Total Phenolics Content,Antioxidant Capacity,Physicochemical Attributes,and Browning Susceptibility of Different Apple Cultivars for Minimal Processing

The total phenolics content, browning susceptibility, antioxidant capacity, and other physicochemical attributes of five cultivars of apple with different chilling hours requirements were studied to be minimally processed. Granny Smith (GS) and Red Delicious (RD) cultivars (high chill requirement), and Caricia (C), Eva (E), and Princesa (P) cultivars (low chill requirement) were studied. The flesh color, firmness, juiciness, pH, acidity, soluble solids, and flesh browning development, and total phenolics content and antioxidant capacity in flesh and peel were determined. All attributes were significantly different (p ≤ 0.001) among cultivars. RD showed the highest values of soluble solids and pH, and GS, the lowest. GS and P had the highest values of firmness and juiciness. GS, P, and E showed the lowest browning development. RD had the highest phenol content in flesh, followed by E and C. Phenolic content in peel was 2–5 times higher than in flesh for all varieties. The antioxidant capacity of RD flesh was higher than the other four apple cultivars. The antioxidant capacity of the apple peel was 2–4 times higher than the flesh, being RD the highest, followed by C, GS, and P with 50% less. Considering the lower browning development, and higher values of firmness and juiciness, GS and P would be the most suitable cultivars for minimal processing. If fresh-cut apples are not peeled, GS and P would increase their phenolic content in 28–56% and their antioxidant capacity in 65–78%.     

玫瑰香葡萄无核化处理对不同器官中酚类物质和抗氧化能力的影响

 以‘玫瑰香’葡萄为试材,在开花前后使用葡萄专用无核剂（主要成分GA₃）浸蘸果穗,进行无核化处理,通过比色法和体外自由基清除法对不同生长期果实、叶片、嫩茎、卷须等器官中的酚类物质含量和抗氧化能力进行测定。结果表明：无核化处理后,浆果内的酚类物质含量和抗氧化能力显著下降;叶片、嫩茎内酚类物质含量和抗氧化能力有所提高;卷须内酚类物质含量与对照差异不大,抗氧化能力略高于对照;与叶片、嫩茎、卷须等器官抗氧化能力的变化规律相反,无核化处理果实的抗氧化能力低于对照。     

A Comparison Investigation on Antioxidant Activities,Physicochemical Properties and Phytochemical Contents of Kiwifruit Genotypes and Cultivars

The present work was conducted to find the physicochemical properties, chemical components and antioxidant capacity of kiwifruit hydroalcoholic extracts (B-31, HO-1-14, J-242, Bruno, Greenlight, Hayward, Monty, Topstar) grown Yalova, Turkey. Phytochemical tests were performed to determine total phenolic, flavonoid and ascorbic acid. Moreover, the kiwifruit extracts were subjected to evaluate their antioxidant potential using different in vitro assays such as total antioxidant, inhibition of lipid peroxidation, reducing power, metal chelating, free radical, H₂O₂ and superoxide anion scavenging activities at 50–500 μg mL^?1, and also found EC₅₀ and IC₅₀ values. The soluble solid content (SSC), titratable acidity (TA) and pH were analyzed in all the genotypes and cultivars. The highest total phenolic, flavonoid and ascorbic acid content were found in J-242 (89.53 mg GAE/100 g), J-242 (109.13 mg QE/100 g) and HO-1-14 (64.15 mg/100 g), respectively. The linoleic, palmitic, stearic and oleic acid methyl esters were detected in all kiwifruit extracts by GC/MS. Significant differences were found between genotypes and cultivars in the antioxidant tests. The extracts showed high inhibition of lipid peroxidation and compared to standards, significantly (p < 0.05). The GC/MS analyses confirmed quantitative variability in the antioxidant profiles. The SSC, TA and pH of kiwifruit genotypes and cultivars showed a moderate level. The key parameters for the most active kiwifruit included the following: total antioxidant activity for B-31, H₂O₂ scavenging activity for J-242 and metal chelating activity for Topstar. In conclusion, this study exhibited the important role played by the genotypes and cultivars background on the chemical content and antioxidant profiles.     

基于果肉单体酚和总酚含量评价桃果实抗氧化能力

为利用果实酚类物质组分含量评价桃果实的抗氧化能力,以12个红肉桃、7个白肉桃和4个黄肉桃品种成熟期果实为试材,分析果肉单体酚和总酚含量的差异。结果表明,红肉桃各品种具有较高的表儿茶素和总酚含量。在对各指标进行相关性分析的基础上进行主成分分析,将8个酚含量指标概括成4个独立的综合指标（即主成分）,通过隶属函数分析求得各综合指标的隶属函数值,结合权重计算综合评价值并对各品种果肉抗氧化能力进行综合排序,发现红肉桃中的‘北京一线红’综合评价值最高,同时红肉类型排序靠前,多数白肉、黄肉类型排序靠后,与聚类分析结果较一致。试验结果表明桃果实抗氧化能力与肉色密切相关,利用主成分分析法、隶属函数法、聚类分析法结合单体酚、总酚含量可综合评价不同肉色桃果实的抗氧化能力。对桃果实抗氧化能力的贡献排序依次为新绿原酸、总酚、表儿茶素、阿魏酸、绿原酸、芦丁、儿茶素、槲皮素。     

Late season harvest and storage of Rubus berries—Major antioxidant and sugar levels

Late season production of raspberries and blackberries has become more common due to increased consumer demand and new production techniques, but information is scarce regarding the effect on nutritional quality, especially during storage. Antioxidant levels in berries can be influenced by pre-harvest climate conditions (light intensity, day length and temperature) and post-harvest storage time. This study analysed the effect of these factors on the content of different antioxidants (vitamin C, ellagic acid, anthocyanins and total phenolics) in raspberries (Rubus idaeus L. cv. Polka) and blackberries (Rubus fructicosus L. cv. Loch Ness) during storage. The analyses were performed using high performance liquid chromatography (HPLC) with photodiode array detection. Ellagic acid content during storage ranged between 104 and 114 mg/100 g fresh weight in raspberries and 172 and 182 mg/100 g fresh weight in blackberries. Anthocyanin content increased during storage from 64 to 77 mg/100 g fresh weight in raspberries, but decreased from 199 to 162 mg/100 g fresh weight in blackberries. Vitamin C content in raspberries ranged during storage between 22 and 28 mg/100 g fresh weight, but in blackberries values were lower (10–12 mg/100 g fresh weight). Significant changes in total phenolics and sugars occurred during different storage periods (0–9 or 10 days). The results suggest that late season raspberries and blackberries maintain high quality in terms of antioxidant content.     

国家果树种质熊岳李杏圃李资源抗寒性调查

国家果树种质熊岳李杏圃(下简称熊岳李杏圃),位于北纬40°10',东经122°09',年平均气温8.9℃,年日照2887.2h,年降雨量600～700mm。自1983年建圃以来,先后共收集李资源近500个,资源引自我国南北各地及美国、澳大利亚、日本等国。由于资源的原产地不同,其适应性存在着一定的差异,特别是受北方气候条件即特殊的低温年份影响,其抗寒能力表现出明显的不同。如2001年1月我省遭受50年罕见的持续低温和2002年10月的急速降温,李资源遭受到不同程度的冻害,我们于2001年5月和2003年4月对李资源的冻害情况进行了调查。1调查方法2000/2001年冬季冻害主要…     

干燥方式对树莓总酚、总黄酮含量及其体外抗氧化活性的影响

以树莓为试验材料,采用自然干燥、红外干燥、热风恒温干燥和真空冷冻干燥4种干燥方式处理树莓,超声波辅助提取法提取树莓样品中的总酚和总黄酮含量,体外DPPH·和ABTS^+·的清除能力,拓展树莓加工产品方式,提高树莓干燥效率和品质。结果表明:干燥处理后样品中总酚、总黄酮含量及对ABTS^+·和DPPH·清除能力不同程度降低,其中真空冷冻干燥样品总酚和总黄酮含量损失最少,分别为(2.47±0.29)mg·g^-1和(2.06±0.61)mg·g^-1,ABTS^+·和DPPH·清除能力最大,其IC50分别为(4.53±0.04)mg·mL^-1和(5.17±0.12)mg·mL^-1;真空冷冻干燥方式最适宜于树莓的干燥。     

李果实中多酚含量及其抗氧化能力研究

为分析不同李品种果实中多酚含量及其抗氧化能力,以14个李品种为试材,测定果皮和果肉中的多酚含量,采用超氧自由基(O_2~-)清除法、羟自由基(OH·)清除法、DPPH法、FRAP法和TBARS法测定抗氧化能力,比较多酚含量、抗氧化能力的差异,分析多酚含量与抗氧化能力的相关性,比较抗氧化能力测定方法间的相关性。结果表明:(1)李果实中富含多酚并且品种间存在差异,不同品种果皮中含量为1.40~3.37 mg·g~(-1) FW,果肉中含量为0.50~0.97 mg·g~(-1) FW,果皮中含量远大于果肉中含量;果皮中多酚含量较高的李品种为皇后李、猪肝李,其次为黑宝石李、红玫瑰李;果肉中多酚含量最高的为秋姬李,其次为威克逊李。(2)李果皮、果肉多酚提取物均具有较强的抗氧化能力,果皮提取物综合抗氧化能力较强的为皇后李、黑宝石李和猪肝李,果肉的为红美丽李、红玫瑰李和秋姬李。(3)果皮中多酚含量与清除O_2~-、OH·能力及DPPH、FRAP、TBARS均呈极显著正相关,果肉中多酚含量与抗氧化能力呈显著正相关。(4)对5种方法的相关性分析表明,各方法从不同的角度评价李果多酚抗氧化能力,方法间均具有很好的相关性,DPPH法与FRAP法综合评价最佳,可作为主要选择。     

Variation in total phenolics and antioxidant capacity among European plum genotypes

Our objective was to determine the amount of variation in total phenolics and antioxidants present in European plum fruits, so that it can be utilized in breeding programs to enhance the health benefits. Total antioxidant capacity and total phenolic content of the fruit, and the fruit skin color were determined in 20 genotypes, comprising of released varieties and advanced selections of European plums. Among the 20 genotypes, the total antioxidant capacity ranged from 105 to 424 mg ascorbic acid equivalents (AAE)/100 g fresh weight (FW) while the total phenolic content was 86–413 mg gallic acid equivalents (GAE)/100 g FW. The two parameters had a strong correlation of r² = 0.96. A direct correlation between skin color intensity and total phenolic content could also be observed. This study demonstrates that there is adequate variation in total phenolic compounds and antioxidants within European plums and hence there is potential for improvement towards enhancing these health-promoting phytochemicals in this fruit.     

''白玉''枇杷果实套袋对品质及抗氧化能力的影响

以白沙枇杷品种‘白玉’为试材,分析了白色单层、黄色单层、黄色双层和外灰内黑双层等4种纸袋套袋对果实品质以及抗氧化能力的影响。结果表明,套袋能改善果实表面的光泽度。白色单层纸袋处理增加了果实的可溶性固形物和总糖含量,而其他3种纸袋处理都导致果实可溶性固形物和总糖含量下降,可滴定酸含量上升。套袋还降低了果实的总酚含量、类黄酮含量和抗氧化能力,其中以外灰内黑双层纸袋下降最大。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。综合套袋对果实品质的影响,‘白玉’枇杷宜用透光性好的白色单层纸袋。     

钾与钙和硅混合喷施对番茄抗逆性物质含量的影响

研究了钾、钙和硅的混合喷施对番茄叶片中的可溶性糖和水溶性总酚含量的影响。结果表明:叶面喷施钾溶液及其与钙和硅溶液的搭配使用均可显著提高叶片中可溶性糖的积累量,分别增加了68%和129%,即钾、钙和硅溶液同时使用的效果最显著;而对于水溶性总酚含量,叶面喷施钾溶液的效果最好,显著地高于其它处理,其次是混合喷施钾、钙和硅溶液,显著高于对照处理,2个处理分别比对照增加了10.1%和5.2%。     

‘白玉’枇杷果实套袋对其品质及抗氧化能力的影响

 以白沙枇杷品种‘白玉’为试材,分析了白色单层、黄色单层、黄色双层和外灰内黑双层等4种纸袋套袋对果实品质以及抗氧化能力的影响。结果表明,套袋能改善果实表面的光泽度。白色单层纸袋处理增加了果实的可溶性固形物和总糖含量,而其他3种纸袋处理都导致果实可溶性固形物和总糖含量下降,可滴定酸含量上升。套袋还降低了果实的总酚含量、类黄酮含量和抗氧化能力,其中以外灰内黑双层纸袋下降最大。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。综合套袋对果实品质的影响,‘白玉’枇杷宜用透光性好的白色单层纸袋。     

我国李的引种栽培及研究概况

对国外的李品种选育与栽培利用概况和我国李品种的引进栽培现状进行了研究。同时，对国外李品种在我国的栽培及相应的适应性、配套技术研究进行了综述，并提出了目前相关研究工作中存在的主要问题。     

Antioxidant Capacity,Phenolic Compounds and Antioxidant Enzymes of Wild Grape Seeds from Different Accessions Grown in Iran

Grape seeds contain high levels of phytochemicals, that have been associated with a reduced risk of chronic diseases. In this study, the polyphenolic content, antioxidant capacity and antioxidant enzymes activity in the seeds of 20 wild grape accessions native to Iran were investigated. The antioxidant capacity of the wild grape seeds was evaluated by DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and Fe²⁺ chelating. Total phenolic (TP), total flavanoid (TF) and total proanthocyanidin (TPA) content ranged from 44.86 to 155.1, 23.21 to 131.91, and 10.11 to 26.10?mg/g seed, respectively. All seed extracts showed remarkable DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and Fe²⁺ chelating ranging from 27.34 to 78.57%, 198.83 to 590.86?µmol TE/g and 23.12 to 62.98%, respectively. Grape seed extracts had the greatest antioxidant enzymes activity guaiacol peroxidase (G-POD), superoxide dismutase (SOD), and catalase (CAT). Based on HPLC analyses, catechin was the most abundant compound identified (25.89?mg/g) for all accessions. Additionally, significant correlations among different antioxidant assays were found. With the high amount of total phenolic content, antioxidant capacity and antioxidant enzymes activity, seeds of P6, P7 and P8 accessions might be evaluated as a nutritional supplement.     

李果实氨基酸种类和含量分析

利用氨基酸自动分析仪测定了福建8个李品种的氨基酸组成和含量。结果表明,李果实中氨基酸含量高,种类丰富,其中田黄李中含量最高,达492.84mg/100g。不同李品种已检测的17种氨基酸中,均以天冬氨酸含量最高;必需氨基酸含量为59.23～100.41mg/100g,占总氨基酸的20.42%;儿童必需氨基酸含量也很高,平均可达14.60mg/100g;味觉氨基酸含量高,其中田黄李的味觉氨基酸在测试的8种李品种中最高。李果实中药效氨基酸的含量也很丰富,以天冬氨酸、谷氨酸和赖氨酸为主,总量以皇后李最高、田黄李次之,分别为366.95和355.49mg/100g。     

国外鲜食良种李品种引种表现及综合评价

在对引种的25个李优良品种随机抽取20个果实的相关性状和指标进行观察分析和测定的基础上,应用灰色关联分析法,对各品种进行综合评价,选择出3个在南阳表现较好的优良品种,为科学、合理地选育果树新品种提供了新的方法和科学依据.     

不同熏蒸保鲜剂对‘巨峰’葡萄抗氧化能力的影响

以‘巨峰’葡萄为试材,对比分析了不同浓度二氧化氯(5、10、15mg·L^-1)和臭氧(30、60、90mg·m^-3)熏蒸处理对低温贮藏过程中葡萄总酚、原花青素、丙二醛(MDA)含量及多酚氧化酶(PPO)、过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)活性的影响,以期为‘巨峰’葡萄采后贮藏保鲜提供参考依据。结果表明:与对照相比,一定浓度熏蒸保鲜处理均在不同程度上抑制了‘巨峰’葡萄总酚和原花青素的降解,保持较好的细胞膜完整性,抑制了MDA含量和PPO活性的增加,贮藏后期维持较稳定的POD和较高的CAT与SOD活性。综合分析表明,6个熏蒸处理中,10mg·L^-1ClO₂和60mg·m^-3O₃能够延缓葡萄的衰老进程,保持较好的抗氧化能力和贮藏品质。     

Antioxidant phytochemicals in cabbage (Brassica oleracea L. var. capitata)

Eighteen different cabbage cultivars were assayed for variability between the cultivars for the antioxidant phytonutrients. The Vitamin C content ranged from 5.66 to 23.50 mg/100 g fresh weight. The maximum Vitamin C content was recorded in cultivar Sprint Ball (23.50 mg/100 g), followed by cv. Gungaless (12.86 mg/100 g). The β-carotene content in cabbage ranged from 0.009 to 0.124 mg/100 g fresh weight. The maximum β-carotene content was recorded in cv. Quisto (0.124 mg/100 g), followed by Green Challenger (0.115 mg/100 g) and Rare Ball (0.114 mg/100 g). The minimum values for β-carotene was noted in cv. Pusa Mukta (0.009 mg/100 g). Lutein content was also recorded in the cabbage cultivars, which ranged from 0.021 to 0.258 mg/100 g fresh weight. Maximum lutein content was recorded in Quisto (0.258 mg/100 g) and minimum in Pusa Mukta (0.021 mg/100 g). Vitamin E (dl-α-tocopherol) was estimated only in 14 cabbage cultivars, which ranged from 0.030 to 0.509 mg/100 g fresh weight. Maximum α-tocopherol content was recorded in Rare Ball (0.509 mg/100 g) and minimum in Green Cornell (0.030 mg/100 g). Total phenol content was also estimated only in 14 cultivars and the values ranged from 12.58 to 34.41 mg/100 g fresh weight. Amongst the three different cultivated forms of cabbage, red cabbage had higher Vitamin C (24.38 mg/100 g), dl-α-tocopherol (0.261 mg/100 g) and phenolic content (101.30 mg/100 g) as compared to the white cabbage and savoy cabbage.     

鲜食葡萄品种多酚类物质含量及抗氧化活性分析

以6个主要鲜食葡萄品种为试材,利用比色和荧光分光光度法测定葡萄的果皮、果肉、种子和果梗中花青素、总酚和总黄酮含量,分析了清除氧自由基(ORAC)、1,1-二苯基-2-三硝基苯肼自由基(DPPH·)和铁离子还原(FRAP)能力与多酚类物质之间的相关性。结果表明:葡萄品种多酚类物质主要以黄酮类化合物为主,其中花青素在果皮以及总酚和总黄酮在种子和果梗中含量较高,但多酚类物质在果肉中最低。葡萄品种‘夏黑’果皮中花青素、总酚和总黄酮含量均高于其它葡萄品种。以‘巨玫’果皮和果肉花青素、总酚和总黄酮含量最高,但‘青提’果皮和果肉中花青素、总酚和总黄酮含量均低于其它葡萄品种。通过分析各葡萄品种抗氧化活性与多酚类物质之间的关系发现,果皮中FRAP和ORAC清除率以及种子和果梗中DPPH·清除率与花青素、总酚及总黄酮之间均呈显著性正相关,且多酚类物质含量较高说明其抗氧化活性较强。     

桑黄总黄酮含量及其体外抗氧化活性研究

为了探讨桑黄抗氧化作用的物质基础,进一步开发其药用功能,本试验测定了6种不同来源的桑黄样品中总黄酮含量及其体外总抗氧化活性、清除·OH能力和清除O2-·能力,分析其总黄酮含量与体外抗氧化活性的量效关系。结果表明,不同来源的桑黄总黄酮含量存在差异。各样品均具有较好的体外抗氧化活性,其中野生桑黄SH-2最佳。桑黄体外总抗氧化活性、清除·OH能力和清除O2-·能力与总黄酮含量的相关性都达到极显著水平（P〈0．01）。