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Two new open-chain cytochalasins, xylarchalasins A and B (

One new cyclopentapeptide, cycloaspeptide H (

Two new open-chain cytochalasins, xylarchalasins A and B (1 and 2), together with six known analogues (3-8), were isolated from the endophytic fungus Xylaria sp. GDGJ-77B from the Chinese medicinal plant Sophora tonkinensis. Their structures were elucidated on the basis of comprehensive spectroscopic analysis. Compound 2 displayed moderate antibacterial activities against Bacillus subtilis and Escherichia coli with MIC values of 25 and 12.5 μg/mL, respectively.

Two new cyclopentapeptides, xylapeptide A (1) with an uncommon L-pipecolinic acid moiety, and xylapeptide B (2) having a common L-proline residue were identified from an associated fungus Xylaria sp. isolated from the Chinese medicinal plant Sophora tonkinensis. Their planar structures were elucidated by a comprehensive analysis of NMR and MS spectroscopic spectra. The absolute configurations were determined by Marfey’s method and single-crystal X-ray diffraction (Cu Kα) analysis. Xylapeptide A (1) is the first example of cyclopentapeptide with L-Pip of terrestrial origin and showed strong antibacterial activity against Bacillus subtilis and B. cereus with MIC value of 12.5 μg/mL.

During the dressing process of diamond wheel using laser/ultrasonic-vibration combined dressing method, the removal mode of the local materials on the surface of wheel with the use of laser’s heating effect transits from brittle fracture to plastic flow, so that the wear of diamond dresser can be reduced and the dressing efficiency and surface dressing quality can be improved. Using ANSYS analysis software, the three-dimensional units were used and the nonlinearity of the material’s thermophysical properties was taken into account, and thereby, the finite element model of the temperature field of the diamond wheel heated by the laser during the dressing process was constructed. Then, the distributions of the temperature field on the surface and section of the wheel under different technological parameter were acquired. Moreover, the temperature distribution of the dressed wheel under actual working conditions was measured using infrared temperature measurement method. The results indicate that, under the same working conditions, the simulation results using finite element model fit well with the measured values, i.e., the finite element model has important guiding significance to the selection of technological parameters in dressing.

A new compound, illiciumflavane acid (1), along with 13 known compounds (2–14), were isolated from the fruits of Illicium verum Hook. F. Their structures were elucidated through various spectroscopic methods, including 1D NMR (1H NMR, 13C NMR), 2D NMR (HMQC, HMBC and NOESY) and HRMS. The stereochemistry at the chiral centres was determined using CD spectrum as well as analyses of coupling constants and optical rotation data. Cytotoxicity evaluation of four compounds showed that illiciumflavane acid and (E)-1,2-bis(4-methoxyphenyl)ethene exhibited potential against A549 activities with IC50 values of 4.63 μM and 9.17 μM, respectively. The structure of a new compound isolated from the fruits of Illiciumverum has been determined by detailed spectroscopic analyses. Thecytotoxicity activities of four compounds were determined againstP-388, NUGC, HT-29 and A549 cancer cell lines. Illiciumflavane acid (1)and (E)-1,2-bis(4-methoxyphenyl)ethene (5) showed activites againstthe four cell lines that were comparable to cisplatin.

Drying characteristics of Thomson seedless grape at different drying temperatures (45°C, 40 °C, 35 °C and 30 °C) were investigated in a Constant Temperature and Humidity Testing Machine. 8 different thin layer mathematical drying models are selected to fitting the date. The logarithmic drying model is satisfactorily to describe the drying process of grapes. In addition, this paper also calculated the moisture effective diffusivity (Deff) of Thompson seedless grape during drying process, and 45 °C has the maximum value 3.0702·10-11 m2/s. The energy of activation (Ea) is 59.03 kJ/mol. This means it will take 3279.44 kJ to remove 1kg water from the grape samples.

The aim of this study was to investigate the characteristic of color changes in Thompson seedless grape during drying at 30°C, 35°C and 40°C air temperatures. The CIE LAB color system was used to measure the surface color of the grapes. It was found that browning began at middle period of drying, where parameters L* and b* decreased and parameter a* increased during drying. Color changes during browning process were described as a first-order kinetic model, where the activation energies for the parameters L*, a*, b*, and total color difference were respectively 40.19, 24.29, 35.43, and 39.46 kJ·mol1.

Osmanthus fragrans is a traditional economic and ornamental plant in China. Iridoid glycosides are one of the main active ingredients of this plant. The ethanol extract of O. fragrans’ seeds was analyzed by an HPLC method. The HPLC profile allowed the isolation of nuzhenide and GI-3 from O. fragrans’ seeds for the first time. A C18 column was used with a mixture of methanol and water as the mobile phase using a gradient elution technique. Nuzhenide and GI-3 as the major components were used successfully as chemical markers to determine the optimal time of O. fragrans’ seeds for collection. Experimental results show nuzhenide and GI-3 reached the highest level in the last ten days of April, with contents of 6.04 mg (g of dw)−1 and 13.24 mg (g of dw)−1, higher than that of olive seeds. The study showed that O. fragrans’ seeds can serve as a source of iridoid glycosides.

The extracts from leaves, heartwood, barks and roots of the Streblus asper were investigated for anti-HBV activities, separately. The results suggested that the MeOH extracts of the heartwood, barks, and roots exhibited good anti-HBV activities. Further investigations displayed that ethyl acetate and n-butanol soluble parts of their MeOH extracts showed more significant anti-HBV activities. Moreover, a new lignan, together with 11 known compounds, was isolated from n-butanol-soluble part of MeOH extract of the roots of S. asper. The structures were elucidated by spectroscopic methods, including 1D NMR ((1)H NMR, (13)C NMR), 2D NMR (HMQC, HMBC) and HR-EI-MS experiments. Compounds 1-3 were evaluated for their anti-HBV activities. Honokiol showed significant anti-HBV activity with IC(50) values of 3.14μM and 4.74μM for HBsAg and HBeAg with no cytotoxicity respectively, while lamivudine (3TC, positive control) exhibited weak anti-HBV activity with IC(50) values of 11.81μM and 25.80μM for HBsAg and HBeAg respectively.

Three new lignans, erythro-strebluslignanol (1), threo-7'-methoxyl strebluslignanol (2) and erythro-7'-methoxyl strebluslignanol (3), together with twelve known compounds were isolated from the n-butanol and chloroform fractions of the heartwood of Streblus asper. Their structures were elucidated through extensive spectroscopic methods, including MS and 2D NMR experiments (HMQC and HMBC). The stereochemistry at the chiral center was determined using CD spectra, as well as analysis of coupling constants and optical rotation data, respectively. Primary bioassays showed that 6-hydroxyl-7-methoxyl-coumarin (5) and ursolic acid (10) showed anti-HBV activities, with IC(50) values of 29.60 μM and 89.91 μM for HBsAg at no cytotoxicity, and IC(50) values of 46.41 μM and 97.61 μM for HBeAg at no cytotoxicity, respectively.

Two new metabolites named 6-oxo-de-O-methyllasiodiplodin (1) and (E)-9-etheno-lasiodiplodin (2), with three known compounds lasiodiplodin (3), de-O-methyllasiodiplodin (4), and 5-hydroxy-de-O-methyllasiodiplodin (5), were isolated from the mycelium extracts of a brown alga endophytic fungus (No. ZZF36) obtained from the South China Sea. Their structures were elucidated using spectroscopic methods, mainly 1D and 2D NMR. Additionally, the structure of compound 1 was confirmed by single crystal X-ray diffraction analysis. The antimicrobial activities of lasiodiplodins, and the 13-acetyl and 12,14-dibromo derivatives of lasiodiplodin were tested for the first time and the results were compared to each other.

(−)-Byssochlamic acid (1) was isolated from mangrove fungus (strain No. k38) from the South China Sea coast. This is the first time that 1 was found in nature. Its structure was confirmed by spectra data and X-ray diffraction analysis.

One new hydroanthraquinone dimer with a rare C-9–C-7′ linkage, nigrodiquinone A (1), and four known anthraquinone monomers 2–5, were isolated from a fungus Nigrospora sp. obtained from the zoanthid Palythoa haddoni collected in the South China Sea. The structure of 1 was established through extensive NMR spectroscopy, and the absolute configuration was elucidated by comparing computed electronic circular dichroism (ECD) and optical rotations (OR) with experimental results. All the compounds were evaluated for antiviral activity, and 1 was also evaluated for antibacterial activity. Compound 4 displayed mild antiviral activity against coxsackie virus (Cox-B3) with the IC50 value of 93.7 μM, and 5 showed an IC50 value of 74.0 μM against respiratory syncytial virus (RSV).

A new lignan, (7'R,8'R)-threo-strebluslignanol-2-O-beta-D-glucopyranoside, along with 8 known compounds (2-9) were isolated from the water-soluble part of the MeOH extract of the heartwood of Streblus asper. Their structures were elucidated through various spectroscopic methods, including 1D NMR (1H NMR, 13C NMR), 2D NMR (HMQC, HMBC, and NOESY), and HRMS. The stereochemistry at the chiral centers was determined using the CD spectrum, as well as analyses of coupling constants and optical rotation data. In the preliminary bioassay, the isolated compounds did not show anti-HBV activities in vitro using the HBV transfected HepG2.2.15 cell line.

Four new bisabolane-type sesquiterpenoids, aspergiterpenoid A (1), (−)-sydonol (2), (−)-sydonic acid (3), and (−)-5-(hydroxymethyl)-2-(2′,6′,6′-trimethyltetrahydro-2H- pyran-2-yl)phenol (4) together with one known fungal metabolite (5) were isolated from the fermentation broth of a marine-derived fungus Aspergillus sp., which was isolated from the sponge Xestospongia testudinaria collected from the South China Sea. Four of them (1–4) are optically active compounds. Their structures and absolute configurations were elucidated by using NMR spectroscopic techniques and mass spectrometric analysis, and by comparing their optical rotations with those related known analogues. Compounds 1–5 showed selective antibacterial activity against eight bacterial strains with the MIC (minimum inhibiting concentrations) values between 1.25 and 20.0 µM. The cytotoxic, antifouling, and acetylcholinesterase inhibitory activities of these compounds were also examined.

The title compound, C(21)H(30)O, was isolated from the soft coral Sinularia sp. The mol-ecule contains four alicyclic rings, all trans-fused, among which three six-membered rings are in different distorted chair conformations while a five-membered ring assumes an envelope form.

Four compounds, apicidin (1), N-methylharman (2), cylo (Phe-Tyr) (3) and indole-3-acetic acid (4) were isolated from the mangrove endophytic fungus ZZF42 from the South China Sea. Their structures were elucidated by spectral data. Compound 1 was first isolated from the marine fungus. Compound 2 was firstly isolated from marine microorganism. Compound 1 exhibited selective in vitro cytotoxicity towards KB ahd KBv200 with IC50 values of less than 0.78 microg/ml.

A new nonadride derivative, ( − )-1-hydroxybyssochlamic acid (1) and the known ( − )-byssochlamic acid (2) were isolated from mangrove fungus (strain No. k38) collected from the South China Sea coast. The structure and relative configuration of 1 were elucidated by spectral data and X-ray diffraction analysis. Primary bioassays showed that 2 had medium cytotoxic activity against HEp-2 and HepG2 Cells, and 1 exhibited weak activity.

In order to study the serological characteristics and genetic background of Bel subtypes, A, B and H antigens on the surface of red blood cells of the proband as well as his family and the anti-A, anti-B antibodies in their serum samples were detected by hemagglutination test; the A, B, H substances in saliva were determined by inhibitory agglutination test. The results indicated that the proband, his mother and his daughter all were identified to be Bel phenotype; his two sisters were identified to be ABel phenotype; his father, son and spouse were identified to be A, B and B phenotype respectively. It is concluded that the Bel subtype exists as family genetic characteristics in China.

Four sterols were isolated from a brown alga endophytic fungus NO. ZZF36 from the South China Sea. Their structures were identified as brassicaterol(2), ergosterol(2), ergosterol peroxide(3),7,22(E)-ergostadiene-beta,5alpha,6beta-triol(4) by spectroscopic methods.

A new lignan, (7′ R,8′ R)- threo-strebluslignanol-2- O-β-D-glucopyranoside, along with 8 known compounds (2–9) were isolated from the water-soluble part of the MeOH extract of the heartwood of Streblus asper. Their structures were elucidated through various spectroscopic methods, including 1D NMR (1H NMR, 13C NMR), 2D NMR (HMQC, HMBC, and NOESY), and HRMS. The stereochemistry at the chiral centers was determined using the CD spectrum, as well as analyses of coupling constants and optical rotation data. In the preliminary bioassay, the isolated compounds did not show anti-HBV activities in vitro using the HBV transfected HepG2.2.15 cell line.