Harzianic acids and oxazolidinone from the endophytic fungus Ilyonectria sp. and their cytotoxicity activity

Four undescribed compounds including three harzianic acids (1, 3 and 4) and one oxazolidinone (2), along with three known ones (5-7) were isolated from the solid fermented product of endophytic fungus Ilyonectria sp., their structures were elucidated as 1-amino-harzianic acid (1), ilyonectria-oxazolidinone (2),10'-nor- isoharzianic acid (3), isohomoharzianic acid (4), harzianic acid (5), isoharzianic acid (6), homoharzianic acid (7) by means of detailed chemical evidences and spectroscopic data analysis. All the compounds were evaluated for cytotoxicity against SMMC-7721 human cancer cell lines by MTS assay. Among the seven tested compounds, 1-amino-harzianic acid (1) demonstrated well cytotoxic activity against SMMC-7721 with IC50 value of 26.84 μM. The results of molecular docking indicated that compound exhibited moderate anti-tumor activity may through binding to apoptosis related proteins.

Chromones from the endophytic fungus Bipolaris eleusines

Eight previously undescribed chromones eleusineketones A-H (1-8), as well as eight known compounds (9-16), were isolated from the endophytic fungus Bipolaris eleusines. These planar structures were created using an in-depth analysis of their spectral data, which included 1D, 2D, and HRESIMS data. Furthermore, the absolute configurations of compounds 1, 2, and 6 were determined by spectroscopic analysis and quantum chemical computational approaches, and compound 5 was determined by single-crystal X-ray diffraction analysis. The cytotoxic activity assay revealed that compounds 1 and 5 both inhibited MDA-MB-231 cells with IC50 values of 14.48 μM and 17.99 μM, respectively.

The antifungal properties of terpenoids from the endophytic fungus Bipolaris eleusines

A series of terpenoids (1-17), comprising six new compounds designated bipolariterpenes A-F (1-6) and eleven recognized compounds (7-17), were isolated from the wheat culture of the potato endophytic fungus Bipolaris eleusines. Their structures and stereochemistry were clarified by HRESIMS, NMR, DP4 + probability analyses, and computations for electronic circular dichroism (ECD). All compounds are made up of six meroterpenoids, four sesterterpenes and seven sesquiterpenes. Among them, four sesterterpenes (4, 5, 10, 11) were investigated for their antifungal, antibacterial and cytotoxic properties, and six meroterpenoids (1-3, 7-9) were evaluated for their antifungal properties. The compounds 7, 9, and 10 had substantial antifungal activity against Epidermophyton floccosum at a concentration of 100 µM. No antibacterial and cytotoxic activities were observed.

Boerelasins A-D, Four Unprecedented Cytochalasins from the Endophytic Fungus Boeremia Exigua

Four undescribed cytochalasins (1-4) were isolated from the endophytic fungus Boeremia exigua. Structurally, boerelasin A (1) represents the first example of a cytochalasin with a rare 5/5 bicyclic carbon core. Boerelasin B (2) possesses an unprecedented 5/6/5/6/8 pentacyclic ring system. Boerelasin C (3), a derivative from the common biosynthetic intermediate to 1, is a macrocyclic ring-opening cytochalasin, and boerelasin D (4) contains an uncommon six-carbon alkyl acid side chain. The structures were elucidated based on spectroscopic methods, electronic circular dichroism, spin-spin coupling constants, and calculated nuclear magnetic resonance with DP4+ analysis. These compounds exhibited significant cytotoxicity against the tumor cells.

Paecilins F–P, new dimeric chromanones isolated from the endophytic fungus Xylaria curta E10, and structural revision of paecilin A

A total of eleven new dimeric chromanones, paecilins F-P (2–12), were isolated from the endophytic fungus Xylaria curta E10, along with four known analogs (1, 13–15). Their structures and absolute configurations were determined by extensive experimental spectroscopic methods, single-crystal X-ray diffraction, and equivalent circulating density (ECD) calculations. In addition, the structure of paecilin A, which was reported to be a symmetric C8-C8′ dimeric pattern, was revised by analysis of the nuclear magnetic resonance (NMR) data, and single-crystal X-ray diffraction. Compound 1 showed antifungal activity against the human pathogenic fungus Candida albicans with a minimum inhibitory concentration of 16 μg/mL, and Compounds 8 and 10 showed antibacterial activity against the gram-negative bacterium Escherichia coli with the same minimum inhibitory concentration of 16 μg/mL.

Oblongolides from endophytic fungus Phoma bellidis Neerg. harbored in Tricyrtis maculata (D. Don) J.F.Macbr

Five previously undescribed oblongolides, namely phomaones A-E, along with four known compounds, were isolated from the endophytic fungus Phoma bellidis Neerg.. Their structures and absolute configurations were determined by extensive experimental spectroscopic methods as well as single crystal X-ray diffractions, ECD calculations and GIAO ¹³C NMR calculations. Phomaone A represent the first example of oblongolides with glycol directly linked by two C-C bonds, and its biosynthetic pathway were proposed. The cytotoxicity of obtained compounds was evaluated against human cancer cell lines MCF-7, DU145, and SW480. All compounds except phomaone A showed the cytotoxicity against MCF-7 with IC₅₀ value ranging from 12.45 to 49.84 μM.

Four New Highly Oxygenated Eremophilane Sesquiterpenes from an Endophytic Fungus Boeremia exigua Isolated from Fritillaria hupehensis

Four new eremophilane-type sesquiterpenes, boeremialanes A–D (1–4) were obtained from solid substrate cultures of Boeremia exigua (Didymellaceae), an endophytic fungus isolated from Fritillaria hupehensis (Liliaceae). Boeremialanes A–C (1–3) are highly oxygenated eremophilanes with a benzoate unit attached at the C-13 position and are rarely found in nature. Their structures and absolute configurations were determined by extensive spectroscopic methods, electronic circular dichroism (ECD), and nuclear magnetic resonance (NMR) calculations with DP4+ analysis. Boeremialane D (4) potently inhibited nitric oxide production in lipopolysaccharide-treated RAW264.7 macrophages with an IC₅₀ of 8.62 μM and was more potent than the positive control, pyrrolidinedithiocarbamate (IC₅₀ = 23.1 μM).

Ophiorrhines F and G, Key Biogenetic Intermediates of Ophiorrhine Alkaloids from Ophiorrhiza japonica and Their Immunosuppressant Activities

Continued interest in bioactive alkaloids led to the isolation of two undescribed alkaloids, ophiorrhines F (1) and G (2), from the aerial parts of Ophiorrhiza japonica. Their structures were elucidated based on spectroscopic methods, electronic circular dichroism, and calculated NMR with DP4+ analysis. These two alkaloids represent key biological genetic intermediates in the formation of ring C in the ophiorrhines. Compound 1 exhibited good inhibition on LPS-induced B cell proliferation with an IC₅₀ value of 0.38 μM and showed significant selective inhibitory activity on a B cell proliferation response with a selective index of 548.42. A preliminary study indicated that 1 may have a new mechanism of immunosuppression.

Three new pyrrole alkaloids from the endophytic fungus Albifimbria viridis

Three new pyrrole alkaloids albifipyrrols A-C (1-3), were isolated from the endophytic fungus Albifimbria viridis collected from the Chinese medicinal plant. Their structures were elucidated by extensive NMR and HRESIMS spectrometric analyses. All compounds were evaluated for immunosuppressive activity. Fortunately, compound 2 exhibits certain inhibition specifically against the LPS-induced proliferation of B lymphocyte cells with IC₅₀ value 16.16 μM.

Immunosuppressive Isopimarane Diterpenes From Cultures of the Endophytic Fungus Ilyonectria robusta

Five new isopimarane diterpenes, robustaditerpene A-E (1–5), which include 19-nor-isopimarane skeleton and isopimarane skeleton, were isolated from the liquid fermentation of the endophytic fungus Ilyonectria robusta collected from Bletilla striata. The structure elucidation and relative configuration assignments of all compounds were accomplished by interpretation of NMR and HRESIMS spectrometric analyses and ¹³C NMR calculation. And the absolute configuration of 1-5 were identified by single-crystal X-ray diffraction and ECD calculation. Compound 3 inhibited lipopolysaccharide-induced B lymphocytes cell proliferation with an IC₅₀ value at 17.42 ± 1.57 μM while compound 5 inhibited concanavalin A-induced T lymphocytes cell proliferation with an IC₅₀ value at 75.22 ± 6.10 μM. These data suggested that compounds 3 and 5 may possess potential immunosuppressive prospect.

Bipolarithizole A, an antifungal phenylthiazole-sativene merosesquiterpenoid from the potato endophytic fungus Bipolaris eleusines

Bipolarithizole A (1) is a phenylthiazole-sativene sesquiterpenoid hybrid isolated from the fungus Bipolaris eleusines. It shows anti-pathogenic fungi activity against Rhizoctonia solani with an MIC value of 16 μg mL−1.

Secondary Metabolites of the Endophytic Fungus Chaetomium globosum Isolated From Coptis chinensis

A new steroid, chaetglotone (1), together with 3 known compounds (2-4), were isolated from Chaetomium globosum, which is an endophytic fungus isolated from the root of Coptis chinensis Franch . The new compound was characterized by one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy and high-resolution electrospray ionization mass spectrometer. The relative configuration and absolute configuration of 1 were further determined via the DP4 + and Early Childhood Development protocols, separately.

Structure and cytotoxicity of trichothecenes produced by the potato-associated fungus Trichothecium crotocinigenum

Seven previously undescribed trichothecenes, named trichothecrotocins M-S (1-7), along with five known compounds, were isolated from rice cultures of the potato-associated fungus Trichothecium crotocinigenum. Their structures and absolute configurations were determined through spectroscopic methods, single-crystal X-ray diffraction, and quantum chemistry calculations on ECD. Compound 1 possesses a rare 6,11-epoxy moiety in the trichothecene family. Compound 6 exhibited strong cytotoxic activity against MCF-7 cancer cell lines with an IC₅₀ value of 2.34 ± 0.45 μM. It promoted apoptosis induction in MCF-7 cells. Moreover, cell cycle analysis showed cell cycle arrest caused by compound 6 at the G2/M phase which resulted to cell proliferation inhibition and pro-apoptotic activity. Further quantitative real-time PCR (qRT-PCR) analysis confirmed that the G2/M arrest was accompanied by upregulation of p21 and down regulation of cyclins B1 in 6-treated MCF-7 cells.

Identification and Bioactivities of Secondary Metabolites Derived from Endophytic Fungi Isolated from Ethnomedicinal Plants of Tujia in Hubei Province: A Review

Tujia is a national minority, inhabiting in the mountainous Wuling area in China. Since 1978, Tujia medicine has been studied, summarized and developed, leading to numerous achievements by Chinese researchers, such as the publishing of approximately 30 monographs of Tujia medicine. These publications are focused on summarizing and improving the theory of Tujia medicine and developing clinical therapies from this system of medicine. The shortage of natural medicinal plants used in Tujia medicine has created the need to discover new resources to replace them and protect endangered natural plant species. Endophytic fungi are one of the conservation options, are considered a source of new bioactive natural products, and are a renewable and inexhaustible source of new drugs and agrochemicals. This review summarizes 260 compounds from endophytic fungi that have been previously isolated from the medicinal plants of Tujia. These compounds include steroids, terpenoids, meroterpenoids, polyketides, alkaloids, peptides, aliphatic compounds, aromatic compounds, and heterocyclic compounds.

Bioactive Polyketides From the Potato Endophytic Fungus Aspergillus carneus

A previously undescribed polyketide (1) and 3 known analogs (2-4) were obtained from cultures of the potato endophytic fungus Aspergillus carneus. The structures were elucidated on the basis of extensive nuclear magnetic resonance spectroscopic data. The absolute configuration of 1 was further determined by electronic circular dichroism and optical rotation calculations. Compounds 1-4 showed moderate antifungal activity against plant pathogens. Compounds 1, 2, and 4 inhibited nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells, with half-maximal inhibitory concentration values of 13.36, 30.16, and 51.47 µM, respectively. Compound 4 showed effective antioxidant activity.

Trichothecrotocins D-L, Antifungal Agents from a Potato-Associated Trichothecium crotocinigenum

Seven new merosesquiterpenoids, trichothecrotocins D-J (1-7), two new trichothecene sesquiterpenoids, trichothecrotocins K (12) and L (13), and six known compounds (8-11, 14, and 15), were isolated from a potato-associated fungus, Trichothecium crotocinigenum. Compounds 5 and 6 were racemates which were further separated as pure enantiomers. Structures together with absolute configurations were established by extensive spectroscopic analysis, as well as quantum chemistry calculations on ECD and optical rotations. Compounds 1-4 are rare meroterpenoids featuring a seco-phenyl group, while 1 and 2 possessed a novel 6-6/5 fused ring system. Compounds 1-4, 8, 11, and 12 showed antifungal activity against four plant pathogens with MIC values of 8-128 μg/mL. It is suggested that the meroterpenoids produced by T. crotocinigenum may play an important role in the antifungal property of the fungus, thereby protecting the host plant, i.e., potato.

Characterization of the complete chloroplast genome of a well-known Chinese medicinal herb, Scrophularia ningpoensis

Scrophularia ningpoensis has been used as a famous traditional medicinal herb in Asian countries to treat jaundice, dysentery, and the pain of rheumatism. In this paper, the complete chloroplast (cp) genome sequence of S. ningpoensis was reported and characterized. The cp genome is 153,175 bp in length, composed of a pair of 25,490 bp inverted repeat (IR) regions separated by a large single copy (LSC) region of 84,257 bp and a small single copy (SSC) region of 17,938 bp. There were 130 predicted genes (85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes) in the genome, and the overall GC content of the genome is 38%. Phylogenetic analysis based on the cp genome data showed that S. ningpoensis was sister to S. buergeriana.

The complete plastid genome of Iris domestica: a traditional Chinese medicine

Iris domestica has been used as Chinese traditional medicine to treat inflammation and throat disorders for many centuries. In this study, the complete plastid genome of I. domestica was first reported and characterized. The complete plastid genome is a typical quadripartite circular molecule of 153,729 bp in length, including a large single copy (LSC) region of 83,136 bp and a small single copy (SSC) region of 18,165 bp separated by two inverted repeat (IR) regions of 26,214 bp. A total of 132 genes including 86 protein-coding genes, 38 tRNA genes, and eight rRNA genes were identified. The phylogenetic analysis revealed that I. domestica was closer to I. gatesii.

Characterization of the complete chloroplast genome of Paederia scandens (Rubiaceae): a Chinese folk medicinal plant

Paederia scandens has been used as a traditional medicine in Asian countries to treat jaundice, dysentery, and the pain of rheumatism. The complete chloroplast (cp) genome sequence of P. scandens was reported and characterized in this study. The cp genome is 153,626 bp in length, composed of a pair of 26,513 bp inverted repeat (IR) regions separated by a large single-copy (LSC) region of 83,712 bp and a small single-copy (SSC) region of 16,888 bp. There were 131 predicted genes (86 protein-coding genes, 37 tRNA genes, and 8 rRNA genes) in the genome, and the overall GC content of the genome is 37.7%. Phylogenetic analysis based on the cp genome data showed that P. scandens was sister to the clade formed by Galium mollugo and G. aparine.

Anti-phytopathogenic sesquiterpenoid-xanthone adducts from potato endophytic fungus Bipolaris eleusines

Two sativene sesquiterpenoid-xanthone adducts from potato endophytic fungus Bipolaris eleusines

Curtachalasins, immunosuppressive agents from the endophytic fungus Xylaria cf. curta

Eleven new cytochalasins were isolated from Xylaria cf. curta. Their selective immunosuppressive properties provide new clues for drug development of immunosuppressants.

Trichothecrotocins A-C, Antiphytopathogenic Agents from Potato Endophytic Fungus Trichothecium crotocinigenum

Two trichothecene sesquiterpenoids, trichothecrotocins A (1) and B (2), and a merosesquiterpenoid racemate, (±)-trichothecrotocin C (3), were obtained from potato endophytic fungus Trichothecium crotocinigenum by bioguided isolation. Their structures were elucidated by extensive spectroscopic methods, electronic circular dichroism calculations, and single-crystal X-ray diffraction. Compounds 1 and 2 are trichothecenes possessing new ring systems. Compound 3 possesses a novel 6/6-5/5/5 fused ring system. Compounds 1-3 showed antiphytopathogenic activities with MIC values of 8-128 μg/mL.

Anti-bacterial chromones from cultures of the endophytic fungus Bipolaris eleusines

One previously undescribed chromone (S)-5-hydroxyl-2-(1-hydroxyethyl)-7-methylchromone (1) and one known analogue (2), as well as four known sativene-type sesquiterpenoids bipolenins A‒C (3‒5), were isolated from cultures of the endophytic fungus Bipolaris eleusines. Their structure were elucidated by extensive spectroscopic methods and the data comparison with those reported in the literature. Compounds 1 and 2 showed weak inhibitory activities against Staphylococcus aureus subsp. aureus with the inhibition rates of 56.3 ± 0.48 and 32 ± 1.27%, respectively, at the concentration of 128 μg/mL.

Polyellisin, a novel polyketide from cultures of the basidiomycete Polyporus ellisii

Polyellisin (1), an unprecedented polyketide possessing a tricyclic system sharing a spiroketal carbon, was isolated from cultures of the basidiomycete Polyporus ellisii. The structure with absolute configuration was elucidated by means of spectroscopic methods and the single crystal X-ray diffraction. Polyellisin showed NO production inhibition with an IC₅₀ value of 17.2 μM.

Polyellisin (1), an unprecedented polyketide possessing a tricyclic system sharing a spiroketal carbon, was isolated from cultures of the basidiomycete Polyporus ellisii.

Nicotabin A, a Sesquiterpenoid Derivative from Nicotiana tabacum

Nicotabin A (1), a sesquiterpenoid derivative possessing a fused 5/6/5/5/5 ring system, was isolated from leaves of Nicotiana tabacum. The structure was elucidated by extensive spectroscopic methods and confirmed by single crystal X-ray diffraction. The plausible biosynthetic pathway for 1 was proposed. Compound 1 inhibited nitric oxide production in LPS-activated RAW264.7 macrophages with an IC50 of 22.1 μM.

Seco-sativene and Seco-longifolene Sesquiterpenoids from Cultures of Endophytic Fungus Bipolaris eleusines

Two new seco-sativene sesquiterpenoids, bipolenins D (1) and E (2), a new seco-longifolene sesquiterpenoid, bipolenin F (3), together with three known analogues (4-6), were obtained from cultures of endophytic fungus Bipolaris eleusines. Their structures were established by MS and NMR data. Compounds 1-6 showed no activity to five human cancer cell lines.

Two new phenolic compounds and antitumor activities of asparinin A from Asparagus officinalis

Two new phenolic acid compounds, asparoffin C (1) and asparoffin D (2), together with four known compounds, asparenyol (3), gobicusin B (4), 1-methoxy-2-hydroxy-4-[5-(4-hydroxyphenoxy)-3-penten-1-ynyl] phenol (5), and asparinin A (6), have been isolated from the stems of Asparagus officinalis. The structures were established by extensive spectroscopic methods (MS and 1D and 2D NMR). Compound 6 has obvious antitumor activities both in vitro and in vivo.

Two new acetylenic compounds from Asparagus officinalis

Two new acetylenic compounds, asparoffins A (1) and B (2), together with two known compounds, nyasol (3) and 3″-methoxynyasol (4), were isolated from stems of Asparagus officinalis. The structures of two new compounds were elucidated on the basis of detailed spectroscopic analyses (UV, IR, MS, 1D, and 2D NMR). All compounds were evaluated for their cytotoxicities against three human cancer cell lines.

Three New Triterpenoids from European Mushroom Tricholoma terreum

Three rare triterpenoids, saponaceolides Q-S (1-3), have been isolated from fruiting bodies of the mushroom Tricholoma terreum. Their structures were characterized based on extensive spectroscopic data. Compound 1 showed certain cytotoxicities against four human tumor cell lines.

Three new sativene sesquiterpenoids from cultures of endophytic fungus Bipolaris eleusines

Three new sativene sesquiterpenoids, bipolenins A-C (1-3), together with two known analogs (4 and 5), were obtained from cultures of endophytic fungus Bipolaris eleusines. The structures of new compounds were elucidated on the basis of extensive spectroscopic analyses. Compound 2 showed weak inhibitory activities against lung cancer A-549 and breast cancer MCF-7 with IC50 values of 33.2 and 19.1 μmol, respectively.

Four new C18-diterpenoid alkaloids with analgesic activity from Aconitum weixiense

Four new C18-diterpenoid alkaloids, weisaconitines A-D (1-4), were isolated from Aconitum weixiense. Based on extensive UV, IR, MS, 1D and 2D NMR analyses, their structures were elucidated as 8-O-ethyldolaconine (1), 4-demethylgenicunine B (2), 14-oxoaconosine (3), and 8-O-ethylaconosine (4). The analgesic activity of compound 4 was studied with CH3COOH-induced writhing model in mice. Compound 4 showed writhing inhibitions of 24% (50 mg/kg), 26% (100 mg/kg) and 34% (200 mg/kg), respectively, as compared to the reference drug aspirin (63%) at a dose of 200 mg/kg.

Two new compounds from an endophytic fungus Alternaria solani

Two new secondary metabolites, named 7-dehydroxyl-zinniol (1) and 20-hydroxyl-ergosta-4,6,8(14),22-tetraen-3-one (2), were isolated from the culture of Alternaria solani, an endophytic fungal strain residing in the roots of Aconitum transsectum. Their structures were elucidated on the basis of comprehensive spectroscopic analyses including IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR. Biological activity tests indicated that compound 1 showed moderate anti-HBV activity.

Two new C19-diterpenoid alkaloids from Aconitum transsectum

Two new C(19)-diterpenoid alkaloids, named aconitramines D (1) and E (2), were isolated from the roots of Aconitum transsectum. Based on comprehensive spectroscopic analyses including IR, ESI-MS, HR-ESI-MS, and 1D and 2D NMR, their structures were elucidated as 18-demethoxyltransconitine A (1) and 8-O-anisoyl-14-hydroxylacoforesticine (2).