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61.
The genus Cyclopia (Fabaceae family) includes a number of shrubs endemic to Cape Fynbos region of South Africa. The most common of these plants is Cyclopia intermedia E. Mey., used together with other Cyclopia species (mainly C. subternata and C. sessiliflora) to manufacture the honeybush herbal tea which has been produced in South Africa roughly since the beginning of the 19th century. Honeybush infusions are gaining popularity due to their characteristic honey-like flavour, low tannin content, absence of caffeine and potential health effects related to their antimutagenic and antioxidant properties. 相似文献
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63.
In recent years, colored sorghum genotypes high in flavonoids have been developed. Flavonoid levels of eight black sorghum genotypes grown in four locations in Texas were evaluated to assess the relative genotype, environment and genotype × environment effects. Levels of total 3-deoxyanthocyanidins ranged from 292 μg/g to 499 μg/g and 251 μg/g to 804 μg/g across environments and genotypes, respectively. Total 3-deoxyanthocyanidins in sorghums from Halfway were low (178–694 μg/g) due to the reduction of their non-methoxylated forms. This reduction is likely due to significant grain weathering which was observed only at Halfway. In addition, flavanone and flavone levels were the lowest at Halfway with levels of 12 μg/g and 78 μg/g, respectively. For all flavonoids there was a genotype by environment interaction (p < 0.01) which suggests that environment had a different effect on flavonoid levels depending on the genotype. Color values L*, a* and b* did not correlate with flavonoid content. Due to genotype, environment and their interactions, sorghum breeders must evaluate these traits in multiple environments to identify genotypes with high and stable production of flavonoid compounds. 相似文献
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65.
Gaultheriadiolide (1), a new compound, together with the known dauosterol (2), ginkgetin (3), myricetin (4), 6-ethyl-5-hydroxy-2,7-dimethoxy-1,4-naphthoquinone (5), ursolic acid (6), methyl salicylate 2-O-β-d-xylosyl(1→6)β-d-glucopyranoside (7), and methyl salicylate 2-O-β-d-glucopyranoside (8) were isolated from Gaultheria yunnanensis. The structure was elucidated on the basic of spectral analysis, especially 1D and 2D NMR. Primary bioassays showed that compound 1 had medium cytotoxic activity against HEp-2 and HepG2 Cells, with IC50 of 23.337 μM and 29.4497 μM, respectively. 相似文献
66.
Rita Pernice Mario Parisi Italo Giordano Alfonso Pentangelo Giulia Graziani Monica Gallo Vincenzo Fogliano Alberto Ritieni 《Scientia Horticulturae》2010
Carotenoids and flavonoids are the main tomatoes antioxidants, having an important role for human health. This study investigates the effects of different water regime and of the industrial processing on the concentration of these compounds in tomato fruits and in tomato products. Two biotypes of Corbarini small tomatoes were cultivated in the Sarno valley (Salerno, Italy) using three different water regimes. A biochemical characterization of the fresh and of the corresponding canned products was performed. Results show that water regime influenced the antioxidant profile of tomato fruits, with marked differences between the two biotypes. Data obtained highlight that water regime markedly influenced the productivity and the quality of the tomatoes. Results also demonstrated that industrial process increased carotenoids content without causing a significant flavonoids degradation. 相似文献
67.
[目的]为更好地利用马蹄加工皮渣中的资源,优化马蹄皮渣中总黄酮的微波提取工艺,得到得率较高的黄酮类化合物。[方法]采用 Box-Behnken中心组合响应面法优化马蹄粉加工皮渣中总黄酮的微波提取工艺,建立了不同影响因素与马蹄总黄酮得率之间的函数关系。[结果]确定最佳提取工艺条件为:乙醇浓度55.4%,料液比1:30 g/ml,微波功率320 W,微波3 min,在此条件下重复提取2次,理论得率为2.376%,经过验证得到总黄酮得率为2.365%,实测值与理论预测值之间的相对误差为0.461%。[结论]优化得到的提取工艺可靠,可为马蹄加工废弃物的综合高效利用提供参考依据。 相似文献
68.
B. Dave Oomah Nathalie Tiger Mark Olson Parthiba Balasubramanian 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):86-92
Eight lupin (Lupinus angustifolius L.) genotypes grown at four locations in south central Alberta in 2004 were evaluated for variability in phenolic constituents and antioxidant activity measured by a photochemiluminescence assay. Genotype was the main source of variation for content of phenolic compounds and antioxidant activities. Phenolic compounds in genotypes varied minimally from 11.9 to 14.7 mg catechin equivalent and 4.15 to 4.95 mg rutin equivalent g−1 lupin for total phenolic and flavonoid contents, respectively. Lupin genotypes exhibited weak antioxidant activity based on water–soluble substances (ACW) of 0.54 to 1.07 μmole Trolox equivalent antioxidant capacities (TEAC)/g with lag time ranging from 70 to 153 s and an antioxidant index of 6.7 to 14.5 and 1.9 to 3.3 μmole TEAC/g based on measurements of lipid-soluble substances (ACL). Antioxidant activity of lupin genotypes was not related to phenolic contents of seeds. 相似文献
69.
Perazzini R Leonardi D Ruggeri S Alesiani D D'Arcangelo G Canini A 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):211-218
Eight Phaseolus vulgaris L. landraces cultivated on farm in marginal areas of Central Italy (Lazio region) were investigated in order to evaluate
chemical composition of storage proteins and secondary metabolites fractions. The total protein content showed some differences
among landraces; the maximum value was next to 30 g for 100 g of dry weight. The seed storage proteins were screened by polyacrylamide
gel electrophoresis (SDS/PAGE): seven landraces exhibited phaseolin patterns type S, one landrace showed a phaseolin pattern
type T. A morphological analysis of cotyledon parenchyma performed by scanning electron microscopy (SEM) revealed differences
in size of starch granules. Moreover the polyphenolic composition was investigated using HPLC-APCI; from the methanol extracts
a flavonoid, kaempferol, and a coumarin, 5,7-dimethoxycoumarin, were identified. To our knowledge, this is the first time
that 5,7-dimethoxycoumarin has been reported in P. vulgaris seeds. 相似文献
70.