Chemical composition of wild and commercial Achillea millefolium L. and bioactivity of the methanolic extract,infusion and decoction

Medicinal plants used in folk medicine are being increasingly studied and used on pharmaceutical, food and nutraceutical fields. Herein, wild and commercial samples of Achillea millefolium L. (yarrow) were chemically characterized with respect to their macronutrients, free sugars, organic acids, fatty acids and tocopherols. Furthermore, in vitro antioxidant properties (free radicals scavenging activity, reducing power and lipid peroxidation inhibition) and antitumour potential (against breast, lung, cervical and hepatocellular carcinoma cell lines) of their methanolic extract, infusion and decoction (the most consumed forms) was evaluated and compared to the corresponding phenolic profile obtained by high performance liquid chromatography and mass spectrometry. Data obtained showed that the chemical profiles of wild and commercial samples, and also their methanolic extract, infusion and decoction were similar, varying only in the quantities found. Commercial yarrow have higher content of fat and saturated fatty acids, proteins, ash, energy value, sugars and flavonoids, while the wild sample revealed higher levels of carbohydrates, organic acids, unsaturated fatty acids, tocopherols and phenolic acids. The heterogeneity among the antioxidant and antitumour results of the samples and some low correlations with total phenolic compounds indicates that specific compounds, rather than the totality of them, are involved in the bioactive properties of samples.     

Influence of technological processes on phenolic compounds,organic acids,furanic derivatives,and antioxidant activity of whole-lemon powder

The healthy properties of citrus fruits have been attributed to ascorbic acid and phenolic compounds, mainly to flavonoids. Flavonoids are important phytonutrients because they have a wide range of biological effects that provide health-related properties. In this context, this study seeks to characterise the phenolic compounds in lemon and their stability in different drying processes (freeze-drying and vacuum-drying) and storage conditions (−18 and 50 °C for 1 and 3 months). A powerful high-performance liquid chromatography coupled to DAD and electrospray-ionization time-of-flight mass spectrometry (HPLC–ESI-TOF-MS) method has been applied for the separation, identification, and quantification of 19 phenolic compounds and 4 organic acids. To our knowledge, two hydroxycinnamic acids have been identified for the first time in lemon. Folin–Ciocalteu was applied to determine total phenolic compounds and TEAC, FRAP, and ORAC were applied to determine the antioxidant capacity of lemon. Total phenolic content significantly differed in the samples analysed, vacuum-dried lemon showing the highest phenolic content, followed by freeze-dried lemon and, finally, vacuum-dried lemon stored at 50 °C for 1 and 3 months. The content in furanic compounds was determined to evaluate the heat damage in lemon and it was showed an increase with the thermal treatment because of the triggering of Maillard reaction. As exception of ORAC, antioxidant-capacity assays were not correlated to phenolic content by HPLC due to the formation of antioxidant compounds during Maillard reaction.     

Effect of drying temperature on the sugars,organic acids,limonoids, phenolics,and antioxidant capacities of lemon slices

Changes in contents of sugars, organic acids, limonoids, phenolics contents, and antioxidant capacities of lemon slices dried at different temperatures were evaluated. Air drying (AD) promoted losses of sugars, citric acid, ascorbic acid, extractable phenolics (EPs), and non-extractable phenolics (NEPs), while it introduced an increase in limonoids. Phenolics of lemon were mainly presented in their extractable form. Hesperidin and eriocitrin were the main EPs; protocatechuic acid and poncirin were the predominant NEPs. The decrease in extractable phenolic acid, EP, and NEP content in lemon is lower at low drying temperatures, while the increase in non-extractable phenolic acid content is higher at high drying temperatures. The antioxidant capacity of EP was higher than that of NEP. Phenolics contributed to antioxidant capacities of lemon slices, and flavonoids were the main contributors among phenolics. Considering limonoids contents and the high levels of EP, NEP, and antioxidant capacities, AD at 60 °C could be an appreciate treatment for dehydrating lemon slices.     

The composition of polyphenols and methylxanthines in teas and herbal infusions

The popularity of tea is increasing on the global aspect because of its role as a significant source of phenolic compounds in human diet. The purpose of this study was to determine and compare the phenolic and methylxanthine composition as well as the antioxidant capacity of white, green, Oolong and black teas, and chamomile and linden infusions depending on the extraction conditions (water temperature and multiple extractions). The content of total phenols and total flavonoids in teas and herbal infusions was determined by using UV/vis spectrophotometric methods, whilst individual polyphenols (phenolic acids and flavan-3-ols) and methylxanthines were identified and quantified by using high performance liquid chromatography coupled with photodiode array detection. In order to determine the antioxidant capacity of teas the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays were applied. The highest content of phenolic compounds was determined in green tea, which also demonstrated the highest antioxidant capacity, whilst herbal infusions were characterised with the lowest content of phenolic compounds, as well as the lowest antioxidant capacity. The highest content of caffeine, as the most abundant methylxanthine, was determined in black tea. Extraction at 100 °C is the most effective to extract the highest content of polyphenols and methylxanthines in all studied teas.     

Effects of brewing process on phenolic compounds and antioxidant activity of herbs

Traditionally used medicinal plants contain a wide range of polyphenolic compounds that act as powerful antioxidants. The content of phenolic compounds in the infusions and decoctions of chamomile (Matricaria chamomilla L.) and St. John’s wort (Hypericum perforatum), which are traditionally used medicinal herbs, was evaluated via liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. To obtain relevant antioxidant/reducing capacity of the prepared extracts, cupric reducing antioxidant capacity and Folin-Ciocalteu assay were applied. Rutin and apigenin were the major flavonoids in the aqueous extract of chamomile, whereas the predominant phenolic compounds of St. John’s wort water extracts were rutin and catechin followed by chlorogenic acid. A longer time of infusion and decoction of St. John’s wort herb significantly affected the rutin content. The increase of extraction time had very little impact on the antioxidant activities for chamomile but considerably higher impact on those for St. John’s wort.     

Contents of phenolics and flavonoids and antioxidant activities in skin, pulp, and seeds of miracle fruit

Miracle Fruit (Synsepalum dulificum) has been studied because of its unique taste modifying properties. This study investigated contents of phenolics, flavonoids, and antioxidant activities in skin, pulp, and seeds of Miracle Fruit. The free phenolic content in skin was almost 3 times of that in pulp and 4 times of that in seeds. Skin contributed 43.96% of free phenolic compounds with 15.91% of freeze-dried solids due to its high phenolic content. As the trend observed for phenolic content, the free flavonoid content in the skin was tremendously higher than that in the seed and pulp. The skin contributed about 52% of total flavonoid with 15.91% of dried solids. On other hand, the differences in the bound phenolic contents were not so distinct among the 3 components. The free antioxidant activities in skin and pulp were comparable, and were significantly higher than that in seeds. Although the antioxidant activities in seeds was considerably lower than that in skin, 49.45% free antioxidant activity, 76.41% bound antioxidant activity, and 58.56% of total antioxidant activity were contributed by seeds due to about 66% of solid of total solids. In general, the results of antioxidant activities using sequential methods were higher than that using direct method. This study suggests that Miracle Fruit is a good source not only for flavor and color, and also antioxidant activity for functional food applications.     

干燥方法对番石榴活性物质含量及抗氧化能力的影响

为研究干燥方式、工艺参数对番石榴活性物质含量及抗氧化能力的影响,采用热风干燥、热风-红外联合干燥、真空干燥和真空冷冻干燥技术,比较其对番石榴总酚、黄酮、抗坏血酸含量、清除1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基能力、清除2,2’-联氮-二（3-乙基苯并噻唑啉-6-磺酸）二铵盐（2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt,ABTS）自由基能力和铁离子还原能力（ferric reducing antioxidant power,FRAP ）以及抑制亚油酸过氧化能力的影响。结果表明,与鲜果相比,干燥后番石榴总酚含量显著增加,黄酮和抗坏血酸含量显著降低（P＜0.05）,抗氧化能力显著降低。真空干燥和真空冷冻干燥得到的总酚、抗坏血酸含量较高,清除自由基及FRAP较高。热风干燥得到的番石榴干制品抑制亚油酸过氧化能力较高。随干燥温度升高,热风和热风-红外联合干燥后的黄酮保留量增加,抗坏血酸含量、清除自由基及FRAP降低。综合来看,真空冷冻干燥和中低温热风干燥（60 ℃和75 ℃）得到的番石榴干制品抗氧化能力较高。Spearman相关性分析表明,DPPH、ABTS、FRAP法测定的抗氧化能力及抗氧化效能综合指数分别与总酚含量的相关系数较高,且DPPH自由基清除能力、抗氧化效能综合指数与总酚含量呈显著正相关（P＜0.05）,说明多酚可能是番石榴干制品主要抗氧化物质。     

Potential of nanofiltration for the concentration of bioactive compounds from watermelon juice

The aim of this study was to evaluate the potential of nanofiltration for the concentration of bioactive compounds of watermelon juice. Lipophilic and hydrophilic antioxidant activities were determined through two assays, ferric reducing antioxidant power and DPPH. The content of lycopene, flavonoids and total phenolic in the concentrate samples increased with the increase in the volume reduction factor. Volume reduction factor of three showed the best performance of concentration, generating the highest values for lycopene, flavonoid and total phenolic contents. Average permeation flux was 2.3 L h^?1 m^?2, with continuous extraction of the concentrate at a volumetric reduction ratio of three. Lycopene showed the highest rejection coefficient (0.99), followed by flavonoids (0.96) and total phenolic content (0.65). The hydrophilic antioxidant activity values in both assays were higher than the lipophilic antioxidant activity values. A highly significant correlation was noted between the contents of flavonoids, phenolic compounds, ascorbic acid, and lycopene and their antioxidant potential in both lipophilic and hydrophilic fractions.     

Effect of adding ascorbic acid and glucose on the antioxidative properties during storage of dried carrot

In this study, carrots were treated with ascorbic acid (0.1%) in a glucose (1.0%) solution (AA-Glu), and then freeze-dried and hot-air-dried to investigate the effects on their antioxidant content after 30 days of storage. The antioxidant components were extracted from the carrot samples using methanol. To assess antioxidative properties, tests measured the samples’ reducing power, α,α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity, and ferrous ion chelating power. The above antioxidative properties of carrot extracts were compared with α-tocopherol and butylated hydroxyanisole (BHA). The analysis of antioxidant compounds included the total amount of ascorbic acid, total amount of phenolics, total amount of flavonoids, and carotenoids. The analysis showed that the samples immersed in AA-Glu solution prior to drying exhibited a higher antioxidative property than those not immersed.     

Antioxidant activity of Portuguese honey samples: Different contributions of the entire honey and phenolic extract

The antioxidant activity of Portuguese honeys was evaluated considering the different contribution of entire samples and phenolic extracts. Several chemical and biochemical assays were used to screen the antioxidant properties of entire honeys with different colour intensity and phenolic extracts: reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity, and inhibition of lipid peroxidation using the β-carotene linoleate model system and the thiobarbituric acid reactive substances (TBARS) assay. The amounts of phenols, flavonoids, ascorbic acid, β-carotene, lycopene and sugars present in the samples were also determined. The highest antioxidant contents and the lowest EC₅₀ values for antioxidant activity were obtained in the dark honey. An analysis of variance was carried out to evaluate the influence of the colour intensity and extraction method in the antioxidant properties and phenolic contents. A discriminant analysis was also performed, giving satisfactory results once the six samples were clustered in six individual groups obtained through the definition of two discriminant analysis dimensions.     

温州蜜柑、椪柑采后酚类物质及抗氧化活性比较研究

通过研究温州蜜蜂柑、椪柑两个常见柑橘品种贮藏期间类黄酮、酚酸类物质及抗氧化活性的变化规律,评价其采后的营养品质。结果表明：贮藏60d后温州蜜柑较好地保持了抗坏血酸含量,而椪柑损失较大。类黄酮类物质较稳定,温州蜜柑中黄烷酮含量贮藏后有所增加,椪柑中则呈缓慢下降趋势,2种柑橘中酚酸类物质贮藏后都有所增加。总酚含量在贮藏前期呈下降趋势,贮藏后期温州蜜柑中总酚含量增加而在椪柑中进一步下降。抗氧化能力与抗坏血酸的变化趋势类似。与椪柑相比,贮藏期间温州蜜柑能更好地保持果实的营养品质及酚类物质,从而保持较高的抗氧化活性。     

Antioxidant compounds and antioxidant capacity of Peruvian camu camu (Myrciaria dubia (H.B.K.) McVaugh) fruit at different maturity stages

The antioxidant capacities of ascorbic acid and phenolic compounds present in camu camu fruit were screened during ripening. Ascorbic acid decreased, and anthocyanin, flavonol and flavanol contents, and DPPH antioxidant capacity increased during ripening. Antioxidant compounds from camu camu were fractionated in two fractions: an ascorbic acid-rich fraction (F-I) and a phenolics-rich fraction (F-II). F-I was the major contributor to the DPPH antioxidant capacity (67.5–79.3%) and F-II played a minor role (20.7–32.5%). A total of 30 different phenolic compounds were detected by HPLC-PAD. The presence of catechin, delphinidin 3-glucoside, cyanidin 3-glucoside, ellagic acid and rutin was elucidated. Other phenolic compounds, such as flavan-3-ol, flavonol, flavanone and ellagic acid derivatives, were also present. For the three ripening stages the flavan-3-ols and ellagic acid group were the most representative phenolic compounds in this fruit. Acid hydrolysis of F-II revealed the presence mainly of gallic and ellagic acids, suggesting that camu camu fruit possesses important quantities of hydrolysed tannins (gallo- and/or ellagitannins). These results confirm that camu camu fruit is a promising source of antioxidant phenolics.     

Valorisation of Crocus sativus flower parts for herbal infusions: impact of brewing conditions on phenolic profiling,antioxidant capacity and sensory traits

Saffron production from Crocus sativus flowers produces large amounts of by-products that may represent an excellent source of polyphenols. The aim of this work was to evaluate infusions originating from different brewing processes and from different saffron flower portions, in terms of both functional and sensory traits. For this aim, total polyphenols and total flavonoids, in vitro antioxidant assays and an untargeted phenolic profiling were applied. In general, tepals showed higher polyphenol and flavonoid content than stamen infusions, and their bioactive content depended more on brewing temperature than brewing time. These findings were consistent with both antioxidant capacity and phenolic profiling. Multivariate statistics highlighted polyphenols discriminating ‘boiled’ vs. ‘cold’ infusions, being mainly flavonoids, phenolic acids and the alkylphenol 5-pentadecylresorcinol (showing a strong down-accumulation at the higher brewing temperatures). Positive correlations could be highlighted between anthocyanins, flavones, flavonols and lignans, and the in vitro antioxidant assays. In general, cold brewing was successful in extracting phenolic compounds and provided better sensory properties, thus indicating that this may represent a valuable strategy to develop saffron-based functional beverages with better consumers' acceptability.     

Phenolic profile and carbohydrate digestibility of durum spaghetti enriched with buckwheat flour and bran

The potential of common buckwheat flour (Supreme) and bran (Farinetta) in improving upon the phenolic and antioxidant properties of durum spaghetti was investigated. The cooking quality and carbohydrate digestibility of products were also studied. Significantly large increments of between 114 and 522% for total phenolic content (TPC), 50 and 242% for total flavonoids content (TFC), and over 359% for 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant activity were recorded for uncooked experimental spaghetti samples over the control. Farinetta contributed more phenolic and antioxidant compounds than Supreme flour. Processing and cooking resulted in decreases in phenolic content and antioxidant activity. Cooking losses of up to 8.8% were recorded for the experimental samples and were higher in Farinetta-substituted products. These were generally higher than that of the control (6.3%). The introduction of buckwheat increased carbohydrate digestibility of products, but at the same time, resulted in an overall lower amount of reducing sugars after 120 min of in vitro hydrolysis. Results show that the phenolic and antioxidant properties of durum spaghetti fortified with buckwheat milling fractions can compare favourably with those of 100% whole buckwheat soba pasta, and at the same time, maintain a higher cooking quality due to the presence of semolina.     

Nutrients,phytochemicals and bioactivity of wild Roman chamomile: A comparison between the herb and its preparations

Roman chamomile, Chamaemelum nobile L. (Asteraceae), has been used for medicinal applications, mainly through oral dosage forms (decoctions and infusions). Herein, the nutritional characterisation of C. nobile was performed, and herbal material and its decoction and infusion were submitted to an analysis of phytochemicals and bioactivity evaluation. The antioxidant activity was determined by free radicals scavenging activity, reducing power and inhibition of lipid peroxidation, the antitumour potential was tested in human tumour cell lines (breast, lung, colon, cervical and hepatocellular carcinomas), and the hepatotoxicity was evaluated using a porcine liver primary cell culture. C. nobile proved to be an equilibrated valuable herb rich in carbohydrates and proteins, and poor in fat, providing tocopherols, carotenoids and essential fatty acids (C18:2n6 and C18:3n3). Moreover, the herb and its infusion are a source of phenolic compounds (flavonoids such as flavonols and flavones, phenolic acids and derivatives) and organic acids (oxalic, quinic, malic, citric and fumaric acids) that showed antioxidant and antitumour activities, without hepatotoxicity. The most abundant compounds in the plant extract and infusion were 5-O-caffeoylquinic acid and an apigenin derivative. These, as well as other bioactive compounds, are affected in C. nobile decoction, leading to a lower antioxidant potential and absence of antitumour potential. The plant bioactivity could be explored in the medicine, food, and cosmetic industries.     

Phenolic acids and flavonoids in leaf and floral stem of cultivated and wild Cynara cardunculus L. genotypes

Ten genotypes, cultivated and wild of Cynara cardunculus L. were evaluated for their content of phenolic acids, flavonoids and their antioxidant activity. The major compounds present in the leaf were luteolin derivatives in globe artichoke and apigenin derivatives in wild and cultivated cardoon. Apart from ‘Cimiciusa di Mazzarino’ (var. scolymus), caffeoylquinic acids represent the main phenolic compounds in the floral stem. In particular, ‘Sylvestris Creta’ (var. sylvestris) and ‘Violetto di Sicilia’ (var. scolymus) show the highest content of caffeoylquinic acid ∼95% of the total measured polyphenols. The antioxidant capacity, in both leaf and floral stem, was qualitatively and quantitatively dependent on the phenolic acid and flavonoid profile. The phenolic acids and flavonoids in normally uneaten parts of wild and cultivated artichoke could be exploited as sources of natural antioxidants.     

Effects of different drying methods on phenolic contents,antioxidant, and tyrosinase inhibitory activity of peach blossoms

Fresh peach blossoms of two varieties were dried by using different methods, which include shade drying, freeze drying, microwave drying and hot air drying (at 30, 60, 90, 120 °C). The effects of different drying methods on phenolic contents, antioxidant and tyrosinase inhibitory activity were evaluated. Among the seven drying treatments, microwave drying yielded the highest contents of total phenolics, flavonoids, anthocyanins, proanthocyanidins and individual phenolic compounds in dried peach blossoms, while hot air drying at 30 °C gave the lowest retention of total phenolics, flavonoids, anthocyanins. As compared with shade drying and freeze drying, hot air drying at 60, 90, 120 °C resulted in higher retention of phenolic content. The highest antioxidant activity in dried peach blossoms was obtained by microwave drying, while hot air drying at 30 °C gave the lowest. The effect of different drying methods on antioxidant activity of dried peach blossoms was consistent with that of phenolic content. The highest tyrosinase inhibitory activity was achieved by hot air drying at 120 °C for variety ‘yingchun’ and 90 °C for variety ‘huangjinmeili’, but there was no significant difference among hot air drying at 60, 90, 120 °C for both varieties. The tyrosinase inhibitory activities of peach blossoms by microwave drying and freeze drying were comparable and much lower than that of shade drying. The results indicated that microwave drying was a desirable method for the preservation of phenolic compounds and antioxidant activity in peach blossoms, while shade drying and hot air drying at high temperature were favorable for tyrosinase inhibitory activity.     

Effects of drying and extrusion on colour,chemical composition,antioxidant activities and mitogenic response of spleen lymphocytes of sweet potatoes

Antioxidative and physiological property changes of freeze-dried, hot air-dried and extruded products made from two different colours of sweet potatoes (yellow and orange) were investigated. The results showed that there were no significant differences of dietary fibre content amongst all the treatments, except that the extruded products of orange sweet potatoes had higher dietary fibre contents. However, the water solubility index (WSI) values and antioxidant content were significantly different between yellow and orange sweet potatoes, and significantly different amongst freeze-dried, hot air-dried and extruded samples. The WSI values of the extruded samples were significantly higher than those of the hot air- and freeze-dried samples. The freeze-dried samples of orange sweet potatoes had more total phenolic compounds, β-carotene, and anthocyanin and had better scavenging effect on DPPH radicals than had freeze-dried yellow sweet potatoes. However, the scavenging effect on DPPH radicals was appreciably greater for hot air-dried than freeze-dried yellow sweet potatoes, but this trend was opposite for orange sweet potatoes. The extrusion process significantly increased the WSI values, scavenging effect on DPPH radicals and total phenolic compounds but decreased the β-carotene and anthocyanin for both yellow and orange sweet potatoes. At lower concentration (25–50 μg/ml), the methanolic extract of freeze-dried yellow sweet potatoes possessed a greater capacity of increasing the mitogenic response than did freeze-dried orange sweet potatoes; at higher concentration (100–200 μg/ml), the proliferation of the lymphocytes increased when stimulated with mitogen Con A for all the samples. This suggests that mitogen Con A selectively promotes T-cell-dependent proliferative activity.     

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。     

Antioxidant activity and antimicrobial effect of berry phenolics--a Finnish perspective

In Finland, berries are part of the traditional diet significantly contributing to the intake of flavonoids and other phenolic compounds. Compositional data on phenolic compounds in berries has been rapidly accumulating and included in the national food composition database. Among the different bioactive substances in berries, phenolic compounds including flavonoids, tannins, and phenolic acids have received considerable interest due to their effects in food and health. A great amount of in vitro evidence exists showing that berry phenolics are powerful antioxidants. However, the antioxidant effect of berry phenolics is strongly dependent on the choice of berry raw material, as the antioxidant activity differs between the different phenolic constituents, including anthocyanins, ellagitannins, and proanthocyanidins. In foods, the antioxidant effect is also influenced by the structure of food. Tannin-containing berries exhibit antimicrobial properties against pathogenic bacteria, thus offering many new applications for food industry. Much of the interest in berry phenolics has focused on cranberries and both cultivated and wild blueberries, although also other berries including black currants, cloudberries, lingonberries, and red raspberries possess promising bioactivities that may have relevance to human health. Antioxidant activity of berry phenolics, in addition to other mechanisms, may contribute to human health, but the possible relationship remains yet to be scientifically substantiated.