Content of bioactive compounds in pungent spice red pepper (paprika) as affected by ripening and genotype

This work was conducted to investigate changes in the bioactive nutrient content of hot (pungent) paprika as a function of ripening in four of the most important varieties cultivated in Hungary. For the quantitative determination, recent liquid chromatographic (HPLC) methods were applied. Forty carotenoids were separated, with β‐carotene and lutein of interest from the biological point of view. The major component of vitamin E was α‐tocopherol. Capsaicin, dihydrocapsaicin and nordihydrocapsaicin were the dominant pungency principles. As for vitamin C components, only ascorbic acid could be detected and determined. The results indicated that all the examined compounds were at low level in the mature green fruits, and the onset of climacteric ripening caused their content to grow. In accord with the advance in ripening, carotenoids were being formed even at the overripening stage, while tocopherols, capsaicinoids and ascorbic acid reached their maximum level at the colour break or red stage and then declined. The highest values with regard to carotenoids were estimated in SZ‐178 and F0‐3 cultivars. The best retention of ascorbic acid was found in SZ‐178, which contained 4.86 mg g^?1 dry matter in the dry pods. On the other hand, retention of α‐tocopherol during ripening and natural drying was found to depend on variety. The highest value for vitamin E was recorded in SZ‐178 followed by K‐V₂, which contained the highest level of α‐tocopherol at the red stage of ripening. © 2001 Society of Chemical Industry     

Evaluation of antioxidant activities of rosehip ethanol extracts in different test systems

Rosehip extracts of 18 samples representing six taxa in the genus Rosa were evaluated for antioxidant activities by use of different test systems. The ferric‐reducing antioxidant power (FRAP) and Trolox‐equivalent antioxidant capacity (TEAC) of the crude extracts ranged from 983.4 to 2187.1 µmol FRAP g⁻¹ dry matter and from 457.2 to 626.2 µmol TEAC g⁻¹ dry matter. The high antioxidant capacity was related to high contents of phytonutrients. The overall mean of antioxidants was 23.23 mg g⁻¹ total carotenoids and 76.26 mg g⁻¹ total phenolics. The phenolic component made a major contribution to the total antioxidant activities in both assays (overall mean was 90.5% and 75.7%), whereas the ascorbate made a minor contribution (8.6% and 16.9%) and the lipophilic component made an even smaller one (0.9% and 7.3%). However, the lipophilic component was the most effective when the comparison was based on the ratio of antioxidant activity to content of antioxidants. The crude extracts exhibited 50.9% (46.6–60.3%) inhibitory effect against the lipid peroxidation induced by 2,2′‐azobis(2,4‐dimethylvaleronitrile) (AMVN) and 85.0% (80.1–90.2%) inhibition in 2,2′‐azobis(2‐amidinopropane)hydrochloride (AAPH) assay at a concentration of 250 µg ml ⁻¹. Ascorbate acted as an antioxidant in both peroxy radical‐induced lipid peroxidations, but as a pro‐oxidant in the metal ion‐induced lipid peroxidation. The crude extracts showed a large inhibitory effect in the ferric ion‐induced lipid peroxidation and caused 83.7% inhibition at a concentration of 25 µg ml ⁻¹ dried rosehip powder. © 2000 Society of Chemical Industry     

拐枣抗氧化活性的研究

用体外化学试验和TLC比较法对拐枣用乙醇、石油醚、乙酸乙酯、正丁醇和水提取物的抗氧化作用和抗氧化成分极性强弱进行了比较分析。结果表明拐枣提取物抗氧化作用从强到弱依次为乙酸乙酯提取物>正丁醇提取物>石油醚提取物>乙醇提取物>水提取物。拐枣具有较强的抗氧化活性,抗氧化活性成分主要存在乙酸乙酯提取物中。     

特殊颜色谷物研究进展和小麦相关新品种创制（网络首发、推荐阅读）

特殊颜色谷物作为一种重要的特殊类型品种,因兼具功能性、营养性和观赏性,愈来愈受到人们的青睐,成为高端农产品创制的热点方向。这些天然色素不仅可以增添食品色泽,还具有抗氧化、抗癌、提高视力等特殊功能。围绕特殊颜色谷物中花青素、麦黄酮和类胡萝卜素等三种重要色素,介绍其生物合成、主要功能和相关作物品种,进而聚焦重要粮食作物小麦,介绍最新培育审定的两种色素类功能性小麦“山农蓝麦1号”和“山农101”（山农黄酮麦1号）。为特殊颜色农作物研究和品种创制提供参考借鉴。     

Comparative study of fatty acid composition,vitamin E and carotenoid contents of palm oils from four varieties of oil palm from Côte d'Ivoire

BACKGROUND: Fatty acid, tocopherol, tocotrienol and carotene contents were assessed in four oil palm species from the National Centre of Agronomical Research of Côte d'Ivoire, two of which were the basal Lamé (HP1) and Deli (HP2) collections and two of which resulted from crossings between HP1 and HP2 varieties of Eleais guineensis, HP3 and HP4 being identified as the first and second cycle selection, respectively. RESULTS: Palm oil species were characterized by the richness in polyunsaturated fatty acids composition (48–60%) compared to saturated fatty acids (40–52%), especially the first variety, which was from the base collection, and the two hybrids ensuing from crossing. Total carotene content of those varieties was higher and accounted for 832–3575 µg g^?1, and the β‐carotene level (580–2390 µg g^?1) was predominant. Total vitamin E content was 864–1124 µg g^?1, with a notable higher content of tocotrienols, especially γ‐and α‐tocotrienol, ranging from 400 to 515 µg g^?1 and from 238 to 350 µg g^?1, respectively. CONCLUSION: Crossing seemed to be useful in improving the performance and analytical characteristics of the base collection materials. Copyright © 2009 Society of Chemical Industry     

Antioxidant Compounds from Vegetable Matrices: Biosynthesis,Occurrence, and Extraction Systems

Natural antioxidants such as vitamin C, tocopherols and tocotrienols, carotenoids, and phenolic compounds are largely distributed in plant products. Most of them are not synthesized by human and need to be introduced with diet according to the Recommended Daily Intake (RDI). This work was aimed to give a comprehensive overview on the occurrence of these antioxidants in plants, in particular in plant foods, on the mechanisms of biosynthesis, and on conventional (liquid–liquid or solid–liquid extraction, Soxhlet) and innovative (enzymatic-assisted, pressurized fluid, supercritical fluid, ultrasound-assisted, microwave-assisted, pulsed electric field) extraction systems.     

干白葡萄酒清除DPPH自由基的能力及其与总酚含量的关系

利用电子自旋共振(ESR)技术对不同品种的干白葡萄酒抗氧化特性进行研究,并分析干白葡萄酒总酚含量与清除DPPH自由基能力的相关性。结果表明,选择ESR测定条件为:干白葡萄酒稀释倍数为30倍,反应时间10min;运用Origin 8.0绘图和数据分析软件对电子自旋共振波谱图进行积分,得到不同品种干白葡萄酒对DPPH自由基的清除率,用Folin-ciocalteus比色法测定总酚含量,长相思葡萄酒清除自由基的能力最强可达到68%,其总酚含量为311mg/L;清除DPPH自由基的能力与总酚含量呈正相关。     

Fatty acid composition and content of tocopherols and carotenoids in raw and extruded grass pea (Lathyrus sativus L)

The effects of adding 140, 180, 220, 260 and 300 g water to 1 kg grass pea seeds and using three levels of extrusion temperature, 90/100/120/100 °C, 120/140/170/160 °C and 140/180/220/200 °C, on concentrations of total lipids, tocopherols, carotenoids and fatty acids in extruded seeds were determined. Extrusion-cooking and a higher moisture content resulted in a lower content of polyenoic fatty acids. The smallest decrease in the content of polyenoic fatty acids in grass pea seeds was observed during extrusion-cooking at 120/140/170/160 °C. Moisturising as well as extrusion lowered significantly the content of the natural antioxidants: α-tocopherol, γ-tocopherol, β-carotene and lutein. © 1999 Society of Chemical Industry