Ganodermin, an antifungal protein from fruiting bodies of the medicinal mushroom Ganoderma lucidum

Three new lanostanoid triterpenes from the fruiting bodies of Ganoderma tropicum

Three new lanostanoid triterpenes, 3β,7β,15β-trihydroxy-11,23-dioxo-lanost-8,16-dien-26-oic acid (1), 3β,7β,15β-trihydroxy-11,23-dioxo-lanost-8,16-dien-26-oic acid methyl ester (2), and 3β,15β-dihydroxy-7,11,23-trioxo-lanost-8,16-dien-26-oic acid methyl ester (3) were isolated from the EtOAc extract of the fruiting bodies of Ganoderma tropicum. Their structures were elucidated on the basis of 1D and 2D NMR spectroscopy as well as MS. The bioassay of inhibitory activity against acetylcholinesterase (AChE) of these isolates was evaluated and compound 2 exhibited definite inhibitory activity against AChE.

Sacchachitin, a novel chitin-polysaccharide conjugate macromolecule present in Ganoderma lucidum: purification, composition, and properties

CONTEXT

The extraction method and the crude wound healing effects of sacchachitin from Ganoderma tsugae Murr. (Ganodermataceae) has been cited. However, its purity is still largely limited.

OBJECTIVE

An improvement of the fractionation protocol to purify the sacchachitin from Ganoderma lucidum L. (Ganodermataceae) (SGL) is needed.

METHODS

Fruiting bodies were extracted with double distilled water and subsequently the residue treated with 95% ethanol and then 40% ethanol. After being filtered, the pH of the supernatant was adjusted to 4.0 with 1 N HCl and lyophilized. The supernatant was added (3:1 v/v) ethanol, the precipitate was collected, 2% NaOH was added and refluxed. The supernatant was collected with pH adjusted to 4.0, then treated with 10% potassium hydroxide (KOH) with repeating acid precipitation and (3:1) ethanol precipitation twice more to obtain the sacchachitin.

RESULTS

SGL had a hexosamine content 16.3% (w/w), firmly linked to a talomannan. Its Fourier Transform Infrared Spectroscopy (FTIR) spectrum revealed specific absorption (in cm(-1)) ν(O-H) 3455.5 b,s, amide ν(C=O) 1678.5, and amide I° δ(N-H) 1550.4. The percentage deacetylation degree was 37.6 and 39.4% for SGL and MSC, respectively. As contrast, MSC contained only 6.6% of hexosamine with a low protein/carbohydrate ratio 0.35 comparing to 0.82 for SGL. SGL was only moderately strong antioxidant regarding the anti-DPPH, antihydroxyl free radical, and antisuperoxide anion capabilities, exhibiting an IC(33) values of 10 mg/mL (the highest scavenging capability never exceeding 33%), 0.9 mg/mL, and 4.8 mg/mL, respectively.

CONCLUSION

We have successfully isolated the pure sacchachitin from the fruiting bodies of G. lucidum that exhibits potent antioxidative activity and may be useful in fabrication of the artificial skin composite substitute.

The development and application of a multiple gene co-silencing system using endogenous URA3 as a reporter gene in Ganoderma lucidum

Ganoderma lucidum is one of the most important medicinal mushrooms; however, molecular genetics research on this species has been limited due to a lack of reliable reverse genetic tools. In this study, the endogenous orotidine 5′-monophosphate decarboxylase gene (URA3) was cloned as a silencing reporter, and four gene-silencing methods using hairpin, sense, antisense, and dual promoter constructs, were introduced into G. lucidum through a simple electroporation procedure. A comparison and evaluation of silencing efficiency demonstrated that all of the four methods differentially suppressed the expression of URA3. Our data unequivocally indicate that the dual promoter silencing vector yields the highest rate of URA3 silencing compared with other vectors (up to 81.9%). To highlight the advantages of the dual promoter system, we constructed a co-silencing system based on the dual promoter method and succeeded in co-silencing URA3 and laccase in G. lucidum. The reduction of the mRNA levels of the two genes were correlated. Thus, the screening efficiency for RNAi knockdown of multiple genes may be improved by the co-silencing of an endogenous reporter gene. The molecular tools developed in this study should facilitate the isolation of genes and the characterization of the functions of multiple genes in this pharmaceutically important species, and these tools should be highly useful for the study of other basidiomycetes.

Comparative SELDI-TOF-MS profiling of low-molecular-mass proteins from Lignosus rhinocerus (Cooke) Ryvarden grown under stirred and static conditions of liquid fermentation

Mushrooms are considered as important source of biologically active compounds which include low-molecular-mass protein/peptides (LMMP). In this study, we attempted to profile the LMMP from Lignosus rhinocerus, a wild medicinal mushroom, grown by static cultures (SC) and in stirred tank reactor (STR). Crude water extract (CWE) and protein fractions were profiled using H50 ProteinChip® arrays and SELDI-TOF-MS. Three protein peaks of 5.8, 6.9 and 9.1 kDa were found to be common to spectra of L. rhinocerus CWE from both culture conditions. Partial protein purification has resulted in detection of more peaks in the spectra of protein fractions. For protein fractions of L. rhinocerus cultured in STR, most peaks were observed in the range of 3-8 kDa whereas some peaks with molecular mass up to 14.3 kDa were noted in spectra of protein fractions from SC. Our results have demonstrated the optimization of profiling method using SELDI-TOF-MS for fungal LMMP.

A laccase with antiproliferative activity against tumor cells from an edible mushroom, white common Agrocybe cylindracea

A laccase, with HIV-1 reverse transcriptase inhibitory activity (IC(50)=12.7 μM) and antiproliferative activity against HepG2 cells (IC(50)=5.6 μM) and MCF7 cells (IC(50)=6.5 μM), was purified from fresh fruiting bodies of the edible white common Agrocybe cylindracea mushroom. The laccase, which had a novel N-terminal sequence, displayed a molecular mass of 58 kDa within the range reported for most other mushroom laccases. The purification protocol entailed ion exchange chromatography on DEAE-cellulose, SP-Sepharose, and Q-Sepharose and gel filtration on Superdex 75. The laccase was adsorbed on DEAE-cellulose and Q-Sepharose, but unadsorbed on SP-Sepharose. Its optimum pH was pH 3-4 and its optimum temperature was 50°C. The activity of the isolated laccase differed from one substrate to another. The ranking was ABTS>N,N-dimethyl-1,4-phenylenediamine>hydroquinone>catechol>2-methylcatechol>pyrogallol.

Cordymin, an antifungal peptide from the medicinal fungus Cordyceps militaris

Cordymin, an antifungal peptide with a molecular mass of 10,906 Da and an N-terminal amino acid sequence distinct from those of previously reported proteins, was purified from the medicinal mushroom Cordyceps militaris. The isolation protocol comprised ion exchange chromatography of the aqueous extract on SP-Sepharose and Mono S and gel filtration on Superdex 75 by a fast protein liquid chromatography system. Cordymin was adsorbed on both cation exchangers. The peptide inhibited mycelial growth in Bipolaris maydis, Mycosphaerella arachidicola, Rhizoctonia solani and Candida albicans with an IC(50) of 50 μM, 10 μM, 80 μM, and 0.75 mM, respectively. However, there was no effect on Aspergillus fumigatus, Fusarium oxysporum and Valsa mali when tested up to 2 mM. The antifungal activity of the peptide was stable up to 100°C and in the pH range 6-13, and unaffected by 10 mM Zn(2+) and 10 mM Mg(2+). Cordymin inhibited HIV-1 reverse transcriptase with an IC(50) of 55 μM. Cordymin displayed antiproliferative activity toward breast cancer cells (MCF-7) but there was no effect on colon cancer cells (HT-29). There was no mitogenic activity toward mouse spleen cells and no nitric oxide inducing activity toward mouse macrophages when tested up to 1 mM.

First report of an antifungal amidase from Peltophorum pterocarpum. [corrected]

A 60 kDa antifungal amidase was purified from Peltophorum pterocarpum [corrected] seeds using an isolation procedure that entailed ion-exchange chromatography on Q-Sepharose, ion-exchange chromatography on DEAE-cellulose and FPLC-gel filtration on Superdex 75. Unlike most other antifungal proteins isolated previously, it was adsorbed on Q-Sepharose and DEAE-cellulose. The isolated protein, designated as peltopterin, exhibited an N-terminal amino acid sequence closely resembling those of amidases. It exhibited amidase activity and digested iodoacetamide with an optimum pH and temperature at pH 9 and 50 degrees C, respectively. It also hydrolyzed acrylamide and urea. It impeded mycelial growth in Rhizotonia solani with an IC(50) of 0.65 microm. Chitin deposition at hyphal tips in R. solani was observed by staining with Congo red after incubation with peltopterin. Its antifungal activity was stable throughout pH 0-14 and 25-100 degrees C. It potently inhibited HIV-1 reverse transcriptase with an IC(50) of 27 nm.

Medicinal mushrooms: Towards a new horizon

The arising awareness about functional food has created a boom in this new millennium. Mushrooms are widely consumed by the people due to their nutritive and medicinal properties. Belonging to taxonomic category of basidiomycetes or ascomycetes, these mushrooms possess antioxidant and antimicrobial properties. They are also one of the richest source of anticancer and immunomodulating agents. Thus these novel myochemicals from these mushrooms are the wave of future.

Ganodermataceae: natural products and their related pharmacological functions

The objective of this paper is to review the natural products and the pharmacological functions of Ganodermataceae family. Presently, studies on the bioactive components of Lingzhi are focused on polysaccharides and triterpenes/triterpenoids compounds. New Ganoderma polysaccharides, including their molecular weights, glycosyl residue compositions, glycosyl linkage and branches, are summarized in this paper. Also presented are new types of triterpenes and their characteristics from Lingzhi. Taking Ganoderma lucidum as an example, we reviewed its pharmacological functions in anti-tumor and immune-modulating activities for treating hypoglycemosis, hepatoprotection, and the effect on blood vessel system. Based on the advances in Lingzhi research in the past few decades, both G. lucidum and G. sinense are considered as the representative species of medicinal mushroom Lingzhi in China. Until 2001, G. tsugae was only advised to be used as the materials of the health products. The biologically-active components related to pharmacological functions of these three species were studied more than other Ganodermataceae family species; however, which have been used in less modern folk medicine.

Structure elucidation and complete NMR spectral assignments of three new lanostanoid triterpenes with unprecedented Delta(16, 17) double bond from Ganoderma lucidum

Three new lanostanoid triterpenes named 3beta,7beta-di- hydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oic acid (1), 3beta,7beta-dihydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oic acid methyl ester (2), and 12beta-acetoxy-3beta,7beta-dihydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oic acid (3) were isolated from the fruit bodies of Ganoderma lucidum. They all show a Delta(16, 17) double bond unprecedented in such types of lanostanoid triterpenes possessing the side chain at C-17. The complete NMR assignments for these compounds were carried out using (1)H, (13)C, DEPT, COSY, HSQC, HMBC, and ROESY NMR experiments.

Ganoderma lucidum and its pharmaceutically active compounds

Ganoderma lucidum is a wood-degrading basidiomycete with numerous pharmacological effects. Since the mushroom is very rare in nature, artificial cultivation of fruiting bodies has been known on wood logs and on sawdust in plastic bags or bottles. Biotechnological cultivation of G. lucidum mycelia in bioreactors has also been established, both on solid substrates and in liquid media by submerged cultivation of fungal biomass. The most important pharmacologically active constituents of G. lucidum are triterpenoids and polysaccharides. Triterpenoids have been reported to possess hepatoprotective, anti-hypertensive, hypocholesterolemic and anti-histaminic effects, anti-tumor and anti-engiogenic activity, effects on platelet aggregation and complement inhibition. Polysaccharides, especially beta-d-glucans, have been known to possess anti-tumor effects through immunomodulation and anti-angiogenesis. In addition, polysaccharides have a protective effect against free radicals and reduce cell damage caused by mutagens.

Ganoderma - a therapeutic fungal biofactory

Ganoderma is a basidiomycete white rot fungus which has been used for medicinal purposes for centuries particularly in China, Japan and Korea. A great deal of work has been carried out on Ganoderma lucidum. The common names for preparations include Lingzhi, Munnertake, Sachitake, Reishi and Youngzhi. This review collates the publications detailing activities and compounds by representative species whilst considering the most valid claims of effectiveness. The biological activities reported of preparations from Ganoderma are remarkable and given most emphasis herein as distinct from structure/activity information. The metabolites consist of mainly polysaccharides and terpenoids. Many are activities against the major diseases of our time and so the present review is of great importance. The list of effects is huge ranging from anti-cancer to relieving blockages of the bladder. However, the reports have not all been tested scientifically with the convincing evidence is reserved for assays of pure compounds. It is a prime example of an ancient remedy being of great relevance to the modern era. There does appear to be an assumption that the therapeutic effects attributed to the fungus have been proven. The next step is to produce some effective medicines which may be hampered by problems of mass production.

A laccase from the medicinal mushroom Ganoderma lucidum

A protein demonstrating laccase activity and potent inhibitory activity towards human immunodeficiency virus (HIV)-1 reverse transcriptase (IC50 1.2 microM) was isolated from fresh fruiting bodies of the medicinal mushroom Ganoderma lucidum. The laccase had a novel N-terminal sequence and a molecular mass of 75 kDa, which is higher than the range (55-56 kDa) reported for most other mushroom laccases. It was isolated by sequential chromatography on DEAE-cellulose and Affi-gel blue gel and adsorption on Con A-Sepharose. Unlike some of the previously isolated laccases, it was adsorbed only on Con A-Sepharose. The enzyme required a pH of 3-5 and a temperature of 70 degrees C to exhibit maximal activity. Minimal activity was detected at pH 6 and 7. Activity was undetectable at pH 8 and 9 and after exposure to 100 degrees C for 10 min.