Assessment of the antioxidant potential and fatty acid composition of four Centaurea L. taxa from Turkey

This paper focused on the assessment of antioxidant property and fatty acid composition of four Centaurea species. The antioxidant activity of its methanol extract was evaluated by several in vitro experiments including phosphomolybedum assay, DPPH assay, β-carotene/linoleic acid, ferric and cupric reducing power. Total phenolic and flavonoid contents were also evaluated. The methanol extract of Centaurea pulcherrima var. pulcherrima showed the superior free radical scavenging activity, linoleic acid inhibition capacity, reducing power and also had the highest total phenolic content. A significant relationship between antioxidant capacity and total phenolic components was found. The oils of Centaurea taxa were also analysed for fatty acid concentration by gas chromatography. The principal fatty acids in the species were palmitic acid (23.38–30.49%) and linoleic acid (20.19–29.93%). These findings suggest that the Centaurea species could be used as a potential source of new natural antioxidants and unsaturated fatty acids in food industry, cosmetics and pharmaceutical preparations.     

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.     

基于UPLC-Q TOF-MS和HPLC-QQQ-MS技术的赤豆酚类化合物定性、定量分析及其抗氧化能力分析

为深入了解赤豆的营养价值,用80%甲醇溶液提取酚类物质,对提取物中不同存在形态的酚类化合物含量及其抗氧化活性进行测定,并对其80%甲醇提取物中酚类物质进行定性、定量分析。结果表明,赤豆80%甲醇提取物中酚酸含量为3.44 mg/g,黄酮含量为2.50 mg/g,其中3 种存在形式酚类萃取物含量及抗氧化能力不同,糖苷键合态酚酸含量最高,可达1.44 mg/g,游离态黄酮含量最高,可达0.85 mg/g;糖苷键合态亚铁离子还原能力最强,可达15.76 mmol/g,酯键合态1,1-二苯基-2-三硝基苯肼自由基、2,2′-联氮双(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基清除能力最强;80%甲醇提取物通过超高效液相色谱串联四极杆飞行时间质谱仪定性分析,初步鉴定出25 种化合物,包括3 种有机酸、6 种酚酸、16 种黄酮;高效液相色谱串联三重四极杆质谱联用仪定量分析可得,芦丁（327.40 μg/g）、儿茶素类（210.70 μg/g）含量丰富。     

Chemical Composition,Antimicrobial, and Antioxidant Activities of Essential Oil and Ethanol Extract of Coriandrum sativum L. Leaves from Turkey

This study reports the chemical composition, antioxidant, and antimicrobial activity of the essential oil and ethanol extract of Coriandrum sativum L. leaves. Gas chromatography/mass spectrometry analysis identified 19 compounds representing 95.30% of the oil. (E)-2-decenal (29.87%), linalool (21.61%), (E)-2-dodecenal (7.03%), dodecanal (5.78%), (E)-2-undecenal (3.84%), (E)-2-tridecenal (3.56%), (E)-2-hexadecenal (2.47%), tetradecenal (2.35%), and α-pinene (1.64%) were the main components identified in the essential oil. The samples were screened for their antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl radical scavenging and β-caroten bleaching assay. IC₅₀ value for ethanol extract of C. sativum was determined as 74.87 ± 0.03 μg/mL. Total antioxidant activity value for C. sativum ethanol extract was 85.85 ± 0.04%. Total phenolic content for ethanol extract of the plant was determined as 14.97 ± 0.05 mg gallic acid equivalents/g dry weight. The essential oil and ethanol extract were also tested for antimicrobial activity against 28 different foodborne microorganisms, including 19 bacteria, 7 fungi, and 2 yeast species. The ethanol extract of the plant showed weak antimicrobial activities against microbial strains in both disc diffusion and minimal inhibition concentration tests. This study suggested that Coriandrum sativum L. leaves may be used as a potential source of food flavoring, and for their antioxidants and antimicrobial properties.     

基于UPLC-QTOF-MS/MS技术分析荷叶乙酸乙酯相中主要化学成分

采用超高效液相色谱-四极杆飞行时间串质谱技术分析荷叶乙酸乙酯相中的主要化学成分,根据色谱峰的精确分子质量、母离子、碎片离子、质谱裂解规律等信息,结合荷叶中已经鉴定的化合物以及相关参考文献对化合物的结构进行鉴定。从荷叶乙酸乙酯相中共鉴定出40 种化合物,包括27 种黄酮类化合物、6 种酚酸、4 种有机酸、2 种脂肪酸和1 种氨基酸。黄酮类化合物是荷叶乙酸乙酯相中的主要化学成分,主要为槲皮素糖苷、山柰酚糖苷、异鼠李素糖苷和黄酮-3-O-醇类,其次为酚酸。本研究可为荷叶资源在食品加工和功能性食品开发领域的应用提供理论基础。     

Chemical composition and bioactivities of the polyphenolic-rich extract of Ormenis africana Jord. and Fourr

Ormenis africana is an endemic North African species used in folk medicine because of its hypoglycemic property. In this study, the α-amylase and α-glucosidase inhibition and antioxidant activities of the polyphenolic-rich extract from O. africana were determined. The chemical composition was made using liquid chromatography with photodiode array and electrospray ionization mass spectrometry method and the identification of phenolics was assessed by comparing their retention times and ultraviolet and mass spectra with those of the standards and/or reported in the literature. The total phenolic content was estimated by the Folin–Ciocalteu method. The antidiabetic potential was estimated by the determination of α-amylase and α-glucosidase inhibition in vitro. Four assays were used for the evaluation of antioxidant activity of the extracts. Seventeen phenolic compounds were detected. The major peaks are chlorogenic acid, 5-O-di-caffeoylquinic acid, and apigenin and luteolin derivatives. The polyphenolic-rich extract showed remarkable α-amylase and α-glucosidase inhibition activity in a concentration dependent manner. Furthermore, the extract also demonstrated high antioxidant activities. O. africana can serve as a potential natural source for the development of a novel α-amylase and α-glucosidase inhibitory agents against diabetic complications.     

Antioxidant activity and polyphenol content of Turkish thyme (Thymus vulgaris) monitored by liquid chromatography and tandem mass spectrometry

Like tea, the leaves of Turkish thyme (Thymus vulgaris) can be boiled in water to produce an extract. This is widely used as syrup for the treatment of coughs and bronchitis at alternative medicine clinics in many parts of the world. In the current study, we assessed the phenolic content and antioxidant activity of thyme. The antioxidant activities of both ethanol and aqueous extracts of thyme were determined using various in vitro methods. The total phenolic and total flavonoid contents were determined to be a gallic acid equivalent and a quercetin equivalent, respectively. Finally, the quantities of the phenolic compounds were detected using high-performance liquid chromatography and tandem mass spectrometry. The total phenolic compounds in the aqueous extract and ethanol extracts of Turkish thyme were 256.0 μg gallic acid equivalent/mg dried extract and 158.0 μg gallic acid equivalent/mg dried extract, respectively. Conversely, the total flavonoid compounds in both extracts were 44.2 μg and 36.6 μg quercetin equivalent/mg dried extract, respectively. For the first time, we determined phenolic contents and investigated the antioxidant potential of thyme. The results indicate that Turkish thyme is a good dietary source with phenolic properties.     

Antioxidant properties of garden strawberry leaf extract and its effect on fish oil oxidation

The present study characterises garden strawberry leaf extract and reports its effect on shelf life and quality characteristics of fish oil. Radical scavenging capacity of the extract in DPPH^? and ABTS^?+ assays was equivalent to 1207 and 1579 μmol g^?1 of trolox equivalents, respectively, total phenolic content was 257 mg g^?1 of gallic acid equivalents. Phenolic and volatile constituents were analysed by liquid chromatography/mass spectrometry (LC/MS) and gas chromatography/mass spectrometry (GC/MS). The extract was added to fish oil and its oxidation was followed during 42 days: peroxide, p‐anisidine values and hexanal concentration were lower in the samples with extract, particularly at the end of storage. The effect of extract on fatty acid composition was not significant, however the changes in the percentages of some individual acids were observed. Fish oil containing 5% of extract had lower levels of lipid oxidation in comparison to other samples. The results indicate that strawberry leaves could be a potential source of natural antioxidants.     

Composition of flavonoids and phenolic acids in lychee (Litchi Chinensis Sonn.) Flower extracts and their antioxidant capacities estimated with human LDL, erythrocyte, and blood models

Abstract: Lychee (Litchi chinensis Sonn.) flower is a major nectar source in Taiwan. Antioxidant activities of acetone, ethanol, and hot‐water extracts of the flower were estimated through three biochemical models: inhibition of Cu²⁺‐induced oxidation of human low‐density lipoprotein, scavenging ability of oxygen radicals in human blood, and inhibition of human erythrocyte hemolysis induced by peroxyl radicals. Composition and content of flavonoids and phenolic acids in these extracts were also determined by high‐performance liquid chromatography. Results showed that antioxidant effects of all test models as well as contents of flavonoids and phenolic acids for the lychee flower extracts were in the order: acetone extract > ethanol extract > hot‐water extract. Gentistic acid and epicatechin were the major phenolic acid and flavonoid in the extracts, respectively.     

超高效液相色谱串联质谱法测定樱桃酒中的5种酚酸

建立了超高液相色谱-串联四级杆质谱联用(UPLC-MS/MS)技术同时检测樱桃酒中没食子酸、4-羟基苯甲酸、绿原酸、香草酸和咖啡酸5种生物活性酚酸的方法。采用Waters Acquity UPLC BEH色谱柱(100×2.1mm,1.7μm),流动相为甲醇-0.1%甲酸,在梯度条件下进行分析,分析物在负离子模式下用保留时间和质谱信息进行定性,峰面积进行定量,并评价其定量分析的精密度、线性和检出限。结果显示,回收率在82.3%～110.8%之间;相关系数r>0.99,线性关系良好;精密度的相对标准偏差RSD<2.0%,检出限为0.020～0.050mg/L,说明该方法简便、快速、准确、灵敏,可用于樱桃酒中酚酸的检测。此外,实验采用SPSS17.0软件对樱桃酒的理化指标和5种酚酸进行了简单相关分析。     

Screening of Possible In Vitro Neuroprotective,Skin Care,Antihyperglycemic, and Antioxidative Effects of Anchusa undulata L. subsp. hybrida (Ten.) Coutinho from Turkey and Its Fatty Acid Profile

The aim of this work was to determine antioxidant capacities, neuroprotective, skin care, antidiabetic effects, and fatty acid composition of Anchusa undulata subsp. hybrida. The antioxidant activity was screened by four different test systems including total antioxidant, antiradical, reducing power, and metal chelating activities. Neuroprotective potential was determined by anticholinesterase inhibitor assay. Tyrosinase inhibitory activity was tested to detect skin care effect. Antidiabetic effects were evaluated with α-amylase and α-glucosidase inhibitory assays. Inhibitory activities on acetycholinesterase, butyrylcholinesterase, tyrosinase, α-amylase, and α-glucosidase enzymes were observed as 2.238 and 1.239 μmol GALAEs/g, 0.339 mmol KAEs/g, 0.193, and 0.219 mmol ACEs/g extract, respectively. Amount of total phenolics and flavonoids were found as 80.34 μg GAEs/mg and 25.09 μg QEs/mg in the extract, respectively. Twenty-three fatty acids were found in the aerial parts, being oleic acid (24.30 g/100 g of total fatty acids) the most abundant, followed by linoleic (21.19 g/100 g of total fatty acids) and palmitic acids (17.50 g/100 g of total fatty acids).     

Characterization of the phenolic acid profile and in vitro bioactive properties of white beetroot products

The impact of boiling, baking and fermentation treatment on the phenolic acid profile, antioxidant capacity (AC) and angiotensin-1 converting enzyme (ACE) activity of white beetroot was investigated. The phenolic acids were analysed by liquid chromatography–mass spectrometry (micro-HPLC-MS/MS), while AC and ACE were determined by in vitro assays. Phenolic acids concentration was between 87.55 and 100.98 ng g⁻¹ d.m. Ferulic and p-coumaric acids were the main compounds among the nine phenolic acids identified. Boiling increased the phenolic acid content by 3%; however, baking and fermentation reduced the level of these acids by approximately 6% and 11%, respectively. A significant positive correlation was observed between the results of all AC assays and sinapic and caffeic acid content. The ACE inhibitory activity of white beetroot products may be attributable to the combined effect of the syringic, 4-hydroxybenzoic, ferulic and p-coumaric acids. Our study indicates that white beetroot as a novel product may be a valuable source of phenolic acids and functional properties.     

Antioxidant Capacities,Phenolic Contents,and GC/MS Analysis of Rhodiola imbricata Edgew. Root Extracts from Trans‐Himalaya

Our aim was to assess the antioxidant capacities and phenolic constituents of methanol and aqueous extracts of Rhodiola imbricata Edgew. root from Trans‐Himalayan cold desert of Ladakh. The 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS) radical scavenging capacity of the root extracts increased in a dose‐dependent manner (up to 0.1 mg/mL) and root extract concentrations required for 50% inhibition of radical scavenging effect (IC₅₀) were recorded as 0.013 and 0.014 mg/mL (for DPPH) and 0.016 and 0.017 mg/mL (for ABTS) for methanol and aqueous extracts, respectively. The total antioxidant power of the extract was determined by ferric reducing antioxidant power (FRAP) assay. Total polyphenol and phenolic acid content of methanol and aqueous extracts were 112.24, 59.06, 39.02, and 16.95 mg gallic acid equivalent/g of extract, respectively. Total flavonoid and flavonol contents were estimated to be 30.2, 17.67, 20.68, and 7.38 mg quercetin equivalent/g of extract, respectively. In all antioxidant capacity assays, the methanol extract exhibited significantly higher antioxidant capacity than that of aqueous extract due to the presence of significantly higher amount of vital phytoconstitiuents, viz. polyphenol, phenolic acid, and flavonol. GC/MS analysis showed that phytosterols, alkyl halide, phenols, and fatty acid esters were major phytochemical clusters. On the other hand, monoterpenes, fatty acids, tocopherols, aliphatic hydrocarbons, and ethers were found to be present in comparatively less amount in the methanol extract. Hence, our study signifies that this high‐altitude medicinal herb could be used as the natural source of antioxidants and supports its use in traditional system of medicine to ameliorate oxidative stress and high‐altitude maladies.     

Chemical Composition and Antioxidant Activities of Tunisian Thymus capitatus L. Methanolic Extract

Thymus capitatus has traditionally been considered as an anthelmintic, antispasmodic, carminative, emmenagogue, expectorant, rubefactient, sedative, stimulant, and tonic. This work was carried out to determine total polyphenol and total flavonoids chemical composition of phenolics and to evaluate the antioxidant activities of the methanolic extract. Total phenolic contents were assayed using the Folin–Ciocalteu reagent, total flavonoid content was measured spectrophotometrically and phenolics were analyzed by reverse phase–high performance liquid chromatography. The 1,1-diphenyl-2-picrylhydrazyl and reducing power were calculated. Total phenols and total flavonoids varied significantly among the studied regions. Chromatographic analysis by reverse phase–high performance liquid chromatography showed that phenolic acids: tannic, gallic, chlorogenic hemihydrate, caffeic, syringic, ferulic, p-coumaric acid, and trans-cinnamic rosmarinic were the main compounds. The anti-radical activity was region-dependent and could be summarized as follows in ascending order: Boukornine > Kef > Bizerte > Grombelia. Reducing power in the four studied regions was stronger than positive control (ascorbic acid). From these results we have conclude that thyme methanolic extract may have a role in pharmaceutical preparations and preservatives as an antioxidant.     

Antimutagenic and antioxidant activities of cascalote (Caesalpinia cacalaco) phenolics

There is an increasing awareness and interest in the antioxidant behaviour and potential health benefits of phenolic acids. The identification of novel sources of phenolic acids has been also of scientific interest. Cascalote (Caesalpinia cacalaco) pods are known to be a good source of ‘tannins’, the name by which industry in Mexico recognizes phenolic extract. Phenolics were determined as gallic acid equivalents g^?1. The antimutagenic activity against aflatoxin B₁ and the antioxidant activity, using two different methods, of the extract were also evaluated. Gallic acid accounts for almost 90% of the phenolic extract of cascalote, the remaining 10% was tannic acid. Antimutagenic activity of cascalote phenolics was dose‐dependent, showing an inhibition level of 64.42% at the highest dose assayed. Antioxidant and antiradical activities were also dose‐dependent. The highest antioxidant activity showed by cascalote phenolics was 73.5%, higher than that of Trolox. The highest antiradical activity of cascalote phenolics was 75.3%, higher than that of BHT and Trolox. Cascalote pods are an outstanding source of gallic and tannic acids. Copyright © 2004 Society of Chemical Industry     

Effect of defatting and decortication on distribution of fatty acids,phenolic and antioxidant compounds in sorghum (Sorghum bicolor) bran fractions

Sorghum bran components could be a potential source of nutrients and phytochemicals for industrial applications. The effect of defatting with hexane and different degrees of decortication on distribution of fatty acids, phenolic compounds, colour (L, a and b) and antioxidant activity (DPPH) of red (RS) and white (WS) sorghums was studied. The decortication process was carried out at time intervals of 1–6 min. Defatted and nondefatted fractions were analysed. The content of polyunsaturated fatty acids (PUFA) was higher than monounsaturated fatty acids (MUFA); the content of MUFA was higher than saturated fatty acids (SFA). Linoleic, oleic and palmitic acids predominated in all fractions. Significant differences in the content of palmitic and linolenic acids between sorghums were found. RS had higher content of palmitic, and WS was higher in linoleic acid. Defatted samples contained lower amounts of phenolic compounds and higher antioxidant activities, than nondefatted samples. RS was a better source of total phenolic compounds and antioxidant activity compared with WS, but WS presented a more suitable profile of fatty acids. In conclusion, fractions of both types of sorghums can be used in cereal‐based products to enhance their phytochemical profile.     

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.     

Chemical composition and antioxidant activity of oil from wild Achillea setacea and A. vermicularis

The objective of this study was to determine and compare the composition of volatile components of two species, A. setacea and A. vermicularis, under the temperate climatic conditions (north of Iran) and to investigate quantification of fatty acids in the oil extracted using gas chromatography-flame ionization detector and to evaluate the antioxidant potential and the phytochemical profile in terms of phenolic acids and flavonoids content of the oils obtained from the plants. Gas chromatography-mass spectrometry analysis of the essential oils showed that the major compounds of A. setacea were nerolidol (20%) and α-cubebene (14%), while in A. vermicularis were camphor (15%) and borneol (13%). Oil analysis revealed that the major components were palmitic and myristic acids. Chromatographic separation of their phenolic compounds (high-performance liquid chromatography) demonstrated that sinapic, gallic, caffeic, vanillic, syringic, and ferulic acids were present in the two oils of the plants, but in different amounts. These results confirmed A. setacea and A. vermicularis as important sources of bioactive metabolites.     

Comparison and Characterization of Compounds with Antioxidant Activity in Lycium barbarum Using High‐Performance Thin Layer Chromatography Coupled with DPPH Bioautography and Tandem Mass Spectrometry

Methanol extracts from 50 batches of Lycium barbarum (L. barbarum, wolfberry) in China were compared and characterized using high‐performance thin‐layer chromatography coupled with 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) bioautography (HPTLC‐DPPH) and electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry (ESI‐Q‐TOF‐MS/MS), respectively. Results showed that similar components occupying the major antioxidant activity existed in L. barbarum collected from different origins. However, the average antioxidant capacities of methanol extracts of L. barbarum collected in Ningxia were significantly higher than those of Qinghai, Xinjiang, Inner Mongolia, and Gansu, which may contribute to rational use of L. barbarum in China. Furthermore, the chemical structure of compound with the highest antioxidant capacity was tentatively identified as 2‐O‐β‐d ‐glucopyranosyl‐l ‐ascorbic acid using ESI‐Q‐TOF‐MS/MS analysis, which possessed high potentials to be used as an antioxidant biomarker for the quality control of L. barbarum. Results are helpful for the bioactivity‐based quality control of L. barbarum, and beneficial for the improvement of their performance in functional/health foods area, suggesting that HPTLC‐DPPH bioautography with ESI‐Q‐TOF‐MS/MS could be used as a routine approach for quality control of antioxidant components in L. barbarum.     

GC-TOF-MS定性和定量评估5 种木本油料种籽油的脂肪酸

采用气相色谱-飞行时间串联质谱和超临界二氧化碳提取技术,分析评价5 种木本油料种籽油的脂肪酸组成及相对含量。油茶和榛子种籽油中富含油酸,亚油酸是沙棘和文冠果种籽油中的主要脂肪酸,牡丹种籽油中的亚麻酸含量最高。沙棘种籽油的单不饱和脂肪酸与饱和脂肪酸比值为1.57：1,亚油酸与亚麻酸的比值为1.56：1,符合功能性健康食用油的标准;牡丹种籽油是补充人体ω-3脂肪酸的优质食用油;油茶和榛子种籽富含单不饱和脂肪酸,适合食品加工;文冠果种籽油含有3 种长链单不饱和脂肪酸（如神经酸等）。本实验评价了5 种木本油料油脂脂肪酸的组分,对指导企业生产生物活性油和人们的健康消费具有重要意义。