Improvement of production yield of l-cysteine through in vitro metabolic pathway with thermophilic enzymes

Background:: Antifungal cyclic lipopeptides, bioactive metabolites produced by many species of the genus Bacillus, are promising alternatives to synthetic fungicides and antibiotics for the biocontrol of human pathogenic fungi. In a previous study, the co- production of five antifungal lipopeptides homologues (designated as AF1, AF2, AF3, AF4 and AF5) by the producer strain Bacillus subtilis RLID 12.1 using unoptimized medium was reported; though the two homologues AF3 and AF5 differed by 14 Da and in fatty acid chain length were found effective in antifungal action, the production/ yield rate of these two lipopeptides determined by High-Performance Liquid Chromatography was less in the unoptimized media. Methods:: In this study, the production/yield enhancement of the two compounds AF3 and AF5 was specifically targeted. Following the statistical optimization (Plackett-Burman and Box-Behnken designs) of media formulation, temperature and growth conditions, the production of AF3 and AF5 was improved by about 25.8- and 7.4-folds, respectively under static conditions. Results:: To boost the production of these two homologous lipopeptides in the optimized media, heat-inactivated Candida albicans cells were used as a supplement resulting in 34- and 14-fold increase of AF3 and AF5, respectively. Four clinical Candida auris isolates had AF3 and AF5 MICs (100 % inhibition) ranging between 4 and 16 μg/ml indicating the lipopeptide’s clinical potential. To determine the in vitro pharmacodynamic potential of AF3 and AF5, time-kill assays were conducted which showed that AF3 (at 4X and 8X concentrations) at 48h exhibited mean log reductions of 2.31 and 3.14 CFU/ml of C. albicans SC 5314, respectively whereas AF5 at 8X concentration showed a mean log reduction of 2.14 CFU/ml. Conclusion:: With the increasing threat of multidrug-resistant yeasts and fungi, these antifungal lipopeptides produced by optimized method promise to aid in the development of novel antifungal that targets disease-causing fungi with improved efficacy.

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AZD-3043

Anesthesiology ◽

10.1097/aln.0b013e31825685a6 ◽

2012 ◽

Vol 116 (6) ◽

pp. 1267-1277 ◽

Cited By ~ 21

Author(s):

Talmage D. Egan ◽

Shinju Obara ◽

Thomas E. Jenkins ◽

Sarah S. Jaw-Tsai ◽

Shanti Amagasu ◽

...

Keyword(s):

Dynamic Model ◽

Metabolic Pathway ◽

Liver Microsomes ◽

Allosteric Modulator ◽

Positive Allosteric Modulator ◽

Duration Of Action ◽

Chloride Currents ◽

Gaba A ◽

Hypnotic Agent

Background Propofol can be associated with delayed awakening after prolonged infusion. The aim of this study was to characterize the preclinical pharmacology of AZD-3043, a positive allosteric modulator of the γ-aminobutyric acid type A (GABA(A)) receptor containing a metabolically labile ester moiety. The authors postulated that its metabolic pathway would result in a short-acting clinical profile. Methods The effects of AZD-3043, propofol, and propanidid were studied on GABA(A) receptor-mediated chloride currents in embryonic rat cortical neurons. Radioligand binding studies were also performed. The in vitro stability of AZD-3043 in whole blood and liver microsomes was evaluated. The duration of the loss of righting reflex and effects on the electroencephalograph evoked by bolus or infusion intravenous administration were assessed in rats. A mixed-effects kinetic-dynamic model using minipigs permitted exploration of the clinical pharmacology of AZD-3043. Results AZD-3043 potentiated GABA(A) receptor-mediated chloride currents and inhibited [(35)S]tert-butylbicyclophosphorothionate binding to GABA(A) receptors. AZD-3043 was rapidly hydrolyzed in liver microsomes from humans and animals. AZD-3043 produced hypnosis and electroencephalograph depression in rats. Compared with propofol, AZD-3043 was shorter acting in rats and pigs. Computer simulation using the porcine kinetic-dynamic model demonstrated that AZD-3043 has very short 50 and 80% decrement times independent of infusion duration. Conclusions AZD-3043 is a positive allosteric modulator of the GABA(A) receptor in vitro and a sedative-hypnotic agent in vivo. The esterase dependent metabolic pathway results in rapid clearance and short duration of action even for long infusions. AZD-3043 may have clinical potential as a sedative-hypnotic agent with rapid and predictable recovery.

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Formulation and Evaluation of Luliconazole Microsponges Loaded Gel for Topical Delivery

Research Journal of Pharmacy and Technology ◽

10.52711/0974-360x.2021.01004 ◽

2021 ◽

pp. 5775-5780

Author(s):

Farhana Sultan ◽

Himansu Chopra ◽

Gyanendra Kumar Sharma

Keyword(s):

Controlled Release ◽

Drug Release ◽

Ethyl Cellulose ◽

Entrapment Efficiency ◽

Topical Delivery ◽

Production Yield ◽

In Vitro Drug Release ◽

Eudragit Rs ◽

Diffusion Studies

Microsponge containing Luliconazole (LCZ) with different proportion of drug:polymer (Ethyl cellulose and Eudragit RS 100) were obtained efficiently using Quasi-emulsion solvent diffusion method. Luliconazole is an anti-fungal drug used for the topical delivery. The purpose of the microsponge formulation is to control the release of LCZ drug to the skin through Microsponge Delivery System (MDS) known to be the novel technique which overcome the maximum concentration of active ingredient, frequency doses, and skin irritation. The prepared microsponges were examined using drug content, % production yield, % entrapment efficiency and in-vitro drug release. The formulation were subjected to in-vitro drug release studies for 6 hr in which it was concluded that Ethyl cellulose microsponges formulated by drug:polymer (1:1) and Eudragit RS 100 microsponges formulated by drug:polymer (1:3) showed maximum controlled release i.e., Increase in drug:polymer ratio (1:1 to 1:9) increased the production yield and entrapment efficiency of microsponges using Ethyl cellulose with no significant effect for Eudragit RS 100.Therefore, both formulation F1 and F2 was dispersed in carbopol gel preparation for controlled delivery of LCZ to the skin. Various physical parameters like pH, spreadability, viscosity and in-vitro drug diffusion studies were evaluated for the prepared gel formulations. Microsponge gel formulation i.e., FG1 showed better results for controlled release of 89.40% as compared to FG2 i.e., 92.18% over the period of 12 hrs which is performed in Franz Diffusion Cell. On basis of in-vitro diffusion studies for LCZ gel formulation, microsponges using Ethyl cellulose (FG1) was found to be best for its controlled release of LCZ for 12 hrs and followed zero order kinetics. Hence, formulated LCZ loaded gel have potential to treat fungal infections i.e., tinea pedis, tinea cruris and tinea corporis.

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Thermophilic enzymes for synthetic biology in vivo and in vitro cascades

New Biotechnology ◽

10.1016/j.nbt.2018.05.1205 ◽

2018 ◽

Vol 44 ◽

pp. S63

Author(s):

J. Littlechild

Keyword(s):

Synthetic Biology ◽

Thermophilic Enzymes

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A novel nucleoside rescue metabolic pathway may be responsible for therapeutic effect of orally administered cordycepin

Scientific Reports ◽

10.1038/s41598-019-52254-x ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Jong Bong Lee ◽

Masar Radhi ◽

Elena Cipolla ◽

Raj D. Gandhi ◽

Sarir Sarmad ◽

...

Keyword(s):

Oral Administration ◽

Metabolic Pathway ◽

Oral Absorption ◽

Therapeutic Effects ◽

The Novel ◽

Drug Candidates ◽

Biopharmaceutical Properties

Abstract Although adenosine and its analogues have been assessed in the past as potential drug candidates due to the important role of adenosine in physiology, only little is known about their absorption following oral administration. In this work, we have studied the oral absorption and disposition pathways of cordycepin, an adenosine analogue. In vitro biopharmaceutical properties and in vivo oral absorption and disposition of cordycepin were assessed in rats. Despite the fact that numerous studies showed efficacy following oral dosing of cordycepin, we found that intact cordycepin was not absorbed following oral administration to rats. However, 3′-deoxyinosine, a metabolite of cordycepin previously considered to be inactive, was absorbed into the systemic blood circulation. Further investigation was performed to study the conversion of 3′-deoxyinosine to cordycepin 5′-triphosphate in vitro using macrophage-like RAW264.7 cells. It demonstrated that cordycepin 5′-triphosphate, the active metabolite of cordycepin, can be formed not only from cordycepin, but also from 3′-deoxyinosine. The novel nucleoside rescue metabolic pathway proposed in this study could be responsible for therapeutic effects of adenosine and other analogues of adenosine following oral administration. These findings may have importance in understanding the physiology and pathophysiology associated with adenosine, as well as drug discovery and development utilising adenosine analogues.

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Identification and characterization of cytochrome P450 1232A24 and 1232F1 from Arthrobacter sp. and their role in the metabolic pathway of papaverine

The Journal of Biochemistry ◽

10.1093/jb/mvz010 ◽

2019 ◽

Vol 166 (1) ◽

pp. 51-66 ◽

Cited By ~ 2

Author(s):

Jan M Klenk ◽

Max-Philipp Fischer ◽

Paulina Dubiel ◽

Mahima Sharma ◽

Benjamin Rowlinson ◽

...

Keyword(s):

Cytochrome P450 ◽

Metabolic Pathway ◽

Biochemical Characterization ◽

Gene Clusters ◽

Cytochrome P450 Monooxygenases ◽

Dihydroxyphenylacetic Acid ◽

Meta Position ◽

Redox Partners

AbstractCytochrome P450 monooxygenases (P450s) play crucial roles in the cell metabolism and provide an unsurpassed diversity of catalysed reactions. Here, we report the identification and biochemical characterization of two P450s from Arthrobacter sp., a Gram-positive organism known to degrade the opium alkaloid papaverine. Combining phylogenetic and genomic analysis suggested physiological roles for P450s in metabolism and revealed potential gene clusters with redox partners facilitating the reconstitution of the P450 activities in vitro. CYP1232F1 catalyses the para demethylation of 3,4-dimethoxyphenylacetic acid to homovanillic acid while CYP1232A24 continues demethylation to 3,4-dihydroxyphenylacetic acid. Interestingly, the latter enzyme is also able to perform both demethylation steps with preference for the meta position. The crystal structure of CYP1232A24, which shares only 29% identity to previous published structures of P450s helped to rationalize the preferred demethylation specificity for the meta position and also the broader substrate specificity profile. In addition to the detailed characterization of the two P450s using their physiological redox partners, we report the construction of a highly active whole-cell Escherichia coli biocatalyst expressing CYP1232A24, which formed up to 1.77 g l−1 3,4-dihydroxyphenylacetic acid. Our results revealed the P450s’ role in the metabolic pathway of papaverine enabling further investigation and application of these biocatalysts.

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P156 - In vitro metabolism of bardoxolone, an activator of NRF2 via reversible covalent modification of KEAP1: Formation of bardoxolone epoxide and novel metabolic pathway for oxidative denitrilation via reductive addition of glutathione

Drug Metabolism and Pharmacokinetics ◽

10.1016/j.dmpk.2020.04.157 ◽

2020 ◽

Vol 35 (1) ◽

pp. S70

Author(s):

Amin Kamel

Keyword(s):

Metabolic Pathway ◽

Covalent Modification ◽

In Vitro Metabolism ◽

Reversible Covalent

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Development and Characterization of Glimepiride Novel Solid Nanodispersion for Improving Its Oral Bioavailability

Scientia Pharmaceutica ◽

10.3390/scipharm88040052 ◽

2020 ◽

Vol 88 (4) ◽

pp. 52

Author(s):

Mona Qushawy ◽

Ali Nasr ◽

Shady Swidan ◽

Yasmin Mortagi

Keyword(s):

Solid Dispersion ◽

Drug Carrier ◽

In Vitro Release ◽

Water Soluble ◽

Production Yield ◽

Scanning Calorimetry ◽

Differential Scanning Calorimetry Study ◽

Drug Content ◽

Vitro Release

Glimepiride is an antidiabetic drug which is one of the third generation sulfonylureas. It belongs to class II, according to the BCS (Biopharmaceutical Classification System), which is characterized by low solubility and high permeability. The aim of this work was to formulate glimepiride as solid dispersion using water-soluble carriers to enhance its aqueous solubility and thus enhance its bioavailability. Nine formulations of glimepiride solid dispersion were prepared by a solvent evaporation technique using three different carriers (mannitol, polyethylene glycol 6000, and β-cyclodextrin) with three different drug carrier ratio (1:1, 1:3, and 1:6). Formulation variables were optimized using 32 full factorial design. The prepared formulations were evaluated for production yield, drug content, micromeritic properties, thermal analysis, in-vitro release, and in-vivo hypoglycemic effect. All prepared formulations showed high production yield ranged from 98.4 ± 2.8 to 99.8 ± 2.2% and high drug content in the range of 97.2 ± 3.2 to 99.6 ± 2.1%. The micromeritic properties revealed that all prepared glimepiride formulations showed good flowability. The differential scanning calorimetry study revealed the presence of the drug in the more soluble amorphous form. In accordance with the results of in vitro release study, it was found that the solubility of glimepiride was increased by increasing the drug carrier ratio, compared with the pure form of the drug. It was found that F9 showed a high and rapid reduction in blood glucose levels in diabetic rats, which indicated the success of a solid dispersion technique in improving the solubility and hence the bioavailability of glimepiride.

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