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1.
M. Velhner G. Kozoderović E. Grego N. Galić I. Stojanov Z. Jelesić C. Kehrenberg 《Zoonoses and public health》2014,61(5):364-370
Quinolone‐resistant Salmonella Infantis (n = 64) isolated from human stool samples, food and poultry during the years 2006–2011 were analysed for their resistance phenotypes, macrorestriction patterns and molecular mechanisms of decreased susceptibility to fluoroquinolones. Minimum inhibitory concentrations (MICs) of nalidixic acid (NAL) and ciprofloxacin (CIP) were determined by the agar dilution procedure, and the susceptibility to additional antimicrobial agents was determined by the disc diffusion method. To assess the influence of enhanced efflux activity, MICs were determined in the presence and absence of the inhibitor PAβN. The results of pulsed‐field gel electrophoresis (PFGE) typing revealed that quinolone‐resistant S. Infantis in Serbia had similar or indistinguishable PFGE profiles, suggesting a clonal spread. All S. Infantis showed combined resistance to NAL and tetracycline, whereas multiple drug resistance to three or more antibiotic classes was rare (2 isolates of human origin). The MICs ranged between 512 and 1024 μg/mL for NAL and 0.125–2 μg/mL for CIP. A single‐point mutation in the gene gyrA leading to a Ser83→Tyr exchange was detected in all isolates, and a second exchange (Ser80→Arg) in the gene parC was only present in eight S. Infantis isolates exhibiting slightly higher MICs of CIP (2 μg/mL). The inhibitor PAβN decreased the MIC values of CIP by two dilution steps and of NAL by at minimum 3–6 dilution steps, indicating that enhanced efflux plays an important role in quinolone resistance in these isolates. The plasmid‐mediated genes qnr, aac(6′)‐lb‐cr and qepA were not detected by PCR assays. 相似文献
2.
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
3.
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
4.
Dynamics of cytokine gene expression in peripheral blood mononuclear cells of indigenous and exotic breeds of pigs in India 
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6.
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
7.
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
8.
Kogan LR Goldwaser G Stewart SM Schoenfeld-Tacher R 《Journal of the American Veterinary Medical Association》2008,232(10):1536-1542
OBJECTIVE: To gain a better understanding of sources and frequency of use of pet health information accessed by owners and assess the level of confidence in information accuracy as reported by pet owners who visit their veterinarians. DESIGN: Prospective study. SAMPLE POPULATION: 412 participants from 17 small animal veterinary clinics. PROCEDURES: Questionnaires pertaining to pet owners' habits related to pet health information (sources and frequency of their use and confidence in accuracy of information accessed) were distributed by front desk staff at 17 participating veterinary clinics. A cover letter was included with each survey that offered instructions for completion and assured respondents of their anonymity. All completed surveys were placed in an envelope and returned to the researchers for analysis. RESULTS: Results indicated that pet owners who visited their veterinarians acquired pet information from veterinarians via the telephone or in person and from family or friends more frequently than they acquired such information from the World Wide Web. Pet owners also reported more confidence in information received from veterinarians (in person and via telephone conversations), compared with information from any other accessible source. CONCLUSIONS AND CLINICAL RELEVANCE: The use of Web sites by owners as sources of pet health information will undoubtedly continue to grow. Veterinarians can play a more proactive role in helping pet owners to access reliable Web sites that provide useful pet health information, thereby providing a benefit to all parties. 相似文献
9.
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
10.
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