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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.
Modern chemical engineering spearheads advances in environmental sciences, medicine, microelectronics, biotechnology, consumer products, and manufacturing by linking with chemistry, biology, physics, mathematics, and economics subjects. Chemical engineering also works in close collaboration with computer science, mechanical, electrical, and civil engineering.
All chemical engineering graduates go through various chemical engineering courses, including pure and applied mathematics, computing, physics, thermodynamics, industrial chemistry, cell biology, and dozens more. Many engineering disciplines require a degree in chemical engineering, at the very least.
Chemical engineers work in a wide range of fields, including petroleum refinery, jet fuel, diesel fuel, petrochemicals, personal-care product manufacturing, and many others. They are often concerned with resource managing, environment protection, and health and safety.
The chemical engineering journals represent a forum for original research presentations and discussion of the latest advances in chemical engineering. The papers that present novel theories and their applications to practice are especially welcome.
Different chemical engineering journals focus upon three chemical engineering aspects:
Chemical reaction engineering
Environmental chemical engineering
Materials synthesis and processing
The scope ranges from engineering aspects on a molecular level, plant level to global issues.
The common topics in these journals include treatment processes, environmental process management and control, clean process technology, kinetics, applied catalysis, control strategies, simulation and optimization of different reactor types, fundamental investigation of heat processes, reactor engineering and safety, chromatographic reactors, micro-reactors, etc.
Articles published in chemical engineering journals are peer-reviewed, which means they are of high quality and high impact. Some journals are open-access, but there are also many subscription-based publications.
The primary audience for chemical engineering journals includes academics, industry leaders, engineering students, researchers, and everyone interested in the latest findings and developments in the many fields of chemical engineering. These journals publish original papers, reviews, reports on conferences, book reviews, preliminary communications, short communications, and advertisements.
AKJournals has a collection of eight scientific journals in the field of chemical engineering. Below is a short description of each article along with the main subject fields followed by the official language of the journal:
Reaction Kinetics, Mechanisms and Catalysis – research papers on new materials in catalysis, biomimetic and enantioselective homogeneous catalysts, characterization of catalyst surfaces, and heterogeneous catalysis in English
Journal of Flow Chemistry, Journal of Radioanalytical and Nuclear Chemistry, Journal of Thermal Analysis and Calorimetry, JPC – Journal of Planar Chromatography – Modern TLC and Reaction Kinetics, Mechanisms and Catalysis are joint publications with Springer Nature.
The two chemical components Escitalopram (ESC) and Etizolam (ETZ) are beneficial for the health of individuals because it helps to treat anxiety. The study mainly illustrated that a green approach is essential in the medical sector with the help of “Green Analytical quality by design”. According to AQbD, the techniques of HPTLC have become eco-friendly, and decided to use “ESC” and “ETZ”. Hence, ethanol and phosphate buffer pH 3.5 adjusted with 1% “orthophosphoric acid”. After the retardation factor, the product ESC was found at 0.34 min and ETZ was found at 0.53 min. The linearity of ETZ the range varies from 300 to 1800 μg mL−1 and for ESC it varies from 100 to 600 μg mL−1. The validation parameter of R2 Values ranged from 0.9997 to 0.9994 for both ESC and ETZ. The study also demonstrated that different other methods were also useful for the medical sector to make it more convenient and eco-friendly. Some of those approaches are “GAPI”, “AGMS”, “NEMI”, and “AGREE”. The outcome of the study helped to find that the technique “HPTLC” is a green analytic design that helps to maintain the stability of the medicine and it was also approved as a quality design and also a novel approach in the pharmaceutical sector.
Using the Design of Experiments methodology (Response-Surface Methodology and Derringer's Desirability Function), a simple, fast and robust RP-HPLC method was developed for the analysis of enrofloxacin (EFC), its impurity A (fluoroquinolonic acid, FQ) and impurity B (ciprofloxacin, CPX). Gradient elution of samples was performed on a Zorbax Eclipse XDB C18 column (150 × 4.6 mm, 3.5 μm) with a mobile phase consisting of 32 mM phosphate buffer pH 3.5 – methanol (0 min-19.6% methanol; 15.5 min-19.6% methanol; 29.5 min-80% methanol; 30 min-19.6% methanol; 35 min-19.6% methanol), delivered at a flow rate of 1.5 mL min−1, wavelength of detection 278 nm (for EFX and CFX) and 265 nm for FQ. A good linear response was achieved in the range 15–35 μg mL−1 (EFX) and LOQ-150% for impurities (CFX and FQ). Other validation parameters were also tested: precision, accuracy, sensitivity and robustness. The developed method was shown to be simple, practical and suitable for the analysis of EFC and its impurities (CPX, FQ) in veterinary drugs.
A rapid, stability indicating reverse phase liquid chromatographic method was developed for the determination of purity of Felodipine in active pharmaceutical substance form in the presence of its impurity and its degradation products. To develop the method which is also compatible to liquid chromatographic mass spectroscopic technique. The developed method is also used to determine the assay of Felodipine in bulk drug form. The drug is subjected to various stress conditions like acidic, basic, oxidation, UV light and thermal conditions. Considerable degradation was observed during base hydrolysis. Two degradation products were identified. The Waters Acquity UPLC BEH C18, 2.1 × 100 mm, 1.7 µm Column was used to achieve chromatographic separation. The gradient conditions, diluent and injection volume were optimized to achieve the acceptable resolution between impurities and its degradation products from Felodipine and to get good peak shapes. The masses were determined for main compound and its identified degradation products. Further, the characterization studies for main compound and its degradation products were performed using LCMSMS Q-TOF.
SZJ-1207 is an antidepressant natural product with a steroidal structure extracted from Stephanotis mucronata. It is a novel antidepressant candidate molecule and all its pharmacokinetic properties have not been reported. In this pharmacokinetic study in mice following oral administration, an accurate and sensitive UPLC-MS/MS method was established and evaluated to measure SZJ-1207 concentrations in mouse plasma and brain samples. The results provide information regarding the pharmacokinetics of SZJ-1207 as a potential antidepressant.
A közösségi tudomány – citizen science – már évtizedek óta működő kutatási forma, ahol egy-egy kutatás a lakosság segítségével valósul meg. Az „Alsóban az élet” kampány az érdeklődők bevonásával 2021 tavaszán indult hazánkban. A kutatásban résztvevők kézhez kaptak egy pamut alsóneműt, amelyet kb. 20 cm-es mélységben kellett elásniuk, ezzel „táplálékot” szolgáltatva a talajlakó élőlények számára. Több mint két hónap elteltével az alsónemű kiásása után megfigyelhetők a bomlási jelek, amelyek mint indikátor jelzik a talajélet aktivitását, közvetett módon a talaj egészségi állapotát. A visszamaradt alsóneműk digitális fotójának elemzésével becsülhető a talajlakó élőlények munkája az alsónadrágok bomlásának százalékos aránya alapján.
A közösségi médiában megjelent felhívások és célzott csoporthirdetések segítségével mintegy 1193-an jelentkeztek a programra összesen 1966 helyszínnel, ezzel országos lefedettséget biztosítva a kutatás részére. Az adatok elemzése alapján a gondozott konyhakertekben elásott pamut alsók mutatták a legnagyobb átlagos bomlási értékeket (27,67%). Talajtípust tekintve a réti talajok és a közép- és délkeleteurópai barna erdő-, valamint a csernozjom-, és a váztalajok (köztük nagyrészt a humuszos homoktalajok) esetén tapasztaltuk a legmagasabb, közel azonos, 25,47%; 25,43%; 24,22%; 24,21%-os bomlási értéket. A programban résztvevő helyszínek közül a legnagyobb mértékű bomlás (93%) konyhakert hasznosítású (mulcsozott veteményes és polikultúra ágyás) váztalajon (homoktalajon) volt megfigyelhető. Az országos átlagos bomlási érték 24,57% volt. A bomlási adatok alapján eredménytérképet szerkesztettünk Magyarország teljes területére, melyet nyilvánossá tettünk, s a résztvevőknek a visszaküldött fotó feldolgozása alapján rövid, a saját talajának biológiai aktivitását minősítő válaszlevelet küldtünk.
The retention behaviour of scopolamine (hyoscine) and its related compounds (norhyoscine, atropine, homatropine, and noratropine) was investigated on the silica-based HPLC stationary phase. The retention of investigated tropane alkaloids was interpreted by using the Soczewiński-Wachtmeister equation. A high correlation between the retention parameter (log k) and lipophilicity (log P) (R = 0.9923) confirms the significant influence of hydrophobic interactions on the retention behaviour of the aforementioned compounds. It was found that by increasing the acetonitrile fraction, a decrease in retention of the more polar epoxide derivatives (scopolamine, norhyoscine) and an increase in retention of the more lipophilic derivatives (atropine, noratropine, homatropine) is obtained. The best separation of the tropane alkaloids was achieved by a simple procedure that involved a mobile phase composed of acetonitrile and 40 mM ammonium acetate/0.05% TEA, pH 6.5; 50:50 v/v. Selected conditions were assumed for the determination of scopolamine hydrochloride in the eye drops (Scopolamini hydrobromidum 0.25%). The method was validated and it was found as selective, sensitive, precise, accurate, and robust for the further qualitative analysis of the scopolamine-related compounds.
In this study, we report the systematic approach for characterization of two major degradant impurities, which are not listed in any compendia and were formed during the stability studies of Dihydroergotamine mesylate injection (DHE). An ion-pair UPLC chromatographic method was developed to quantify the related substances present in the DHE injection drug product. The same was used to monitor the impurity profiling during its stability. The two unknown impurities were observed at RRT about 0.08 (Impurity-1) and RRT about 0.80 (Impurity-5) and found to be significantly increasing on stability. Forced degradation studies revealed the nature of the impurity and conditions required for enriching them. A Mass compatible HPLC method was developed to quantify only these two impurities using 25% ammonia and formic acid in water. Their mass numbers were identified using LC MS/MS with triple quadruple mass spectrometer coupled with a HPLC. These two impurities were then isolated from enriched products using preparative HPLC. These impurities were then characterized using Mass and NMR analysis along with Q-TOF elemental analysis.
Bacterial DNA gyrase and topoisomerase IV control the topological state of DNA during replication and represent important antibacterial drug targets. To be successful as drug candidates, newly synthesized compounds must possess optimal lipophilicity, which enables efficient delivery to the site of action. In this study, retention behavior of twenty-three previously synthesized dual DNA gyrase and topoisomerase IV inhibitors was tested in RP-HPLC system, consisting of C8 column and acetonitrile/phosphate buffer (pH 5.5 and pH 7.4) mobile phase. logD was calculated at both pH values and the best correlation with logD was obtained for retention parameter φ0, indicating that this RP-HPLC system could be used as an alternative to the shake-flask determination of lipophilicity. Subsequent QSRR analysis revealed that intrinsic lipophilicity (logP) and molecular weight (bcutm13) have a positive, while solubility (bcutp3) has a negative influence on this retention parameter.
Kutatásunk témája az NCH Magyarország Kft. által forgalmazott baktériumos hígtrágyakezelési rendszer összehasonlító ökotoxikológiai vizsgálata. A kísérletet egy szarvasmarha borjúnevelő telepen végeztük 0–6 hónapos korcsoportú szekcióban. A tabletta formában rendelkezésünkre álló baktérium törzseket egy tartályban felszaporítottuk és hetente adagoltuk az aknában összegyűlő hígtrágyához. A kezelés célja volt, hogy a baktériumok elősegítsék a trágya homogenizációját, a szagcsökkentést és a szerves szennyeződések lebontását. Az ökotoxikológiai vizsgálatokat a trágyakezelés előtt, alatt és után, három mintavételi időben végeztük el.
A kutatásunk eredményeként elmondhatjuk, hogy a hígtrágyakezelés során a beltartalmi értékek jelentősen növekedtek, főként a nitrogénformák, a biológiai oxigénigény és a szárazanyagtartalom. Az ösztrogén hatás megléte számottevő maradt a kezelés végére is. A fitotoxicitási vizsgálat alapján mindegyik növény, szár- és gyökérnövekedésére pozitív hatással volt a trágyakezelés. A talajtoxicitási teszt eredménye bizonyította, hogy magasabb hígítás mellett veszti el a kezeletlen hígtrágya az érzékeny baktériumok élettevékenységére is kiterjedő gátló hatását. A békalencse vizsgálat során összességében elmondható, hogy 150× hígítás fölött megszűnik a hígtrágya gátló hatása mindhárom alkalommal vett minta esetében. Az alga növekedésgátlására a hígtrágya stagnáló-gátló tendenciát mutatott a kezelés alatt.
Eredményeink alapján arra a következtetésre jutottunk, hogy a vizsgált hígtrágyakezelési módszer a homogenitás, szagtalanítás és a szerves anyagok bontása során eredményes volt. Azonban javasolt magasabb hígítási arányban vagy magas talajvíztartalom mellett kijuttatni a földekre. A hormonhatású anyagok eltávolítására vonatkozólag további vizsgálatok szükségesek, melyek alapján majd javaslatokat lehet kidolgozni a gazdák számára.
The bark of Eucommia ulmoides and the roots of Achyranthes bidentata are commonly used in traditional Chinese medicine, and their pairing appears in many traditional Chinese medicine formulas as a recognized compatible unit. However, the changes and interactions of the main components of these two formulas when paired remain unclear, and there is currently no standard or method for their quality control and assessment of pharmacological effects.
An optimized ultra-high-performance liquid chromatography triple-quadrupole mass spectrometry (UHPLC-MS/MS) method was established for the simultaneous identification of 10 components in E. ulmoides and A. bidentata using in vitro and in vivo models. Tributyltin methacrylate was the internal standard solution, and the blood samples were treated by an organic solvent precipitation method. Gradient elution was conducted on a C18 column at 25 °C with 0.1% formic acid water:acetonitrile as the mobile phase at a flow rate of 0.5 mL min−1. Dynamic multiple response monitoring was performed in negative-ion mode using an Agilent Jet Stream electrospray ionization ion source.
In negative-ion detection mode, eucommiol exhibited a good response, and the isomers ginsenoside Ro and achyranthoside C could also be well separated. The developed method accurately detected the five components with a low blood content. Compared to controls, the levels of ginsenoside Ro, chikusetsusaponin Ⅳa, and achyranthoside C increased; the contents of geniposidic acid and pinoresinol diglucoside were unchanged; and the levels of eucommiol, geniposide, β-ecdysterone, genipin, and achyranthoside D decreased in vitro. In vivo, the contents of geniposidic acid, geniposide, pinoresinol diglucoside, and β-ecdysterone were reduced; the contents of eucommiol and ginsenoside Ro were unchanged; and those of achyranthoside D, chikusetsusaponin Ⅳa, and achyranthoside C increased compared to the corresponding levels in the internal control.
A method for the quality control of the E. ulmoides-A. bidentata drug pair was established for the first time and the main components in 10 drug pairs could be determined simultaneously in vitro and in vivo. These findings show that the E. ulmoides and A. bidentata drug pair cause a compositional change, providing new ideas for the development of this combination to improve clinical efficacy.
We developed and validated a sensitive, heart-cutting, two-dimensional liquid chromatography–tandem mass spectrometry (2D-LC‒MS/MS) method to determine the concentration of mometasone furoate in human plasma after nasal spray administration. Isotopically labeled mometasone furoate-13C,d6 was used as an internal standard (IS). Plasma samples were prepared using a solid-phase extraction (SPE) method. With this 2D-LC strategy, the analytes were trapped in the first dimension (1D) column, and only judiciously selected portions of the 1D effluent were transferred to the second dimension (2D) column for further separation to obtain high-resolution information. MS/MS quantification was performed in positive ionization mode via multiple-reaction monitoring (MRM). This analytical method was fully validated according to related regulatory guidance, and the results showed that the method is robust and sensitive enough for pharmacokinetic investigation of mometasone furoate with satisfactory linearity from 0.25 to 30 pg mL−1. This method was successfully applied to a bioequivalence (BE) study of mometasone furoate aqueous nasal sprays in healthy volunteers.
A simple, rapid, sensitive and eco-friendly liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous determination of free cordycepin (3′-deoxyadenosine) and isocordycepin (2′-deoxyadenosine) in 10 kinds of Cordyceps samples. The samples were prepared by ultrasonic extraction at 75 °C for 30 min with boiling water as the extraction solvent. The LC separation was performed on an Agilent poroshell 120 SB-Aq C18 column (3.0 × 50 mm, 2.7 μm) in isocratic mode with an eco-friendly mobile phase (2% ethanol containing 0.2% acetic acid) at a flow rate of 0.6 mL min−1, and detected by MS/MS in positive mode with multiple reaction monitoring (MRM). The developed method showed good linearity (r > 0.9990), sensitivity (LODs = 0.04 pg, LOQ = 0.1 pg), precision (RSD ≤ 3.8%) and stability (RSD ≤ 3.6%). The recoveries of developed method were 94.4–109.5% (RSD ≤ 5.5%). Compared with reported methods, the current method was rapid (less than 35% analytical time), sensitive (more than 5 folds), and eco-friendly (less than 10 μL harmful organic solvent). 10 different kinds of Cordyceps samples (40 batches) were tested by the developed method. Codycepin was only found in Cordyceps millitaris and C. millitaris fruiting body, and isocordycepin was detected in Cordyceps sinensis and other 6 Cordyceps samples. The developed method would be an improved method for the quality evaluation of Cordyceps samples.
The study was aimed to validate and optimize high performance liquid chromatographic (HPLC) method for the determination of coumarin-3-carboxylic acid (C3A) in the heart and liver issue of Sprague-Dawley (SD) rats after intragastric administration of extractive of leaves of Ficus virens var sublanceolata. And simple ADME and target prediction analyses were performed for C3A. Ethyl acetate was employed to precipitate protein with appropriate sensitivity and acceptable matrix effects. The satisfactory separation was developed on an ODS2 column (4.6 mm × 250 mm, 5 μm) by gradient elution with a methanol-acetic acid solution (pH = 3.0) as the mobile phase. The flow rate was 1.0 mL min−1, the column temperature was maintained at 30 ± 2 °C, the injection volume was 20 μL, and the detection wavelength was set as 309 nm. The method was fully validated in terms of selectivity, linearity, accuracy, precision, extraction recovery and stability. The results of the ADME analysis found that C3A has excellent characteristics of drug-likeness, consistent with good bio-absorption. And the predicted 12 target protein belongs to the amine oxidoreductase and carbonic anhydrase target class. This method is simple, rapid, sensitive, and accurate for the determination of coumarin-3-carboxylic acid in the heart and liver tissue of SD rats.
A talajok a szárazföldi széntároló rendszerek egyik legjelentősebb tagját jelentik, melyek szénelnyelése, illetve szénkibocsátása jelentős mértékben hat a klímára, ugyanakkor a klímaváltozás is befolyásolja a talajok szénraktározó képességét. Az avar produkció mennyiségi és minőségi változásai jelentősen befolyásolják ezeket a folyamatokat, azonban ezek mértéke, sőt időnként iránya sem ismert pontosan.
A klímaváltozás mellett a területhasználat változások is befolyásolják a talajba kerülő szerves anyagok mennyiségét és ezen keresztül számos egyéb talajfizikai, kémiai és biológiai paramétert. Ezeknek a hatásoknak a rendszerszintű vizsgálatát segítik a nemzetközi avarmanipulációs projektek, melyek azonos kezeléseket alkalmazva, de eltérő klímaviszonyok mellett vizsgálják a mesterségesen átalakított avar inputok hatását a talajrendszerekre. A Síkfőkút project területén, mely 2000-ben csatlakozott a nemzetközi DIRT projecthez, vizsgáltuk az avar input növekedésének és csökkenésének hatásait egy cseres tölgyes erdőben a talajok szén körforgalmára, illetve a vízháztartására. Ezeken a kutatásokon belül vizsgáltuk a kezelések talajaiban a talajnedvesség tartalmat, vízkapacitást és térfogatsűrűséget, valamint CNS analizátorral a talajok szerves szén tartalmát.
Eredményeink azt mutatták, hogy az avar produkció mennyiségi változása, éghajlati viszonyoktól függően, eltérően hat a talajok SOC tartalmának változásaira. A kezelésekkel modellezett avar produkció változások nemcsak közvetlen úton hatnak a talajok szerves anyag tartalmára, de közvetett módon a megváltozott mikroklimatikus viszonyok révén is befolyásolják a talajok szén és vízforgalmi viszonyait. A nagyobb avar produkció a szárazabb síkfőkúti erdőben növelte a talajok szén tartalmát (szemben a nedvesebb amerikai területeken tapasztalt visszaeséssel, vagy stagnálással) és magasabb szerves anyag tartalom társulva a vastagabb avartakaróval magasabb átlagos talajnedvességet és vízmegtartó képességet eredményezett az avar elvonásos kezelésekkel szemben. Ezek a hatások összefüggésben lehetnek azzal is, hogy az avarelvonásos kezeléseknél szignifikánsan magasabb térfogattömeg értékeket mértünk, ami a pórustérfogat csökkenését jelentheti ebben az esetben, csökkentve ezzel a talajban tárolható víz mennyiségét.
Az általunk végzett avarmanipulációs kísérletek nemzetközi kontextusában közelebb juthattunk a biogeokémiai ciklusok, ezáltal a mineralizáció és a humifikáció közötti összefüggések megértéséhez különböző erdőtípusokban és különböző klimatikus feltételek között.
In the present study, an LC-MS/MS method allowing to quantify pretomanid and pyrazinamide simultaneously in rat plasma was developed. Chromatographic separation was achieved on an Agilent Eclipse plus C18 column (100 mm × 2.1 mm, 3.5 μm; Agilent, USA) and maintained at 30 °C. Multiple reaction monitoring (MRM) using positive-ion ESI mode to monitor ion transitions of m/z 360.1 → m/z 175.1 for pretomanid, m/z 124.1 → m/z 81.0 for pyrazinamide, m/z 172.1 → m/z 128.1 for metronidazole (IS). The calibration curves showed good linear relationships over the concentration range of 50–7,500 ng mL−1 for pretomanid and 500–75,000 ng mL−1 for pyrazinamide. The precision and accuracy were below 15% and within ±15% of the nominal concentrations, respectively. The selectivity, recovery and matrix effect of this method were all within acceptable limits of bioanalytics. The method was applied to the analysis of plasma samples from pharmacokinetic studies in rats. The results show that the main pharmacokinetic parameters of pyrazinamide, namely, Tmax, t1/2, and AUC(0–t), decreased in the combined group than in the alone group.
Muscle relaxants and pain killers with their different types are widely used as combination approach for treatment of pain associated with several muscle spasm conditions. A sensitive and simple HPLC-UV detection method was developed in this work for simultaneous assay of Dantrolene (DNT) and co-administrated: Ibuprofen (IBU) and Diclofenac (DIC). After simple protein precipitation, separation was achieved using C18 column (150 × 4.6 mm) with a mobile phase of acidified water with orthophosphoric acid (pH = 3.5) and acetonitrile using gradient elution with a flow rate of 1 mL/min. The DAD was adjusted at 380, 219, 280 and 240 nm to measure DNT, IBU, DIC, and dexamethasone (internal standard), respectively. Linearity was demonstrated over the range from 0.1 to 3 μg/mL, 1 to 40 μg/mL, and 0.1 to 2 μg/mL for DNT, IBU, and DIC, respectively. The validated method was applied successfully to compare the effect of co-administration of IBU or DIC on the pharmacokinetic profile of DNT.
70 species of grasses family (Poaceae), coming from genera: Agrostis, Alopecurus, Anthoxanthum, Apera, Arrhenatherum, Avena, Brachypodium, Briza, Bromus, Calamagrostis, Corynephorus, Cynosurus, Dactylis, Danthonia, Deschampsia, Digitaria, Echinochloa, Elymus, Eragrostis, Festuca, Glyceria, Helictotrichon, Hierochloe, Holcus, Hordeum, Koeleria, Leymus, Lolium, Milium, Molinia, Nardus, Panicum, Phalaris, Phleum, Phragmites, Poa, Saccharum and Setaria, collected mostly from natural stands in Poland during 2020 season, were subjected to GC-MS fingerprinting of headspace volatile fraction above dried material. Obtained mass spectrometry data were analyzed by means of principal component analysis (PCA) and hierarchical cluster analysis (HCA). Five species: Glyceria maxima (Hartm.) Holmb., Lolium multiflorum Lam., Hordeum jubatum L., Bromus tectorum L. and Bromus secalinus L. were identified as outliers, which is consistent with our earlier analysis by thin layer chromatography. These species deserve further look and their outliance is orthogonal to coumarin content, which was independently observed for odorant species of grasses.
If we want to increase the efficiency of precision technologies to create sustainable agriculture, we need to put developments and their application on a new footing; moreover, a general paradigm shift is needed. There is a need to rethink close-at-hand and far-off innovation concepts to further develop precision agriculture, from both an agricultural, landscape, and natural ecosystem sustainability perspective. With this, unnecessary or misdirected developments and innovation chains can be largely avoided. The efficiency of the agrotechnology and the accuracy of yield prediction can be ensured by continuously re-planning during the growing season according to changing conditions (e.g., meteorological) and growing dataset. The aim of the paper is to develop a comprehensive, thought-provoking picture of the potential application of new technologies that can be used in agriculture, primarily in precision technology-based arable field crop production, which emphasizes the importance of continuous analysis and optimisation between the production unit and its environment. It should also be noted that the new system contributes to reconciling agricultural productivity and environmental integrity. The study also presents research results that in many respects bring fundamental changes in technical and technological development in field production. The authors believe that treating the subsystems of agriculture, landscape, and natural ecosystem (ALNE) as an integrated unit will create a new academic interdisciplinarity. ICT, emphasizing WSN (Wireless Sensor Network), remote sensing, cloud computing, AI (Artificial Intelligence), economics, sociology, ethics, and the cooperation with young students in education can play a significant role in research. This study treats these disciplines according to sustainability criteria. The goal is to help management fulfil the most important expectation of reducing the vulnerability of the natural ecosystem. The authors believe that this article may be one of the starting points for a new interdisciplinarity, ALNE.
An easy, quick, and sensitive approach adopting ultra-performance liquid chromatography (UPLC) equipped with diode array detector was used to analyze and systematically evaluate the quality of Pudilan tablets manufactured by 12 distinct pharmaceutical companies. In this research, 15 peaks were chosen as the common peaks to assess the similarities for different batches (S1–S43) of Pudilan tablet samples. In comparison with the control fingerprint, similarity values for 43 batches of samples exceeded 0.922. In addition, by analyzing the reference substances of epigoitrin, caffeic acid, chlorogenic acid, acetylcorynoline, baicalin and baicanshialein, the chromatogram of the 6 reference substances was established. The recoveries for the reference substances which demonstrated good regression in the linear range (r2 > 0.999) were in the range of 98.3–101.1%. The results demonstrated that the established method was highly accurate, efficient and reliable. This study provides a valid, dependable and pragmatic method to evaluate the quality of Pudilan tablet.
2017. októberétől 2021. októberéig terjedő időszakban vizsgáltuk egy középmagyarországi szántóföld szénforgalmát gázcseremérések segítségével. A mért nettó ökoszisztéma gázcsere (NEE) adatokból kumulált összegeket számoltunk éves bontásban, illetve az egyes növényállományok és ugar időszakok szerint. Gazdálkodási adatok segítségével számoltuk a területre behozott (import) és onnan elvitt (export) szénmennyiségeket, valamint az NEE, az import és az export áramokat összesítve szénmérleget (NECB) számítottunk az NEE összegekhez hasonló bontásban.
Az eredmények alapján a szántóföld minden évben szénelnyelőnek bizonyult, annak ellenére, hogy a vizsgált időszak során több vízhiányos periódus is hátráltatta a növények megfelelő fejlődését és ezzel a szénfelvételt. A mért éves átlagos NEE összeg –69,6 g C m–2 év–1 volt. Ezzel szemben a teljes – laterális áramokat is tartalmazó – szénmérleg minden évben és minden növényállomány esetében veszteségesnek bizonyult, átlagosan –168 g C m–2 év–1 volt a szénveszteség mértéke. Ennek a deficitnek a jelentős része a vízhiányos időszakok alatti lecsökkent szénfelvételnek köszönhető, ezt jól mutatja a két őszi búza állomány szénmérlege közötti 66 g C m–2-es különbség, ahol az első állomány jó vízellátás mellett, a második pedig vízhiányos időszak alatt fejlődött. Nedvesebb időszakban vélhetően kevésbé jelentős a szénveszteség mértéke.
A szakirodalom alapján nincs olyan módszer, amellyel önmagában kompenzálni lehet egy ilyen mértékű veszteséget, azonban több olyan eljárás is létezik, amelyek kombinációjával jó eredményeket lehet elérni. Fontos lenne a hazánkban jól alkalmazható módszerek feltárása és azok szénmérlegben játszott szerepének számszerűsítése.
Munkánk során igyekeztünk a belvízminőséggel, annak időbeli változásaival kapcsolatos kérdéseket megválaszolni.
Az eddig vizsgált nehéz agyag talajtextúrájú algyői mintaterületről származó eredmények rávilágítanak arra, hogy tápanyagok tekintetében számottevő terhelés érheti az elvezetés során a belvizet befogadó felszíni víztestet különösen a belvízelöntés kezdeti időszakában. A terhelést kiemelten a lebegőanyaghoz kötött tápanyagformák adják, míg emellett a felszíni vízborítás kialakulását követő első napokban és hetekben jelentős, környezetvédelmi határértéket is átlépő mineralizált nitrogéntartalomra is kell számítani.
A belvizes környezet reduktív jellemzőinek erősödésével a nitrát – külső utánpótlás nélkül – hamar átalakul, míg a hőmérséklet és a biológiai aktivitás emelkedésével a lebegőanyagtartalom koagulációja és flokkulációja is jelentősen csökkenti a tápanyagterhelést.
Ezen a mintaterületen képződött belvíz öntözővízként való hasznosítását az öntözőrendszer eltömődéséhez vezető magas lebegőanyagtartalom, illetve esetenként magas vas- és mangántartalom nehezítheti jellemzően szintén a tavaszi időszakban, amikor pl. kelesztő öntözéshez használhatjuk fel a vizet a magasabb térszíneken.
Általános érvényű következtetések levonásához a kutatás későbbi szakaszában két új, eltérő talajtani és hidrológiai adottságú mintaterületre is kiterjesztjük vizsgálatunkat. A helyszíni mérésekkel párhuzamosan összeállítunk egy laboratóriumi kísérletet kiemelten a talajtényező hatásának megfigyeléséhez. Ez lehetőséget fog nyújtani arra is, hogy a tápanyagformák időbeli átalakulásáról is pontosabb képet kapjunk.
Codonopsis Radix (CR) is recorded as the roots of Codonopsis pilosula, C. pilosula var. modesta and Codonopsis tangshen. It is difficult to evaluate the quality of CR because of the existence of many original plants. In this paper, a strategy integrating chromatographic analysis and chemometrics for the quality control of CR is proposed. Systematic analysis of the chemical composition of CR was achieved through high performance liquid chromatography (HPLC) fingerprinting. Based on the HPLC fingerprinting data, chemometrics, including unsupervised principal component analysis (PCA) and supervised orthogonal partial least squares-discrimination analysis (OPLS-DA), were applied to classify all CR samples. Components with variable importance in projection values higher than 1 in the OPLS-DA model were selected as potential chemical markers for distinguishing the origins of CR. Finally, an HPLC method was validated for determining the five characteristic ingredients in the CR samples. HPLC characteristic fingerprints showed 17 common peaks for C. pilosula, 13 for C. pilosula var. modesta, and 9 for C. tangshen, and all of them showed good similarity (>0.9). Additionally, there were 9 common peaks for all CR samples with relatively poor similarity, ranging from 0.607 to 0.970. PCA could differentiate CR from the three origins, except for a partial overlap between C. pilosula and C. pilosula var. Modesta, and the OPLS-DA model achieved excellent classification results. Eight components (peaks 12, 8, lobetyolin, 10, codonopsin І, syringin, 3, and 11) were selected as potential chemical markers. There was a large discrepancy in the contents of the five characteristic ingredients in all samples, with the relative standard deviation ranging from 36.0% (lobetyolin) to 85.9% (atractylenolide Ⅲ). The average contents of the five characteristic ingredients were similar between C. pilosula and C. pilosula var. modesta samples and notably higher than those of C. tangshen samples. Consequently, a rapid, precise, and feasible strategy was established for the discrimination and quality control of CR with different origins.
Bai-Hu-Jia-Ren-Shen-Tang Decoction (BHJRSTD) is one of the oldest classic Chinese medicine prescriptions which used in the field of treatment of diabetes. However, to the best of our knowledge, the ingredients of this prescription have not been identified, and there are very few studies on the anti-diabetic mechanism of this prescription. Therefore, BHJRSTD was detected and identified by ultra-high-performance liquid chromatography coupled with Quadrupole-Exactive Focus Orbitrap MS (UHPLC–Q/Orbitrap/MS/MS). We identified 74 compounds, including flavonoids, alkaloids, chalcones, xanthones, phenols, phenylpropanoids, terpenes, triterpenes, amino acid derivatives, etc. Then, Sprague Dawley rats were fed with a high-fat and high-sugar diet for two months and injected with streptozotocin (STZ) to induce type 2 diabetes (T2DM). The diabetic rats were randomized to given metformin (200 mg kg−1·d−1, n = 15), BHJRSTD extracts (40 g kg−1·d−1) and BHJRSTD extracts (10 g kg−1·d−1) by gavage for 8 weeks. The results confirmed that BHJRSTD significantly decreased the level of MDA and increased levels of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), it shows that the prescription has significant antioxidant activity in the treatment of T2DM.
Flavonoids are the most abundant components in Salvia plebeia, with significant pharmacological antioxidant and hepatoprotective properties. Hispidulin and homoplantaginin are the main flavonoid components in S. Plebeia. In this study, we established an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to determine hispidulin and homoplantaginin in rat plasma samples, which were precipitated using acetonitrile-methanol (9:1, v/v). We used a UPLC HSS T3 (100 mm × 2.1 mm, 1.7 μm diameter) chromatographic column, an acetonitrile-water (containing 0.1% formic acid) mobile phase, and a gradient elution flow rate of 0.4 mL min−1 in an elution time of 4 min. We used electrospray ionization (ESI) detection in positive ion mode, and multiple reaction monitoring mode (MRM) for quantitative analysis: m/z 301 → 286 for hispidulin, m/z 463 → 301 for homoplantaginin, and m/z 465 → 303 for internal standard (IS). In pharmacokinetic studies, 24 rats were orally administered hispidulin and homoplantaginin (5 mg kg−1) and received sublingual intravenous injections (1 mg kg−1) at two different doses, four groups with six rats/group. Differences in hispidulin and homoplantaginin pharmacokinetics in rat plasma were evaluated. The calibration curve showed good linearity in the 0.5–1,000 ng mL−1 range, with r > 0.99. Precision, accuracy, recovery, matrix effects, and stability results all met standard biological sample detection requirements. Our pharmacokinetic studies showed hispidulin bioavailability was much higher than homoplantaginin at 17.8% and 0.1%, respectively.
One of the most effective, rapid, and simple methods reversed-phase high-performance liquid chromatography (RP-HPLC) was used for simultaneous development and validation of Eletriptan hydrobromide (ELE HBR) and Itopride hydrochloride (ITP HCL) in combination. The method was validated based on the regulations of United States Pharmacopeia (USP) and International Conference on Harmonization (ICH) guidelines. Separation of both drugs was achieved within approximately 5 min by using a mobile phase made up of a 70:30 ratio of phosphate buffer and acetonitrile having a flow rate of 1 mL min−1. Furthermore, a comprehensive study was conducted on precision, accuracy, linearity, inter-day, intra-day studies, an assay of formulated films, and stability studies of combined prepared film. Co-efficient of correlation ranged between 0.9993, and 0.9965 for ELE HBR and ITP HCL respectively. The accuracy of the developed method was accurate as drug recoveries in both cases of ITP HCL, and ELE HBR falls between (99.87, 99.96, and 99.84%) to (99.81, 99.12, and 98.44%) respectively having a concentration range of solutions between 10, 30 and 50 μg mL−1 dilution. Films developed by using both drugs in combination were then validated for assay studies, and it was found that substantial results of 99.05%, and 99.87% were found in the case of ITP HCL and ELE HBR respectively. The stability of the solution and mobile phase showed the method's accuracy as the results were 97% for ITP HCL and 99% for ELE HBR. The proposed method developed for simultaneous determination of ITP HCL and ELE HBR was developed and validation and no interaction of any excipient were found.
In this work, a simple and rapid high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method was developed and validated to carry out the simultaneous measurement of busulfan (BU) and phenytoin (PHT) in the plasma of children. In this method, plasma sample could be prepared by one-step protein precipitation using 1 mL of methanol/water (1:1, v/v). After centrifugation (14,500 rpm, 5 min, 4 °C), 10 μL of the supernatant was injected into a Hypersil Gold C18 column (150 × 2.1 mm, 5 μm, Thermo Fisher Scientific) for separation by gradient elution. Quantification was carried out using multiple reactions monitoring (MRM) under positive scan mode. In the method verification, the calibration curves of BU and PHT showed satisfactory linearity (r > 0.99) at the concentration ranging from 0.02 to 20 μg mL−1. The accuracy and precision were tested at four concentration levels (including the LLOQ level) with the relative error (RE) ranging from −0.80% to 11.45% and coefficient of variation (CV) between 0.93% and 7.74%. There was no pronounced matrix effect to interfere with the quantitative analysis. Compared to determine BU and PHT using two individual methods, less pre-treatment process, labor and blood sample volume are required in this proposed method. Finally, this method was successfully applied to the therapeutic drug monitoring of BU and PHT for children underwent hematological stem cell transplantation.
Solasodine, a steroidal alkaloid, is distributed extensively in Solanaceae plants with multiple biological activities such as neuroprotection, antineoplastic and anticonvulsant activities. However, there is little information about the excretion of intact solasodine in vivo. To investigate its excretion, a reliable LC-MS/MS method for quantitation solasodine in rat urine and feces was established and validated. Sample preparation was carried out by liquid-liquid extraction using MTBE as extractant. Moreover, rat urine was preconditioned with BSA, an anti-adsorptive additive, to prevent the nonspecific binding of solasodine to containers and tubes. The method was validated over the range of 4–2000 ng mL−1. The correlation coefficient (r2) were all above 0.999. The intra- and inter-day precision and accuracy were within 16.9% and between −11.0 and 8.9%, respectively. The recovery of solasodine in urine and feces was in the range of 72.5–80.3 and 75.7–80.2%, respectively. IS-normalized matrix factor ranged from 0.94 to 1.12 with RSD% ≤4.02%. This method was successfully applied to the excretion study of solasodine following oral and intravenous administration.
A new pretreatment method termed ultrasound-assisted extraction (UAE) which is combined with solid-phase extraction which is combined with dispersive liquid-liquid microextraction (SPE-DLLME) followed by gas chromatography-flame ionization detector (GC-FID) analysis has been developed for the determination of diazinon in garden parsley as vegetable samples. The analyte was extracted from garden parsley sample using ultrasound-assisted extraction followed by solid-phase extraction followed by dispersive liquid-liquid microextraction. Various parameters that affect the efficiency of the extraction techniques have been optimized. The calibration plot was linear in the range of 5.0–1,000 μg kg−1 with detection limit of 1.0 μg kg−1 for diazinon in garden parsley samples. The results confirm the suitability of the UAE-SPE-DLLME-GC-FID as a sensitive method for the analysis of the targeted analyte in garden parsley samples.
Fuke Yangrong pill, a traditional Chinese patent medicine, with the functions of nourishing qi and blood, soothing liver and relieving depression, regulating menstruation and removing blood stasis, is composed of 16 Chinese medicinal herbs. For quality control purpose, an HPLC method was established for simultaneous quantification of paeoniflorin, hesperidin and ligustilide in Fuke Yangrong pill. With acetonitrile-0.1% formic acid as mobile phase, gradient elution was carried out using Agilent ZORBAX Eclipse Plus C18 column (250 mm × 4.6 mm, 5.0 μm) at 1.0 mL min−1. Detection wavelength was set at 230 nm for paeoniflorin, 280 nm for hesperidin and ligustilide. The temperature was 30 °C. There was a good linearity between the peak area and the concentration of each component to be measured within their linear range (r ≥ 0.9994). The average recoveries were between 98.6% and 102.6% with RSDs no more than 2.93%. This method was validated to be accurate and convenient, which is suitable for the quality control of Fuke Yangrong pill.
In this study, an accurate, simple, economical and precise Reversed-Phase High Pressure Liquid Chromatography (RP-HPLC) method was developed for the simultaneous estimation of Ozenoxacin and Benzoic Acid in a pharmaceutical cream formulation, according to the International Conference on Harmonisation (ICH) guidelines. Chromatographic separation was achieved by gradient elution, on RP-HPLC Instrument, equipped with column C8 (150 mm × 4.6 mm, 5 μm particle size) using Ultra Violet (UV) detector at 235 nm wavelength, by using Mobile Phase A: triethylamine, trifloroacetic acid and water (1:1:1000) and Mobile Phase B: methanol and Diluent: water, acetonitrile and triethylamine (500:500:1), at flow rate 0.8 mL min−1; injection volume of 20 μL; column oven temperature 45 °C and sample temperature: 25 °C; Run time: 15 min. All the validation parameters were within the acceptance criteria, as per ICH requirements, for Ozenoxacin and Benzoic acid. Consequently, this method has found to be validated, simple, rapid and successfully applicable, to the simultaneous estimation of Ozenoxacin and Benzoic acid by RP-HPLC, for routine analytical testing in quality control, with a run time of 15 min and for future research studies. Forced degradation of Ozenoxacin cream 1% w/w formulation was performed and found that validated method has stability indicating potential that needs to be further studied.
Food, water, and energy scarcity threaten India's future, and they must be addressed first. To meet the country's ever-increasing population needs, agricultural productivity must be expanded. For the crop-land suitability, we have studied an area of about 6,539 km2 in Vizianagaram district. The majority of the land is used for paddy agriculture (Kharif). The crop-land suitability has been evaluated based on the different parameters identified in that study area. “Remote sensing (RS)” and “geographic information system (GIS)” were combined for the crop-land suitability using nine parameters. The slope, elevation, rainfall, soil texture, lithology, groundwater, land use–land cover (LULC), TWI, and land surface temperature are the primary criteria used to determine the crop-land suitability in the Vizianagaram district (AP). Thematic maps were created using Landsat 8 images and SRTM DEM images from USGS Earth Explorer. Based on these maps and the influence of these parameters, we may assign weights to the parameters and then rank them, the Analytic Hierarchy Process (AHP) allowing us to identify which area is more suitable for good crop productivity and which is not. In this study, the soils are divided into four categories: low suitability, moderate suitability, high suitability, and extremely high suitability. The suitability index is found to be in the range of 0–55.2%, which indicates the lack of outstanding agricultural lands in the sudy region.
Ivosidenib (AG-120) is an unlisted, but estimated to be valid, oral inhibitor for isocitrate dehydrogenase 1 (IDH1) in the phase Ⅰ study of IDH1-mutated acute myeloid leukemia (AML) patients. This paper presents the investigation and validation of a rapid, effective, qualitative and quantitative determination method of ivosidenib in rat plasma by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The samples were treated using acetonitrile precipitation to remove protein influence. Then, the supernatant was extracted to analyze plasma concentration traits. In the UPLC system, acetonitrile and water containing 0.1% formic acid were selected as a cosolvent mobile phase, applying a gradient elution to isolate compounds in a C18 column. Mass detections were performed on a triple quadruple mass spectrometer in positive ion mode. Electroshock characteristic fragment ionization was used for m/z 583.95→214.53 for ivosidenib for quantitative determination, m/z 583.95→186.6 for qualitative determination, and m/z 492.06→354.55 for IS. The selectivity, linearity, stability, accuracy and precision were verified by reaching the guideline criteria from European Medicine Agency (EMA) and the Food and Drug Administration (FDA). The calibration curve was linear over the concentration range of 2–2,000 ng mL−1 for ivosidenib in rat plasma with a lower limit of quantification (LLOQ) of at least 2 ng mL−1. Additionally, there was no distinct matrix effect or carry-over phenomenon. The method was successfully established and applied to separate ivosidenib from plasma, with the entire analytical process being performed within 3 min for each sample, which shows high-efficiency and convenience for further studies of ivosidenib.
A fast reliable micellar electrokinetic methodology was investigated for the concurrent quantitation of six antimicrobial and anti-inflammatory drugs, namely, ciprofloxacin, dexamethasone, metronidazole, ornidazole, spiramycin and tinidazole. The method has the merits of rapidity, precision, and sensitivity. The separation was carried out in less than 7 min by applying a basic background electrolyte consisting of 25 mM disodium tetraborate buffer, pH 9 containing 50 mM SDS at 25 kV using photodiode array detector at 230 and 315 nm. The internal standard used during analysis was cromolyn sodium and validation was carried out following ICH guidelines. The proposed method showed linear response over the range from 0.5 to 10.0 μg mL−1 reaching limits of detection and limits of quantitation in the ranges of 0.09–0.2 μg mL−1 and 0. 27–0.6 respectively. The method's greenness was estimated using the GAPI tool where excellent greenness was concluded. Co-formulated or single-ingredient commercial preparations were investigated and the results were statistically evaluated.
A simple, rapid, and sensitive method based on UPLC-MS/MS was developed to determine spiraeoside in mouse blood, and was applied to the pharmacokinetics and bioavailability of spiraeoside after mice after intravenous (a dose of 5 mg kg−1) and oral (a dose of 20 mg kg−1) administration. On HSS T3 column set at 40 °C, chromatographic separation was obtained with the mobile phase of acetonitrile and 0.1% formic acid using the gradient elution. Spiraeoside and internal standard (IS) were quantitatively analyzed using multiple reaction monitoring (MRM) mode in electrospray (ESI) positive interface. The MRM mode was monitoring the fragmentation of m/z 465.4→303.1 and m/z 451.3→ 289.2 for spironoside and IS, respectively. The results showed a good linear relationship was in the concentration range of 1–200 ng mL−1 (r > 0.998) and the lower limit of quantification (LLOQ) was 1.0 ng mL−1. The intra- and the inter-day precision (RSD%) of the method was within 14.0%, and the accuracy ranged from 90.0% to 115.0%. The extraction recovery of spriaeoside was better than 63.0%, and the matrix effects were in the range of 86%–98%. It also showed the half-life was short, and the absolute bioavailability was 4.0% in mice. Therefore, the established UPLC-MS/MS method was suitable for the pharmacokinetic and bioavailability study of spiraeoside in mice.
In this study, we propose a simple, cost-effective, and sensitive high-performance liquid chromatography with both detection techniques such as diode-array detection and fluorescence detection (HPLC-DAD-FLD) for the determination of nesfatin-1 in fetal bovine serum samples. The limit of detection (LOD) and limit of quantification (LOQ) for nesfatin-1 were set at satisfactory values in the range 0.22–0.35 mg mL−1 and in the range 0.67–1.05 mg mL−1, respectively (at two different wavelengths (DAD) and at four different wavelengths (FLD)). Analyte concentrations were determined as the average value from fetal bovine serum matrix samples. The preliminary results show that the SPE procedure on Isolute Si-TsOH (SCX-3) could be used for further nesfatin-1 analyses in human serum samples. Both the SPE technique, chromatographic analysis with gradient elution mode and detection technique are fast and convenient.
In this scientific paper, thermochemical conversion of redwood (RW) was studied. Using the thermogravimetric analysis' technique (TGA), the thermal behavior of RW samples was examined at four heating rates ranging from 5 to 20 K min−1 in inert atmosphere between 300 and 900 K. Two main objectives have been set for this study; the first one was the determination of the kinetic decomposition parameters of RW (Pinus sylvestris L.), and the second one was the study of the variation of characteristic parameters from the TG-DTG curves of the main RW's components, such as; cellulose, hemicellulose and lignin. The kinetic analysis was performed using three isoconversional methods (Vyazovkin (VYA), Friedman (FR) and Flynn-Wall-Ozawa (FWO)), Avrami theory method and the Integral master-plots (Z(x)/Z(0.5)) method to estimate activation energy (Ea), reaction order (n), pre-exponential factor (A) and model kinetic (f(x)) for the thermal decomposition of cellulose, hemicellulose and lignin components.
The DTG and TG curves showed that three stages identify the thermal decomposition of RW, the first stage corresponds to the decomposition of hemicellulose and the second stage corresponds to the cellulose, while the third stage corresponds to the lignin's decomposition. For the range of conversion degree (x) investigated (0.1 ≤ x ≤ 0.7), the mean values of apparent activation energies for RW biomass were 127.60–130.65 KJ mol−1, 173.74–176.48 KJ mol−1 and 197.21–200.36 KJ mol−1 for hemicellulose, cellulose and lignin, respectively. Through varied temperatures from 550 to 600 K for hemicellulose, from 600 to 650 K for cellulose and from 750 to 800 K for lignin, the corresponding mean values of reaction order (n) were 0.200 for hemicellulose, 0.209 for cellulose and 0.047 for lignin. The pre-exponential factor's average values for three components of RW ranges from 0.08 × 1012 s−1 to 2.5 × 1012 s−1 (Ahemicellulose = 1.09 × 1012 s−1), 0.10 × 1014 s−1 to 0.28 × 1014 s−1 (Acellulose = 0.17 × 1014 s−1) and 3.07 × 1016 s−1 to 3.69 × 1016 s−1 (Alignin = 3.33 × 1016 s−1), respectively. The experimental data of RW had overlapped the D4, D2 and F3 in the conversion degree of 10–30%, 30–55% and 55–70% for the three components, respectively.
A new method for the analysis of four target flavonoids in two kinds of citrus samples by ultra-high performance supercritical fluid chromatography (UHPSFC) method was developed. Main variables affecting the UHPSFC separation were optimized, and under the optimized conditions the four target compounds (tangeretin, nobiletin, hesperetin and naringenin) can be separated within 10 min. The UHPSFC method allowed the determination of the four target compounds in the diluted stock solutions with limit of detection (LOD) ranging from 1.08 to 2.28 μg mL−1, and limit of quantification (LOQ) ranging from 1.45 to 4.52 μg mL−1, respectively. The coefficients of determination (R2) of the calibration curves were higher than 0.9950. The recoveries of the four target compounds at three different concentrations were in the range of 82.4–117.6%. The validation results demonstrated that the proposed method is simple, accurate, time-saving and environment friendly, and it is applicable to a variety of complex samples such as medicine-food dual purpose herbs and functional foods.
To overcome the problems of seasonality and geographical location in fruit production and processing, the production of aseptic semi-finished juice is an excellent solution. Even without refrigeration, aseptic pressing has a shelf life of more than a year, making it possible to produce finished products all year round. The production technology involves the addition of ascorbic acid to the pulp to fix or preserve colour. There is an increasing customer demand for ascorbic acid substitutes on the international market. In Hungary, one of the most important exports is aseptic sour cherry juice. In our work, ascorbic acid used for colour fixation was replaced by acerola concentrate. The anthocyanin content and colour coordinate values (L*, a*, b*, H, C) of aseptically filled sour cherry juice were determined and compared with the control sample during the 12 months of storage.
Ziprasidone is the second generation antipsychotic drug with unique multipotent G-protein-coupled (GPCR) receptor binding profile. Since ziprasidone is a highly lipophilic and unstable compound, development of efficient method for a concurrent assay of ziprasidone and its main impurities was a very challenging task.
The UHPLC-MS/MS method that we developed for simultaneous determination of ziprasidone and its main impurities (BITP, Chloroethyl-chloroindolinone, Zip-oxide, Zip-dimer, and Zip-BIT) was compared with some other related HPLC-UV methods of our own and other authorship. An increase of the mobile phase pH value from 2.5 to 4.7 units in the examined analytical methods influenced elution order of the investigated compounds. It was found out that the UHPLC-MS/MS method is more selective and sensitive than the earlier developed HPLC-UV method. Similar to our earlier HPLC-UV method, the UHPLC-MS/MS method is linear with a correlation coefficient (r) above 0.99 for all the analysed compounds, but with a negligibly lower precision and accuracy. Finally, with shorter analysis time, smaller column size and reduction of solvent consumption, UHPLC-MS/MS is assumed as a greener method than HPLC-UV for the ziprasidone purity assay.
After transfer of the UHPLC-MS/MS method to the UHPLC-DAD system, suitability of the UHPLC-DAD method for routine control of ziprasidone and its main impurities is examined and confirmed based on the retained good selectivity, resolution and short analysis time.
As a means of assisting the selection of promising soil classification systems, a set of criteria were presented and tested. Inside the studied slightly saline plot World Reference Base (WRB) and Hungarian soil classification (HU) were compared at all four levels in terms of class separability, correlation to biomass, parsimony and homogeneity of classes. WRB surpassed HU in terms of the very important homogeneity of classes only, but HU performed better in terms of class separability, correlation to biomass and parsimony of classes. With many possible classification units WRB categorized the soil into a large number of classes, but 67% and 78% of them were single-profile classes at levels 3 and 4, respectively inside the ca 0.9 km2 area.
Wild edible plants (WEPs) can be widely found in the world and defined as native species that grow naturally in their natural habitat. They have become part of the traditional food as human diet and used in folk medicine to treat diseases. They are very rich in terms of nutraceuticals. Melatonin is a natural hormone providing several benefits for human health. It has functions such as regulating growth and development and increasing tolerance to environmental stress factors in plants. It is stated that the serum melatonin level in humans increases after intake of foods containing melatonin. This study examined the presence of melatonin in wild grown cornelian cherry fruits by UFLC-FD and determined suitable extraction and chromatographic conditions. The optimum mobile phase, excitation/emission wavelength, and extraction solvent were determined as methanol: water: acetic acid, 275/345 nm, and methanol: water: HCl, respectively. Melatonin content in fruits ranged from 130.82 to 201.84 ng g−1 in fresh fruit.
A review of the international literature also found that the amount and the presence in slurry of oestrus inducer hormone preparations used in intensive dairy cattle production has not been investigated. In our study, we followed the path of 5 different sex-inducing drugs (alfaglandin, PGF, dinolytic, gonavet, ovarelin) including three active pharmaceutical ingredients (D-Phe6-Gonadorelin, Kloprostenol and Dinoprost-tromethamine) used in a cattle farm in Pest County from their use until their appearance in the slurry from 2017 to 2020. The study included a review of drug consumption and a seasonal analysis of the hormonal effects of slurry produced on the farm in quarterly cycles each year. We also tested separately the hormonal effects of the hormone preparations used on the farm. For the estrogenic effect tests, the yeast test with the human estrogenic receptor was used according to ISO 19040. Statistical evaluation of the results (Pearson correlation and Principal Component Analysis) was used to identify relationships between the use of sex inducers, the reproductive biology of the colony and the estrogenic effect of the slurry. We found that the estrogenic effects of slurry and sludge are strongly correlated. All three pharmaceuticals tested showed a strong correlation with the estrogenic effect of slurry/sludge. Our investigations confirm that slurry among other reasons due to its hormone and drug content shall be considered as a material that needs to be disposed of by new treatment methods before application to the field, because of its environmental and health risks.
The analysis of phenolic acids (PAs) is of great importance, because they are frequently present in natural products and their derivatives, and these compounds also have multiple beneficial effects to human health. This work is focusing on the separation of seven PAs (caffeic acid, coumaric acid, gallic acid, ferulic acid, protocatechuic acid, sinapic acid, and syringic acid), in a reversed-phase liquid chromatographic (RP-HPLC) isocratic method using a hydrophilic deep eutectic solvent (DES) as a mobile phase additive. The analysis was carried out with a diode array detector. The used DES was composed by choline chloride and glycerol, and it was characterized by infrared spectroscopy. The combination of choline chloride:glycerol (1:4) added at 0.25% to mobile phase composed of 0.15% formic acid aqueous solution and methanol (80:20), showed the best separation for target analytes. The new proposed method was validated, and results indicated that the proposed method is linear, selective for almost all analytes, provided high sensitivity with limit of detection ranges from 0.009 to 0.023 mg mL−1, and has satisfactory precision and accuracy, with values of relative standard deviation of 0.24–2.65% and recoveries of 97.97–109%, respectively. Additionally, this method was successfully applied to simultaneous determination of phenolic acids in three kinds of samples of powder to prepare lemon flavour drink enriched with black tea extract.