南高丛越橘与兔眼越橘果实品质及抗氧化能力的比较

以3个南高丛越橘（Vaccinium corymbosum）品种和2个兔眼越橘（V．ashei）品种为试材,进行了果实品质、糖酸组分、抗氧化物质及其能力的比较分析。结果表明,5个品种中,南高丛越橘品种密斯黛（Misty）的果形最大,园蓝（Gardem Blue）果实的可溶性固形物含量最高。而粉蓝（Powderblue）...     

透湿性反光膜覆盖对椪柑果实品质的影响

以桠柑为试材,研究了透湿性反光膜、银灰色反光膜对椪柑果实色泽、可溶性固形物含量、可滴定酸含量和糖含量的影响,并测定了不同反光膜对离地不同高度反射光强度与反射率的影响.结果表明,果园覆盖透湿性反光膜显著提高了树冠中下部的光照,离地80～140cm光照强度为银灰色反光膜的1.8～2倍、不覆盖对照的5.2～6倍.透湿性反光膜...     

仙鹤草多糖含量和抗氧化能力测定

以黔东南产仙鹤草为试材,研究测定了仙鹤草多糖含量和抗氧化能力,以期为仙鹤草开发利用提供依据。结果表明:黔东南产仙鹤草多糖的含量较高(以葡聚糖计),为4.98mg/g,对DPPH自由基的清除率在52μg/mL时达64.1%,312μg/mL时高达93.9%。对DMPD自由基的清除率在52μg/mL时达53.1%,312μg/mL时高达80%。黔东南州产仙鹤草多糖含量较高和抗氧化能力较强,开发价值大。     

不同品种兔眼越橘花粉超微结构与营养成分的观察分析

为探索越橘花粉稔性与超微结构及营养成分的关系,以灿烂、园蓝、粉蓝、杰兔和顶峰5个兔眼越橘品种的花粉为试材,运用透射电镜观察花粉结构及测定了花粉营养成分。结果表明,越橘花粉结构中,内膜系统清晰可见,发育程度因品种而异。花前的花粉细胞核仁较大,蛋白质合成旺盛。通过花粉超微结构与营养成分间关系的分析比较表明,花粉壁的厚度、花粉细胞的蛋白质含量与花粉的萌发率没有相关性。花粉细胞的全糖和脯氨酸含量与花粉发芽率有正相关趋势。内质网发育程度与蛋白质含量呈正相关趋势。     

4个大果沙枣品种抗氧化活性及其成分含量比较分析

以生长在不同地域皀4个大果沙枣品种皀果实为试材,研究其抗氧化活性及不同抗氧化活性成分含量之间皀差异和相兲性。结果表明:4个大果沙枣品种ABTS·+自由基皀清除活性、DPPH自由基皀清除活性、铁氧化还原能力(FRAP)具有显著性差异,‘八卦沙枣’和‘牛奶头沙枣’皀抗氧化活性最高;4个大果沙枣品种之间鞣质、总酚、游离酚、结合酚、黄酮含量均有显著性差异,其中‘大白沙枣’皀总酚、结合酚含量均显著高于其他品种,‘八卦沙枣’皀黄酮含量显著高于其他品种;DPPH、ABTS、FRAP 3个抗氧化测定方法测定4个大果沙枣品种皀抗氧化活性具有显著或极显著相兲性;黄酮含量可作为判断大果沙枣抗氧化活性强弱皀指标。     

枣和酸枣不同器官黄酮含量比较及抗氧化能力分析

为进一步提高枣资源综合开发利用率,以酸枣、过渡(中间)类型和栽培枣共3类种质5个品种为试材,对不同品种不同器官(果实、果皮、果肉、叶片、花、种仁)总黄酮含量及果实黄酮提取液清除羟基自由基(·OH)的能力进行分析测定。结果表明:3类种质的5个品种脆熟期果实的总黄酮含量(以鲜重计)为0.89～3.55 mg/g,平均值为1.94 mg/g;果皮总黄酮含量为4.13～8.21 mg/g,平均值为5.73 mg/g;果肉总黄酮含量为0.17～1.07 mg/g,平均值为0.66 mg/g;花总黄酮含量为3.47～6.90 mg/g,平均值为5.50 mg/g;成熟叶片总黄酮含量为7.01～9.02 mg/g,平均值为7.98 mg/g;种仁总黄酮含量为6.48～14.39 mg/g,平均值为11.43 mg/g。5个品种各器官总黄酮含量的大小顺序为:种仁>叶片>果皮>花>果实>果肉;果实、果肉和叶片中总黄酮含量都是酸枣>中间类型>栽培枣;3类种质脆熟期果实黄酮提取液与·OH清除能力均呈显著正相关。     

不同覆盖方式土壤生态效应与成龄葡萄增产效应研究

通过小区试验研究了不同覆盖保墒灌溉措施对土壤水分动态变化、土壤温度、葡萄生长状况、生理生态指标以及产量等的影响。结果表明:与对照相比,覆盖措施明显减少了土壤水分蒸发,提高了蓄水保墒作用;覆盖措施可明显提高土壤表层温度,但随深度的增大,影响程度逐渐减小;保墒处理的果树生长势强、枝条增长量大、果粒大、产量高。草帘子覆盖措施与塑料薄膜覆盖措施效果相当。     

果园秸秆覆盖时土壤及树体水分与光合速率的关系

旱地果园秸秆覆盖可明显提高土壤含水量、增高树体水势、改善树体水分状况,从而显著提高苹果树的光合速率.覆盖2个月可提高光合速率35.06%,覆盖14个月可提高光合速率48.54%,因此覆盖对早地苹果树的生长发育有重要作用.     

21份李种质果肉总酚含量与抗氧化活性分析

为分析不同李种质果肉总酚含量及其抗氧化能力,进一步提高李资源综合开发利用率,以21份李种质为试材,测定其果肉中总酚含量,采用DPPH法、FRAP法和ABTs法测定其抗氧化能力。结果表明:李果肉中总酚含量丰富且不同种质间差异明显,不同李种质果肉中总酚含量为81.8～1104.9mg/kg,平均含量549.1mg/kg。‘密山大紫李’和03297含量较高,‘玉皇李’含量最低;不同李种质间DPPH自由基清除能力介于25.19～270.61μmol/g,FRAP抗氧化能力介于80.85～1 096.47μmol/g,ABTs抗氧化能力介于74.84～635.59μmol/g。果肉中总酚含量与DPPH、FRAP、ABTs均呈极显著正相关。3种抗氧化评价方法的相关性分析表明,DPPH与FRAP、DPPH与ABTs、FRAP与ABTs相关性均达到极显著水平。     

缺锌胁迫对苹果砧木幼苗抗氧化能力和激素含量的影响

 在人工气候室条件下,采用溶液培养法研究了缺锌胁迫对平邑甜茶（Malus hupehensis Rehd.）和小金海棠（M. xiaojinensis Cheng et Jiang）两种苹果砧木幼苗SOD、POD和CAT的活性,膜质过氧化水平及内源激素IAA、GA3、ZR和ABA含量的影响。结果表明,缺锌胁迫下,两品种叶片和根系中SOD活性显著下降,POD和CAT活性、MDA含量不同程度增加,但小金海棠SOD活性下降幅度较平邑甜茶小,POD和CAT活性增加比例大,且MDA积累量低。缺锌使两种砧木幼苗不同器官中IAA、GA3含量显著降低,ZR、ABA含量增加;小金海棠缺锌植株IAA、GA3、ZR含量较平邑甜茶高,ABA含量低。平邑甜茶缺锌植株膜质过氧化水平高,对缺锌胁迫较敏感,小金海棠在缺锌胁迫下抗氧化能力强,促进生长的激素含量高,对缺锌胁迫有较强的抵御和耐受能力;平邑甜茶缺锌植株膜质过氧化水平高,对缺锌胁迫较敏感。     

Biofortification of Se and induction of the antioxidant capacity in lettuce plants

The aim of the present work is to analyse the way in which Se fertilization in both Se forms applied at different rates can affect the production and accumulation of Se and the foliar antioxidant capacity in lettuce plants Lactuca sativa L. cv Philipus. After different rates of sodium selenate and selenite were applied (5, 10, 20, 40, 60, 80, 120 μmol L⁻¹), the foliar biomass, lipid peroxidation, Se accumulation, antioxidant compounds, and the antioxidant capacity were analysed. Our results indicate that the less toxic form was selenate, as it induced greater biomass, higher Se accumulation, and more antioxidant compounds than did selenite. The treatment of 40 μmol L⁻¹ proved the most suitable for lettuce plants, as the antioxidant capacity and Se accumulation augmented without diminishing biomass, and making the two these lettuce plants healthier than control plants for human consumption, in comparison to control. Finally, regarding the antioxidant capacity test used (the ferric reducing ability of plasma [FRAP], 2,2-diphenyl-1-picryl-hydrazyl [DPPH] and reducing power), only FRAP showed a significant relationship with the different antioxidant compounds, while ascorbate best reflected the effect of Se on the antioxidant capacity under our experimental conditions.     

果袋透光性对宁海白枇杷果实品质及抗氧化能力的影响

以白沙枇杷品种宁海白为试材,分析了白色单层、黄色单层、外浅黄内白双层、黄色双层和外灰内黑双层等5种不同透光率纸袋套袋对枇杷果实品质以及抗氧化能力的影响。结果表明,套袋能提高果实表面的明亮度。套袋后果实的总糖含量较对照下降,下降程度随果袋透光率性的下降而增强,其中外灰内黑纸袋与对照相比差异达到显著水平。套袋还降低了果实的总酚含量、类黄酮含量和果实的抗氧化能力,其中以透光性低的外灰内黑双层纸袋下降最大;但对类胡萝卜素含量影响较少。套袋后果实的抗氧化能力下降,与总酚和类黄酮含量降低呈显著正相关。     

果实色素含量与水溶、脂溶性抗氧化活性的相关性(英文)

色泽和保健作用是果实的2个重要特征.以杨梅(Myrica rubra)、草莓(Fragaria ananassa)、枇杷(Eriobotrya japonica)、桃(Prunus persica)、猕猴桃(Actinidia deliciosa)、椪柑(Citrus reticulata)、脐橙(Citrus sinensis)等果实为材料,研究了不同颜色果实中色素含量与水溶、脂溶性抗氧化活性的相关性.结果表明,深红色荸荠杨梅中的总酚(3 254.7mg/kg)和花青苷(759.4mg/kg)的含量很高,而红色果肉洛阳青枇杷中类胡萝卜素(19 551.3μg/kg)含量较高.叶绿素仅在猕猴桃果实中被检测到.利用PSC法研究果实总抗氧化活性(含水溶和脂溶).结果表明,深红色荸荠杨梅果实提取物的总抗氧化活性(31.14 μmol TE/g)最高,白色果肉的大玉白凤桃提取物的总抗氧化活性(10.34 μmol TE/g)最低.相关性分析结果表明,水溶性抗氧化活性与酚类(R2=0.84)含量呈显著正相关关系,而脂溶性抗氧化活性与类胡萝卜素含量(R2=0.92)都呈显著正相关关系.维生素C是果实中众所周知的水溶性抗氧化物质,然而,研究发现水溶性抗氧化活性与维生素C的含量相关性不显著.含花青苷较丰富的深红色果肉水果和含类胡萝卜素丰富的红色果肉水果都是天然抗氧化物质的良好来源.     

不同包装处理对蓝浆果贮藏期间生理和贮藏性的影响

为了解引种到我国南方栽培的蓝浆果鲜果低温贮藏期间的生理变化状况,并为保鲜贮藏选择适宜的包装材料提供科学依据,研究了在2℃条件下,不同薄膜包装处理对蓝浆果果实贮藏期间可溶性固形物、维生素C、乙醛、乙醇、原果胶和花色苷的含量,以及呼吸强度、多聚半乳糖醛酸酶(PG)和果胶甲酯酶(PE)活性、失重率、腐烂率变化的影响。结果表明,薄膜包装对降低果实失重率和腐烂率具有较好的效果;对降低呼吸强度、抑制多聚半乳糖醛酸酶(PG)和果胶酯酶(PE)的活性以及花色苷含量的下降有一定效果;对减缓贮藏期间可溶性固形物、维生素C和原果胶含量的下降无明显影响。总体看来,0.08mm聚乙烯塑料薄膜(PE)袋适合作为贮藏30d的包装材料。     

Phenolics concentration and antioxidant capacity of different fruit tissues of astringent versus non-astringent persimmons

Astringent and non-astringent persimmon fruits were compared for phenolic compounds, and their antioxidant capacity was studied in both peel and pulp. Fruits that were astringent generally had significantly higher concentrations of phenolics and greater capacities in either tissue. Pulp from astringent persimmons had more phenolics and higher capacity whereas the same was true for peels from non-astringent fruits. Among the methods tested for determining antioxidant capacity (ABTS, DPPH, FRAP, TBARS, SRSA, and HRSA), ABTS showed the best correlation with phenolics concentration while HRSA assays were not sufficiently sensitive to distinguish among genotypes or between fruit tissues. Therefore, we suggest that, for monitoring antioxidant capacity in persimmon, the ABTS method is most suitable.     

防寒措施对越橘越冬微环境和越冬性的影响

以高丛越橘蓝丰为试材,研究了不同防寒措施对大连地区越橘生长微环境变化规律和越冬性的影响。结果表明,2007-2008年冬春大连地区露地极端最低温度、冷驯化及脱驯化期间的最低温度均高于同期越橘能够忍受的最低温度,但露地防寒越橘越冬伤害严重,枝条长度枯死率达53.46%,花芽完全枯死。与对照相比,黑塑料袋外置稻草、黑塑料袋防寒对越冬期间日最低温度、日平均温度、日最高温度影响不大,但明显提高了空气相对湿度,枝条含水量保持在较高水平,1 a生枝条长度及花芽枯死率均较低,防寒效果较好;透明塑料套袋降低了日最低温度,提高了日平均温度、日最高温度和日温度变幅,空气相对湿度略高于对照,越冬后枝条含水量略高于对照,枝条长度及花芽枯死率较高,防寒效果较差。这说明影响大连地区越橘越冬的主要原因是水分胁迫。     

Characterization of blueberry monodehydroascorbate reductase gene and changes in levels of ascorbic acid and the antioxidative capacity of water soluble antioxidants upon storage of fruits under various conditions

Blueberry (Vaccinium corymbosum) is among the richest fruits in ascorbic acid (AA), which is the most important antioxidant involved in the ascorbate–glutathione cycle. In this cycle monodehydroascorbate reductase (MDAR) is the enzymatic component involved in the regeneration of reduced ascorbate. Here we report on the isolation of a full-length cDNA from blueberry encoding a protein of 433 amino acids homologous to the MDARs of Pisum sativum and Vitis vinifera. To assess changes in the expression of blueberry MDAR after harvest, a storage trial was initiated, and the major results were: (1) A dramatic loss in AA occurred under all storage conditions. However, storing fruit under low O₂, combined with high CO₂ level (up to 18%) resulted in better preservation of AA. (2) The antioxidative capacity of water soluble antioxidants (ACW) decreased under all storage conditions, even after 3 weeks storage time, and decreasing O₂ levels did not result in preservation of the ACW. The northern blot hybridization showed a clear differential expression between freshly harvested and stored fruits as well as between fruits stored under various storage condition, in accordance with the above-mentioned changes.     

Effects of conventional and organic nitrogen fertilizers on soil microbial activity,mycorrhizal colonization,leaf antioxidant content,and Fusarium wilt in highbush blueberry (Vaccinium corymbosum L.)

A study was conducted in the greenhouse to determine the effects of conventional and organic nitrogen (N) fertilizer on Fusarium wilt, caused by Fusarium solani, in northern highbush blueberry (Vaccinium corymbosum L. ‘Legacy’). Root colonization by mycorrhizal fungi, soil microbial activity, and leaf antioxidants content was also measured the treatments. Plants grown with organic N fertilizer exhibited a lower incidence of Fusarium wilt than those grown with conventional N fertilizer (5% and 30% by the end of the experiment, respectively). Organic fertilizer also increased the soil biota activity, mycorrhizal colonization, and leaf antioxidant content relative to conventional N source. The results suggest that organic N fertilizer may improve the tolerance of blueberry to soil pathogens, such as F. solani.     

Effects of position on canopy and harvest time on fruit physico-chemical and antioxidant properties in different apple cultivars

Fruit from Granny Smith, Fyriki, Fuji Kiku 8, and Imperial Double Red Delicious apple (Malus domestica Borkh.) trees planted in single or double rows, were harvested from different positions in the canopy, during the last month before commercial harvest. Fruit physico-chemical and antioxidant capacity, using the radical DPPH, were measured, in skin and flesh tissue. Greater total phenol content and total antioxidant capacity per fresh weight and serving portion of skin and flesh tissue, were found in Imperial Double Red Delicious and Fyriki apples, compared to Granny Smith and Fuji Kiku 8. The variation among cultivars in antioxidant contents was greater in peeled, compared with unpeeled fruit, highlighting the importance of eating unpeeled fruit. During the last two weeks before commercial harvest the total phenol content and total antioxidant capacity per fresh weight increased in skin of Granny Smith (by 24% and 42%, respectively) and Fuji Kiku 8 (by 19% and 27%, respectively). Fruit from the more sun—exposed parts of canopy had usually better red coloration and the effect was more pronounced in Fuji Kiku 8 and Fyriki, followed by Imperial Double Red Delicious and a lower effect was found in Granny Smith. Greater total soluble solid content, but not flesh firmness, were also found in fruit from the more sun—exposed parts of canopy, in all cultivars. The skin of fruit from the upper positions in the canopy had greater total phenol content and total antioxidant capacity, in all cultivars, apart from Fyriki. Antioxidant contents in flesh tissue were also greater in the upper positions of canopy in Fuji Kiku 8 and Imperial Double Red Delicious, and to our knowledge this is the first report on plant canopy effects on apple flesh antioxidant compounds.     

Application of and correlation among antioxidant and antiradical assays for characterizing antioxidant capacity of berries

Various antioxidant assays are used to characterize fruits consumed fresh or processed although an easy, reliable and cheap assay is not available to follow the changes in antioxidant power. This study tested the applicability of a recently developed antioxidant measuring system, Water-soluble (ACW) and Lipid-soluble (ACL) Antioxidant Capacity, using the PHOTOCHEM^® instrument. Initially, 13 cultivars of 4 berry species were assayed with Photochem and compared with widely used methods based on single electron transfer reactions like ferric reducing ability of plasma, total polyphenolic content (TPC) and 2,2′-diphenyl-1-picrylhydrazyl radical-scavenging capacity. Assays based on hydrogen atom transfer reactions were also carried out including total radical-scavenger capacity (TRSC). The correlations among the results were all significant at P ≤ 0.05, except the one between TPC and ACW. The overall antioxidant capacity ranked on the order of strawberry < red currant < raspberry < black currant. However, significant differences could have been detected among genotypes and antioxidants assays used for the analysis. The Photochem instrument is not suitable for easy, cheap and high-throughput routine analysis of berry antioxidant capacity and hence is not preferable to other assays.