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A new steroid named persteroid ( 1 ) and seven known compounds ( 2 - 8 ) were isolated from the marine-derived fungus Penicillium sp. ZYX-Z-143. The structure of 1 was determined by HRESIMS, NMR, and ECD calculations. Compound 1 showed inhibitory activity against protein tyrosine phosphatase 1B (PTP1B) with IC 50 value of 46.31 ± 0.52 μM. Moreover, compound 1 potently suppressed nitric oxide (NO) production on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. The cytotoxicity and antibacterial activity of all isolates were tested.

In this study, analysis of the chemical constituents and bioactivities of the unpolar fractions [petroleum ether (PE) and chloroform (C)] of fruits and leaves of Alpinia oxyphylla Miq. were carried out, as well as the bioactivities of the main compounds nootkatone and valencene. From PE and C fractions of the fruits, and PE fraction of the leaves, 95.80%, 59.30%, and 82.11% of the chemical constituents respectively were identified by GC-MS. Among these identified compounds, nootkatone was the main compound in all of three fractions, while valencene was the second main compound in the PE fractions of the fruits and leaves. The bioactivities results showed that all of the fractions and the major compound nootkatone showed tyrosinase inhibitory, as well as inhibitory effect on NO production in LPS-stimulated RAW264.7 cells. While valencene only presented inhibitory activity on NO production in RAW264.7 cells. The critical genes involved in nootkatone biosynthesis in A. oxyphylla were identified from the public transcriptome datasets, and protein sequences were preliminarily analyzed. Our studies develop the usage of the unpolar fractions of A. oxyphylla , especially its leaves as the waste during its production, and meanwhile provide the gene resources for nootkatone biosynthesis.

A new oxygenated lanostane-type triterpenoid, 20 S ,24 S -epoxy-lanosta-7,9(11)-dien-3 β ,15 α ,25 R ,26-tetraol ( 1 ), together with three known compounds ( 2 - 4 ) were isolated from the fruiting bodies of Ganoderma weberianum . Extensive NMR spectrometry and HRESIMS analysis, as well as NMR and ECD calculations elucidated the structure of the new compound. 27-nor-3 β -hydroxylanosta-7,9(11),23 E -trien-25-one ( 2 ) showed superior α -glucosidase inhibitory activity with IC 50 value of 122.1 μM to that of positive control acarbose (304.6 μM).

Three phenolic compounds (± 1 and 2 ) including a pair of new enantiomers were isolated from the sclerotia of Inonotus obliquus . Their structures were assigned by extensive spectroscopic analyses. All the compounds were evaluated for the neuroprotective activity against oxidative damage on human neuroblastoma SH-SY5Y cells induced by H 2 O 2 . Compound 2 showed remarkable neuroprotective effect and significantly improved the cell viability of SH-SY5Y cells treated by H 2 O 2 .

A picrotoxane-type sesquiterpene, dendroterpene E ( 1 ), together with five benzene derivatives ( 2-6 ), were isolated from the stems of Dendrobium nobile Lindl. Their structures were elucidated by spectroscopic analysis and X-ray diffraction analysis. Compound 1 was a new picrotoxane-type sesquiterpene with a C-9/C-1/O/C-11 oxetane ring, which was first encountered in this type of compounds. Compounds 1-3 exhibited inhibitory activities against α -glycosidase.

Three new dimeric 2-(2-phenylethyl)chromones crassin I ∼ K ( 1 - 3 ), together with one known analogue ( 4 ), were isolated from the artificial holing agarwood originating from Aquilaria sinensis . Their structures including the absolute configuration were elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR, ECD), and HRESIMS analysis, as well as by comparison with the literature data. Compounds 1 and 2 exhibited weak acetylcholinesterase inhibitory activity.

During the course of searching for structurally interesting and bioactive compounds, a further chemical investigation of the leaves of Heynea trijuga Roxburgh was performed, which led to the isolation of a new ergostane derivative, named 3 β , 4 β , 20 S -trihydroxyergosta-5, 24(28)-dien-16-one ( 1 ), together with five known sterides (3 β , 23 S )-ergosta-5, 24(28)-diene-3, 23-diol ( 2 ), ergosta-5, 24(28)-diene-3 β -diol ( 3 ), stigmast-5-ene-3 β , 7 α -diol ( 4 ), sitoindoside I ( 5 ) and stigmast-3 β , 5 α , 6 β -triol ( 6 ). The structure of the new compound was elucidated using a combination of 1 D, 2 D NMR techniques and HR-EI-MS analyses. All the compounds were evaluated for cytotoxic activity against tumor cell line BEL-7402 by MTT method.

Three new 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromones and one new dimeric 2-(2-phenylethyl)chromone were isolated from the agarwood of Aquilaria crassna Pierre ex Lecomte in Laos. The structures of the isolates were elucidated by spectroscopic methods, and their configurations were determined via ROESY correlations, 3 J H-H coupling constants analyses, comparisons of chemical shifts and specific rotations with known compounds, and ECD calculation in the case of 1 . Compounds 1 - 4 were evaluated for their cytotoxicity. Compounds 1 and 2 exhibited weak cytotoxicity toward HeLa cell line (IC 50 : 49.8 ± 1.2 μM) and K562 cell line (IC 50 : 42.66 ± 0.47 μM), respectively.

One new havanensin-type limonoid ( 1 ) named trisinlin A with two known compounds (4 E ,8 E )-2-[2'-hydroxyhexadecanoyl amino]-4,8-octadecadiene-1,3-diol ( 2 ), 9-octadecenoic acid-2',3'-dihydroxypropyl ester ( 3 ) were isolated from the roots of Trichilia sinensis . The structure of the new compound was unambiguously determined through comprehensive spectroscopic analyses including 1D and 2D NMR, and mass spectrometry, as well as by comparison with the literature. Trisinlin A showed significant insecticidal activity against newly hatched larvae of Spodoptera litura .

A new iridoid, named nudifloside (1), together with three known compounds, was isolated from the EtOH extract of the aerial parts of Callicarpa nudiflora Hook. The structures were elucidated by a study of their physical and spectral data. Nudifloside (1) and the isolated known compound linearoside (2) displayed inhibitory effects towards chronic myelogenous leukaemia K562 cell line, with IC(50) values of 20.7 and 36.0 microg mL(-1), respectively.