The effect of synthesized Cu2O on the microbial corrosion inhibition of urban concrete sewer systems

The microbial corrosion of reinforced concrete sewers was inhibited by synthesized cuprous oxide (Cu2O) nanoparticles. The antibacterial characteristics of Cu2O on Acidithiobacillus thiooxidans were investigated by temporal variation of pH, turbidity, and bacterial counting. Three reinforced concrete samples with different weight percentages of electrodeposited Cu2O (0.06 wt%, 0.055 wt %, 0.05 wt %) were used. The bacterial counting showed that the number of bacteria in samples with 0.06, 0.055, and 0.05 wt% of Cu2O was 4.82, 4.42, and 2.94 times lower than the blank sample (BS), respectively. After bacterial growth, the optical density measurement showed that the percentage of turbidity enhancement for samples with 0.06, 0.055, and 0.05 wt% of Cu2O were 108%, 118%, 165%, respectively, while it was 412% for the BS. Moreover, the pilot stage's pH monitoring revealed that the electrodeposited Cu2O lowered the concentration of hydronium between 7 to 81 times compared to the BS. Experiments indicated that slight changes in the amount of electrodeposited Cu2O lead to significant changes in samples' ability to hinder bacterial growth and microbial-induced corrosion.

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Improvement in Metal Recovery from Laterite Tailings by Bioleaching

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.71-73.489 ◽

2009 ◽

Vol 71-73 ◽

pp. 489-492 ◽

Cited By ~ 2

Author(s):

Ianeya Hernández Díaz ◽

Federico Galizia ◽

Orquidea Coto ◽

Edgardo R. Donati

Keyword(s):

Sulphuric Acid ◽

Bacterial Growth ◽

Low Ph ◽

Metal Recovery ◽

Pulp Density ◽

Acidithiobacillus Thiooxidans ◽

Ph Values ◽

Technology Process ◽

High Nickel

In previous studies it has been showed that sulphuric bio-acid is a good leaching agent for laterite tailings. In this work we evaluated nickel and cobalt recoveries from tailings of Caron technology process using sulphuric acid produced by Acidithiobacillus thiooxidans cultures under different conditions. In studies where tailings were initially added to the cultures, high nickel and cobalt recoveries (about 60 % for cobalt and 85-100 % for nickel) were reached after 13 days when low pulp densities (1 % and 2.5 %) of laterite tailings were used. These high recoveries fitted very well with the low pH values measured in these cultures. However, metal recoveries were negligible when higher pulp densities were used. Due to such reason, the performance of pre-cultivation configuration was evaluated; for that laterite tailings were added to the cultures after 24 or 48 hours of bacterial growth. This configuration was very efficient even at high pulp density (like 10 %) reaching recoveries (almost 50 % for cobalt and 80 % for nickel) close to those observed where tailings at low pulp densities were initially added to the cultures.

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Effect of a UV-C Automatic Last-Generation Mobile Robotic System on Multi-Drug Resistant Pathogens

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182413019 ◽

2021 ◽

Vol 18 (24) ◽

pp. 13019

Author(s):

Carla Russo ◽

Desirée Bartolini ◽

Cristina Corbucci ◽

Anna Maria Stabile ◽

Mario Rende ◽

...

Keyword(s):

Bacterial Growth ◽

Irradiation Effect ◽

Healthcare Associated Infections ◽

Drug Resistant ◽

Mortality And Morbidity ◽

Disinfection Methods ◽

Healthcare Associated ◽

Uv C ◽

Number Of Bacteria

Background: Healthcare-associated infections caused by multi-drug resistant (MDR) pathogens are associated with increased mortality and morbidity among hospitalized patients. Inanimate surfaces, and in particular high-touch surfaces, have often been described as the source for outbreaks of nosocomial infections. The present work aimed to evaluate the efficacy of a last-generation mobile (robotic) irradiation UV-C light device R2S on MDR microorganisms in inanimate surfaces and its translation to hospital disinfection. Methods: The efficacy of R2S system was evaluated in environmental high-touch surfaces of two separate outpatient rooms of Perugia Hospital in Italy. The static UV-C irradiation effect was investigated on both the bacterial growth of S. aureus, MRSA, P. aeruginosa, and K. pneumoniae KPC and photoreactivation. The antimicrobial activity was also tested on different surfaces, including glass, steel, and plastic. Results: In the environmental tests, the R2S system decreased the number of bacteria, molds, and yeasts of each high-touch spot surface (HTSs) compared with manual sanitization. UV-C light irradiation significantly inhibits in vitro bacterial growth, also preventing photoreactivation. UV-C light bactericidal activity on MDR microorganisms is affected by the type of materials of inanimate surfaces. Conclusions: The last-generation mobile R2S system is a more reliable sanitizing procedure compared with its manual counterpart.

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The Number of Bacteria, Antioxidant Capacity, and Organoleptic Properties of Red Ginger Fried Chicken

Bulletin of Culinary Art and Hospitality ◽

10.17977/um069v1i12021p1-6 ◽

2021 ◽

Vol 1 (1) ◽

pp. 1-6

Author(s):

Lismi Animatul Chisbiyah ◽

Mazarina Devi ◽

Issutarti Issutarti

Keyword(s):

Antioxidant Capacity ◽

Factorial Design ◽

Experimental Research ◽

Bacterial Growth ◽

Organoleptic Properties ◽

Red Ginger ◽

Alpinia Purpurata ◽

Number Of Bacteria ◽

Range Test

Alpinia purpurata (Vieill.) K. Schum is a spice that has the ability to inhibit bacterial growth and has a good antioxidant capacity. This study aims to determine the effect of adding Alpinia purpurata (Vieill.) K. Schum 0%, 10%, 20%, 30%, 40% on day 0, 1, and 2 on the number of bacteria, antioxidant capacity and hedonic properties which include the taste, aroma, and color of Red ginger fried chicken. This type of research was an experimental research with a completely randomized factorial design (CRD). The data obtained were then analyzed statistically using ANOVA and continued with Duncan's Multiple Range Test (DMRT) to obtained differences. Each treatment was repeated twice. The results showed that the addition of the concentration of Alpinia purpurata (Vieill.) K. Schum 0%, 10%, 20%, 30% and 40% in Red ginger fried chicken had a significant effect on the number of bacteria and antioxidant capacity on day 0, 1, 2 and had a significant effect on the hedonic properties on day 0. (taste, color and aroma) on the hedonic properties on day 0. (taste, color and aroma). The addition of Alpinia purpurata (Vieill.) K. Schum 40% gave the best results on the number of bacteria, antioxidant capacity and hedonic properties. To conclude, the higher the addition of Alpinia purpurata (Vieill.) K. Schum to Red ginger fried chicken resulted on the lower the number of bacteria and the greater the antioxidant capacity and the more preferred hedonic properties.

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Novel Electrochemical Sensors Based on Cuprous Oxide-Electrochemically Reduced Graphene Oxide Nanocomposites Modified Electrode toward Sensitive Detection of Sunset Yellow

Molecules ◽

10.3390/molecules23092130 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2130 ◽

Cited By ~ 12

Author(s):

Quanguo He ◽

Jun Liu ◽

Xiaopeng Liu ◽

Yonghui Xia ◽

Guangli Li ◽

...

Keyword(s):

Graphene Oxide ◽

Cuprous Oxide ◽

Anodic Peak ◽

Enhancement Effect ◽

Sunset Yellow ◽

Synergistic Enhancement ◽

Reduced Graphene ◽

Electrochemically Reduced Graphene Oxide ◽

Cu2o Nanoparticles

Control and detection of sunset yellow is an utmost demanding issue, due to the presence of potential risks for human health if excessively consumed or added. Herein, cuprous oxide-electrochemically reduced graphene nanocomposite modified glassy carbon electrode (Cu2O-ErGO/GCE) was developed for the determination of sunset yellow. The Cu2O-ErGO/GCE was fabricated by drop-casting Cu2O-GO dispersion on the GCE surface following a potentiostatic reduction of graphene oxide (GO). Scanning electron microscope and X-ray powder diffractometer was used to characterize the morphology and microstructure of the modification materials, such as Cu2O nanoparticles and Cu2O-ErGO nanocomposites. The electrochemical behavior of sunset yellow on the bare GCE, ErGO/GCE, and Cu2O-ErGO/GCE were investigated by cyclic voltammetry and second-derivative linear sweep voltammetry, respectively. The analytical parameters (including pH value, sweep rate, and accumulation parameters) were explored systematically. The results show that the anodic peak currents of Cu2O-ErGO /GCE are 25-fold higher than that of the bare GCE, due to the synergistic enhancement effect between Cu2O nanoparticles and ErGO sheets. Under the optimum detection conditions, the anodic peak currents are well linear to the concentrations of sunset yellow, ranging from 2.0 × 10−8 mol/L to 2.0 × 10−5 mol/L and from 2.0 × 10−5 mol/L to 1.0 × 10−4 mol/L with a low limit of detection (S/N = 3, 6.0 × 10−9 mol/L). Moreover, Cu2O-ErGO/GCE was successfully used for the determination of sunset yellow in beverages and food with good recovery. This proposed Cu2O-ErGO/GCE has an attractive prospect applications on the determination of sunset yellow in diverse real samples.

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Synthesis and Investigation of Antimicrobial Activity of Cu2O Nanoparticles/Zeolite

Journal of Nanoparticles ◽

10.1155/2017/7056864 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 12

Author(s):

Bui Duy Du ◽

Dang Van Phu ◽

Le Anh Quoc ◽

Nguyen Quoc Hien

Keyword(s):

Electron Microscopy ◽

Cuprous Oxide ◽

Large Scale ◽

Copper Ions ◽

Zeolite A ◽

X Ray Diffraction ◽

X Ray ◽

Agricultural Application ◽

Transmission Electron ◽

Cu2o Nanoparticles

Cuprous oxide (Cu2O) nanoparticles in zeolite A were synthesized by two steps: (i) ion-exchange of copper ions into the zeolite and (ii) reduction of copper ions in cages of the zeolite by hydrazine hydrate in base medium. The Cu2O nanoparticles/zeolite product was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The particle size of Cu2O nanoparticles was of 40 nm. The antibacterial activity of the as-synthesized Cu2O nanoparticles/zeolite against Escherichia coli was also investigated. Cu2O NPs/zeolite product can be favorably produced on large scale for water treatment and agricultural application as antimicrobial agent.

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The conformability of two equations for bacterial growth in pork

Czech Journal of Food Sciences ◽

10.17221/3512-cjfs ◽

2011 ◽

Vol 20 (No. 2) ◽

pp. 69-73

Author(s):

M. Miyahara ◽

T. Matsumoto ◽

H. Sakurai ◽

P. Pipek

Keyword(s):

Exponential Function ◽

Bacterial Growth ◽

Growth Curve ◽

Salt Solution ◽

Functional Equations ◽

Physiological Salt Solution ◽

Initial Number ◽

Natural Logarithm ◽

Number Of Bacteria

Pork is now distributed as cut meat, which increases the chance of contamination with bacteria. The rate of bacterial growth can be expressed by an exponential function. In order to find how the number of contaminating bacteria increases, we compared two functional equations for a growth curve. They are logistic: Yt = K (1 + m e–at) (1) and Gompertz: log Yt = log K + (log a)bt (2) equations (where Yt = the number of bacteria at the time t in min, m and a = coefficient, e = natural logarithm, K maximum number of bacteria). 90 ml of physiological salt solution was added to 10 g of pork. It was homogenized for 3 min, then incubated at 35°C for 13 hrs. The number of bacteria was counted every hour. We found from these data that the above two equations can be expressed as follows: Yt = 23 535 (1 + 16269 e–1.1608t) and log Yt = 8.9940 + (–3.1124) × 0.7839t. The theoretical and actual values matched well in equation (1), and the number of bacteria can be predicted accurately using this equation at a given time after incubation. The theoretical and actual values did not match well in equation (2) and its accuracy to predict the number of bacteria was very low except the initial number of bacteria was high.  

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Synthesis, Characterizations and Antimicrobial Activity of Cuprous Oxide (Cu2O) Nanoparticles

Journal of Nepal Chemical Society ◽

10.3126/jncs.v40i0.27271 ◽

2019 ◽

Vol 40 ◽

pp. 5-10

Author(s):

Amrit Regmi ◽

Janak Bhandari ◽

Sitaram Bhattarai ◽

Surendra K. Gautam

Keyword(s):

Electron Microscopy ◽

Staphylococcus Aureus ◽

Cuprous Oxide ◽

Antimicrobial Properties ◽

Chemical Species ◽

Face Centered Cubic ◽

Bacterial Strains ◽

Gram Positive ◽

X Ray ◽

Cu2o Nanoparticles

Cuprous oxide nanoparticles were synthesized by the reduction of copper sulphate pentahydrate salt at different concentration using sodium borohydride as a reducing agent, polyethylene glycol-6000 as a stabilizer by simple, chemical co-precipitation methods and the effect of concentration on particle size were also studied. The crystalline size and phase of Cu2O nanoparticles (NPs) were authenticated by X-ray diffraction (XRD), morphology and structure by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and elemental analysis was carried out by energy-dispersive X-ray spectroscopy (EDX). The concentration-dependent antimicrobial properties of Cu2O NPs were studied for a different strain of bacteria. XRD and selected area electron diffraction studies (SAED) patterns confirmed the formation of face-centered-cubic Cu2O nanoparticles with size 4.77 nm and 8.02 nm at two different concentrations of 0.01 M and 0.1 M CuSO4, respectively. SEM and TEM images showed that the nanoparticles were uniform, in the form of clusters, and homogeneously distributed. EDX confirmed that synthesized nanoparticles were in pure form having copper and oxygen ratio 3:1 based on the atomic percentage of the chemical species. Cu2O nanoparticles showed excellent antibacterial activity against both bacterial strains Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli). The antibacterial activities of Cu2O NPs were found to be concentration-dependents and large bactericidal effect were seen for Gram-positive (Staphylococcus aureus) bacteria at higher concentrations of Cu2O NPs.

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BACTERIAL GROWTH AND MULTIPLICATION AS DISCLOSED BY MICRO MOTION PICTURES

Journal of Experimental Medicine ◽

10.1084/jem.59.3.381 ◽

1934 ◽

Vol 59 (3) ◽

pp. 381-391 ◽

Cited By ~ 5

Author(s):

Ralph W. G. Wyckoff

Keyword(s):

Life Cycle ◽

Internal Structure ◽

Motion Picture ◽

Bacterial Growth ◽

Motion Pictures ◽

Bacterial Division ◽

Micro Motion ◽

Number Of Bacteria

Using a micro motion picture technique for making records, studies covering several thousand hours of observation have been made of the growth of a number of bacteria. On the basis of these experiments a discussion is offered of bacterial division and its influence on gross colony appearance, of different kinds of pleomorphism that have been observed, and of the nature of the internal structure that is seen in some bacteria. Several of the microorganisms chosen for examination are ones that have been thought to give evidence of life cycle phenomena. The present pictures, however, contain no evidence of a bacterial cycle in the commonly accepted meaning of the term.

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