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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
The relevance of the subject under study is conditioned by numerous technological problems of providing livestock enterprises of the Republic of Kazakhstan with quality equipment for animal feeding and the associated need to develop and implement dosers for the preparation of compound feed mixture. This study introduces an innovative approach through the development and analysis of a novel dosing auger with an active return channel, which distinguishes itself from existing models by enhancing the precision and efficiency of feed preparation processes. The purpose of this study was to investigate the key parameters of the dosing auger with an active return channel for its further use in agricultural enterprises for preparation of compound feed. The findings of this study emphasise the significance of compliance of current trends in the improvement of prepared feed with the established zootechnical requirements from the standpoint of optimising the technological equipment used in this process. The key aspects of feed dosing sequence when using volumetric and mass dosing methods were considered. The main advantages of auger-in-auger dosers that distinguish them from all other types of dosers were described.
Abstract
Dillenia indica is one of the important medicinal plants and is extremely popular in many systems of medicine including ayurvedic, homeopathic, and siddha. Traditionally, different parts of this plant have been used to treat cancer, wound healing, diabetes, diarrhea, bone fractures, abdominal pains, cuts and burns. In the present study, a simple, precise, accurate and validated high performance thin layer chromatographic (HPTLC) method was developed for simultaneous estimation of three pharmaceutically active compounds i.e., betulinic acid (BE), β-sitosterol (BT) and lupeol (LP) in fruits, leaves, root bark and stem bark of D. indica. Standards and plant samples were applied on TLC aluminum plate precoated with 0.2 mm layer of silica gel 60F254. The plate was run in a twin glass chamber comprising toluene:methanol:chloroform (8:1:1, v/v/v) as a mobile phase which resulted in better separation of compounds. The plates were immersed in anisaldehyde-sulfuric reagent and then heated at 105 °C for 5 min in CAMAG TLC plate heater for appearance of bands. Densitometric scanning was performed at λmax = 525 nm using tungsten light source in CAMAG TLC Scanner4 armed with WinCATS software. R F values of BE, BT and LP standards and those of plant samples were found to be 0.38 ± 0.01, 0.54 ± 0.01 and 0.65 ± 0.02 respectively. The method was further validated by following the International Conference of Harmonization (ICH) guidelines. For BE, BT and LP, the linear regression data for the calibration plots revealed a satisfactory linear association with correlation coefficients (r 2) = 0.9736, 0.9989 and 0.9957, respectively. Linear ranges for BE, BT and LP were 2,000–6,000 ng/band, 200–1,000 ng/band, and 200–600 ng/band respectively. Accuracy of the method was assessed by recovery study conducted at three different levels with the average recovery of 99.19, 99.69 and 100.95% for BE, BT and LP, respectively. The results exhibited the highest content of BE (0.148 ± 0.01%), BT (0.031 ± 0.01%) and LP (0.047 ± 0.01%) in stem bark. The developed method will be useful for routine and quality control analysis of fruits, leaves, root bark and stem bark of D. indica species.
Abstract
Artificial sweeteners are low-calorie substances used as food additives with aim to impart a sweet taste to beverages without adding significant calories. Due to the regulatory compliance regarding the type and the amount of artificial sweetener, and due to the large consumption of beverages and the effects of artificial sweeteners on human health, their identification and quantification is of a great importance. In this research simultaneous determination of acesulfame K (ACE-K), sodium saccharin (Na-SAC) and aspartame (ASP) as the most commonly used sweeteners in beverages was performed with a reversed – phase high performance liquid chromatography (RP – HPLC) with diode array detection (DAD). The best separation of the analytes was achieved on a Poroshell 120 EC-C18 (3.0 × 50 mm, 2.7 µm) column and isocratic elution with a mobile phase consisted of acetonitrile and diluted phosphoric acid (pH = 3.8) with 7/93 volume ratio (V/V), and flow rate of 1 mL min−1. The chromatographic process was followed at 195, 220 and 230 nm, under constant column temperature (25 °C). Under these chromatographic conditions, the total time of analysis was less than 5 min. The developed method was validated for linearity, precision, accuracy, limit of detection (LOD) and limit of quantification (LOQ). The LOD under established chromatographic conditions was 0.03, 0.07 and 0.17 mg L−1 for Na-SAC, ACE-K and ASP, respectively. The amount of artificial sweeteners in analyzed samples ranged from 30.32 to 148.37 mg L−1 for ACE-K, from 16.10 to 93.05 for Na-SAC, and from 6.06 to 512.72 for ASP. The validated method was successfully applied for determination of analytes in different commercially available beverages.
Abstract
People are consuming increasing amounts of poultry eggs and their products, and their safety is always a public concern. However, the complex composition of poultry eggs and their products, particularly the proteins and lipids, can easily cause matrix effects, requiring the use of sorbents to remove these components to avoid affecting the detection results. Zeolitic imidazolate framework-8 (ZIF-8) is a MOF material with high specific surface area, high porosity, and high stability, making it widely used as a sorbent in pesticide residue detection. In this study, we evaluated the performance of ZIF-8 compared to classic solid phase extraction (SPE) and Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) in the pretreatment step. The results showed that ZIF-8 could better reduce the matrix effect in poultry eggs and their products. After optimizing the extraction solvents, chromatographic and mass spectrometric conditions, and pretreatment processes, we established a method using ZIF-8 as a sorbent combined with high performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS) for the detection of 80 pesticide residues in seven different types of poultry eggs and their products, yielding satisfactory results. All the target analytes showed good linearity, both with values of r 2 > 0.996. The average recovery and coefficients of variation (CVs), expressed as relative standard deviations, ranges from 72.5% to 113.2% (chicken egg) (CV: 0.1%–12.9%), 72.2%–114.2% (salted duck egg) (CV: 0.1%–9.8%), 70.3%–105.6% (goose egg) (CV: 0.1%–12.0%), 70.9–120.4% (marinated egg) (RSD: 0.1%–14.8%), 70.7%–108.5% (duck egg) (CV: 0.1%–12.3%), 71.1%–105.0% (quail egg) (CV: 0.2%–5.6%), 70.7%–111.5% (century egg) (CV: 0.1%–13.4%). The values of limit of detection (LOD) and limit of quantification (LOQ) were, respectively, ranging from 0.15 to 0.85 μg kg−1 and 0.34–2.6 μg kg−1. When this method was applied to the detection of real samples, one chicken egg sample was found to contain 0.013 mg kg−1 of fipronil, and one marinated egg sample was found to contain 0.0087 mg kg−1 of thiamethoxam, indicating the necessity of stringent safety monitoring for poultry eggs and their products.
Abstract
Formaldehyde plays a significant role in the global economy due to its unique chemical properties and widespread use in both the medical field and various industrial sectors. However, formaldehyde (HCHO) is classified as a persistent organic pollutant and is known to be harmful. Exposure to formaldehyde, both direct and prolonged, can cause severe health issues and potentially lead to death. It is recognized as a human carcinogen by numerous organizations and can negatively impact the endocrine system, as well as having mutagenic or teratogenic effects. Formaldehyde has been detected in various matrices at levels exceeding those permitted by international health regulatory bodies. Chromatography, particularly high-performance liquid chromatography (HPLC) coupled with detection methods, is an analytical technique frequently used to determine volatile organic molecules, including formaldehyde. This investigation aimed to develop and validate an assay method to identify and quantify formaldehyde in cosmetic products using HPLC-PDA. The chosen isocratic system consisted of a ZORBAX RX-C8 column (250 mm × 4.6 mm; 5 μm) and a mobile phase mixture of acetonitrile and water in a 55:45 (v/v) ratio, with a flow rate of 1.5 mL min−1. Formaldehyde was detected at 353 nm after derivatization with a 0.1N 2,4-dinitrophenylhydrazine solution, with a retention time of approximately 5.0 min and a total run time of 7.0 min for formaldehyde. The method was validated according to ICH Q2 (R1) guidelines. The validation parameters demonstrated high selectivity, precision (RSD <2%), accuracy (mean recovery of 101.3%), linearity (r > 0.995 in the 1,000–2,400 ppm range), and a limit of quantification (LOQ) of 0.1 ppm. The validated analytical method was applied to 35 cosmetic products. None of these products were labeled as containing formaldehyde, although 6 imported products were labeled as containing formaldehyde-releasing preservatives. The results indicated that 88.6% of the samples tested positive for formaldehyde, with free formaldehyde levels ranging from 20 to 981 ppm. All samples contained formaldehyde levels below the 2000 ppm threshold.
Abstract
Currently, there are no reported green “high-performance thin-layer chromatography (HPTLC)” methods for domperidone (DOM) and cinnarizine (CNZ) simultaneous detection. The objective of the present study was to design and verify a reverse-phase HPTLC method for the concurrent analysis of CNZ and DOM in commercial tablets that is fast, sensitive, and greener. As a green mobile phase, acetone and water in an 80:20 (v/v) binary ratio were used to simultaneously determine CNZ and DOM. The stationary phase was reverse-phase silica gel 60F254S plates. Concurrent measurements of CNZ and DOM were performed at 230 nm. Four different tools were used to assess the greenness of the current method: AGREE, AES, ChlorTox, and NEMI. For both medications, the current approach was linear in the 25–1,000 ng/band range. The accuracy, precision, robustness, sensitivity, and environmental friendliness of the suggested technique for the CNZ and DOM simultaneous detection were verified. The new method's profile was noticeably greener, as seen by the results of every greenness tool, including NEMI, AES (89), ChlorTox (1.08 g), and AGREE (0.83). Utilizing the current approach, the amount of CNZ and DOM in pharmaceutical tablets was found to be 99.53 and 98.87%, respectively. These findings validate the suitability of the existing method for measuring CNZ and DOM simultaneously in commercial tablets. The results of the proposed study indicated that measuring CNZ and DOM in commercial products could be done consistently with the current methodology.
Abstract
A fast, accurate, sturdy, and sensitive UPLC-MS/MS method was developed to measure the levels of ADB-BUTINACA in rat plasma for a pharmacokinetic study. The ADB-BUTINACA and midazolam (internal standard) were separated on a UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 μm) using a gradient elution of acetonitrile and water (0.1% formic acid) as the mobile phase. ADB-BUTINACA and midazolam were detected in multiple reaction monitoring (MRM) mode for quantitative analysis, the mass detection was performed on a positive electrospray ionization (ESI) source. The calibration curve displayed excellent linearity from 1 to 1,000 ng mL−1, with a lower limit of quantification of 1.0 ng mL−1 and a limit of detection of 0.3 ng mL−1. The precision for both inter-day and intra-day assays was below 14%, while accuracy ranged from 92% to 111%. The method also showed an average recovery between 87% and 90%, with a matrix effect ranging from 104% to 111%. The data was acceptable according to the guidelines of the US Food and Drug Administration (FDA). This newly validated quantitative method successfully supported the pharmacokinetic study of ADB-BUTINACA.
Abstract
In the confectionery industry large quantities of palm fat in the fillings of chocolate products are used. Based on today's nutritional science results, it is desirable to replace palm oil with healthier fats. Oleogels can provide a kind of solution for this replacement. In our work the rheological, textural and thermal properties of oleogels containing high oleic sunflower oil, beeswax and monoglycerides were determined. In the samples we examined, the gelator concentrations were: 20% beeswax, 15% beeswax and 5% monoglyceride, 10% beeswax and 10% monoglyceride, 5% beeswax and 15% monoglyceride, and 20% monoglyceride. Based on our results, the oleogel containing 15% beeswax and 5% monoglyceride seems an eutectic crystal of beeswaxes and monoglyceride. It has relative high hardness, high storage modulus and high viscosity therefore it can replace the Chocofill filling fat, which contains mainly palm fat, used in large quantities in sweets.
Abstract
The use of edible coatings (ECs) containing essential oils (EOs), such as that derived from the Thymus vulgaris plant (EO-Tv), offers a natural option for preserving and increasing the shelf life of fruit and vegetable products. However, considering their physicochemical properties, the incorporation of EOs into nanocapsules (NCs) represents an alternative to reduce their volatility and oxidation. In this way, quantitative determination of the EOs incorporated into NCs is necessary for simultaneous monitoring of their main components during the nanoencapsulation process, as well as for the future precise and accurate dosage of EO components in fruit and vegetable products. In this study, ECs were formed from NCs loaded with EO-Tv and sodium alginate (AL). The EO-Tv was characterized through GC-MS and GC-FID analysis, and it was found that the major component of EO-Tv was thymol, with an abundance of 30.91%. Subsequently, an analytical method based on HS-SPME-GC-FID was developed and validated for quantification of the EO-Tv encapsulated in NCs and incorporated into the EC. The method was found to be precise and accurate for quantification of the main components of EO-Tv in the formed EC. Once the analytical method was validated, it was established that the encapsulation efficiency was greater than 50% in the case of NC-EO-Tv purified via evaporation at reduced pressure. On the other hand, 35.78 μg cm−2 of thymol was quantified in the EC formed from the NCs and AL. The present work presents an analytical tool for simultaneous quantification of the main components of EO-Tv in NCs, as well as in the ECs formed with NCs, promoting its potential application in fruit and vegetable products.
Abstract
The spray is the primary method to apply pesticides to the crops. To provide enough coverage and deposition on target surfaces, the drop size produced during spray application must be precisely calibrated; nevertheless, it must not be too tiny to cause the undesirable phenomena known as “spray drift”. Spray drift is the movement of droplets in the atmosphere during or after spraying. The negative effect of spray drift can harm human health, livestock, and adjacent crops or can cause environmental pollution. To address this problem, a lot of work has been done. Previous studies on spray drift reduction approaches including factors promoting drift, drift measuring technologies, drift prediction models, and drift reduction technologies, were reviewed in this paper. Based on the literature review, future research and developments are projected. This review may provide guidance and reference to researchers for further development and improvement in drift reduction technologies.
Abstract
Sumiprempt containing Pyriproxyfen and fenpropathrin insecticides is used for pest control in okra crop. Pyriproxyfen can disrupt endocrine function, while fenpropathrin disrupts voltage-gated sodium channels in neurons. Based on their health risk to consumers and impact on environmental deposition, an experiment under field was planned to evaluate deposition, decontamination and related dietary risks. A methodology was developed and validated to identify and quantify the pyriproxyfen + fenpropathrin residues, extracted via QuEChERS method using GC-MS/MS. The foliar application of ready-mix formulation (Pyriproxyfen 5% + Fenpropathrin 15% EC) @ 750 gm mL−1 ha−1 and 1,500 gm mL−1 ha−1 leads average initial deposition pyriproxyfen 5% (0.359, 0.584 ppm) and fenpropathrin (0.643, 1.005 ppm) at respective doses. Residues reached below limit of quantification (0.01 ppm) on 15th and 20th day for pyriproxyfen and 10th and 15th day for fenpropathanin at the recommended and double the recommended doses, respectively. Dissipation followed the first-order kinetics with half-life value ranged in between 1.79–1.84 (pyriproxyfen) and 2.27–2.31 days (fenpropathrin) at the respective doses. The pre-harvest interval of 12 days was recommended for safe consumption of okra fruit. Even though all the decontamination treatments were successful in lowering the residues of both chemicals to substantial levels, washing followed by boiling was found to be the most effective treatment for reducing the residues. The risk quotient values were less than 0.01, implying that pyriproxyfen and fenpropathrin offer no dietary risk to consumers.
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.
A hazai láptalajok osztályozás-története és az osztályozás továbbfejlesztése
History of classification of bog soils in Hungary and a proposal for the further development of classification
A vitaalapnak szánt dolgozat bemutatja a hazai láptalajok kutatás- és osztályozás történeti (kronológiai) fejlődését 1859-től napjainkig. A bemutató ismertetés, kritikai elemzés kiemeli az osztályozás fejlődése, és a genetikus, talajföldrajzi osztályozás kialakulása szempontjából fontos eredményeket. Meghatározza a kialakult osztályozás továbbfejlesztését képező ismereteket, amelyek a következők (DÖMSÖDI, 2015; DÖMSÖDI, 1988):
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A „láp” és a „láptalaj” képződés genezise: folyamata, szakaszai, típusai
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A láptalajok talajképző tényezői:
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2.1 Az egykori láp környezetének éghajlati viszonyai (főként éghajlati, klimatikus tényező).
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2.2 A láp élővilág jellege: rétláp, mohaláp, al-láp, fel-láp, (ökológiai fejlődéstörténeti) és növényzete (vegetáció) tényező.
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2.3 A láp felszínalaktani jellege és geomorfológiai helye (síkláp, dombláp, völgyláp, medenceláp), domborzati tényező.
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2.4 A láp, illetve a talaj kora (földtörténeti; abszolút, relatív kortényező).
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2.5 A láp, illetve a talaj földhasználata: rét, legelő, erdő, szántó művelése (antropogén hatások tényezője).
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A láptalajok típusai, altípusai, az altípusok típusszelvényei, mindezek definíciói és dimenziói.
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.
Abstract
During the testing of laboratory Voriconazole API batches, one unidentified impurity (IMP-5.312) was detected employing the Pharmeuropa HPLC technique at a level in excess of 0.10%. This IMP-5.312 was synthesized and then characterized as 6-(3-(2,4-difluorophenyl)-3-hydroxy-4-(1H-1,2,4-triazol-1-yl) butan-2-yl)-5-fluoropyrimidin-4-ol by the corresponding spectral information (MS, 1H-NMR, 13C-NMR, and IR). The IMP-5.312 impurity was effectively quantified using an enhanced HPLC based-technique that was developed as well as validated. The approach made use of a Novapak C18 column with an inner diameter of 3.9 mm and a length of 150 mm (4.0 µm) for chromatographic separation. The analysis of IMP-5.312 was made at 45 °C, with a flow rate (isocratic) of 1.0 mL min−1 and a 256 nm detection wavelength. Acetonitrile, methanol, and 0.1% aqueous trifluoro acetate buffer (pH 4.0) were mixed at a ratio of 15:30:55 (v/v/v) to create the mobile phase for a 20 μL sample injection. The linearity range of 0.25281–1.51690 μg mL−1 had a correlation coefficient more than 0.99942, and the accuracy ranged from 89.3 to 100.3%. It was noted that the established HPLC based-technique was sensitive, specific, and precise. The technique was executed on the current batches of VRC API for IMP-5.312 analysis, and the outcomes were good. For quality control purposes during the manufacturing procedure of VRC, the identification as well as analysis of IMP-5.312 should be helpful. The in silico approach was applied to predict the IMP-5.312 toxicity. The reports indicated that IMP-5.312 in non-mutagenic and categorized as ICH M7 class-5 impurity.
Abstract
In this investigation, a rapid and reliable ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) technique was developed for quantification of veliparib in rat plasma and used the method to study the pharmacokinetics and bioavailability of veliparib in rats after oral (6 mg kg−1) and intravenous (2 mg kg−1) administration. Plasma samples were protein precipitated with acetonitrile using midazolam as internal standard. A UPLC HSS T3 chromatographic column was utilized for separation, with a mobile phase consisting of methanol-water-formic acid in gradient elution procedure. Quantitative analysis was performed using multiple reaction monitoring in electrospray positive-ion mode. Veliparib exhibited excellent linearity within the 1–1,000 ng mL−1 range (r > 0.99). The intra- and inter-day precision of veliparib were both within 15%, and the accuracy ranged from 93.7 to 107.7%. The average recovery was above 86%, and the matrix effect was 89.0–95.8%. The AUC(0-t) values for oral and intravenous administration were 1014.7 ± 42.9 and 647.2 ± 85.2 h ng mL−1, respectively, resulting in a bioavailability of 52.3%. The UPLC-MS/MS method established in this study featured a low sample injection volume, a low quantification limit, a short chromatographic runtime, high sensitivity, and selectivity. The developed method can be used for the pharmacokinetic analysis of veliparib in both preclinical and clinical studies.
This study assesses the elemental composition of Egyptian glauconite sediments, focusing on potentially toxic elements (PTEs) and macronutrients. The primary aim is to evaluate the feasibility of utilizing these sediments as a natural source of potassium for agricultural purposes, besides conventional chemical fertilizers like potassium sulfate. To quantify elemental content, chemical analysis was employed across five distinct grain size fractions after grinding glauconite rock. The assessment included potassium, calcium, sodium, and PTE concentrations, utilizing potassium chloride (KCl) and ammonium acetate lactate (AL Solution) as single extractants, and the BCR extraction protocol, in addition to measuring the pseudo-total content of these elements. Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) facilitated a comparative analysis of elemental concentrations. Results indicate PTE concentrations within European Union regulations, with an absence of cadmium. Glauconite samples contain approximately 3–3.3% potassium by weight, alongside significant amounts of essential macronutrients (calcium, magnesium) and micronutrients (copper, nickel, zinc) crucial for agriculture. BCR sequential extraction protocol results closely align with or slightly surpass pseudo-total content results. Notably, the AL Solution demonstrates high efficiency compared to KCl or acetic acid in the first step of the BCR method. BCR sequential protocol provides valuable insights into various elemental forms and potential mobility. Overall, this study reveals that glauconite has the potential to serve as a promising alternative potassium fertilizer without causing adverse environmental impacts.
Abstract
Monitoring medications in biological fluids is an essential aspect of patient care, particularly in cases of altered mental status where accurate diagnosis, effective treatment, and even forensic examinations are crucial. In this study, a new approach combining hydrophobic-deep-eutectic and solvent-bar-microextraction (HDE-SBME) followed by a high-performance liquid chromatography-diode array detector (HPLC-DAD) was developed for the simultaneous determination of desipramine, clomipramine, as antidepressant and carbamazepine as antiepileptic agents in untreated human urine and plasma samples. The HDE solvents, synthesized using various ratios of menthol and fatty acids, were utilized in the SBME setups. Computational methods were employed to predict the structure and modes of interaction between HDE and the chosen analytes. Central composite design methodology (CCD) was used for multivariate optimization of the effects of different parameters influencing the extraction efficiency of the proposed method. Under optimized experimental conditions, the calibration graph of the spiked selected drugs in urine and plasma samples demonstrated excellent linearity (R 2 ≥ 0.994), with limits of detection/quantification below 0.60/2.02 μg L−1. The extraction recoveries achieved were 88–97%, and the repeatability/reproducibility (RSD%, n = 5) was less than 6.12/7.57. The proposed method was successfully applied to determine selected drugs in patients' urine and plasma samples. The proposed method detects three drugs in patients' urine and plasma samples without using toxic volatile organic solvents. The proposed microextraction technique exhibited a confident sensitivity, feasible operation, and simplicity compared with other published methods. Thus, it can be considered a promising method for monitoring the therapeutic levels of specific antidepressant and antiepileptic drugs in urine and plasma samples.
Abstract
The primary objective of the present inquiry is to formulate a sustainable method employing Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) for determination of Amlodipine (AM) and Irbesartan (IRB) simultaneously, compounds commonly prescribed for hypertension treatment. Existing literature underscores the absence of a comprehensive method in this regard. This research endeavors to align with the tenets of green chemistry by seamlessly integrating Analytical Quality by Design (AQbD) with RP-HPLC, replacing environmentally hazardous chemical modifiers with eco-friendly solvents. Identifying the critical variables as the 70% ethanol level and flow rate, a central composite design is applied for optimization. The separation is achieved utilizing a Phenomenex Luna column (C 18 , 250 mm × 4.6 mm i.d, 5 μm) with a mobile phase comprising ethanol and 0.1 % o-phosphoric acid in a 70:30 v/v ratio, flowing at 0.8 mL min−1, and detection wavelength of 242 nm. Green assessment methodologies are implemented to gauge the adherence of the proposed RP-HPLC method to eco-friendly principles while ensuring efficiency in chromatographic performance. The current developed method is rapid with retention time of 2.3 and 3.3 min for AM and IRB respectively and having a wide linear range from 55 to 130 μg mL−1, which makes the suitable for the accurate quantification of AM and IRB simultaneously in bulk and tablet dosage form, there by minimize environmental impact by providing a conscientious choice for the routine analysis which is achieved through the amalgamation of AQbD with a sustainable approach.
Abstract
SZJ-1207 is a natural product extracted from Stephanotis mucronata (Blanco) Merr which has significant antidepressant effects in various depression mouse models, without obvious acute toxicity or sedative-hypnotic side effects. The aim of this study was to preliminarily clarify the pharmacokinetic characteristics of SZJ-1207 in rats after a single intragastric and intravenous administration. In this study, sensitive and reliable UPLC-MS/MS quantification methods were established and then successfully applied to the pharmacokinetic study of SZJ-1207 in rats. The linear range of SZJ-1207 were 0.5–400 ng mL−1 in plasma, feaces, bile and 20–4,000 ng mL−1 in urine, respectively (r > 0.99). All methods met the requirements of ICH M10. The results of pharmaconetic study showed that Cmax, AUC(0-t) and AUC(0-∞) had linear relationships with the administered doses in the range of 0.5–4.5 mg kg−1. There was a significant gender difference in the AUC (0-t) of 0.5 and 1.5 mg kg−1 and Cmax of 1.5 mg kg−1 after ig (P < 0.05). The excretion rates of SZJ-1207 were 8.46 ± 4.82% in feces, 1.89 ± 1.08% in urine, and 0.179 ± 0.118% in bile. The oral absolute bioavailability of SZJ-1207 was calculated as 64.64%.
Abstract
Objective
The levels of fraxetin, fraxin, and dimethylfraxetin in rat plasma to be measured using an ultra-performance liquid chromatography tandem mass-spectrometry (UPLC–MS/MS) technique and applied to their pharmacokinetics and bioavailability.
Methods
The protein precipitation technique was applied to the plasma preparation using acetonitrile and methanol (9:1, v/v). At a flow rate of 0.4 mL min−1, the elution time was 6 min. The mobile phase consisted of acetonitrile-water with 0.1% formic acid, and the chromatographic column was UPLC HSS T3 (50 mm × 2.1 mm, 1.8 μm). Quantitative analysis was conducted using multiple reaction monitoring (MRM) mode and detection was performed using electrospray ionization (ESI) positive ion mode. In each group, six rats were treated with fraxetin, fraxin, and dimethylfraxetin either orally (5 mg kg−1) or intravenously (1 mg kg−1).
Results
The calibration curves showed good linearity in the range of 2–4,000 ng mL−1, where r was greater than 0.99. The bioavailability of dimethylfraxetin, fraxin, and fraxetin was determinated to be 19.7, 1.4, and 6.0%.
Conclusion
The established UPLC-MS/MS method for determining the levels of these three compounds in rat plasma was successfully applied to the pharmacokinetics of dimethylfraxetin, fraxin, and fraxetin, and the bioavailability was calculated.
Abstract
The article evaluates how well the goals of the European Green Deal are justified, especially considering the risks to energy and food security arising from the conflict between Russia and Ukraine. We agree with the objectives of the European Green Agreement as a whole, but whether some of the objectives which feature in the EASAC study can be achieved by 2030 is questionable, and the description of the tools necessary to achieve the objectives is incomplete. Among other things, there is hardly any mention of the role played by precision farming with digitalization, which is a revolutionary change from an ecological and economic point of view, in reducing the use of synthetic inputs, in regenerating the original state of the soil, in reducing GHG emissions, thus in increasing biodiversity, and at the same time in intensifying production, and finally in expanding the application of biotechnology. We examine these areas in our analysis. Some of the objectives of the EASAC study to be achieved by 2030 are subject to debate, and the description of the information and communication conditions necessary to achieve the objectives is incomplete. The IoT (Internet of Things) responds to global and local challenges: it integrates the precision technologies, WSNs (Wireless Sensor Networks), artificial intelligence, mobile field (Smart Small Robots) and remote data loggers (UAVs: Unmanned Air Vehicles and satellites), Big Data, and cloud computing. Consequently, decision support is increasingly developing into unmanned decision making. IoT (Internet of Things) is the basis of “Farm to Fork” and “Lab to Field” monitoring approaches.
This article evaluates the implementation of European Green Agreement objectives in light of energy and food security risks arising from the Russia-Ukraine conflict. While overall support for the agreement exists, the feasibility of certain EASAC study objectives by 2030 is called into question due to insufficient tools specifications. Notably absent is the emphasis on precision farming with digitalization, which is a transformative ecological and economic practice. Our analyses look into its function in reducing synthetic inputs, soil regeneration, GHG emission reduction, biodiversity enhancement, production intensification, and biotechnology development. Debates surround EASAC study objectives for 2030, despite limited information and communication restrictions. The Internet of Things (IoT) arises as a solution, combining precision technology, WSNs (wireless sensor networks), AI (artificial intelligence), smart small robots, UAVs (unmanned aerial vehicles), satellites, big data, and cloud computing. As a result, decision support turns toward unmanned decision-making, with IoT laying the groundwork for “Farm to Fork” and “Lab to Field” monitoring systems.
The use of organic fertilization is declining in Hungary due to the sharp fall of livestock stand since the middle of the 1980s. Most farmers are forced to use solely chemical crop enhancers. A bifactorial small plot experiment was carried out between 10 May 2023 and 19 October 2023 in Keszthely, in order to examine the effects of farmyard manure (M), green manure (GM) and stem residues (SR) on the nutrient uptake and nitrogen utilization efficiencies of maize at equidistantly increasing (0–70–140–210–280 kg N ha–1) nitrogen doses. The relationship between some vegetative traits (dry biomass weight, Leaf Area Index (LAI)) and yield, furthermore leaf relative water content (RWC) was also examined. According to the results, organic fertilizer substitution significantly increased the N content both in whole plant and grain samples of NPK+M and NPK+GM+SR treatments, compared to the chemically fertilized control (NPK). In case of P and K only slight differences were observed. Whole plant K contents of NPK+M were significantly higher than in the other treatments (P = 0.045; P = 0,005), furthermore P contents in grain samples were significantly higher in NPK+M (P = 0.004) and NPK+GM+SR (P = 0.05) than in control. Harvest index (HI [%]) of NPK+M and NPK+GM+SR were 1.06 and 1.05 times higher than in NPK. Depending on the treatment, P0023 maize hybrid absorbed 58.7–74.64% of total N uptake in the grain (HIN%), and the utilization of 1 kg N fertilizer for the extra yield above the yield of the individual control was 0.39–1.38 kg (AREN). Significant positive correlations were observed between dry biomass weight and yield (NPK: r = 0.937, P = 0.019; NPK+M: r = 0.971, P = 0.006; NPK+GM+SR: r = 0.88, P = 0.049), furthermore LAI and yield (NPK: r = 0.9, P = 0.037; NPK+M: r = 0.983, P = 0.003; NPK+GM+SR: r = 0.784, P = 0.117). Highest RWC values – which may be related to better soil aggregate stability – were measured in NPK+GM+SR treatment, therefore there may be a great potential in this treatment among drought conditions. The effect of organic amendments is particularly noticeable with smaller nitrogen doses so they should be used to reduce inorganic fertilizer application and the resulting environmental risks.
Abstract
A simple, fast and selective analytical method has been developed for the simultaneous determination of allantoin and D-panthenol in cosmetic products containing Aloe vera extracts. The proposed method depends on reversed-phase liquid chromatography with isocratic flow profile of the mobile phase composed of acetonitrile–10 mM phosphoric acid (pH 2.5) (85:15, v/v), with a C18 column at 30 °C. The analytes were detected with UV–vis. detector at 210 nm. The injection volume was 20 μL. The linearity ranges were found to be 0.2–20 and 0.1–10 μg mL−1 for allantoin and D-panthenol, respectively. LOD values were found to be 0.07 μg mL−1 and 0.03 μg mL−1, LOQ values were found to be 0.2 and 0.1 μg mL−1 for allantoin and D-panthenol, respectively. No interference was observed from concomitants. The developed method was applied to the analysis of 10 different type cosmetic products. It is foreseen that the method will be able to be used in order to carry out routine analysis, quality control and standardization in cosmetic products containing allantoin and D-panthenol.
Abstract
A simple, rapid, and green high-performance liquid chromatography-mass spectrometry (HPLC-MS) method was developed for determination of tauroursodeoxycholic acid (TUDCA), taurocholic acid (TCA), and taurochenodeoxycholic acid (TCDCA) in bio-transformed Jindanfen (BTJDF), which is obtained from chicken bile through a bioconversion process. The sample was prepared using water. The HPLC separation was operated on a poroshell 120 EC-C18 column with a 2.0 min gradient elution procedure. Detection was performed on a single quadrupole mass spectrometer in negative mode with selected ion monitoring mode (SIM). This developed HPLC-MS method presented good linearity (r > 0.997) and sensitivity (limit of quantification, 30.0–80.0 pg) for three analytes. The relative standard deviations (RSDs) for precision, repeatability, and stability were all below 3.00%. The matrix effects and average recoveries of three analytes were 91.2–97.9% (RSDs < 1.50%) and 95.4–103% (RSDs < 3.00%), respectively. The average contents of TUDCA, TCA, and TCDCA in ten batches of samples were 33.8, 13.2, and 20.5%, respectively. Finally, the greenness of the developed method was validated by Analytical Eco-Scale and Complex-GAPI. The developed method was proved to be an eco-friendly, effective, and reliable approach for assaying the three cholic acids in BTJDF, which is help to improve the quality evaluation level of the BTJDF industry.
Abstract
The current technologies for substandard and counterfeit drug detection are either too expensive for low-resource settings or only provide qualitative or semi-quantitative results. GPHF minilab™ is one of them based on thin layer chromatography(TLC) principles with a semi-quantitative capability by visual observation of the spot area and intensity for medicine quality analysis. Thus, its use as a quality control tool for pharmaceutical products has limitations as spot area and intensity visual observation by the naked eye highly varies from analyst to analyst. As such, in this study, the semi-quantitative technique has been transferred to a quantitative approach by capturing the developed TLC plate image using an Android-based mobile phone inside a simple carton box. Then, the spot area was quantified using justTLC software. The quantitative results were compared with the-high performance liquid chromatography (HPLC) method as the golden standard. Accordingly, linearity was observed in the assayed range (80–120% label claim), and the correlation coefficients found were (R 2 = 0.958, 0.997, 0.941, and 0.956 for Albendazole, Mebendazole, Artemether, and Lumefantrine, respectively.). The values are satisfactory. The %RSDs found were less than 2% for all drugs [intraday (n = 6) (RSD = 1.17, 1.61, 1.87, and 1.64), and interday (n = 18) (RSD = 1.16, 0.72, 1.12, and 1.18) for Artemether, Lumefantrine, Mebendazole, and Albendazole, respectively]. Moreover, comparisons of results obtained from the sophisticated CAMAG UV cabinet (R 2 =0.991, 0.971, 0.946, and 0.967) and the developed simple carton box (R 2 = 0.958, 0.997, 0.941, and 0.956) for Albendazole, Mebendazole, Artemether, and Lumefantrine, respectively. The values are comparable and reveal the accuracy of the method. Robustness testings' that were performed under different altered conditions revealed the robustness of the method (RSD less than 2% for all factors). Additionally the deviations from the golden HPLC results were on average −8.62% for albendazole, −3.79% for artemether, and −4.52% for lumefantrine samples. The developed method shows a satisfactory performance capability to utilize the GPHF minilab™ as a quantitative technique for medicine quality control purposes. It will be a very useful tool in a resource-limited setting. The target method profile, which encompasses a simple, low-cost, linear, precise, robust, accurate, and quantitative GPHF minilab™ system, was obtained for Albendazole, Mebendazole, and Arthemeter lumefantine combinations (Co-artem). The proposed method was successfully applied to analyze the content of the marketed medicines in the above mentioned tablets and offered acceptable deviations from the golden HPLC method. Automation of quantitative GPHF minilab™ was highly recommended to enhance the appropriateness and use of this system.
Abstract
Due to the frequent use of paracetamol formulations, it is useful to develop an analytical technique for the determination of intact paracetamol in presence of other drugs and excipients or the degradation products. In this study, a simple, isocratic, fast, specific, accurate and precise stability-indicating high performance liquid chromatography (HPLC) method has been developed and validated for simultaneous quantitative determination of paracetamol (PCM) and potassium sorbate (PS) in oral liquid formulations. The chromatographic separation was achieved on Zorbax SB C18 column (150 × 4.6 mm, 5 µm) with Zorbax SB C18 precolumn (12.5 × 4.6 mm, 5 µm) using distilled water pH 2 with ortho-phosphoric acid and acetonitrile (70:30, v/v) as a mobile phase, and UV detection at 235 nm. The temperature of the column was kept constant at 25 °C. The method was validated according to International Conference on harmonization (ICH) guidelines. The method demonstrated excellent linearity, with a correlation coefficient of 0.9996 and 0.9998 for PCM and PS, respectively, over the concentration ranges of 10–600 μg mL−1 (PCM) and 6–500 μg mL−1 (PS). The retention time was found to be 1.98 and 4.86 min for PCM and PS, respectively. Oral liquid formulation samples were subjected to various stress conditions (acidic and alkaline hydrolysis, as well as oxidative, heat and photolytic degradation) for the purpose of forced degradation study. The major degradation of paracetamol was achieved in acidic and basic stress conditions, while thermal and photolytic degradation generally had the least influence. On the other hand, potassium sorbate was highly susceptible to photolytic degradation. It was also shown that the formulation has strong influence on stability of tested compounds. Forced degradation studies demonstrated the stability-indicating power of the method and can be used to assess the stability of paracetamol and potassium sorbate in oral liquid formulations.
Abstract
Baricitinib (BRT) is a drug substance with potent anti-inflammatory activity indicated in rheumatoid arthritis, atopic dermatitis, severe alopecia areata and recently for the treatment of Covid-19. Process impurities of the drug during its formulation are quite known, however studies regarding its degradation products (DPs) under stress conditions are limited. In this study, the drug was subjected to forced degradation under various degradation conditions, including acidic hydrolysis, alkaline hydrolysis, oxidative and thermal, to determine its inherent stability. To this purpose, a novel HPLC method was developed for the determination of degradation impurities of BRT. Alkaline hydrolysis test showed a selectivity towards breaking C–C bonds. This resulted to five DPs formed by chain scission reactions occurred at the pyrrolo-pyrimidine group between C6–C10 and C8–C9. Also, the ethylsulfonyl-azetidin-ylidene group was subjected to C–C bond cleavage at C12–C15 and C16–C18. Degradation products were further characterized with the use of liquid chromatography quadrupole time of flight tandem mass spectrometry (LC-Q-TOF-MS/MS).
Abstract
A gradient high-performance liquid chromatography (HPLC) method has been developed to determine the concentrations of latanoprost (LP) and latanoprost free acid (LPA) in aqueous solutions. It is novel due to a combination of its simplicity, speed, and detection capability in aqueous solutions for both active drug (LPA) and prodrug (LP). This method is applicable for the research and development of novel drug delivery devices and quality control assays for experimental and commercial laboratory settings, as it allows for a high sample throughput. Samples were chromatographed across a C18 + 2.7 µm 4.6 × 7.5 mm reversed-phase column with gradient elution using a mobile phase of aqueous acetic acid (pH 3.1) and acetonitrile with 0.1% acetic acid. UV spectrophotometry was used to monitor the eluents at 210 nm. Drug concentrations from 1.0 to 150 μg mL−1 were tested, with good linearity observed across the range. LPA had a signature peak at approximately 4.82 min (SD < 0.08) and LP at 9.27 min (SD < 0.07). For both drug and pro-drug, LOD and LOQ were 1.0 and 2.5 μg mL−1, respectively. This assay which accurately measures both prodrug and drug in a single injection, has significant applicability in determining the release kinetics of novel LP drug delivery systems.
The rice plant is sensitive to soil salinity. Calcium (Ca) acts as an ameliorative agent that helps plants induce salt tolerance. This study was carried out with a comparison of the ameliorative effect of calcium on salt-stressed rice seedlings, the determination of the role of salt-responsive protein groups, and the analysis of their genetic expressions in 21-day-old rice seedlings of ten locally cultivable varieties of West Bengal. For this study, 15-day-old seedlings were treated with 200 mM of sodium chloride (NaCl) solutions along with 10 mM of calcium sulfate (CaSO4) treatment. The determination of the relationship between the salt-responsive proteins and the analysis of the gene expression of those corresponding proteins were not carried out earlier on the selected ten locally cultivable rice varieties of West Bengal. The NaCl crystals were visible on the abaxial leaf surface of salt-stressed rice seedlings. The superoxide dismutase activity was increased in rice varieties, and a similar result was also expressed with calcium treatment. The fourier transform infrared spectroscopy-attenuated total reflection spectral result gave strong evidence for the presence of several salt-tolerant proteins and their genetic expression. STRING database results have suggested that the calcium treatment, coupled with the expression of the CBL4 protein, has regulated the P5CR protein of proline biosynthesis for better salt tolerance and osmotic protection. The quantitative real-time polymerase chain reaction and SDS-PAGE gel electrophoresis analysis showed that salt-tolerant varieties, Chinsurah_nona_1, and Jarava had high calcium signaling mechanisms and osmo-protection abilities.
Abstract
The advection-convection models (ACM) have practical applications in the investigation of separation processes, where mass (heat) is transferred by convection and diffusion (dispersion) along mass/heat exchanger, eq. adsorption, chromatography column, tubular reactor, etc. The ACM consists of nonlinear partial differential equations which can be solved only with numerical methods. In the article, a comparison of the volume method (VM) and orthogonal collocation on finite elements (OCFE) is presented in terms of their reliability, accuracy of calculations, and speed of calculation. The OCFE proved to be more robust than VM.
The linear ACM model for the chromatography column has an analytical solution in the form of the equation for the number of theoretical plates (N). This equation is often applied in the interpretation and evaluation of model parameters. However, the versions of N equation published in the literature are not correct. The error can lead to significant imprecision for specific cases. Here, in the paper, the revised equations are presented and discussed for the most frequently used chromatography column models.
Abstract
This study attempted to optimize pectin extraction from queen pineapple (Qp) peels using microwave-assisted method. A three-factor factorial experimental design was employed to test the interaction of moisture content of pineapple peel, pH of the citric acid solution and extraction time. The three-way interaction among the factors has a significant effect on pectin recovery. Two-way interaction between moisture content and pH level, as well as pH level and extraction time caused significant difference in the pectin recovery. Pectin recovery increases with lower moisture content while longer extraction time does not significantly increase pectin recovery. The optimum combination of the parameters is 12% moisture content, pH level 2 of the citric acid solution, and extraction duration of 2 min, which yielded 1.01 ± 0.01% pectin recovery. This is lower than the results from previous studies on pineapple with 3.88–13.06% pectin recovery using acid extraction method. Hence further optimization is recommended.
Abstract
Plant protection products (PPP), crucial for agricultural production, are experiencing increased global demand, particularly with the growing need for food production. To meet this demand, robust analytical methods are essential for confirming the presence and determining active substance concentrations in PPP. This study introduces an analytical method utilizing high-performance liquid chromatography with a diode array detector (HPLC-DAD) for determination of acetamiprid in water-soluble powder formulations. The method, validated according to SANCO/3030/99 rev.5, demonstrated exhibited adequate accuracy and precision, with repeatability expressed as the ratio of the standard deviation (% RSD) to the relative standard deviation (% RSDr) being lower than 1. Recoveries for the active substance at concentrations above 10% ranged from 97% to 103%. The developed method is also characterized by suitable linearity, confirmed by a correlation coefficient >0.99. Specific chromatographic profiles were generated, and acetamiprid content in 180 formulations was analyzed, including reference products. The developed method aligns with “green chemistry” principles, minimizing solvent use and emphasizing energy efficiency. Overall, it offers a comprehensive approach for qualitative and quantitative analysis, ensuring the reliability of PPP quality control.
Pilóta nélküli légi járművek alkalmazása a vizes élőhelyek modern felmérésében
Application of unmanned aerial vehicles as modern tools for wetland monitoring
A vizes élőhelyek a vízi és a szárazföldi ökoszisztémák között elhelyezkedő, igen változatos, és általában nehezen lehatárolható területek. Kiemelt jelentőségük annak köszönhető, hogy bár csak a globális szárazföldi területek mintegy 6–7%-át borítják, kulcsfontosságú szerepet játszanak az éghajlat szabályozásában, a vizes ökoszisztémák biodiverzitásának és hidrológiai viszonyainak fenntartásában, valamint számos további ökológiai és társadalmi funkciót is szolgáltatnak, beleértve az árvízvédelmi, víztisztítási, szén-dioxid-tárolási, élőhelytámogatási és kulturális, rekreációs előnyöket. A vizes élőhelyek azonban mind természetes, mind antropogén hatások következtében térben és időben is dinamikusan változnak, ezért védelmük és megfigyelésük napjainkra igen fontos kutatási területté nőtte ki magát. A műholdas távérzékelés nagyobb területek egyidejű megfigyelését teszi lehetővé, azonban érzékeny a felhőzetre és a légköri hatásokra, bizonytalanságot okozva ezzel az eredményekben. A hagyományos monitoring technológiák mellett a pilóta nélküli légi járművek térnyerése egyre kifejezettebb, köszönhetően rugalmasságának, hatékonyságának és alacsony költségének, miközben nagy térbeli és időbeli felbontású, szisztematikus adatszolgáltatásra képes. Tanulmányunk a pilóta nélküli légi járművek alkalmazási lehetőségeibe nyújt betekintést a vizes élőhelyek felmérésében, valamint áttekinti és összehasonlítja az egyéb távérzékelés technológiák alkalmazhatóságát ezen területek megfigyelésében. Célja, hogy elősegítse a dróntechnológia további terjedését és széles körű alkalmazását a vizes élőhelyek monitorozásában.
Abstract
In this work, an assessment of effective solvents and extraction methods was carried out to recover the bioactive compounds from hawthorn fruit (Crataegus monogyna Jacq.). Extractions assisted by heat, microwave, and ultrasound were carried out using various organic solvents (methanol, ethanol, and isopropanol). pH differential, Folin–Ciocalteu's, and aluminum chloride methods were used to determine total monomeric anthocyanin (TMA), total phenolic compound (TPC), and total flavonoid content (TFC), consecutively. Ferric Reducing Antioxidant Power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl Hydrate (DPPH), and 2,2′- azino- bis (3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) assays were used to measure the antioxidant activity (AA) of the extracts. The outputs revealed that extraction methods and solvents significantly affect anthocyanin concentration, TPC, TFC, AA, and color values of hawthorn fruit extracts. Due to the highest recovered TMA (0.152 ± 0.002 mg ECy3Gl/g of dry weight), TPC (49.14 ± 0.38 mg gallic acid equivalents/g of dry weight), and TFC (18.38 ± 0.19 mg quercetin equivalents/g of dry weight) contents, the ultrasonic-assisted extraction is superior to heat and microwave-assisted extractions. Accordingly, it was also observed that the methanol solvent is more profound than ethanol and isopropanol. Further, the bioactive compounds' content and the extracts' antioxidant activity are shown to be highly correlated. Thus, hawthorn extracts are considered to have antioxidant properties because of their concentrated bioactive compounds.
Abstract
Venetoclax is the first oral Bcl-2 inhibitor with high affinity targeting tumor cell apoptosis mechanism. In this study we developed a simple, sensitive and reliable LC–MS/MS method to determine venetoclax in children's hemolytic or lipemic samples. The method utilized an electrospray ion source and operated in multiple reaction monitoring mode. Venetoclax-d8 was used as an internal standard. Plasma samples were precipitated by acetonitrile containing 10% dimethyl sulfoxide and were separated by a Hypersil GOLD column (2.1 mm × 150 mm, 5 μm). The mobile phase consisted of acetonitrile-2 mM ammonium acetate (30:70, v/v) containing 0.4% formic acid. The quantification for venetoclax and venetoclax-d8 were m/z 868.1 → 636.1, m/z 876.1 → 644.1, respectively. The linear range was 10–2,000 ng mL−1 for venetoclax. The matrix in normal plasma, hemolytic or lipemic plasma had no significant effect on the detection results. The specificity, recovery and stability also met the acceptance criteria of guiding principles for the validation of biological sample quantitative analysis presented in the Chinese Pharmacopoeia (2015). As a result, this method is particularly suitable for determining venetoclax in hemolytic or lipemic samples from children with acute myeloid leukemia. The method, with the application of monitoring drug concentrations in pediatric patients, was successful.
Abstract
Due to the relative independence from the operational parameters, the linear retention indices (LRIs) are useful tool in gas chromatography-mass spectrometry (GC-MS) qualitative analysis. The aim of the current study was to develop a multiple linear regression (MLR) model for the prediction of LRIs as a function of selected molecular descriptors. Liquid injection GC-MS was used for the analysis of Essential oils (Rose, Lavender and Peppermint) separating the ingredients by a semi-standard non-polar stationary phase. As a result, a sum of 103 compounds were identified and their experimental LRIs were derived relying on reference measurements of a standard mixture of n-alkanes (from C8 to C20). As a next step, a set of molecular descriptors was generated for the distinguished chemical structures. Further, a stepwise MLR was applied for the selection of the significant descriptors (variables) which can be used to predict the LRIs. From an exploit set of over 2000 molecular descriptors, it was found that only 16 can be regarded as significant and independent variables. At this point split validation was applied: the identified compounds were randomly divided into training (85%) and validation (15%) sets. The training set (87 compounds) was used to derive two MLR models by applying i) the ‘enter’ algorithm (R 2 = 0.9960, RMSЕ = 17) and ii) the ‘stepwise’ one (R 2 = 0.9958, RMSЕ = 17). The predictive power was assessed by the validation set (16 compounds) as follows i) q2 F1 = 0.9896, RMSE = 25 and ii) q2 F1 = 0.9886, RMSE = 26, respectively. The adequateness of both regression approaches was further evaluated. Newly developed headspace-solid phase microextraction (HS-SPME) procedures in combination with GC-MS were used for an alternative analysis of the studied Essential oils. Twelve additional compounds, not previously detected by the liquid sample introduction mode of analysis, were identified for which the values of the significant descriptors were within the working range of the developed MLRs. For the last compounds, the LRIs were calculated and the experimental data was used as an external set for assessment of the regression models. The predictive power for both regression approaches was assessed as follows: Enter RMSE = 41, q2 F2 = 0.9503 and Stepwise RMSE = 40, q2 F2 = 0.9521.
Abstract
Monitoring benzoylphenylureas (BPUs) residues in ready-to-eat vegetables is of great interest for an adequate assessment of human pesticide exposure. A rapid, inexpensive, simple, and effective method for determining 8 BPUs insecticides in tomatoes and cucumbers was developed and validated. Vortex-assisted liquid-liquid extraction (VA-LLE) followed by dispersive solid-phase extraction (d-SPE) using graphitized carbon black (GCB) for cleanup was used before LC-MS/MS analysis. Different parameters were optimized, including the type and volume of extractants, vortex time, and the type and amount of adsorbents used for cleanup. The evaluation showed that the method has excellent linearity (R 2 ≥ 0.994). The recovered 8 BPUs insecticides from spiked tomato and cucumber samples at 0.01, 0.05, and 0.25 mg kg−1 ranged from 83.2 to 105.2%, with RSD of 4.9–14.6%. The limits of quantitation (LOQs) were 0.0025 mg kg−1 (0.005 mg kg−1 for lufenuron). Within-day repeatability ranged from 3.9 to 13.9%, while between-day repeatability ranged from 8.9% to 17.7%. The optimized method was used to analyze 100 samples of tomatoes and cucumbers marketed in Saudi Arabia.
A hazai genetikai talajosztályozás megújításának szükségessége - 1.
A nevezéktan és a struktúra korrekcióra szoruló elemeinek azonosítása
The necessity of the renewal of the Hungarian genetic soil classification system - 1.
Identification of the elements of the nomenclature and structure to be corrected
A tanulmány a magyar genetikai osztályozás sok szempontból kritizált rendszerének következetlenségeit, illetve ellentmondásait elemzi azzal a szándékkal, hogy a rendszer fő jellemzőinek: a talajtaxonok elnevezésének és tartalmának megőrzése mellett szakmai párbeszédet indítson a hibák kijavításának lehetőségéről és a rendszer megújításáról.
Rámutattunk a nevében és koncepciójában genetikus, szerkezetében hierarchikus osztályozási rendszer hibrid jellegére: arra, hogy a fő genetikus szempont csak a főtípusok aggregációs szintjén érvényesül maradéktalanul, míg a típusoknál már mintegy egyharmad arányban diagnosztikus szempontok jelentik az elkülönítés alapját. Alsóbb hierarchiaszinteken (altípus, változat) pedig csaknem tisztán diagnosztikus az osztályozás. Listába rendeztük azokat a problémás típus, altípus és változati elnevezéseket, amelyek több hierarchiaszinten azonos névvel, és esetleg eltérő tartalommal fordulnak elő, illetve azonos hierarchiaszinten, de eltérő definíciókkal szerepelnek, vagy éppen szinonímnak tekinthetők, az eltérő elnevezés mögött rejlő azonos tartalom miatt. A vitacikk szándéka, hogy a kiszűrt hibák, következetlenségek széleskörű szakmai egyeztetést követően javításra kerüljenek.
Abstract
In this study, a multivariate optimization strategy was used to develop and validate a simple, rapid, accurate, cost-effective, and stability-indicative RP-HPLC analytical method for quantifying hydroxychloroquine sulphate (HCQ) in coated tablets. The validation conditions involved isocratic elution mode, using a mixture of buffer solution at pH 2.2 and methanol (74