Study on the Mechanism of Browning of Pomegranate (Punica granatum L.cv.Ganesh) Peel in Different Storage Conditions

Peel browning of pomegranate fruit is the key problem during storage. The mechanism of it during storage in relation to the technology of the browning control was studied in this paper. The effects of storage temperature, gas component and pH value on peel browning of sweet pomegranate fruit in Lintong, Shaanxi Province, China, were investigated. Change in tannin content was measured and the relationship between the activities of ascorbic acid oxidase （AAO）, polypenoloxidase （PPO）, peroxidase （POD）, catalase （CAT） and peel browning was analysed. The results showed tannin was the basic substance of pomegranate peel browning. The activities of the browning index of peel were correlated positively with AAO, PPO and POD, correlated negatively with CAT activity. Application of intermittent warming for 24 h at （15 ± 0.5）℃ every 5 days for pomegranate fruit storage under the conditions of pH 4.0, （5.0± 0.5）℃ and 5.0% CO2 ＋ 8.0% O2 ＋ 87.0% N2 gas component could delay browning, with the browning index being 0.15 after 120 days of storage. Enzymatic tannin denaturation was the main cause that led to peel browning of pomegranate fruit during storage. The browning control of pomegranate fruit peel was effective using intermittent warming storage with suitable pH, temperature and gas component.

Comprehensive evaluation of 20 pomegranate(Punica granatum L.) cultivars in China

Recent investigations on pomegranate products have significantly increased and successfully drawn consumers’ attention to nutritional and medicinal values, promoting the pomegranate industry’s development worldwide. However, little information on pomegranates grown in China is available. Morphological and chemical characterizations of fruits and arils from 20 pomegranate cultivars in six regions of China were investigated. Combined with overall scores by principal component analysis, ‘Yushiliu No. 1’, ‘Taishanhong No. 2’, ‘Tunisia’ and ‘Mollar’ were promising cultivars, and Chinese researchers bred the first two. It was surprising that ‘Mollar’ had bigger fruit size and more aril moisture grown in China than in Spain. Cultivars with higher anthocyanin content in arils were ‘Turkey’, ‘Moyu’ and ‘Red Angel’, which might be used as the source of natural red food colourants. While red husk ‘Hongruyi’ and ‘Hongshuangxi’ with higher vitamin C, aril moisture and lower titratable acid in arils, might also be promising cultivars for further various utilization. Furthermore, the comparison of ‘Tunisia’ fruits from four regions revealed that cultivation locations had more influence on fruit traits than genotypes. Maturity index classification was established for Chinese pomegranate cultivars. Therefore, the results would provide a valuable guide for agricultural cultivation, industrial utilization, and breeding.

Ameliorative properties of Iranian Trigonella foenum-graecum L. seeds and Punica granatum L. peel extracts in streptozotocin-induced experimental diabetic guinea pigs

Objective: To assess the ameliorative properties of Iranian Trigonella foenum-graecum L.(T. foenum-graecum) seeds and Punica granatum L.(P. granatum) peel extracts against streptozotocin-induced diabetes in male guinea pigs.Methods: Sixty guinea pigs were divided into six groups(10 guinea pigs per group).Group 1 consisted of normal animals. Groups 2 and 3 were treated with Iranian T. foenum-graecum seeds and P. granatum peel extract alone, respectively. Group 4 was treated with streptozotocin only; whereas Groups 5 and 6 receiving streptozotocin were treated with Iranian T. foenum-graecum seeds and P. granatum peel extract, respectively.All animals were treated for 30 days, and the body weight, blood and liver biochemical parameters were measured.Results: Guinea pigs exposed to streptozotocin showed an alteration in body weight gain, fasting glucose level, kidney function parameters(blood urea nitrogen and creatinine) as well as decreased serum and hepatic total protein level. In addition, it increased the cholesterol and triglyceride level, while decreasing the hepatic glucose-6 phosphate dehydrogenase activity, glycogen, glutathione content and hepatic catalase activity. Oral treatment with T. foenum-graecum seeds and P. granatum peel extracts revealed significant protective properties with respect to body weight gain and other biochemical parameters studied.Conclusions: The Iranian T. foenum-graecum seeds and P. granatum peel extracts are significantly potent in ameliorating diabetic condition induced by streptozotocin and improving various biochemical parameters in serum and liver of guinea pigs.

Effect of Punica granatum peel extract on learning and memory in rats

Objective:To evaluate potential memory enhancing effect of Punica granatum peel extract on rats.Methods:Healthy adult male albino rats of Wistar strain were used.Each group of 6 rats were administered either distilled water or 50 mg/kg of extract or 100 mg/kg of extract for 15 days and subjected to passive avoidance test or T-maze test.In the next phase rats were administered distilled water or 100 mg/kg of extract for 15 days and the rats were given injection diazepam before subjecting them to the tests.Results:The overall performance was better in test groups compared to control groups.Among the test groups,100 mg/kg rats performed better than 50 mg/kg.The effect on spatial learning parameters like mean number of alternations and mean percentage bias was more marked compared to retention testing parameters like latency. 100 mg/kg Punica extract treated group also improved performance of diazepam treated rats. Conclusions:There is a definite trend of memory improvement by Punica granatum peel with effects being more marked on spatial learning tendency and long term memory than on retention capacity.

Antioxidant Activity of Pomegranate (<i>Punica granatum</i>L.) Fruit Peels

The antioxidant activity of pomegranate fruit peels was evaluated using in vitro tests. 80% methanolic extracts (ME) of peels had higher yield (45.4%) and total phenolics (27.4%) than water (WE) or ether extracts (EE). The reducing power of ME was more potent (P α-catechin. Pomegranate peels contained phenolics, exhibited DPPH scavenging activity and reducing power.

Removal of Fluoride from Groundwater by Carbonised <i>Punica granatum</i>Carbon (“CPGC”) Bio-Adsorbent

This study applies the development and application of low cost, Punica granatum bio-adsorbent for the removal of fluoride in groundwater. The batch adsorption study was carried out to analyze the defluoridation by contact time variation, adsorbent dose, adsorbate concentration, adsorbent particle size and presence of co-anions at neutral pH. The analysis of the isotherm equilibrium data using the Langmuir and Freundlich equations by linear methods showed that the data fitted better with Freundlich model (R2 > 0.980). Prepared adsorbent showed enhanced removal of fluoride concentration by 78.1% at equilibrium contact time of 75 minutes. Carbonised Punica granatum Carbon (CPGC) seeds showed a high affinity for fluoride ions compared with other conventional adsorbents. Therefore, it can be considered as a potentially “good”, low-cost bio-adsorbent for de-fluoridation of water compared to other bio-adsorbent.

Antinociceptive Effects of Pomegranate (<i>Punica granatum</i>L.) Juice and Seed Extracts on Acute Corneal Pain in Mice

In the present study, the antinociceptive effects of acute (2, 4 and 6 ml/kg) and chronic (1, 2 and 3 ml/kg for 14 days)oral administration of?pomegranate (Punica granatum?L.) juice and seed?extract with or without morphine and naloxane were investigated?on?hypertonic saline-induced acute corneal pain perception in mice. The number of eye wipes with a forelimb was counted for a period of 30 seconds as the criterion for pain assessment. Acute oral administration of the extract?(at 6 ml/kg dose, once) and chronic oral administration?(at 2 and 3 ml/kg for 14 days each) significantly decreased the number of eye wipes after subcutaneous injection of morphine (2 mg/kg, sc), naloxone (2 mg/kg, sc) and normal saline (2 mg/kg, sc) compared with control (p < 0.05). The morphine-induced antinociception was significantly improved by both acute and chronic oral administrations of pomegranate extract (p < 0.05). Naloxone (2 mg/kg, sc) did not reverse the antinociceptive effects of acute (at 6 ml/kg dose, once, oral) and chronic (at 2 and 3 ml/kg for 14 days each) treatments. These findings demonstrate that acute high-dose and long-term lower-dose of pomegranate juice and seed extract can decrease acute corneal pain and improve morphine-induced antinociception in mice.

Phytochemical Determination and Antibacterial Activity of Punica granatum Peel Extracts against Plant Pathogenic Bacteria

Plant pathogenic bacteria are recognized to be harmful microbes able to decrease the quantity and quality of crop production in the world. Punica granatum peel was screened for its potential use as biological control agent for plant pathogenic bacteria. P. granatum peel was successfully extract using n-hexane, methanol and ethyl acetate by maceration. The highest yield obtained by ethyl acetate showed that ethyl acetate extracted more compounds that readily soluble to methanol and n-hexane. For in-vitro antibacterial activity, three different species of plant pathogenic bacteria were used namely Erwinia carotovorum subsp. Carotovorum, Ralstonia solanacearum, and Xanthomonas gardneri. For all crude extracts, four different concentrations 25, 50, 100 and 200 mg/ml were used in cup-plate agar diffusion method. Streptomycin sulfate at concentration 30 μg/ml was used as positive control while each respective solvent used for peel extraction was used as negative control. The results obtained from in vitro studies showed only ethyl acetate extract possessed antibacterial activity tested on the plant pathogenic bacteria. Methanol and n-hexane did not show any antibacterial activity against plant pathogenic bacteria selected where no inhibition zones were recorded. R. solanacearum recorded the highest diameter of inhibition zones for all range of concentrations introduced followed by E. carotovorum subsp. Carotovorum and X. gardneri. For the minimum inhbitory concentration (MIC) and minimum bactericidal concentration (MBC), only the ethyl acetate extract was subjected to the assay as only ethyl acetate extract exhibited antibacterial activity. The minimum concentration of ethyl acetate extract that was able to inhibit plant pathogenic bacteria was recorded at a concentration of 3.12 mg/ml which inhibited R. solancearum and E. carotovorum subsp. Carotovorum, followed by X. gardneri at concentration 6.25 mg/ml. For the minimum bactericidal concentration (MBC), the results showed that at the concentration of 12.5 mg/ml, the extract was still capable of killing the pathogenic bacteria, R. solanacearum, and P. caratovora sub.sp. caratovora while for the bacteria X. gardneri, the concentration that was able to kill the bacteria was 25 mg/ml. The qualitative estimation of phytochemical constituents within P. granatum L. ethyl acetate peel extracts had revealed the presence of tannins, flavonoids, phenols alkaloid, Saponins, and terpenoids. This study has demonstrated that Ethyl Acetate peel extracts of P. granatum has significant antibacterial activity against pathogenic plant bacterial, and it could be of high agricultural value.

石榴蔗糖代谢相关酶SPS和INV基因家族鉴定与表达分析

蔗糖磷酸合成酶(SPS)和蔗糖转化酶(INV)是蔗糖代谢的关键调控酶,在植物生长发育过程中起重要作用。本研究利用生物信息学和荧光定量PCR等分子手段,鉴定石榴SPS和INV基因家族成员,分析其理化性质、保守结构域、保守基序、二级结构、亚细胞定位、系统进化关系和表达模式。结果表明,从石榴基因组中鉴定出4个SPS基因和11个INV基因,其编码蛋白均为不稳定蛋白,具有典型的保守结构域,家族成员间特征motif数量和种类大致相同,蛋白结构高度保守;这些蛋白不均匀地分布在染色体上,均定位于叶绿体中,二级结构主要由α-螺旋和无规则卷曲组成。石榴SPS和INV基因家族成员间存在不同程度的亲缘关系,与巨桉同源性较高;不同SPS和INV基因在石榴果实不同发育时期的表达模式存在差异,PgINV3在9月15日(果实增大期)表达水平最高,显著高于其他时期。本研究结果对解析石榴果实中蔗糖代谢的分子机理具有重要意义。

Plackett-Burman和Central Composite Design试验设计法优化石榴皮中熊果酸的SFE-CO_2萃取工艺

目的:探讨应用SFE-CO2萃取石榴皮中熊果酸的最佳工艺。方法:以熊果酸得率为考察指标,通过Plackett-Burman(PB)试验设计筛选影响熊果酸得率的显著性因素,最陡爬坡试验逼近熊果酸得率最大区域,Central Composite Design(CCD)试验设计对显著性因素进行响应面优化得到影响熊果酸得率的二阶数学模型,进而得出最佳工艺条件。结果:SFE-CO2萃取石榴皮中熊果酸的最佳工艺条件为:萃取温度46.29℃,萃取时间91.6 min,萃取压力34.49 MPa,在此条件下,验证试验测得熊果酸得率为12.508 mg/g,与模型预测值12.645 mg/g接近。结论:将PB试验和CCD试验设计联合应用于优化石榴皮中熊果酸SFE-CO2萃取工艺,筛选结果具有统计学意义,工艺操作具有可行性。

Folin-Ciocalteu比色法测定石榴不同部位总多酚的含量

石榴含有丰富的多酚类化合物(含量因部位不同而有差异),这类化合物具有抗动脉硬化、降低胆固醇、抗氧化和抗辐射等作用,可用来评价石榴的活性。本文采用Folin-Ciocalteu法对石榴中的总多酚进行检测。以没食子酸为对照品,校准曲线的回归方程为y=0.04659+109.89x(r=0.9994);对稳定性、精密度、重现性、回收率进行了试验,该方法简便、快速、准确,是检测石榴中总多酚的可靠方法。

山东石榴品种遗传多样性与亲缘关系的荧光AFLP分析

利用荧光AFLP标记技术,采用8对EcoR I/Mse I引物对山东省25个石榴品种进行AFLP-PCR分析,结果表明:25个石榴品种扩增的多态性位点数从70条到126条不等,平均90.25条,平均多态性位点41.78%;所有检出位点的平均观测等位基因数、平均有效等位基因数、平均Nei's基因多样度和平均香农信息指数分别为1.4178、1.1874、0.1133和0.1752;方差分析显示各位点的Nei's基因多样度和香农信息指数具有不同程度的显著性差异;基于Lei&Li相似系数利用UPGMA法进行聚类分析,在相似系数0.786处将25个品种划分为4大类。根据AFLP结果探讨了山东石榴品种的亲缘关系与新品种选育的前景。

不同产地维药古丽娜HPLC指纹图谱研究

目的:建立不同产地古丽娜的HPLC指纹图谱,考察不同产地古丽娜药材的质量。方法:采用Venusil XBP C18色谱柱(250 mm×4.6 mm,5μm);流动相为乙腈(A)-0.4%磷酸溶液(B),梯度洗脱,流速为1.0 mL/min;柱温:25℃;检测波长:280 nm;进样量10μL。结果:确定由12个共有峰构成古丽娜药材的指纹特征,精密度和重复性中共有峰相对保留时间和相对峰面积RSD均小于3.0%,12批样品与生成的对照指纹图谱的相似度均大于0.85。对12批药材进行聚类分析,分成3类,聚类分析显示产地和采集时间与药材的质量相关。结论:该方法精密度高、重现性好,可为古丽娜药材的质量评价提供参考,也为古丽娜药材进一步开发利用奠定基础。

川滇石榴品种遗传多样性及亲缘关系的AFLP分析

石榴（Punica granatum）为石榴科（Punicaceae）石榴属（Punica）落叶灌木或小乔木,原产伊朗、阿富汗等中亚一带,从西汉张骞出使西域将涂林安石榴引入我国,石榴作为水果和观赏树木在我国已有2000多年的栽培历史。经长期天然杂交和基因突变,以及采用实生、分株、嫁接等多种繁殖方法,产生了复杂而多样的品种和类型,据不完全统计,我国现有石榴品种资源200多个,遍及南北各地20多个省区,形成了山东枣庄。

石榴花多酚对糖尿病大鼠IL-6、TXB2及PPAR-γ mRNA基因表达的影响

目的观察石榴花多酚对小剂量链脲佐菌素加高脂饲料诱导的胰岛素抵抗模型大鼠IL-6、TXB2以及心肌组织PPAR-γ mRNA基因表达的影响。方法♂SD大鼠高脂饲料喂养1mon后注射小剂量STZ,2wk后测大鼠空腹血糖,血糖值>11.1者为造模成功的大鼠,将造模成功的大鼠随机分为模型组和药物干预组,另设空白对照组,药物干预1mon,常规测定各组大鼠给药前后的空腹血糖(FPG)和给药后各组大鼠的空腹血清胰岛素水平(Fins)、IL-6、TXB2,计算胰岛素敏感性指数(ISI)、胰岛素抵抗指数(Homa-IRI),提取心肌组织总RNA,采用逆转录PCR技术扩增PPAR-γ基因片段,检测其基因表达水平。结果石榴花多酚能降低模型大鼠FPG水平和Fins、IL-6、TXB2含量,增加PPAR-γmRNA基因表达,提高ISI,降低Homa-IRI。结论石榴花多酚对大鼠IR有一定程度的改善作用,其机制可能与提高IR大鼠心肌组织PPAR-γ基因的表达有关。

HPLC法测定新疆不同产地石榴皮中没食子酸的含量

目的:测定新疆石榴皮中没食子酸的含量。方法:用高效液相色谱法,ZORBAX SB-C_(18)(4.6 mm×250 mm,5μm)色谱柱,流动相为甲醇-0.2%磷酸(3:97),检测波长为273 nm。结果:没食子酸在2.72～348.56μg/ml范围内呈线性关系,Y=31 664X+18 333,r=0.999 8(n=8);平均加样回收率为100.60%,RSD=1.37%(n=6)。结论:该方法精密可靠,可作为石榴皮药材质量控制的方法。

RP-HPLC法测定石榴不同部位中熊果酸和齐墩果酸的含量

采用超声技术提取石榴不同部位中熊果酸和齐墩果酸,建立RP-HPLC法测定其含量。色谱柱为KromasilC18柱（250mm×4.6mm,5μm）,流动相为甲醇-0.2%磷酸水溶液（87∶13）,光电二极管阵列检测器,检测波长210nm,流速0.8mL/min,柱温28℃。熊果酸进样量在0.443-7.088μg,齐墩果酸进样量在0.247-3.952μg时呈现良好的线性关系,相关系数均为0.9999,平均加样回收率分别为98.53%和98.36%,RSD分别为1.3%和1.5%。本方法灵敏、准确,重现性好,可用于石榴不同部位中熊果酸和齐墩果酸含量的测定。

新疆石榴表型性状分析及分子身份证构建

为快速鉴别石榴种质资源,解决石榴“同名异物”、“同物异名”现象,促进新疆石榴产业的发展,本研究在采集新疆石榴主产区24份种质的基础上,分析新疆石榴种质叶片及果实表型性状的变异特征,选择多态性较好的18条引物对石榴种质进行遗传多样性分析及亲缘关系鉴定,并从中选出可将24份石榴种质鉴别出来的核心引物构建新疆石榴的分子身份证。结果表明:新疆石榴的果实、叶片形状变异较大,遗传多样性较为丰富,但仅从表型性状很难将石榴种质进行精准鉴别。18条引物共扩增出240条条带,其中多态性条带199条,占比为82.92%。24份种质的平均等位基因数为1.812 5,有效等位基因数为1.287 0,Nei’s基因多样性指数为0.177 0,Shannon’s多样性指数为0.282 0;和田地区石榴种质的Nei’s基因多样性指数及Shannon’s多样性指数高于喀什地区石榴种质。在遗传相似系数为0.85时,24份石榴种质被分为6大类群,且石榴的分类结果与果实风味和地理位置的关联性不大。5条核心引物UBC73、UBC880、UBC810、UBC841、UBC35可实现24份石榴种质的鉴别,以其扩增的电泳图谱所构建的新疆石榴的分子身份证也互不相同,表明24份种质不存在“同名异物”、“同物异名”现象。本研究结果为石榴种质鉴定提供了一种新方法。

基于网络药理学预测石榴皮抗甲型流感机制及初步药效学验证

目的:基于网络药理学预测石榴皮抗甲型流感的潜在有效靶点及作用机制,并通过动物实验进行验证。方法:通过TCMSP技术平台检索石榴皮的有效成分,筛选其作用的靶标。甲型流感的靶标通过TTD、DRUGBANK等数据库筛选。利用Cytoscape绘制石榴皮抗甲型流感网络图,通过STRING数据库构建蛋白互作网络,并对关键靶标的生物功能进行注释与通路分析。甲型流感病毒感染小鼠,使用酶联免疫吸附试验(ELISA)、蛋白质印迹法(Western blot)检测白细胞介素17(interleukin 17,IL-17)通路中关键蛋白、炎症因子的表达,观测小鼠体质量、肺指数变化。结果:石榴皮中有7个潜在有效成分抗流感病毒、96个有效靶点,其中RELA、MAPK1、JUN、HIF1A、ESR1、NFKBIA、TP53可能为核心靶点,其作用机制可能与IL-17信号通路、化学致癌-受体激活、磷脂酰肌醇3-激酶等通路有关。初步的动物实验显示,石榴皮提取物参与调控IL-17通路,抑制炎症因子白细胞介素6(interleukin 6,IL-6)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素1β(interleukin 1β,IL-1β)、TRAF6(TNF receptor associated factor 6)及核因子κB(nuclear factor kappa-B,NF-κB)p65蛋白表达(P<0.05)。结论:通过预测得出石榴皮中所含的6个成分与不同靶点、通路交互作用,抑制多个炎症因子相关蛋白的表达,进而防治甲型流感。