scholarly journals Studies on the Stability of Drugs in Biological Media. III. Effect of Cupric Ion on the Stability and Antibacterial Activity of Penicillins in Culture Medium

1971 ◽  
Vol 19 (4) ◽  
pp. 730-736 ◽  
Author(s):  
KIICHIRO KAKEMI ◽  
HITOSHI SEZAKI ◽  
KIKUO IWAMOTO ◽  
HIROSHI KOBAYASHI ◽  
KENICHI INUI
Keyword(s):  
Antibacterial Activity ◽  
Culture Medium ◽  
Biological Media ◽  
Cupric Ion ◽  
The Stability

scholarly journals Emphasized Mechanistic Antimicrobial Study of Biofunctionalized Silver Nanoparticles on Model Proteus mirabilis

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Asra Parveen ◽  
Manjunath S. Yalagatti ◽  
Venkataraman Abbaraju ◽  
Raghunandan Deshpande
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Activity ◽  
Proteus Mirabilis ◽  
Reducing Sugars ◽  
Radical Scavenging ◽  
Human Pathogens ◽  
Antimicrobial Study ◽  
Synthetic Procedure ◽  
Dpph Method ◽  
The Stability

Antimicrobial study of biofunctionalized silver nanoparticles has been done with the emphasis on its mechanism on both gram positive and negative bacteria. The biofunctionalized silver nanoparticles are employed considering their importance in green chemistry with respect to easy synthesis, usefulness, and economic synthetic procedure involved. The stability of these nanoparticles was determined by zeta potential analyzer. The probable mechanism of antibacterial activity was performed on Proteus mirabilis by field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDAX) study which does not show the presence of silver. The free radicals generated by silver nanoparticles were responsible for lethal antibacterial activity by rupturing the cell surface which causes improper nutrient and signal supply. Free radical scavenging efficacy of silver nanoparticles was confirmed by 1,1-Diphenyl-2-picrylhydrazyl (DPPH) method. AgNP enhanced the membrane leakage of reducing sugars by destroying the proteins existing on the cell wall. These nanoparticles are found to be toxic against human pathogens and are highly effective on Staphylococcus aureus. The effect of silver nanoparticles is concentration dependent and independent of the type of strains used.

scholarly journals The effects of low-temperature storage on the viability of Lactobacillus casei and the stability of antibacterial activity in green grass jelly synbiotic drinks

2020 ◽  
Vol 21 (8) ◽  
Author(s):  
SAMSUL RIZAL ◽  
Suharyono Suharyono ◽  
Fibra Nuariny ◽  
Julfi Restu Amelia
Keyword(s):  
Antibacterial Activity ◽  
Lactic Acid ◽  
Low Temperature ◽  
Lactic Acid Bacteria ◽  
Lactobacillus Casei ◽  
Pathogenic Bacteria ◽  
Ph Value ◽  
Low Temperature Storage ◽  
The Stability ◽  
Temperature Storage

Abstract. Rizal S, Suharyono, Nurainy F, Amela JR. 2020. The effects of low-temperature storage on the viability of Lactobacillus casei and the stability of antibacterial activity in green grass jelly synbiotic drinks. Biodiversitas 21: 3826-3831. Synbiotic drinks from green grass jelly have shown antibacterial activity against pathogenic bacteria. These are usually stored at low temperatures to maintain their characteristics. The aim of this study was to determine the effect of storage at low temperature of 10°C on the viability of lactic acid bacteria (Lactobacillus casei) and the stability of the antibacterial activity in synbiotic drinks made of green grass jelly. Antibacterial activity of green grass jelly synbiotic drink was conducted against pathogenic bacteria (Staphylococcus aureus, Salmonella sp., Bacillus cereus, and Escherichia coli). The products were stored for 28 days at 10°C temperature. Observations on the antibacterial activity, pH value, total acid, and total lactic acid bacteria were carried out every 7 days. Antibacterial activity was evaluated using agar well diffusion method. The results showed that storage at low temperature (10 ± 2°C) for 28 days decreased the antibacterial activity and pH value but sharply increased total lactic acid bacteria (at 0 to 7 days of storage) in green grass jelly synbiotic drinks. Salmonella sp. showed the highest inhibition caused by the antibacterial agents in green grass jelly synbiotic drinks while the lowest inhibition was found on Staphylococcus aureus. During storage at low temperature, green grass jelly synbiotic drinks had a total of lactic acid bacteria that ranged from 9.51 to 10.10 (Log CFU/mL) or equal to 3.24x109-1.26x1010 CFU/mL; a total of lactic acid that ranged from 0.48% to 0.87%; and pH values that ranged from 3.78 to 4.08.

The chemical stability of mendipite, diaboleïte, chloroxiphite, and cumengéite, and their relationships to other secondary lead(II) minerals

1980 ◽  
Vol 43 (331) ◽  
pp. 901-904 ◽  
Author(s):  
D. Alun Humphreys ◽  
John H. Thomas ◽  
Peter A. Williams ◽  
Robert F. Symes
Keyword(s):  
Chloride Ion ◽  
Stability Diagram ◽  
Chloride Ions ◽  
Ion Concentration ◽  
Stability Field ◽  
Cupric Ion ◽  
Free Energy Of Formation ◽  
High Concentrations ◽  
The Stability ◽  
Ph Range

SummaryThe chemical stabilities of mendipite, Pb3O2Cl2, diaboleïte, Pb2CuCl2(OH)4, chloroxiphite, Pb3CuCl2O2(OH)2, and cumengéite, Pb19Cu24Cl42 (OH)44, have been determined in aqueous solution at 298.2 K. Values of standard Gibbs free energy of formation, ΔGf°, for the four minerals are −740, −1160, −1129, and −15163±20 kJ mol−1 respectively. These values have been used to construct the stability diagram shown in fig. I which illustrates their relationships to each other and to the minerals cotunnite, PbCl2, paralaurionite, PbOHCl, and litharge, PbO. This diagram shows that mendipite occupies a large stability field and should readily form from cold, aqueous, mineralizing solutions containing variable amounts of lead and chloride ions, and over a broad pH range. The formation of paralaurionite and of cotunnite requires a considerable increase in chloride ion concentration, although paralaurionite can crystallize under much less extreme conditions than cotunnite. The encroachment of the copper minerals on to the stability fields of those mineral phases containing lead(II) only is significant even at very low relative activities of cupric ion. Chloroxiphite has a large stability field, and at given concentrations of cupric ion, diaboleïte is stable at relatively high aCl−. Cumengéite will only form at high concentrations of chloride ion.

scholarly journals A tutorial for the assessment of the stability of organometallic complexes in biological media

2020 ◽  
Vol 906 ◽  
pp. 121059 ◽  
Author(s):  
Sarah Keller ◽  
Yih Ching Ong ◽  
Yan Lin ◽  
Kevin Cariou ◽  
Gilles Gasser
Keyword(s):  
Organometallic Complexes ◽  
Biological Media ◽  
The Stability

The Influence of Different Concentration of Glucose on the Growth of Recombinant E.coli and Plasmid Stability

2013 ◽  
Vol 647 ◽  
pp. 185-189
Author(s):  
Ying Qian Xu ◽  
Chun Yuan Liu ◽  
Feng Ju Cai ◽  
Jun Yi Hu
Keyword(s):  
Culture Medium ◽  
Plasmid Stability ◽  
Biomass Concentration ◽  
Optimal Concentration ◽  
Good For ◽  
The Stability ◽  
Recombinant E.Coli

In this paper, the plasmid stability and the concentration of recombinant E.coli DH5α were investigated by adding glucose of different concentration at the beginning of fermentation. The result shows that glucose was good for the growth of recombinant E.coli DH5α and the stability of plasmid. The optimal concentration of glucose was 1g/L. The biomass concentration could be up to110.930g/L and the fraction of plasmid-carrying cell was about 99% in the optimized culture medium.

Investigation of the stability of magnetite nanoparticles functionalized with catechol based ligands in biological media

2012 ◽  
Vol 22 (47) ◽  
pp. 24909 ◽  
Author(s):  
Steven L. Saville ◽  
Roland C. Stone ◽  
Bin Qi ◽  
O. Thompson Mefford
Keyword(s):  
Magnetite Nanoparticles ◽  
Biological Media ◽  
The Stability

scholarly journals The study of antibacterial activity and stability of dyed cotton fabrics modified with different forms of silver

2012 ◽  
Vol 77 (2) ◽  
pp. 225-234 ◽  
Author(s):  
Vesna Lazic ◽  
Zoran Saponjic ◽  
Vesna Vodnik ◽  
Suzana Dimitrijevic ◽  
Petar Jovancic ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Activity ◽  
Active Component ◽  
Silver Chloride ◽  
Cotton Fabrics ◽  
Negative Bacterium ◽  
Positive Bacterium ◽  
Vat Dyes ◽  
Artificial Sweat ◽  
The Stability

This study compares the effect of colloidal silver nanoparticles and commercial RUCO-BAC AGP agent with silver chloride as an active component on antibacterial activity of dyed cotton fabrics. Cotton fabrics were dyed with vat dyes Bezanthren olive T and Bezanthren grey FFB. Antibacterial activity of silver loaded dyed cotton fabrics was tested against Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Escherichia coli. Unlike RUCO-BAC AGP synthesized silver nanoparticles deposited onto dyed cotton fabrics provided maximum bacteria reduction independently of applied dye. The stability of modified cotton fabrics was analyzed in artificial sweat at pH 5.5 and 8.0. Approximately the same amount of silver was released from differently modified cotton fabrics in artificial sweat. Larger amount of silver was released in the sweat at pH 8.0.

Biological Markers: Their Use in Quantitative Assessments

1994 ◽  
Vol 8 (1) ◽  
pp. 92-99 ◽  
Author(s):  
M.F. Vine
Keyword(s):  
Biological Markers ◽  
Epidemiologic Study ◽  
Biological Marker ◽  
Cost Effective ◽  
Early Response ◽  
Biological Media ◽  
Sequence Of Events ◽  
Effective Manner ◽  
The Stability ◽  
Sensitivity Specificity

Biological markers can be conceptualized in terms of categories of markers that form a continuum representing a sequence of events from exposure to disease. These categories include markers of internal dose, biologically effective dose, early response, and disease. Outside of this sequence are susceptibility factors that can act at any point along the way to modify the effects of external exposures on disease outcomes. Examples of the use of these different types of markers in epidemiologic research are provided. There are many factors that one must consider when selecting a biological marker for use in an epidemiologic study. These factors include: the objectives of the study, the availability and specificity of potential markers, the feasibility of measuring the markers in various biological media, the invasiveness of the techniques necessary to measure the markers, the amount of biological specimen needed for analysis, the time to appearance of the markers in the biological media, the persistence of the markers in biological media, the variability of marker levels within and between individuals, the stability of markers in storage, as well as the cost, sensitivity, specificity, and reliability of the assays used to measure the markers. Each of these characteristics is discussed. The usefulness of biological markers in an epidemiologic study depends on the objectives of the study and whether the properties of the markers fulfill the objectives of the study in a feasible and cost-effective manner.

Sign in / Sign up

Export Citation Format

Share Document