Bioactive compounds and antioxidant potential of mango peel extract

Bioactive compounds such as polyphenols, carotenoids and anthocyanins present in fruits and vegetables are receiving increased attention because of their potential antioxidant activity. Consumption of such antioxidants offers health benefits including protection against cardiovascular diseases and cancer. Mango peel is a major byproduct obtained during the processing of mango products such as mango pulp and amchur. In the present study, the antioxidant activity of mango peel extracts was examined. Polyphenol, anthocyanin and carotenoid contents in acetone extract of peels were determined. Ripe peels contained higher amount of anthocyanins and carotenoids compared to raw peels while raw mango peel had high polyphenol content. Antioxidant activity of ripe and raw mango peels extracted in acetone was determined using different antioxidant systems such as reducing power activity, DPPH free radical scavenging activity, iron induced lipid peroxidation of liver microsomes and soybean lipoxygenase inhibition. The IC₅₀ values were found to be in the range of 1.39–5.24 μg of gallic acid equivalents. Thus, the mango peel extract exhibited good antioxidant activity in different systems and thus may be used in nutraceutical and functional foods.     

Optimization of Ultrasonic-Assisted Extraction of Polyphenols,Anthocyanins, and Antioxidants from Raspberry (Rubus coreanus Miq.) Using Response Surface Methodology

Ultrasonic-assisted extraction (UAE) was employed for highly efficient extraction of polyphenols, anthocyanins, and antioxidants from raspberry. Process variables were investigated, including ethanol concentration, sonication time, and extraction temperature. A central composite design consisting of three variables and five levels was used to assess the significance of each process variable in UAE applied to raspberry. Analysis of variance confirmed the ethanol concentration as the most significant variable, and reduction of anthocyanins was not observed during UAE. Optimal UAE conditions were an ethanol concentration of 36.2 %, extraction time of 12.84 min, and temperature of 50 °C estimated using overlapped contour plots, which gave predicted maximal values for total polyphenol content (48.67 mg gallic acid equivalent/g), total anthocyanin content (15.23 mg cyanidin-3-glucoside equivalent/g), and antioxidant activity (253 μmol/L trolox equivalent). Verification experiments were carried out under optimal conditions, and good agreement was found between estimated values and experimental values, suggesting that the fitted model was valid and accurate for the UAE process.     

Jaboticaba (Plinia trunciflora (O. Berg) Kausel) fruit reduces oxidative stress in human fibroblasts cells (MRC-5)

Jaboticaba species (Plinia sp.) have attracted attention because of their significant levels of phenolic compounds, primarily anthocyanins and flavonols. Jaboticaba, termed the Brazilian berry, has emerged as a new functional food with potential health benefits. Plinia trunciflora (O. Berg) Kausel is one of the main species of jaboticaba that is naturally occurring and cultivated in Brazil. Thus, this study aimed to determine the macronutrient and phenolic compositions of P. trunciflora pulp and peel. Additionally, jaboticaba peel extract (JPE) was evaluated for its in vitro antioxidant activity and its capacity to modulate oxidative stress as well as mitochondrial function in human lung fibroblast cells (MRC-5). The macronutrient found to have the highest level in both the peel and pulp was carbohydrates, followed by the high fiber content of the peel. The total phenolic compounds and anthocyanin levels were higher in the peel than in the pulp. High resolution mass spectrometry (HRMS) showed the presence of cyanidin-3-O-glucoside and kaempferol. Moreover, JPE was able to reduce the decreases in complex I activity and the ATP levels induced by H₂O₂ and thereby decreased the oxidative stress in MRC-5 cells. These findings show a new role for jaboticaba as a mitochondrial protectant in pathological conditions where mitochondrial dysfunction is involved.     

响应面试验优化石榴皮多酚提取工艺及石榴不同部位多酚的抗氧化活性分析

以石榴皮为原料,通过单因素试验及响应面试验优化石榴皮多酚的最佳提取工艺条件为：乙醇体积分数40%、超声波功率250 W、浸提温度60 ℃、料液比1∶27.5（g/mL）、超声时间39.3 min。此工艺条件下的多酚提取量为（1.13±0.26）mg/g。在优化条件下分别对石榴皮、石榴瓤和石榴籽中的多酚类化合物进行提取并比较其抗氧化活性,得到石榴不同部位的抗氧化活性大小依次为石榴皮＞石榴籽＞石榴瓤;进一步研究了人工模拟胃肠液对抗氧化活性最强组分石榴皮多酚活性的影响,发现经人工胃液处理后,石榴皮多酚的抗氧化活性升高（P＜0.05）,而经人工肠液处理后其抗氧化活性降低（P＜0.05）,推断石榴多酚类化合物在模拟胃肠液条件下其结构和功能的变化是不同的。     

‘蓓蕾’蓝靛果中花色苷组成鉴定及抗氧化能力比较分析

对蓝靛果中花色苷的组成进行鉴定,并对其抗氧化能力进行比较分析。实验以蓝靛果（‘蓓蕾’品种）为原料,采用有机溶剂60%乙醇（0.1%盐酸酸化）溶液,超声辅助提取90 min;利用D101大孔树脂对获得的粗提物进行纯化,之后冷冻干燥制得粉末物质。通过pH示差法和福林-酚法分别测定总花色苷含量和总多酚含量,分别为（353.35±0.79）、（474.01±2.12）mg/g;并用高效液相色谱-质谱联用法对花色苷组成进行鉴定,共发现11 种花色苷,其中矢车菊-3-葡萄糖苷为主要花色苷（90.679%）。此外,实验还通过总抗氧化能力测定和2,2’-联氨-二（3-乙基苯并噻唑-6-磺酸）二铵盐自由基、1,1-二苯基-2-三硝基苯肼自由基清除能力测定,比较分析蓝靛果花色苷提取物、矢车菊-3-葡萄糖苷、VC的抗氧化能力,结果表明,3 种物质的抗氧化能力排序为：矢车菊-3-葡萄糖苷＞花色苷提取物＞VC。     

Optimization of microwave-assisted extraction of anthocyanins from mulberry and identification of anthocyanins in extract using HPLC-ESI-MS

Anthocyanins are naturally occurring compounds that impart color to fruits, vegetables, and plants. This study aims to optimize the microwave-assisted extraction (MAE) conditions of anthocyanins from mulberry (M. atropurpurea Roxb.) using response surface methodology (RSM). A Box-Behnken experiment was employed in this regard. Methanol concentration, microwave power, and extraction time were chosen as independent variables. The optimized conditions of MAE were as follows: 59.6% acidified methanol, 425 W power, 25 (v/w) liquid-to-solid ratio, and 132 s time. Under these conditions, 54.72 mg anthocyanins were obtained from 1.0 g mulberry powder. Furthermore, 8 anthocyanins were identified by high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) in mulberry extract. The results showed that cyanidin-3-glucoside and cyanidin-3-rutinoside are the major anthocyanins in mulberry. In addition, in comparison with conventional extraction, MAE is more rapid and efficient for extracting anthocyanins from mulberry.     

Peel Effects on Phenolic Composition,Antioxidant Activity,and Making of Pomegranate Juice and Wine

Pomegranate peel was used in juicing to find out its effects on the juice products’ (storable juice and wine) sensory property, polyphenols composition, and antioxidant ability. Macroporous resin was used to purify the polyphenols, and 6 different in vitro assays were used to comprehensively determine the antioxidant activity of each. The results showed that juicing with peel made the juice bitter and astringent, but contributed better sensory quality to wine. Peel contributed higher total polyphenols and flavonoids, but lower anthocyanins to the juice products, and caused the phenolics content to fluctuate more dramatically during making wine than the storable juice. Polyphenols purified from the juice products containing peel showed higher total reducing ability and 2,2‐diphenyl‐1‐picrylhydrazyl and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid radical elimination abilities, but their clearance activity of hydroxyl radicals was not positive, and their superoxide anion radical elimination ability showed no significant difference when compared to polyphenols purified from juice products without peel.     

野生蓝果忍冬多酚鉴定及其抗氧化、降血糖活性

目的：对野生蓝果忍冬进行多酚成分鉴定和抗氧化、抗淀粉酶活性研究。方法：以我国小兴安岭地区的野生蓝果忍冬果实为材料,通过固相萃取技术分离纯化得到花色苷和非花色苷分离液,测定分离液中的化学成分,并测定多酚粗提液中总酚和总花色苷含量,抗氧化活性（1,1-二苯基-2-三硝基苯肼自由基清除能力、铁离子还原能力、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、氧自由基吸收能力）,抗α-淀粉酶、α-葡萄糖苷酶活性和脂肪酶活性。结果：野生蓝果忍冬果实中含有丰富的花色苷和非花色苷多酚,尤其是矢车菊素-3-葡萄糖苷和山柰酚-3-芸香糖苷含量很高;蓝果忍冬多酚粗提液中总酚含量为82.7 mg/100 g,总花色苷含量为49.8 mg/100 g,具有较强的抗氧化活性;对α-淀粉酶、α-葡萄糖苷酶活性的半抑制质量浓度分别为0.39 mg/mL和0.933 mg/mL,对脂肪酶活性的半抑制质量浓度为12.31 mg/mL,说明蓝果忍冬可以作为一种有前景的淀粉酶抑制剂。     

不同提取方法对万寿菊花中总多酚和总花色苷动力学模型对比研究

以万寿菊花为原料,首先采用二阶速率模型评价不同料液比经热回流提取(hot reflux extraction,HRE)、超声波辅助提取(ultrasound-assisted extraction,UAE)和微波辅助提取(microwave-assisted extraction,MAE)万寿菊花中总多酚的提取动力学。其次在最佳料液比下,探究3种提取方式对万寿菊花中总花色苷以及提取物总抗氧化活性的动力学。结果表明:在3种提取方式下,获得的万寿菊花总多酚、总花色苷和总抗氧化活性的试验值和模拟值拟合较好,回归系数(R2)均高于0.90,残差平方和均低于0.25。在HRE、UAE和MAE方式下获得的最佳料液比分别为1∶20、1∶50、1∶30(g/mL)。采用UAE获得的总多酚、总花色苷以及抗氧化活性均高于HRE和MAE。     

蔓越莓花色苷的组成鉴定及抗氧化能力

对蔓越莓花色苷的组成进行鉴定,并对其抗氧化能力进行测定。采用pH示差法测定花色苷提取量,超高压辅助提取蔓越莓花色苷含量为（75.49±0.43）mg/100?g,常规溶剂提取蔓越莓花色苷含量为（67.31±1.08）mg/100?g,蔓越莓中总花色苷含量为（79.52±0.50）mg/100?g;选择AB-8大孔树脂对蔓越莓花色苷粗提物进行纯化,冻干粉中花色苷含量从（46.10±0.92）mg/g提高到（309.26±2.37）mg/g。通过测定1,1-二苯基-2-三硝基苯肼自由基清除率、2,2’-联氮基-双-（3-乙基苯并噻唑啉-6-磺酸）二铵盐自由基清除能力和总抗氧化能力,比较蔓越莓花色苷与VC的抗氧化能力。结果表明：同质量浓度条件下,蔓越莓花色苷的抗氧化能力强于VC。通过高效液相色谱-质谱联用技术在蔓越莓中鉴定出7?种花色苷：芍药素-3,5-二己糖苷、矢车菊素-3-半乳糖苷、矢车菊素-3-葡萄糖苷、矢车菊素-3-阿拉伯糖苷、芍药素-3-半乳糖苷、芍药素-3-葡萄糖苷、芍药素-3-阿拉伯糖苷,其中芍药素-3,5-二己糖苷首次在蔓越莓中被鉴定出。     

Physicochemical and bioactive properties evolution during ripening of ‘Ambrunés’ sweet cherry cultivar

The purpose of this paper is to present a study of the development of the principal bioactive compounds and the physicochemical properties of the ‘Ambrunés’ Picota sweet cherry cultivar during its ripening. 5 categories of edible ripeness (termed ’ripening stages’) were determined according to the skin colour. The results show significant increases during ripening in weight, calibre, soluble solids content, fructose, total phenols, total anthocyanins and total antioxidant activity; a non-significant decrease in firmness; and significant decreases in the colour parameters of both skin and flesh and in glucose. The following compounds were identified and quantified using HPLC-DAD/ESI-MS: 5 anthocyanins, of which the most abundant was cyanidin-3-O-rutinoside; 3 hydroxycinnamic acids, principal of which was p-coumaroylquinic acid; a flavonol (rutin); and a flavan-3-ol (epicatechin), which was the least abundant of all the phenolic compounds. Because of the increased levels of bioactive compounds associated with it, ripening stage 5 was considered to represent the highest nutritional and functional quality.     

山竹果皮浸泡酒的活性成分及抗氧化活性变化

以山竹果皮为原料制备浸泡酒,研究果皮浸泡过程中多酚、黄酮、花色苷等活性物质含量及色度的动态变化,并以DPPH自由 基清除能力和铁离子还原能力（FRAP）为评价指标,探讨山竹果皮浸泡酒浸泡期间抗氧化活性变化。 结果表明,果皮浸泡过程中活性 成分溶出量均随浸泡时间的延长而增加,且烘干样品效果较好。 其中花色苷含量在浸泡3 d时较高,为1.76 mg/L;黄酮、多酚含量在浸 泡7 d时较高,含量分别为2.43 mg/mL、480.82 μg/mL;浸泡5 d时酒色度达到最高,为0.34。 抗氧化活性实验结果表明,在浸泡过程中, DPPH自由基清除率在第3天达到稳定,为77.77%,而还原能力在第7天达到稳定,为6.422×10-4 mmol。 因此,烘干的山竹果皮用白酒浸 泡7 d后,得到的酒液中主要活性成分含量较高,抗氧化作用较好。     

雪莲果皮多酚提取工艺及其抗氧化、抑菌活性的研究

以雪莲果皮为试验材料,以多酚提取率为指标,在单因素试验的基础上,采用正交试验法对超声辅助提取雪莲果皮多酚工艺参数进行优化,通过扫描电镜分析不同提取方式对雪莲果皮粉末表面微观形态的影响和提取得率的关系,同时评价雪莲果皮多酚的抗氧化活性及抑菌活性。结果表明最佳提取条件为:料液比1:35(g/mL)、提取温度65 ℃、乙醇体积分数40%、提取时间55 min。在此优化条件下,雪莲果皮多酚的提取率为193.87 mg/g;扫描电镜分析显示物料的破碎程度为:超声波提取法>加热回流法>浸提法>原材料粉末;抗氧化试验结果表明雪莲果皮多酚3 mg/mL浓度下对DPPH·清除能力为70.23%,IC₅₀值为0.71 mg/mL;对ABTS⁺·清除能力为97.96%,IC₅₀值为0.68 mg/mL;5 mg/mL浓度下总抗氧化能力为46.28 μmol Trolox/mL;抑菌试验结果表明雪莲果多酚对大肠杆菌和金黄色葡萄球菌均有一定的抑制作用,供试菌种的最小抑菌浓度(MIC)分别为2.5 mg/mL和0.625 mg/m...     

‘修水化红’甜橙成熟过程中黄酮含量与相关酶活性及抗氧化能力的关系

为明确‘修水化红’果实成熟过程中黄酮含量、相关酶活性与抗氧化能力的变化规律及它们之间的调控关系,以不同成熟期的‘修水化红’果实为研究对象,果皮与果肉分别对黄酮含量(总黄酮、橙皮苷)、相关酶活性[葡萄糖-6-磷酸脱氢酶(glucose-6-phosphate dehydrogenase,G6PDH)、苯丙氨酸解氨酶(phenylalnine ammonialyase,PAL)、肉桂酸-4-羟基化酶(cinnamic acid 4-hydroxylase,C 4H)、4-香豆酸-CoA-连接酶(4-coumarate coenzyme A ligase,4CL)、查尔酮异构酶(chalcone isomerase,CHI)]、抗氧化能力等进行测定与分析,研究其变化规律。‘修水化红’果皮的总黄酮与橙皮苷含量显著高于果肉。随着果实成熟度的增大,果皮和果肉的总黄酮、橙皮苷含量及5种相关酶活性均呈逐渐降低的趋势,且果皮与果肉的清除DPPH自由基、·OH、ABTS+·的能力与还原力也逐渐降低。果皮和果肉的总黄酮、橙皮苷含量与5种相关酶的活性呈极显著正相关,果皮总黄酮、橙皮苷含量分别与CHI活性、PAL活性之间的相关系数最高,果肉的总黄酮和橙皮苷含量均与CHI活性之间的相关系数最高,果皮与果肉的总黄酮、橙皮苷含量与4种抗氧化指标呈极显著正相关。G6PDH、PAL、C 4H、4CL、CHI等在‘修水化红’果实成熟过程中对于黄酮的积累有着重要的作用,CHI与PAL可能起最主要的作用,且总黄酮、橙皮苷是‘修水化红’果实主要的抗氧化成分。     

黑果腺肋花楸花色苷提取工艺优化及其抗氧化活性和组成鉴定

目的：优化超声波辅助提取黑果腺肋花楸花色苷的条件,测定花色苷的抗氧化能力,鉴定黑果腺肋花楸花色苷提取物的组成成分。方法：采用响应面法优化花色苷提取条件,通过1,1-二苯基-2-三硝基苯肼自由基清除能力、2,2’-联氨-双（3-乙基苯并噻唑啉-6-磺酸）二铵盐自由基清除能力及Fe3＋还原能力方法评价其抗氧化能力,高效液相色谱-质谱联用法进行成分分析。结果表明：提取温度60?℃、超声功率100?W、料液比1∶30（g/mL）、超声时间31?min、乙醇体积分数64%和pH?2.0时为最优提取条件,此时黑果腺肋花楸花色苷含量可达（3.61±0.01）mg/g。体外抗氧化实验表明,在相同质量浓度条件下,黑果腺肋花楸花色苷提取物的抗氧化活性明显高于VC。组分鉴定表明黑果腺肋花楸花色苷提取物中共有6?种花色苷,其中矢车菊-己糖苷二聚体和矢车菊-3,5-二己糖苷为新检测出的2?种花色苷。     

响应面法优化超临界CO2萃取苹果皮多酚的工艺及抗氧化性研究

对红富士苹果皮中的多酚进行超临界CO2提取,采用响应曲面法,对提取工艺进行了优化设计,建立了提取苹果多酚的二阶响应回归模型,得到了优化工艺条件为:压力35.06 MPa,温度53.04℃,时间2.62 h,提取率达到最大。苹果多酚有较好的抗氧化活性,对DPPH.和NO2-.的清除能力优于BHT。     

Polyphenols,ascorbic acid and antioxidant capacity of commercial nutritional drinks,fruit juices,smoothies and teas

Polyphenols of plant origin have received special interest in the last decade because of their potential health benefits. Consequently, many beverages with words ‘antioxidant’ and ‘polyphenols’ have been developed. However, many of the claims are misleading because some beverages so labelled have either no or minimal levels of polyphenols. The objectives of this study were to quantify polyphenols (TPC) and ascorbic acid contents and antioxidant capacity (AOC) of different beverages; identify major polyphenols in beverages that showed higher TPC; correlate the claim on the label with TPC and AOC; and determine the impact of consumer refrigerated storage on TPC and AOC of aronia, blackcurrant and pomegranate juices which contained the most TPC and AOC. Major polyphenols identified from these juices included anthocyanins, myricetin and epicatechin. TPC of aronia, blackcurrant and pomegranate juices was relatively stable during consumer refrigerated storage, even when the juice had been intermittently exposed to air.     

桑叶多酚的鉴定及其抗氧化、抗α-淀粉酶活性分析

目的:桑树叶片在传统医学中被用作降糖和降血压的药物,其作用机理与活性成分含量有关。评价桑叶提取物不同生物活性,包括生物活性物质含量、抗氧化活性和抗α-淀粉酶活性。方法:采用SPE（固相萃取技术）将多酚粗提液分离纯化为花色苷、非花色苷多酚和水层三个组分,采用HPLC-PDA和HPLC-ESI/MS2对桑叶中的多酚物质进行系统地定性和定量。利用DPPH（1,1-二苯基-2-三硝基苯肼自由基清除能力）、ABTS（2,2’-联氮-双（3-乙基苯并噻唑啉-6-磺酸））和FRAP（铁离子还原能力）三种方法测定不同提取物的抗氧化活性,并采用福林酚法、pH差异法和比色法测定桑叶提取物总酚、总花色苷和总原花青素含量。结果:桑叶中共鉴定出6种花色苷、42种非花色苷多酚,其中,矮牵牛素-3-葡萄糖苷和原花青素衍生物含量很高;桑叶中总酚、总花色苷和总原花青素的含量分别为14.09 mg GAE/g DW、0.17 mg C3G/g DW和17.24 μg PA2/g DW;多酚粗提液、花色苷、非花色苷多酚和水层对α-淀粉酶活性的IC₅₀（半抑制浓度）分别为8.31、13.70、0.25和12.00 mg/mL,由此看出非花色苷多酚的抗α-淀粉酶活性最高。结论:桑叶具有较强的抗氧化活性,其中花色苷显示出最高的抗氧化活性。这些数据可以为蒙古桑叶用作功能食品提供重要参考。     

不同品种桑椹酒抗氧化能力及其多酚含量分析

对6个不同品种的桑椹酒的总酚、总类黄酮、原花青素、总花色苷及桑椹酒中主要的两种花色苷（矢车菊-3-氧-芸香糖苷和矢车菊-3-氧-葡萄糖苷）的总抗氧化能力及其相关性进行了分析.结果表明,不同品种的总酚、总类黄酮、原花青素、总花色苷、矢车菊-3-氧-葡萄糖苷、矢车菊-3-氧-芸香糖苷和总抗氧化能力变幅和变异系数较大,存在显著差异（P＜0.05）;桑椹酒总抗氧化能力与总酚、总类黄酮、原花青素、总花色苷及矢车菊-3-氧-葡萄糖苷和矢车菊-3-氧-芸香糖苷含量之间存在正相关性,其中与总酚的相关性最强,达到0.917 2.     

刺葡萄皮醇提物和不同洗脱组分抗氧化成分及活性

以酸化甲醇为溶剂对刺葡萄皮进行超声波辅助提取,并用大孔树脂进行分离得到5 种不同洗脱组 分,研究刺葡萄皮醇提物和不同洗脱组分的活性成分及抗氧化能力。结果表明,刺葡萄皮含有较高含量的 多酚（1.836 mg/g mf）、黄酮（0.874 mg/ g mf）、VC（3.567 mg/g mf）、丹宁（3.578 mg/g mf）和花青素 （2.970 mg/g mf）,其1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基清除能力、 2,2’-二氮-双（3-乙基苯并噻唑-6-磺酸）二铵盐自由基（2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) radical, ABTS＋·）清除能力、铁离子还原能力（ferric reducing antioxidant power,FRAP）分别为22.325、17.595、 26.487 μmol TE/g mf。在5 种组分中以水解吸组分活性成分含量最高,其多酚、黄酮、VC、丹宁和花青素含量分别 为0.876、0.116、1.577、1.576 mg/g mf和1.330 mg/g mf,其DPPH自由基、ABTS＋·清除能力和FRAP分别为3.636、10.109、 13.415 μmol TE/g mf,相关性分析表明抗氧化活性与活性成分花青素、丹宁、VC含量呈强相关关系,表明抗氧化活性可 能主要由这3 种活性物质贡献。本研究结果表明,刺葡萄皮有潜力作为膳食补充抗氧化物质的主要来源。