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排序方式: 共有971条查询结果,搜索用时 15 毫秒
961.
Abayeh OJ Abdulrazaq AK Olaogun R 《Plant foods for human nutrition (Dordrecht, Netherlands)》1999,54(1):43-48
The oil content and quality characteristics of Canarium schweinfurthii Engl. oil are described. The oils were extracted from the mesocarp and endocarp using hexane to remove the free flowing lipid (FFL) and successive extraction with CHCl3-MeOH followed by water saturated butanol to remove bound lipid (BL). On a dry matter basis, the mesocarp contained 68.3% FFL and 13.7% BL while the endocarp contained 67.0% FFL and 13.0% BL. The quality characteristics of the mesocarp oil extracts were 151.9–195.3 mg KOH/g fat saponification value (SV), 20–40 mEq peroxide/kg fat peroxide value (PV), 71.1–94.9 g iodine/100 g fat iodine value (IV) and 1.33–8.30 mg KOH acid value (AV). Characteristics for the endocarp oil extracts were 95.4–184.3 mg KOH/g fat SV, 4.0–8.0 mEq peroxide/kg fat PV, 100.1–118.3 g iodine/100 g fat IV, and AV of 0.48–8.70 mg KOH. The fatty acid composition of the first hexane extracts indicated that the oils were primarily C16 and C18s. The mesocarp contained 31.7% hexadecanoic acid, 30.0% 9-octadecenoic acid, 30.1% 6,9-octadecadienoic acid and 8.2% 9,12,15-octadecatrienoic acid, while the endocarp, contained 31.2% hexadecanoic acid, 28.9% 9-octadecenoic acid and 31.3% 6,9-octadecadienoic acid. 相似文献
962.
Anisuzzaman AK Storehalder T Williams DC Ogg N Kilbourne TD Johnsamuel J Cottrell CE 《Journal of agricultural and food chemistry》2008,56(2):502-506
Both primary and secondary alcohols degrade iprodione, 3-(3,5-dichlorophenyl)-N-(1-methylethyl)-2,4-dioxo-1-imidazolidine carboxamide. Steric hindrance has been found to have an inverse effect on the rate of its decomposition, and a fully substituted alcohol, such as tert-butanol, does not degrade iprodione due to extreme steric hindrance. The instability of iprodione in alcohol was found to be a function of the structure of the alcohol. The product, N-(3,5-dichlorophenyl)-3-(1-methylethyl)-2,4-dioxo-1-imidazolidine carboxamide, is obtained from all of the reacting alcohols. Confirmation of this structure came from the consideration of its NMR, mass spectral, and elemental analysis data. 相似文献
963.
Sharma UK Sharma K Sharma N Sharma A Singh HP Sinha AK 《Journal of agricultural and food chemistry》2008,56(2):374-379
The outcome of different extraction procedures (microwave, ultrasound, Soxhlet, and maceration) on the antioxidant activity of seeds, leaves, pulp, and fruits of Hippophae rhamnoides (sea buckthorn or SBT) was investigated by two different bioassays: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. The SBT extracts were found to possess strong antioxidant activity measured in terms of TEAC (2.03-182.13 and 6.97-282.75 mg/g) with ABTS and DPPH assays, respectively. In general, the antioxidant capacity of microwave-assisted extracts was found to be significantly higher than those obtained by ultrasound-assisted extraction (UAE) and maceration while being slightly higher than Soxhlet extracts. Further, microwave extracts of seeds were found to possess maximum antioxidant capacity followed by leaves, fruits, and pulp. Also, the chemical composition of extracts, studied in terms of the total phenolic content, was found to be in the range of 1.9-23.5 mg/g Gallic acid equivalent (GAE), which indicates a strong correlation between antioxidant activity and phenolic content present in the SBT. In addition, some of its bioactive phenolic constituents, such as rutin ( 1), quercetin-3- O-galactoside ( 2), quercetin ( 3), myricetin ( 4), kaempferol ( 5), and isorhamnetin ( 6), were also quantified in different extracts by reverse-phase high-performance liquid chromatography (RP-HPLC). 相似文献
964.
Taheri-Kafrani A Bordbar AK Mousavi SH Haertlé T 《Journal of agricultural and food chemistry》2008,56(16):7528-7534
Bovine beta-lactoglobulin (beta-LG) in vivo (in milks) has been found in complexes with lipids such as butyric and oleic acids. To elucidate the still unknown structure-function relationship in this protein, the structural changes of beta-lactoglobulin variant A (beta-LG A) in the presence of anionic surfactant such as sodium n-dodecyl sulfate (SDS) and in the presence of nonionic surfactant such as Triton X-100 have been investigated. Subsequently, the retinol binding by beta-LG has been investigated in the presence of various amounts of these surfactants as its binding indicator. The results of UV-vis and fluorescence studies show a higher denaturating effect of SDS at acid pH that can be due to greater positive charges of beta-LG at this pH indicating also the nonspecific hydrophobic interactions of Triton X-100 with beta-LG at all studied pHs. Isothermal titration calorimetry (ITC) measurements indicate the endothermic nature of beta-LG/SDS interactions and the exothermic nature of Triton X-100/beta-LG interactions. The analysis of the binding data demonstrates the absence of considerable changes in retinol binding properties of beta-LG in the presence of various amounts of these surfactants. This implies that surfactant binding does not change the conformation of beta-LG in the regions defining the retinol-binding site. 相似文献
965.
Fulcher RP Ludwig LL Bergman PJ Newman SJ Simpson AM Patnaik AK 《Journal of the American Veterinary Medical Association》2006,228(2):210-215
OBJECTIVE: To evaluate completeness of excision and clinical outcome in dogs with cutaneous mast cell tumors (MCTs) excised with a lateral margin of 2 cm and a deep margin of 1 fascial plane. DESIGN: Prospective study. ANIMALS: 16 client-owned dogs with 1 or more cutaneous MCTs. PROCEDURE: Excision of MCTs was performed with a 2-cm lateral margin and a deep margin of 1 fascial plane. Histologic tumor grading was performed; surgical margins were categorized as complete or incomplete. Follow-up information was obtained via repeat examination of the dogs by veterinarians or client-completed questionnaires. RESULTS: 4 grade I and 19 grade II cutaneous MCTs were evaluated. Overall, 21 (91%) MCTs were completely excised; 2 grade II tumors had foci of mast cells at the 2-cm margin. Two dogs received adjunctive treatments following surgery. Follow-up information was available for all dogs (median follow-up period, 379 days; range, 51 to 538 days); no local recurrence was detected during this time. De novo MCTs were detected in 3 of 16 dogs at 37, 54, and 154 days after surgery. Via Kaplan-Meier analysis, median survival time and disease-free interval were both > 538 days (medians not yet reached). No prognostic variables were identified. CONCLUSIONS AND CLINICAL RELEVANCE: Excision with a 2-cm lateral margin and a deep margin of 1 fascial plane may result in satisfactory excision of grades I and II MCTs in dogs, with recurrence rates similar to those reported previously. Use of these margins may minimize complications associated with larger local tumor resection. 相似文献
966.
Raekallio MR Hielm-Björkman AK Kejonen J Salonen HM Sankari SM 《Journal of the American Veterinary Medical Association》2006,228(6):876-880
OBJECTIVE: To evaluate the adverse effects of carprofen in dogs after oral administration for 2 months. DESIGN: Prospective, randomized, blinded, placebo-controlled clinical trial. ANIMALS: 22 dogs with osteoarthritis in the hip or elbow joint. PROCEDURE: 13 dogs received orally administered carprofen daily for 2 months, and 9 dogs received a placebo for 2 months. Dogs were weighed, and serum and urine samples were collected before initiation of treatment and 4 and 8 weeks after initiation of treatment. Serum concentrations of total protein, albumin, urea, and creatinine and serum activities of alkaline phosphatase (ALP) and alanine aminotransferase (ALT) were measured. Urinary ALP-to-creatinine, gamma-glutamyltransferase (GGT)-to-creatinine, and protein-to-creatinine ratios were calculated. Dogs were observed by owners for adverse effects. RESULTS: Serum protein and albumin concentrations were lower in treated dogs than in those that received placebo at 4 weeks, but not at 8 weeks. No changes were observed in serum urea or creatinine concentrations; ALP or ALT activity; or urinary ALP-to-creatinine, GGT-to-creatinine, or protein-to-creatinine ratios. Dogs' weights did not change. Severity of vomiting, diarrhea, and skin reactions did not differ between groups, but appetite was better in dogs receiving carprofen than in dogs in the placebo group. CONCLUSIONS AND CLINICAL RELEVANCE: It is possible that the transient decreases in serum protein and albumin concentrations in dogs that received carprofen were caused by altered mucosal permeability of the gastrointestinal tract because no indications of renal or hepatic toxicity were observed. Carprofen appeared to be well tolerated by dogs after 2 months of administration. 相似文献
967.
Bansiwal AK Rayalu SS Labhasetwar NK Juwarkar AA Devotta S 《Journal of agricultural and food chemistry》2006,54(13):4773-4779
The feasibility of using surfactant-modified zeolite (SMZ) as a carrier for fertilizer and for slow release of phosphorus (P) was investigated. Zeolite-A was modified by using hexadecyltrimethylammonium bromide, a cationic surfactant, to modify its surface to increase its capacity to retain anion, namely, phosphate (PO4(3-)). SMZ was thoroughly characterized using X-ray diffraction, Fourier transform infrared, and scanning electron microscopy to study the effect of surfactant modification. Zeolite-A and SMZ were then subjected to P loading by treating them with fertilizer (KH2PO4). It was observed that the P loading on SMZ increased by a factor of 4.9 as compared to the unmodified zeolite-A. A comparative study of the release of P from fertilizer-loaded unmodified zeolite-A and SMZ and from solid KH2PO4 was performed using the constant flow percolation reactor. The results show that the P supply from fertilizer-loaded SMZ was available even after 1080 h of continuous percolation, whereas P from KH2PO4 was exhausted within 264 h. The results indicate that SMZ is a good sorbent for PO4(3-), and a slow release of P was achievable. These properties suggest that SMZ has a great potential as the fertilizer carrier for slow release of P. 相似文献
968.
Pinelo M Landbo AK Vikbjerg AF Meyer AS 《Journal of agricultural and food chemistry》2006,54(18):6564-6571
This study examined the phenolic composition and the antioxidant potencies of black currant juices that had been experimentally clarified with acidic proteases and pectinases to retain the phenolics and which had been subjected to rat intestinal mucosa extract incubation to mimic gut cell mediated biotransformation of phenolics. When compared at equimolar levels of 2.5 microM gallic acid equivalents, the black currant juice samples prolonged the induction time of human low-density lipoprotein oxidation in vitro by 2.6-3.6 times, and the order of antioxidant potency of differently clarified black currant juices was centrifuged juice > gelatin silica sol clarified juice > enzymatically clarified juice approximately raw juice. No immediate relationship between the, almost similar, phenolic profiles of the juice samples and their relative antioxidant activities could be established. Incubation of juices with a rat small intestine cell extract for 19 h promoted significant decreases in the contents of the anthocyanin 3-O-beta-glucosides (cyanidin 3-O-beta-glucoside and delphinidin 3-O-beta-glucoside), but did not affect the anthocyanin 3-O-beta-rutinosides (cyanidin 3-O-beta-rutinoside and delphinidin 3-O-beta-rutinoside) of the black currant juice. Black currant juice samples subjected to such intestinal cell extract incubation had approximately 30% decreased antioxidant capacity. Incubation of juices with the rat small intestine cell extracts at neutral pH appeared to decrease the levels of delphinidin glucosides more than the levels of cyanidin glucosides. The results provide an explanation for the predominant detection of anthocyanin rutinosides, and not anthocyanin glucosides, in plasma and urine in in vivo studies and provide important clues to better understand the complex mechanisms affecting dietary phenols in the gut. 相似文献
969.
The heartbeat of the Oligocene climate system 总被引:2,自引:0,他引:2
Pälike H Norris RD Herrle JO Wilson PA Coxall HK Lear CH Shackleton NJ Tripati AK Wade BS 《Science (New York, N.Y.)》2006,314(5807):1894-1898
A 13-million-year continuous record of Oligocene climate from the equatorial Pacific reveals a pronounced "heartbeat" in the global carbon cycle and periodicity of glaciations. This heartbeat consists of 405,000-, 127,000-, and 96,000-year eccentricity cycles and 1.2-million-year obliquity cycles in periodically recurring glacial and carbon cycle events. That climate system response to intricate orbital variations suggests a fundamental interaction of the carbon cycle, solar forcing, and glacial events. Box modeling shows that the interaction of the carbon cycle and solar forcing modulates deep ocean acidity as well as the production and burial of global biomass. The pronounced 405,000-year eccentricity cycle is amplified by the long residence time of carbon in the oceans. 相似文献
970.