Submerged fermentation production and characterization of intracellular triterpenoids from Ganoderma lucidum using HPLC-ESI-MS

Chemodiversity, pharmacological activity, and biosynthesis of specialized metabolites from medicinal model fungi Ganoderma lucidum

Ganoderma lucidum is a precious fungus, particularly valued for its dual use as both medicine and food. Ganoderic acids (GAs), the distinctive triterpenoids found in the Ganoderma genus, exhibit a wide range of pharmacological activities. However, the limited resources of GAs restrict their clinic usage and drug discovery. In this review, we presented a comprehensive summary focusing on the diverse structures and pharmacological activity of GAs in G. lucidum. Additionally, we discussed the latest advancements in the elucidation of GA biosynthesis, as well as the progress in heterosynthesis and liquid fermentation methods aimed at further increasing GA production. Furthermore, we summarized the omics data, genetic transformation system, and cultivation techniques of G. lucidum, described as medicinal model fungi. The understanding of Ganoderic acids chemodiversity and biosynthesis in medicinal model fungi Ganoderma lucidum will provide important insights into the exploration and utilization of natural products in medicinal fungi.

Overview of fungal terpene synthases and their regulation

Terpenes and terpenoids are a group of isoprene-derived molecules that constitute the largest group of natural products and secondary metabolites produced by living things, with more than 25,000 compounds reported. These compounds are synthesized by enzymes called terpene synthases, which include several families of cyclases and enzymes. These are responsible for adding functional groups to cyclized structures. Fungal terpenoids are of great interest for their pharmacological properties; therefore, understanding the mechanisms that regulate their synthesis (regulation of the mevalonate pathway, regulation of gene expression, and availability of cofactors) is essential to direct their production. For this reason, this review addresses the detailed study of the biosynthesis of fungal terpenoids and their regulation by various physiological and environmental factors.

Identifying Bioactive Ingredients and Antioxidant Activities of Wild Sanghuangporus Species of Medicinal Fungi

Sanghuangporus refers to a group of rare medicinal fungi with remarkable therapeutic properties. However, current knowledge on the bioactive ingredients and antioxidant activities of different species of this genus is limited. In this study, a total of 15 wild strains from 8 species of Sanghuangporus were selected as the experimental materials for identification of the bioactive components (polysaccharide, polyphenol, flavonoid, triterpenoid, and ascorbic acid) and antioxidant activities (scavenging activities against hydroxyl, superoxide, DPPH, and ABTS radicals; superoxide dismutase activity; and ferric reducing ability of plasma). Notably, individual strains contained different levels of various indicators, among which Sanghuangporus baumii Cui 3573, S. sanghuang Cui 14419 and Cui 14441, S. vaninii Dai 9061, and S. zonatus Dai 10841 displayed the strongest activities. The correlation analysis of bioactive ingredients and antioxidant activities revealed that the antioxidant capacity of Sanghuangporus is mainly associated with the contents of flavonoid and ascorbic acid, followed by polyphenol and triterpenoid, and finally, polysaccharide. Together, the results obtained from the comprehensive and systematic comparative analyses contribute further potential resources and critical guidance for the separation, purification, and further development and utilization of bioactive agents from wild Sanghuangporus species, as well as the optimization of their artificial cultivation conditions.

Heme oxygenase-1/carbon monoxide signaling participates in the accumulation of triterpenoids of Ganoderma lucidum

Ganoderic triterpenoids (GTs) are the primary bioactive constituents of the Basidiomycotina fungus, Ganoderma lucidum. These compounds exhibit antitumor, anti-hyperlipidemic, and immune-modulatory pharmacological activities. This study focused on GT accumulation in mycelia of G. lucidum mediated by the heme oxygenase-1 (HO-1)/carbon monoxide (CO) signaling. Compared with the control, hemin (10 μmol/L) induced an increase of 60.1% in GT content and 57.1% in HO-1 activity. Moreover, carbon monoxide-releasing molecule-2 (CORM-2), CO donor, increased GT content by 56.0% and HO-1 activity by 18.1%. Zn protoporphyrin IX (ZnPPIX), a specific HO-1 inhibitor, significantly reduced GT content by 26.0% and HO-1 activity by 15.8%, while hemin supplementation reversed these effects. Transcriptome sequencing showed that HO-1/CO could function directly as a regulator involved in promoting GT accumulation by regulating gene expression in the mevalonate pathway, and modulating the reactive oxygen species (ROS) and Ca²⁺ pathways. The results of this study may help enhance large-scale GT production and support further exploration of GT metabolic networks and relevant signaling cross-talk.

High-Resolution QTOF-MRM for Highly Accurate Identification and Quantification of Trace Levels of Triterpenoids in Ganoderma lucidum Mycelium

The accurate quantification of triterpenoids in Ganoderma lucidum mushroom in the mycelium stage is challenging due to their low concentrations, interference from other possible isomers, and the complex matrix. Here, a high-resolution quadrupole-time-of-flight mass spectrometry "multiple reaction monitoring" with target enhancement (HR-QTOF-MRM) method was developed to quantify seven target triterpenoids in G. lucidum. The performance of this method was compared against an optimized QQQ-MRM method. The HR-QTOF-MRM was shown to be capable of distinguishing target triterpenoids from interferent peaks in the presence of matrices. The HR-QTOF-MRM LOD and LLOQ values were found to be one to two times lower than those derived from the QQQ-MRM method. Intraday and interday variabilities of the HR-QTOF-MRM demonstrated better reproducibility than the QQQ-MRM. In addition, excellent recoveries of the analytes ranging from 80 to 117% were achieved. Spiking experiments were carried out to verify and compare the quantitative accuracy of the two methods. The HR-QTOF-MRM method provided better percent accuracy, ranging from 84% to 99% (<3% RSD), compared with the range of 69 to 114% (<4%RSD) given by the QQQ-MRM method. These results demonstrate that the new HR-QTOF-MRM mode is able to improve sensitivity, reproducibility, and accuracy of trace level analysis of triterpenoids in the complex biological samples. The triterpenoid concentrations were in the range of nondetect to 0.06-6.72 mg/g of dried weight in fruiting body and to 0.0009-0.01 mg/g of dried weight in mycelium.

Purification and antioxidant and anti-Inflammatory activity of extracellular polysaccharopeptide from sanghuang mushroom, Sanghuangporus lonicericola

BACKGROUND

Sanghuang mushrooms are medicinal fungi widely used in eastern Asia. In this study, the antioxidant and anti-inflammatory activity of a novel extracellular polysaccharopeptide, sanghuang extracellular polysaccharopeptide (SePSP) was investigated. The SePSP was purified from the submerged fermentation broth of a sanghuang mycelium, Sanghuangporus lonicericola strain CBS17, which was isolated from a wild sanghuang fruiting body.

RESULTS

The SePSP was extracted using an ethanol precipitation procedure, followed by diethylaminoethanol (DEAE) anion-exchange and size-exclusion chromatography. The mass ratio of the polysaccharide and peptide components in the purified SePSP was approximately 4.87:1. By determining its free radical scavenging abilities using 2,2-diphenyl-1-picrylhydrazyl (DPPH), the hydroxyl free radical, and the superoxide anion free radical, as well as its total reducing power, SePSP was shown to have strong concentration-dependent antioxidant activity in vitro. Further, SePSP effectively alleviated dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) in mice. Administration of 200 mg kg^-1 SePSP by gavage for 7 days prevented body weight loss; significantly reduced the mRNA levels of proinflammatory cytokines, including TNF-α and IL-1β; increased mRNA level of the anti-inflammatory cytokine IL-10 in the colon, and decreased the malondialdehyde concentration from 6.42 to 4.82 μmol L^-1 in the blood in UC mice.

CONCLUSION

The SePSP had strong concentration-dependent antioxidant activity in vitro and effectively alleviated DSS-induced UC in mice. The in vivo therapeutic efficacy in DSS-induced UC may be mediated by modulating the expression of inflammatory cytokines and inhibiting oxidative stress. The findings provide a scientific rationale for the use of bioactive nutraceuticals from sanghuang mushrooms to develop functional foods for the prevention and treatment of UC. © 2020 Society of Chemical Industry.

Differentiation of black and white pitch (Burseraceae) oleoresins: A mass spectrometry-based chemoethnotaxonomic study

ETHNOPHARMACOLOGICAL RELEVANCE

In the quilombola communities of the municipality of Oriximiná (Pará State, Brazil), Protium spp. (Burseraceae) oleoresins are distinguished in black and white pitch. White pitch oleoresins may be superior to black pitch in terms of quality, but the criteria used for their differentiation are fairly subjective.

AIM OF THE STUDY

This study was designed to provide a scientific rationale for the traditional differentiation of black and white pitch oleoresins based on their non-volatile fraction.

MATERIALS AND METHODS

Black and white pitch oleoresin samples collected in quilombola territories in Oriximiná were analysed by GC-EI-MS and UPLC-APCI-MS. The feasibility of EI and APCI mass spectrometry-based pattern recognition methods PLS-DA and Random Forest Analysis (RFA) for black and white pitch oleoresins differentiation was demonstrated.

RESULTS

The UPLC-APCI-MS method allowed the separation of 43 triterpenoids. Assessment of the triterpenoid fingerprints by GC-EI-MS led to the tentative identification of ursa-9(11),12-dien-3-ol as a potential marker for black pitch oleoresins. PLS-DA and RFA applied to the APCI-MS and EI-MS data gave good models for black and white pitch oleoresins classification. The most important ions for the classifications of black pitch oleoresins by APCI-MS/PLS-DA and APCI-MS/RFA likely represented triterpenoid acids.

CONCLUSIONS

The triterpenoid pattern differs between black and white pitch oleoresins. The characteristic presence of ursa-9(11),12-dien-3-ol and triterpenoids acids in black pitch oleoresins, along with other field observations, suggest that black pitch oleoresins are actually aged white pitch oleoresins.

Apoptosis induction of colorectal cancer cells HTL-9 in vitro by the transformed products of soybean isoflavones by Ganoderma lucidum

Soybean isoflavones have been one of the potential preventive candidates for antitumor research in recent years. In this paper, we first studied the transformation of soybean isoflavones with the homogenized slurry of Ganoderma lucidum. The resultant transformed products (TSI) contained (703.21±4.35) mg/g of genistein, with transformed rates of 96.63% and 87.82% of daidzein and genistein, respectively, and TSI also could enrich the bioactive metabolites of G. lucidum. The antitumor effects of TSI on human colorectal cancer cell line HTL-9, human breast cancer cell line MCF-7, and human immortalized gastric epithelial cell line GES-1 were also studied. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay showed that TSI could dramatically reduce the viability rates of HTL-9 cells and MCF-7 cells without detectable cytotoxicity on GES-1 normal cells when the TSI concentration was lower than 100 μg/ml. With 100 μg/ml of TSI, HTL-9 cells were arrested in the G1 phase, and late-apoptosis was primarily induced, accompanied with partial early-apoptosis. TSI could induce primarily early-apoptosis by arresting cells in the G1 phase of MCF-7 cells. For HTL-9 cells, Western-blot and reverse-transcriptase polymerase chain reaction (RT-PCR) analysis showed that TSI (100 μg/ml) can up-regulate the expression of Bax, Caspase-3, Caspase-8, and cytochrome c (Cyto-c), indicating that TSI could induce cell apoptosis mainly through the mitochondrial pathway. In addition, the expression of p53 was up-regulated, while the expression of Survivin and nuclear factor κB (NF-κB) was down-regulated. All these results showed that TSI could induce apoptosis of HTL-9 cells by the regulation of multiple apoptosis-related genes.

Effects of Armillariella tabescens mycelia on the growth performance and intestinal immune response and microflora of early-weaned pigs

This study was performed to evaluate effects of Armillariella tabescens (A. tabescens) on the growth performance and intestinal immune response and microflora in early-weaned pigs when used as feed additive. A. tabescens mycelia were added to basal diets at concentrations of 0%, 0.1%, 0.3% or 0.9% (w/w). A total of 144 commercial cross-bred piglets were randomly allocated to one of these four diets and fed for 30 days. The growth performance of early-weaned piglets displayed improvement with diets containing 0.1% and 0.3% dried mycelia powder from A. tabescens. Supplementing with 0.1% or 0.3% A. tabescens mycelia induced a 2.6- and three-fold increase in secretory immunoglobulin A (sIgA) content in the jejunal mucosa, respectively, but had only a marginal effect on sIgA in the ileal mucosa. Expression of interleukin-2, interferon-γ, and tumor necrosis factor-α in the jejunal mucosa were elevated with A. tabescens mycelia administration. Increased amounts of Lactobacillus spp. and Bifidobacterium spp. in the jejunum, and decreased amounts of Escherichia coli in the jejunum and ileum were observed with the administration of A. tabescens-containing diets. This study demonstrated that A. tabescens had beneficial effects on the growth performance and intestinal microflora of early-weaned pigs.