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Ink classification is the ability to distinguish unknown inks into different groups, and ink source prediction is the ability to predict the manufacturer or model of an unknown ink. These are regular tasks in forensic analysis. The latter is more challenging than the former, as ink source prediction has expanded beyond ink classification. In this work, we reported on an approach to predict the source of black inks based on direct analysis in real time mass spectrometry and assess the strength of black ink source prediction conclusion via the likelihood ratio, using a dataset that included 39 inks from three manufacturers with a high market share. Most of these inks contain similar or identical chemical components. Dimensionality reduction based on the principal component analysis and unified manifold approximation and projection algorithms was implemented, and subsequently, the distribution plots illustrated the variations between and within the inks. Unified manifold approximation and projection showed significant priority in avoiding overcrowding of cluster representation versus principal component analysis, with results as high as 99.83% for the prediction of the ink source using 41,432 spectra data (70% data for training and 30% data for testing) after dimensionality reduction. A likelihood ratio was used to evaluate the strength of ink evidence, and the pool‐adjacent‐violators algorithm and logistic algorithms were used to calibrate the likelihood ratio. The results showed that the pool‐adjacent‐violators algorithm and logistic algorithms both had an excellent equal error rate of 0.004 but slightly different results in the rates of misleading evidence in favor of the prosecutor's hypothesis, rates of misleading evidence in favor of the defense's hypothesis, log likelihood ratio costs after calibration (Cllrcal), and minimum log likelihood ratio costs (Cllrmin). A blind test validated the robustness of the methods. Ink source prediction of 39 black inks based on DART‐MS method with results as high as 99.83% assessed the strength of prediction via likelihood ratio with EER = 0.004. [ABSTRACT FROM AUTHOR]

Four previously undescribed iridoid glycosides, including two bis-iridoid glycosides, and three undescribed lignans, together with 16 known analogues, were isolated from the fruits of Gardenia jasminoides Eills. Their structures were elucidated on basis of spectroscopic methods, and the absolute configurations of three of the unknown compounds were determined by interpretation of their electronic circular dichroic (ECD) and [α] 20 D data. The α -glucosidase inhibitory effects of the isolated compounds were evaluated and all the compounds exhibited slightly inhibitory activity with the values of IC 50 greater than 50 μ M. Seven undescribed compounds, including four iridoid glycosides and three lignans, were isolated from the fruits of Gardenia jasminoides Eills. [Display omitted] • Seven undescribed compounds were isolated from the fruits of G. jasminoides. • Their structures were elucidated by NMR and mass spectrometry. • The absolute configurations were deduced by interpretation of ECD and [α] 20 D data. • The α -glucosidase inhibitory effects of all the isolated compounds were evaluated. [ABSTRACT FROM AUTHOR]

Fifteen undescribed diterpenoid quinones salviamilthone A-O (1 – 15), together with three known diterpenoid quinones (16 – 18), were isolated from the roots of Salvia miltiorrhiza Bunge. Their structures were elucidated using 1D and 2D NMR data, while the relative and absolute configurations were confirmed by NOESY correlations and comparison between experimental and calculated ECD spectra. In the evaluation of bioactivities, salviamilthone J (10), salviamone (18) (10 μM) significantly increased cell viability and decreased the expression of IL-1β in lipopolysaccharide-induced BEAS-2B cells. These data provide the molecular justification for the usage of Salvia miltiorrhiza in treating acute lung injury. Fifteen undescribed diterpenoid quinones were isolated from the dried roots of S. miltiorrhiza. [Display omitted] • Fifteen undescribed diterpenoid quinones were isolated from the dried roots of Salvia miltiorrhiza. • Their structures were elucidated by NMR and mass spectrometry. • All the isolated compounds were evaluated in vitro for their lung-protective effects. [ABSTRACT FROM AUTHOR]

Seven new diterpenoids quinones (1 – 6), together with five known ones (7 – 11), were isolated from the roots of Salvia miltiorrhiza Bunge. Their structures were elucidated by using 1D and 2D NMR data, while the relative and absolute configurations were confirmed by interpretations of the NOESY correlations and comparison of the experimental and calculated ECD spectra. In the evaluation of bioactivities, salviamilthiza C (3), significantly increased cell viability and decreased the expression of IL-1 β in LPS-induced BEAS-2B cells. [Display omitted] • Seven new diterpenoid quinones were isolated from the dried roots of Salvia miltiorrhiza. • Their structures were elucidated by NMR and mass spectrometry. • All the isolated compounds were evaluated in vitro for their lung-protective effects. [ABSTRACT FROM AUTHOR]

This study aimed to report the structure elucidation of the compounds isolated from Salvia miltiorrhiza , and their biological evaluations. Ten undescribed diterpenoid quinones and 10 known analogues were isolated from the dried roots of S. miltiorrhiza. Their structures were elucidated by extensive analysis, including nuclear magnetic resonance, high-resolution mass spectra, and ultraviolet and infrared spectra. Their absolute configurations were determined by comparing the experimental and calculated electronic circular dichroism spectra. In the evaluation of bioactivities, Salvianolactone acid I, epi -danshenspiroketallactone F, danshinspiroketallactone, grandifolia G, and 2 H -Naphtho [1,8- bc ]furan (10 μM) significantly increased cell viability and decreased the nuclear transport of p-P65 in lipopolysaccharide-induced bronchial epithelial cells. It was concluded that the diterpenoid quinones might belong to potent targeted lung-protective agents. Ten undescribed diterpenoid quinones were isolated from the dried roots of S. miltiorrhiza. [Display omitted] • Ten undescribed diterpenoid quinones were isolated from the dried roots of Salvia miltiorrhiza. • Their structures were elucidated by NMR and mass spectrometry. • All the isolated compounds were evaluated in vitro for their lung-protective effects. [ABSTRACT FROM AUTHOR]

Abstract: The extraction protocol of flavonoids from lotus (Nelumbo nucifera) leaves was optimized through an orthogonal design. The solvent was the most important factor comparing solvent, solvent:tissue ratio, extraction time, and temperature. The highest yield of flavonoids was achieved with 70% methanol–water and a solvent:tissue ratio of 30:1 at 4°C for 36h. The optimized analytical method for HPLC was a multi-step gradient elution using 0.5% formic acid (A) and CH3CN containing 0.1% formic acid (B), at a flow rate of 0.6mL/min. Using this optimized method, thirteen flavonoids were simultaneously separated and identified by high performance liquid chromatography coupled with photodiode array detection/electrospray ionization mass spectrometry (HPLC/DAD/ESI-MSn). Five of the bioactive compounds are reported in lotus leaves for the first time. The flavonoid content of the leaves of three representative cultivars was assessed under the optimized extraction and HPLC analytical conditions, and the seed-producing cultivar ‘Baijianlian’ had the highest flavonoid content compared with rhizome-producing ‘Zhimahuoulian’ and wild floral cultivar ‘Honglian’. [Copyright &y& Elsevier]