Authors:Vladimir Dobričić, Jelena Bošković, Dragana Vukadinović, Sote Vladimirov, and Olivera Čudina
Eight 17β-carboxamide glucocorticoids with local anti-inflammatory activity were selected and their retention behavior tested in six RP-HPLC systems (I–VI). logkw, a, and φ0 parameters were calculated and correlation with previously determined logPo/w values was examined. RP-HPLC system IV, which consisted of cyano column and methanol–water mobile phases (50:50, 60:40, 70:30, and 80:20, v/v), was selected as the most reliable for lipophilicity prediction and used for the analysis of chromatographic behavior of remaining fourteen 17β-carboxamide glucocorticoids. Quantitative structure-retention relationships analysis was performed and PLS(logkw) model was selected as the most statistically significant. On the basis of selected model and interpretation of corresponding descriptors, new derivatives with higher logkw values and higher expected lipophilicity were designed.
Authors:Tsedekech Gebremeskel Weldmichael, Erika Michéli, and Barbara Simon
Land use change may modify key soil attributes, influencing the capacity of soil to maintain ecological functions. Understanding the effects of land use types (LUTs) on soil properties is, therefore, crucial for the sustainable utilization of soil resources. This study aims to investigate the impact of LUT on primary soil properties. Composite soil samples from eight sampling points per LUT (forest, grassland, and arable land) were taken from the top 25 cm of the soil in October 2019. The following soil physicochemical parameters were investigated according to standard protocols: soil organic matter (SOM), pH, soil moisture, NH4+–N, NO3––N, AL-K2O, AL-P2O5, CaCO3, E4/E6, cation exchange capacity (CEC), base saturation (BS), and exchangeable bases (Ca2+, Mg2+, K+, and Na+). Furthermore, soil microbial respiration (SMR) was determined based on basal respiration method. The results indicated that most of the investigated soil properties showed significant difference across LUTs, among which NO3––N, total N, and K2O were profoundly affected by LUT (p ≤ 0.001). On the other hand, CEC, soil moisture, and Na+ did not greatly change among the LUTs (p ≥ 0.05). Arable soils showed the lowest SOM content and available nitrogen but the highest content of P2O5 and CaCO3. SMR was considerably higher in grassland compared to arable land and forest, respectively. The study found a positive correlation between soil moisture (r = 0.67; p < 0.01), Mg2+ (r = 0.61; p < 0.01), and K2O (r = 0.58; p < 0.05) with SMR. Overall, the study highlighted that agricultural practices in the study area induced SOM and available nitrogen reduction. Grassland soils were more favorable for microbial activity.
Authors:Gulab Khan Rohela, Prasad Bylla, Sreenu Pendli, Rajender Korra, Rajender Gandu, and Christopher Reuben
Rauwolfia tetraphylla L., is an important medicinal plant in Apocynaceae family and is recognized as an alternative source to Rauwolfia serpentina L., in terms of anti-hypertensive alkaloid production i.e. reserpine. In view of this, the present study is conducted to estimate the reserpine content in different parts (leaf, stem and root) of field grown plants (2 years old), tissue cultured plantlets (R1) (two months old) and cell suspensions cultures (two months old with and without precursor feeding) of R. tetraphylla by using high performance liquid chromatography (HPLC) technique. Overall maximum content of reserpine (in %) was estimated from the root samples. Roots of field grown plants has recorded high percent of reserpine (0.39%) followed by roots of tissue cultured plantlets (0.35%) and root callus based cell suspension cultures (0.38 %) which was fed with precursor amino acid (100 mg/L of tryptophan). In control type of root callus based cell suspension cultures, reserpine content was quantified as 0.14%; by precursor feeding (100 mg/L of tryptophan) it was enhanced to 0.38%. In conclusion, the reserpine content (0.35 and 0.38%) produced by the roots of tissue cultured plantlets (R1) and 100 mg/L tryptophan fed root callus based cell suspensions was comparable to that of the reserpine content (0.39%) of root parts of field grown plants. The present study demonstrates the reserpine production by in vitro cell suspension cultures throughout the year without sacrificing the medicinal plants.
Authors:Steven Yeung, Quanlan Chen, Yongbang Yu, Bingsen Zhou, Wei Wu, Xia Li, Ying Huang, and Zhijun Wang
Ganoderma lucidum (GL), also known as Reishi or Lingzhi, is a medicinal mushroom widely used in traditional and folk medicines. The extracts made from the fruiting body and spore of naturally grown GL are the most frequently used in commercial products. More than 400 compounds have been identified in GL with the triterpenoids considered to be the major active components. Large variations in the chemical components were reported in previous studies and there is no comprehensive study of the content of multiple major triterpenoids in the GL product. In addition, there is no report in the comparison of chemical profiles in different parts of GL (i.e., fruiting body and spore). Determining the chemical composition and comparing the differences between fruiting body and spore are essential for the identity, efficacy and safety of various GL products.
In this study, 13 compounds (ganoderenic Acid C, ganoderic Acid C2, ganoderic Acid G, ganoderic Acid B, ganoderenic Acid B, ganoderic Acid A, ganoderic Acid H, ganoderenic Acid D, ganoderic Acid D, ganoderic Acid F, ganoderic Acid DM, ganoderol A, and ergosterol) were selected as the chemical markers. The purpose of this study is to develop an HPLC-DAD fingerprint method for quantification of these active components in GL (spore and fruiting body) and test the feasibility of using the HPLC-DAD fingerprint for quality control or identity determination of GL products.
The results showed that this method could determine the levels of the major components accurately and precisely. Among the 13 components, 11 ganoderma acids were identified to be proper chemical markers for quality control of GL products, while ganoderal A was in a very low amount and ergosterol was not a specific marker in GL. The extracts of fruiting body contained more chemical compounds than those of spore, indicating that these 11 compounds could be a better chemical marker for the fruiting body than the spore. The HPLC chemical fingerprint analysis showed higher variability in the quality of GL harvest in different years, while lesser variation in batches harvested in the same year.
In conclusion, an HPLC assay detecting 11 major active components and a fingerprinting method was successfully established and validated to be feasible for quality control of most commercial GL products.
Authors:Ke Ren, Tiantian Feng, Hai Shi, Jianshe Ma, and Yongxi Jin
Narciclasine is a 7-hydroxy derivative of lycorisidine. It was the first alkaloid isolated from the stem of narcissus (Amaryllidaceae) in 1967. Six mice were given narciclasine (5 mg/kg) by intravenous administration. A UPLC-MS/MS method was developed to determine narciclasine in mouse blood. Tectorigenin (internal standard, IS) and narciclasine were gradient eluted by mobile phase of methanol and 0.1% formic acid in a BEH C18 column. The multiple reaction monitoring (MRM) of m/z 308.1→248.1 for narciclasine and m/z 301.1→286.0 for IS with an electrospray ionization (ESI) source was used for quantitative determination. The calibration curve ranged from 1 to 6,000 ng/mL. The accuracy was from 92.5 to 107.3%, and the matrix effect was between 103.6 and 107.4%. The developed UPLC-MS/MS method was successfully applicated to a pharmacokinetic study of narciclasine in mice after intravenous administration (5 mg/kg).
Authors:Jovana Tomić, Nevena Djajić, Danica Agbaba, Biljana Otašević, Andjelija Malenović, and Ana Protić
This paper is aimed at developing a gradient elution reversed-phase high-performance liquid chromatography (RP-HPLC) method for the separation of a complex mixture composed of ivabradine and its eleven impurities, in a reasonable timeframe. In order to obtain a robust and reliable HPLC method for separation of this mixture, Analytical Quality by Design (AQbD) was applied. This approach demonstrated to be useful in development of a long lasting life cycle methods. Four chromatographic variables were defined as key method parameters (KMPs) and optimized towards the analytical target profile (ATP). Designated KMPs were initial and final amount of acetonitrile in the mobile phase, pH value of the aqueous phase and gradient time, while resolutions of critical peak pairs were denoted as critical method attributes (CMAs). Relationships between KMPs and CMAs were obtained with the aid of Design of Experiments (DoEs) methodology among which Box-Behnken design (BBD) was employed to gain valid mathematical models. Obtained mathematical equations were used to construct the Design Space (DS) and select reliable optimal separation conditions. They included 11% (v/v) and 34% (v/v) of initial and final amount of acetonitrile, respectively, as well as 45 min of gradient elution time and 20 mM ammonium acetate as aqueous mobile phase with pH set to 7.35. The possibility to separate the diastereoisomers of impurity X was also evaluated. It was demonstrated that this separation could not be achieved in gradient elution mode within the defined variable domains and in a reasonable time span. The developed method was validated according to ICH Q2 (R1) guideline and met all the required criteria.
Authors:Jianwei Han, Wenbo Zhu, Ling Yu, Yajun Chen, Gaosong Wu, and Zhibin Wang
A rapid, sensitive and convenient method based on ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was developed and validated for the simultaneous quantification of calycosin-7-O-β-d-glucoside (CCSG), ononin, calycosin, (6aR,11aR)-9,10-dimethoxypterocarpan-3-O-β-d-glucopyanoside (DPPG), and 7,2′-dihydroxy-3′,4′-dimethoxyisoflavan-7-O-β-d-glucopyanoside (DIFG) in rat plasma after oral administration of the methanol extraction from Radix Astragali. Theophylline played the role of internal standard (IS). Preparation of plasma samples by liquid-liquid extraction method with ethyl acetate after precipitation of protein with methanol. The analytes were detected with a triple quadrupole tandem mass spectrometery (MS) in multiple reaction monitoring (MRM) mode and a positive ion electrospray ionization (ESI). The method was validated with the concentration ranges of 1.96–62.69 ng/mL for CCSG, 1.70–54.5 ng/mL for ononin, 1.85–59.06 ng/mL for calycosin, 2.14–137.24 ng/mL for DPPG and1.96–125.25 ng/mL for DIFG, respectively. The method had the lower limit of quantification (LLOQ) with 0.49, 0.21, 0.92, 1.07, and 0.98 ng/mL for CCSG, ononin, calycosin, DPPG and DIFG respectively, and the precision less than 10%. The RSD of the accuracy was in the range of −4.35–8.91%. The results may be helpful to provide more accurate references to clinical application of this herb.
Authors:Jing Zhou, Hongzhe Wang, Caiyun Miao, Yunxi Yao, and Jianshe Ma
A rapid and simple UPLC-MS/MS method was developed to determine toddalolactone in mouse blood and applied to measure the pharmacokinetics of toddalolactone in mice. Blood samples were first preprocessed by ethyl acetate liquid-liquid extraction. Oxypeucedanin hydrate (internal standard, IS) and toddalolactone were gradient eluted from a UPLC BEH C18 column using a mobile phase consisting of acetonitrile and water (0.1% formic acid). Using electrospray ionization (ESI) as the ionization source, multiple reaction monitoring was used to detect the precursor and product ions of m/z 309.2 and 205.2, respectively, for toddalolactone and of m/z 305.1 and 203.0 for IS, respectively, for quantitative detection. A calibration curve was run over the concentration range of 5–4,000 ng/mL (r > 0.995). The matrix effects ranged from 93.5 to 98.4%, and the recovery was higher than 77.3%. The precision was less than 13%, and the accuracy ranged from 90.9 to 108.4%. The developed UPLC-MS/MS method was successfully used for measuring the pharmacokinetics of toddalolactone in mice after oral (20 mg/kg) and intravenous administration (5 mg/kg), and the absolute bioavailability of toddalolactone was 22.4%.
Authors:Min Zhang, Zhenling Zhu, Mengyue Wang, Jincai Hou, Yinqing Li, and Xiaobo Li
Bao-Yuan Decoction (BYD), a widely used traditional Chinese medicine formula, is worth developing into modern dosage forms. To assess the quality of traditional decoction, the commonly used ultra-performance liquid chromatography coupled with diode array and evaporative light scattering detection (UPLC-DAD/ELSD) method was initially applied to develop the analytical methods for the qualitative fingerprints and simultaneous quantitation of multiple marker compounds in BYD. Based on 16 batches of BYD prepared from multiple batches of qualified crude herbs combined randomly, the characteristic fingerprints were generated, with 41 and 19 common peaks detected by DAD and ELSD, respectively. Furthermore, ginsenosides Re, Rg1 and Rb1, calycosin-7-glucoside, calycosin, liquiritin, isoliquiritin apioside, isoliquiritin, glycyrrhizic acid and cinnamic acid were qualified as marker compounds to represent the herbs composing the formula. The characteristic fingerprints and the content ranges of multiple batches of the decoction were obtained, thus providing guidance for the quality control of modern dosage forms. The combination of these qualitative and quantitative methods will be an effective operational measure by which to evaluate and control the quality of BYD from traditional decoction to modern dosage forms.