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21.
Mohamed T. El-Saadony Ahmed M. Saad Hend A. Elakkad Amira M. El-Tahan Omniah A. Alshahrani Mashaeal S. Alshilawi Hanan El-Sayed Shimaa A. Amin Alshaymaa I. Ahmed 《Saudi Journal of Biological Sciences》2022,29(1):346
This work aims to enhance the flavor of functional cucumber juice using herbal extracts of peppermint, basil, lavender, and lemongrass ethanolic extracts and extend its lifetime by controlling the chemical and microbial fluctuations. Cucumber juices were processed as; non-supplemented (J-Con), J-PME, J-BE, J-LE, and J-LEE supplemented with peppermint, basil, lavender, and lemongrass ethanolic extracts, respectively. Peppermint extract was significantly scavenged 88% of DPPH radicals and inhibited the growth of tested gram-positive, gram-negative bacteria and fungi followed by the lemongrass extract. The antioxidant activity of cucumber juices increased due to polyphenols and aroma compounds in the added extracts. However, the antioxidant content was decreased after two months of storage at 4 °C, due to the decrease in polyphenols. The flavor compounds were determined using GC mass, wherein hydrocarbons, acids, alcohols, and carbonyl compounds were the main aroma contents in cucumber juices, and their contents decreased with storage time. Peppermint and lemongrass extracts were significantly (p ≤ 0.05) increased the whiteness of J-PME, and J-LEE, respectively. The highest score of flavor and taste was observed in J-PME that scored 8.3 based on panelists'' reports followed by J-LEE. The PME was significantly maintained 91% of the odor and color of J-PME as compared to other juices. 相似文献
22.
Sarah O. Makled Amira M. Hamdan Abdel-Fattah M. El-Sayed 《Probiotics and antimicrobial proteins》2020,12(2):365-374
A 50-day feeding trial was conducted to evaluate the effects of dietary supplementation of a novel marine psychrotrophic bacterium, Psychrobacter maritimus 相似文献
23.
Walaa I. El-Sofany Othman Dalia Ahmed A. Mahran Asma M. May El-Manawaty A. El-Sayed Wael A. 《Russian Journal of Bioorganic Chemistry》2020,46(3):393-402
Russian Journal of Bioorganic Chemistry - New thienopyrimidine derivatives substituted with amino and hydrazinyl side chains were synthesized starting with 2-hydrazinyl substituted thienopyrimidine... 相似文献
24.
Bringaud F Biteau N Zuiderwijk E Berriman M El-Sayed NM Ghedin E Melville SE Hall N Baltz T 《Molecular biology and evolution》2004,21(3):520-528
The ingi (long and autonomous) and RIME (short and nonautonomous) non--long-terminal repeat retrotransposons are the most abundant mobile elements characterized to date in the genome of the African trypanosome Trypanosoma brucei. These retrotransposons were thought to be randomly distributed, but a detailed and comprehensive analysis of their genomic distribution had not been performed until now. To address this question, we analyzed the ingi/RIME sequences and flanking sequences from the ongoing T. brucei genome sequencing project (TREU927/4 strain). Among the 81 ingi/RIME elements analyzed, 60% are complete, and 7% of the ingi elements (approximately 15 copies per haploid genome) appear to encode for their own transposition. The size of the direct repeat flanking the ingi/RIME retrotransposons is conserved (i.e., 12-bp), and a strong 11-bp consensus pattern precedes the 5'-direct repeat. The presence of a consensus pattern upstream of the retroelements was confirmed by the analysis of the base occurrence in 294 GSS containing 5'-adjacent ingi/RIME sequences. The conserved sequence is present upstream of ingis and RIMEs, suggesting that ingi-encoded enzymatic activities are used for retrotransposition of RIMEs, which are short nonautonomous retroelements. In conclusion, the ingi and RIME retroelements are not randomly distributed in the genome of T. brucei and are preceded by a conserved sequence, which may be the recognition site of the ingi-encoded endonuclease. 相似文献
25.
Feeding stemmadenine to Catharanthus roseus cell suspension culture resulted in the accumulation of catharanthine, tabersonine and condylocarpine. Condylocarpine is not an intermediate in the pathway to catharanthine or tabersonine when it is fed to the cultures. The results support the hypothesis that stemmadenine is an intermediate in the pathway to catharanthine and tabersonine. 相似文献
26.
Ashraf S. El-Sayed 《Applied microbiology and biotechnology》2010,86(2):445-467
l-Methioninase is ubiquitous in all organisms except in mammals. It mainly catalyzes the, α, γ-elimination of l-methionine to α-ketobutyrate, methanethiol, and ammonia. Unlike normal cells, methionine dependency was reported as a biochemical
phenomenon among various types of cancer cells. Thus, l-methioninase is the universal protocol for triggering the majority of tumor cells. This review is an attempt to briefly describe
the occurrence of the biochemical and molecular properties of l-methioninase by a comparative manner to the eukaryotic and prokaryotic source for the maximum exploitation in the therapeutic
field. The combination of l-methioninase treatment, gene therapy, and chemotherapeutic drugs clearly explores the various therapeutic aspects of this
enzyme. Finally, the perspectives for increasing the therapeutic efficacy of this enzyme were described. 相似文献
27.
A flavonoid trioside and its coumaryl ester together with seven known flavonoids and five phenolic acids were isolated from the leaves of Reseda muricata. Their structures were elucidated by spectroscopic methods including UV, FAB MS, 1H, 13C and 2D-NMR, DEPT, HMBC and HMQC experiments. The two compounds were identified as kaempferol 3-O-beta-D-glucopyranosyl-(1' --> 2')-O-alpha-L-rhamnopyranoside 7-O-beta-D-glucopyranoside and kaempferol 3-O-beta-D-glucopyranosyl-(1' --> 2')-O-alpha-L rhamnopyranoside 7-O-beta-D-(6'-O-E-coumarylglucopyranoside), respectively. 相似文献
28.
Growth, metabolic profiling and enzymes activities of Catharanthus roseus seedlings treated with plant growth regulators 总被引:1,自引:0,他引:1
The effect of different growth regulators on growth and the production of terpenoid indole alkaloids as well as some enzymes involved in the biosynthesis were studied in Catharanthus roseus seedlings. The seedlings were grown on MS solid medium containing different concentrations of each growth regulator for a period of one month. Extracted alkaloids were analyzed by HPLC for determination of terpenoid indole alkaloid quantities. Continuous availability of growth regulators induced different alkaloids with variable effects among the regulators. Gibberellic acid at concentration of either 5.8 M or 11.6 M resulted in elongation of shoots with lowering the number of leaves. Abscisic acid has a retardant effect on growth. Ethylene did not effect the growth pattern at concentration of 100 M but seedlings were not tolerant to higher concentrations. Methyljasmonate reduced the growth of the root system. Methyljasmonate was a general inducer for all alkaloids and increased the activity of strictosidine glucosidase. Ethylene applications promoted the pathways towards ajmalicine, serpentine, tabersonine and vindoline. Similar effect as for ethylene was observed for abscisic acid. Salicylic acid treatment increased the production of serpentine, tabersonine and higher concentration of salicylic acid induced vindoline accumulation. Peroxidase activity was also induced by salicylic acid. Gibberellic acid has little effect on alkaloid levels. 相似文献
29.
Bekhit AA El-Sayed OA Aboul-Enein HY Siddiqui YM Al-Ahdal MN 《Journal of enzyme inhibition and medicinal chemistry》2004,19(1):33-38
Synthesis of a novel series of structurally related pyrazoloquinoline nucleosides is described. All the newly synthesized compounds were examined for their in vitro antiviral activity against herpes simplex type-1 as shown by two different bioassays, namely; crystal violet staining or the MTS tetrazolium dye measurement. The acute toxicity (LD50) values of the biologically active compounds were determined. 相似文献
30.
Proton transfer reactions in native and deionized bacteriorhodopsin upon delipidation and monomerization 下载免费PDF全文
We have investigated the role of the native lipids on bacteriorhodopsin (bR) proton transfer and their connection with the cation-binding role. We observe that both the efficiency of M formation and the kinetics of M rise and decay depend on the lipids and lattice but, as the lipids are removed, the cation binding is a much less important factor for the proton pumping function. Upon 75% delipidation using 3-[(cholamidopropyl)dimethylammonio]-propanesulfonate (CHAPS), the M formation and decay kinetics are much slower than the native, and the efficiency of M formation is approximately 30%-40% that of the native. Upon monomerization of bR by Trition X-100, the efficiency of M recovers close to that of the native (depending on pH), M formation is approximately 10 times faster, and M decay kinetics are comparable to native at pH 7. The same results on the M intermediate are observed if deionized blue bR (deI bbR) is treated with these detergents (with or without pH buffers present), even though deionized blue bR containing all the lipids has no photocycle. This suggests that the cation(s) has a role in native bR that is different than in delipidated or monomerized bR, even so far as to suggest that the cation(s) becomes unimportant to the function as the lipids are removed. 相似文献