Nutritional analysis and antioxidant activity of palmyrah (<Emphasis Type="Italic">Borassus flabellifer</Emphasis> L.) seed embryo for potential use as food source

The present study was carried out with ungerminated seed embryos of palmryah to evaluate nutritional quality with respect to minerals and fiber components, total phenols, and antioxidant properties. It is found to be good source of carbohydrate, fiber, fat, amino acids, and protein. Analysis of macro and micronutrient composition showed potent source of sodium, potassium, calcium, magnesium, zinc, and iron. In vitro antioxidant activity was evaluated by different assays, including 2,2-diphenylpicryl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2′azinobis (3-ethylbenzothiozoline-6-sulfonic acid) disodium salt (ABTS^·+) assay, ferric reducing antioxidant power (FRAP) assay, phospomolybdenum reduction assay, metal chelating activity, and hydroxyl radical scavenging activity. The results indicate that this plant seed embryo possesses micro, macro nutrients and antioxidant properties and has nutraceuticals potential for the treatment of malnutrition.     

Antioxidant activities of red pepper (Capsicum annuum) pericarp and seed extracts

In this study, we examined the antioxidant activities of red pepper (Capsicum annuum, L.) pericarp and red pepper seed extracts. The extracts were evaluated by various antioxidant assays, including 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging, superoxide anion radical scavenging, hydroxyl radical scavenging, [2,2′‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulphonic acid)] (ABTS) radical scavenging, ferrous chelating activity, superoxide dismutase (SOD) activity and reducing power, along with the determination of total phenolic and flavonoid contents. All the extracts showed strong antioxidant activity by the testing methods. The red pepper pericarp extract exhibited strong ferrous chelating activity and high scavenging activity against free radicals, including both the hydroxyl and DPPH radicals, but it exhibited weaker scavenging activity for the superoxide anion radical and for SOD. In contrast, the red pepper seed extract exhibited strong SOD activity and high scavenging activity against the superoxide anion radical, but showed weaker ferrous chelating activity, hydroxyl radical scavenging, and DPPH radical scavenging. We observed that the reducing power level and ABTS radical scavenging activity of the red pepper seed were higher than those of the red pepper pericarp at the highest tested concentration. Most of the test results for the red pepper seed and red pepper pericarp extracts increased markedly with increasing concentration; however, the metal chelating, SOD and ABTS radical scavenging activities did not increase with the concentration. Highest total phenolic and flavonoid contents were obtained from the red pepper pericarp extracts. Overall, the red pepper seed and red pepper pericarp extracts were highly effective for the antioxidant properties assayed, with the exceptions of ferrous chelating activity, hydroxyl radical scavenging and SOD activity.     

Phenolic composition and functional properties of wild mint (Mentha longifolia var. calliantha (Stapf) Briq.)

Mints (Mentha species) are widely used as food, medicine, spice, and flavoring agents. At the present work, phenolics profile of infusion and ethanol extract of Mentha longifolia was determined using an RP–HPLC–DAD system. Total bioactive contents, radical scavenging, reducing power, metal chelating, and enzyme inhibitory activities relevant to Alzheimer’s disease, diabetes mellitus, and skin disorders were evaluated. Sixteen phenolic compounds (ten phenolic acids and six flavonoids) were identified in the extracts in which sinapic acid (7132 µg/g extract) and rosmarinic acid (6260 µg/g extract) were the most abundant compounds. Strong antioxidant effects were observed in 1,1-diphenyl-2-picrylhydrazyl radical, 2,2?-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), cupric ion reducing activity, ferric reducing antioxidant power, phosphomolybdenum, and metal chelating assays. Results indicated selective acetylcholinesterase inhibitory activity and high α-amylase and α-glucosidase inhibitory potential. Findings showed that M. longifolia has promising health benefits due to its high concentration of useful phenolic compounds and has great potential for possible applications in the preparation of functional ingredients.     

马兰提取物抗氧化性研究

目的：考查马兰中水提取物和乙醇提取物抗氧化活性。方法：分别以水和乙醇为提取液,探讨马兰中水提取物和乙醇提取物的抗氧化活性,包括还原能力以及清除DPPH自由基、羟自由基、超氧阴离子自由基和H2O2的能力。 结果：提取物主要成分为黄酮类化合物。马兰水提取物的抗氧化活性为：超氧阴离子自由基(IC50 2.2μg/mL)＞H2O2(IC50 2.8μg/mL)＞羟自由基(IC50 5.6μg/mL)＞DPPH自由基(IC50 8.5μg/mL) ＞金属螯合性(IC50 28.0μg/mL)。而马兰乙醇提取物的抗氧化活性为：H2O2(IC50 2.0μg/mL) ＞超氧阴离子自由基(IC50 2.1μg/mL)>羟自由基(IC50 2.5μg/mL)> DPPH自由基(IC50 5.6μg/mL) ＞金属螯合性(IC50 51.2μg/mL)。结论：马兰提取物具有较强的抗氧化活性。     

Antioxidant,Antimicrobial, Antifungal,and Antiradical Activities of Cyclotrichium Niveum (BOISS.) Manden and Scheng

In Turkish kitchen, Cyclotrichium niveum, which is consumed as a dietary supplement, have been extensively used in soup and food for their odor and flavor. The present study examines the possible antioxidant, antimicrobial and radical scavenging capacity of Cyclotrichium niveum (Boiss.) Manden and Scheng. In order to evaluate antioxidant and radical scavenging activity different in vitro methodologies such as 2,2´-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, 1,1-diphenyl-2-picryl-hydrazyl (DPPH·) free radical scavenging, total antioxidant activity by ferric thiocyanate, total reducing power by potassium ferricyanide reduction method, superoxide anion radical scavenging, hydrogen peroxide scavenging, and ferrous ions chelating activities were used. In addition, antimicrobial and antifungal activity of the both extracts tested against twenty five microorganisms. Total phenolic compounds and total flavonoids contents in water extract of Cyclotrichium niveum (Boiss.) Manden. & Scheng (WECN) and ethanol extract of Cyclotrichium niveum (Boiss.) Manden. & Scheng (EECN) were determined.     

Effects of Ultrasound,High Pressure,and Manosonication Processes on Phenolic Profile and Antioxidant Properties of a Sulfur Dioxide-Free Mulberry (<Emphasis Type="Italic">Morus nigra</Emphasis>) Wine

The present investigation aimed to evaluate the effects of ultrasound, high pressure, and manosonication on phenolic profile in correlation to antioxidant properties of aged mulberry wines (AMWs). The results indicated a positive effect of non-thermal processes on total phenol content of the AMW conversely to total anthocyanin content, which was negatively affected by pressurization and manosonication. With regard to total flavonoid content, sonication was found to exert a positive effect. A similar trend was also observed for each of the 18 phenolic compounds quantified. The outcome suggests that these phenolic compounds have potent antioxidant properties. From correlation analysis, phenolic acids were noted to be responsible for 1,1-diphenyl-2-picrylhydrazyl, N,N-dimethyl-p-phenylenediamine, and hydrogen peroxide capacities, while total antioxidant, ferric reducing antioxidant power, reducing power, cupric ion, metal chelating, lipid peroxidation, superoxide anion, 2,2′-azino-bis(3-ethylbenzothiazolin-6-sulfonic acid), nitric oxide, and hydroxyl radical capacities were attributed to flavonols and anthocyanins.     

Isolation and Identification of Antioxidant Compounds from Gynura Bicolor Stems and Leaves

The antioxidant compounds in the stems and leaves of Gynura bicolor were studied. 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assays were employed to evaluate antioxidant capacity. By solvent extraction and Sephadex LH-20 column chromatography in sequence, ethanol extracts of Gynura bicolor stems and leaves were fractionated to obtain their active fractions, which were further separated to obtain 12 compounds: 1–8 from stems, and four, 8–12, from leaves. Their structures were elucidated on the basis of spectroscopic data (nuclear magnetic resonance and mass spectrometry). Among these substances, compounds 1, 2, 3, 4, and 8 with significant antioxidant activity were determined to be responsible active components for stems, and compounds 4, 8, and 12 for leaves.     

栽培菊苣籽总黄酮的细胞毒性及清除羟自由基活性成分的识别

采用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide,MTT)法评价栽培菊苣籽总黄酮对小鼠巨噬细胞RAW264.7的毒性。从总抗氧化能力、清除2,2’-联氮-双-(3-乙基苯并噻唑啉-6-磺酸)二铵盐自由基(2,2’-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt cation radical,ABTS+·)能力、清除O_2~-·能力以及抑制Fe~(2+)诱发的卵黄脂蛋白脂质过氧化能力4个方面评价栽培菊苣籽总黄酮的抗氧化活性,并与常见的抗氧化剂VC和叔丁基对苯二酚(tertbutylhydroquinone,TBHQ)作比较。之后采用高效液相色谱(high-performance liquid chromatography,HPLC)法对栽培菊苣籽总黄酮中清除·OH的活性成分进行了识别。MTT实验结果显示,菊苣籽总黄酮质量浓度为1 mg/mL时,对RAW264.7细胞具有一定的毒性,而当其质量浓度适当减小后,则基本无毒性。抗氧化实验结果表明:栽培菊苣籽总黄酮的总抗氧化活性和清除ABTS~+·的能力弱于VC和TBHQ,但在低质量浓度时,其总抗氧化活性与TBHQ非常接近;在清除O_2~-·方面,活性由强到弱为VC菊苣籽总黄酮TBHQ;在抑制卵黄脂蛋白脂质过氧化实验中,栽培菊苣籽总黄酮强于VC,但弱于TBHQ。HPLC法结果显示,绿原酸比洋蓟素具有更高的清除·OH的活性,且二者对·OH的清除率分别为66.42%和46.00%。     

Comparative Bio-Active Compounds Determination and In Vitro Antioxidant Properties of Newly Developed Soy Mixed Wheat Flour and Traditional Wheat Flour

The aims of this study were quantitative determination of the bio-active compounds and to evaluate the in vitro antioxidant activities of methanolic extract of soy mixed wheat flour and traditional wheat flour. Soy mixed wheat flour was developed by combination of processed soy flour and wheat flour. Total phenolics, flavonoids, tannin, and proanthocyanidin contents of the crude methanolic extract were determined by ultraviolet-visible spectrophotometer. Further individual bio-active compounds were determined by high-performance liquid chromatography-diode array detector and showed (+)-catechin, vanillic acid, caffeic acid, (–)-epicatechin, p-coumaric acid, rutin hydrate, and ellagic acid in soy mixed wheat flour but only rutin in traditional wheat flour. The soy mixed product showed significantly higher concentration of bio-active compounds than traditional wheat flour. Antioxidative activities were measured through different in vitro models: phosphomolybdenum blue method, FeCl₃ reducing power, ABTS scavenging activity, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity, N,N-dimethyl-1,4-diaminobenzene free radical scavenging activity, reducing power, metal chelating power and super oxide scavenging ability. All results of in vitro antioxidant models revealed that the soy product showed significantly higher antioxidant activities than traditional wheat flour. These results suggested that soy mixed wheat flour can play the greater roles than the traditional wheat flour for different physiological activities in human body due to the presence of greater amount of bio-active compounds and can be considered as a potential antioxidant containing flour for human consumption than the traditional wheat flour.     

Antioxidant activities of Salvia miltiorrhiza and Panax notoginseng

Traditional Chinese medicinal herb Salvia miltiorrhiza (SM) and Panax notoginseng (PN) have been widely used for the prevention and treatment of vascular diseases in the clinics. To better understand their mechanisms of pharmacological actions, the in vitro antioxidant activities of extract of Salvia miltiorrhiza (ESM) and extract of Panax notoginseng (EPN) were evaluated with different antioxidant testing systems. Their activities of scavenging superoxide anion radicals, DPPH radicals, hydroxyl radicals, and hydrogen peroxide, chelating Ferrous ion, and ferric ion reducing power were assessed. The results showed that the mechanisms of their antioxidant effects were distinct and diverse. ESM possessed strong reducing power and high scavenging activities against free radicals including superoxide anion, hydroxyl and DPPH radicals, but a weaker scavenging activity for hydrogen peroxide. ferrous ion chelating activity of ESM was undetectable at the tested concentrations. In contrary, EPN exhibited strong ferrous ion chelating activity and high scavenging activities against hydrogen peroxide, hydroxyl radicals, and a weak activity against superoxide anion and DPPH free radicals. EPN did not show any ferric ion reducing power. Since their antioxidant mechanisms are complementary, the combined use of ESM and EPN might be even more beneficial. These antioxidant properties of SM and PN are likely part of the reasons that they are effective in the prevention and treatment of vascular diseases.     

Chemical modification of curcumin: Solubility and antioxidant capacity

The aim of this study was to develop a chemical method for demythylation of curcumin. The methoxy groups reduced solubility and low bioavailability of curcumin. The treatment of curcumin with hydrogen bromide or choline chloride increased cucumin water solubility from 1 mg/mL to 30 or 25 mg/mL, respectively. ¹HNMR spectra showed that the chemical shift of O-methoxy groups at 3.9 ppm disappeared upon chemical treatment of curcumin, and indicated that these groups were removed especially after hydrogen bromide treatment. The antioxidant activity of treated curcumin and untreated curcumin was measured using different in vitro assays (i.e., 1,1-diphenyl-2-picrylhydrazyl and 2,2’-azino-bis (3-ethylbenzo-thiazoline-6-sulfonic acid) radical scavenging, and phosphomolybdenum complex formation). A remarkable increase in 1,1-diphenyl-2-picrylhydrazyl and 2,2’-azino-bis (3-ethylbenzo-thiazoline-6-sulfonic acid) radical scavenging was observed as curcumin-hydrogen bromide > curcumin-Choline chloride > curcumin. The formation of phosphomolybdenum complex was found to increase in the order of curcumin-choline cloride > curcumin-hydrogen bromide > curcumin with EC₅₀ 30, 41, and 114 µg/mL, respectively. In conclusion, hydrogen bromide-treated curcumin could be used as potential antioxidant in new functional foods.     

In vitro antioxidant activities of methanol extracts of five Phyllanthus species from India

In this study, the antioxidant activity of methanol extracts of five plants from the genus Phyllanthus was evaluated by various antioxidant assays, including total antioxidant, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, nitric oxide scavenging, reducing power and metal ion chelating activities. The various antioxidant activities were compared to standard antioxidants such as butylated hydroxytoluene and ascorbic acid. All the extracts showed strong antioxidant activity in all the tested methods. Among the five plants Phyllanthus debilis has been found to possess the highest activity in all tested models, the activity decreased in the order Phyllanthus debilis>Phyllanthus urinaria>Phyllanthus virgatus>Phyllanthus maderaspatensis>Phyllanthus amarus. In addition to the antioxidant activity of these plants, the total phenolic compounds, flavonoids and flavonols were measured in the extracts. A correlation between the antioxidant activity and total phenolic content was observed.     

Determination of in vitro antioxidant activity of fennel (Foeniculum vulgare) seed extracts

In this study, the antioxidant activity of water and ethanol extracts of fennel (Foeniculum vulgare) seed (FS) was evaluated by various antioxidant assay, including total antioxidant, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, metal chelating activities and reducing power. Those various antioxidant activities were compared to standard antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and α-tocopherol. The water and ethanol extracts of FS seeds showed strong antioxidant activity. 100 μg of water and ethanol extracts exhibited 99.1% and 77.5% inhibition of peroxidation in linoleic acid system, respectively, and greater than the same dose of α-tocopherol (36.1%). The both extracts of FS have effective reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities. This antioxidant property depends on concentration and increasing with increased amount of sample. In addition, total phenolic compounds in the water and ethanol extracts of fennel seeds were determined as gallic acid equivalents. The results obtained in the present study indicated that the fennel (F. vulgare) seed is a potential source of natural antioxidant. Although, the tests presented here show the usefulness of FS extracts as in vitro antioxidants it still needs to be that this extracts show their activity in emulsions, biological systems, health implications or dry foods.     

Radical scavenging-linked antioxidant activity of ethanolic extracts of diverse types of extra virgin olive oils

The present study evaluated the radical scavenging-linked antioxidant activity of hexane/80% ethanol extracts from several types of extra virgin olive oils (EVOOs) derived from varieties arbequina, hojiblanca, picual, their blends, and pure olive oil (POO). The antioxidant potential of the olive oil extracts was assessed by radical scavenging assays using DPPH (2, 2-diphenyl-1-picrylhydrazyl), ABTS (2, 2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid), and hydroxyl radical, as well as hydrogen peroxide and superoxide anion inhibitory activities. Electron donating ability (EDA) using DPPH assay of 80% ethanol extracts from EVOOs, except arbequina oil, was significantly higher than POO. EDA was markedly higher in blended and picual EVOOs than the extracts from arbequina and hojiblanca EVOOs (P < 0.05). Similarly, ABTS radical scavenging activity of the extracts from the EVOOs was in order of picual EVOO > blended EVOO > hojiblanca EVOO >or= POO >or= arbequina EVOO. Further, the superoxide anion scavenging activity of blended, picual, and arbequina EVOOs was significantly higher than that of hojiblanca EVOO and POO, which were barely detectable. Hydroxyl radical scavenging activity of arbequina and hojiblanca was higher than that of blended, picual EVOOs, and POO. In addition, hydrogen peroxide scavenging activity of the extracts from blended, arbequina, hojiblanca, picual EVOOs, and POO was 63.1 +/- 3.1%, 44.4 +/- 10.2%, 52.0 +/- 2.7%, 71.8 +/- 2.5%, and 35.7 +/- 10.0%, respectively. Our results indicate that ethanol extracts of several EVOOs contained higher radical scavenging and antioxidant activity than the POO. This antioxidant potential is partly due to the phenolic compounds present in different olive oil grade and is influenced by cultivar type.     

基于陶瓷膜过滤工艺制备甘蔗红糖的多酚组成以及抗氧化研究

为研究基于陶瓷膜过滤工艺制备甘蔗红糖的多酚成分、含量以及抗氧化能力,对广西南宁市扶绥县甘蔗双高基地6个品种甘蔗制备的红糖进行研究。通过测定红糖提取液总酚、总黄酮含量以及单体酚组成,以DPPH和ABTS自由基清除能力以及亚铁离子和铜离子螯合能力为指标对红糖提取物抗氧化能力进行评价。结果表明,不同品种红糖的总酚、总黄酮含量以及抗氧化活性存在显著差异;其中红糖总酚含量范围为2846.21~4073.48 μg/g,总黄酮含量范围为1999.24~2438.63 μg/g,在单体酚分析中,没食子酸是红糖优势酚酸;在抗氧化活性测定中,红糖活性提取液的DPPH、ABTS自由基清除能力以及铜离子螯合能力均大于对照组,表现出较高的抗氧化活性,其中D（GUC23-2）在DPPH自由基清除实验、ABTS自由基清除实验、螯合亚铁离子实验中表现出最好效果;结合相关性分析发现,多酚含量与抗氧化活性具有较高相关性,因此可以初步认为多酚种类以及含量是甄别不同品种红糖抗氧化活性的主要因素。综上所述,甘蔗品种的差异性是引起红糖多酚类物质种类以及含量差异的主要因素,而多酚类物质含量以及组成的差异是造成不同品种红糖抗氧化活性差异的主要原因。     

Purification and identification of antioxidant peptides from corn gluten meal

Corn gluten meal was hydrolyzed by alkaline protease and Flavourzyme to obtain the antioxidant peptides. The antioxidant activities of the hydrolysates or peptides were evaluated by free radical scavenging capacity (1,1-diphenyl-2-picrylhydrazyl/2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt/hydroxyl radical/superoxide radical anion), metal ion (Fe²⁺/Cu²⁺) chelating activity and lipid peroxidation inhibitory capacity. The hydrolysates were separated by ultrafiltration, and those with molecular weight <10 kDa exhibited highest antioxidant activity in all relevant assays. The hydrolysates were subsequently purified by gel filtration chromatography, and fraction F3 showed the highest antioxidant activity. Three peptides were identified from fraction F3 using LC–ESI–Q–TOF MS/MS as Leu-Pro-Phe (375.46 Da), Leu-Leu-Pro-Phe (488.64 Da) and Phe-Leu-Pro-Phe (522.64 Da). These peptides exhibited good free radical scavenging activity and lipid peroxidation inhibitory effect. Thus, corn gluten meal may be used as a potential source of antioxidant peptides for food and nutraceutical applications.     

鲷鱼鳞多肽-木糖美拉德反应产物的制备、结构与功能

探索反应时间、木糖（xylose,Xyl）与鲷鱼鳞多肽（fish scale peptides,FSP）质量比、Xyl与FSP总质量浓度、初始pH值和反应温度对Xyl与FSP美拉德反应的影响,并对在Xyl与FSP质量比1.3∶1、Xyl与FSP总质量浓度78?mg/mL、初始pH?11.85、反应温度100?℃、反应时间4.05?h工艺条件下所得产物进行表征。荧光光谱、红外光谱、游离氨基含量以及N-三（羟甲基）甲基甘氨酸-十二烷基硫酸钠-聚丙烯酰胺凝胶电泳过碘酸Schiff碱染色等结构分析,表明FSP与Xyl经美拉德反应后发生共价交联,肽链结构发生变化且形成了新的化合物;1,1-二苯基-2-三硝基苯肼自由基、2,2’-联氮-二（3-乙基-苯并噻唑-6-磺酸）二铵盐自由基、羟自由基以及还原力测定表明,FSP经美拉德反应后抗氧化活性显著增加（P＜0.05）;多酚氧化酶活性测定及苹果褐变实验表明,鲷鱼鳞多肽美拉德反应产物（FSP-MRPs）具有多酚氧化酶抑制活性,其IC50值为0.54?mg/mL,其可能机理为FSP-MRPs具有Cu2＋螯合特性,其螯合位点与抗氧化基团密切相关。     

Antioxidant activity of Maillard reaction products derived from aqueous glucose/glycine,diglycine, and triglycine model systems as a function of heating time

The purpose of this study was to evaluate the antioxidant activity of Maillard reaction products (MRPs) derived from aqueous glucose/glycine, diglycine, and triglycine model systems as a function of heating time. The pH of MRPs derived from the Glu-G model system decreased markedly as the heating time increased, while MRPs derived from the Glu-Di model system showed the highest increase in absorbance at 420 nm. MRPs derived from the Glu-G model system showed the highest cupric ion chelating ability, while MRPs derived from the Glu-Di model system had the highest ferrous ion chelating activity. MRPs derived from the Glu-Di model system were found to be effective antioxidants in different in vitro assays with regard to the 2,2′-azinobis(3-ethylbenothiazoline-6-sulphonic acid) diammonium salt (ABTS) and 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging activities and ferric reducing/antioxidant power (FRAP).     

石榴花色苷的微波辅助提取及抗氧化活性研究

以陕西临潼甜石榴为试验材料,通过正交试验,采用pH 差示法测定石榴总花色苷含量,优化微波辅助提取石榴花色苷的工艺参数。同时,采用DPPH 法、FRAP 法、ABTS 法、螯合亚铁能力法分析石榴花色苷的体外抗氧化活性。结果表明：微波辅助提取石榴花色苷的最佳工艺参数为溶剂pH1、料液比1:13(g/mL)、提取时间210s、乙醇体积分数70%、微波输出功率360W。此条件下,花色苷得率为184.81μg/g。微波输出功率对石榴汁花色苷的提取得率有显著影响(P ＜ 0.05)。石榴花色苷含量与DPPH 自由基清除率、铁还原力、ABTS+ 自由基清除率和螯合亚铁离子有显著的相关性(相关系数R2 分别为0.9928、0.9925、0.9913、0.9945),呈明显的量效关系,IC50 值分别为2.44、1.14、4.08、101.05mg/L。     

Chemical composition and in vitro antioxidant evaluation of a water-soluble Moldavian balm (Dracocephalum moldavica L.) extract

The chemical composition and antioxidant properties of a water-soluble extract of Moldavian balm (Dracocephalum moldavica L., syn. Moldavian dragonhead) prepared by hydrodistillation are presented in this study. The total phenol content was estimated as gallic acid equivalents by the Folin-Ciocalteu reagent method, while the qualitative-quantitative composition of the extract was determined by high performance liquid chromatography coupled with photodiode array detection. The antioxidant properties assessed included iron(III) reduction and iron(II) chelation and 1,1-diphenyl-2-picrylhydrazyl, 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonate) and superoxide anion free radical scavenging. In addition, the ability of the extract to protect 2-deoxy-d-ribose and bovine brain-derived phospholipids against hydroxyl radical-mediated degradation was assessed. The extract principally contained polar compounds including hydroxycinnamic acids and flavonoids, with caffeic and ferulic acids, luteolin-7-O-glucoside, rosmarinic acid, luteolin and apigenin being identified from their chromatographic behavior and spectral characteristics. The Moldavian balm extract demonstrated activity in all the antioxidant assays; however, it was not as potent as the positive control except in the phospholipid-based assay where its hydroxyl radical scavenging activity was statistically indistinguishable from that demonstrated by Pycnogenol.