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461.
Pritpal Singh Dinesh Kumar Benbi 《Communications in Soil Science and Plant Analysis》2020,51(9):1184-1203
ABSTRACT The performance of DNDC (DeNitrification-DeComposition) and RothC (Rothamsted Carbon model) in simulating soil organic carbon (SOC) storage in soils under rice (Oryza sativa L.) – wheat (Triticum aestivum L.), maize (Zea mays L.) – wheat and cotton (Gossypium hirsutum L.) – wheat cropping systems was evaluated on field and regional scale. Field experiments consisted of N, NP, NK, PK, NPK, FYM, N + FYM, NPK + FYM, and control (UF) treatments. DNDC and RothC over-estimated SOC storage by 0.35–1.16 Mg C ha?1 (6–21%) in surface layer with manure application, compared with inorganic fertilizer treatments by 1.01–1.16 Mg C ha?1 (14–18%). Although RothC only slightly over-estimated SOC stocks, DNDC provided a better match for measured versus simulated SOC stocks (R 2 = 0.783*, DNDC; 0.669*, RothC, p < .05). Model validation on independent datasets from long-term studies on rice–wheat (R 2 = 0.935**, DNDC; R 2 = 0.920**, RothC, p < .01) and maize–wheat (R 2 = 0.895** for DNDC and R 2 = 0.967** for RothC, p < .01) systems showed excellent agreement between measured and simulated SOC stocks. On a regional scale, change in SOC storage under Scenario 1 (NPK) was significant up to 8 years of simulation, with no change thereafter. In Scenario 2 (NPK + FYM), DNDC simulated SOC storage after 10 years was 2.0, 0.4, and 1.4 Mg C ha?1 in three systems, respectively. Amount of C sequestered in silt + clay fraction varied between 0.31 and 0.97 kg C 10 years?1 (Mg silt + clay)?1 under Scenario 1, and between 0.78 and 2.67 kg C 10 years?1 (Mg silt + clay)?1 under Scenario 2. 相似文献
462.
Separation, identification, quantification, and method validation of anthocyanins in botanical supplement raw materials by HPLC and HPLC-MS 总被引:6,自引:0,他引:6
A method has been established and validated for identification and quantification of individual, as well as total, anthocyanins by HPLC and LC/ES-MS in botanical raw materials used in the herbal supplement industry. The anthocyanins were separated and identified on the basis of their respective M(+) (cation) using LC/ES-MS. Separated anthocyanins were individually calculated against one commercially available anthocyanin external standard (cyanidin-3-glucoside chloride) and expressed as its equivalents. Amounts of each anthocyanin calculated as external standard equivalent were then multiplied by a molecular-weight correction factor to afford their specific quantities. Experimental procedures and use of a molecular-weight correction factors are substantiated and validated using Balaton tart cherry and elderberry as templates. Cyanidin-3-glucoside chloride has been widely used in the botanical industry to calculate total anthocyanins. In our studies on tart cherry and elderberry, its use as external standard followed by use of molecular-weight correction factors should provide relatively accurate results for total anthocyanins, because of the presence of cyanidin as their major anthocyanidin backbone. The method proposed here is simple and has a direct sample preparation procedure without any solid-phase extraction. It enables selection and use of commercially available anthocyanins as external standards for quantification of specific anthocyanins in the sample matrix irrespective of their commercial availability as analytical standards. It can be used as a template and applied for similar quantification in several anthocyanin-containing raw materials for routine quality control procedures, thus providing consistency in analytical testing of botanical raw materials used for manufacturing efficacious and true-to-the-label nutritional supplements. 相似文献
463.
Aqueous extracts of the leaves of Ardisia compressa (AC) have been used in folk medicine to treat various liver disorders including liver cancer. The objective of this study was to partially characterize and determine the total polyphenol content, antioxidant capacity, and quinone reductase activity of A. compressa tea in comparison to mate (Ilex paraguariensis, MT) and green (Camellia sinensis,GT) teas. Total polyphenol content, antioxidant capacity, and phase II enzyme induction capacity were measured by the modified Folin-Ciocalteu, ORAC, and quinone reductase (QR) assays, respectively. The major polyphenols in AC were not catechins. HPLC retention times and standard spikes of AC indicated the presence of gallic acid, epicatechin gallate, ardisin and kaempferol. Using catechin as standard, the total polyphenol value of AC (36.8 +/- 1.1 mg/mg DL) was significantly lower than GT (137.2 +/- 5.8 mg equivalent of (+)-catechin/mg dried leaves, DL) and MT (82.1 +/- 3.8 mg/mg DL) (P < 0.001). Antioxidant capacity (AC, 333; GT, 1346; MT, 1239 mmol Trolox equivalents/g DL) correlated with total polyphenol values (r(2) = 0.86, P < 0.01). AC (4.5-12.5 microg/mL) induced QR enzyme, in Hepa1c1c7 cells, up to 15%. MT and GT showed no induction at the concentrations tested (0.5-10.5 and 0.5-12.5 mg/mL, respectively). These results suggest that AC has a different mechanism of protection against cytotoxicity that is not related to its antioxidant capacity. Further studies are needed to determine such mechanisms and to explore its potential as a chemopreventive or therapeutic agent. 相似文献
464.
Soils from six different regions of the State of Uttar Pradesh, India, were treated with 1% and 2% concentrations of castor oil and incubated for 15 days and 30 days time. The erosion coefficients of natural as well as treated soils were determined with a simple laboratory erosion apparatus. The castor oil was found to be highly effective in reducing soil erosion. It was more effective in light texture soils with reduction in erosion coefficients to the extent of 88 70. Heavy textured soils also registered good reduction in erosion coefficient, to the extent of 20 %. The castor oil was effective in both the concentrations and both the incubation periods. Similarly, it was effective at all the four slope levels viz. 1, 2, 4 and 8%. The castor oil has been found much superior than cellulose and protein as far as their capability to check soil erosion is concerned. 相似文献
465.
Fixation and defixation of ammonium in soils: a review 总被引:2,自引:0,他引:2
Fixed NH4+ (NH4+
f) and fixation and defixation of NH4+ in soils have been the subject of a number of investigations with conflicting results. The results vary because of differences
in methodology, soil type, mineralogical composition, and agro-climatic conditions. Most investigators have determined NH4+
f using strong oxidizing agents (KOBr or KOH) to remove organic N and the remaining NH4+
f does not necessarily reflect the fraction that is truly available to plants. The content of native NH4+
f in different soils is related to parent material, texture, clay content, clay mineral composition, potassium status of the
soil and K saturation of the interlayers of 2:1 clay minerals, and moisture conditions. Evaluation of the literature shows
that the NH4+
f-N content amounts to 10–90 mg kg−1 in coarse-textured soils (e.g., diluvial sand, red sandstone, granite), 60–270 mg kg−1 in medium-textured soils (loess, marsh, alluvial sediment, basalt) and 90–460 mg kg−1 in fine-textured soils (limestone, clay stone). Variable results on plant availability of NH4+
f are mainly due to the fact that some investigators distinguished between native and recently fixed NH4+ while others did not. Recently fixed NH4+ is available to plants to a greater degree than the native NH4+
f, and soil microflora play an important role in the defixation process. The temporal changes in the content of recently fixed
NH4+ suggest that it is actively involved in N dynamics during a crop growth season. The amounts of NH4+ defixed during a growing season varied greatly within the groups of silty (20–200 kg NH4+-N ha−1 30 cm−1) as well as clayey (40–188 kg NH4+-N ha−1 30 cm−1) soils. The pool of recently fixed NH4+ may therefore be considered in fertilizer management programs for increasing N use efficiency and reducing N losses from
soils. 相似文献
466.
467.
The effects of residual sodium carbonate (RSC) in irrigation water on soil sodication and yield and cation composition of palmarosa (Cymbopogon martinii Roxb. Wats) and lemongrass (Cymbopogon flexuosus Steud Wats) were studied in the open bottom reinforced concrete cemented (RCC) cylindrical barrels embedded in the field and filled with sandy loam soils. The results indicated that the increasing RSC in irrigation water significantly increased the pH, electrolyte conductivity (ECe) and SARe of the soil and, hence, considerably decreased the herb and oil yield of both the palmarosa and lemongrass. The reduction in total herb yield was 14.5, 18.3, 28.8 and 32.0% in palmarosa and 38.6, 46.0, 57.7 and 62.6% in the lemongrass over control at 4.0, 8.0, 12.0 and 16.0 meq/l of RSC, respectively. The total oil yield of palmarosa increased by 22.6% with the increase in RSC from 2.0 (control) to 4.0 meq/l and further increase in RSC decreased the oil yield by 13.0, 22.4 and 22.9% over control at 8,12 and 16 meq/l of RSC, respectively. The total oil yield of lemongrass was decreased by 27.0, 39.4, 47.7 and 50.8% over control at 4, 8, 12 and 16 meq/l, respectively. The concentration of Na increased significantly and K and Ca decreased with increase in RSC of irrigation water in vegetative tissues of both species. The lemongrass accumulates significantly greater amount of Na in shoot tissues as compared to palmarosa and it failed to survive at high RSC after 21 months of transplanting. The results suggests that palmarosa is more tolerant to irrigation water sodicity than the lemongrass. 相似文献
468.
De Ankan Das Tapan Kumar Chand Karam Debnath Bikas Chandra Dey Saikat Hemadri Divakar Barman Nagendra Nath Chaudhary Jitendra Kumar Muthuchelvan Dhanavelu Saxena Arpit Tewari Neha Chauhan Ankita Lohumi Ankita Biswas Sanchay Kumar 《Tropical animal health and production》2019,51(1):261-265
Tropical Animal Health and Production - Bluetongue (BT) is a notifiable multiple species transboundary viral disease of domestic and wild ruminants. Though the disease is enzootic in India, little... 相似文献
469.
Pallavi Bhardwaj Pritam K. Sidhu Simrat Pal Singh Saini Dinesh M.B. Satyavan Rampal 《Journal of veterinary pharmacology and therapeutics》2019,42(4):430-439
The pharmacokinetics (PK) and pharmacodynamics (PD) of marbofloxacin (MBF) were determined in six healthy female goats of age 1.00–1.25 years after repeated administration of MBF. The MBF was administered intramuscularly (IM) at 2 mg kg?1 day?1 for 5 days. Plasma concentrations of MBF were determined by high‐performance liquid chromatography, and PK parameters were obtained using noncompartmental analysis. The MBF concentrations peaked at 1 hr, and peak concentration (Cmax) was 1.760 µg/ml on day 1 and 1.817 µg/ml on day 5. Repeated dosing of MBF caused no significant change in PK parameters except area under curve (AUC) between day 1 (AUC0–∞D1 = 7.67 ± 0.719 µg × hr/ml) and day 5 (AUC0‐∞D5 = 8.70 ± 0.857 µg × hr/ml). A slight difference in mean residence time between 1st and 5th day of administration and accumulation index (AI = 1.13 ± 0.017) suggested lack of drug accumulation following repeated IM administration up to 5 days. Minimum inhibitory concentration (MIC) demonstrated that Escherichia coli (MIC = 0.04 µg/ml) and Pasturella multocida (MIC = 0.05 µg/ml) were highly sensitive to MBF. Time‐kill kinetics demonstrated rapid and concentration‐dependent activity of MBF against these pathogens. PK/PD integration of data for E. coli and P. multocida, using efficacy indices: Cmax/MIC and AUC0–24hr/MIC, suggested that IM administration of MBF at a dose of 2 mg kg?1 day?1 is appropriate to treat infections caused by E. coli. However, a dose of 5 mg kg?1 day?1 is recommended to treat pneumonia caused by P. multocida in goats. The study indicated that MBF can be used repeatedly at dosage of 2 mg/kg in goats without risk of drug accumulation up to 5 days. 相似文献
470.