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Simultaneous determination of seven sesquiterpene lactone glucosides in Ixeris dentata by high-performance liquid chromatography coupled with tandem mass spectrometry and their antiviral activities
Authors: SeonJu Park, Nanyoung Kim, Jun Hyung Park, Sang-Won Lee, Jae-Hyoung Song, Hyun-Jeong Ko, Han-Jung Chae, Hyung-Ryong Kim and Seung Hyun Kim

Ixeris dentata (Thunb. ex Thunb.) Nakai (Asteraceae), a well-known edible vegetable in Asia, contains various bioactive secondary metabolites, including sesquiterpene lactones. In this study, a high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) method has been developed and validated for simultaneous determination of seven sesquiterpene lactone glucosides isolated from the roots of I. dentata. In addition, these compounds were evaluated in terms of their antiviral activities against coxsackievirus B3 (CVB3) and human enterovirus 71 (EV71). The developed method was validated in terms of linearity (R 2 > 0.9996), precision (RSD < 2.24%), accuracy (96.30–102.77%), and stability (RSD < 1.94%) and successfully applied to the quantitation of the I. dentata root samples collected from six different regions of Korea. The content of sesquiterpene lactone glucosides varied significantly based on the region. For the antiviral activities, guaianolides with an ester group at C-8 (compounds 6 and 7) showed the most potent activities against CBV3, while germacranolide (compound 5) showed the most consistent antiviral activity against both CVB3 and EV71. The method was validated to be simple and reliable to simultaneously determine seven putative bioactive sesquiterpene lactone glucosides, the substantial chemotaxonomic markers, in I. dentata root samples.

Open access
The soil conditions of the forests of Zala County and their impact on the growth of beech
Authors: András Bidló, Adrienn Horváth and Gábor Veperdi

Summary

During the research, we studied the soil conditions in Zala County's forests and examined the effect on the growth of beech forests on these conditions. Data of National Forest Data Base (NFDB) were analysed for investigation. Most of the forests in Zala County are situated less than 150 m above sea level, their location and topography is very diverse. In most of the forests the groundwater level is deeply beneath the surface so the forests can utilize only the amount of precipitation. In accordance with the geological and climatic conditions, Luvisols were formed predominantly, especially the clayic Luvisols and the gleyic Luvisols are the most typical. In addition, there are still Cambisols and stagnic Luvisols as well. In a small percentage, there are forest stands on rendzinic Leptosols, Vertisol, Regosol and Histosol. According to the favourable parent material, forests have got a deep or medium thickness of soil and the typical texture is loam. Based on the research, soil layer thickness and texture had significant impact on the growth of beech forest stands in terms of soil properties.

Open access
Substantiation of Parameters and Operating Modes for the Bunch Planting Device of the Pneumatic Seeder
Authors: Ivan A. Kravchenko, Ivan N. Krasnov, Aleksandr A. Potseluev and Vladimir D. Sidorov

Abstract

The purpose of this work is to develop a dosing system that provides high-quality bunch planting of watermelon seeds with a given seeding rate and their uniform distribution over the plant nutrition area. It is important to know how many seeds it is needed in the bunch in order to provide the required number of plants in a certain plant nutrition area. The method to achieve this goal is to determine the optimal operating modes for the seeding device, in which the dosing system would supply the seed to the bunch without gaps, searching for dependencies that can determine the required number of the sown seeds in the bunch, taking into account their germination and the number of plants specified by agrotechnical conditions in every bunch. Based on the obtained dependencies, determining the probability of bunches with various numbers of plants, while sowing four seeds in the seedbed with maximum field germination, the design of experimental seed discs is proposed, allowing bunch planting and germination due to easy destruction of the soil crust. At the same time, optimal use of the nutritional area for plants, and, consequently, an increase in the yield of the sown crops is ensured. Experimental seed discs with a group arrangement of suction holes (four cells each) will provide bunch planting of watermelon seeds in accordance with agrotechnical requirements.

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A talaj ásványi-, valamint repce és napraforgó növényi maradványok nitrogéntartalmának összefüggése jellegzetes hazai talajokon
Authors: József Zsembeli, Marianna Takács, Györgyi Kovács and Géza Tuba

Összefoglalás

Kutatómunkánk elsődleges célja a repce és napraforgó tarlómaradvány N-tartalmának Magyarországra jellemző reprezentatív értékeinek meghatározása volt az országos statisztikai termésadatok és a növényminták N-tartalmának laboratóriumi mérése alapján. Továbbá összefüggést kerestünk a talaj és a növény N-tartalma között.

Vizsgálataink során egész Magyarországot reprezentáló mintavételt végeztünk repce és napraforgó állományokból, 126 növény- és mintegy 70 talajmintát gyűjtöttünk be, melyek N-tartalmát laboratóriumban határoztuk meg.

Kiszámoltuk a két növény országos termésátlagával keletkező tarlómaradvány mennyiségét és a mért N-tartalom értékek alapján megbecsültük a tarlómaradványok N-tartalmát. Összefüggést mutattunk ki a talaj és a növény N-tartalma között. Esettanulmány jeleggel kiszámítottuk egy olyan terület N-mérlegét, amelyre vonatkozóan rendelkezésre áltak a számításhoz szükséges adatok.

Eredményeink legfőbb gyakorlati vonatkozása, hogy a növényi maradványok felszecskázása és talajba dolgozása útján visszapótolt N mennyiségének meghatározása hosszabb távon hozzájárulhat a növénytáplálás költségeinek csökkentéséhez, illetve a természeti erőforrásokkal való takarékosabb gazdálkodáshoz.

Open access
Talajok agyagtartalmának becslése gamma-spektroszkópiai mérésekkel
Authors: Ramóna Matula and Tibor Tóth
Open access
Thin-Layer Chromatographic Enantioresolution of (RS)-Ketorolac Using L-Amino Acids as Chiral Additive in Stationary Phase
Authors: Manisha Singh and Ravi Bhushan

Summary

Direct resolution of enantiomers of (RS)-ketorolac was achieved by thin-layer chromatography on silica gel plates using enantiomerically pure L-tryptophan, L-valine, L-methionine, and L-histidine as chiral additive in the stationary phase. The solvent system (acetonitrile, methanol water, and chloroform) with different ratios was successful in resolving the enantiomers. Spots were detected by use of iodine vapor. The detection limit was 0.4 µg mL−1 for each enantiomer of (RS)-ketorolac. The native enantiomers were isolated and characterized.

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Transfer of seven thin-layer chromatography (TLC) Global Pharma Health Fund E.V. Minilab protocols for screening counterfeit pharmaceutical products in the field to quantitative high-performance TLC (HPTLC)–densitometry methods was performed using a model process published previously. The developed and validated methods for tablets containing amlodipine besylate, cefpodoxime proxetil, cetirizine 2HCl, diclofenac sodium, efavirenz, mefenamic acid, and atovaquone + proguanil HCl involved the use of only relatively inexpensive and nontoxic solvents, Merck KGaA Premium Purity HPTLC silica gel 60 F254 plates, semi-automated sample and standard solution application with a CAMAG Linomat 4, and automated densitometry with a CAMAG Scanner 3 for detection, identification, and quantification. In addition, previously transferred HPTLC–densitometry methods for azithromycin and for cephalexin were used to analyze a new product of each drug to demonstrate the applicability of the methods.

Open access
Two-Stage Anaerobic Co-digestion of Landfill Leachate and Starch Wastes Using Anaerobic Biofilm Reactor for Methane Production
Authors: Darwin, Ulfa Triovanta and Ridho Rinaldi

Abstract

The study aims to evaluate two-stage anaerobic co-digestion of leachate and starch waste using anaerobic biofilm bioreactor to enhance methane production. The anaerobic digestion process was operated under the mesophilic condition at 35 ± 1 °C. Hydraulic retention time (HRT) applied to the acidogenesis and methanogenesis reactors were 5 and 25 days, respectively. The organic loading rate (OLR) used in the process of acidogenesis was 2.91 gram volatile solid /L.day, while methanogenesis was 0.58 gram volatile solid (VS) per liter per day. Results showed that two-stage process using biofilm was an effective method for operating anaerobic co-digestion of starch waste and landfill leachate in which the system produced higher methane yield at 125.11 mL methane (CH4) per gram volatile solid (VS) added (mL.CH4/g.VS.added) in comparison to the single-stage process (20.57 mL CH4/g.VS.added) and two-stage process (77.60 mL CH4/g.VS.added) without using biofilm. Two-stage process using biofilm also effectively reduced organic matters in the culture in which the system reached 61% BOD removal in comparison to the single-stage process and two-stage process without biofilm that only had 27.6 and 39.3% BOD removal, respectively. This study suggested that the two-stage process using biofilm would be the preferred technique for treating starch waste and landfill leachate.

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Summary

The merits of chemometrics in categorizing different Egyptian olive chemovarieties based on their compositional integrity were implemented in this study. Fingerprints of 9 different olive leaves varieties cultivated in Egypt were established using reversed-phase high-performance thin-layer chromatography (RP-HPTLC) prior to and after post-chromatographic derivatization with natural product-polyethylene glycol (NP/PEG) reagent and image analysis using ImageJ® software in order to build 2 separate data matrices. The chromatographic fingerprints were separately subjected to unsupervised pattern recognition multivariate analysis to build 2 separate models using principal component analysis (PCA) and hierarchical clustering analysis (HCA) algorithms to explore the distribution pattern of different chemovarieties. The second model which involved olive samples’ fingerprints after post-chromatographic derivatization exhibited greater ability to reveal a broader spectrum of phytoconstituents with enhanced sensitivity. Densitometric RP-HPTLC quantification of oleuropein marker was compared to image analysis approach using Sorbfil TLC Videodensitometer® by newly developed and validated methods. Densitometry exhibited better performance characteristics than image analysis method and therefore was executed for determination of oleuropein concentration in the 9 Egyptian olive varieties. Oleuropein marker solely was found to be inadequate for standardization of olive leaves varieties. This study demonstrated a comprehensive approach for the rapid classification of different Egyptian olive varieties, which is crucial to warranting their chemical-consistency and, thereafter, effective consistency.

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Water footprint of yield protein content of twelve field crop species on a Hungarian crop site
Authors: Adnan Eser, Hajnalka Kató, Laura Kempf and Márton Jolánkai

Abstract

Water availability is one of the major physiological factors influencing plant growth and development. An assessment study has been done at the Szent István University, Gödöllő to evaluate and identify the water footprint of protein yield of field crop species. Twelve field crop species (Sugar beet Beta vulgaris, spring and winter barley Hordeum vulgare, winter wheat Triticum aestivum, maize Zea mays, sunflower Helianthus annuus, peas Pisum sativum, potato Solanum tuberosum, alfalfa Medicago sativa, oilseed rape Brassica napus, rye Secale cereale and oats Avena sativa) were involved in the study. Evapotranspiration patterns of the crops studied have been identified by the regular agroclimatology methodology and physiologically reliable protein ranges within crop yields were evaluated.

The results obtained suggest, that water footprint of cereals proved to be the lowest, however maize values were highly affected by the high variability of protein yield. Oilseed crops had considerably high protein yield with medium water efficiency. Alfalfa, potato and sugar beet water footprints were in accordance with their evapotranspiration patterns.

Protein based water footprint assessment seems to be more applicable in crop species evaluations than that of yield based methodologies.

Open access