scholarly journals The Impact of Mineral Salts and Milk of Lime on Physicochemical Parameters and Swelling :( Case of Clays of Tlemcen Algeria)

2012 ◽  
Vol 2 (5) ◽  
pp. 25-30 ◽  
Author(s):  
Zeyneb Belabbaci ◽  
Sidi Mohamed Aissa Mamoune ◽  
Abdelmalek Bekkouche
Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3640
Author(s):  
Tomasz Tarko ◽  
Magdalena Januszek ◽  
Aneta Pater ◽  
Paweł Sroka ◽  
Aleksandra Duda-Chodak

Providing yeast with the right amount of mineral salts before fermentation can contribute to improving the entire technological process, resulting in a better-quality final product. The aim of this study was to assess the impact of apple must supplementation with mineral salts ((NH4)2SO4, MgSO4, (NH4)3PO4)) on enological parameters, antioxidant activity, total polyphenol content, and the profile of volatile cider compounds fermented with various yeast strains. Rubin cultivar must was inoculated with wine, cider, and distillery or wild yeast strains. Various mineral salts and their mixtures were introduced into the must in doses from 0.167 g/L to 0.5 g/L. The control sample consisted of ciders with no added mineral salts. The basic enological parameters, antioxidant properties, total polyphenol content, and their profile, as well as the composition of volatile compounds, were assessed in ciders. Must supplementation with magnesium salts significantly influenced the use of the analyzed element by yeast cells and was dependent on the yeast strain. In supplemented samples, a decrease in alcohol concentration and total acidity, as well as an increase in the content of extract and total polyphenols, was observed compared to the controls. The addition of ammonium salts caused a decrease in the amount of higher alcohols and magnesium salts, as well as a decrease in the concentration of some esters in ciders.


2020 ◽  
Author(s):  
Eirik A Moreb ◽  
Zhixia Ye ◽  
John P Efromson ◽  
Jennifer N Hennigan ◽  
Romel Menacho-Melgar ◽  
...  

A key challenge in synthetic biology is the successful utilization of characterized parts, such as promoters, in different biological contexts. We report the robustness testing of a small library of E. coli PhoB regulated promoters that enable heterologous protein production in two-stage cultures. Expression levels were measured both in a rich Autoinduction Broth as well as a minimal mineral salts media. Media dependent differences were promoter dependent. 4 out of 16 promoters tested were identified to have tightly controlled expression which was also robust to media formulation. Improved promoter robustness led to more predictable scale up and consistent expression in instrumented bioreactors. This subset of PhoB activated promoters, useful for two-stage autoinduction, highlight the impact of the environment on the performance of biological parts, and the importance of robustness testing in synthetic biology.


2021 ◽  
Author(s):  
M. M. Majedul Islam ◽  
Md. Atikul Islam

Abstract Faecal contamination of surface water sources is an important water quality issue worldwide. Although quite a few studies exist on surface water faecal contamination and variability of indicator bacteria, most of the studies have been based on larger river basins and in temperate region. The variability is relatively unknown in local scale and in tropical developing countries. In this study we assess how anthropogenic and environmental factors affect faecal contamination and physicochemical parameters in Rupsha and Bhairab rivers around Khulna city, Bangladesh. Water samples were collected from six locations of the rivers during a wet and dry period in 2018 to measure Escherichia coli (E. coli) concentrations. Water physicochemical parameters—temperature, turbidity, pH, dissolved oxygen, biochemical oxygen demand and chemical oxygen demand were also measured. Higher concentrations of E. coli were found in the sampling sites located near the densely populated urban area compared to the downstream site, which receives fewer amounts of discharges from sewer drains. All the E. coli samples violated bathing water quality standards. E. coli concentrations were found to be correlated positively with precipitation and turbidity. A linear regression model was applied, that explains large part of the variation in E. coli concentration (R2 = 0.42). Water quality index assessment was also ranked the water quality as ‘poor’ category; indicate that the water is unsuitable for uses in domestic and recreational purposes and high health risks involved with the water use. The study findings highlight the problem of untreated sewage discharge into the rivers. Implementation of sewage treatment plant with adequate capacity is highly recommended.


Author(s):  
J. C. Fopoussi Tuebue ◽  
I. N. Tchinda

The present paper aims to highlight the physicochemical evolution of solutions from soaking and beans cooking processes. For that purpose, solutions from soaking were produced by putting in contact 2kg of sorted and quickly washed beans seed with 8kg of water with known physicochemical characteristics. Concerning the solutions from cooked beans, they were produced by putting on fire the pot containing the water mixture from soaking and bean seeds. The beans were a variety of Phaseolus vulgaris L.,known as “Meringue”. The cooking process was done without salts. The samples of solutions were collected as follows: 30 and 60 minutes respectively after the start of the soaking, 30, 60, and 90 minutes after the beginning of the cooking process of the beans soaked for 60 minutes. After each sampling, the cooking solution was brought back to the gauge line using the water prepared for the cooking process. Solutions obtained from beans soaking and cooking gradually enriched in mineral salts, particularly major macro-elements (N and K), minor macro-elements (Ca, S, Mg) and oligo-elements compared to the situation noticed in the water used for the cooking process. Concerning the third main macro-element, notably the phosphorous, it is present in low amounts. The pH and the electric conductivity (EC) of the solutions increase with the duration of soaking and cooking processes. The amounts start their weak increasing thirty minutes after the beginning of the soaking, and continue their shy increasing up to the end of the sixtieth minute of the soaking. With the opening of the cooking process, the increase becomes abrupt. The correlation between all the parameters are globally positive. But the study of the clouds of dots reveals the impact of the temperature as the major responsible for the behavior of some of those elements despite the positive correlations established. The Pearson index in the correlations including sodium is the lowest.


Author(s):  
W. P. Wanjala ◽  
L. Odokuma ◽  
I. Etela ◽  
R. Ramkat

The study is a post project implementation Environmental Monitoring (EM) of impacts of anthropological activities on levels of soil physicochemical parameters. The study evaluates levels of physicochemical parameters in soils of 9 locations in Port Harcourt and its environs in Rivers State, Nigeria, grouped into 3 categories; urbanized, industrialized and agricultural. Composite soil samples were collected between April to October 2018. Concentration levels of Benzene, Toluene, Ethyl-benzene, and Xylene (BTEX), Total Petroleum Hydrocarbon (TPH), Percent Total Organic Carbon (% TOC), Lead (Pb), Iron (Fe), Copper (Cu), Cadmium (Cd), Zinc (Zn), Calcium (Ca), Nickel (Ni), Sodium (Na), Potassium (K), Chromium (Cr), Magnesium (Mg), Manganese (Mn), and Sulphur (S) in soil was measured using standard analytical procedures. The study evaluates the impact magnitude (IM) of the obtained test values against control values. In industrial area, BTEX recorded the highest Impact Magnitude (IM) of 100% while TOC and TPH recorded 100.00% and 88.89% respectfully, and were classified as severely impacted (S). In the agricultural areas, TOC and Ni recorded IM of 88.89% while BTEX had an IM of 77.78% which were highest and were classified as severe impact (S). In urbanized areas, Ni and (Phosphate) PO43- recorded the highest IM of 88.89% and were classified as severe (S). The study establishes that urbanization, industrialization and agricultural activities do affect the level of physicochemical parameters in the study areas. Activities in industrial areas negatively impact on levels of BTEX, % TOC and TPH in soils. Activities in agricultural areas negatively impacted on levels of BTEX, NO3-, NO2- and SO42- in soils, and activities in urban areas negatively impact on levels of Ni, PO43-, Zn, Mn, TPH, % TOC and Ca in soils of the study areas. These findings form a reliable baseline data for future researchers in EM in the study areas. The study recommends EM of soil physicochemical parameters in the study area in order to ensure a healthy soil for food production in order for realization of Sustainable Development Goals (SDGs); Good Health and well-being, and sustainable cities and communities.


Author(s):  
Vibha Shukla ◽  
Suresh Chandra Phulara

Recent years have seen a remarkable increase in the non-natural production of terpenoids from microbial route. This is due to the advancements in synthetic biology tools and techniques, which have overcome the challenges associated with the non-native production of terpenoids from microbial hosts. Although, microbes in their native form have ability to grow in wide range of physicochemical parameters such as, pH, temperature, agitation, aeration etc; however, after genetic modifications, culture conditions need to be optimized in order to achieve improved titers of desired terpenoids from engineered microbes. The physicochemical parameters together with medium supplements, such as, inducer, carbon and nitrogen source, and cofactor supply not only play an important role in high-yield production of target terpenoids from engineered host, but also reduce the accumulation of undesired metabolites in fermentation medium, thus facilitate product recovery. Further, for the economic production of terpenoids, the biomass derived sugars can be utilized together with the optimized culture conditions. In the present mini-review, we have highlighted the impact of culture conditions modulation on the high-yield and high-specificity production of terpenoids from engineered microbes. Lastly, utilization of economic feedstock has also been discussed for the cost-effective and sustainable production of terpenoids.


Foods ◽  
2019 ◽  
Vol 8 (7) ◽  
pp. 244 ◽  
Author(s):  
Malgorzata Nowacka ◽  
Silvia Tappi ◽  
Artur Wiktor ◽  
Katarzyna Rybak ◽  
Agnieszka Miszczykowska ◽  
...  

Beetroot is a root vegetable rich in different bioactive components, such as vitamins, minerals, phenolics, carotenoids, nitrate, ascorbic acids, and betalains, that can have a positive effect on human health. The aim of this work was to study the influence of the pulsed electric field (PEF) at different electric field strengths (4.38 and 6.25 kV/cm), pulse number 10–30, and energy input 0–12.5 kJ/kg as a pretreatment method on the extraction of betalains from beetroot. The obtained results showed that the application of PEF pre-treatment significantly (p < 0.05) influenced the efficiency of extraction of bioactive compounds from beetroot. The highest increase in the content of betalain compounds in the red beet’s extract (betanin by 329%, vulgaxanthin by 244%, compared to the control sample), was noted for 20 pulses of electric field at 4.38 kV/cm of strength. Treatment of the plant material with a PEF also resulted in an increase in the electrical conductivity compared to the non-treated sample due to the increase in cell membrane permeability, which was associated with leakage of substances able to conduct electricity, including mineral salts, into the intercellular space.


2018 ◽  
Vol 276 ◽  
pp. 204-209
Author(s):  
Marcin Kaczmarczyk

Renovation plasters need to be characterized by high porosity, appropriate pore size distribution and the ability to transport and accumulate mineral salts. In addition, they must perform functions of a regular plaster. One of the main features that every plaster should have is the resistance to shrinkage cracks. For salt-absorbing plasters, the need to use multiple layers necessitates an in-depth research of this phenomenon. The shrinkage crack formation is determined by the bending strength of mortars. This feature can be adjusted with the addition of different types of fibers. This paper presents a study on the change in bending and compressive strength of renovation plasters with the addition of 6 mm fibers. 0.05, 0.10, 0.15, 0.20% of polyethylene fibers and 0.10, 0.20, 0.30, 0.40% of glass and basalt fibers by mass ratio to dry mix were used. The results were referenced to mortars without fibers. Significant changes in mechanical properties were observed. Compression and bending strength increases with the fiber addition, reaching maximum values at 0.15% for PE and 0.20% for glass and basalt fibers. The best results were obtained for the latter ones.


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