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141.
Syed Laik Ali 《Analytical and bioanalytical chemistry》1972,262(4):278-282
The different aspects of Vitamin D3 determination and the data reported in the literature are discussed. The spectrophotometric determination of Vitamin D3 in cod-liver oil is carried out after the alkaline saponification, extraction of unsaponified parts, precipitation of accompanying sterols and the column- and thin-layer chromatographic purification and separation of vitamin D3 on 40 cm plates from other vitamins. The dyestuff α-naphtholbenzein is suited well as standard substance for the better location and identification of vitamin D3 zone on the thin-layer plate. The results obtained from the chemical method were checked through the simultaneous biological determination. 相似文献
142.
The present study was aimed to investigate the variation of stable isotopic ratios of carbon, nitrogen, hydrogen, and oxygen in wheat kernel along with different processed fractions from three geographical origins across 5 years using isotope ratio mass spectrometry (IRMS). Multiway ANOVA revealed significant differences among region, harvest year, processing, and their interactions for all isotopes. The region contributed the major variability in the δ13C ‰, δ2H ‰, δ15N ‰, and δ18O‰ values of wheat. Variation of δ13C ‰, δ15N ‰, and δ18O ‰ between wheat whole kernel and its products (break, reduction, noodles, and cooked noodles) were ?0.7‰, and no significant difference was observed, suggesting the reliability of these isotope fingerprints in geographical traceability of wheat‐processed fractions and foods. A significant influence of wheat processing was observed for δ2H values. By applying linear discriminant analysis (LDA) to the whole dataset, the generated model correctly classified over 91% of the samples according to the geographical origin. The application of these parameters will assist in the development of an analytical control procedure that can be utilized to control the mislabeling regarding geographical origin of wheat kernel and its products. 相似文献
143.
Saira Hussain Ata ur Rehman David J. Luckett Syed Muhammad Saqlan Naqvi Christopher L. Blanchard 《Molecules (Basel, Switzerland)》2021,26(7)
Valorization of vegetable oil waste residues is gaining importance due to their high protein and polyphenol contents. Protease inhibitors (PIs), proteins from these abundantly available waste residues, have recently gained importance in treating chronic diseases. This research aimed to use canola meal of genetically diverse Brassica napus genotypes, BLN-3347 and Rivette, to identify PIs with diverse functionalities in therapeutic and pharmacological applications. The canola meal PI purification steps involved: native PAGE and trypsin inhibition activity, followed by ammonium sulfate fractionation, anion exchange, gel filtration, and reverse-phase chromatography. The purified PI preparations were characterized using SDS-PAGE, isoelectric focusing (IEF), and N terminal sequencing. SDS-PAGE analysis of PI preparations under native reducing and nonreducing conditions revealed three polymorphic PIs in each genotype. The corresponding IEF of the genotype BLN-3347, exhibited three acidic isoforms with isoelectric points (pI) of 4.6, 4.0, and 3.9, while Rivette possessed three isoforms, exhibiting two basic forms of pI 8.65 and 9.9, and one acidic of pI 6.55. Purified PI preparations from both the genotypes displayed dipeptidyl peptidase-IV (DPP-IV) and angiotensin-converting enzyme (ACE) inhibition activities; the BLN-3347 PI preparation exhibited a strong inhibitory effect with lower IC50 values (DPP-IV 37.42 µg/mL; ACE 129 µg/mL) than that from Rivette (DPP-IV 67.97 µg/mL; ACE 376.2 µg/mL). In addition to potential human therapy, these highly polymorphic PIs, which can inhibit damaging serine proteases secreted by canola plant pathogens, have the potential to be used by canola plant breeders to seek qualitative trait locus (QTLs) linked to genes conferring resistance to canola diseases. 相似文献
144.
Misbahul Ain Khan Alice Maria Coimbra Rolim Antonio Elydio Guaroni 《Journal of heterocyclic chemistry》1983,20(2):475-476
The synthesis of the parent ring system and some of the derivatives of 1H-pyrazolo[3,4-d]thieno[2,3-b]pyridine are described. 相似文献
145.
The effects of exit-wedge angle on evolution, formation, pinch-off, propagation and diffusive mass entrainment of vortex rings
in air were studied using digital particle image velocimetry. Vortex rings were generated by passing a solenoid-valve-controlled
air jet through a cylindrical nozzle. Experiments were performed over a wide range of exit-wedge angles (10° ≤ α ≤ 90°) of the cylindrical nozzle, initial Reynolds numbers (450 ≤ Re ≤ 4,580) and length-to-diameter ratios (0.9 ≤ L/D ≤ 11) of the air jet. For sharp edges (α ≤ 10°), a secondary ring may emerge at high Reynolds numbers, which tended to distort the vortex ring if ingested into it.
For blunt edges (α ≥ 45°), by contrast, stable vortex rings were produced. The formation phase of a vortex ring was found to be closely related
to its evolution pattern. An exit-wedge angle of 45° was found to be optimal for rapid pinch-off and faster propagation and
better stability of a vortex ring. Diffusive mass entrainment was found to be between 35% and 40% in the early stages of a
vortex ring propagation and it gradually increased throughout the course of vortex ring propagation. Entrainment fraction
was found to be sensitive to the L/D ratio of the initial jet and decreases when the L/D ratio is increased. 相似文献
146.
Kishore Kumar Anantoju Thirumala Chary Maringanti Baquer Syed Mohd. 《Tetrahedron letters》2018,59(30):2938-2940
Total synthesis of modified pentapeptide, caldoramide, a cytotoxic linear pentapeptide from the marine cyanobacterium Caldora penicillate is described. Notable features of the route include the efficient preparation of three key fragments and final assembly to the natural product via sequential amide couplings. The spectral data of the synthetic compound was found to be in comparison with that of the isolated natural product. 相似文献
147.
The quality of colour changes of the indicators hematoxylin, 4(2-pyridylazo)resorcinol (PAR), xylenol orange, pyrocatechol violet, chromazurolS and eriochrome cyanineR in the complexometric titration of copper(II) with ethylenediaminetetraacetic acid (EDTA) were studied with the help of tristimulus colorimetry, utilising a comparative study of the parameters SCD (specific colour discrimination), CIE La*b* 1976 and LABHNU 1977. Hematoxylin was found to be the best indicator among those studied. A screened indicator, viz. PAR + malachite green (52), was developed to enhance the quality of colour transition at the end-point and the accuracy of the titrimetric determination. 相似文献
148.
AbstractThe whole plant, Tricholepis chaetolepis, powder was investigated using proximate and fluorescence analysis along with determining the extractive values. Total phenolics, flavonoids and total protein contents of n-hexane, chloroform and methanolic extracts of the whole plant were also determined. The anti-diabetic activity of all the three extracts of the plant was determined by in vitro alpha-amylase inhibition assay. The anti-oxidant potential was evaluated using Phosophomolybdenum and DPPH methods. The anti-inflammatory potential of all extracts were determined by carrageenan-induced rat paw oedema model. The evaluation of the plant extracts exhibited the anti-diabetic, anti-oxidant, and anti-inflammatory activities in dose dependent fashion. The research concludes that Tricholepis chaetolepis extracts contain phenol, flavonoids, and tannins that show observable anti-oxidant and anti-diabetic potential. It is also concluded that the methanol extract of the plant showed the maximum effect against inflammation induced by carrageenan in rat paw oedema as compared with n-hexane and chloroform extracts. 相似文献
149.
A closed-form expression is presented to find the location of solid-liquid interface motion in convection-dominated solidification and melting problems. In this regard, the solutions are expressed in terms of the generalized representations of error functions,E (u, v) andF (u, v), which are useful to heat-conduction problems with convective-type boundary conditions. It is demonstrated that for constant surface temperature, the interface solution reduces to the classical Neumann solution. 相似文献
150.
Inam ul Haq Raja Jae Yeol Lee In Tae Kim So Ha Lee 《Monatshefte für Chemie / Chemical Monthly》2008,139(7):725-737
Much effort has been devoted to the design and synthesis of polymers for use in flat panel display, solid state lighting,
transistors, and photovoltaic devices. Especially, development of white light emitting polymeric materials has recently attracted
much interest owing to their possible use in lighting application and backlights for flat panel displays. White emission has
been obtained from polymeric molecules, small organic molecules, organometallic molecules, and phosphor-based or quantum dot-based
inorganic molecules. Among materials used in white light emitting diodes, we summarize the white light emitting polymeric
materials synthesized and published till December 2007.
Correspondence: In Tae Kim, Department of Chemistry, Kwangwoon University, 447-1 Wolgye-Dong, Nowon-Ku, Seoul 139-701, Korea,
So Ha Lee, Life Sciences Research Division, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650,
Korea. 相似文献