distinguishing honey by its bee species of honey bees (Apis spp.) and stingless bees (Heterotrigona itama) based on distinctive differences in chemical compositions and mineral contents. Potassium and sodium were the major elements in raw honey samples at average of 904.9 and 617.6 mg/kg, respectively. Honey from stingless bee contained more protein, 0.85 g/100 g and less total sugar of fructose and glucose at 24.99 g/100 g. The information of bee speciation origin of honey bees and stingless bees enhances the identity of honey on the product labelling.     

基质固相分散—高效液相色谱法测定蜂蜜中三种酚类化合物

采用基质固相分散技术处理样品、反相高效液相色谱法同时测定蜂蜜中三种酚类化合物.Diamonsil C18柱,甲醇-水(体积比为45:55)流动相,检测波长275 nm.在0.04 mg/L～16.3 mg/L范围内3组分线性关系良好.方法检出限分别为0.05 mg/kg～0.06 mg/kg.回收率范围:86.88%～90.88%.相对标准偏差分别为2.25%、2.31%、2.48%.     

荞麦蜜酚酸含量的高效液相色谱测定及其抗氧化作用的研究

以中国产荞麦蜜为原料,采用高效液相色谱-电化学检测法(HPLC-ECD)测定其中的原儿茶酸、没食子酸、咖啡酸、丁香酸、p-香豆酸、绿原酸、阿魏酸和鞣花酸等8种酚酸的含量。结果表明,中国荞麦蜜中含有原儿茶酸、没食子酸、咖啡酸、p-香豆酸、阿魏酸等五种酚酸,其含量分别为没食子酸为461μg/100g蜂蜜,p-香豆酸为150μg/100g蜂蜜,咖啡酸为79μg/100g蜂蜜,原儿茶酸为30μg/100g蜂蜜,阿魏酸为39μg/100g蜂蜜。本文还对荞麦蜜酚酸提取物的抗氧化作用进行了研究,结果显示荞麦蜜酚酸提取物对超氧阴离子自由基、羟基自由基、DPPH自由基和脂质过氧化均有抑制作用。     

Sugar and Protein Profiles of Omani Honey from Muscat and Batinah Regions of Oman

Fifty-one samples of Omani honey were analyzed for their contents of glucose, fructose, maltose, and sucrose. The Fructose/glucose ratio and its role in honey crystallization were also studied, as well as the protein content of the honey samples. This study has shown that the mean percentage of reducing sugars lie within the limits set by local Omani legislation. Fructose and glucose represented the largest portion. Maltose and sucrose levels were low 3.62 kg/100 kg and 1.29 kg/100 kg, respectively. Most honey samples did not crystallize after 18 months of storage. Protein content in all samples was low with an average of 2 kg/100 kg. Fructose, glucose, and sucrose levels were higher in summer honey samples (69.7 kg/100 kg) than the winter ones (60.6 kg/100 kg).     

Phenolic Profiles and Contribution of Individual Compounds to Antioxidant Activity of Apple Powders

Apples (Malus domestica L.) are the most common source of phenolic compounds in northern European diet. Besides pectins, dietary fibers, vitamins, and oligosaccharides they contain phenolic compounds of different classes. Apple powders are convenient functional forms retaining significant amounts of phenolic antioxidants. In this study reducing and radical scavenging profiles of freeze‐dried powders of “Aldas,? “Auksis,? “Connel Red,? “Ligol,? “Lodel,? and “Rajka? were determined and phenolic constituents were identified using ultra high‐performance liquid chromatography coupled to quadrupole and time‐of‐flight mass spectrometers. A negative ionization mode was applied and seventeen compounds: phenolic acids (coumaroylquinic, chlorogenic), flavonoids (quercetin derivatives), and procyanidin derivatives (B1, B2, and C1) were identified in all tested apple samples. Total values of Trolox equivalents varied from 7.72 ± 0.32 up to 20.02 ± 0.52 and from 11.10 ± 0.57 up to 21.42 ± 0.75 μmol/g of dry weight of apple powder in FRAP (ferric reducing antioxidant power) and ABTS (2,2‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid) postcolumn assays, respectively. The greatest Trolox equivalent values were determined for apples of “Aldas? cultivar. Chlorogenic acid and procyanidin C1 were the most significant contributors to total reducing and radical scavenging activity in all apple cultivars tested, therefore they could be considered as markers of antioxidant activity.