Browse Our Chemical Engineering Journals
Chemical engineering is an engineering branch that deals with the chemical production and manufacture of products that undergo chemical processes. This includes equipment design, creating systems and processes to refine raw material, as well as mixing, compounding, and processing chemicals to create products.
Chemistry and Chemical Engineering
Abstract
Garcinol, the main polyisoprenylated benzophenone present in Garcinia species. A simple, rapid, reliable high-performance thin-layer chromatography (HPTLC) technique has been developed for simultaneous detection and quantification of garcinol in three endemic Garcinia sp. of Assam, India. While G. mangostana and G. indica have garnered extensive recognition, these lesser-known species have not received proportionate level of scientific exploration, therefore has served as the subject of investigation. Chromatographic separation was achieved using pre-coated silica gel 60 F254 plates. The optimized mobile phase (Toluene-Ethyl acetate-Formic acid, 5:4:1V/V) at 276 nm produced well-defined and sharp peaks of garcinol, maintaining a constant R F value of 0.75. The regression equation demonstrated a linear relationship with a correlation coefficient of 0.9955. The method was validated in accordance with International Conference of Harmonization guidelines (ICH), encompassing assessments for precision, accuracy, repeatability and robustness, all of which yielded low percentage of relative standard deviation values, attesting to its excellent performance. The content of garcinol found in the extracts were in the range of 0.58–0.98% w/w. In secondary metabolite analysis, significant amount of phenols (26.06 ± 1.65–57.51 ± 2.62 gallic acid equivalent mg g−1), flavonoids (11.27 ± 1.06–21.09 ± 1.34 quercetin equivalent mg g−1) and ascorbic acid (3.56 ± 0.12–3.65 ± 0.11 mg/10 g) contents were detected in the extracts. Further, the extracts exhibited good anti-radical activity, which may be attributed to the presence of important secondary metabolites. Therefore, this research establishes the three endemic Garcinia sp. as promising source of garcinol. Additionally, the developed method can be applied for routine quality control analysis of herbal formulations containing garcinol.
Abstract
This study aims to predict drought periods affecting the Tokaj-Hegyalja wine region and the application of this in crop protection. The Tokaj-Hegyalja wine region is the only closed wine region in Hungary with a specific mesoclimate and a corresponding wine grape variety composition, in which climate change strongly threatens cultivation. The probability that a randomly selected day in the vegetation period will fall into a drought period in the future was estimated using the daily precipitation amount and daily maximum temperature data from the Hungarian Meteorological Service for the period 2002–2020. The Markov model, a relatively new mathematical method for the statistical investigation of weather phenomena, was used for this. Markov chains can, therefore, be a valuable tool for organizing integrated pest management. This can be used to plan irrigation, control fungal pathogens infecting the vines, and plan the success of a given vintage.
Abstract
In accordance with the International Coordinating Committee's recommendations, an acceptable UPLC-MS method is being developed for analyzing Relugolix stability under various stress scenarios. Stress conditions included exposure to 0.1 and 1 N acid, alkali, hydrolysis, peroxide, light, reduction, and heat. The mobile phase for this analysis was prepared by blending acetonitrile and a 0.1% orthophosphate solution in a 50:50 (v/v) ratio. A C18 Column with dimensions of 100 × 2.1 mm and a particle size of 1.7 µm was employed as the stationary phase. The wavelength at which detection was performed was 247 nm, and the flow rate was maintained stable at 0.5 mL min−1. Strong linearity was shown by this method across a concentration range of 1.25 μg mL−1 to 7.5 μg mL−1. The method's reliability was shown by ensuring all of the validation parameters fell within the acceptable range.
Furthermore, forced degradation studies were conducted using standard drugs. Different stress conditions led to the formation of degradation products, which were successfully separated from Relugolix using the C18 column in combination with an auto-purification mass spectrometer. Among the stress conditions, alkaline conditions showed a lower degradation rate. Interestingly, seven distinct types of degradation products were identified from the degradation studies under acid, alkali, hydrolysis, hydrogen peroxide, light, reduction, and thermal conditions. Remarkably, these seven degradation products have not been reported in previous literature, making this study the first to document their existence.
Abstract
The utilization of sea buckthorn pomace (SBP) is attracting growing attention since it is valuable industrial waste. This pomace can find usage as a functional ingredient of food because it contains bioactive, health-promoting components, but to our knowledge, few scientists have so far studied utilization of the antimicrobial activity of fruit pomace. The study aims are to broaden our knowledge of antioxidant and antimicrobial status of SBP by utilizing pomace as a functional apple juice ingredient and by monitoring the antioxidant capacity, the total polyphenol content and microbial changes that occur during the storage of juice samples. Our results of this study highlight that the importance of the utilization of SBP because the results reported here provide further evidence that SBP can contribute to increasing the content of valuable components in apple juice samples and inhibiting the growth of microorganisms during storage.
Abstract
This study deals with the development of HPLC assay method for the determination of guaifenesin (GUF), bromhexine (BRH), chlorpheniramine (CHP), and dextromethorphan (DEE) in bulk and Leekuf tablets. Column C18 Aligent eclipse was used to analyse GUF, BRH, CHP and DEE. The H3PO4 (0.01%) and methanol combined in 70:50 (vol/vol) parts was used as mobile phase. The HPLC assay method was validated in accordance with the ICH prerequisite and was capable of providing accurate (99.90% recovery for BRH, 99.40% recovery for CHP, 100.00% recovery for GUF and 99.50% for DEE) and precise (0.160–0.805% RSD range for GUF, BRH, CHP and DEE) quantitative results under slight variations in chromatographic circumstances in the range of quantities 25–150 μg mL−1 (GUF), 2–12 μg mL−1 (BRH), 0.5–3 μg mL−1 (CHP) and 2.5–15 μg mL−1 (DEE). These results concluded that HPLC assay method developed was beneficial for the evaluation of GUF, BRH, CHP and DEE simultaneously in commercial tablet dose. The degradants eluted are well resolved from the GUF, BRH, CHP, and DEE peaks, showing that the process is stability indicating.
Abstract
Objective
To establish a method for the high-performance liquid chromatography (HPLC) fingerprint and content determination of Wuwei Zhenju Tablets, and combine with chemical pattern recognition analysis to provide basis for its quality evalution.
Methods
Based on HPLC, taking the chromatographic peak of puerarin as the reference peak, the fingerprints of 10 batches of Wuwei Zhenju Tablets were established and the similarity evaluation was carried out to determine the common peaks. SPSS 26.0 and SIMCA 14.1 software were used to evaluate the overall quality of Zhenju Tablets by cluster analysis and principal component analysis. The contents of chlorogenic acid, puerarin, daidzin, isochlorogenic acid B, isochlorogenic acid A and aurantio-obtusin in the samples were determined by the same method.
Results
Twenty-six common peaks were identified in the fingerprints of 10 batches of Wuwei Zhenju Tablets, and the similarity evaluation was greater than 0.985. Ten chromatographic peaks were identified as neochlorogenic acid, chlorogenic acid, caffeic acid, puerarin, daidzin, isochlorogenic acid A, isochlorogenic acid B, isochlorogenic acid C, aurantio-obtusin and betaine. Combined with cluster analysis and principal component analysis, 10 batches of samples can be clustered into two categories, which can distinguish different Zhenju tablets. The model established in pattern recognition research can accurately identify Wuwei Zhenju tablets, and the prediction results are ideal. The six index components had a good linear relationship in their respective concentration ranges. The contents of chlorogenic acid, puerarin, daidzin, isochlorogenic acid B, isochlorogenic acid A and aurantio-obtusin in 10 batches of Wuwei Zhenju Tablets were 2.902–5.819, 3.693–49.680, 1.449–10.654, 2.768–7.724, 2.941–6.343 and 0.071–0.089 mg g−1, respectively.
Conclusion
The HPLC fingerprint and multi-component content determination method of Wuwei Zhenju Tablets were established for the first time. The method is simple, efficient and accurate, and can effectively provide experimental basis for the quality control and evaluation of the preparation.
Az erdőállományok talajvíz utánpótlódásra gyakorolt hatásának vizsgálata kecskemét-ménteleki mintaterületen
Investigation of the impact of forest stands on groundwater recharge in the Kecskemét-Méntelek study area
Az Alföldet, azon belül is különösen a Homokhátságot érintő talajvízszint süllyedés, súlyos ökológiai és gazdasági következményekkel is járó problémakör. A jelenség hátterében álló lehetséges okokkal kapcsolatban több évtizede zajlik kutatómunka, ugyanakkor ezek relatív súlyának meghatározása a mai napig tudományos vita tárgyát képezi.
Több szerző is kiemeli az erdőtelepítések talajvízszint csökkentő hatásának fontosságát. Ez a hatás két módon, a vegetáció vízfelvétele, illetve a csapadékból történő utánpótlódás csökkentése (intercepció, talajnedvesség felvétel) által jelentkezhet. Ezen mechanizmusok működését vizsgáltuk meg egy akác (Robinia pseudoacacia) és egy fekete fenyő (Pinus nigra) állomány esetében a Homokhátságon, Kecskemét-Ménteleken kialakított mintaterületünkön, 90, 150 és 200 cm-es mélységben, nagy időbeli felbontással mért talajnedvesség, illetve talajvíz adatokra alapozva.
Az adatok alapján feltételezhető, hogy a talajvízből nem történik közvetlen, vagy közvetett vízfelvétel, aminek oka vélhetően a gyökérzóna és a talajvíz közti igen jelentős horizontális távolság. A talajnedvesség esetében a sekélyebb rétegekben egyértelműen jelentkezik az erdőállományok szezonális szárító hatása. Ugyanakkor a mélyebb rétegek talajnedvesség adatai alapján kijelenthető, hogy a csapadékból történő talajvíz visszatöltődésre leginkább az akác állomány alatt van elméleti lehetőség. A látszólagos ellentmondás feltételezhetően a gyökérzet által kialakított makropórusok hatásával magyarázható. Ezt támasztja alá az akác és fekete fenyő állományok közti igen jelentős eltérés is.
Következtetésünk, hogy az erdőállományok lokálisan jelentősen eltérő hatást gyakorolhatnak a talajvízszintre. Ezért a lezajló folyamatok hátterét, általános jellegű megállapítások helyett, az adott hidrológiai rendszer több elemét vizsgáló monitoring adataira alapozva lehetséges csak felderíteni.
Abstract
The prevalence of diabetes is increasing day by day as per a report by the year 2045, 1 out of every 8th individuals may suffer from diabetes. This research article focuses on developing and validating Metformin and Dapagliflozin in combination by using high-pressure liquid Chromatography (RP-HPLC). The validation of the method was followed as per the guidelines provided by the International Conference on Harmonization (ICH) and United States Pharmacopeia (USP). Separation of both drugs takes place in less than 4 min. This separation takes place using Phosphate buffer (pH 6.8) and acetonitrile in a 45:55 (v/v) ratio at a 1.0 mL min−1 flow rate. Furthermore, studies on both drugs were conducted by using the bulk and pharmaceutical dosage forms (Tablets). The developed method was accurate as drug recoveries in both cases of Metformin, and Dapagliflozin ranged between (100.8, 99.6, 98.8%) to (100.8, 99.3, and 101.5%) respectively having a concentration range of solutions between 70, 100 and 130 μg mL−1 dilution. The recommended method for simultaneous quantification of Metformin and Dapagliflozin was established and validated and no excipient interactions were found.
Abstract
This study investigates sustainable methods for producing protein from soybean expeller via pH-shifting processes, aiming to reduce water usage in alkaline extraction by adjusting solid-to-liquid ratios per cycle and employing isoelectric precipitants like lactic acid and lactic acid bacteria (Lactiplantibacillus plantarum and Lactococcus Lactis) to enhance functional and antioxidant properties over a wide pH range. Results indicate that the most efficient approach involves three 1:10 (w/v) extraction cycles with lactic acid bacteria as precipitants, demonstrating high productivity and low specific water consumption. Protein content and recovery yield showed no significant differences compared to alternatives with higher water consumption or less eco-friendly precipitants. Despite lower solubility, protein products precipitated with lactic acid bacteria formed stable emulsions, exhibiting superior free radical scavenging activity.
Abstract
Microencapsulation of flaxseed oil (FO) has received lots of attention in the food and biopharmaceutical industries. To produce FO microcapsules, aqueous emulsions of FO with polymeric carbohydrates (maltodextrin (MD) with dextrose equivalent (DE) 19, gum Arabic (GA) and modified starch (MS)) were prepared by a rotor stator homogenization and subsequently, dehydration of emulsions were performed by spray drying (SD). The objective of this research was to study the effects of different combinations of polymeric carbohydrates with FO in emulsion to obtain maximum encapsulation efficiency (EE). A 3 factorials–3 levels Box–Behnken design was used for the optimization purpose. The maximum EE was achieved using 0.79 MD-GA ratio, 20.23% MS and 24.62% FO in emulsion. Microcapsules obtained by optimum condition had EE 77.68%, particle size (D 32) 120.0 ± 0.43 μm, moisture content1.6 ± 0.13%, wettability 192 ± 5.5 s, solubility 75.49 ± 1.3%, bulk density 0.31 ± 0.025 g mL−1, tapped density 0.36 ± 0.01 g mL−1, Carr's Index 13.88 ± 0.01% and Hausner Ratio 1.16 ± 0.01.
