Wei-Guang Shan

Ceriponols A-K, tremulane sesquitepenes from Ceriporia lacerate HS-ZJUT-C13A, a fungal endophyte of Huperzia serrata.

Tremulane sesquiterpenes ceriponols A-K, together with three known ones tremulenediol A, 11,12-dihydroxy-1-tremulen-5-one and conocenol B, were isolated from the cultures of Ceriporia lacerate, a fungal endophyte residing in the stems of the medicinal plant Huperzia serrata. Among these isolates, ceriponol B possessed an unprecedent 12-nortremulane skeleton. The structures of all isolates were elucidated by spectroscopic methods, including MS and NMR (1D and 2D) spectroscopic techniques. The cytotoxic activities of ceriponols A-K were evaluated against three human tumor cell lines (HeLa, HepG2, and SGC 7901). Ceriponols F and K exhibited moderate cytotoxicity against all the tested human cancer cell lines with IC50 values ranging from 32.3 ± 0.4 to 173.2 ± 1.5 μM, while ceriponol G showed slightly better cytotoxicity against a HeLa cell line.

Diterpenoids and a Diarylheptanoid from Hedychium coronarium with Significant Anti-Angiogenic and Cytotoxic Activities

Two new labdane diterpenoids, namely hedycoronals A and B (1 and 2, resp.), were isolated from the rhizomes of Hedychium coronarium, together with eight known diterpenoids, 4–11, and a known diarylheptanoid, 3. The structures of 1 and 2 were established by detailed interpretation of their 1D‐ and 2D‐NMR spectra and HR‐ESI‐MS data. Inhibitory activities against human umbilical vein endothelial cells (HUMECs) proliferation and cytotoxic activities against four cancer cell lines were assessed for all the isolates. Most of these metabolites showed moderate or potent cytotoxic activities against four cancer cell lines. Moreover, compounds 3 and 8 exhibited promising inhibitory activities against HUMECs with the IC50 values of 6.4 to 3.3u2005μM.

Bioactive metabolites from Penicillium sp. P-1, a fungal endophyte in Huperzia serrata

A chemical study of metabolites of the strain Penicillium sp. P-1, an endophyte from the stems of Huperzia serrata, furnished a new chromone derivative, (2S)-2,3-dihydro-7-hydroxy-6,8-dimethyl-2-[(E)-prop-1-enyl]- chroman-4-one (1), an enantiomer of a known compound, and seven known compounds 2–8. The structure and absolute configuration of 1 were established using spectroscopic methods, including extensive 2D NMR and CD analyses. Cytotoxic activity of compounds 1–3 against HeLa and HepG2 cell lines were evaluated, in which compounds 2 and 3 exhibited marked cytotoxic activity against HeLa cells.

Analysis and determination of diterpenoids in unprocessed and processed Euphorbia lathyris seeds by HPLC-ESI-MS

Euphorbia lathyris (Caper spurge) is a toxic and potent Chinese materia medica (T/PCMM). This study sought a method for identifying five diterpenoids (Euphorbia factors L1−L3, L7a and L8) with the spectra of UV and mass, quantifying three diterpenoids L1, L2, and L8 in crude extracts of unprocessed and processed E. lathyris seeds by liquid chromatography/electrospray ionization mass spectrometry (LC–ESI-MS). The analysis was achieved on an Agilent Eclipse XDB-C18 column (4.6 mm×150 mm i.d., 5 μm) with an isocratic elution with a mobile phase consisting of water and acetonitrile at a flow rate of 0.25 mL/min at column temperature of 30 °C and UV detection was set at 272 nm. An ESI source was used with a positive ionization mode. The calibration curve was linear in the ranges of 9.9–79 μg/mL for Euphorbia factor L1, 3.8–30.5 μg/mL for Euphorbia factor L2, and 1.0–20.6 μg/mL for Euphorbia factor L8. The average recoveries (n=6) of three diterpenoids were 98.39%, 91.10% and 96.94%, respectively, with RSD of 2.5%, 2.4% and 2.1%, respectively. The contents of the three diterpenoids in processed E. lathyris seeds were 3.435, 1.367 and 0.286 mg/g, respectively, which decreased more sharply than those in unprocessed E. lathyris seeds which were 4.915, 1.944 and 0.425 mg/g, respectively. The method is simple, accurate, reliable and reproducible, and it can be applied to control the quality of unprocessed and processed E. lathyris seeds.

Modified mixed nanomicelles with collagen peptides enhanced oral absorption of Cucurbitacin B: preparation and evaluation

Abstract Polymer nanoparticles modified with collagen peptides (CPs) are an attractive strategy for the oral delivery of active ingredients from Chinese medicine. Thus, in the present study, collagen cationic CPs were simply separated using ion-exchange resin from bovine CPs, to modify mixed nanomicelles (MMs) on the surface to improve the oral bioavailability of Cucurbitacin B (CuB). The physicochemical property of micelles was characterized, which confirmed the successful modification of the nanomicelles. CPs-modified nanomicelles in vitro were found to significantly increase cellular uptake and transportation. Compared to unmodified micelles, the quantity of CPs-modified micelles internalized by Caco-2 cells were 3.74 times greater and the cumulative transportation flux (AP-BL) was 2.81 times greater. The membrane transportation process of CuB-MMs-CPs was found to be associated with energy consumption and clathrin- and caveolin-mediated endocytosis. In vivo studies performed on rats indicated that in comparison to CuB and CuB-MMs, the relative bioavailability of CuB-MMs-CPs increased by 3.43 times and 2.14 times, respectively. In addition, the tumor inhibition caused by CuB-MMs-CPs was increased significantly. Therefore, the nanomicelles co-modified with isolated CPs could act as attractive carriers for oral delivery of CuB.

Alkaloids and Nucleoside Derivatives from a Fungal Endophyte of Huperzia serrata

Endophytes are microorganisms growing in the tissues of their host plants without causing apparent disease symptoms [1]. The host plants offer the endophytes a unique biotope, the growth in which involves continual metabolic interactions with the hosts. Such interactions may enhance the synthesis of secondary metabolites [2]. Hence, endophytes represent an untapped source of bioactive secondary metabolites. In our previous investigation on fungal endophytes from Huperzia serrata, one strain, Penicillium sp. HS-3 (code name for this strain), was isolated from the stems of the plant and furnished four diketopiperazine alkaloids in liquid potato-dextrose medium [3]. Subsequent study indicated that this fungus can also produce alkaloids in liquid Sabouraud s medium. To investigate the metabolites of this fungus in liquid Sabouraud s medium, scaledup fermentation was carried out. The fungus was cultivated in 500 mL Erlenmeyer flasks each containing 300 mL liquid Sabouraud s medium (peptone 10 g; glucose 40 g for 1 L) to a total of 60 L at 28 C. The flasks were first incubated on rotary shakers for 6 days at 185 rpm, and then cultivated for another 20 days without agitation. The culture was filtered through cheesecloth. The broth was condensed to a volume of 4 L and then adjusted with 0.5 M HCl to pH 4. The acidic mixture was extracted with EtOAc (6 4 L), and the organic phase was condensed under reduced pressure to give a nonalkaloid residue (47.7 g). The aqueous phase was brought to pH 10 by addition of 1 M Na2CO3 and partitioned with chloroform (6 0.5 L) to give the crude alkaloids (4.3 g), which were then subjected to column chromatography (CC) on MCI-CHP20P gel eluted with MeOH–H2O (2:3 9:1) to afford three major fractions A–C. Fraction A was applied to silica gel CC (SiO2, CHCl3–MeOH 20:1) to yield 1 (24.3 mg). Fraction B was separated by CC (SiO2, CHCl3–MeOH 15:1) to give 2 (2.8 mg). Fraction C was also purified by CC (RP-18, MeOH–H2O 4:6) to afford 3 (8.7 mg). The nonalkaloid residue was first subjected to CC (SiO2, CHCl3–MeOH 20:1 10:1) to offer four fractions D–G. Fraction E (2.7 g) was then subjected to CC (MCI-CHP20P gel, MeOH–H2O 2:3 9:1) to give two subfractions E1 and E2, which were further purified by CC (HW-40C, MeOH) to furnish 4 (23 mg) and 6 (4 mg), respectively. Fraction F (4.3 g) was also separated by CC (MCI-CHP20P gel, MeOH–H2O 0:10 1:3) to give two subfractions F1 and F2, both of which were subjected to CC (RP-18, MeOH–H2O 1:9) as the final step of purification to give 7 (6.7 mg) and 5 (17.4 mg), respectively. The structures of the isolates were elucidated on the basis of detailed analysis of their spectroscopic data, including NMR and MS spectra. They were identified as perlolyrine (1), harmane (2), norharmane (3), cyclo(D-Pro-L-Trp) (4), thymidine (5), 5 -O-acetylthymidine (6), and 5 -O-acetyluridine (7). NMR signal assignments of compounds 1–7 were made by elucidating the two-dimensional NMR spectra and by comparing the data with those in the literatures.

New cytotoxic phloroglucinol derivatives from Agrimonia pilosa

Three new phloroglucinol derivatives, namely agripinol A-C (1-3), were isolated from Agrimonia pilosa Ledeb, along with two known ones (4-5). Their structures were characterized by spectroscopic methods, including MS and NMR spectroscopic techniques. The absolute configurations of the new compounds were unambiguously established by single crystal X-ray diffraction analyses. In the cytotoxicity assay, all compounds exhibited more potent cytotoxic activities against HCT-116, MDA-MB-231 and PC-3, as compared with the positive control fluorouracil.