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151.
152.
Paramashivappa R Kumar PP Vithayathil PJ Rao AS 《Journal of agricultural and food chemistry》2001,49(5):2548-2551
Commercially available cashew (Anacardium occidentale L.) nut shell liquid (CNSL) mainly contains the phenolic constituents anacardic acid, cardol, and cardanol. These phenolic constituents are themselves heterogeneous, and each of them contains saturated, monoene, diene, and trienes in the fifteen-carbon side chain. This communication describes the separation of anacardic acid, cardol, and cardanol for industrial application. Anacardic acid was selectively isolated as calcium anacardate. The acid-free CNSL was treated with liquor ammonia and extracted with hexane/ethyl acetate (98:2) to separate the mono phenolic component, cardanol. Subsequently, ammonia solution was extracted with ethyl acetate/hexane (80:20) to obtain cardol. 相似文献
153.
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
154.
The effect of surface growth of blue-green algae and bryophytes on some microbiological,biochemical, and physical soil properties 总被引:3,自引:0,他引:3
Summary The influence of surface growth of inoculated cyanobacteria (blue-green algae) on subsurface properties of a brown earth, silt loam soil was studied in reconstituted flooded soil columns. One blue-green algae species, Nostoc muscorum, become dominant within the first 7 days of inoculation. In light control columns (not inoculated) a bryophyte, Barbula recurvirostra, was dominant although significant growth of indigenous blue-green algae occurred. The blue-green algae counts were in the range of 1×106 g-1 dry soil in the surface layer (0–0.7 cm) in both columns. Any effect of surface phototrophic growth on soil properties was restricted to the surface layer. In inoculated columns there was a twofold increase in microbial biomass and an eightfold increase in bacterial numbers by week 13. However, bacterial numbers declined so that there was only a 2.8-fold increase by week 21. Dehydrogenase (x2.1), urease (x2.8) and phosphatase (x3.1) activities and polysaccharides (+69%) increased by week 21 as a result of the blue-green algae inoculation along with a significant improvement in soil aggregation. However, similar increases occurred in the light control columns, indicating that given appropriate conditions of light and moisture indigenous species may be ultimately as effective as introduced species in bringing about biochemical and microbiological changes to soil. 相似文献
155.
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
156.
The lethal concentrations (LC50 96 h?1) were measured experimentally by exposing the earthworms (Lampito mauritii) in moist vermiculite and in water. The morphological changes observed during the exposure of animals to the monocrotophos and dichlorvos were outlined. The mortality rate was higher in the water medium than in moist vermiculite. The hyperactivity at low pesticide concentrations is found to influence the size of the population. 相似文献
157.
Paramashivappa R Phani Kumar P Subba Rao PV Srinivasa Rao A 《Journal of agricultural and food chemistry》2002,50(26):7709-7713
Anacardic acid (6-pentadecylsalicylic acid), a major component of cashew nut shell liquid, consists of a heterogeneous mixture of monoenes, dienes, and trienes. The enes mixture of anacardic acid was hydrogenated to a saturated compound. Using saturated anacardic acid as a starting material, analogues of sildenafil [a potent phosphodiesterase-5 (PDE(5)) inhibitor and an orally active drug for the treatment of erectile dysfunction] were synthesized, to observe the effect of the pentadecyl side chain on PDE(5) inhibition. The synthesized compounds were characterized by spectral studies and tested for PDE(5) inhibition, and the results were compared with those obtained with sildenafil. 相似文献
158.
159.
A.G. Pillai Medha S. Naik G.A. Momin P.S.P. Rao P.D. Safai K. Ali Henning Rodhe Lennart Granat 《Water, air, and soil pollution》2001,130(1-4):475-480
Rain water and dustfall deposition samples were collected at Pune, an urban site (1992–98) and at Sinhagad, a rural site (1992–94). The samples were collected with wet-only and bulk collectors at Pune and with bulk collector at Sinhagad. The samples were analyzed for major ions, pH and conductivity. The study showed that the rain water at both places is alkaline (pH > 5.6). The average pH at Pune was 6.1. Neutralising components, indicated by Ca and non sea salt (nss) Mg have higher concentrations than the acidifying components SO4 and NO3. The wet deposition fluxes of all the ionic components were higher than the dustfall fluxes. Relative contribution from dustfall was largest for K, Ca, Mg and NO3. Dustfall was greater at Pune, compared to Sinhagad for all components and up to double for Ca. 相似文献
160.
Topsoils affected by surface mining suffer severe physical degradation and lose most of their earthworm populations. After mining, replaced soils are planted to grassland and managed to improve soil structure. Earthworm inoculation into selected restored areas produced populations similar to those of undisturbed soils within 3 years. Soil properties in inoculated areas were compared with those of controls to evaluate the contribution of casts to bulk soil aggregation, and soil organic matter and root content responses to earthworm activity. Crumb porosity and coarse particle content were measured in water-stable macro-aggregates and earthworm casts to establish whether aggregates were formed by earthworms. Over a 5- to 6-year period, inoculation increased stable aggregation (>2 μm, >60 μm and >3 mm), even at 0- to 5-cm depth where it reduced soil organic matter content. Productivity and root content were also increased by inoculation; roots and organic matter were re-distributed to greater depth. Crumb porosity decreased with casts > aggregates (inoculated plots) > aggregates (control plots). Coarse particle content increased with casts < aggregates (inoculated plots) < aggregates (control plots). Coarse particle and porosity data were consistent with much of the newly aggregated soil being processed and formed by earthworms as casts. Whilst levels of soil organic matter were often closely associated with percentage stable aggregation, root content showed weaker associations. Aggregation percentage was most closely associated with abundance of Aporrectodea longa , although at particular depths significant correlations were also obtained for Aporrectodea caliginosa and Lumbricus terrestris . Results suggest that earthworms, rather than plant roots, initiate aggregation in severely degraded grassland soils. 相似文献