Experimental Studies on Elimination of Microbial Contamination by Hydroxyl Radicals Produced by Strong Ionization Discharge

2008 ◽  
Vol 10 (4) ◽  
pp. 463-465 ◽  
Author(s):  
Bai Mindong ◽  
Zhang Zhitao ◽  
Zhao Dongyan ◽  
Yang Bo
Keyword(s):  
Hydroxyl Radicals ◽  
Microbial Contamination ◽  
Experimental Studies ◽  
Strong Ionization Discharge

Study of Removing Bacteria and Microcystis aeruginosa by Hydroxyl Radical

2013 ◽  
Vol 864-867 ◽  
pp. 418-421
Author(s):  
Wei Xu ◽  
Rong Jie Yi ◽  
Jing Jing Li ◽  
Jin De Song ◽  
Chen Wu Yi ◽  
...  
Keyword(s):  
Hydroxyl Radical ◽  
Microcystis Aeruginosa ◽  
Large Scale ◽  
Microbial Contamination ◽  
Treatment Process ◽  
Treatment Time ◽  
Ph Value ◽  
High Concentration ◽  
Initial Ph ◽  
Strong Ionization Discharge

The 1.5t/h algae and bacteria wastewater with high concentration was treated by hydroxyl radical (OH) produced by a strong ionization discharge. In this paper, the feasibility of kill bacteria and alga by OH was investigated, and effects of OH concentration, treatment time and pollution initial concentration on degrading microorganisms by OH were investigated in detail. The results indicated that the treatment process was effective in the degradation of the bacteria and alga at the initial pH value of 7.1, OH dosage of 2.33mg/L, the initial microcystis aeruginosa concentration of 106/mL and the initial bacterial dosage of 106cfu/mL, the bacteria and alga degradation rate reached 99.99% at 303K after 15min treatment. The results provided a theoretical basis for the OH treatment of microbial contamination in drinking water in large-scale.

scholarly journals Study of microbiological purity with myramistin, anesthezine and CO2 extract of chamomile for use in surgical practice

2019 ◽  
pp. 80-89
Author(s):  
L. L. Davtian ◽  
O. P. Shmatenko ◽  
V .A. Tarasenko ◽  
O. M. Vlasenko ◽  
G. V. Osedlo ◽  
...  
Keyword(s):  
Membrane Filtration ◽  
Microbial Contamination ◽  
Raw Materials ◽  
Experimental Studies ◽  
Dosage Forms ◽  
Negative Control ◽  
The State ◽  
Biological Study ◽  
Aerobic Bacteria ◽  
Bacteria And Fungi

Any finished dosage forms, including soft dosage forms, are subject to microbial contamination. It can be caused by microbial contamination of plant-based medicinal raw materials, air, industrial premises, equipment, utensils, water, personnel’s hands, general non-compliance with the sanitary and epidemic regime of production, etc. The aim of the study was to conduct a biological study of the developed cream with Miramistin, anesthesin and CO2 chamomile extract in terms of “microbiological purity” in accordance with the requirements of the State Pharmacopoeia of Ukraine. The object of the study was CO2 chamomile extract, anesthesin, miramistin, emulsifiers, the developed cream. Quantitative determination of the colony forming units of test microorganisms in suspensions was carried out by hanging in Petri dishes with soybean casein agar for bacteria and Saburo medium for fungi. Studies of the microbiological purity of the investigated samples of the cream were carried out in accordance with the requirements of the State Pharmacopoeia of Ukraine 1 ed., Paragraph 5.1.4.. Tests were performed using the direct sowing method. The assessment of the degree of microbial contamination of the investigated creams samples consisted of determining the total number of aerobic bacteria and fungi in 1.0 g of the sample, as well as the absence of bacteria of the family Enterobacteriaceae, St. aureus and Ps. aeruginosa. To verify the study conditions, a negative control study was performed using a sterile solvent for hanging on nutrient media. On the basis of experimental studies, it was found that the optimum method is membrane filtration for determining the total number of viable aerobic bacteria, and for fungi, the direct hanging method. In the course of the experiment, it was established that the total number of viable aerobic microorganisms is less than 100, and yeast and mold fungi are less than 10 per 1 g of each sample; St. aureus and Ps. aeruginosa and some other gram-negative bacteria are not defined, which meets the requirements of the State Pharmacopoeia of Ukraine.

scholarly journals Daylight-Active Cellulose Nanocrystals Containing Anthraquinone Structures

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3547
Author(s):  
Yiwen Zhu ◽  
Audrey Sulkanen ◽  
Gang-Yu Liu ◽  
Gang Sun
Keyword(s):  
Reactive Oxygen Species ◽  
Hydroxyl Radicals ◽  
Cellulose Nanocrystals ◽  
Microbial Contamination ◽  
Structural Integrity ◽  
Oxygen Species ◽  
Significant Interest ◽  
Carrier Materials ◽  
Application Requirements ◽  
High Degree

Antimicrobial and antiviral materials have attracted significant interest in recent years due to increasing occurrences of nosocomial infections and pathogenic microbial contamination. One method to address this is the combination of photoactive compounds that can produce reactive oxygen species (ROS), such as hydrogen peroxide and hydroxyl radicals to disinfect microbes, with carrier materials that meet the application requirements. Using anthraquinone (AQ) and cellulose nanocrystals (CNCs) as the photoactive and carrier components, respectively, this work demonstrated the first covalent incorporation of AQ onto CNCs. The morphology and the photoactive properties were investigated, revealing the structural integrity of the CNCs and the high degree of photoactivity of the AQ-CNC materials upon UVA exposure. The AQ-CNCs also exhibited an unexpected persistent generation of ROS under darkness, which adds advantages for antimicrobial applications.

scholarly journals Study of the efficacy of antimicrobial preservatives in justifying the composition of a dermatological gel with a phytocomplex

2021 ◽  
Vol 14 (3) ◽  
pp. 306-313
Author(s):  
V. S. Myrhorod ◽  
O. H. Bashura ◽  
O. P. Strilets ◽  
S. H. Bobro ◽  
L. S. Strelnykov
Keyword(s):  
Benzoic Acid ◽  
Microbial Contamination ◽  
Sorbic Acid ◽  
Raw Materials ◽  
Experimental Studies ◽  
Antimicrobial Efficacy ◽  
Potassium Sorbate ◽  
Medicinal Products ◽  
Average Value ◽  
Antimicrobial Substances

The microbiological stability of medicinal products always requires close attention during the pharmaceutical development phase, as microbial contamination can pose a threat to both the health of the patient and the stability of the medicinal product. The level of microbial contamination can be controlled by monitoring the quality of raw materials, compliance with appropriate sanitation of production facilities and equipment, the use of scientifically justified preservatives in the drug. The aim of the work is to substantiate the use of a preservative and its concentration in the composition of the developed gel with phytocomplex. Materials and methods. The objects of the study were gel samples with the addition of a preservative: Euxyl 9010K (90 % phenoxyethanol, 10 % ethylhexylglycerol), methyl parahydroxybenzoate (E218), sorbic acid, potassium sorbate, benzoic acid. Concentrations of antimicrobial substances used corresponded to their average value from the range of used concentrations. The research has used the method of evaluating the effectiveness of antimicrobial preservatives, given in SPU 2.0. Results. Experimental studies using preservatives Euxyl 9010K 0.60 %, methyl parahydroxybenzoate 0.25 %, sorbic acid 0.10 %, potassium sorbate 0.25 %, benzoic acid 0.15 % in the samples of the developed gel with phytocomplex had shown that the obtained results for all samples fully meet the requirements of SPU in terms of “antimicrobial efficacy of preservatives” for topical drugs. According to the results of the first stage of research, it had been found that the greatest antimicrobial efficacy was shown by a sample with the preservative Euxyl 9010K. The subject of the second stage of research was the substantiation of the concentration of Euxyl 9010K (0.45 %, 0.60 %, and 0.75 %) based on the results of which it had been established that the gel samples with concentrations of Euxyl 9010K 0.60 % and 0.75 % met the requirements of SPU on the indicator of “antimicrobial efficacy of preservatives” for topical medicinal products. The sample with a concentration of Euxyl 9010K 0.45 % also met these requirements, but the logarithm of the reduction in the number of viable cells of Pseudomonas aeruginosa bacteria after 2 days of storage is 2.00, which was the limit value according to the requirements of SPU. Conclusions. The expediency of using Euxyl 9010K (90 % phenoxyethanol, 10 % ethylhexylglycerol) at a concentration of 0.60 % as a preservative had been experimentally substantiated.

3-D reconstruction and analysis of mammalian mitotic spindle structure

1992 ◽  
Vol 50 (1) ◽  
pp. 578-579
Author(s):  
Kent McDonald ◽  
David Mastronarde ◽  
Rubai Ding ◽  
Eileen O'Toole ◽  
J. Richard McIntosh
Keyword(s):  
Cross Sections ◽  
Mitotic Spindle ◽  
Experimental Studies ◽  
Video Camera ◽  
Three Dimensions ◽  
Mitotic Spindles ◽  
Black And White ◽  
Reconstruction Methods ◽  
Spindle Structure ◽  
Tissue Culture Line

Mammalian spindles are generally large and may contain over a thousand microtubules (MTs). For this reason they are difficult to reconstruct in three dimensions and many researchers have chosen to study the smaller and simpler spindles of lower eukaryotes. Nevertheless, the mammalian spindle is used for many experimental studies and it would be useful to know its detailed structure.We have been using serial cross sections and computer reconstruction methods to analyze MT distributions in mitotic spindles of PtK cells, a mammalian tissue culture line. Images from EM negatives are digtized on a light box by a Dage MTI video camera containing a black and white Saticon tube. The signal is digitized by a Parallax 1280 graphics device in a MicroVax III computer. Microtubules are digitized at a magnification such that each is 10-12 pixels in diameter.

Effects of Attachment Styles on the Experience of Equity in Heterosexual Couples Relationships

2003 ◽  
Vol 50 (4) ◽  
pp. 298-310 ◽  
Author(s):  
Ina Grau ◽  
Jörg Doll
Keyword(s):  
Attachment Theory ◽  
Attachment Style ◽  
Intimate Relationships ◽  
Attachment Styles ◽  
Experimental Studies ◽  
The Other ◽  
Heterosexual Couples ◽  
Secure Attachment ◽  
Dependent Variables ◽  
Equity Ratio

Abstract. Employing one correlational and two experimental studies, this paper examines the influence of attachment styles (secure, anxious, avoidant) on a person’s experience of equity in intimate relationships. While one experimental study employed a priming technique to stimulate the different attachment styles, the other involved vignettes describing fictitious characters with typical attachment styles. As the specific hypotheses about the single equity components have been developed on the basis of the attachment theory, the equity ratio itself and the four equity components (own outcome, own input, partner’s outcome, partner’s input) are analyzed as dependent variables. While partners with a secure attachment style tend to describe their relationship as equitable (i.e., they give and take extensively), partners who feel anxious about their relationship generally see themselves as being in an inequitable, disadvantaged position (i.e., they receive little from their partner). The hypothesis that avoidant partners would feel advantaged as they were less committed was only supported by the correlational study. Against expectations, the results of both experiments indicate that avoidant partners generally see themselves (or see avoidant vignettes) as being treated equitably, but that there is less emotional exchange than is the case with secure partners. Avoidant partners give and take less than secure ones.

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