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Koncepcióváltás a belvízgazdálkodásban: talajtani és vízminőségi kérdések

Conceptual Change in Excess Water Management: Soil and Water Quality Issues

Agrokémia és Talajtan
Authors:
Benjámin Pálffy
,
István Fekete
, and
Károly Barta

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.

Open access

Abstract

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.

Open access

Abstract

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.

Open access

Abstract

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.

Open access
Acta Chromatographica
Authors:
Waqar Siddique
,
Rai Muhammad Sarfraz
,
Muhammad Zaman
,
Riffat Khan
,
Maria Gul
,
Farhan Asghar
,
Tangina Malik
,
Asiya Saif
,
Qurat-Ul-Ain Shamim
,
Ahmad Salawi
,
Meshal Alshamrani
,
Yosif Almoshari
, and
Fahad Y. Sabei

Abstract

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.

Open access

Abstract

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.

Open access
Acta Chromatographica
Authors:
Tiantian Lu
,
Xiaohong Wang
,
Qi Zhang
,
Kun Liu
,
Tongxin Xu
,
Quande Wang
,
Pengfei Zhao
, and
Zhongzhe Cheng

Abstract

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 (r 2) 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.

Open access

Abstract

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.

Open access