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11.
Ahmed O.H. El-Nezhawy Majed Alrobaian Ahmed Khames Mohamed F. El-Badawy Sayed F. Abdelwahab 《Bioorganic & medicinal chemistry》2019,27(7):1263-1273
A general strategy towards total synthesis of (-)-codonopsinine, (-)-codonopsine and codonopsinine analogues has been developed from (D)-tartaric acid via the intermediate (3S,4R)-1-methyl-2-oxo-5-(2,2,2-trichloroacetamido)pyrrolidinediacetate (7). α-amidoalkylation studies of 7 with electron rich benzene derivative 8a-g as C-nucleophiles afforded (aryl derivatives) 9a-g. The target compounds 1, 2 and 13c-g were readily obtained from 10a-g via Grignard addition to the homochiral lactam which was produced by deoxygenation using Lewis-acid followed by deacetylation. The synthesized compounds were loaded onto solid lipid nanoparticle formulations (SLNs) prepared by hot emulsification-ultrasonication technique using Compritol as solid lipid and Pluronic f68 as surfactant. SLNs were fully evaluated and the permeation of synthesized compound from SLNs was assayed against non-formulated compounds through dialysis membranes using Franz cell. The data indicated good physical characteristics of the prepared SLNs, sustaining of release profiles and significant improvement of permeation ability when compared to the non-formulated compounds. The antibacterial and antifungal activities of 1, 2 and 13c-g were determined by disc diffusion and microbroth dilution method to determine the minimum inhibitory concentrations (MIC) against seven microorganisms (Staphyloccus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Acinetobacter baumannii and Candida albicans). The most active compounds against the Gram positive S. aureus were 1, 13C, 13d, and 13g. Also, 13c, 13d, and 13e had antibacterial activity but not 13f against some Gram negative organisms (E. coli, and P. mirabilis). MIC concentrations against P. aeruginosa, and K. pneumoniae were?≥512?μg/ml, while that against A. baumannii was?≥128?μg/ml except for nanoformulae of 13e and 13f that were 16 and 64?μg/ml, respectively. No antifungal activity against Candida albicans was recorded for all compounds and their nanoformulae (MIC?>?1024?μg/ml). SLNs were found to decrease the MIC values for some of the compounds with no effect on the antifungal activity. In conclusion, we demonstrated a novel, straight-forward and economical procedure for the total synthesis of (-)-codonopsinine 1, (-)-codonopsine 2 and codonopsinine analogues 13c-g from simple and commercially available starting materials; d-tartaric acid; with antimicrobial activities against Gram positive and Gram-negative organisms that were improved by SLNs formulations. 相似文献
12.
【背景】杨树溃疡病是一种主要由葡萄座腔菌引起的杨树枝干病害,危害严重。前期从杨树中分离到一株内生拮抗细菌N6-34,研究表明该菌株拮抗效果好,对多种植物病原菌均有较强的拮抗作用。【目的】对拮抗细菌N6-34产生的抗菌活性物质进行分离纯化,并鉴定了活性物质组分的结构。【方法】通过硫酸铵盐析、甲醇抽提、分子筛、高效液相色谱等方法分离纯化N6-34菌株的抗菌活性物质,并对其进行结构鉴定。【结果】N6-34菌株发酵液经多步分离纯化,共获得14个组分,其中有13个组分具有抗菌活性,经一级质谱分析,获得了13种抗菌活性组分的分子量;经二级质谱分析,将13种抗菌活性物质鉴定为Fengycin A或Fengycin B的同系物或同分异构体。【结论】从N6-34菌株发酵液中分离获得了13种抗菌成分,为杨树溃疡病的生物防治提供了理论依据。 相似文献
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Heyam Mohamed Ali Sidahmed Najihah Mohd Hashim Mahmood Ameen Abdulla Hapipah Mohd Ali Syam Mohan Siddig Ibrahim Abdelwahab Manal Mohamed Elhassan Taha Loke Mun Fai Jamuna Vadivelu 《PloS one》2015,10(3)
Background
Zingiber zerumbet Smith is a perennial herb, broadly distributed in many tropical areas. In Malaysia, it’s locally known among the Malay people as “lempoyang” and its rhizomes, particularly, is widely used in traditional medicine for the treatment of peptic ulcer disease beyond other gastric disorders.Aim of the study
The aim of the current study is to evaluate the gastroprotective effect of zerumbone, the main bioactive compound of Zingiber zerumbet rhizome, against ethanol-induced gastric ulcer model in rats.Materials and Methods
Rats were pre-treated with zerumbone and subsequently exposed to acute gastric ulcer induced by absolute ethanol administration. Following treatment, gastric juice acidity, ulcer index, mucus content, histological analysis (HE and PAS), immunohistochemical localization for HSP-70, prostaglandin E2 synthesis (PGE2), non-protein sulfhydryl gastric content (NP-SH), reduced glutathione level (GSH), and malondialdehyde level (MDA) were evaluated in ethanol-induced ulcer in vivo. Ferric reducing antioxidant power assay (FRAP) and anti-H. pylori activity were investigated in vitro.Results
The results showed that the intragastric administration of zerumbone protected the gastric mucosa from the aggressive effect of ethanol-induced gastric ulcer, coincided with reduced submucosal edema and leukocyte infiltration. This observed gastroprotective effect of zerumbone was accompanied with a significant (p <0.05) effect of the compound to restore the lowered NP-SH and GSH levels, and to reduce the elevated MDA level into the gastric homogenate. Moreover, the compound induced HSP-70 up-regulation into the gastric tissue. Furthermore, zerumbone significantly (p <0.05) enhanced mucus production, showed intense PAS stain and maintained PG content near to the normal level. The compound exhibited antisecretory activity and an interesting minimum inhibitory concentration (MIC) against H. pylori strain.Conclusion
The results of the present study revealed that zerumbone promotes ulcer protection, which might be attributed to the maintenance of mucus integrity, antioxidant activity, and HSP-70 induction. Zerumbone also exhibited antibacterial action against H. pylori. 相似文献16.
MORAIS PAULO AMORIM ANTÓNIO VIEIRA DA SILVA CLÁUDIA RIBEIRO TERESA COSTA SANTOS JORGE AFONSO COSTA HELOÍSA 《Journal of genetics》2015,94(3):509-512
Journal of Genetics - 相似文献
17.
JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献18.
19.
Sallam SM Abdelgaleil SA Bueno IC Nasser ME Araujo RC Abdalla AL 《Archives of animal nutrition》2011,65(3):203-214
The objectives of this study were to characterise four essential oils (EO) chemically and to evaluate their effect on ruminal fermentation and methane emission in vitro. The investigated EO were isolated from Achillea santolina, Artemisia judaica, Schinus terebinthifolius and Mentha microphylla, and supplemented at four levels (0, 25, 50 and 75 microl) to 75 ml of buffered rumen fluid plus 0.5 g of substrate. The main components of the EO were piperitone (49.1%) and camphor (34.5%) in A. judaica, 16-dimethyl 15-cyclooactdaiene (60.5%) in A. santolina, piperitone oxide (46.7%) and cis-piperitone oxide (28%) in M. microphylla, and gamma-muurolene (45.3%) and alpha-thujene (16.0%) in S. terebinthifolius. The EO from A. santolina (at 25 and 50 j1), and all levels of A. judaica increased the gas production significantly, but S. terebinthifolius (at 50 and 75 microl), A. santolina (at 75 microl) and all levels of M. microphylla decreased the gas production significantly in comparison with the control. The highest levels of A. santolina and A. judaica, and all doses from M. microphylla EO inhibited the methane production along with a significant reduction in true degradation of dry matter and organic matter, protozoa count and NH3-N concentration. It is concluded that the evaluated EO have the potential to affect ruminal fermentation efficiency and the EO from M. microphylla could be a promising methane mitigating agent. 相似文献
20.
Severino A Lucena Leile S Lima Luís SA Cordeiro Jr Celso Sant’Anna Reginaldo Constantino Patricia Azambuja Wanderley de Souza Eloi S Garcia Fernando A Genta 《Biotechnology for biofuels》2011,4(1):1-9