A benzofuran glycoside and an acetylenic acid from the fungus Laetiporus sulphureus var. miniatus

Inaoside A: New antioxidant phenolic compound from the edible mushroom Laetiporus cremeiporus

Laetiporus cremeiporus is the edible mushroom distributed in East Asia. It has been reported that an extract of L. cremeiporus exhibited DPPH radical scavenging activity. The aim of this study is to identify the antioxidant compound from L. cremeiporus. Guided by DPPH radical scavenging activity, a new antioxidant phenolic compound inaoside A (1) and three well-known bioactive compounds 5'-S-methyl-5'-thioadenosine (MTA, 2), nicotinamide (3), and adenosine (4) were isolated from L. cremeiporus. An antioxidant compound was isolated from L. cremeiporus for the first time. This is the first report of the isolation of 1, 2, and 4 from L. cremeiporus. The structures were determined by one- and two-dimensional NMR spectroscopic analysis and chemical derivatization. The antioxidant activities of extracts, fractions, and isolated compounds were evaluated by a DPPH radical scavenging assay. Compound 1 exhibited significant DPPH radical scavenging activity (80 % inhibition at 100 μg/mL, IC50 79.9 μM, trolox equivalent antioxidant capacity (TEAC) = 0.36).

Natural and engineered xylosyl products from microbial source

Glycosylation is a prevalent post-modification found in natural products and has a significant impact on the structural diversity and activity variation of natural products. Glucosylation is the most common type of glycosylation, whereas xylosylation is relatively rare. Despite their unique chemical structures and beneficial activities, xylosylated natural products from microorganisms have received little attention. This review provides, for the first time, a comprehensive summary of 126 microbial-derived xylosylated natural products, including xylosyl-cyathane diterpenes, xylosylated triterpenes, xylosyl aromatic compounds, and others. Among these compounds, xylosyl-cyathane diterpenes represent the highest number of derivatives, followed by xylosylated triterpenes. Xylosyl compounds from bacterial sources have less defined structural profiles compared to those from fungi. The characterization of xylosyltransferase EriJ from Basidiomycota extended the structural diversity of xylosyl cyathane diterpenes. This work provides a valuable reference for the research and use of xylosyltransferase for drug discovery and synthetic chemistry. Further work is needed to explore the potential applications of microbial derived xylosyl compounds and to develop novel xylosyl transferases. With the deepening of genomic sequencing of medicinal fungi, more biosynthesis of bioactive xylosyl compounds is expected to be elucidated in the future.

The alkynyl-containing compounds from mushrooms and their biological activities

Mushrooms have been utilized by humans for thousands of years due to their medicinal and nutritional properties. They are a crucial natural source of bioactive secondary metabolites, and recent advancements have led to the isolation of several alkynyl-containing compounds with potential medicinal uses. Despite their relatively low abundance, naturally occurring alkynyl compounds have attracted considerable attention due to their high reactivity. Bioactivity studies have shown that alkynyl compounds exhibit significant biological and pharmacological activities, including antitumor, antibacterial, antifungal, insecticidal, phototoxic, HIV-inhibitory, and immunosuppressive properties. This review systematically compiles 213 alkynyl-containing bioactive compounds isolated from mushrooms since 1947 and summarizes their diverse biological activities, focusing mainly on cytotoxicity and anticancer effects. This review serves as a detailed and comprehensive reference for the chemical structures and bioactivity of alkynyl-containing secondary metabolites from mushrooms. Moreover, it provides theoretical support for the development of chemical constituents containing alkynyl compounds in mushrooms based on academic research and theory.

Bioactive components of Laetiporus species and their pharmacological effects

Laetiporus species are brown rot fungi belonging to the order Polyporales in the division Basidiomycota. These species produce a variety of metabolites and provide a great source of natural material for the screening of medicinally active natural products or their derivatives. This review summarizes the research progress on bioactive metabolites of Laetiporus species up to April 2022, including biological macromolecules, for instance, polysaccharides and lectins, as well as 80 reported small molecule chemical components (15 sterols, 29 triterpenes, 10 sesquiterpenes, 5 polyenes, 10 volatile compounds, and 11 other compounds). These metabolites exhibit antimicrobial, anticancer, antioxidant, hepatoprotective, anti-inflammatory, and antidiabetic activities. Genome mining predicted 23 terpene synthases, 7 polyketide synthases, and 9 non-ribosomal peptide synthases involved in bioactive metabolites biosynthesis, which were analyzed by antiSMASH in L. sulphureus genome. This review will provide a basis for the biosynthesis of active components in Laetiporus species and a reference for the research of medical precursors. KEY POINTS: • The mini-review summarized 80 secondary metabolites of Laetiporus spp. • The main pharmacological activities of Laetiporus spp. were summarized. • Biosynthetic genes of terpenoids, polyketides, and non-ribosomal peptides were also summarized.

Stimulation of insulin secretion by acetylenic fatty acids in insulinoma MIN6 cells through FFAR1

We examined whether the acetylenic fatty acids 6-octadecynoic acid (6-ODA) and 9-octadecynoic acid (9-ODA) perform as ligands for free fatty acid receptors of medium- and long-chain fatty acids FFAR1 and FFAR4, previously called GPR40 and GPR120, respectively. Phosphorylation of extracellular signal-regulated kinase (ERK)-1/2 was increased through FFAR1 but not through FFAR4 expressed in HEK 293 cells, suggesting that 6-ODA and 9-ODA function as an FFAR1 ligand, but not as an FFAR4 ligand. Activation of ERK in FFAR1-expressing HEK293 cells by 6-ODA and 9-ODA peaked at 10 min after stimulation followed by a slow decrease, similar to ERK activation by rosiglitazone, which peaked at 10 min after stimulation and lasted longer. Glucose-dependent production of insulin from MIN6 insulinoma cells was induced by 6-ODA and 9-ODA in an FFAR1-dependent manner. In this process, 6-ODA and 9-ODA stimulated the production of insulin not in the first phase that occurred within 10 min after stimulation but in the second phase. F-actin-remodeling that reflects insulin granule recruiting to the plasma membrane in the second phase of insulin secretion by 6-ODA and 9-ODA suggested that they have an FFAR1-dependent function in insulin secretion from MIN6 cells.

European medicinal polypores--a modern view on traditional uses

ETHNOPHARMACOLOGICAL RELEVANCE

In particular five polypore species, i.e. Laetiporus sulphureus, Fomes fomentarius, Fomitopsis pinicola, Piptoporus betulinus, and Laricifomes officinalis, have been widely used in central European folk medicines for the treatment of various diseases, e.g. dysmenorrhoea, haemorrhoids, bladder disorders, pyretic diseases, treatment of coughs, cancer, and rheumatism. Prehistoric artefacts going back to over 5000 years underline the long tradition of using polypores for various applications ranging from food or tinder material to medicinal-spiritual uses as witnessed by two polypore species found among items of Ötzi, the Iceman. The present paper reviews the traditional uses, phytochemistry, and biological activity of the five mentioned polypores.

MATERIALS AND METHODS

All available information on the selected polypore taxa used in traditional folk medicine was collected through evaluation of literature in libraries and searches in online databases using SciFinder and Web of Knowledge.

RESULTS

Mycochemical studies report the presence of many primary (e.g. polysaccharides) and secondary metabolites (e.g. triterpenes). Crude extracts and isolated compounds show a wide spectrum of biological properties, such as anti-inflammatory, cytotoxic, and antimicrobial activities.

CONCLUSIONS

The investigated polypores possess a longstanding ethnomycological tradition in Europe. Here, we compile biological results which highlight their therapeutic value. Moreover, this work provides a solid base for further investigations on a molecular level, both compound- and target-wise.

Bioactive acetylenic metabolites

This article focuses on anticancer, and other biological activities of acetylenic metabolites obtained from plants and fungi. Acetylenic compounds belong to a class of molecules containing triple bond(s). Naturally occurring acetylenics are of particular interest since many of them display important biological activities and possess antitumor, antibacterial, antimicrobial, antifungal, and immunosuppressive properties. There are of great interest for medicine, pharmacology, medicinal chemistry, and pharmaceutical industries. This review presents structures and describes cytotoxic activities of more than 100 acetylenic metabolites, including fatty alcohols, ketones, and acids, acetylenic cyclohexanoids, spiroketal enol ethers, and carotenoids isolated from fungi and plants.

Yellow pigments, fomitellanols A and B, and drimane sesquiterpenoids, cryptoporic acids P and Q, from Fomitella fraxinea and their inhibitory activity against COX and 5-LO

Yellow pigments, fomitellanols A (1a) and B (2a), and drimane-type sesquiterpenoid ethers of isocitric acid, cryptoporic acids P (3) and Q (4), have been isolated from the fruiting bodies of Fomitella fraxinea (Polyporaceae). Their structures were established by a combination of extensive NMR spectroscopy and/or X-ray crystallographic analyses, and their biological activity against COX-1, COX-2, and 5-LO was investigated.

Laetirobin from the parasitic growth of Laetiporus sulphureus on Robinia pseudoacacia

(+/-)-Laetirobin (1) was isolated as a cytostatic lead from Laetiporus sulphureus growing parasitically on the black locust tree, Robinia pseudoacacia, by virtue of a reverse-immunoaffinity system. Using an LC/MS procedure, milligram quantities of (+/-)-laetirobin (1) were obtained, and the structure of 1 was elucidated by X-ray crystallography and confirmed by NMR spectroscopy. Preliminary cellular studies indicated that (+/-)-laetirobin (1) rapidly enters in tumor cells, blocks cell division at a late stage of mitosis, and invokes apoptosis.

Biosynthesis and function of polyacetylenes and allied natural products

Polyacetylenic natural products are a substantial class of often unstable compounds containing a unique carbon-carbon triple bond functionality, that are intriguing for their wide variety of biochemical and ecological functions, economic potential, and surprising mode of biosynthesis. Isotopic tracer experiments between 1960 and 1990 demonstrated that the majority of these compounds are derived from fatty acid and polyketide precursors. During the past decade, research into the metabolism of polyacetylenes has swiftly advanced, driven by the cloning of the first genes responsible for polyacetylene biosynthesis in plants, moss, fungi, and actinomycetes and the initial characterization of the gene products. The current state of knowledge of the biochemistry and molecular genetics of polyacetylenic secondary metabolic pathways will be presented together with an up-to-date survey of new terrestrial and marine natural products, their known biological activities, and a discussion of their likely metabolic origins.

N-Phenethylhexadecanamide from the edible mushroom Laetiporus sulphureus

N-Phenethylhexadecanamide was isolated from the MeOH extract of the fruiting bodies of the mushroom Laetiporus sulphureus together with eburicoic acid. Their structures were elucidated by spectroscopic methods.

Matrix Metalloproteinase-1 Inhibitor from the Stem Bark of Styrax japonica S. et Z

A bioassay-guided fractionation of the ethyl acetate soluble fraction from the stem bark of Styrax japonica S. et Z. (Styracaceae) yielded two new lignan compounds, styraxjaponoside A (1) and styraxjaponoside B (2), along with three known compounds, matairesinoside (3), egonol glucoside (4), and dihydrodehydrodiconiferyl alcohol 9'-O-glucoside (5). The structures of compounds 1-5 were determined by spectroscopic method, as well as 1D- and 2D-NMR (HSQC, 1H-1H COSY, and HMBC) spectroscopy. Among them, compound 2 exhibited potent inhibitory activity against matrix metalloproteinase (MMP)-1, and prevented the UV-induced changes in the MMP-1 expression. In addition, compounds 3 and 5 were isolated from this plant for the first time.

Two new steroidal derivatives from the fruit body of Chlorophyllum molybdites

Two new steroid derivatives, (22E,24R)-3alpha-ureido-ergosta-4,6,8(14),22-tetraene (1) and (22E,24R)-5alpha,8alpha-epidioxyergosta-6,9,22-triene-3beta-ol 3-O-beta-D-glucopyranoside (2) were isolated from the fruit bodies of Chlorophyllum molybdites (Agaricaceae). The structures were established by spectroscopic and chemical methods. These compounds exhibited cytotoxicity against Kato III cells.