Journal of Chemistry
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Published By Hindawi Limited

2090-9071, 2090-9063

2022 ◽  
Vol 2022 ◽  
pp. 1-10
Author(s):  
Mengxuan Xiao ◽  
Sitong Liu ◽  
Huozhu Jin ◽  
Mingji Xiao ◽  
Huiqiang Wang ◽  
...  

The important quality of green tea is freshness, but high temperature, light, oxygen, and humidity during storage may reduce the freshness of green tea. Thus, this study investigated the freshness loss of green tea (FLGT) under an accelerated shelf-life testing (ASLT) by sensory evaluation and acceptability test. The FLGTs of the samples stored at 20°C, 30°C, and 40°C, were determined as 67 days, 55 days, and 45 days, respectively by the Q10 method. In addition, they were further determined as 67 days, 57 days, and 42 days, respectively, by the Weibull Hazard Analysis (WHA). The sensory evaluation and acceptability test confirmed the correctness of the above results by 2-alternative choice analysis and chemical analysis. The Q10 method was applied to predict the FLGTs stored at 4°C and −20°C which were 93 days and 150 days, which was further verified by 2-alternative choice analysis and chemical analysis. The results show that it is possible to predict the suitable drinking period of green tea during storage by the Q10 method.


2022 ◽  
Vol 2022 ◽  
pp. 1-10
Author(s):  
Eda E. Kılıç ◽  
İbrahim Halil Kılıç ◽  
Banu Koç

This study aims to determine the yoghurt production potential of lactic acid bacteria isolated from legumes seeds (lentils, beans, cowpea, and broad beans) and examine the effects of alginate capsules of selected starter cultures with high yoghurt production potential on the physicochemical properties, sensory properties of yoghurt, and bacterial viability during storage time at 4°C. The exopolysaccharide (EPS), proteolytic activity, and acidification properties of eight different isolates were determined, and sixteen different yoghurt combinations prepared. The samples showed similar physicochemical (pH, titratable acidity, dry matter, and whey separation), bacterial count, and sensory results in comparison with the commercial yoghurt used as a control sample. The acidity and pH of the yoghurt samples were significantly affected by the storage time. Total solids of yoghurt samples generally tend to decrease and syneresis of yoghurt samples also differed for each starter culture combination during the storage time. The total count of lactic acid bacteria during the storage time was higher than 107 CFU/g. The sensory analysis results of bacterial combinations are significantly different ( p < 0.05 ). Results indicated that isolated starter cultures have potential as commercial starters to improve the quality of yoghurt. Selected starter cultures with yoghurt production potential were encapsulated. Lactic acid bacteria with encapsulation efficiency of 86,3 ± 0,2 and 82,26 ± 0,79 were selected for yoghurt production. The physicochemical properties of the yoghurt with free and encapsulated starter culture were significantly different during the storage time. The reduction (∼0,5 log cfu/g) in the numbers of free and encapsulated starter cultures is over during the storage time ( p < 0.05 ). The acceptability of yoghurt containing encapsulated bacteria was lower than the yoghurt containing free bacteria by the panelists. Consequently, it was determined that alginate capsules increased bacterial viability, but the sensory properties of yoghurt were affected adversely. The LAB isolated form legumes can be introduced to the national microbial collection.


2022 ◽  
Vol 2022 ◽  
pp. 1-11
Author(s):  
G. Loganathan ◽  
M. Kannan

Biofuel production offers a non-fossil fuel that can be utilized in modern engines without any redesign. Regardless of receiving rising attention, many researchers have explored microalgae-based biofuel production and found biodiesel production is cost-effective compared to petroleum-centered conventional fuels. The primary reason is that the lipid accumulation of microalgae is possible. An efficient technique is proposed for optimized biodiesel manufacturing with microalgae through an IoT device with the hybrid particle swarm optimization (HPSO) algorithm for elapsing such drawbacks. First, the component of biodiesel is determined. Then, from the components, the temperature value is sensed through the IoT device. Based on the obtained temperature, the reaction parameters are optimized with HPSO to increase productivity and reduce cost. Finally, we observed performance and comparative analysis. The experimental results contrasted with the existent particle swarm optimization (PSO) and genetic algorithm (GA) concerning iteration’s temperature, concentration, production, and fitness. The present HPSO algorithm has differed from the existing PSO and GA concerning IoT sensed temperature and production function. Fitness value and instance concentration are the performance parameters. It varies based on the iteration values. Thus, the proposed optimized biodiesel production is advanced when weighed down with the top-notch methods.


2022 ◽  
Vol 2022 ◽  
pp. 1-15
Author(s):  
Temesgen Abeto Amibo ◽  
Surafel Mustefa Beyan ◽  
Tsegaye Markos Damite

The brown teff straw was utilized in this study to produce silica using the sol-gel technique. After pretreatment, the raw material of brown teff straw was characterized. The data were analyzed using the central composite design and response surface technique, and four independent parameters, namely, temperature, NaOH concentration, rotational speed, and extraction time, were evaluated for process optimization. Before extracting silica with an alkaline solution, the silica content in the ash was determined using an AAS spectrometer. The silica content of teff straw ash is around 92.89%. The ash was treated with NaOH solution in the concentrations range of 1 M to 3 M (0.5 M interval). The extraction time varied at intervals of 55, 70, 85, 100, and 115 minutes. Temperatures were changed using magnetic stirrer equipment in the range of 80°C to 100°C (5°C interval). At 350 rpm, 400 rpm, 450 rpm, 500 rpm, and 550 rpm, the rotating speed was adjusted. The best extraction conditions for amorphous silica were 1.50 M NaOH, 109.99 min, 94.98°C, and a rotating speed of 499.57 rpm, with a maximum yield of 85.85%. XRD and FTIR analyses were used to assess the physicochemical characteristics of the extracted silica. The aqueous solutions of methyl orange were used to test the adsorption efficiency of silica. The percent of removal efficiency for methyl orange was 90.48%.


2022 ◽  
Vol 2022 ◽  
pp. 1-50
Author(s):  
Mahrokh Marzi ◽  
Mojtaba Farjam ◽  
Zahra Kazeminejad ◽  
Abolfazl Shiroudi ◽  
Amin Kouhpayeh ◽  
...  

A pharmacophore system has been found as 1,2,3-triazole, a five-membered heterocycle ring with nitrogen heteroatoms. These heterocyclic compounds can be produced using azide-alkyne cycloaddition processes catalyzed by ruthenium or copper. The bioactive compounds demonstrated antitubercular, antibacterial, anti-inflammatory, anticancer, antioxidant, antiviral, and antidiabetic properties. This heterocycle molecule, in particular, with one or more 1,2,3-triazole cores has been found to have the most powerful antifungal effects. The goal of this review is to highlight recent developments in the synthesis and structure-activity relationship (SAR) investigation of this prospective fungicidal chemical. Also there have been explained drugs and mechanism of action of a triazole compound with antifungal activity. This review will be useful in a variety of fields, including medicinal chemistry, organic chemistry, mycology, and pharmacology.


2022 ◽  
Vol 2022 ◽  
pp. 1-15
Author(s):  
Zeeshan Saleem Mufti ◽  
Rukhshanda Anjum ◽  
Ayesha Abbas ◽  
Shahbaz Ali ◽  
Muhammad Afzal ◽  
...  

Topological indices are such numbers or set of numbers that describe topology of structures. Nearly 400 topological indices are calculated so far. The prognostication of physical, chemical, and biological attributes of organic compounds is an important and still unsolved problem of computational chemistry. Topological index is the tool to predict the physicochemical properties such as boiling point, melting point, density, viscosity, and polarity of organic compounds. In this study, some degree-based molecular descriptors of hydrocarbon structure are calculated.


2022 ◽  
Vol 2022 ◽  
pp. 1-8
Author(s):  
Ying Tang ◽  
Qiaojin Tang ◽  
Haiyan Luo ◽  
Xuehui Zhang ◽  
Qiuyu Chen ◽  
...  

Prenatal diagnosis is an important means of early diagnosis of genetic diseases, which can effectively reduce the risk of birth defects. Free fetal cells, as a carrier of intact fetal genetic material, provide hope for the development of high-sensitivity and high-accuracy prenatal diagnosis technology. However, the number of fetal cells is small and it is difficult to apply clinically. In recent years, noninvasive prenatal diagnosis (NIPD) technology for fetal genetic material in maternal peripheral blood has developed rapidly, which makes it possible to diagnose genetic diseases by fetal cells in maternal peripheral blood. This article reviewed the current status of fetal cell separation and enrichment technology and its application in noninvasive prenatal diagnosis technology.


2022 ◽  
Vol 2022 ◽  
pp. 1-8
Author(s):  
Qing-Qing Cao ◽  
Yan-Qing Fu ◽  
Cheng-Bin Zhang ◽  
Yan Zhu ◽  
Jun-Feng Yin ◽  
...  

Brewing water plays a crucial role in flavor and potential healthy functions of tea infusion. In this study, seven water samples with different physicochemical properties were selected to brew green tea. Results showed that the brewing water with higher minerals level and pH value would reduce the yield of catechins in tea infusion, which in turn caused the decrease of antioxidant activity to a large extent. Besides, it was found that EGCG, as a major contributor to the antioxidant activity of green tea infusion, was influenced differently by different metal ions, among which Ca2+/Mg2+ could enhance the antioxidant activity of EGCG solutions with different concentration through synergistic effect, particularly Ca2+, and the effect was more markable at a higher EGCG concentration. These results offered theoretical direction to the selection of tea brewing water for consumers and gave a new sight to the effects of metal ions on the antioxidant capacity of EGCG.


2022 ◽  
Vol 2022 ◽  
pp. 1-7
Author(s):  
Bac Nguyen Quang ◽  
Duc Ta Hong

Oyster shells are considered as a byproduct or solid waste in mariculture or related food processing areas that face a major disposal problem at the landfill in coastal regions for sustainable development. Oyster shell is composed mostly of CaCO3, and it is also considered as a secondary source of calcium for various applications. In this paper, we extracted the calcium carbonate from oyster shell and used it as the source of calcium for the preparation of feed-grade monocalcium phosphate (MCP). The investigation shows that the heavy metal contents in oyster shells as well as in the synthesized MCP are extremely low, and the synthesized product meets the requirements for the European Union (EU) maximum limits applied for feed additives. The XRD, TG, and IR data analyses confirmed that the synthesized product is monocalcium phosphate.


2021 ◽  
Vol 2021 ◽  
pp. 1-21
Author(s):  
Maisa M.A. Mansour ◽  
Yassin E. Zidan ◽  
Abou El Fettouh A Abd El Hakim ◽  
Mohamed Mahmoud Allam ◽  
Hayssam M. Ali ◽  
...  

Ancient stamps are suffering from the destructive effects of different kinds of inks that were prepared from different ingredients. Two Egyptian historical postage stamps printed in blue and red printing inks were evaluated and examined for their composition using a light microscope, SEM-EDS, FTIR, and Raman spectroscopic analyses. Mechanical, chemical, and deacidification treatments were done for the two stamps. Model stamps were made from the cotton pulp in the book house to simulate historical stamp paper with an average thickness of 11 microns. The unprinted and printed paper samples with printing inks that aged and unaged were treated with 0.7% Klucel G, 0.2% TiO2 NP, or a mixture of 0.7% Klucel G + 0.2% TiO2 NP, and the color change was measured and compared with the blank samples. The two stamps are suffering from high pH, where the margin color of the stamps changed to yellow-brown with weakness of the stamp paper. By SEM examination, stamps have suffered from fibers’ weakness and dryness resulting from the self-oxidation reactions. EDS elemental composition of the red stamp showed the presence of C, O, Na, Al, Si, Mg, S, Ca, Ba, and Fe, while in the blue stamp, it was C, O, Na, Al, Si, P, S, Cl, and Ca. Raman spectrometer wavelengths turn out that the blueprinting ink of the stamp was characterized with spectra of ultramarine blue (lazurite), while hematite was characterized by the red stamp. FTIR analysis for the printing inks identified that gum Arabic sample and linseed oil were the binding and color medium, respectively. From the model trials, it was observed that the treatment of a mixture of Klucel G and TiO2 NP had the best properties for the consolidation of stamps. The two historical stamps were documented through different spectroscopic analyses, and from the restoration trials, it was observed that the mixture of 7% Klucel G + 0.2% TiO2 NP appeared to be a new and effective method for recovering the historical postage stamps.


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