Use of mushrooms as antioxidants in a lipid oxidation model under indirect and direct oxidation tests: ethanolic extracts of Ganoderma resinaceum and Phlebopus bruchii

BACKGROUND

Foods contain lipids that are easily susceptible to oxidation, which can modify their sensory properties. Although these compounds provide characteristic flavours and odours, there are also unwanted compounds, such as volatile secondary oxidation products, representing a recurring problem for both the industry and consumers. Synthetic antioxidants are often employed to prevent this but their chronic consumption can be detrimental to human health. The present study evaluates the antioxidant potential of ethanolic extracts from Ganoderma resinaceum and Phlebopus bruchii using an accelerated oxidation test.

RESULTS

The composition profile of the extracts was investigated, identifying the presence of tryptophan, quinic acid, caffeic acid and 3,4-dihydroxyphenylglycol-phenolic acid. The antioxidant capacity of the extracts was compared with that of butylated hydroxytoluene (BHT) in sunflower oil that was oven-heated at 60 °C. Chemical (peroxide value, p-anisidine value and conjugated dienes) and volatile (2-octenal, 2-heptenal and 2,4-decadienal) indicators were measured over 28 days. The peroxide value decreased for both extracts at a similar level to that of BHT 0.02% w/w, and conjugate dienes decreased in the presence of G. resinaceum 0.1% w/w. Meanwhile, p-anisidine exhibited a slightly greater decrease for P. bruchii 0.1% w/w than for BHT. The sample with 0.1% w/w of extracts showed a reduction in volatile secondary oxidation compounds, indicating significant antioxidant activity.

CONCLUSION

Based on these results, both extracts could be proposed as potential antioxidants in foods with a high lipid content. © 2024 Society of Chemical Industry.

Network pharmacology-based analysis of Resinacein S against non-alcoholic fatty liver disease by modulating lipid metabolism

Background

Ganoderma lucidum is reportedly the best source of traditional natural bioactive constituents. Ganoderma triterpenoids (GTs) have been verified as an alternative adjuvant for treating leukemia, cancer, hepatitis and diabetes. One of the major triterpenoids, Resinacein S, has been found to regulate lipid metabolism and mitochondrial biogenesis. Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease that has become a major public health problem. Given the regulatory effects on lipid metabolism of Resinacein S, we sought to explore potential protective effects against NAFLD.

Methods

Resinacein S was extracted and isolated from G. lucidum. And mice were fed with high fat diet with or without Resinacein S to detect hepatic steatosis. According to Network Pharmacology and RNA-seq, we analyzed the hub genes of Resinacein S against NAFLD disease.

Results

Our results can be summarized as follows: (1) The structure of Resinacein S was elucidated using NMR and MS methods. (2) Resinacein S treatment could significantly attenuate high-fat diet (HFD)-induced hepatic steatosis and hepatic lipid accumulation in mouse. (3) GO terms, KEGG pathways and the PPI network of Resinacein S induced Differentially Expressed Genes (DEGs) demonstrated the key target genes of Resinacein S against NAFLD. (4) The hub proteins in PPI network analysis could be used for NAFLD diagnosis and treatment as drug targets.

Conclusion

Resinacein S can significantly change the lipid metabolism in liver cells and yield a protective effect against steatosis and liver injury. Intersected proteins between NAFLD related genes and Resinacein S-induced DEGs, especially the hub protein in PPI network analysis, can be used to characterize targets of Resinacein S against NAFLD.

Triterpenoids and meroterpenoids from the edible Ganoderma resinaceum and their potential anti-inflammatory, antioxidant and anti-apoptosis activities

Ganoderma resinaceum, as a traditional edible mushroom, has been widely reported to improve neurodegenerative diseases characterized by oxidative stress and inflammation. In this study, five new terpenoids, including four lanostane triterpenoids, named ganoresinoid A-D (1-4) and one meroterpenoid, named ganoresinoid E (5), along with 27 known compounds (6-32), were isolated from the fruiting bodies of edible mushroom G. resinaceum. These structures were identified by NMR, HRESIMS data analysis. All metabolites were evaluated for anti-inflammatory, antioxidative and anti-apoptosis activities. Among them, ganoresinoid A showed notably restrained nitric oxide (NO), IL-1β, IL-6 and TNF-α levels in LPS-activated BV-2 microglial cells via suppressing TLR-4/ NF-κB and MAPK signaling pathway. Simultaneously, ganoresinoid A remarkably alleviated LPS-induced apoptosis by means of the decrease of mitochondrial membrane potential (MMP) and reactive oxygen species (ROS). In addition, ganoresinoid A demonstrated antioxidant effects in H₂O₂-induced SH-SY5Y cells by activating the Akt/GSK-3β/Nrf2 signaling pathway. Taken together, these results may provide a stronger theoretical basis for ganoresinoid A from G. resinaceum as nutrition intervention to alleviate neurodegenerative diseases.

Polysaccharides from Basidiocarps of the Polypore Fungus Ganoderma resinaceum: Isolation and Structure

In this study, we focused on the isolation and structural characterization of polysaccharides from a basidiocarp of polypore fungus Ganoderma resinaceum. Polysaccharide fractions were obtained by successive extractions with cold water at room temperature (20 °C), hot water under reflux (100 °C), and a solution of 1 mol L-1 sodium hydroxide. The purity of all fractions was controlled mainly by Fourier transform infrared (FTIR) spectroscopy, and their composition and structure were characterized by organic elemental analysis; neutral sugar and methylation analyses by gas chromatography equipped with flame ionization detector (GC/FID) and mass spectrometry detector (GC/MS), respectively; and by correlation nuclear magnetic resonance (NMR) spectroscopy. The aqueous extracts contained two main polysaccharides identified as a branched O-2-β-d-mannosyl-(1→6)-α-d-galactan and a highly branched (1→3)(1→4)(1→6)-β-d-glucan. Mannogalactan predominated in the cold water extract, and β-d-glucan was the main product of the hot water extract. The hot water soluble fraction was further separated by preparative anion exchange chromatography into three sub-fractions; two of them were identified as branched β-d-glucans with a structure similar to the corresponding polysaccharide of the original fraction. The alkaline extract contained a linear (1→3)-α-d-glucan and a weakly branched (1→3)-β-d-glucan having terminal β-d-glucosyl residues attached to O-6 of the backbone. The insoluble part after all extractions was identified as a polysaccharide complex containing chitin and β-d-glucans.

Waste Rose Flower and Lavender Straw Biomass-An Innovative Lignocellulose Feedstock for Mycelium Bio-Materials Development Using Newly Isolated Ganoderma resinaceum GA1M

In this study, for the first time, the potential of rose flowers and lavender straw waste biomass was studied as feeding lignocellulose substrates for the cultivation of newly isolated in Bulgaria Ganoderma resinaceum GA1M with the objective of obtaining mycelium-based bio-composites. The chemical characterization and Fourier Transform Infrared (FTIR) spectroscopy established that the proximate composition of steam distilled lavender straw (SDLS) and hexane extracted rose flowers (HERF) was a serious prerequisite supporting the self-growth of mycelium bio-materials with improved antibacterial and aromatic properties. The basic physico-mechanical properties of the developed bio-composites were determined. The apparent density of the mycelium HERF-based bio-composites (462 kg/m³) was higher than that of the SDLS-based bio-composite (347 kg/m³) and both were much denser than expanded polystyren (EPS), lighter than medium-density fiber board (MDF) and oriented strand board (OSB) and similar to hempcrete. The preliminary testing of their compressive behavior revealed that the compressive resistance of SDLS-based bio-composite was 718 kPa, while for HERF-based bio-composite it was 1029 kPa and both values are similar to the compressive strength of hempcrete with similar apparent density. Water absorbance analysis showed, that both mycelium HERF- and SDLS-based bio-composites were hydrophilic and further investigations are needed to limit the hydrophilicity of the lignocellulose fibers, to tune the density and to improve compressive resistance.

A new lanostane triterpenoid from Ganoderma resinaceum

A new 23,24,25,26,27-five-nortriterpenoid (1), named resinacein T, was isolated from an ethanol extract of the fruiting bodies in Ganoderma resinaceum of family Ganodermataceae, together with two known lanostane triterpenoids, 3β,7β,15α,24-tetrahydroxy-11,23-dioxo-lanost-8-en-26-oic acid (2), and resinacein O (3). The structures of compounds (1-3) were elucidated using NMR and MS methods.

NMR-based Structural Classification, Identification, and Quantification of Triterpenoids from Edible Mushroom Ganoderma resinaceum

Ganoderma mushrooms have been widely used as functional food in China, Japan, and Korea. Ganoderma triterpenoids are deemed to be the main functional constituents. The structures of Ganoderma triterpenoids are complex but quite similar, which makes their analyses markedly limited. In this study, we developed a general 2D NMR method to differentiate Ganoderma triterpenoids, which classifies them into six types (A-F). Then, by the NMR-based isolation of A-F type triterpenoids from the fruiting bodies of G. resinaceum, four new compounds (1-4) and eight known compounds (5-12) were obtained. Moreover, combined with spiking experiments in 1D and 2D NMR spectra, compounds 5, 7, and 8, which belong to triterpenoids of A and B types, were identified. At the end, to achieve a more extensive application for this NMR method, a qNMR method for the absolute quantification of 5, 7, and 8 in the gross triterpenoids from G. resinaceum was set up. The results showed that this NMR method is reliable for the NMR-guided isolation and quantification of triterpenoids in G. resinaceum.

Isolation, Structural Elucidation, and α-Glucosidase Inhibitory Activities of Triterpenoid Lactones and Their Relevant Biogenetic Constituents from Ganoderma resinaceum

Ganoderma resinaceum has been used as an ethnomedicine for lowering blood sugar. To clarify the bioactive chemical constituents contributing to lower blood sugar, chemical investigation on the fruiting bodies of Ganoderma resinaceum was conducted by chromatographic techniques, and led to the isolation of 14 compounds. Their structures were elucidated as triterpenoid lactones (1–4 and 8) and ganoderma acids (5–7 and 9–14) based on the analysis of extensive spectroscopy (mass spectrometry (MS), nuclear magnetic resonance (NMR), infrared (IR), and ultraviolet (UV)) and comparison with literature data. Compounds 3, 5, 6, and 9–14 were evaluated for α-glucosidase inhibitory activity. Compounds 1–7 are new compounds. Compounds 1–4 and 8 were characteristic of an oxaspirolactone moiety, consisting of a five-membered ether ring, a five-membered lactone ring, and a characteristic C-23 spiro carbon. It is rare for natural products that such an oxaspirolactone moiety occurred in the lanostane-type triterpenoids. Compounds 5–7 and 9–14 may be important intermediates of the biosynthetic pathways of 1–4 and 8. Compounds 1 and 2 showed more potent inhibitory activity against α-glucosidase compared with the positive control drug acarbose with IC₅₀ value of 0.75 ± 0.018 mM and 1.64 ± 0.022 mM, respectively.

Lanostane triterpenes from the mushroom Ganoderma resinaceum and their inhibitory activities against α-glucosidase

Eighteen previously undescribed lanostane triterpenes and thirty known analogues were obtained from the fruiting bodies of Ganoderma resinaceum. Resinacein C was isolated from a natural source for the first time. The structures of all the above compounds were elucidated by extensive spectroscopic analysis and comparisons of their spectroscopic data with those reported in the literature. Furthermore, in an in vitro assay, Resinacein C, ganoderic acid Y, lucialdehyde C, 7-oxo-ganoderic acid Z₃, 7-oxo-ganoderic acid Z, and lucidadiol showed strong inhibitory effects against α-glucosidase compared with the positive control drug acarbose. The structure-activity relationships of ganoderma triterpenes on α-glucosidase inhibition showed that the C-24/C-25 double bond is necessary for α-glucosidase inhibitory activity. Moreover, the carboxylic acid group at C-26 and the hydroxy group at C-15 play important roles in enhancing inhibitory effects of these triterpenes.

A new nortriterpenoid and an ergostane-type steroid from the fruiting bodies of the fungus Ganoderma resinaceum

One new expoxy nortriterpenoid (1) and one new ergostane-type steroid (2), together with seven known steroids (3-9), were obtained from the fruiting bodies of the fungus Ganoderma resinaceum. The new compounds were elucidated on the basis of extensive spectroscopic data (MS, NMR, IR, and UV) and the known compounds were identified by comparing spectroscopic data with those reported in literature.

Nortriterpenoids from the Fruiting Bodies of the Mushroom Ganoderma resinaceum

Ganoderma resinaceum is usually used as ethnomedicine for immune-regulation, hyperglycemia, and liver disease. To date, only a few chemical constituents have been reported from G. resinaceum. In this study, fifteen nortriterpenoids including six new nortriterpenoids (1–6) and nine known analogs (7–15), were separated and purified from the fruiting bodies of G. resinaceum. New compounds were identified as lucidone I (1), lucidone J (2), lucidone K (3), lucidone I (4), ganosineniol B (5), and ganosineniol C (6), based on analysis of extensive spectroscopic data (high resolution mass spectrometry (HRMS), nuclear magnetic resonance (NMR), infrared (IR), and ultraviolet (UV)). The known compounds were assigned as lucidone A (7), lucidone B (8), lucidone H (9), lucidone E (10), lucidone F (11), lucidone D (12), lucidone C (13), ganoderense F (14), and ganosineniol A (15), by comparing their spectroscopic data with those reported in the literature. Compounds 3, 4, and 7–13 were examined for α-glucosidase inhibitory activity and display no significant activity, but the finding may support that the side chain of ganoderma triterpenoids played an important role in α-glucosidase inhibitory activity.

Response of the Higher Basidiomycetic Ganoderma resinaceum to Sodium Chloride Stress

Ganoderma resinaceum tolerated sodium chloride salt stress within a range of 0 mM till 300 mM. It responded to salt stress with fluctuation in proline formation at different NaCl concentrations. However,the mycelial dry weight,total protein contents and exopolysaccharides did not changed considerably. Increasing sodium chloride concentration led to morphological alteration in fungal mycelia with disappearance of fungal cell wall,plasmolysis,and vacuolation as indicated with electron microscopic examination of the fungal growth.