Jian-Wei Dong

Proaporphine and aporphine alkaloids with acetylcholinesterase inhibitory activity from Stephania epigaea.

An unusual proaporphine alkaloid bearing an isopropanenitrile group at isoquinoline nitrogen, named epiganine A (1) and a new aporphine alkaloid, epiganine B (2), together with eight known alkaloids, pronuciferine (3), dehydrodicentrine (4), romerine (5), romeline (6), N-methylcalycinine (7), phanostenine (8), dicentrine (9), and N-methyllaurotetanine (10), were isolated from the roots of Stephania epigaea. The absolute configuration of 1 was determined by calculating electronic circular dichroism (ECD) and comparing with experimental data. Compounds 2 and 4 showed strong acetylcholinesterase (AChE) inhibitory effects with the IC50 values of 4.36 and 2.98μM, respectively. Compounds 5-9 also exhibited potent AChE inhibitory activities.

Three new diterpenoid alkaloids from the roots of Aconitum duclouxii.

Three new C19-diterpenoid alkaloids, ducloudines C (1), D (2), and E (3), were isolated from the roots of Aconitum duclouxii. Their structures were established on the basis of extensive spectroscopic analyses. Ducloudine C (1) is the first aconitine-type C19-diterpenoid alkaloid with a C = O group at C-3 and a C = C bond between C-1 and C-2. All compounds were tested for their biological activities against one pathogenic fungi and two pathogenic bacteria.

A new flavone C-glycoside and a new bibenzyl from Bulbophyllum retusiusculum.

Abstract A new flavone C-glycoside, apigenin 6-C-α-arabinofuranosyl 8-C-α-arabinopyranoside (1) and a new bibenzyl, bulbotetusine (2), were isolated from the tubers of Bulbophyllum retusiusculum. Their structures were established on the basis of extensive spectroscopic analyses. The absolute configuration of 2 was determined by the comparison of experimental and calculated electronic circular dichroism. Compounds 1 and 2 showed no obvious cytotoxic activity against any five human tumour cell lines with IC50 values >40 μM.

Production of a new tetracyclic triterpene sulfate metabolite sambacide by solid-state cultivated Fusarium sambucinum B10.2 using potato as substrate.

The aim of this work is to explore integracide analogues from secondary metabolites of microorganisms. A new tetracyclic triterpene sulfate was produced by solid-state fermentation (SSF) with Fusarium sambucinum B10.2. The tetracyclic triterpene sulfate was identified as (3S,5R,10S,11S,12S,13R,17R,20R)-4,4-dimethylergosta-8,14,24-triene-3,11,12-triol-12-acetate, 3-sulfate on the basis of HRESIMS, NMR and electronic circular dichroism (ECD) spectra and named sambacide (1). The antibacterial and antifungal assays of sambacide (1) showed significant antibacterial activities against Staphylococcus aureus and Escherichia coli. The fermentation conditions including culture media, fermentation temperature and time, were optimized. And potato was selected as the fermentation substrate, 28°C was used as the fermentation temperature, and 20-days fermentation time was determined for F. sambucinum-SSF to produce sambacide (1) with a high yield of 19.04±0.82g/kg. This paper provides an efficient approach to produce the antibacterial and antifungal agent sambacide (1) in a very high yield.

Innovative Approach to the Accumulation of Rubrosterone by Fermentation of Asparagus filicinus with Fusarium oxysporum

Rubrosterone, possessing various remarkable bioactivities, is an insect-molting C19-steroid. However, only very small amounts are available for biological tests due to its limited content from plant sources. Fungi of genus Fusarium have been reported to have the ability to convert C27-steroids into C19-steroids. In this study, Asparagus filicinus, containing a high content of 20-hydroxyecdysone, was utilized to accumulate rubrosterone through solid fermentation by Fusarium oxysporum. The results showed that F. oxysporum had the ability to facilitate the complete biotransformation of 20-hydroxyecdysone to rubrosterone by solid-state fermentation. The present method could be an innovative and efficient approach to accumulate rubrosterone with an outstanding conversion ratio.

A new phenylpropanoid glucoside and a chain compound from the roots of Allium tuberosum

Abstract A new phenylpropanoid glucoside tuberosinine D (1) and a chain compound (Z)-11R,12S,13S-trihydroxy-9-octadecenoate (2) were isolated from the roots of Allium tuberosum. The absolute configuration of 1 was established by comparing of experimental and calculated electronic circular dichroism. The absolute configuration of 2 was determined using the modified Mosher’s method for the first time.

Fermentation of Illigera aromatica with Clonostachys rogersoniana producing novel cytotoxic menthane-type monoterpenoid dimers

Illigera aromatica, a medicinal liana, was fermented with Clonostachys rogersoniana. Two novel menthane-type monoterpenoid dimers, dimericilligerates E (1) and F (2) were isolated from the fermented material. Their structures were identified by 1D/2D NMR, electric circular dichroism, derivatization, and Moshers method. A novel elimination reaction that formed a benzene ring from a menthane moiety afforded derivative 1a, which possesses more resolved NMR signals than the dimeric monoterpenoid, dimericilligerate E (1). The determination of 1a verified the estimation of 1. Compounds 1 and 2 showed potent cytotoxic activities; especially, 1 possessed significant activities against the liver hepatocellular carcinoma cell line (SMMC-7721) with an IC50 value of 3.89 ± 0.23 μM. Three novel precursors, dimericilligerates A–C (3–5), were identified by HPLC-MS and isolated from the original I. aromatica. This paper presents a novel class of monoterpenoid dimers and suggests that C. rogersoniana-fermented I. aromatica is effective to produce cytotoxic dimeric monoterpenoids from inactive original materials.

Five New Phenolic Compounds with Antioxidant Activities from the Medicinal Insect Blaps rynchopetera

Five new phenolic compounds rynchopeterines A–E (1–5), in addition to thirteen known phenolics, were isolated from Blaps rynchopetera Fairmaire, a kind of medicinal insect utilized by the Yi Nationality in Yunnan Province of China. Their structures were established on the basis of extensive spectroscopic analyses (1D and 2D NMR, HR-MS, IR) along with calculated electronic circular dichroism method. Rynchopeterines A–E (1–4) exhibited significant antioxidant activities with IC50 values of 7.67–12.3 μg/mL measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Besides, rynchopeterines B (2) and C (3) showed mild cytotoxicity against tumor cell Caco-2 and A549.

A novel sesquiterpene derivative with a seven-membered B ring from Illigera aromatica

Abstract A novel sesquiterpene derivative with a seven-membered B ring, illigerine (1), along with four known compounds, 1-epi-chiliophyllin (2), 3,4-dihydroxyphenethyl alcohol (3), coniferyl alcohol (4) and phenylpropionic acid (5), were isolated from Illigera aromatica S. Z. Huang et S. L. Mo. Their structures were identified by 1D/2D NMR, HRESIMS and electronic circular dichroism spectra and the cytotoxic activity and inhibitory effect of NO production in LPS-stimulated RAW264.7 were also evaluated. This is the first report of sesquiterpene isolated from the genus Illigera.

Cytotoxicity of the Defensive Secretion from the Medicinal Insect Blaps rynchopetera

Blaps rynchopetera Fairmaire has long been used as a folk medicine by the Yi and Bai ethnic groups in China to treat fever, cough, gastritis, boils, and tumors. In the present study, the cytotoxicity of the defensive secretion (TDS) of B. rynchopetera against AGS Caco-2, HepG2 U251 and Bel-7402 was tested, and the results revealed that TDS had potent cytotoxicity against testing cells with IC50 values of 45.8, 17.4, 53.6, 98.4 and 23.4 μg/mL, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis was employed to clarify the cytotoxic constituents in TDS of B. rynchopetera and five volatile compounds, including 2-ethyl-2,5-cyclohexadiene-1,4-dione (3, 31.00%), 1-tridecene (5, 28.02%), 2-methyl-2,5-cyclohexadiene-1,4-dione (2, 22.86%), hydroquinone (4, 1.33%), and p-benzoquinone (1, 1.01%), were identified. Chemical constituent investigation on TDS further supported the presence of 5 above compounds. A cytotoxic assay indicated that compounds 1, 2, 3 and 4 exhibited significant cytotoxicity against the testing cell lines, implying that benzoquinones and hydroquinone played important roles in the cytotoxicity of TDS of B. rynchopetera. TDS is a cytotoxic natural material and further studies investigating mechanisms and inhibitory activities on other cell lines is warranted.