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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
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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
3.
Dynamics of cytokine gene expression in peripheral blood mononuclear cells of indigenous and exotic breeds of pigs in India 
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Improved HPLC method for the determination of curcumin,demethoxycurcumin, and bisdemethoxycurcumin 总被引：5，自引：0，他引：5
Jayaprakasha GK Jagan Mohan Rao L Sakariah KK 《Journal of agricultural and food chemistry》2002,50(13):3668-3672
Commercially available curcumin, a bright orange-yellow color pigment of turmeric, consists of a mixture of three curcuminoids, namely, curcumin, demethoxycurcumin, and bisdemethoxycurcumin. These were isolated by column chromatography and identified by spectroscopic studies. The purity of the curcuminoids was analyzed by an improved HPLC method. HPLC separation was performed on a C(18) column using three solvents, methanol, 2% AcOH, and acetonitrile, with detection at 425 nm. Four different commercially available varieties of turmeric, namely, Salem, Erode, Balasore, and local market samples, were analyzed to detect the percentage of these three curcuminoids. The percentages of curcumin, demethoxycurcumin, and bisdemethoxycurcumin as estimated using their calibration curves were found to be 1.06 +/- 0.061 to 5.65 +/- 0.040, 0.83 +/- 0.047 to 3.36 +/- 0.040, and 0.42 +/- 0.036 to 2.16 +/- 0.06, respectively, in four different samples. The total percentages of curcuminoids are 2.34 +/- 0.171 to 9.18 +/- 0.232%. 相似文献
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Nanocellulose reinforced PVA composite films: Effects of acid treatment and filler loading 总被引：1，自引：0，他引：1
Sun-Young Lee D. Jagan Mohan In-Aeh Kang Geum-Hyun Doh Soo Lee Seong Ok Han 《Fibers and Polymers》2009,10(1):77-82
Nanocellulose was prepared by acid hydrolysis of microcrystalline cellulose (MCC) at different hydrobromic acid (HBr) concentrations.
Polyvinyl alcohol (PVA) composite films were prepared by the reinforcement of nanocellulose into a PVA matrix at different
filler loading levels and subsequent film casting. Chemical characterization of nanocelluloses was performed for the analysis
of crystallinity (Xc), degree of polymerization (DP), and molecular weight (Mw). The mechanical and thermal properties of the nanocellulose reinforced PVA films were also measured for tensile strength
and thermogravimetric analysis (TGA). The acid hydrolysis decreased steadily the DP and Mw of MCC. The crystallinity of MCC with 1.5 M and 2.5 M HBr showed a significant increase due to the degradation of amorphous
domains in cellulose. Higher crystalline cellulose showed the higher thermal stability than MCC. From X-ray diffraction (XRD)
analysis, nanocellulose samples showed the higher peak intensity than MCC cases. Reduction of MCC particle by acid hydrolysis
was clearly observed from scanning electron microscope (SEM) images. The tensile and thermal properties of PVA composite films
were significantly improved with the increase of the nanocellulose loading. 相似文献
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Green teas were made by inactivating the enzymes present in fresh leaves of coarse/pruned (unused) and normal (used for tea) grades using different sources of thermal energies. Green teas were extracted in a Soxhlet using different solvents. The obtained miscella was subjected to concentration to give the extract. The extract was subjected to solvent-solvent extraction. Solvent extract was concentrated to obtain conserve. The yields of conserves are 17 +/- 0.8 and 15 +/- 0.8% from green teas of normal and coarse tea leaves, respectively. The radical scavenging activity of these extracts was evaluated using a DPPH in vitro model system. The total polyphenol content was also determined and found to be higher in conserves from normal tea leaves. However, radical scavenging activity of conserves from coarse and normal green tea leaves was found to be >90% at 15 ppm concentration. The HPLC profiles of these conserves were used to quantify the total catechin content with the help of calibration curves prepared using authentic samples at known concentrations. The total catechin content is found to be in the range of 55-85%. Results indicated that the extracts from coarse leaves also possess potential biological activity and could be used as nutraceuticals as well as for preservation purposes in food formulations. 相似文献
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P S Negi G K Jayaprakasha L Jagan Mohan Rao K K Sakariah 《Journal of agricultural and food chemistry》1999,47(10):4297-4300
Curcumin, the yellow color pigment of turmeric, is produced industrially from turmeric oleoresin. The mother liquor after isolation of curcumin from oleoresin contains approximately 40% oil. The oil was extracted from the mother liquor using hexane at 60 degrees C, and the hexane extract was separated into three fractions using silica gel column chromatography. These fractions were tested for antibacterial activity by pour plate method against Bacillus cereus, Bacillus coagulans, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Fraction II eluted with 5% ethyl acetate in hexane was found to be most active fraction. The turmeric oil, fraction I, and fraction II were analyzed by GC and GC-MS. ar-Turmerone, turmerone, and curlone were found to be the major compounds present in these fractions along with other oxygenated compounds. 相似文献
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Jayaprakasha GK Jagan Mohan Rao L Sakariah KK 《Journal of agricultural and food chemistry》2000,48(9):4294-4295
The steam-distilled oil of cinnamon (Cinnamomum zeylanicum) flowers was analyzed by GC and GC-MS. It consists of 23% hydrocarbons and 74% oxygenated compounds. A total of 26 compounds constituting approximately 97% of the oil were characterized. (E)-Cinnamyl acetate (41.98%), trans-alpha-bergamotene (7.97%), and caryophyllene oxide (7.2%) are found to be major compounds. This is the first report on the chemical composition of the flower oil of Cinnamomum zeylanicum. 相似文献
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To acquire the fertilizing competence, spermatozoa must undergo a cascade of physiological and biochemical changes collectively defined as capacitation. Compelling evidence signifies that the global increase in protein tyrosine phosphorylation is the driving factor for capacitation. In our laboratory, we previously demonstrated that nitric oxide (NO) induces capacitation in buffalo sperm and is associated with an increase in protein tyrosine phosphorylation. The aim of the present study is to identify the proteins undergo tyrosine phosphorylation during NO induced buffalo sperm capacitation using 2-D immunoblotting and mass spectrometry. The percentage of progressively motile and capacitated sperm was more in presence of l-arginine. Along with known tyrosine phosphoproteins like ATP synthase subunit beta, pyruvate dehydrogenase E1 component subunit beta, GST mu 3, F-actin capping protein subunit beta 2, GPD2 and VDAC2, interestingly novel tyrosine phosphoprotein substrates such as actin, serine/threonine-protein phosphatase PP1-gamma catalytic subunit, and glutamine synthetase were also identified which might be specific to the NO induced signaling and also emphasizes the species specificity with respect to tyrosine phosphorylation of proteins during capacitation. In conclusion, this study forms an essential step in delineating the proteins undergo tyrosine phosphorylation in response to NO induced signaling pathways during capacitation of buffalo sperm. 相似文献
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