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Abstract

Anisodus tanguticus (Maxim.) Pascher is an important Tibetan folk medicine and the source of tropane alkaloids (TAs) grown in Qinghai-Tibet Plateau. There are marked differences in quality of A. tanguticus from geographic areas. The aim of present research was to establish a method for the quantitative analysis of TAs coupled with chemometrics analysis to trace geographical origins. Qualitative analysis of TAs in A. tanguticus was carried out using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry and quantitative analysis of TAs in different plant organs from different geographical origin was achieved. Contents of TAs were subjected to the principal component analysis, and orthogonal partial least-squares discriminant analysis. The contents of the three marker compounds (anisodamine, anisodine and atropine) in the roots and acrial parts of A. tanguticus were positive correlated and varied significantly from different geographical origins. Principal component analysis, and orthogonal partial least-squares discriminant analysis results showed excellent discrimination between different geographical origin of A. tanguticus. This study could provide comprehensive evaluation and further utilization of A. tanguticus resources.

Open access

Abstract

Due to the wide applicability of separation techniques that rely on the property of differential migration in pharmaceutical formulations analysis, different analytical strategies have been proposed to resolve mixtures of multi-components pharmaceuticals. Three separation methods were developed and validated for the simultaneous determination of Paracetamol (PAR), Pseudoephedrine HCl (PSE) and Chlorpheniramine maleate (CHP). The first method is a thin-layer chromatographic (TLC) separation, followed by densitometric measurement. The separation was carried out on aluminium sheet of silica gel 60 F254 using ethanol:chloroform:ammonia (1:7:0.4, by volume) as the mobile phase. Determination of PAR, PSE and CHP was successfully applied over the concentration ranges of 3–25 µg/band, 0.5–10 µg/band and 0.1–6 µg/band, respectively. The second method is HPLC separation that was achieved on C18 column using the mobile phase acetonitrile:phosphate buffer pH 5 (10:90, v/v) at a flow rate 1 mL min−1. PAR, PSE and CHP were determined by HPLC in concentration ranges of 5–400 μg mL−1, 2–40 μg mL−1 and 0.5–16 μg mL−1, respectively. The third method is a capillary electrophoresis (CE) separation. The electrophoretic separation was achieved using 20 mM phosphate buffer (pH 6.5) at 20 kV. The linearity was reached over concentration ranges of 30–250 μg mL−1, 5–50 μg mL−1 and 0.8–20 μg mL−1 for PAR, PSE and CHP, respectively. The developed methods were validated with respect to linearity, precision, accuracy and system suitability. The proposed methods were successfully applied for bulk powder and dosage form analysis with RSD of precision <2%. Moreover, statistical comparison with the official methods confirms the methods' validity.

Open access

Abstract

The therapeutical applications of ornamental plants have been categorized to be of a great effectiveness in multiple industries from ancient times until present days. Pluchea dioscoridis is widely known Egyptian wooden plant that has been extensively applied for different medicinal purposes. In this study, LC-ESI-MS/MS analysis of the potent antimicrobial ethyl acetate and n-butanol extracts of P. dioscoridis leaves led to identification of 28 and 21 compounds, respectively. The identified compounds were categorized as phenolic acids, phenolic acids derivatives, organic acids, flavonoids (aglycones and glycosides), secoiridoids, coumarin derivatives, and gallotannins derivatives. Among them, caffeic acid 3-sulfate was the most predominate in the investigated extracts followed by ferulic acid and dicaffeoyl-quinic acid. Also, the antimicrobial potentiality of different extracts was evaluated against different pathogenic microbes including Enterobacter cloacae, Micrococcus leutus, Aeromonas hydrophila, Bacillus subtilis, Bacillus cereus, Bacillus lichneformis and Clostridium species. Furthermore, different concentrations of the most potent extract were assayed for antibacterial efficacy on growth curve kinetics against the susceptible bacteria along 4days incubation period. Our gathered data confirmed that, the antimicrobial activity against tested bacteria was different according to the solvent used in the extraction process. Mostly, all the extracts showed a wide spectrum antibacterial activity except the plant water extract which shows a mild activity against Clostridium sp. only. Based on the highest inhibition zone diameter, the ethyl acetate extract followed by butanol extract exhibited the highest inhibition zone with Micrococcus luteus and B. subtilis (20.0 and 18.5 mm) respectively. Determining the effect of ethyl acetate extract at different concentration (0, 0.66, 1.66, 3.33, 6.67, 13.34 and 20.01 mg mL−1) on M. luteus growth kinetics, the data assured that the antibacterial activity shows concentration dependent manner with the highest antibacterial activity at 20.01 mg mL−1 culture. The data also confirmed that, none of the selected concentration showed bactericidal activity in the prepared cultures, and with the prolonged incubation period the bacteria acquire resistance against the extract beginning from second or third day of incubation.

Open access

Abstract

In the case of fruit syrups, consumers prefer thicker, deep-coloured ones because they remind them of good old homemade ones. Physical properties – as viscosity, colour, refractive index, soluble solid content (SSC), and electrical impedance - of fruit syrups flavoured with raspberry or orange juice were determined. The change of the measured physical properties was determined in three different experiments: 1. evaluating the effect of sugar and sweetener content 2. evaluating the effect of fruit juice composition and 3. evaluating the effect of sugar content on syrups containing raspberry or orange juice only. Variations in fruit and sugar content had a definite effect on the physical properties of squashes. Viscosity, SSC value, refractive index, and impedance magnitude increased with increasing sugar content and decreased with replacement of sugar with sweeteners although colour characteristics were defined mostly by the colorant added to the squash. Changes in the fruit composition of syrups could influence viscosity, refractive index, and SSC values but the magnitude of impedance showed little changes for all samples. The characteristics of squashes containing only raspberry or orange juice and different sugar content did not follow any trends, which emphasized that additives had a significant effect on the physical properties.

Open access
Acta Chromatographica
Authors: Jelena Dzudovic, Milkica Crevar Sakac, Marko Antunovic, Aleksandra Repic, Slobodan Obradovic, Snezana Djordjevic, Jelena Savic, and Boris Dzudovic

Abstract

Oral anticoagulants are a group of drugs used for the prevention and treatment of venous thrombosis and venous thromboembolism. For the last ten years, direct oral anticoagulants (DOAC) have been available and are equally effective, but significantly safer than vitamin K antagonists. In the case of an overdose, their most important side effect is still bleeding. Due to their widespread use, as well as increased toxicological importance there is a need to develop an analytical method for the determination of DOAC in biological material.

The aim of this paper was to establish a method for the quantification of apixaban as one of the representatives of DOAC. The methodology of the study included the measurement of apixaban in the plasma of patients treated in the intensive care unit. Plasma apixaban concentrations were determined by LC-MS/MS technique using carbamazepine as an internal standard. Obtained validation parameters indicate that the introduced method is sensitive, reliable, precise and accurate. Using this method, apixaban can be quickly and easily detected and quantified in plasma in patients who are suspected of overdosing with this drug.

Open access

Abstract

A sweeping micellar electrokinetic chromatography (sweeping-MEKC) method was developed for the determination of 1,7-naphthalenediol, 2,3-naphthalenediol, 1,5-naphthalenediol and 2,7-naphthalenediol in cosmetics. Several parameters affecting sweeping-MEKC method were studied systematically and the separation conditions were optimized as 20 mM NaH2PO4–110 mM SDS and 40% (v/v) MeOH (pH 2.4), with −22 kV applied voltage and UV detection at 230 nm. The sample matrix is 60 mmol L−1 NaH2PO4 and sample introduction was performed at 3 psi for 6 s. Separation of the four naphthalenediols was completed in less than 17 min. Limit of detection (LOD) and limit of quantitation (LOQ) are 0.0045∼0.0094 μg mL−1 and 0.015∼0.031 μg mL−1. Linear relationship (r 2 > 0.999) is satisfactory at the range of 0.1–10 μg mL−1. The developed method has been successfully applied to the determination of the four naphthalenediols in real cosmetic samples, with recoveries in foundation, sun cream and lotion in the range of 92.3%∼106.8% and relative standard deviation (RSD) less than 4.15%. A HPLC method described in the National Standards of the People’s Republic of China was carried out for the comparison with the proposed method. The results showed that the proposed sweeping-MEKC method has the advantages of fast, low cost with comparative sensitivity.

Open access

Abstract

Napping is one of the rapid sensory profiling methods, which was established recently to meet the needs of sensory and consumer researchers. This approach provides a holistic evaluation of the tested sample through their positioning in a 2-dimensional space. The protocol of the analysis is somewhat different from the traditionally applied descriptive methods, like Quantitative Descriptive Analysis. In our review, we focus on the applicability of Napping in the field of fermented goods. The accompanying procedures are also investigated (typically Flash Profiling, CATA, and further methods), in order to understand how the combined datasets facilitate the understanding of the sensory characteristics of the products.

Open access
Progress in Agricultural Engineering Sciences
Authors: Anna Visy, Karina Ilona Hidas, Annamária Barkó, Lien Le Phuong Nguyen, László Friedrich, and Gábor Jónás

Abstract

Consuming enough protein is a very important part of a balanced and healthy diet. Complete proteins are those in which all essential amino acids are present. In meat products, like hams, many different reactions occur during ageing and storage. For example, the production of free amino acids or the production of biogenic amines is formed by decarboxylation. In this study, the presence of these amino acids and biogenic amines, as well as the quality properties of cured hams during curing and ageing, were investigated.

The meat samples were immersed into 100 g L−1 NaCl brine. The curing took 20 days, followed by smoking and ageing for 35 days (12 °C, 75% RH). The wet-cured ham samples were analysed for changes in NaCl concentration (at 3 parts: surface, core, bottom layer). Moreover, color, water activity, denaturation temperature and enthalpy (Differential Scanning Calorimetry), free amino acids (FAAs) and biogenic amines (BAs) were also evaluated.

Open access

Abstract

One of the most important components in spreads is the fat phase. The characteristics of the used fat determine most of the quality factors of the products such as viscosity, texture, colour, shelf life, etc. In these kinds of products, the commonly used fat is palm fat, however, in recent years it has had a bad press due to its negative environmental impact and health concerns. Therefore, the aim of our research was to develop a palm oil free hazelnut spread. We investigated the effect of replacing the fat in the fat phase with milk fat or coconut fat to the apparent viscosity, colour and texture properties of the product. According to our results the palm fat had the highest and coconut fat had the lowest viscosity. In texture analyses palm fat and milk fat showed no significant difference in hardness and in work of penetration. Coconut fat was significantly different in every texture attributes from the other samples. In the case of colour measurement all samples were significantly different. Despite the observed differences in some parameters the suitability of milk fat for hazelnut spread production should be further investigated (sensory analyses, shelf-life).

Open access

Abstract

In the current study, cakes were prepared with the addition of different levels of chia gel obtained by soaking 1 part of chia seeds in 9 parts of water by weight. Mix was allowed to stand for 30 min for gel formation and seeds were left in the gel and later incorporated into the batter. The addition of chia gel to cake batter to partially substitute the fat from the basic recipe (control) resulted both in improved quality characteristics at all levels of substitution and reduction of caloric value, at the expense of energy from fat, especially at higher reduction levels (40 and 60%). The fat replacement at 40 and 60% had a caloric value decrease by 48 kcal per 100 g compared to the control and respectively the energy at the expense of the fat was 37.9 and 25.7% (reduction by 71.3 and 48.3%). Sensory evaluation demonstrated good acceptability for all the products with slight prevail for the samples with 40% followed closer by those with 20% fat replacement. Hence, chia gel proved to be a good alternative for fat substitution in baking goods recipes while preserving the quality and sensory parameters aiming to produce healthier foods.

Open access