排序方式： 共有6条查询结果，搜索用时 15 毫秒
1
1.
Stupans I Kirlich A Tuck KL Hayball PJ 《Journal of agricultural and food chemistry》2002,50(8):2464-2469
Typical components of the Mediterranean diet, such as olive oil and red wine, contain high concentrations of complex phenols, which have been suggested to have an important antioxidant role. The aim of the present work was to determine the inhibitory potency of compounds such as oleuropein, hydroxytyrosol, and other structurally related compounds, such as gallic acid, toward reactive oxygen species generation and free radical scavenging ability. The potency of these compounds was also examined with respect to protecting in vitro low-density lipoprotein oxidation. These studies indicate that complex phenols, such as hydroxytyrosol, and gallic acid both inhibit free radical generation and act as free radical scavengers. The use of three different approaches to determine antioxidant potency demonstrates that activity in one test does not necessarily correlate with activity in another. It was also demonstrated that the presence of two phenolic groups is not always associated with antioxidant activity. 相似文献
2.
Rimvydas Vasaitis Vaidotas Lygis Ieva Vasiliauskaite Albertas Vasiliauskas 《European Journal of Forest Research》2012,131(4):1211-1216
In forest stands, Picea abies is commonly subjected to logging and bark stripping injuries. Most mechanical wounds do not exceed 300 cm2, but their pathological consequences are unclear. The aim of the study was to estimate the rate of wound occlusion and the probability of decay in P. abies stems in relation to initial wound size and wounding season. The study included forty-five stems with 1-, 2-, 3-, 4- and 5-cm-wide by 15-cm-long wounds (15–75 cm2), and eighty-three stems with 15-cm-wide by 20-cm-long wounds (300 cm2), made either in January or in August. After 19–21 years, each wound was assessed for occlusion rate and the presence of decay. All 1- to 2-cm-wide wounds were occluded, compared to 58–70% of the 3- to 4-cm-wide wounds, 25% of the 5-cm-wide wounds, and 0% of the 15-cm-wide wounds. On average, it took 3.6, 5.5, 10.4, 12.7 and 14.7 years to occlude wounds ranging in size from 1- to 5-cm-wide, respectively. After 21 years, the observed size of wounds comprising an initial area of 300 cm2 ranged between 14 and 481 cm2. Wounding season and stem DBH had no impact on wound healing. Wound decay incidence correlated positively with the initial width of injury (r = 0.925; P < 0.05). All 1- to 2-cm-wide wounds lacked any decay, while the proportions of decay among 3-, 4-, 5- and 15-cm-wide wounds were 58.3, 50.0, 83.3 and 100%, respectively. Length of decay comprised 35–225 cm. Consequently, wounds on P. abies stems greater than 5 cm width are unlikely to be occluded and more prone to decay development. 相似文献
3.
Ieva Jokubauskaite Danute Karčauskienė Alvyra Slepetiene Regina Repsiene Kristina Amaleviciute 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2016,66(8):647-652
ABSTRACTA meta-analysis of 297 treatment data from the Vezaiciai Branch of the Lithuanian Research Centre for Agriculture and Forestry long-term field experiment published from 2006 to 2015 was used to characterize the changes in SOC under different fertilization treatments and residue management practices in Lithuania’s acid soil. A meta-analysis was performed to quantify the relative annual change (RAC) of SOC content and the average RAC rate of SOC under four fertilization modes (farmyard manure (FYM) (40?t?ha?1)); alternative organic fertilizers (in the manure background (40?t?ha?1)); FYM (60?t?ha?1); alternative organic fertilizers (in the manure background (60?t?ha?1)) in two soil backgrounds (naturally acid and limed soil). The average RAC under four fertilization modes was 1.46 g?kg?1?yr?1, indicating that long-term fertilization had considerable SOC sequestration potential. Incorporation of alternative organic fertilizers in unlimed soil showed negative effects (?0.39 and ?0.66 g?kg?1?yr?1) in the observed long-term experiment. The RAC in the limed soil with incorporated organic fertilizers (FYM and alternative organic fertilizers), compared to the control, and varied from 0.25 g?kg?1?yr?1 in the treatment with incorporated alternative organic fertilizers (in the manure background (40?t?ha?1)) to 0.71 g?kg?1?yr?1 in the soil with FYM (60?t?ha?1). In this study, the average RAC rate of SOC under organic fertilization treatments in limed soil (5.07–6.54%) was longer than organic fertilization in unlimed soil (2.11–3.49%), which might be attributed to the application of organic manure that would result in a slow release of fertilizer efficiency. Our results indicate that the application of manure (40 or 60?t?ha?1) showed the greatest potential for C sequestration in agricultural soil and produced the longest SOC sequestration duration. 相似文献
4.
Structural characterization of the metabolites of hydroxytyrosol, the principal phenolic component in olive oil, in rats 总被引：1，自引：0，他引：1
Hydroxytyrosol is quantitatively and qualitatively the principal phenolic antioxidant in olive oil. Recently it was shown that hydroxytyrosol and five metabolites were excreted in urine when hydroxytyrosol was dosed intravenously or orally in an olive oil solution to rats. The conclusive identification of three metabolites of hydroxytyrosol by MS/MS as a monosulfate conjugate, a 3-O-glucuronide conjugate, and 4-hydroxy-3-methoxyphenylacetic acid (homovanillic acid) has been established in this investigation. The structural configurations of the glucuronide conjugate and 4-hydroxy-3-methoxyphenylacetic acid were confirmed by (1)H NMR. The radical scavenging potencies of homovanillic acid, homovanillic alcohol, hydroxytyrosol, and the metabolites were examined with the radical 2,2-diphenyl-1-picrylhydrazyl. These studies showed them to be potent antioxidants with SC(50) values of 14.8 and 11.4 microM for homovanillic acid and homovanillic alcohol, respectively. The 3-O-glucuronide conjugate was more potent than hydroxytyrosol, with an SC(50) of 2.3 in comparison to 11.0 microM, and the monosulfate conjugate was almost devoid of radical scavenging activity. 相似文献
5.
Ieva AlaunyteValentina Stojceska Andrew PlunkettPaul Ainsworth Emma Derbyshire 《Journal of Cereal Science》2012,55(1):22-30
The growing interest in the benefits of wholegrain products has resulted in the development of baked products incorporating less utilised and ancient grains such as, millet, quinoa, sorghum and teff. However, addition of wholegrains can have detrimental effects on textural and sensory bread product qualities.Enzymes can be utilised to improve breadmaking performance of wholegrain flours, which do not possess the same visco-elastic properties as refined wheat flour, in order to produce a healthy and consumer acceptable cereal product.The effects of Teff grain on dough and bread quality, selected nutritional properties and the impact of enzymes on physical, textural and sensory properties of straight dough and sourdough Teff breads were investigated.Teff breads were prepared with the replacement of white wheat flour with Teff flour at various levels (0%, 10%, 20%, and 30%) using straight dough and sourdough breadmaking. Different combinations of enzymes, including xylanase and amylase (X + A), amylase and glucose oxidase (A + GO), glucose oxidase and xylanase (GO + X), lipase and amylase (L + A) were used to improve the quality of the highest level Teff breads. A number of physical, textural and sensory properties of the finished products were studied. The nutritional value of breads was determined by measuring chemical composition for iron, total antioxidant capacity, protein, fibre and fat. The obtained results were used to estimates intakes of nutrients and to compare them with DRIs.The incorporation of Teff significantly (P < 0.05) improved dietary iron levels as 30% Teff breads contained more than double the amount of iron when compared to corresponding wheat bread (6 mg/100 g v 2 mg/100 g). Addition of Teff also significantly (P < 0.05) improved total antioxidant capacity from 1.4 mM TEAC/100 g to 2.4 mM TEAC/100 g. It was estimated that an average daily allowance of 200 g of Teff enriched bread would contribute to DRIs in the range of 42-81% for iron in females, 72-138% for iron in males; 38-39% for protein in males, 46-48% for protein in females; and 47-50% of fibre in adults.The major challenge was encountered in producing the highest level of Teff bread with good textural and sensory attributes. Increasing the level of Teff significantly (P < 0.05) increased dough development time, degree of softening, crumb firmness and bitter flavour whilst decreasing the dough stability, specific loaf volume and overall acceptability of the bread. Teff breads produced with the addition of enzyme combinations showed significant improvements (P < 0.05) in terms of loaf volume, crumb firmness, crumb structure, flavour and overall acceptability in both straight dough and sourdough breadmaking. 相似文献
6.
1