Phytochemical characterisation for industrial use of pomegranate (Punica granatum L.) cultivars grown in Spain

BACKGROUND: The study of 15 pomegranate cultivars was carried out in order to demonstrate the wide diversity among the quality of Spanish pomegranates, and compared to ‘Wonderful’ cultivars, which are used worldwide for industrial purposes. Juice yield, quality parameters, organic acids and sugars, colour, vitamin C, ellagic acid, punicalagins, anthocyanins, total phenolic content, antioxidant capacity, and sensory properties were measured. RESULTS: A considerable variation was found between ‘Wonderful’ and pomegranates of Spanish origin, according to both cluster analysis and principal component analysis. ‘Wonderful’ juices displayed large antioxidant activity and a polyphenol content with very high acidity. In contrast, ‘Mollar de Elche’ showed fewer anthocyanins although it had very superior organoleptical properties. In addition to a high content in ellagitannins, ‘Valenciana’ juices had exclusive colour parameters. CONCLUSION: These useful results can be employed by the juice processing industry to select those properties more interesting for the development of pomegranate juices that are organoleptically attractive and rich in bioactive compounds. Copyright © 2011 Society of Chemical Industry     

石榴抗糖尿病生物活性的研究进展

体外和体内实验均证实石榴汁、石榴皮、石榴花、石榴籽和石榴叶等具有抗糖尿病的功效,综述了石榴多个部位的降血糖效果、降血糖活性成分及其作用机制的研究进展。石榴中的多酚类是抗糖尿病的主要活性物质,主要通过提高胰岛素受体敏感性、增强PPAR-γ（Peroxisome proliferator-activated receptor,过氧化酶体增殖物激活受体）的表达、抑制α-葡萄糖苷酶活性等作用达到抗糖尿病的功效,为石榴的进一步开发利用提供参考。      

石榴叶酚酸测定及提取工艺研究

以石榴叶为原料,采用Folin-Ciocalteu 法定量测定石榴叶提取液中总酚含量,通过单因素试验和正交试验对石榴叶总酚的提取工艺进行探讨。确定其最佳提取条件为：料液比1:25(g/ml),温度70℃,提取溶剂为75% 乙醇,提取时间1.5h。综合考虑成本因素,原料过1mm 筛较为适宜,按照该工艺提取石榴叶总酚的得率为16.63%。     

Pomegranate (Punica granatum) juices: chemical composition, micronutrient cations, and antioxidant capacity

Abstract: Phenolics, flavonoids, anthocyanins, and tannins of pomegranate juices, obtained from 9 Tunisian ecotypes were quantified. Phenolics and flavonoids in the variety Tounsi (TN) (3299 mg gallic acid equivalents [GAE]/L and 636 mg quercetin equivalents [QE]/L of juice, respectively) were higher than in the variety Gabsi (GB) (1570 mg GAE/L and 135 mg QE/L of juice, respectively). The highest anthocyanins quantity was found in GB 2 with 156 mg cyanidin‐3‐glucoside equivalents (CGE)/L. TN 3 ecotype showed the highest tannins quantity with 2550 mg catechin equivalents (CE)/L of juice. TN 1 presented the highest radical‐scavenging activity (2, 2′‐azinobis‐3‐ethylbenzothiazoline‐6‐sulphonate [ABTS], IC₅₀ [50% inhibition concentration] = 525 mg/L), as well as the highest concentration of micronutrient cations (potassium and sodium). A high correlation (R²= 0.80) between antioxidant capacity and proanthocyanin contents was found, this suggests that proanthocyanins are the principal contributor in the antioxidant capacity of pomegranate. Our data suggest also that the high concentrations of K⁺ and Na⁺ may play a role in the adaptation of pomegranate to arid environments.     

利用超临界技术萃取石榴叶总酚工艺研究

利用超临界CO2 装置对石榴叶中总酚提取工艺进行研究,以期得到高生理活性和高纯度的石榴叶活性物质。通过单因素和正交试验,得到最佳萃取条件为料液比1:2.5(g/ml)、萃取压力25MPa、萃取温度60℃、萃取时间120min。活性物质得率为0.1728%,纯度为42.61%。     

响应面优化超声-微波协同提取石榴叶中总黄酮工艺的研究

为确定石榴叶中总黄酮提取的最佳工艺,在单因素试验的基础上,应用响应面法优化石榴叶中总黄酮的提取条件。结果表明:微波功率、提取时间和料液比对黄酮提取率影响极显著;最佳工艺为:乙醇体积分数71.5%(v/v),微波功率662 W,提取时间262 s,液料质量体积比33.5g/m L,在此条件下提取1次,石榴叶中总黄酮的提取率为89.21%。     

石榴皮总黄酮的提取工艺及抑制亚硝化反应

目的:研究石榴皮总黄酮的提取工艺及黄酮类物质对亚硝化反应的抑制能力。方法:通过正交试验,探讨影响总黄酮提取率的因素范围和最佳组合,并采用分光光度法测定总黄酮提取液对亚硝酸盐清除能力和亚硝胺抑制能力。结果:石榴皮总黄酮的最佳提取工艺条件为乙醇体积分数60%、料液比1:60(g/mL)、提取时间40min、超声电流强度150mA。在最佳提取工艺条件下,石榴皮总黄酮的平均提取率为84.8mg/g,石榴皮总黄酮提取液对亚硝酸钠的最大清除率为81.2%,对亚硝胺合成的最大阻断率为67.0%。结论:石榴皮总黄酮提取液对亚硝化反应的抑制能力较强。     

Evolution of juice anthocyanins during ripening of new selected pomegranate (Punica granatum) clones

 For five new clones of pomegranate, cultivated under homogeneous conditions, changes in juice anthocyanin contents during ripening were studied. Six anthocyanin pigments were found to be responsible for the red color of pomegranate juice. These were quantitatively and qualitatively analyzed by high-performance liquid chromatography and identified as delphinidin 3-glucoside and 3,5-diglucoside, cyanidin 3-glucoside and 3,5-diglucoside and pelargonidin 3-glucoside and 3,5-diglucoside. Generally, there was an increase in juice pigmentation during fruit ripening. In the early fruit-ripening stages, delphinidin 3,5-diglucoside was the main pigment, followed by cyanidin 3,5-diglucoside, while in the later stages, the monoglucoside derivatives cyanidin 3-glucoside and delphinidin 3-glucoside increased considerably. The pelargonidin derivatives were always present in small amounts. Received: 1 March 1999     

Antioxidant capacity changes of 3 cultivar Chinese pomegranate (Punica granatum L.) juices and corresponding wines

This study investigated the antioxidant capacities that included Ferric reducing antioxidant power (FRAP), 1, 1-diphenyl-2-picryl hydrazine (DPPH), ·OH and O(2·)(-)-scavenging abilities, total polyphenols (TP) and total anthocyanins (TA) in pomegranate (Punica granatum L.) juice (PJ) and pomegranate wine (PW). The correlations among them were also analyzed. Both PJ and PW showed significantly high TP and antioxidant capacities, but some differences existed among these cultivars. There was 1596.67 mg/L TP found in sweet PJ, while sour PJ showed the highest titratable acidity of 35.90 g/L and lowest pH value at 2.56. Red PJ was found to have the highest TA (82.26 mg/L) in the 3 cultivars. Sweet PJ showed higher DPPH-scavenging ability and higher FRAP than others. Both PJ and PW exhibited high and relatively stable ·OH-scavenging abilities, in which sour PJ and sour PW had higher O(2·)(-) scavenging capacity than others. Significant positive correlations were observed among TP, DPPH, and FRAP in both PJ and PW. A high correlation between antioxidant capacities and TP indicated that phenolic compounds were major contributors to the high antioxidant activity of PJ and PW.     

Total lipid content and fatty acid composition of oilseed from lesser known sweet pomegranate clones

The oil content and fatty acid composition of the oilseed of seven lesser known Spanish sweet pomegranate (Punica granatum L) clones were determined by gas chromatography. The seeds contained oil in the range of about 63–122 g kg⁻¹ dry matter, a notably lower content than that of some oriental pomegranate cultivars. Levels of lipid content probably could be considered insufficient for economic industrial exploitation compared with those of conventional oilseeds. The predominant fatty acid was the polyunsaturate (n − 3) linolenic acid (43.4–88.2%), followed by the diunsaturate linoleic (5.3–16.5%), the monounsaturate oleic (3.7–20.3%) and palmitoleic (traces to 2.9%) acids. To a lesser extent the saturates palmitic (2.6–14.9%) and stearic (1.2–9.0%) acids were also found in all clones. Lauric and arachidic acids were rarely detected. We have not confirmed the presence of behenic (C22:0) and lignoceric (C24:0) acids previously reported in edible and non‐edible pomegranate cultivars. Intervarietal differences in fatty acid composition were shown and they could be useful to establish chemotaxonomic differences. In contrast with previous reports on sweet pomegranate cultivars, a very low (0.04–0.35) saturated/unsaturated fatty acid ratio was found. © 2000 Society of Chemical Industry     

Heavy Metals Bounding Ability of Pomegranate (Punica granatum) Peel in Model System

Pomegranate fruit is an important sources of natural phenolic compounds. In this study, the influence of pomegranate fruit peel on binding of some heavy metals were established by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). Also, the total phenolic content of methanol extract of pomegranate fruit peel was determined with the Folin-Ciocalteu method. Amounts of 1, 2, 3, 10, 20, 40, and 60 g of ground peel were used in this experiment. After pomegranate samples were weighed, they were added into 500 ml baker. Each sample was treated by several solutions contained the heavy metal elements at different concentrations. The heavy metal contents in the solutions prepared with ground material were decreased with increasing of ground material. At the same time, the bounding rate of heavy metals increased with the increase of ground peel amounts. Lead (Pb) with 99.2% rate for solution obtained from 20 g ground sample was the highest bound element. It can be observed from these results that the amount of metal ions bound by the ground material differed from on fraction to others.     

Anthocyanins characterization of 15 Iranian pomegranate (Punica granatum L.) varieties and their variation after cold storage and pasteurization

Anthocyanins (ACs) are phenolic compounds that are distributed widely in fruits and vegetables. Apart from imparting color to plants, ACs also have an array of health-promoting benefits. In this research, the amounts of major ACs of 15 pomegranate (Punica granatum L.) varieties obtained from Yazd province were determined. The major ACs detected in the studied varieties were as follows: delphinidin 3-glucoside (2.19–16.29 mg/L), delphinidin 3,5-diglucoside (2.36–63.07 mg/L), pelargonidin 3-glucoside (0.26–1.36 mg/L), pelargonidin 3,5-diglucoside (0.01–8.11 mg/L), cyanidin 3-glucoside (5.78–30.38 mg/L), and cyanidin 3,5-diglucoside (4.39–166.32 mg/L). The effect of storage time of unprocessed and pasteurized juices on ACs content of four selected varieties was also studied. Average degradation percentage of each AC was between 23.0 and 83.0% during 10 days at 4 °C. Moreover, in pasteurized juices average degradation of ACs was 42.8 ± 0.5% after 10 weeks storage at 4 °C.     

Volatile organic compounds in the aril juices and seeds from selected five pomegranate (Punica granatum L.) cultivars

A study was conducted to investigate the distribution of volatile organic compounds in the juice and seed of the most popular five pomegranate cultivars (“Ek?i,” “Devedi?i,” “Hicaz,” “Kat?rba??,” and “Keben”) in Turkey. The volatile organic compounds were analyzed using solid phase micro-extraction and gas chromatography–mass spectrometry. A total of 60 volatile organic compounds, belonging to six chemical groups including aldehydes, alcohols, esters, terpenes, ketones, acids, and phenol were identified. There were 11 volatile organic compounds (1-hexanol, [Z]-3-hexen-1-ol, 1-octanol, α-terpineol, β-myrcene, limonene, [E]-α-bergamotene, β-caryophyllene, hexanal, [E]-2-hexenal, and guaiacol) common to all five pomegranate juices and seeds. Hexalin, phenylacetaldehyde, 3-methyl butanal, and methyl-(1-methylethenyl) benzene were found in seeds only. According to discriminant analysis based on Eigenvalues, volatile organic compounds recovered in the juices could be used to discriminate and classify the pomegranate cultivars. “Devedi?i” and “Hicaz” were the most promising cultivars with respect to the largest volatile organic compounds, high total soluble solid and deep red color.     

Encapsulation of polyphenols and anthocyanins from pomegranate (Punica granatum) by spray drying

Pomegranate (Punica granatum) bioactive compounds (polyphenols and anthocyanins) of juice (PJ) and ethanolic extracts (PE) were encapsulated with maltodextrin (MD) or soybean protein isolates (SPI) by spray drying using a 2² statistical factorial design for each systems studied (PJ–MD, PJ–SPI, PE–MD and PE–SPI) considering the proportion of coating material and the inlet temperature as independent variables. The stability of the bioactive compounds microcapsules powders obtained under optimal conditions for each system was studied at 60 °C in oven for 56 days. The polyphenols encapsulating efficiency was significantly better in SPI matrix whereas for anthocyanins was in MD matrix. By the other hand, during the storage, the MD microcapsules provided a significant greater protective effect on the polyphenols and anthocyanins than SPI, as was shown by the lower degradation rate constants. When the microcapsules were added to yogurt the stability of the bioactive compounds followed a similar behaviour to those without encapsulation, except for PE–MD.     

Hot water,UV‐C and superatmospheric oxygen packaging as hurdle techniques for maintaining overall quality of fresh‐cut pomegranate arils

BACKGROUND: In recent years there has been increasing consumer pressure to avoid the use of agrochemicals such as chlorine on fresh plant products for extending their shelf life. The combined use of eco‐sustainable techniques may be an alternative. The effect of hot water (HW), ultraviolet‐C (UV‐C) light and high oxygen packaging (HO) on the overall quality of fresh‐cut pomegranate arils stored under modified atmosphere packaging (MAP) for up to 14 days at 5 °C was studied. RESULTS: Arils extracted manually, washed with chlorine (100 µL L^?1 NaClO, pH 6.5, 5 °C water), rinsed and drained were exposed to single or combined (double and triple) hurdle techniques. The HW treatment consisted of a 30 s immersion in water at 55 °C followed by air surface drying. A 4.54 kJ m^?2 dose was used for the UV‐C treatment before packaging. Active MAP with initial 90 kPa O₂ was used in the HO treatment. The respiration rate remained relatively constant throughout shelf life, with no differences among treatments. CO₂ accumulation was higher within HO packages. HW induced a slight reduction in total soluble solids, while no changes in titratable acidity were found. HO‐treated arils had the highest phenolic content, while the lowest was found in HW‐treated arils. The lowest antioxidant activity was found in HW + UV‐C + HO and the highest in UV‐C + HO and HO treatments. HW alone or in combination with UV‐C and HO inhibited mesophile, mould and yeast growth, while UV‐C + HO was most effective for controlling yeast and mould growth. CONCLUSION: UV‐C and HO either alone or in combination are promising techniques to preserve the quality of pomegranate arils for up to 14 days at 5 °C. © 2012 Society of Chemical Industry     

响应面法优化石榴叶总酚的亚临界水提取工艺

本研究采用亚临界水萃取法提取石榴叶总酚,并通过响应面法优化其提取工艺参数。在单因素实验的基础上,根据响应面Box-Behnken实验设计原理,采用三因素三水平的分析法,选取提取温度、提取时间、液料比为自变量,考察其对石榴叶提取物中总酚含量的影响,并通过方差分析优化其工艺。结果表明,回归方程对实验拟合较好,可以对石榴叶中总酚含量进行很好的分析和预测;优化后的最佳工艺条件为:提取温度134℃、提取时间31 min、液料比52∶1 m L/g。在该条件下,石榴叶总酚含量为169.24 mg GAE/g,与预测值173.31 mg GAE/g基本一致。通过与溶剂加热回流法相比较,亚临界水提取可明显提高石榴叶总酚的含量,并缩短提取时间。      

新疆石榴皮总多酚有效部位的抗氧化、抗菌及抗肿瘤活性

目的:研究和评价新疆石榴皮总多酚粗提物和有效部位在体外的生物活性。方法:采用DPPH法、平皿二倍稀释法和MTT法分别对总多酚粗提物和有效部位进行抗氧化活性、抗菌和体外抗肿瘤活性测定。结果:石榴皮总多酚提取物清除DPPH自由基的效果显著,并且有效部位清除能力优于粗提物;石榴皮总多酚有效部位对临床常见致病菌有明显的抑制作用,具有广谱性,并且对一些临床耐药性的致病菌也有抑制作用;同粗提物相比,总多酚有效部位有较好的抗肿瘤活性。结论:石榴皮中的总多酚有效部位具有较好的抗氧化、抗菌及抗肿瘤活性。     

基于F-AAS、GF-AAS对云南石榴蜂蜜中矿质元素进入途径研究

石榴蜂蜜为云南蒙自地区的特色蜂蜜。本文利用火焰原子吸收光谱仪(F-AAS)、石墨炉原子吸收光谱仪(GF-AAS)测定石榴蜂蜜、石榴植株各器官(根、茎、叶和花)及生境的土壤和水中9种矿质元素(K、Na、Pb、Cd、Zn、Mn、Mg、As和Cu)的含量。表明:石榴蜂蜜中K元素含量最高(283.68 mg/kg),Cd元素含量最低(0.008 mg/kg)。聚类分析和雷达图均显示石榴花对石榴蜂蜜中矿质元素含量的影响最大,其中K元素从花中进入到石榴蜂蜜的比例最大(37.79%);Cd元素的比例最少(0.46%)。相关性分析表明,石榴蜂蜜中的各矿质元素与植株各器官、水均有不同程度的显著相关,其中花中的K、Na、Zn、Mn和Mg,根中的Pb、Cd和As,水中的Na、Mn和As,茎中Pb和Mn,叶中的Zn元素均与石榴蜂蜜呈显著相关。本研究表明,石榴蜂蜜中的矿质元素除直接来源于"土壤-植株-花蜜"这个生物链外,还与环境和人类活动等因素有关。     

石榴叶多酚对急性酒精性肝损伤小鼠肾脏、心脏及免疫器官的抗氧化作用

目的:研究石榴叶多酚(purified polyphenols from Punica granatum L.leaves,PPPL)对酒精所致急性肝损伤小鼠肾脏、心脏、脾脏、胸腺的保护作用。方法:将66只雄性小鼠随机分为空白对照组、模型对照组、阳性对照组(联苯双酯150 mg/(kg·d)),PPPL低、中、高剂量组(100、200、400 mg/(kg·d)),连续灌胃30 d,第31天除空白对照组外其余各组给予50%乙醇(12 m L/kg),建立小鼠急性肝损伤模型。将小鼠脱臼处死后取肾脏、心脏、脾脏及胸腺,测定其超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活力及丙二醛(malondialdehyde,MDA)、还原型谷胱甘肽(glutathione,GSH)含量。结果:与模型对照组相比,PPPL各剂量组均能提高小鼠各脏器的SOD、CAT、GSH-Px活性和GSH含量,降低MDA含量。结论:PPPL对酒精性肝损伤小鼠肾脏、心脏及免疫器官具有明显的抗氧化作用。