Chiisanoside and chiisanogenin, which have been reported to have various bioactivities, were the most representative components of the leaves of Eleutherococcus sessiliflorus. The purpose of this study was to establish an optimal harvest period to increase bioactive chemical components and to utilize them as industrial crop materials under the quality control process of E. sessiliflorus. The extraction conditions of leaves were optimized to maximize the main two components using response surface methodology with a Box-Behnken design. The chemical structures of compounds 1–18 isolated from leaves under optimal extraction conditions were identified via NMR and HRMS. Using the chemical profile of leaves by the established UPLC-QTOF-MS and PDA methods, the yields of chiisanoside and chiisanogenin were inversely proportional, and the optimal harvest time from April to September was determined as July for those two components. This study could be used to develop high-quality products, including functional medicinal crops and health supplements, using E. sessiliflorus leaves.

This study was to assess the possibility of using competitive and slow binding experiments with affinity-based ultrafiltration UPLC-QTof-MS analysis to identify potent bacterial neuraminidase (bNA) inhibitors from the Broussonetia papyrifera roots extract. To isolate unbound compounds from the enzyme-binding complex, the root bark extracts were either incubated in the absence of bNA, in the presence of bNA, or with the time-dependent bNA before the ultrafiltration was performed. Thirteen flavonoids were separated from the target extract, and their inhibitory activities were tested against bNA. The isolated flavonoids exhibited potent inhibition against NA (IC50 =0.7-54.0 mu M). Our kinetic analysis of representative active flavonoids (1, 2, and 6) showed slow and time-dependent reversible inhibition. Additionally, chalcones exhibited noncompetitive inhibition characteristics, whereas flavonols and flavans showed mixed-type behavior. The computational results supported the experimental behaviors of flavonoids 2, 6,10, and 12, indicating that bounded to the active site, but flavonoids 6 and 10 binds near but not accurately at the active site. Although this is mixed-type inhibition, their binding can be considered competitive. (C) 2021 Published by Elsevier B.V.

Nineteen compounds were isolated from the stems of Maackia amurensis by activity-guided screening for new human monoamine oxidase-B (hMAO-B) inhibitors. Among the compounds isolated, flavonoids calycosin (5) and 8-O-methylretusin (6) were found to potently and selectively inhibit hMAO-B (IC50 = 0.24 and 0.23 mu M,respectively) but not hMAO-A with high selectivity index (SI) values (SI = 293.8 and 81.3, respectively). In addition, 5 and 6 reversibly and competitively inhibited hMAO-B with K-i values of 0.057 and 0.054 mu M. respectively. A pterocarpan (-)-medicarpin (18) was also observed to strongly inhibit hMAO-B (IC50 030 mu M). Most of the compounds weakly inhibited AChE, except isolupalbigenin (13) (IC50 = 20.6 mu M), which suggested 13 be considered a potential dual function inhibitor of MAO-B and AChE. Molecular docking simulation revealed that the binding affinities of 5 and 6 for hMAO-B (both -9.3 kcal/mol) were higher than those for hMAO-A (-7.4 and -7.2 kcal/mol, respectively). Compound 5 was found to interact by hydrogen bonding with hMAO-B at Cys172 residue (distance: 3.250 A); no hydrogen bonding was predicted between 5 and hMAO-angstrom. These findings suggest that compounds 5 and 6 be considered novel potent, selective, and reversible hMAO-B inhibitors and candidates for the treatment of neurological disorders. (C) 2020 Elsevier B.V. All rights reserved.

Cancer is caused by uncontrolled cell division and is a leading cause of mortality worldwide. Oenothera odorata (O. odorata) extract is used in herbal medicine to inhibit inflammation, but its potential anti-tumor properties have not been fully evaluated. Here, we demonstrated that O. odorata extract inhibits the proliferation of lung adenocarcinoma and melanoma cell lines In Vitro, and also inhibits the growth of melanoma cells In Vivo. After partitioning the extract with n-hexane, chloroform, ethyl acetate, and n-butanol, it was found that the butanol-soluble (OOB) and water-soluble (OOW) fractions of O. odorata extract are effective at inhibiting tumor cell growth In Vivo although OOW is more effective than OOB. Interestingly, these fractions did not inhibit the growth of non-cancerous cells. The anti-proliferative effects of the OOW fraction were found to be mediated by inhibition of glycolysis and cellular respiration. UPLC of both fractions showed two major common peaks, which were predicted to be hydrolyzable tannin-related compounds. Taken together, these data suggest that O. odorata extract has anti-tumor properties, and the molecular mechanism involves metabolic alterations and inhibition of cell proliferation. O. odorata extract therefore holds promise as a novel natural product for the treatment of cancer.

Scutellaria baicalensis Georgi (Scutellariae Radix) has been widely used as a dietary ingredient and traditional herbal medicine such as diuretic, hyperlipidemia, antibacterial, antiallergy, anti-inflammatory and anticancer properties. In this study, the isolation of biomarkers or bioactive compounds from complex S. baicalensis extracts represents an essential step for de novo identification and bioactivity assessment. The bioactive fraction consisted of eight compounds which was chromatographed on an analytical high performance liquid chromatography column using two different gradient runs. A simulative replacement of the analytical column with a medium pressure liquid chromatography and open column allowed the determination of gradient profile to allow sufficient separation in the preparative scale. From the optimized method, eight standard compounds have been identified in the fractions. In addition, MS, UV, HRMS detection was provided by ultraperformance liquid chromatographyequadrupole time-of-flight mass spectrometry (UPLC-QTof-MS) of all fractions. Therefore, this scale up procedure was successfully applied to a S. baicalensis extract.