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排序方式: 共有189条查询结果,搜索用时 156 毫秒
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NEDJOUA CHEGHIB MOHAMED ABDAOUI THIERRY CRESTEIL GENEVIÈVE AUBERT JEAN-LOUIS KRAUS 《Polycyclic Aromatic Compounds》2013,33(3):143-153
Through the coupling of substituted benzaldehydes with 8-hydroxy 5-amino methyl quinoline scaffold, a series of new derivatives has been synthesized. In vitro growth inhibitory effects on cancer cell line model have been evaluated. Discussion on the chemical reactivity of these new polycyclic aromatic analogs to generate alkylating species led to the hypothesis that the presence of an imine moiety impedes the formation of quinone methide intermediate and consequently abolishes in part their antiproliferative activity. 相似文献
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MOHAMED T. EWEIDA ZAKARIA A. NOFAL MOHAMED A. RIZK MOSTAFA A. NOFAL 《Journal of food science》1982,47(5):1732-1733
The quality of two new drought-resistant varieties of rice (IR441 and IR3304) grown in Egypt, were compared with three commercial varieties (Selection 180, Reiho and Giza 172). Based on milling yield, IR441 and IR3304 showed lowest rice quality. Gelatinization temperature was highest in IR441 and lowest in IR3304 and Giza 172. During cooking, water uptake ratio and elongation ratio were higher in IR441 and Selection 180. Protein content was in the range 4–6% for all varieties. Amino acid analysis indicated nutritional superiority of Selection 180 over the other varieties. With the exception of lysine and threonine, the amount of each of the other essential acids in IR441 and Reiho matched or exceeded the FAO/ WHO pattern. IR3304 is deficient in the most number of essential acids (lysine, threonine, and isoleucine). 相似文献
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N. A. EISSA A. A. BAHGAT A. H. MOHAMED S. A. SALEH 《Journal of the American Ceramic Society》1976,59(7-8):327-329
Activation energies for the formation of Zn, Cd, and Ni ferrites were calculated from a series of Moessbauer spectra obtained during the formation process. These spectra were analyzed by 3 methods. The results showed that the Moessbauer effect can be used to follow the reaction kinetics. 相似文献
27.
IBTISSEM HAMROUNI-SELLAMI MOHAMED ELYES KCHOUK BRAHIM MARZOUK 《Journal of Food Biochemistry》2008,32(3):335-352
The chemical composition of Tunisian Nigella sativa L. seeds was investigated. The results showed that linoleic acid (C18:2) was the major fatty acid with 65.1% of total fatty acids (TFAs) followed by oleic acid (C18:1) with 12.7% of TFAs. Neutral lipids (NLs) were mainly composed of triacylglycerols with 98.4% of total NLs. Polar lipids were mainly composed of phosphatidylcholine as the major phospholipid subclass, whereas digalactosyldiacylglycerol was the major galactolipid. Total sterols (TSs) represented 2.2% of the fixed oil and were composed of (-sitosterol as the major sterol representing 60.2% of the TSs. The results indicated that the sterols were mainly present in the esterified and in the free forms with 51.2 and 36.1%, respectively, of TS content. Finally, the aroma composition of the volatile oil from oleoresin exhibited the presence of many bioactive compounds such as p-cymene as the major component followed by ocimene, α -thujene, octen-3-ol with appreciable rates of 1,8-cineole and thymol.
The results obtained showed that Nigella sativa L. seeds were a good source of polyunsaturated fatty acids (PUFAs), phytosterols (PSs) and phospholipids (PhLs) for the human diet. These seeds could be used by the food industry for formulating functional foods enriched with PUFAs and PSs. For pharmaceutical applications, N. sativa L. conjugated sterols could be used as precursors for the hemisynthesis of many hydrosoluble steroids. Also, N. sativa L. seeds are a good source of PhLs and aroma compounds, and therefore, they could be utilized in biscuit manufacturing and in food flavoring. The presence of many bioactive compounds in N. sativa L. essential oil (p-cymene, limonene, α-pinene, linalool and thymol), known for their powerful antimicrobial function, could support the utilization of the essential oil bactericidal agents. 相似文献
PRACTICAL APPLICATIONS
The results obtained showed that Nigella sativa L. seeds were a good source of polyunsaturated fatty acids (PUFAs), phytosterols (PSs) and phospholipids (PhLs) for the human diet. These seeds could be used by the food industry for formulating functional foods enriched with PUFAs and PSs. For pharmaceutical applications, N. sativa L. conjugated sterols could be used as precursors for the hemisynthesis of many hydrosoluble steroids. Also, N. sativa L. seeds are a good source of PhLs and aroma compounds, and therefore, they could be utilized in biscuit manufacturing and in food flavoring. The presence of many bioactive compounds in N. sativa L. essential oil (p-cymene, limonene, α-pinene, linalool and thymol), known for their powerful antimicrobial function, could support the utilization of the essential oil bactericidal agents. 相似文献
28.
JAVARIA AFZAL XIUKANG WANG MUHAMMAD HAMZAH SALEEM XUECHENG SUN SHAHID HUSSAIN IMRAN KHAN MUHAMMAD SHOAIB RANA SHAKEEL AHMED SAMRAH AFZAL AWAN SAJID FIAZ OMAR AZIZ KASHIF ALI KUBAR SHAFAQAT ALI CHENGXIAO HU 《Biocell》2021,45(6):1631-1649
Soil contamination with toxic heavy metals [such as cadmium (Cd)] is becoming a serious global problem due
to rapid development of social economy. Iron (Fe), being an important element, has been found effective in enhancing
plant tolerance against biotic and abiotic stresses. The present study investigated the extent to which different levels of
Ferrous sulphate (FeSO4) modulated the Cd tolerance of rice (Oryza sativa L.), when maintained in artificially Cd
spiked regimes. A pot experiment was conducted under controlled conditions for 146 days, by using natural soil,
mixed with different levels of CdCl2 [0 (no Cd), 0.5 and 1 mg/kg] together with the exogenous application of FeSO4
at [0 (no Fe), 1.5 and 3 mg/kg] levels to monitor different growth, gaseous exchange characteristics, oxidative stress,
antioxidative responses, minerals accumulation, organic acid exudation patterns of O. sativa. Our results depicted that
addition of Cd to the soil significantly (P < 0.05) decreased plant growth and biomass, gaseous exchange parameters,
mineral uptake by the plants, sugars (soluble, reducing, and non-reducing sugar) and altered the ultrastructure of
chloroplasts, plastoglobuli, mitochondria, and many other cellular organelles in Cd-stressed O. sativa compared to
those plants which were grown without the addition of Cd in the soil. However, Cd toxicity boosted the production of
reactive oxygen species (ROS) by increasing the contents of malondialdehyde (MDA), which is the indication of
oxidative stress in O. sativa and was also manifested by hydrogen peroxide (H2O2) contents and electrolyte leakage to
the membrane bounded organelles. Although, activities of various antioxidative enzymes like superoxidase dismutase
(SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) and non-enzymatic antioxidants like
phenolics, flavonoid, ascorbic acid, anthocyanin and proline contents increased up to a Cd level of 0.5 mg/kg in the
soil but were significantly diminished at the highest Cd level of 1 mg/kg in the soil compared to those plants which
were grown without the addition of Cd in the soil. The negative impacts of Cd injury were reduced by the application
of FeSO4 which increased plant growth and biomass, improved photosynthetic apparatus, antioxidant enzymes, minerals uptake together with diminished exudation of organic acids as well as oxidative stress indicators in roots and
shoots of O. sativa by decreasing Cd retention in different plant parts. These results shed light on the effectiveness of
FeSO4 in improving the growth and upregulation of antioxidant enzyme activities of O. sativa in response to Cd
stress. However, further studies at field levels are required to explore the mechanisms of FeSO4-mediated reduction of
the toxicity of not only Cd, but possibly also other heavy metals in plants. 相似文献
29.
This work presents a theoretical study of two coherent schemes which allow the manipulation of wave packets created in atomic systems by strong ultrashort pulses. Our three-state system is composed of a ground state and two excited states simultaneously excited by the laser pulses. The corresponding dynamics are described in the bright state-dark state formalism where spectacular effects appear. (1) The wave packet created initially by a first pulse can be completely frozen through the action of a second strong pulse. (2) For pulses with a generalized pulse area equal to (2 p +1)2π (p integer), the population is preferentially transferred from the ground state to the dark state whatever the pulse duration. This is in complete disagreement with the physical interpretation valid in the weak field regime where the wave packet created by an ultrashort pulse is localized in the bright state at the end of the pulse. This effect can be revealed with wave packet interference induced by a second identical pulse. A simple analytical model using squared pulses is used to highlight the physical insight. This model is ‘reinforced’ by numerical simulations on the (4s–4p 2 P 1/2,1/3) transitions in potassium atoms excited with Gaussian pulses. 相似文献
30.
Increasing CaCl2 and lowering pH caused a significant increase in [Ca2+] in reconstituted nonfat dry milk (RNDM), while the addition of soy protein caused a significant reduction in [Ca2+]. Lowering pH greatly increased rennet-induced coagulum firmness in RNDM and slightly increased it in RNDM-soy protein mixtures. Added CaCl2 increased coagulum textural parameters and syneresis in both systems. The extent to which these properties were increased was higher in RNDM than in the coagulum containing soy protein depending on the time after rennet addition and the amount of CaCl2 added. The first increment of CaCl2 added had the highest effect in improving textural properties and increasing syneresis. 相似文献