scholarly journals Penicillins’ Solubility in Supercritical Carbon Dioxide: Modeling by Cubic Equations of States Revisited

Antibiotics ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1448
Author(s):  
Loubna Nasri
Keyword(s):  
Penicillin G ◽  
Green Solvents ◽  
Modeling Framework ◽  
Benzyl Penicillin ◽  
Phenoxymethyl Penicillin ◽  
Equation Of States ◽  
Compressed Gas ◽  
Pharmaceutical Industries ◽  
Thermodynamics Modeling ◽  
Experimental Values

Development of processes using green solvents as supercritical fluids (SCFs) depends on the accuracy of modeling and predicting phase equilibrium which is of considerable importance to exploit the use of SCF process at the level of pharmaceutical industries. Solid-Fluid equilibrium modeling is associated to many drawbacks when compressed gas-based models as cubic equations of states (cEoSs) are used. The unavailability of experimental values of solute’s sublimation pressure presents one of the major obstacles to the solubility modeling with this type of models, and thus, its estimation is essential and inevitable. This work is an attempt to address a question regarding “accurate estimated value” of sublimation pressure of two antibiotics Penicillin G (benzyl penicillin) and Penicillin V (phenoxymethyl penicillin). Toward that, first, cEoSs are provided as the thermodynamics modeling framework and fundamental approach. Second, a discussion and a review of some literature results are given. Third, results are invoked to present a criticism analysis that comes from the use of modified form of Peng-Robinson (PR) equation of states. Finally, considerable improvement of modeling results by using a new sublimation pressure is shown.

In Vivo Sensitivity Test in Otitis Media: Efficacy of Antibiotics

PEDIATRICS ◽  
1985 ◽  
Vol 75 (1) ◽  
pp. 8-13 ◽  
Author(s):  
Virgil M. Howie ◽  
Ruth Dillard ◽  
Barbara Lawrence
Keyword(s):  
Otitis Media ◽  
Middle Ear ◽  
Penicillin G ◽  
Treatment Results ◽  
Double Blind ◽  
Phenoxymethyl Penicillin ◽  
Procaine Penicillin ◽  
The Poor

During a 10-year period, antibiotics were assigned in random, double-blind fashion in six combinations to treat 948 episodes of otitis media in children. Exudate from the middle ear of all patients was cultured before treatment. Three follow-up visits were conducted; the first follow-up visit was three to five days after the start of therapy, and the second and third visits were 14 and 31 days after onset of treatment. Exudates were recultured for 75% of the patients on the first follow-up visit. Comparison of treatment results showed that triple sulfonamide combined with either phenoxymethyl penicillin, or benzathine and procaine penicillin G given intramuscularly (IM) was as effective as was ampicillin or amoxicillin. Phenoxymethyl penicillin and cyclacillin alone were usually effective against pneumococci but relatively ineffective against Haemophilus influenzae. Cefaclor and trimethoprim-sulfamethoxazole produced unsatisfactory results in about half the cases caused by pneumococci or H influenzae. Although production of β-lactamase by some otitis-causing Haemophilus and Staphylococcus species may explain the ineffectiveness of some treatments, the percentage of organisms positive for β-lactamase was too small to be responsible for the poor results with certain drugs.

scholarly journals Eco-Friendly Extraction and Characterisation of Nutraceuticals from Olive Leaves

Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3481 ◽  
Author(s):  
Cinzia Benincasa ◽  
Ilaria Santoro ◽  
Monica Nardi ◽  
Alfredo Cassano ◽  
Giovanni Sindona
Keyword(s):  
Olive Tree ◽  
Food Supplement ◽  
Industrial Applications ◽  
Added Value ◽  
Green Solvents ◽  
Olive Leaves ◽  
Liquid Chromatography Tandem Mass ◽  
Pharmaceutical Industries ◽  
High Concentrations ◽  
Extraction Power

Olive tree (Olea europaea L.) leaf, a waste by-product of the olive oil industry, is an inexpensive and abundant source of biophenols of great interest for various industrial applications in the food supplement, cosmetic, and pharmaceutical industries. In this work, the aqueous extraction of high-added value compounds from olive leaves by using microfiltered (MF), ultrapure (U), and osmosis-treated (O) water was investigated. The extraction of target compounds, including oleuropein (Olp), hydroxytyrosol (HyTyr), tyrosol (Tyr), verbascoside (Ver), lutein (Lut), and rutin (Rut), was significantly affected by the characteristics of the water used. Indeed, according to the results of liquid chromatography tandem mass spectrometry, the extracting power of microfiltered water towards rutin resulted very poor, while a moderate extraction was observed for oleuropein, verbascoside, and lutein. On the other hand, high concentrations of hydroxytyrosol were detected in the aqueous extracts produced with microfiltered water. The extraction power of ultrapure and osmosis-treated water proved to be very similar for the bio-active compounds oleuropein, verbascoside, lutein, and rutin. The results clearly provide evidence of the possibility of devising new eco-friendly strategies based on the use of green solvents which can be applied to recover bioactive compounds from olive leaves.

scholarly journals MEASURING THE PRE-HEATING TEMPERATURE OF THE PLATES SURFACE WITH IMPACT GAS IN THE WELDING GAP DURING EXPLOSION WELDING

2021 ◽  
pp. 5-11
Author(s):  
S. V. Khaustov ◽  
V. V. Pai ◽  
Ya. L. Lukyanov ◽  
S. V. Kuz’min ◽  
V. I. Lysak ◽  
...  
Keyword(s):  
Heat Flux ◽  
Satisfactory Agreement ◽  
Heating Temperature ◽  
Theoretical Calculations ◽  
Explosion Welding ◽  
Compressed Gas ◽  
Experimental Values ◽  
First Time

A technique for measuring the heat flux from the shock-compressed gas in front of the point of contact to the surface of the colliding plates has been developed. The experimental values of the heat flux are obtained, which are in satisfactory agreement with theoretical calculations. For the first time experimentally proved a significant effect of preheating of plates before collision for various materials. The effect consists in heating the surface of the plates, depending on their dimensions and properties, up to 1000 ° C and above.

A Comparative Experimental Study of the Circulation of Amoxycillin and Penicillin G in the Cerebro-Spinal Fluid of Dogs as a Function of the Type of Intravenous Administration

1974 ◽  
Vol 2 (3) ◽  
pp. 189-196 ◽  
Author(s):  
J C Auvergnat
Keyword(s):  
Cerebrospinal Fluid ◽  
Intravenous Infusion ◽  
Glucose Solution ◽  
Penicillin G ◽  
Intravenous Route ◽  
Benzyl Penicillin ◽  
Biological Technique ◽  
Slow Infusion ◽  
Comparison Of The Results ◽  
Slow Intravenous Infusion

The circulation of amoxycillin in the cerebrospinal fluid when the antibiotic is administered by the intravenous route has been investigated in dogs—animals generally used as the model for experimental meningitis—following two procedures: by rapid intravenous injection ( 1 g in 10 ml within one minute) or by slow intravenous infusion for one hour ( 1 g in 120 ml of isotonic glucose solution). Results were compared with those obtained with benzyl penicillin given by the same procedure and at an equivalent dose ( 1 g amoxycillin: 2 000 000 IU benzyl penicillin). Assays were carried out, in cerebrospinal fluid and blood, using the standard micro-biological technique. Comparison of the results obtained after the two procedures shows that after slow intravenous infusion, concentrations of the two antibiotics in cerebrospinal fluid and blood are higher after administration by slow infusion. Furthermore the concentrations of amoxycillin obtained in cerebrospinal fluid by slow infusion are significantly higher than those of penicillin; but in blood the reverse occurs. This study would suggest that amoxycillin possesses a greater ability to permeate into meningeal regions.

scholarly journals Polyhydroxyalkanoates, bacterially synthesized polymers, as a source of chemical compounds for the synthesis of advanced materials and bioactive molecules

2021 ◽  
Author(s):  
Maciej W. Guzik
Keyword(s):  
Chemical Compounds ◽  
Bioactive Molecules ◽  
Advanced Materials ◽  
Green Solvents ◽  
Bioactive Substances ◽  
Everyday Objects ◽  
Physicochemical Features ◽  
Pharmaceutical Industries ◽  
Medical Materials ◽  
Academy Of Sciences

AbstractResearch into polyhydroxyalkanoates (PHAs) is growing exponentially. These bacterially derived polyesters offer a spectrum of possible applications, such as in manufacturing of daily-use objects, production of medical devices and implantable objects, or as synthons in chemical and pharmaceutical industries. Thanks to their broad physicochemical features, PHAs can be seen as polymers of the future, which can replace traditional petrochemical equivalents. As they are synthesized by bacteria through fermentation processes, these polyesters can be obtained from virtually any carbon source in a sustainable manner. Characterized by biodegradability and biocompatibility, they are used in many industries, ranging from production of everyday objects to medical applications. Furthermore, as they are built from bioactive monomers, namely (R)-3-hydroxyacids, they provide a platform for the synthesis of advanced chemical compounds. In this mini review, the reader will be acquainted with recent studies conducted at the Jerzy Haber Institute of Catalysis and Surface Chemistry of the Polish Academy of Sciences in collaboration with other groups that have contributed to the development of PHA-based medical materials, bioactive molecules and novel green solvents derived from PHA monomers.Key points• Polyhydroxyalkanoates are emerging polymers for biomedical applications• Polyhydroxyalkanoates can be modified easily to provide novel materials• (R)-3-Hydroxyacids are good synthons for bioactive substances and green solvents

Benzyl-penicillin (Penicillin G) transformation in aqueous solution at low temperature under controlled laboratory conditions

Chemosphere ◽  
2010 ◽  
Vol 81 (11) ◽  
pp. 1477-1485 ◽  
Author(s):  
Marlies Bergheim ◽  
Tone Helland ◽  
Roland Kallenborn ◽  
Klaus Kümmerer
Keyword(s):  
Aqueous Solution ◽  
Low Temperature ◽  
Penicillin G ◽  
Benzyl Penicillin ◽  
Laboratory Conditions

Multiresidue Method for Determination of Eight Neutral β-Lactam Penicillins in Milk by Fluorescence-Liquid Chromatography

1985 ◽  
Vol 68 (5) ◽  
pp. 968-971
Author(s):  
Robert K Munns ◽  
Wilbert Shimoda ◽  
Jose E Roybal ◽  
Cassandra Vieira
Keyword(s):  
Liquid Chromatography ◽  
Mobile Phase ◽  
Methylene Chloride ◽  
Side Chain ◽  
Excitation Wavelength ◽  
Benzyl Penicillin ◽  
Aqueous Fraction ◽  
Phenoxymethyl Penicillin ◽  
Hydrolysis Of

Abstract A method of determining total penicillins begins with an enzymatic hydrolysis of the (J-Iactam ring to form their respective penicilloate product. Acetonitrile precipitates much of the casein and protein, which are then separated from the liquid by centrifugation. The lipids are removed from the aqueous fraction with methylene chloride. Mercuric chloride is added, which reacts with the penicilloate to liberate the side chain that has a terminal aldehyde. These penilloaldehyde products are extracted with methylene chloride and are subsequently reacted with dansyl hydrazine. The resulting fluorolabeled side chains are separated by liquid chromatography on a C18 column with acetonitrile- water as mobile phase. The fluorescence is measured by the mercury line at 254 nm excitation wavelength and a 500 nm filter on the emission side. The overall average recoveries from milk spiked at 25, 50, and 100 ppb are benzyl penicillin 79.4%; phenoxymethyl penicillin 59.7%; phenethicillin 75.9%; nafcillin 87.7%; methacillin 47.5%; oxacillin 57.6%; cloxicillin 37.3%; and dicloxicillin 26.4%.

scholarly journals Reversible inhibitors of penicillinases

1978 ◽  
Vol 169 (1) ◽  
pp. 197-204 ◽  
Author(s):  
P A Kiener ◽  
S G Waley
Keyword(s):  
Boric Acid ◽  
Boronic Acid ◽  
Resonance Spectroscopy ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Benzyl Penicillin ◽  
Phenoxymethyl Penicillin ◽  
Reversible Inhibitors ◽  
Competitive Inhibitors ◽  
Lactam Ring

Reversible competitive inhibitors of a penicillinase, beta-lactamase 1 from Bacillus cereus, were studied. These represent the first inhibitors of a penicillinase that lack the beta-lactam ring. The products of the enzymic reaction, namely penicilloic acids, are inhibitors; their decarboxylation products, the penilloic acids, are also inhibitors, and have somewhat lower Ki values. Inhibitors have been prepared from benzylpenicillin, phenoxymethyl-penicillin, methicillin (2,6-dimethoxybenzamidopenicillanic acid) and 3-hydroxy-4-nitrobenzamidopenicillanic acid. Decarboxylation of the penicilloic acids from benzyl-penicillin, or from phenoxymethylpenicillin, leads to epimerization (at C-5) of the penilloic acid. Nuclear-magnetic resonance spectroscopy at a frequency of 270 MHz can distinguish the epimers. Other competitive inhibitors studied were boric acid, benzene boronic acid and m-aminobenzeneboronic acid. Boric acid itself was the best inhibitor of beta-lactamase I so far found.

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