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Priyadarsini KI Khopde SM Kumar SS Mohan H 《Journal of agricultural and food chemistry》2002,50(7):2200-2206
Ellagic acid, a plant-derived polyphenol, inhibits gamma-radiation (hydroxyl radical) induced lipid peroxidation in rat liver microsomes in a dose- and concentration-dependent manner. Its antioxidant capacity has been estimated using the 1,1-diphenyl-2-picrylhydrazyl radical assay. To understand the actual mechanisms involved in antioxidant activity and the free radical scavenging ability,a nanosecond pulse radiolysis technique has been employed. The rate constants for the reactions of several reactive oxygen species and reactive nitrogen species such as hydroxyl, peroxyl, and nitrogen dioxide radicals have been found to be in the range of 10(6)-10(9) M(-1) s(-1). The ellagic acid radicals have been characterized by the absorption spectra and decay kinetics. Studies on the reactions of ellagic acid with the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) radical and the radicals of ellagic acid with ascorbate have been used to estimate its one-electron reduction potential. Ellagic acid has also been found to be a good scavenger of peroxynitrite. Using stopped-flow reaction analyzer with absorption detection, the rate constant for this reaction has been determined to be 3.7 x 10(3) M(-1) s (-1). The electron spin resonance spectra of the oxidized ellagic acid radicals have been recorded by horseradish peroxidase and hydrogen peroxide method. 相似文献
23.
Abdelwahab SI Hassan LE Sirat HM Yagi SM Koko WS Mohan S Taha MM Ahmad S Chuen CS Narrima P Rais MM Hadi AH 《Fitoterapia》2011,82(8):1190-1197
The in vivo and in vitro mechanistic anti-inflammatory actions of cucurbitacin E (CE) (Citrullus lanatus var. citroides) were examined. The results showed that LPS/INF-γ increased NO production in RAW264.7 macrophages, whereas L-NAME and CE curtailed it. CE did not reveal any cytotoxicity on RAW264.7 and WRL-68 cells. CE inhibited both COX enzymes with more selectivity toward COX-2. Intraperitoneal injection of CE significantly suppressed carrageenan-induced rat's paw edema. ORAC and FRAP assays showed that CE is not a potent ROS scavenger. It could be concluded that CE is potentially useful in treating inflammation through the inhibition of COX and RNS but not ROS. 相似文献
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Marimuthu MP Jolivet S Ravi M Pereira L Davda JN Cromer L Wang L Nogué F Chan SW Siddiqi I Mercier R 《Science (New York, N.Y.)》2011,331(6019):876
Cloning through seeds has potential revolutionary applications in agriculture, because it would allow vigorous hybrids to be propagated indefinitely. However, asexual seed formation or apomixis, avoiding meiosis and fertilization, is not found in the major food crops. To develop de novo synthesis of apomixis, we crossed Arabidopsis MiMe and dyad mutants that produce diploid clonal gametes to a strain whose chromosomes are engineered to be eliminated after fertilization. Up to 34% of the progeny were clones of their parent, demonstrating the conversion of clonal female or male gametes into seeds. We also show that first-generation cloned plants can be cloned again. Clonal reproduction through seeds can therefore be achieved in a sexual plant by manipulating two to four conserved genes. 相似文献
26.
Jayaprakasha GK Jagan Mohan Rao L Sakariah KK 《Journal of agricultural and food chemistry》2003,51(15):4344-4348
Cinnamomum zeylanicum Blume is an important spice and aromatic crop having wide applications in flavoring, perfumery, beverages, and medicines. The steam-distilled volatile oil from cinnamon fruit stalks was analyzed with GC and GC-MS. It showed the presence of hydrocarbons (44.7%) and oxygenated compounds (52.6%). Twenty-seven compounds constituting ca. 95.98% of the volatile oil were characterized. (E)-Cinnamyl acetate (36.59%) and (E)-caryophyllene (22.36%) are found to be major compounds. The volatile oil was screened for its potential as an antioxidant by using in vitro models, such as the beta-carotene-linoleate and phosphomolybdenum complex method. The volatile oil showed 55.94% and 66.9% antioxidant activity at 100 and 200 ppm concentration, respectively. Also, the volatile oil showed good antioxidant capacity, using the formation of the phosphomolybdenum complex. A comparison of the chemical composition of the volatile oil was made with that of buds, flowers, and fruits. This is the first report on the chemical composition of volatile oil of the fruit stalks of this species and its antioxidant activity. 相似文献
27.
Jagan Mohan Rao L Yada H Ono H Yoshida M 《Journal of agricultural and food chemistry》2002,50(11):3143-3146
A methanol extract of nagkesar (buds of Mammea longifolia), which showed strong radical scavenging activity, yielded 13 compounds by separations using column chromatography and HPLC. Structure elucidation of these compounds was achieved by (1)H and (13)C NMR, including DQF-COSY, TOCSY, DEPT, HMQC, HSQC, and HMBC. They include two new compounds, quercetin 3-O-(2' ',4' 'di-E-p-coumaroyl)-alpha-L-rhamno-pyranoside and quercetin 3-O-(3' ',4' '-di-E-p-coumaroyl)-alpha-L-rhamnopyranoside, along with known compounds kaempferol, quercetin, the isopropylidenedioxy derivative of shikimic acid, kaempferol 3-O-(2' ',4' '-di-E-p-coumaroyl)-alpha-L-rhamnopyranoside, kaempferol 3-O-(3' ',4' '-di-E-p-coumaroyl)-alpha-L-rhamnopyranoside, kaempferol 3-O-alpha-L-rhamnopyranoside, quercetin 3-O-alpha-L-rhamnopyranoside, shikimic acid, kaempferol 3-O-beta-D-glucopyranoside, quercetin 3-O-beta-D-glucopyranoside, and beta-sitosterol 3-O-beta-D-glucopyranoside. 相似文献
28.
Mangal Deep Tuti Ramesh Singh Pal Dibakar Mahanta Brij Mohan Pandey Jaideep Kumar Bisht 《Communications in Soil Science and Plant Analysis》2020,51(7):948-962
ABSTRACTLack of crop diversification with suitable vegetable-based cropping system is a major constraint in limiting the productivity and sustainability of north-western Indian sub-Himalayas. To find out a sustainable vegetable-based cropping system in this region, a three year colocasia-based vegetable intensive experiment was conducted at Hawalbagh, Almora, India in a sandy clay loam soil under sub-temperate climatic conditions. Seven colocasia-based vegetable cropping systems along with rice–wheat system were compared under recommended package and practices. The system productivity in terms of colocasia equivalent yield was highest under colocasia–onion–frenchbean (52.38 Mg ha?1) system. Sustainable yield index was highest with colocasia–gardenpea–frenchbean system (0.86). After 3 years, total soil organic carbon (0–5%), available N (2–22%), P (–7% to 14%) and K (3–15%) concentrations were increased in all cropping systems except rice–wheat system, where negative balance of available P (7%) was observed over that of initial soil. Significantly higher soil microbial activity, soil carbohydrate, dehydrogenase, protease, acid and alkaline phosphatases activity were observed under colocasia–onion system. The results suggest that colocasia–onion–frenchbean system with higher productivity improves soil fertility and enhances enzymatic activities. 相似文献
29.
The influence of N-dimethylamino succinamic acid (B-nine) on lucerne plants cv. IGFRI-244 was investigated. B-nine (a growth regulant) was sprayed as a foliar sprays, employing 10, 100, 250, 500, 1000 and 5000 ppm alongwith water spray as control, and the effects were observed on plant growth, flowering, nutritive constituents and seed yield of the crop. Plant height was reduced from 6.19 to 26.85 % in various concentrations of B-nine being highest retardation in 5000 ppm, whereas 250 ppm produced more branches and leaves with dense foliage in comparison to control and other treatments. Delayed flowering by 2–15 days with significant increase in seed yield and 1000 seed weight B-nine bein maximum seed yield in 250 ppm. However, total seed yield was increased by 4.16 to 24.76 per cent over unsprayed control plants. Among the treated levels of B-nine, 250 ppm also gave higher values for Carbohydrate, IVTDMD in shoot of lucerne plants with considerable decreased in 5000 ppm. NDF condent decreased progressively with increased concentration of B-nine but always lesser than the value of IVTDMD. 相似文献
30.