Inhibition of Alga Contamination in Open-Culture Under Silicon Stress

2020 ◽  
Vol 14 (2) ◽  
pp. 227-233
Author(s):  
Guican Bi ◽  
Changhua Shang ◽  
Jun Xie
Keyword(s):  
Cell Growth ◽  
Silicon Content ◽  
The Other ◽  
Optimal Conditions ◽  
High Concentration ◽  
Silicate Concentration ◽  
Competition Advantage ◽  
Lipid Yield ◽  
Initial Ph ◽  
Microalgae Growth

Alga contamination was a major problem in microalgae open cultivation. The objective of this study was to estimate the effect of silicon on microalgae growth by mixed-culture experiments with four different microalgae. The results showed that under the osmotic pressure caused by high concentration of Na2SiO3, Navicula sp. N6 had a competition advantage of absorbing nutrient compared with the other three microalgae. The impacts (initial pH, nitrogen content, and silicon content) on cell growth and lipid accumulation were investigated by response surface analysis and the biomass and lipid content increased from 1.01 g/L and 10.98% to 1.33 g/L and 20.04% under the optimal conditions, with lipid yield raised from 110.90 mg/L to 266.53 mg/L. Comparison on the growth under optimum and silicon deficiency condition indicated that silicon played an important role on the growth of Navicula sp. N6 and algal contamination in diatom open scale cultivation could be solved by regulating the sodium silicate concentration.

scholarly journals Survival of Escherichia coli 0157:H7 in cultured butter during storage.

2018 ◽  
Vol 53 (2) ◽  
pp. 147
Author(s):  
A. GOVARIS (Α. ΓΚΟΒΑΡΗΣ) ◽  
D. K. PAPAGEORGIOU (Δ.Κ. ΠΑΠΑΓΕΩΡΓΙΟΥ) ◽  
K. PAPATHEODOROU (Κ. ΠΑΠΑΘΕΟΔΩΡΟΥ)
Keyword(s):  
Escherichia Coli ◽  
The Other ◽  
High Concentration ◽  
E Coli ◽  
High Inoculum ◽  
Initial Ph

The survival of E. coli 0157:H7 was examined in 3 types of butter: unsalted, salted with 0.46% and 0.93% salt. The butter samples were inoculated with a low (c.a. 3.14 log CFU/g) or high concentration (c.a. 4.80 log CFU/g) inoculum of the pathogen and were stored at 4°C and 12°C. The contaminated butter samples were stored for 2 months at 4°C and up to visible spoilage (20-26 days) at 12° C. By the end of the storage at 4°C, the tests with the high inoculum of the pathogen revealed that populations of E. coli 0157:H7 were decreased by 2.26 log CFU/g in the unsalted and in 0.46% salted types of butter, and by 2.74 log CFU/g in the 0.93% salted type of butter, while the tests with the low inoculum of the pathogen revealed that populations of E. coli Ol57:H7 decreased by 1.81 log CFU/g in the unsalted type of butter and were detectable in the other types of butter only after enrichment. By the end of the storage at 12°C, the tests with the high inoculum of the pathogen revealed that populations of E coli Ol57:H7 decreased by 2.71 and 3.17 log CFU/g in the unsalted and 0.46% salted types of butter, after 20 and 22 days, respectively and were detectable, in the 0.93% salted type of butter after 26 days, only after enrichment, while the tests with the low inoculum of the pathogen revealed that populations of E. coli O l 57:H7 were decreased by 1.88 log CFU/g in the unsalted type of butter after 20 days, and were detectable, in the 0.46% and 0.93% salted types of butter after 22 and 24 days, respectively, only after enrichment. The initial pH of all butter samples (5.18±0.01) decreased slightly (0.06-0.10) during storage at 4°C, and more (0.48 - 0.54) during storage at 12°C.

Assessment of micro and macro nutrients in poultry feeds available in Dhaka city, Bangladesh.

2017 ◽  
Vol 1 ◽  
pp. 264
Author(s):  
Md Didarul Islam ◽  
Ashiqur Rahaman ◽  
Fahmida Jannat
Keyword(s):  
Heavy Metals ◽  
Adverse Effect ◽  
The Other ◽  
Nutrient Level ◽  
Dhaka City ◽  
Toxic Heavy Metals ◽  
High Concentration ◽  
Low Concentration ◽  
Feed Formulation ◽  
Macro Nutrients

This study was based on to determine the concentration of macro and micro nutrients as well as toxic and nontoxic heavy metals present in the chicken feed available in Dhaka city of Bangladesh. All macro nutrients, if present in the feed at high concentration have some adverse effect, at the same time if this nutrient present in the feed at low concentration this have some adverse effect too. So that this nutrient level should be maintained at a marginal level. On the other side toxic heavy metals if present in the feed at very low concentration those can contaminate the total environment of the ecosystem. In this study six brand samples (starter, grower, finisher and layer) which was collected from different renowned chicken feed formulation industry in Bangladesh. Those samples were prepared for analysis by wet ashing and then metals were determined by Atomic Absorption Spectroscopy. It was found that 27.7 to 68.4, 57.3 to 121.9, 0.21 to 4.1, 0.32 to 2.1, 0.11 to 1.58, 0.28 to 2.11 and 0.28 to 1.78 for zinc, iron, copper, mercury, cadmium, nickel and cobalt respectively. It was found that essential macro and micro nutrients were present in the feed in low concentration on the other side mercury was present in high concentration in the feed samples.

scholarly journals Ti/RuO2-IrO2-SnO2 Anode for Electrochemical Degradation of Pollutants in Pharmaceutical Wastewater: Optimization and Degradation Performances

2020 ◽  
Vol 13 (1) ◽  
pp. 126
Author(s):  
Guozhen Zhang ◽  
Xingxing Huang ◽  
Jinye Ma ◽  
Fuping Wu ◽  
Tianhong Zhou
Keyword(s):  
Removal Rate ◽  
Inorganic Compounds ◽  
Oxide Coating ◽  
X Ray Diffraction ◽  
Pharmaceutical Wastewater ◽  
High Concentration ◽  
Dimensionally Stable Anodes ◽  
X Ray ◽  
Initial Ph ◽  
Cod Removal Rate

Electrochemical oxidation technology is an effective technique to treat high-concentration wastewater, which can directly oxidize refractory pollutants into simple inorganic compounds such as H2O and CO2. In this work, two-dimensionally stable anodes, Ti/RuO2-IrO2-SnO2, have been developed in order to degrade organic pollutants from pharmaceutical wastewater. Characterization by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) showed that the oxide coating was successfully fabricated on the Ti plate surface. Electrocatalytic oxidation conditions of high concentration pharmaceutical wastewater was discussed and optimized, and the best results showed that the COD removal rate was 95.92% with the energy consumption was 58.09 kW·h/kgCOD under the electrode distance of 3 cm, current density of 8 mA/cm2, initial pH of 2, and air flow of 18 L/min.

scholarly journals Assessment and Imaging of Intracellular Magnesium in SaOS-2 Osteosarcoma Cells and Its Role in Proliferation

Nutrients ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 1376
Author(s):  
Concettina Cappadone ◽  
Emil Malucelli ◽  
Maddalena Zini ◽  
Giovanna Farruggia ◽  
Giovanna Picone ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cell Growth ◽  
Magnesium Deficiency ◽  
Acid Synthesis ◽  
Osteosarcoma Cell ◽  
Osteosarcoma Cells ◽  
High Concentration ◽  
Proliferating Cells ◽  
Intracellular Magnesium ◽  
In Cells

Magnesium is an essential nutrient involved in many important processes in living organisms, including protein synthesis, cellular energy production and storage, cell growth and nucleic acid synthesis. In this study, we analysed the effect of magnesium deficiency on the proliferation of SaOS-2 osteosarcoma cells. When quiescent magnesium-starved cells were induced to proliferate by serum addition, the magnesium content was 2–3 times lower in cells maintained in a medium without magnesium compared with cells growing in the presence of the ion. Magnesium depletion inhibited cell cycle progression and caused the inhibition of cell proliferation, which was associated with mTOR hypophosphorylation at Serine 2448. In order to map the intracellular magnesium distribution, an analytical approach using synchrotron-based X-ray techniques was applied. When cell growth was stimulated, magnesium was mainly localized near the plasma membrane in cells maintained in a medium without magnesium. In non-proliferating cells growing in the presence of the ion, high concentration areas inside the cell were observed. These results support the role of magnesium in the control of cell proliferation, suggesting that mTOR may represent an important target for the antiproliferative effect of magnesium. Selective control of magnesium availability could be a useful strategy for inhibiting osteosarcoma cell growth.

OBSERVATIONS ON AMYLOLYTIC BACTERIA: III. CULTURAL CONDITIONS INFLUENCING THE BREAKDOWN OF STARCH BY STENOTHERMOPHILIC BACTERIA BELONGING TO BACILLUS STEAROTHERMOPHILUS

1952 ◽  
Vol 30 (4) ◽  
pp. 360-370 ◽  
Author(s):  
Egon Stark ◽  
P. A. Tetrault
Keyword(s):  
Yeast Extract ◽  
Bacillus Stearothermophilus ◽  
Soluble Starch ◽  
The Other ◽  
Ph Changes ◽  
Proteose Peptone ◽  
Cultural Conditions ◽  
Initial Ph ◽  
Commercial Medium ◽  
Agar Media

Thirty-five cultures of Bacillus stearothermophilus hydrolyzed five starches under various cultural conditions. Hydrolysis occurred regardless of the type, brand, or batch of starch; regardless of the initial pH or of the subsequent pH changes of the medium. Starch in broth was better attacked than in agar media. Some cultures hydrolyzed 0.5%, but not 1% starch; others hydrolyzed easily 10% soluble starch. Length of incubation was important. Certain cultures never formed acid or sugar from starch. Dextrinization was a more reliable indication of starch hydrolysis than was the formation of acid or sugar. Soluble starch gave more consistent results in repeated experiments than did nonsoluble starches. The type of protein medium determines strongly the formation of amylase. Trypticase was the best commercial medium, yeast extract came second. The other 10 media yielded fewer amylolytic cultures. Yeast extract added to media enhanced amylase formation, except with trypticase. Tryptose, proteose-peptone, and neopeptone inhibited the growth of most cultures.

Degradation of chlorpyriphos in water by advanced oxidation processes

2010 ◽  
Vol 10 (1) ◽  
pp. 1-6 ◽  
Author(s):  
R. Murillo ◽  
J. Sarasa ◽  
M. Lanao ◽  
J. L. Ovelleiro
Keyword(s):  
Reaction Time ◽  
Light Source ◽  
Advanced Oxidation Processes ◽  
Advanced Oxidation ◽  
The Other ◽  
Molar Ratio ◽  
Optimum Conditions ◽  
Oxidation Processes ◽  
Other Hand ◽  
Initial Ph

The degradation of chlorpyriphos by different advanced oxidation processes such as photo-Fenton, TiO2, TiO2/H2O2, O3 and O3/H2O2 was investigated. The photo-Fenton and TiO2 processes were optimized using a solar chamber as light source. The optimum dosages of the photo-Fenton treatment were: [H2O2]=0.01 M; [Fe3 + ]=10 mg l−1; initial pH = 3.5. With these optimum conditions total degradation was observed after 15 minutes of reaction time. The application of sunlight was also efficient as total degradation was achieved after 60 minutes. The optimum dosage using only TiO2 as catalyst was 1,000 mg l−1, obtaining the maximum degradation at 20 minutes of reaction time. On the other hand, the addition of 0.02 M of H2O2 to a lower dosage of TiO2 (10 mg l−1) provides the same degradation. The ozonation treatment achieved complete degradation at 30 minutes of reaction time. On the other hand, it was observed that the degradation was faster by adding H2O2 (H2O2/O3 molar ratio = 0.5). In this case, total degradation was observed after 20 minutes.

scholarly journals STUDIES ON THE BACTERIOPHAGE OF D'HERELLE

1925 ◽  
Vol 42 (4) ◽  
pp. 483-497 ◽  
Author(s):  
Jacques J. Bronfenbrenner ◽  
Charles Korb
Keyword(s):  
Quantitative Evaluation ◽  
Bacterial Species ◽  
Relative Concentration ◽  
Serial Dilution ◽  
The Other ◽  
Resistant Bacteria ◽  
Dilution Method ◽  
High Concentration ◽  
Average Size ◽  
Broth Dilution

The experiments reported above confirm the fact that lytic principle is distributed in active solution in a state of indivisible units. This permits its quantitative evaluation by serial dilution, as well as by plating on agar. The latter method, however, often gives readings considerably lower than those obtained by the broth dilution method of titration. By varying the concentration of agar it has been possible to show that the discrepancy is due to adsorption of the lytic agent on agar. When the concentration of the latter is increased from 0.3 per cent to 2.5 per cent the number of plaques of lysis is reduced more than 100 times. At the same time the average size of the plaques also decreases approximately to one-tenth of the original. The size, as well as the number of plaques, has been found to depend also on the condition of the culture employed in titration. Thus, when the culture exposed to the action of lytic agent is composed of young susceptible bacteria, the greater the concentration of bacteria, the smaller the plaques. When the culture is composed partly of young and partly of old susceptible bacteria, both the size and the number of the plaques are diminished with the increase in the relative concentration of old bacteria. On the other hand, presence in the culture of resistant bacteria does not affect either the size or the number of the plaques so long as the relative concentration of susceptible bacteria in the culture is sufficient to allow formation of them. The plaques appearing in the presence of a high concentration of resistant variants in the culture are relatively indistinct owing to overgrowth. Under carefully controlled conditions the size of plaques is found to be determined by the character of the lytic filtrate. Thus in the case of lytic agents which act upon more than one bacterial species the size of the plaques remains constant, irrespective of the bacterial substratum used for the production of the active filtrate.

scholarly journals Phenotypic correlations among meat quality traits in broilers

2011 ◽  
Vol 41 (8) ◽  
pp. 1475-1481 ◽  
Author(s):  
Luana Bertollini de Jesus Silva ◽  
Leila de Genova Gaya ◽  
Ana Paula Madureira ◽  
Graziela Tarôco ◽  
José Bento Sterman Ferraz ◽  
...  
Keyword(s):  
Meat Quality ◽  
Protein Denaturation ◽  
The Other ◽  
Poultry Meat ◽  
Quality Traits ◽  
Ph Measurements ◽  
Water Losses ◽  
Phenotypic Correlations ◽  
Meat Quality Traits ◽  
Initial Ph

The goals of this research were to estimate the phenotypic correlations among various meat quality traits from a male broiler line and to describe the relation among these variables. Phenotypical correlations were determined among quality traits, isolating the effects of slaughter date, the age of the mother and sex. The evaluated traits were pH measurements taken at time 0 and at 6 and 24 hours after slaughtering, color parameters, water loss due to exudation, thawing and cooking of the meat, and shear force. Important associations (P<0.01) were found to be significant and, in most cases, weak or moderate, varying from -0.35 to 0.28. The initial pH of the meat was not associated (P>0.05) to the other traits of the meat, whereas the pH at 24 hours after slaughter was able of directly interfering with the attributes of the meat, since this trait was inversely related with lightness and water losses, which indicates an effect of pH fall along 24h after slaughtering on protein denaturation. This study demonstrates that the variables of poultry meat quality are related and that there is a phenotypical association between lightness and cooking losses and the other attributes of the meat. The pH at 24 hours after slaughtering, lightness and cooking losses could be efficient meat quality indicators in this broiler line.

scholarly journals Pre-fermentative treatment of a model wine with aim to serve as a functional food with decreased alcohol content

2017 ◽  
Vol 63 (01) ◽  
pp. 47-53
Author(s):  
Irina Mladenoska ◽  
Verica Petkova ◽  
Tatjana Kadifkova Panovska
Keyword(s):  
Enzyme Activity ◽  
Gluconic Acid ◽  
Functional Food ◽  
Ph Value ◽  
Enzymatic Reaction ◽  
Alginate Beads ◽  
High Concentration ◽  
Ph Optimum ◽  
Enzyme Preparations ◽  
Initial Ph

The effect of substrate concentration on the enzyme activity in the reaction of glucose conversion into gluconic acid was investigated by using three different enzyme preparations in media with two different glucose concentrations. The media were simulating the conditions in the must, thus named as minimal model must, and were composed form combination of several organic acids and glucose. Those media were having initial pH of 3.5 that is a very unfavorable for glucose oxidase activity having a pH optimum at the pH value of 5.5. Among the three preparations used, the bakery additive, Alphamalt Gloxy 5080, was the most active in the medium with glucose concentration of 10 g/L, showing conversion of more than 70% for the period of 24 h, while the same enzyme preparation in the medium with 100 g/L glucose converted only about 7% of glucose. The pH value of the medium at the beginning and at the end of the enzymatic reaction was a good indicator of the enzyme activity. It seems that for the conversion of glucose in higher concentration, enzymatic preparation in high concentration should also be used. The preliminary attempt of immobilization of two preparations of glucose oxidases in alginate beads was also performed and a successful immobilization procedure for utilization in food industry was preliminarily developed. Keywords: glucose oxidases, enzymatic pretreatment, glucose, gluconic acid, model wine, functional food

Development of breathable Janus superhydrophobic polyester fabrics using alkaline hydrolysis and blade coating

2018 ◽  
Vol 89 (6) ◽  
pp. 959-974 ◽  
Author(s):  
Seonyoung Youn ◽  
Chung Hee Park
Keyword(s):  
Mechanical Properties ◽  
Alkaline Hydrolysis ◽  
Structural Changes ◽  
Treatment Time ◽  
Volume Ratio ◽  
Alkaline Treatment ◽  
The Other ◽  
Solution Temperature ◽  
Optimal Conditions ◽  
Wetting Properties

Alkaline hydrolysis is a common finishing method that is used to give polyester (polyethylene terephthalate, PET) a more natural touch and improved luster via chemical or physical changes in the fibers. However, its potential as a tool for surface modification in the development of single-sided superhydrophobic materials has not been studied yet. In this research, Janus superhydrophobic PET fabrics with asymmetric wetting properties (one side of the PET surface was rendered superhydrophobic while the other side was simply hydrophobic) were fabricated in two steps. Fine roughness was first achieved on the surface of PET fabrics by alkaline hydrolysis. Subsequently, optimized foam-coating emulsions were applied on only one surface of the alkaline-hydrolyzed PET. Alkaline treatment time, solution temperature, and viscosity of the foam-coating emulsions were varied to find optimal conditions in terms of structural changes, mechanical properties, superhydrophobicity, and absorption ability. The specimen treated with an aqueous solution of 8% sodium hydroxide at 70℃ for 60 min and coated with the mixture of the fluoro-emulsion and thickener in the volume ratio of 40:2 was determined to be the optimal conditions for the Janus superhydrophobic property. This sample showed a contact angle of 162.8° and a shedding angle of 5.6° on one side, whereas it completely permitted the percolation of water drops on the other side within 109 s. The mechanical properties of the developed Janus PET under the optimal conditions did not decrease significantly; its weight and tensile strength were found to have decreased by 3.3% and 19.2%, respectively. Furthermore, the single-sided superhydrophobic specimen demonstrated higher moisture transmissibility than the double-sided coated PET under the same alkaline treatment conditions. The method developed herein eliminates the requirement for an additional process to deliver nanoscale surface roughness and has the potential to produce waterproof–breathable PET fabrics for outdoor clothing.

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