化妆品中雄激素的高效液相色谱-质谱鉴定

目的 建立化妆品中雄性激素睾丸酮、甲基睾丸酮的高效液相色谱-质谱（HPLC-MS）鉴定方法.方法 样品用甲醇萃取后,用液相色谱-质谱分析鉴定,色谱柱为C18,流动相为甲醇：水=80：20（V/V）;流速为0.98 ml/min.质谱电离方式为ESI正模式,采用多级m/z 303的特征碎片离子峰质谱功能.结果 通过优化色谱和质谱仪器条件,选择二级质谱的特征碎片离子,睾丸酮离子峰m/z 289的特征碎片离子峰m/z 271,m/z253,甲基睾丸酮分子离子峰m/z 303的特征碎片离子峰m/z285,m/z267,可以对样品进行准确的定性;采用柱后添加0.2%的甲酸,在相同浓度下,信号强度提高了近20倍.利用该方法对某雄激素疑似阳性的化妆品样品中的睾丸酮、甲基睾丸酮的进行鉴定,结果 为阴性.结论该法特异性高,选择性强,灵敏度高,分析时间短,有较好的重现性,适合对化妆品中雄激素的定性.     

Composition of goat and cow milk produced under similar conditions and analyzed by identical methodology

The aim of this study was to identify, under the best possible conditions, the interspecific differences between the proteins, fat and minerals in goat and cow milk. The protein fractions presented evident differences, especially concerning the amount of α_S1-casein, which was lower in the goat milk (62.8%; P < 0.05). The amino acid profile of the two proteins revealed certain differences, although the total quantity of essential amino acids did not vary (P > 0.05). The composition of fats was well-differentiated, mainly as concerns the content of medium-chain fatty acids (C6–14), which were higher in the goat milk (28.8%; P < 0.05). The same was true for n-6 polyunsaturated fatty acids (10.0%; P < 0.05) and n-3 polyunsaturated fatty acids (51.0%; P < 0.05), and also the total level of conjugated linoleic acid (33.8%; P < 0.05). The quantities of Ca, P, Mg and Cu were greater in the ash derived from goat milk (17.4, 15.6, 16.3 and 66.6%, respectively; P < 0.05). Due to the greater quantity of total solids present in goat milk (16.3%; P < 0.05), all of the above-mentioned differences would be considerably increased by the fact that they refer to the amounts present in a given volume. The differences detected between cow and goat milk mean that the latter constitutes a food of particular interest, in terms of both health and nutrition.     

Identification and quantification of polyphenolic compounds in ten pear cultivars by UPLC-PDA-Q/TOF-MS

The aim of this study was to identify and compare phenolic acids, flavan-3-ols and procyanidins, flavonol glycosides, flavones and hydroquinones in different cultivars of pear. Pear fruits (Pyrus communis L.) of ten cultivars (‘Bonkreta Williamsa’, ‘Carola’, ‘Dicolor’, ‘Faworytka’, ‘Hortensia’, ‘Konferencja’, ‘Lukasówka’, ‘Nojabrska’, ‘Radana’ and ‘Uta’) were used in this study. Sixty-five phenolic compounds, including 26 phenolic acids, 22 flavan-3-ols and procyanidins, 15 flavonols, 1 flavone, and 1 hydroquinone, were determined in the examined samples using the ultra-performance liquid chromatography photodiode detector-quadrupole/time of flight-mass spectrometry (UPLC-PDA-Q/TOF-MS) method. Major differences were found in the phenolic profiles of investigated cultivars. The ‘Radana’ cultivar exhibited the highest total phenolics content (894.9 mg/kg FW) and was characterized by the highest concentration of phenolic acids (503.1 mg/kg FW) and arbutin (70.8 mg/kg FW).     

Determination and evaluation of element bioaccessibility in some nuts and seeds by in-vitro gastro-intestinal method

Element bioaccessibility in some nuts and seeds has been determined by performing a physiologically based extraction test. Nine elements (B, Ca, Co, Cu, Fe, Mn, Mg, Ni and Zn) in gastric and intestinal phase extractions of nuts and seeds were determined using inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry. Hazelnuts, almonds, sunflower seeds, peanuts, cashew nuts, Brazil nuts, walnuts, chickpeas, pumpkin seeds and pistachio nuts were used as the materials in this study. The bioaccessible portions of magnesium and calcium were higher than for the other elements whereas B bioaccessibility was the lowest for each of the different types of nuts and seeds. Based on an ingestion rate of 10 g day⁻¹, the amounts of B, Ca, Co, Cu, Fe, Mn, Mg, Ni and Zn from the nuts and seeds accessible to the body were found to be lower than the Tolerable Upper Intake Levels. The data were also subjected to chemometric evaluation using tools such as Principal Component Analysis (PCA) and Linear Discriminant Analyses (LDA) in an attempt to classify the nuts and seeds according to these elements bioaccessibility and to find out which elements are more bioaccessible in gastric and intestinal ingestions.     

Paper spray ionization mass spectrometry: Study of a method for fast-screening analysis of pesticides in fruits and vegetables

New faster and simpler methods for determination of pesticides in agricultural products are necessary as requirements for food safety are becoming increasingly stringent. One possibility is to introduce a fast, easy and low-cost screening method before liquid chromatography mass spectrometry analyses. We hereby present a systematic proof of concept study of paper spray mass spectrometry method for pesticide detection as a screening method. Two sampling approaches – wiping the surface with paper and applying the sample homogenate directly on the paper – were used. The wiping method was more extensively studied for imazalil and thiabendazole originally present in oranges. For homogenized samples three matrices – oranges, tomatoes and grapes – and five pesticides of different chemical nature and polarity – thiabendazole, aldicarb, imazalil, methomyl and methiocarb – were chosen. It has been shown that limits of detection below maximum residue levels can be achieved for both methods (e.g. imazalil and thiabendazole detection limits were found to be lower than 5 mg/kg). The methods are therefore suitable for fast screening of samples. Moreover, the wiping method was also applied for 11 samples – oranges, grapefruits, lemons, limes, mandarins, tomatoes, apples, pears, strawberries, grapes and sweet peppers – from the local supermarket to screen for different pesticides. Three positive samples for thiabendazole and imazalil and one positive sample for imazalil were found.     

Levels of polycyclic aromatic hydrocarbons in milk and milk powder samples and their likely risk assessment in Iranian population

An MSPE/GC–MS method was used for the measuring of 16 PAHs and assessing of the effect of different factors on PAHs concentrations among different types of dairy products. Moreover, the probabilistic health risk assessment due to ingestion of PAHs by the consumption of milk and milk powder was evaluated. The limit of detection (LOD) and limit of quantitation LOQ were ranged between 0.040-0.075 and 0.121-0.227 μg/kg, respectively. The highest mean of total PAHs was noted in milk powdered (2.28 ± 0.39 μg/kg), while the lowest content was observed in pasteurized milk (0.87 ± 0.18 μg/kg). Except for a few samples of milk powder, the PAHs contents of the other samples was lower than standard limits while the concentration of BaP was lower than of standard levels proposed by EU (0.02-0.06 μg/kg). Considering season effect, the samples in winter had the highest level of PAHs. The percentile 95% actual THQ was the 3.64E-04 value that was lower than 1 value. Hence, the consumers are not at considerable non-carcinogenic health risk while the actual ILCR was 3.53E-03 as higher than 1E-04. Therefore, consumers are at considerable carcinogenic risk. Generally speaking, approaching the control plans for a decrease in the concentration of PAHs in dairy products in order to control carcinogenic health risk is crucial.     

Influence of pro- and prebiotics on gastric,duodenal and colonic bioaccessibility of the mycotoxin beauvericin

Beauvericin (BEA) is a bioactive compound produced by the secondary metabolism of several Fusarium strains and known to have various biological activities. This study investigates the influence of several dietary fibers (galactomanan, glucomannan, citrus fiber, bamboo fiber, carrot fiber, pie fiber, β-glucan, xilan, and cellulose) and probiotic strains (Lactobacillus animalis, Lb. casei, Lb. casei, Lb. plantarum, Lb. rhuminis, Lb. casei casei, Bifidobacterium breve, Bf. Adolescents, Bf. bifidum, Corynebacterium vitaeruminis, Streptococcus faecalis, Eubacterium crispatus, and Saccharomyces cerevisiae) on the minor Fusarium mycotoxin BEA bioaccessibility employing a model solution. The bioaccessibility was determined using a simulated gastrointestinal digestion that mimics the physiological conditions of the digestive tract until the colonic compartment. The determination of BEA in the intestinal fluids was carried out by liquid chromatography–mass spectrometry detection (LC–MS). The reduction of BEA bioaccessibility in the experiments carried out using the prebiotic compounds ranged from 60 to 80%, whereas in the trials carried out using the probiotic strains the bioaccessibility observed ranged from 30 to 85%. A BEA degradation product produced by colonic fermentation was identified using the technique of LC–MS-LIT.     

Profiling gangliosides from milk products and other biological membranes using LC/MS

Gangliosides are an important class of glycosphingolipids involved in numerous biological processes such as neuronal development, host–pathogen interactions and gastrointestinal health. Due to the highly heterogeneous nature and relatively low abundance of gangliosides, characterization of gangliosides in biological membranes is challenging. Existing methods for ganglioside analysis are quite time consuming and require expensive high resolution mass spectrometers. A rapid method combining reversed phase chromatography and mass spectrometry was developed using a triple-quadrupole mass spectrometer operating in multiple reaction monitoring mode. The ganglioside species were separated with a Poroshell 120 EC-C18 column and analysed under the negative ion mode. This method allows a sensitive, specific, and quantitative assay for profiling gangliosides. The method is developed for analysis of gangliosides in the milk fat globule membrane of whole milk and applied to other biological membranes. Application includes the cellular membrane of prostate cancer cells. In summary, the method allows various biological membranes to be screened for over 600 gangliosides from 12 classes (GM1, GM2, GM3, GM4, GD1, GD2, GD3, GD4, GT1, GT2, GT3, and GT4) in less than three hours. In summary, expressed as % of relative amounts: 1.5% GM3, 80.2% GD3, 14.4% GT3, 1.5% GM1, 2.4% GD1 were observed in whole milk; 2.5% GD1, 88.2% GD3, 2.5% GM1, 2.2% GM3, 0.2% GT2, 4.2% GT3 were observed in buttermilk and 10.6% GD1, 55.6% GD3, 1.6% GM1, 12.2% GM3, 19.2% GT3, 0.9% GT4 were observed in colostrum.     

Furan, 2-methylfuran and 3-methylfuran in coffee on the Canadian market

Forty samples of commercially brewed coffee samples from 3 national chains and 48 samples of non-brewed coffee samples were collected from retail outlets located in a single Canadian city and analyzed for furan, 2-methylfuran and 3-methylfuran by headspace gas chromatography–mass spectrometry. Non-brewed samples were analyzed “as is” and some were also analyzed after brewing in the laboratory using several preparation techniques. The three analytes were detected in all samples. The rank order of concentrations for all samples was 2-methylfuran >furan > 3-methylfuran. Ground coffee types sampled included regular ground, decaffeinated and cartridge type coffee; mean furan concentrations for these coffee types were 2200, 2450 and 2360 ng/g; 9470, 10400 and 10700 ng/g for 2-methylfuran; and 447, 463 and 508 ng/g for 3-methylfuran respectively. Mean levels for both regular and decaffeinated instant coffee powders were lower with mean furan concentrations of 233 and 327 ng/g; 1600 and 1800 ng/g for 2-methylfuran and 72.9 and 75.2 ng/g for 3-methylfuran respectively. Commercially brewed coffee types sampled included regular ground, decaffeinated and espresso coffee; mean furan concentrations for these coffee types were 38.7, 53.1 and 157 ng/g; 172, 184 and 583 ng/g for 2-methylfuran; and 6.4, 6.7 and 19 ng/g for 3-methylfuran respectively. Brewing coffee samples in laboratory as per manufacturers’ instructions resulted in 27–85% loss of furans—as compared to not brewed samples, loss of methyl furans exceeded that of furan by 10–15%. Brewed coffee stored/standing for up to 30 min resulted in further losses of furans, from 3 to 47%. Degree of loss was not analyte dependent but was highly influenced by storage conditions.     

液相色谱法快速分析奶粉及液态奶中三聚氰胺

目的建立奶粉及液态奶中三聚氰胺的液相色谱快速测定方法。方法以20％甲醇＋1％三氯乙酸为提取溶液,同时沉淀蛋白质等有机物,旋涡震荡混匀后,于30℃水溶中超声提取,在4℃下以4000r／min超速离心后取上清液经0．45μm滤膜过滤后上机测定;采用10mmol／L己烷磺酸钠＋10mmol／L柠檬酸：乙腈（92：8）为流动相,Agilent TC—C18柱（4．0nm×250mm,5μm）,235nm检测波长,根据保留时间和紫外光谱定性,峰面积定量。结果采用上述提取方式,在给定的色谱条件下,样品液中三聚氰胺与样液基质达到基线分离,精密度试验相对标准偏差〈5％。方法在0．500—100μg／mL范围内线性良好,相关系数为0．9995,在不同奶粉中加标回收率范围81．2％～112．1％。采用本方法测定奶粉和液态奶的检出限分别为2mg／kg和0．5mg／kg。结论应用液相色谱法二极管阵列检测器（LC—DAD）同时进行奶粉和液态奶中三聚氰胺的定性定量分析,样品处理简便快速,检测结果准确可靠,适用于基层检验室开展大批量样品的筛查监测。必要时可采用质谱（LC—MS／MS）进一步确认。     

Chemical characterisation of Malvar grape seeds (Vitis vinifera L.) by ultrafiltration and RP-HPLC-PAD-MS

A combination of fast ultrafiltration clean-up procedure and enhanced resolution RP-HPLC-PAD-MS analytical technique is proposed for the characterisation of low molecular mass extractable phytochemicals from Malvar grape seeds (Vitis vinifera L.). This methodology offers satisfactory resolution of the main procyanidin dimers and some trimers and tetramers. Thirty-nine peaks were identified. Seventeen of them contained 17 unambiguously identified compounds: 3 flavan-3-ol monomers (C, EC and ECG), 6 procyanidin dimers (B₁, B₂, B₃, B₄, B₅ and B₆), 1 procyanidin trimer (C₁), 1 procyanidin tetramer ([EC-(4α-8)-EC-(4α-8)-EC-(4α-8)-EC]), 4 hydroxybenzoic derivatives (gallic and protocatechuic acids, protocatechuic aldehyde and methyl gallate*), 1 amino acid (tryptophan)* and ellagic acid*. The remaining 22 peaks, and 1 of the first 17 contained 26 compounds which were tentatively identified as: 2 procyanidin dimers (A- and B-type), 7 trimers, 3 tetramers, 7 monogalloylated dimers, 2 monogalloylated trimers and 1 digalloylated dimer, besides 1 gallotannin, 1 dihydroflavonol* and 2 ellagitannins, some of them described for first time in V. vinifera species. Flavan-3-ols represented 62.4% of all grape seed constituents, absorbing at 280 nm, whereas the non-flavan-3-ol species accounted for more than one-third of the total extractable grape seed constituents.     

Gas chromatography with mass spectrometry detection and characterization of 27 sterols in two truffle (Tuber) species

Fungal sterols (mycosterols) were investigated in seven samples of both Tuber aestivum and Tuber borchii truffles from Italy, Spain and Romania by means of gas chromatography with mass spectrometry (GC/MS). Sterol contents varied from 130 to 590 mg/100 g dry weight (T. borchii) and 110−420 mg/100 g dry weight (T. aestivum). The sterol pattern of both truffle species was dominated by ergosterol (60–85 %) and brassicasterol (4–33 %). In addition, 25 minor sterols were detected with 27 (n = 3), 28 (n = 17), 29 (n = 3), 30 (n = 2) and 31 (n = 2) carbon atoms (Limit of detection: 2 μg/100 g dry weight). Fourteen minor sterols were described for the first time in Tuber species. Ten minor compounds were detected in all samples in varying abundances, while the others were (i) exclusively detected in all samples of one species (T. borchii: fecosterol, ergosta-8-enol; T. aestivum: 24-methyleneergosta-5,22,24-trienol) or (ii) varied strongly in abundance (≥90 %). Variations in main and selected minor sterols could be partly related to different harvest times. In addition, differences in fungisterol and ergosta-5,7-dienol between the both species were attributed to different pathways in fungal sterol biosynthesis (oneway ANOVA p ≤ 0.01). Our study indicates that sterol pattern analysis could be used to differentiate different Tuber species.     

Determination of phytosterols in oenological matrices by liquid chromatography-atmospheric pressure chemical ionization and ion-trap mass spectrometry

The aim of the present study is the identification of plant sterols and the development of an analytical method that allows for the quantification of such family of compounds in oenological matrices. The application of liquid chromatography-atmospheric pressure chemical ionization ion-trap mass spectrometry (LC-APCI-ITMS) to sterol characterization is a useful tool and was selected to perform this research. Sterol separation was achieved using a C8 column with a mobile phase consisting of water and acetonitrile under gradient conditions and column temperature of 35 °C, which leads to analyte elution in less than 25 min. Retention times, precursor ions and MRM transitions of analytes allowed for the identification and sensitive quantitative determination of phytosterols in oenological matrices at trace levels. The method showed a dynamic linear range over the concentration ranges from 0.02 to 320 mg kg⁻¹ for the different parts of grapes and from 8 to 100 ng mL⁻¹ in case of wine. The most abundant phytosterol in all samples was β-sitosterol. The seeds are the richest source of phytosterols having a great amount of β-sitosterol, 314 mg kg⁻¹ fresh berry mass, followed by stigmasterol, fucosterol and campesterol at much lower concentrations (ranging from 3 to 10 mg kg⁻¹).     

Isotope dilution-liquid chromatography/mass spectrometric method for the determination of riboflavin content in multivitamin tablets and infant formula

Isotope dilution liquid chromatography/mass spectrometry (ID-LC/MS) was developed to measure riboflavin contents in infant formula and multivitamin tablets. ¹³C₄, ¹⁵N₂-riboflavin was used as an internal standard. For infant formula, acid hydrolysis was conducted after spiking internal standard to release bound riboflavin. Free riboflavin in the multivitamin tablets was extracted with distilled water for 3 h at 4 °C. The mass spectrometer was operated in selected ion monitoring mode to observe the collisionally induced dissociation channels of m/z 377 → 243 for riboflavin and m/z 383 → 249 for¹³C₄,¹⁵N₂-riboflavin. The developed method was validated based on tests of repeatability and reproducibility, evaluation of measurement uncertainty, and analysis of available certified reference materials. For infant formula and multivitamin samples, the repeatability was 0.1–0.4% and 0.3–1.2%, and the reproducibility was 1.4 and 1.0%, respectively. The realtive expanded uncertainty of analyzing homogenized sample was ranging 1–4%. Therefore, the developed method showed that it has as a high-order metrological quality. The developed ID-LC/MS method was also tested for the accurate analysis of riboflavin in commercial food products including infant formula, breakfast cereals, milk, and multivitamin tablets.     

Rapid identification and determination of 11 polyphenols in Herba lycopi by HPLC–MS/MS with multiple reactions monitoring mode (MRM)

A new and rapid method was developed for simultaneous identification and determination of 11 polyphenols in Herba lycopi, i.e. rosmarinic acid, protocatechuic aldehyde, protocatechuic acid, caffeic acid, ferulic acid, apigenin, luteolin, quercetin, isorhamnetin, chlorogenic acid and rutin, using high performance liquid chromatography (HPLC) coupled with triple quadrupole mass spectrometry (MS/MS). Quantitation was based on multiple reactions monitoring (MRM) using the precursor → production combination for the determination of 11 analytes. The analysis was performed on an Eclipse Plus C₁₈ column (I.D. 4.6 mm × 100 mm, 3.5 μm particle size). An electrospray ionization (ESI)-tandem interface in the negative mode was employed prior to mass spectrometric detection. With the optimized conditions, the 11 biomarkers were detected properly within 3 min. Limits of detection (LOD) ranged from 0.6 to 2.6 ng/ml. The average recoveries ranged from 95.42 to 101.11% with RSDs ≤ 2.23%. The applicability of this analytical approach was confirmed by the successful analysis of 3 samples. The established method was validated and found to be sensitive and reliable for the determination of 11 analytes in Herba lycopi.     

Carcinogenic and neurotoxic risks of acrylamide and heavy metals from potato and corn chips consumed by the Lebanese population

The present study aims to quantify acrylamide and metals in potato and corn chips and to determine their carcinogenic and neurotoxic risks. Gas chromatography mass spectrometry analysis revealed that the average acrylamide level in potato and corn chips (1756 μg/kg) was 3500-fold higher than the permissible limit for acrylamide in drinking water (0.5 μg/kg). Potato-based chips and baked chips were found to contain 23% and 18% more acrylamide than corn-based chips and fried chips, respectively. The daily consumption of acrylamide from potato and corn chips was found to be 7–40-fold higher than the risk intake for carcinogenesis set by World Health Organization (WHO) but was below the neurotoxic risk threshold. Energy dispersive X-ray fluorescence and thermal atomic absorption analysis revealed that the mean concentrations of zinc, lead and cadmium in corn chips were approximately 1.5-, 1.7- and 2.4-fold higher than the permissible limits set by Food and Agriculture Organization/WHO, respectively. However, the daily intake of these metals was lower than the oral reference dose and the upper tolerable daily intake set by the US Food and Drug Administration. The cancer risk for the Lebanese population from acrylamide exposure estimations appears to be significant, highlighting the need to conduct further epidemiological studies and ensure monitoring of acrylamide levels in food products.     

Liquid chromatography with ultraviolet and dual parallel mass spectrometric detection for analysis of vitamin D in retail fortified orange juice

Samples of vitamin D fortified orange juice obtained from retail food stores were analyzed for vitamin D₃ content using a method developed by combining the best features of two AOAC methods. Detection by ultraviolet absorption at 265 nm was compared to detection by selected ion monitoring (SIM) using atmospheric pressure chemical ionization (APCI) mass spectrometry (MS). Furthermore, an ion trap (IT) mass spectrometer was employed in a ‘dual parallel MS’ arrangement to simultaneously obtain qualitative APCI-ITMS data. The method was applied to 33 samples of 3 national American orange juice brands and 7 samples of 5 other American brands collected using a statistically designed sampling plan as part of the National Food and Nutrient Analysis Program to provide values for the USDA National Nutrient Databank for Standard Reference. Vitamin D₃ values ranged from 1.071 μg/100 g (43 IU/100 g) to 1.663 μg/100 g (67 IU/100 g), with an average across 55 samples analyzed, including duplicates, of 1.4 ± 0.1 μg/100 g (57 ± 5 IU/100 g). The average of the 38 non-zero uniquely identified samples, using the averages of duplicate sets, was 1.4 ± 0.1 μg/100 g (57 ± 5 IU/100 g), indicating that a typical 8 oz. (∼240 mL = 240 cm³) glass of orange juice provided 3.4 ± 0.3 μg (140 ± 10 IU) vitamin D₃.     

Two-phase hollow fiber liquid phase microextraction for preconcentration of pyrethroid pesticides residues in some fruits and vegetable juices prior to gas chromatography/mass spectrometry

A sensitive and reliable extraction method based on two-phase hollow fiber liquid phase microextraction followed by gas chromatography–mass spectrometry has been developed for determination of three pyrethroid pesticides. The various parameters affecting the extraction efficiency were studied via rotatable-centered cube central composite design (CCD). The optimization results showed that speed of agitation, extraction time and ionic strength were significantly important in the extraction process. A response surface equation was derived, and the statistical parameters of the derived model were obtained as R² = 0.9862 and F = 142.46. The response surface plots revealed a separation optimum with 480 rpm speed agitation, extraction time of 41 min and NaCl concentration of 3% (w/v). Method detection limits were obtained in the range of 0.02–0.07 ng/mL, and limits of quantitation were between 0.08 and 0.10 ng/mL. The proposed method was successfully applied for the determination of pyrethroid pesticides in some fruits and vegetable juice samples and satisfactory results were obtained.     

Genetic diversity of folate profiles in seeds of common bean,lentil, chickpea and pea

Folates are water-soluble B vitamins and act as cofactors in many metabolic functions in the human body. Pulses have traditionally been considered as a good dietary source of folates. The objectives of this study were (1) to determine the concentration of folates in four cultivars each of common bean, lentil, chickpea and pea, and (2) to determine the effect of growing location on folate concentration. Six folate monoglutamates were quantified by ultra-performance liquid chromatography coupled with mass spectrometry (UPLC–MS/MS). Total folate concentration ranged from 351 to 589 μg/100 g in chickpea, 165 to 232 μg/100 g in common bean, 136 to 182 μg/100 g in lentil, and 23 to 30 μg/100 g in pea. The 5-methyltetrahydrofolate (5-MTHF) and 5-formyltetrahydrofolate (5-FTHF) folates were most abundant in common bean, lentil and chickpea, whereas 5-MTHF and tetrahydrofolate (THF) were the predominant forms in pea. Significant differences were detected among cultivars for all folates across the pulses, except for 5,10-methenyltetrahydrofolate (5,10-MTHF) in lentil, 5-MTHF in chickpea, and 5,10-MTHF and folic acid (FA) in pea. Significant effects for location and cultivar by location were also observed for the majority of the folates.     

Characterization of phenolics,betacyanins and antioxidant activities of the seed,leaf, sprout,flower and stalk extracts of three Amaranthus species

Hydrophilic extracts from different parts including leaves, stalks, seeds, flowers and sprouts of 3 Amaranthus species (Amaranthus hypochondriacus, Amaranthus caudatus and Amaranthus cruentus) were characterized for their phytochemical profiles including the phenolics and betacyanins by UHPLC and LC–ESI–MS, and their antioxidant activities by FRAP and ORAC assays. The main betacyanins in Amaranthus samples were identified to be amaranthine and isoamaranthine. Eleven phenolic compounds (gallic acid, protocatechuic acid, chlorogenic acid, gentistic acid, 2,4-dihydroxybenzoic acid, ferulic acid, salicylic acid, rutin, ellagic acid, kaempferol-3-rutinoside and quercetin) were identified in the extracts of different parts of Amaranthus. The total phenolic content (TPC) ranged from 1.04 to 14.94 mg GAE/g DW; the total flavonoid content (TFC) ranged from 0.27 to 11.40 mg CAE/g DW; while the total betalain content (TBC) ranged from 0.07 to 20.93 mg/100 g DW. FRAP values ranged from 0.63 to 62.21 μmol AAE/g DW and ORAC ranged from 30.67 to 451.37 μmol TE/g DW. The leaves of Amaranthus showed the highest TPC, TFC, TBC, FRAP and ORAC values; while the seeds and stalks the lowest. There was a strong correlation between TPC, TBC, TFC and the antioxidant activity. The result suggests that all parts of the Amaranthus plant can be a good source of antioxidants.