石榴皮抑菌活性物质的初步研究

研究了石榴皮初提物对黄瓜枯萎病菌的室内生物活性.结果表明:在甲醇、氯仿及正己烷提取物中,甲醇提取物的抑菌活性最为显著.采用生长速率法和孢子萌发法测定了石榴皮溶剂萃取物对黄瓜枯萎病菌、番茄灰霉病菌、玉米小斑病菌和棉花立枯病菌等4种病原菌的生物活性.在甲醇提取物的石油醚、氯仿、乙酸乙酯及正丁醇萃取物中,以正丁醇萃取物的抑菌活性最强,在质量浓度为200 g/L时.对4种供试真菌的抑制率均大于70%,而对玉米小斑菌的抑制作用达90.67%,其EC50值为26.2 g/L.     

Development of medical cotton fabrics with Punica granatum L extract finishing for nosocomial infections control

Transmission of pathogenic microorganisms on textile in the hospital settings may contribute to nosocomial infection. This study was aimed to develop a natural antimicrobial finishing on textile that can prevent transmission of pathogenic microorganisms that meets American Association of Textiles Chemists and Colorists (AATCC) standard. Punica granatum L ethanolic extract was shown to have broad spectrum antimicrobial efficacy with bis(6-methylheptyl)-benzene-1,2-dicarboxylate and ethyl-pentadecanoate as the main bioactive constituents. Textile samples developed with the extract finishing exhibited excellent antimicrobial efficacy with a growth reduction of 99.9% on Hoheinstein Challenge Test. The wash durability of the finished textile was found good even after 30 washes with commercial detergent.     

Physico-chemical Properties, Vitamin C Content, and Antimicrobial Properties of Pomegranate Fruit (Punica granatum L.)

Pomegranate (Punica granatum L.) fruit is widely used in the food and process industries due to its excellent nutritional and health value and as a raw material for the manufacture of secondary products such as jellies, dyes, and cosmetics. The objectives of this research were to determine the vitamin C content and antimicrobial properties of fresh and dried fractions of fruit peel and arils of locally grown and imported pomegranate in Oman. A significant variation in vitamin C content was found among the five varieties of pomegranate studied, ranging from 52.8 to 72.0 mg/100 g fresh weight (fw) for arils and 76.8 to 118.4 mg/100 g fw for peels. Irrespective of the variety of pomegranate, vitamin C content in the peel was significantly higher than the aril, with differences ranging from 24.4% to 97.0% depending on variety. Fruit fractions showed antimicrobial effects (inhibition zone) on Staphylococcus aureus and Pseudomonas aeruginosa but not Escherichia coli. Sun drying of fruit peel significantly (p ≤ 0.05) enhanced vitamin C retention and antimicrobial effects in comparison with oven drying presumably due to lower rate of moisture removal associated with low temperature drying over longer duration in comparison with short-time high-temperature oven drying.     

A Comparative Study Between Labeling and Reality: The Case of Phytochemical Composition of Commercial Pomegranate‐Based Products

Manufacturers are deeply involved in the development of new pomegranate‐based products, which have acquired great prestige due to many studies proving their potential health benefits. Commercial pomegranate products including capsules and supplements and juices and nectars were assayed. The contents of the key phytochemical compounds (punicalagin, ellagic acid, and total polyphenolic content) and the associated antioxidant capacity (DPPH^?, ABTS^?+, and FRAP) were analyzed. The experimental ranges of punicalagin and ellagic acid contents were 0.96 to 308 mg/g and 0.09 to 13.1 mg/g, respectively. Punicalagin content was positively correlated (P < 0.001) with DPPH^? and total polyphenolic content values. No significant (P > 0.05) correlation was observed among ellagic acid with the antioxidant capacity. The labeling standardization of these products is necessary due to the wide variability among “theoretically” similar pomegranate‐based products.     

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。     

Total lipids content and fatty acid composition of seed oils from six pomegranate cultivars

The fatty acid composition of the seed oils of six pomegranate (Punica granatum L) cultivars was qualitatively and quantitatively determined by gas chromatography. The seeds contained oil in the range 51-152 mg kg^?1 dry matter. Intervarietal differences in fatty acid composition were demonstrated (fatty acid esters as % (w/w) total fatty acid esters. Sour varieties had the highest while sour-sweet varieties had the lowest oil content. Eleven fatty acids were identified. In all varieties, the predominant fatty acids were linoleic (25.2-38.6%) and oleic acid (24.8-35.5%) followed by palmitic (18.2-22.6%), stearic (6.9-10.4%) and linolenic acid (0.6-9.9%). To a lesser extent arachidic (1.1-3.4%) and palmitoleic acid (0.2-2.7%) were also found in all varieties. Lauric, myristic, behenic and lignoceric acids were rarely detected. As far as we know linolenic (18:3), arachidic (20:0), behenic (22:0) or lignoceric (24:0) acids have not been previously reported in the seed oils of edible pomegranate varieties. Lignoceric acid has not previously been found in pomegranate seed oil.     

Analysis of free and bound aroma compounds of pomegranate (Punica granatum L.)

Volatile aroma compounds were isolated from pomegranate arils by high vacuum distillation (HVD) and solvent extraction with diethyl ether. The HVD distillate exhibited a fresh-fruity and characteristic pomegranate aroma while the total ether extract was devoid of this note in its concentrate. Gas chromatography–mass spectroscopy (GC–MS) analysis revealed the presence of 3-octen-1-yl acetate, trans-3-hexen-1-ol, hexanol and 2-methyl pentanol only in the high vacuum distillate. Ether extract was dominated by 2-heptanol, 2-nonanol and 3-methyl-2-butanol. Based on olfactometric analysis of the HVD isolate, 3-octen-1-yl acetate was identified as the key odorant of pomegranate. Chemical synthesis of this compound, further confirmed its structure. Among the bound aroma compounds, 2-phenylethanol (40%), alpha-terpineol (4.53%) and 2-heptanol (6.35%) were identified as the major compounds existing as glycoconjugates. Identification of the character impact compound and the occurrence of glycosidic precursors in pomegranate are being reported here for the first time.     

Importance of Deoxyribose Degradation Assay for Evaluating Hydroxyl Radical Scavenging Activity of Punica Extract

Punica granatum L. (Family: Punicaceae), commonly known as pomegranate (Anar) has been used traditionally as medicine to treat a number of diseases and disorders. Various parts of the plant and their active constituents are known to possess diverse biological activity. However, little is known about the antioxidant potential of pomegranate fruit peel, which is otherwise considered as waste. Therefore, the concentration-dependent hydroxyl radical scavenging ability of Punica granatum seed and peel extracts (alcoholic and aqueous) using deoxyribose degradation assay were analyzed and compared. The hydroxyl radical scavenging activity at different concentrations of extract (10 to 250 μg/mL) both in presence and/or absence of ascorbic acid and ethylenediamine tetra acetic acid was determined. It was observed that a higher concentration of extract suppresses scavenging activity and lower promotes antioxidant property. Based on the observations, it may be inferred that pomegranate extract, especially from the spent/waste prt, has a strong antioxidant property as assessed by its property of scavenging hydroxyl radical formation.     

不同品种石榴果实挥发成分的SPME-GC-MS分析

采用固相微萃取和气相色谱-质谱联用技术,研究山东枣庄四种主产品种石榴果实的挥发成分,并对其萃取条件进行优化,以期为石榴果实特征香气研究及产品质量控制提供理论依据。通过对固相微萃取条件筛选,确定选用65 μm PDMS/DVB萃取头,在萃取温度60 ℃,萃取时间30 min,解析时间3 min的条件下进行提取分离。石榴果实中共分离鉴定出68种挥发成分,主要包括28种烯类、13种酯类、13种醇类,其中右旋柠檬烯、反式-α-香柑油烯、石竹烯、草酸环己基甲基十三酯、β-蒎烯和反-2-十四烯-1-醇为共有的关键香气成分。通过双向聚类分析将4种石榴品种在剩余信息为65%时分为3类,挥发性成分在剩余信息为10%时将挥发成分分为4类。结果表明,四个品种的石榴在挥发成分上即有共同特征又有各自的独特性和差异性。