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Dobinin K is a novel eudesmane sesquiterpenoids compound isolated from the root of Dobinea delavayi and displays potential antiplasmodial activity in vivo. Here, we evaluate the antiplasmodial activity of dobinin K in vitro and study its acting mechanism. The antiplasmodial activity of dobinin K in vitro was evaluated by concentration-, time-dependent, and stage-specific parasite inhibition assay. The potential target of dobinin K on Plasmodium falciparum was predicted by transcriptome analysis. Apoptosis of P. falciparum was detected by Giemsa, Hoechst 33258, and TUNEL staining assay. The reactive oxygen species (ROS) level, oxygen consumption, and mitochondrial membrane potential of P. falciparum were assessed by DCFH-DA, R01, and JC-1 fluorescent dye, respectively. The effect of dobinin K on the mitochondrial electron transport chain (ETC) was investigated by enzyme activity analysis and the binding abilities of dobinin K with different enzymes were learned by molecular docking. Dobinin K inhibited the growth of P. falciparum in a concentration-, time-dependent, and stage-specific manner. The predicted mechanism of dobinin K was related to the redox system of P. falciparum. Dobinin K increased intracellular ROS levels of P. falciparum and induced their apoptosis. After dobinin K treatment, P. falciparum mitochondria lost their function, which was presented as decreased oxygen consumption and depolarization of the membrane potential. Among five dehydrogenases in P. falciparum ETC, dobinin K displayed the best inhibitory power on NDH2 activity. Our findings indicate that the antiplasmodial effect of dobinin K in vitro is mediated by the enhancement of the ROS level in P. falciparum and the disruption of its mitochondrial function. [ABSTRACT FROM AUTHOR]

Two new farnesane sesquiterpenoid glycosides, rubusdelosides A and B (1 and 4), together with five known farnesane sesquiterpenoids (2, 3, and 5-7), and two known meroterpenoids (8 and 9), were isolated from water extract of the herbs of R. delavayi. Their structures were identified by the comprehensive analyses of physicochemical properties and spectroscopic data (NMR and HR-ESI-MS). Compounds 1-8 showed moderate in vivo anti-T. spiralis activities. [ABSTRACT FROM AUTHOR]

Three new benzophenone glycosides, 2-O-β-D-glucopyranosyl-6,3',4'-trihydroxy-4-methoxybenzophenone (1), 4'-O-β-D-glucopyranosyl-2,4,6,3'-tetramethoxybenzophenone (2) and 2-O-β-D-glucopyranosyl-4'-hydroxy-6-methylbenzophenone (3), and a new flavonoid glycoside 5'-hydroxyombuoside (6), along with three known phenolic glycosides 4-O-β-D-glucopyranosyl-2,6,4'-trihydroxybenzophenone (4), mangiferin (5), and ombuoside (7), were isolated from the 80% ethanol extract of roots of Dobinea delavayi. Their structures were determined by the comprehensive analyses of the physicochemical properties and spectroscopic data (1D NMR, 2D NMR, and HR-ESI-MS). Cytotoxicity and in vitro antimalarial activity of compounds 1, 3, 4, 6, and 7 were evaluated by MTT colorimetric assay and β-hematin formation inhibition assay, respectively. [ABSTRACT FROM AUTHOR]

Four previously undescribed hydroxypropionylated d-glucose derivatives, astrabhotins A–D (1–4), along with ten known compounds α-d-glucose (5), β-d-glucose (6), quebrachitol (7), 3-hydroxypropionic acid (8), oleic acid (9), isoliquiritigenin (10), liquiritigenin (11), odoratin (12), 7β-hydroxysitosterol (13) and daucosterol (14), were isolated from the roots of Astragalus bhotanensis. Their structures were elucidated based on the analyses of extensive spectroscopic data and physicochemical properties. Astrabhotin A (1) reduced the writhing response remarkably with 52.5% inhibition by acetic acid induced writhing test. The analgesic effect of 1 was stronger than the standard drug aspirin. In addition, compounds 1 and 3 showed significant antioxidant activities with IC50 values of 9.9 ± 0.2 and 7.9 ± 0.4 μg/mL, and exhibited weak or moderate cytotoxicity against HepG2 cells with IC50 values of 106.6 ± 2.7 and 42.0 ± 0.9 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

A new prenylated coumestan, campylohirtin A (1), along with fifteen phenolic known compounds (2‒16) and four other known compounds (17‒20), was obtained from the 95% ethanol extract of roots of Campylotropis hirtella. Their structures were elucidated based on extensive spectroscopic analysis (1 D and 2 D-NMR, MS, UV and IR). In vitro antimalarial activities of compounds 1−3, 5−14 and 16 were evaluated by β-hematin formation inhibition assay. Compared with the positive control chloroquine diphosphate, compounds 8, 11 and 16 exhibited strong antimalarial activity with the IC50 values of 69.9, 33.2 and 75.4 µM, respectively. Compounds 1−3, 5−7 and 12 showed moderate antimalarial activities with IC50 values ranging from 134.6 µM to 578.6 µM. [ABSTRACT FROM AUTHOR]

Astragali Radix (Huangqi) is one of the well-known traditional Chinese medicines and has been used in China for more than two thousand years. As a close species, Astragalus dolichochaete Diels was found to possess cytotoxicity during our preliminary study of Astragalus plants from Yunnan Province, China. To better understand the chemical foundation of the cytotoxicity, the major constituents of A. dolichochaete were studied. As a result, two new 8-isopentenyl isoflavane derivatives, dolichochaeteins A and B (1 and 2), together with ten known constituents were isolated, and their structures were elucidated by means of spectroscopy, mainly 1D and 2D NMR techniques. The cytotoxic activities were evaluated for the raw extract, ethyl acetate fraction, compound 2 and glyasperin H (3) against human gastric carcinoma cell line SGC-7901, human hepatoma cell line SMMC-7721 and human leukemic cell line K562. All the samples exhibited significant cytotoxicity. [ABSTRACT FROM AUTHOR]

Astragalus ernestii has been used as a substitute for Radix Astragali (Huang-Qi) in southwest China. To better understand the chemical rationale for the medicinal usage, the phytochemistry of A. ernestii was recently studied. As a result, a novel aurone-phenylpropanoid adduct astrernestin (1), together with five known phenoloids calycosin-7-O-β-D-glucopyranoside (2), 4,4′-dimethoxy-3′-hydroxy-7,9′:7′,9-diepoxylignan-3-O-β-D-glucopyranoside (3), syringaresinol-4-O-β-D-monoglucoside (4), hedyotol D 4″-O-β-D-glucopyranoside (5) and trifolirhizin (6), were isolated from the roots of A. ernestii. The structure of compound 1 was elucidated by extensive spectroscopic analysis and optical rotation calculation. [ABSTRACT FROM AUTHOR]

A new lignan glycoside, astrayunoside A (1), along with eight known compounds (2–9), were obtained from the methanol extract of roots of Astragalus yunnanensis. All the compounds were obtained from A. yunnanensis for the first time. Their structures were elucidated by extensive spectroscopic analysis (1D and 2D-NMR, MS, UV, CD, and IR). The weak antibacterial activities of the crude extracts of A. yunnanensis against Staphyloccocus aureus, Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa, Shigella dysenteriae, Salmonella typhi H901, Candida albicans, Streptococcus mutans, and Actinomyces viscosus were observed. [ABSTRACT FROM AUTHOR]

Two new abietane diterpenoid glucosides, talienosides A and B (1 and 2), along with four known compounds (3 – 6), were isolated from the ethyl acetate soluble portion of 70% acetone extract of the underground parts of Isodon taliensis. Their structures were elucidated based on the analyses of extensive spectroscopic data and physicochemical properties. The two new compounds were tested for their bioactivities against malaria and diabetes by β-hematin formation inhibition and α-glycosidase inhibition experiments, respectively. However, only 2 showed weak β-hematin formation inhibitory activity. [ABSTRACT FROM AUTHOR]