Xue-Jiao Li

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.

Alkaloids with antioxidant activities from Aconitum handelianum

Abstract A new C20-diterpenoid alkaloid handelidine (1) and twenty-seven known alkaloids (2–28) were isolated from the roots of Aconitum handelianum. Their structures were established on the basis of extensive spectroscopic analyses. The study indicated that denudatine-type C20-diterpenoid alkaloids with vicinal-triol system and benzyltetrahydroisoquinoline alkaloids exhibited significant antioxidant activities measured by three antioxidant test systems. The aconitine-type C19-diterpenoid alkaloids could serve as potential secondary antioxidants for their strong binding effects to metal ions.

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.

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.

Improving Antioxidant Activity of Ophioglossum thermale Kom. by Fermentation with Talaromyces purpurogenus M18-11

Ophioglossum thermale Kom. was fermented with several fungi. The total phenolic and flavonoid contents (TPCs and TFCs) and antioxidant activities of fermented and non-fermented O. thermale (FOT and NFOT) were investigated. The results showed that Talaromyces purpurogenus M18-11 fermented O. thermale possessed significantly improved TPC and TFC and exhibited significantly stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) (half maximal inhibitory concentration (IC50) = 75.7 ± 2.1 μg mL) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) (IC50 = 20.52 ± 1.68 μg mL) free-radical scavenging activities, ferric reducing antioxidant power (0.585 ± 0.045 mmol g), and reducing power (half maximal effective concentration (EC50) = 30.52 ± 1.91 μg mL) than original material. The determination of the contents of representative flavonoids and their glucosides revealed that the improvements are attributed to the hydrolysis of homoisoflavonoid and flavonoid glucosides, glycometabolism, as well as fungal metabolites. This paper is the first to report the fermentation of O. thermale with pure strains and T. purpurogenus is an effective strain to process O. thermale for improving the antioxidant activity.

Simultaneous determination of alkaloids dicentrine and sinomenine in Stephania epigeae by 1H NMR spectroscopy

HIGHLIGHTSA qHNMR method for quantitation of dicentrine and sinomenine was developed.DMSO‐d6 enabled satisfactory separation of the signals to be integrated.Dimethyl terephthalate was selected as an internal standard for qHNMR.qHNMR is a feasible alternative to HPLC‐based methods for quantitation of alkaloids. ABSTRACT Stephania epigaea Lo is an important herbal medicine used as antiphlogistic and analgesic drugs. Its major components are dicentrine (1) and sinomenine (2). In the present study, a rapid, accurate, and precise method for simultaneous quantitation of dicentrine (1) and sinomenine (2) in S. epigeae using 1H NMR spectra was developed. The deuterated solvent of DMSO‐d6 enabled satisfactory separation of the signals to be integrated in 1H NMR spectrum and dimethyl terephthalate was selected as an internal standard. The feature signals of &dgr; 7.57 and 5.70 were selected for quantifying the dicentrine (1) and sinomenine (2), respectively. Validation of the quantitative method was performed in terms of specificity, accuracy, precision, and stability. This work implied that quantitative 1H NMR represents a feasible alternative to high‐performance liquid chromatography‐based methods for quantitation of dicentrine (1) and sinomenine (2) in S. epigeae and is suitable for the quality control of S. epigeae.

A new menthane-type monoterpenoid from fermented Illigera aromatica with Clonostachys rogersoniana 828H2

Abstract A new menthane-type monoterpenoid, illigerate E (1), as well as two known ones, (1R*,3R*,4S*,6R*)-6,8-dihydroxymenthol (2) and cis-4-hydroxy-5-(1-hydroxy-1-methylethyl)-2-methyl-2-cyclohexene-1-one (3), were isolated from fermented Illigera aromatica with Clonostachys rogersoniana 828H2. Their structures were identified by HRESIMS and 1D/2D NMR spectra. Their inhibitory effects of NO production in RAW 264.7 macrophages were estimated.