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31.
Addition of methyl oleate to a Streptomyces hygroscopicus NRRL B-1865 culture modified the metabolic properties of this strain. This addition decreased the pH of the medium, increased the valine uptake of the cells and reduced their consumption of glucose until the beginning of antibiotic biosynthesis, which was delayed. At the same time, an increase in growth (× 1.8) and a marked improvement in antibiotic production (× 20) could be observed. The use of labelled methyl oleate showed that methyl oleate was not a precursor of antibiotics produced by S. hygroscopicus NRRL B-1865. It is suggested that methyl oleate addition may cause some alteration in membrane permeability, inducing an increase in H+ extrusion and stimulating the accumulation of branched amino acids, known to be direct precursors of polyether antibiotics. Correspondence to: L. David  相似文献   
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33.
Sickle cell anaemia (SCA) exhibits significant variations in clinical presentation in different populations for which several genetic factors including SCA-associated -and -thalassaemias, G-6-PD deficiency and elevated Hb F level have been implicated as possible ameliorating factors. Saudi Arabia is unique in that mild and severe forms of the disease occur at a high frequency. We investigated the G/A ratio and Hb F level and correlated these values with the severity of SCA. The results showed that Hb F level varies significantly in both groups of patients with no evident correlation with the mild clinical manifestations. However, G/A ratio correlated significantly with the disease severity where a high ratio was observed in patients with the mild and a low ratio in patients with the severe disease. The results are evaluated and discussed in the light of correlation studies and regression analysis.  相似文献   
34.
The online photoreaction of the rose bengal photosensitized luminol–copper (II) chemiluminescence (CL) system was used for the determination of β-nicotinamide adenine dinucleotide (NADH) and ethanol (EtOH) in pharmaceutical formulations combined with a flow injection technique. NADH can significantly enhance the CL emission of the reaction. For EtOH, alcohol dehydrogenase in soluble form was utilized in the presence of nicotinamide adenine dinucleotide resulting in NADH production. The limit of detection (3σ blank, 𝑛 = 3) of 4.0 × 10−8 and 2.17 × 10−5 M, and linear range 1.3 × 10−7 to 2.5 × 10−5 M (R2 = 0.9998, n = 6) and 0.11–2.17 × 10−3 M (R2 = 0.9996, n = 6) were obtained for NADH and EtOH respectively. The injection rate was 100 h−1 with a relative standard deviation (n = 3) of 1.5–4.8% in the range studied for both analytes. The procedure was satisfactorily applied to pharmaceutical formulations with recoveries in the range 91.6 ± 3.0% to 110 ± 2.0% for NADH and 88 ± 3.0% to 95.4 ± 4.0% for EtOH. The results obtained were very consistent and did not differ considerably from the reported approaches at a 95% confidence limit. The possible mechanism of the CL reaction is also explained briefly.  相似文献   
35.
A simple and reproducible procedure for the recovery of plasmid DNA is described. The method was standardised for the purification of plasmids from Gluconobacter oxydans ATCC9937. The protocol is based on the use of glass microfibre filter paper for entrapment of DNA and its subsequent recovery by an elution buffer. The method precludes the use of phenol and butanol for the removal of proteins and ethidium bromide respectively, therefore, making the procedure inexpensive and gentle.  相似文献   
36.
The extensive use of nanoparticles (NPs) in diverse applications causes their localization to aquatic habitats, affecting the metabolic products of primary producers in aquatic ecosystems, such as algae. Synthesized calcium oxide nanoparticles (CaO NPs) are of the scarcely studied NPs. Thus, the current work proposed that the exposure to CaO NPs may instigate metabolic pathway to be higher than that of normally growing algae, and positively stimulate algal biomass. In this respect, this research was undertaken to study the exposure effect of CaO NPs (0, 20, 40, 60, 80, and 100 µg mL−1 ) on the growth, photosynthesis, respiration, oxidative stress, antioxidants, and lipid production of the microalga Coccomyxa chodatii SAG 216-2. The results showed that the algal growth concomitant with chlorophyll content, photosynthesis, and calcium content increased in response to CaO NPs. The contents of biomolecules such as proteins, amino acids, and carbohydrates were also promoted by CaO NPs with variant degrees. Furthermore, lipid production was enhanced by the applied nanoparticles. CaO NPs induced the accumulation of hydrogen peroxide, while lipid peroxidation was reduced, revealing no oxidative behavior of the applied nanoparticles on alga. Also, CaO NPs have a triggering effect on the antioxidant enzymes such as superoxide dismutase, catalase, ascorbate peroxidase, and guaiacol peroxidase. The results recommended the importance of the level of 60 µg mL−1 CaO NPs on lipid production (with increasing percentage of 65% compared to control) and the highest dry matter acquisition of C. chodatii. This study recommended the feasibility of an integrated treatment strategy of CaO NPs in augmenting biomass, metabolic up-regulations, and lipid accumulation in C. chodatii.  相似文献   
37.
Cancer is one of the main challenges of the health system around the world. This disease is increasing in developing countries and imposes heavy costs on patients and governments. On the other hand, despite various drugs, the death rate among cancer patients is still high and the current treatments have many harmful effects. In the traditional medicine of different countries, there are many medicinal plants that can be effective in the treatment of cancer. Ferula plants are traditionally used as spices and food or for medicinal purposes. Ferula assa-foetida is one of the famous plants of this genus, which has been used for the treatment of various diseases since ancient times. Among the main compounds of this plant, we can mention monoterpenes, sulfide compounds and polyphenols, which can show different therapeutic effects. This article has been compiled with the aim of collecting evidence and articles related to the anti-cancer effects of extracts, derived compounds, essential oils and nanoparticles containing Ferula assa-foetida. This review article was prepared by searching the terms Ferula assa-foetida and cancer, and relevant information was collected through searching electronic databases such as ISI Web of Knowledge, PubMed, and Google Scholar. Fortunately, the results of this review showed that relatively comprehensive studies have been conducted in this field and shown that Ferula assa-foetida can be very promising in the treatment of cancer.  相似文献   
38.
Indanone derivatives containing meta/para-substituted aminopropoxy benzyl/benzylidene moieties were designed based on the structures of donepezil and ebselen analogs as the cholinesterase inhibitors. The designed compounds were synthesized and their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were measured. Inhibitory potencies (IC50 values) for the synthesized compounds ranged from 0.12 to 11.92 μM and 0.04 to 24.36 μM against AChE and BChE, respectively. Compound 5 c showed the highest AChE inhibitory potency with IC50 value of 0.12 μM, whereas the highest BChE inhibition was achieved by structure 7 b (IC50=0.04 μM). Structure-activity relationship (SAR) analysis revealed that there is no significant difference between meta and para-substituted derivatives in AChE and BChE inhibition. However, the most potent AChE inhibitor 5 c belongs to meta-substituted compounds, while the most active BChE inhibitor is para-substituted derivative 7 b . The order of enzyme inhibition potency based on the substituted amine group is dimethyl amine>piperidine>morpholine. Compounds containing C=C linkage are more potent AChE inhibitors than the corresponding saturated structures. Molecular docking studies indicated that 5 c interacts with AChE in a very similar way to that observed experimentally for donepezil. The introduced indanone-aminopropoxy benzylidenes could be used in drug-discovery against Alzheimer's disease.  相似文献   
39.
This study aimed to assess the anthelmintic activity of methanol extracts from Merremia vitifolia stems using a combination approach encompassing experimental, in vitro, and in silico evaluations. Despite the well-recognized pharmacological properties of M. vitifolia, its potential as an anthelmintic agent remained unexplored. This plant's anthelmintic potential was assessed on adult earthworms (Pheretima posthuma), revealing a dose-dependent reduction in spontaneous motility leading to paralysis and eventual mortality. The most effective dose of M. vitifolia (200 mg/ml) for anthelmintic effects on Pheretima posthuma was identified. Complementary in silico investigations were also conducted, employing Autodock PyRx 0.8 for docking studies of reported M. vitifolia compounds. Notably, quercetin emerged as a promising candidate with superior binding energies against β-tubulin (−8.3 Kcal/mol). Moreover, this comprehensive research underlines the anthelmintic potential of Merremia vitifolia stem extract and highlights quercetin as a noteworthy compound for further investigation in the quest for novel anthelmintic agents.  相似文献   
40.
Blood serum is arguably the most analyzed biofluid for disease prediction and diagnosis. Herein, we benchmarked five different serum abundant protein depletion (SAPD) kits with regard to the identification of disease-specific biomarkers in human serum using bottom-up proteomics. As expected, the IgG removal efficiency among the SAPD kits is highly variable, ranging from 70% to 93%. A pairwise comparison of database search results showed a 10%–19% variation in protein identification among the kits. Immunocapturing-based SAPD kits against IgG and albumin outperformed the others in the removal of these two abundant proteins. Conversely, non-antibody-based methods (i.e., kits using ion exchange resins) and kits leveraging a multi-antibody approach were proven to be less efficient in depleting IgG/albumin from samples but led to the highest number of identified peptides. Notably, our results indicate that different cancer biomarkers could be enriched up to 10% depending on the utilized SAPD kit compared with the undepleted sample. Additionally, functional analysis of the bottom-up proteomic results revealed that different SAPD kits enrich distinct disease- and pathway-specific protein sets. Overall, our study emphasizes that a careful selection of the appropriate commercial SAPD kit is crucial for the analysis of disease biomarkers in serum by shotgun proteomics.  相似文献   
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