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51.
Pessani NK Atiyeh HK Wilkins MR Bellmer DD Banat IM 《Bioresource technology》2011,102(22):10618-10624
Switchgrass (Panicum virgatum) was subjected to hydrothermolysis pretreatment and then used to study the effect of enzyme loading and temperature in a simultaneous saccharification and fermentation (SSF) with the thermotolerant yeast strain Kluyveromyces marxianus IMB3 at 8% solid loading. Various loadings of Accellerase 1500 between 0.1 and 1.1 mL g(-1) glucan were tested in SSF at 45 °C (activity of enzyme was 82.2 FPU mL(-1)). The optimum enzyme loading was 0.7 mL g(-1) glucan based on the six different enzyme loadings tested. SSFs were performed at 37, 41 and 45 °C with an enzyme loading of 0.7 mL g(-1) glucan. The highest ethanol concentration of 22.5 g L(-1) was obtained after 168 h with SSF at 45 °C, which was equivalent to 86% yield. Four different batch and fed-batch strategies were evaluated using a total solid loading of 12% (dry basis). About 32 g L(-1) ethanol was produced with the four strategies, which was equivalent to 82% yield. 相似文献
52.
温室条件下,用0(Control)、8.65kJm-2d-1(TI)及11.2KJm-2d-1(t2)不同剂量的UV-B辐射处理蚕豆幼苗。Ca2 .ATPase及Mg2 -ATPase的活性在辐射处理期间下降。在处理21d,T1和T2微粒体膜的MDA含量明显高于对照,同时IUFA急剧下降,且呈明显的剂量效应。14及21d时,膜磷脂的含量也明显下降。脂氧合酶(Lox)活性在第7及14天与对照相比都显著升高,而21d后迅速下降。结果表明,增强UV-B对微粒体膜的伤害可能是一方面导致正常酶合成与分解之间的平衡失调,另一方面导致了膜脂过氧化作用。 相似文献
53.
Adnan A. Bekhit Eskedar T. Lodebo Ariaya Hymete Hanan M. Ragab Salma A. Bekhit Kikuko Amagase Afnan Batubara Mohammed A. S. Abourehab Alaa El-Din A. Bekhit Tamer M. Ibrahim 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):2320
Promising inhibitory activities of the parasite multiplication were obtained upon evaluation of in vivo antimalarial activities of new pyrazolylpyrazoline derivatives against Plasmodium berghei infected mice. Further evaluation of 5b and 6a against chloroquine-resistant strain (RKL9) of P. falciparum showed higher potency than chloroquine. In vitro antileishmanial activity testing against Leishmania aethiopica promastigote and amastigote forms indicated that 5b, 6a and 7b possessed promising activity compared to miltefosine and amphotericin B deoxycholate. Moreover, antileishmanial activity reversal of the active compounds via folic and folinic acids showed comparable results to the positive control trimethoprim, indicating an antifolate mechanism via targeting leishmanial DHFR and PTR1. The compounds were non-toxic at 125, 250 and 500 mg/kg. In addition, docking of the most active compound against putative malarial target Pf-DHFR-TS and leishmanial PTR1 rationalised the observed activities. Molecular dynamics simulations confirmed a stable and high potential binding of 7a against leishmanial PTR1. 相似文献
54.
Mohammed S. Taghour Hazem Elkady Wagdy M. Eldehna Nehal M. El-Deeb Ahmed M. Kenawy Eslam B. Elkaeed Aisha A. Alsfouk Mohamed S. Alesawy Ahmed M. Metwaly Ibrahim. H. Eissa 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1903
A thiazolidine-2,4-dione nucleus was molecularly hybridised with the effective antitumor moieties; 2-oxo-1,2-dihydroquinoline and 2-oxoindoline to obtain new hybrids with potential activity against VEGFR-2. The cytotoxic effects of the synthesised derivatives against Caco-2, HepG-2, and MDA-MB-231 cell lines were investigated. Compound 12a was found to be the most potent candidate against the investigated cell lines with IC50 values of 2, 10, and 40 µM, respectively. Furthermore, the synthesised derivatives were tested in vitro for their VEGFR-2 inhibitory activity showing strong inhibition. Moreover, an in vitro viability study against Vero non-cancerous cell line was investigated and the results reflected a high safety profile of all tested compounds. Compound 12a was further investigated for its apoptotic behaviour by assessing the gene expression of four genes (Bcl2, Bcl-xl, TGF, and Survivin). Molecular dynamic simulations authenticated the high affinity, accurate binding, and perfect dynamics of compound 12a against VEGFR-2. 相似文献
55.
56.
Nada H. El-Dershaby Soad A. El-Hawash Shaymaa E. Kassab Hoda G. Dabees Ahmed E. Abdel Moneim Ibrahim A. Abdel Wahab Mohammad M. Abd-Alhaseeb Mostafa M. M. El-Miligy 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1737
A new series of co-drugs was designed based on hybridising the dihydropteroate synthase (DHPS) inhibitor sulphonamide scaffold with the COX-2 inhibitor salicylamide pharmacophore through biodegradable linkage to achieve compounds with synergistic dual inhibition of COX-2/PGE2 axis and DHPS enzyme to enhance antibacterial activity for treatment of septicaemia. Compounds 5 b, 5j, 5n and 5o demonstrated potent in vitro COX-2 inhibitory activity comparable to celecoxib. 5j and 5o exhibited ED50 lower than celecoxib in carrageenan-induced paw edoema test with % PGE2 inhibition higher than celecoxib. Furthermore, 5 b, 5j and 5n showed gastric safety profile like celecoxib. Moreover, in vivo antibacterial screening revealed that, 5j showed activity against S.aureus and E.coli higher than sulfasalazine. While, 5o revealed activity against E.coli higher than sulfasalazine and against S.aureus comparable to sulfasalazine. Compound 5j achieved the target goal as potent inhibitor of COX-2/PGE2 axis and in vivo broad-spectrum antibacterial activity against induced septicaemia in mice. 相似文献
57.
Radhika AiyappaMaudsley Lina Elsalem Ali I. M. Ibrahim Klaus Pors Stewart G. Martin 《Journal of cellular and molecular medicine》2022,26(16):4577
KP167 is a novel hypoxia‐activated prodrug (HAP), targeting cancer cells via DNA intercalating and alkylating properties. The single agent and radiosensitizing efficacy of KP167 and its parental comparator, AQ4N, were evaluated in 2D and 3D cultures of luminal and triple negative breast cancer (TNBC) cell lines and compared against DNA damage repair inhibitors. 2D normoxic treatment with the DNA repair inhibitors, Olaparib or KU‐55933 caused, as expected, substantial radiosensitization (sensitiser enhancement ratio, SER0.01 of 1.60–3.42). KP167 induced greater radiosensitization in TNBC (SER0.01 2.53 in MDAMB‐231, 2.28 in MDAMB‐468, 4.55 in MDAMB‐436) and luminal spheroids (SER0.01 1.46 in MCF‐7 and 1.76 in T47D cells) compared with AQ4N. Significant radiosensitization was also obtained using KP167 and AQ4N in 2D normoxia. Although hypoxia induced radioresistance, radiosensitization by KP167 was still greater under 2D hypoxia, yielding SER0.01 of 1.56–2.37 compared with AQ4N SER0.01 of 1.13–1.94. Such data show KP167 as a promising single agent and potent radiosensitiser of both normoxic and hypoxic breast cancer cells, with greater efficacy in TNBCs. 相似文献
58.
Summary The formation of itaconic, aconitic and other acids from glucose in the presence of some enzyme inhibitors or organic acids by Aspergillus terreus was studied. Moreover, the metabolic activities of the preformed mats when floated on solutions of some organic acids were traced.When the resulting information were collected together a presumed condensation reaction between acetate and succinate could be formulated. The reaction product, presumably 1, 2, 3 propane tricarboxylic acid, would undergo a dehydrogenation reaction to yield aconitic acid and subsequently itaconic acid. It has also been suggested that aconityl CoA may be the metabolic form which suits the reactions leading to the formation of itaconic acid. The presumed aconityl CoA may be formed either through a condensation reaction between acetyl CoA and succinate or acetate with succinyl CoA. 相似文献
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60.
Summary The antibacterial effect of negapillin in combination with other antibiotics and sulfa drugs was studied using Gram+ve and Gram-ve bacteria as test organisms. Subsequently, various proportions of negapillin in combination with the antibiotics and the sulfa drugs were examined to determine the optimum proportions which exert maximum inhibitory effects on the bacterial growth. Mixtures of these antibiotics with negapillin were found more superior not only as antimicrobial agents but also for having comparatively low toxicity. 相似文献