Chemical Constituents of the Culture Broth of Phellinus linteus and Their Antioxidant Activity.

The medicinal fungus Phellinus linteus, in the family Hymenochaetaceae, has been used as a traditional medicine for the treatment of various diseases. In this study, the chemical constituents of the culture broth of P. linteus were investigated. P. linteus was cultured in potato dextrose broth medium, and the culture broth was extracted with ethyl acetate. The ethyl acetate-soluble portion was concentrated and subjected to ODS column chromatography, followed by Sephadex LH-20 column chromatography. Six compounds (1~6) were purified by preparative reversed-phase high-performance liquid chromatography. Spectroscopic methods identified their structures as caffeic acid (1), inotilone (2), 4-(3,4-dihydroxyphenyl)-3-buten-2-one (3), phellilane H (4), (2E,4E)-(+)-4'-hydroxy-γ-ionylideneacetic acid (5), and (2E,4E)-γ-ionylideneacetic acid (6). Compounds 1, 2, and 3 exhibited potent dose-dependent antioxidant activity.

Neuraminidase Inhibitors from the Fermentation Broth of Phellinus linteus.

During a search for neuraminidase inhibitors derived from medicinal fungi, we found that the fermentation broth of Phellinus linteus exhibited potent neuraminidase inhibitory activity. Through bioassay-guided fractionation, two active compounds were purified from the ethyl acetate-soluble portion of the fermentation broth of P. linteus. These structures were identified as inotilone (1) and 4-(3,4-dihydroxyphenyl)-3-buten-2-one (2) by spectroscopic methods. Compounds 1 and 2 inhibited H1N1 neuraminidase activity with IC50 values of 29.1 and 125.6 µM, respectively, in a dose-dependent manner. They also exhibited an antiviral effect in a viral cytopathic effect reduction assay using MDCK cells. These results suggest that compounds 1 and 2 from the culture broth of P. linteus would be good candidates for the prevention and therapeutic strategies towards viral infections.

Characterization of an antihypertensive angiotensin I-converting enzyme inhibitory peptide from the edible mushroom Hypsizygus marmoreus.

Hypertension is one of the very serious diseases and, recently, hypertensive patient longevity has been increased significantly. Therefore, the development of new antihypertensive drugs or bioactive compounds is very important to remedy or prevent hypertension. The antihypertensive angiotensin I-converting enzyme (ACE) inhibitor in water extracts from the brown-cultivar-fruiting-body of Hypsizygus marmoreus was purified with ultrafiltration, C18 solid phase extraction chromatography and reverse-phase HPLC, and the purified ACE inhibitor with inhibitory activity of IC50 value of 0.19 mg/mL was obtained. The purified ACE inhibitor was found to be a new oligopeptide with the sequence LSMGSASLSP. Its molecular weight was estimated to be 567.3 Da and the water extracts containing ACE inhibitor from Hypsizygus marmoreus showed a clear antihypertensive action a spontaneously hypertensive rat.

Characterization of Species of Cladobotryum which Cause Cobweb Disease in Edible Mushrooms Grown in Korea.

Four Cladobotryum isolates were collected from four different commercially grown mushroom types infected with cobweb disease in Cheongdo-gun and Chilgok-gun of Gyeongbuk Province, Korea in 2010. The isolates were identified as C. mycophilum from Agaricus bisporus and Pleurotus eryngii, C. varium from Flammulina velutipes and Hypsizygus marmoreus. The cultural characteristics of the four isolates were investigated using potato dextrose agar (PDA) media under nine different temperatures ranging from 5~32℃. Rapid growth of the isolates to colony diameters of 47~82 mm was observed at conditions of 18~22℃. No growth was observed at 32℃. C. mycophilum produced a yellowish red pigment while C. varium produced a cream colored pigment after cultivation for 25 days on PDA. Phylogenetic analysis of the internal transcribed spacer region and partial 28S rDNA from the four isolates confirmed they were C. mycophilum and C. varium. Cross pathogenicity tests revealed that the two isolates of C. mycophilum were highly pathogenic toward three mushroom types, but not toward H. marmoreus. The two isolates of C. varium were less pathogenic than those of C. mycophilum, but were pathogenic toward all mushroom types evaluated.

Mechanism of anti-platelet activity of Oligoporus tephroleucus oligoporin A: involvement of extracellular signal-regulated kinase phosphorylation and cyclic nucleotide elevation.

This study investigated the inhibitory effects of oligoporin A on platelet aggregation and the mechanism of its action on downstream signaling molecules. Oligoporin A was isolated from the fruiting bodies of Oligoporus tephroleucus (Polyporaceae). The anti-platelet activities of oligoporin A were studied using rat platelets. The effects of oligoporin A on intracellular Ca(2+) mobilization, ATP release, production of the cyclic nucleotides cAMP and cGMP, extracellular signal-regulated kinase (ERK) 2 phosphorylation, and fibrinogen binding to active integrin α(II)(b)ß(3) were assessed. Oligoporin A, but not oligoporins B and C, inhibited collagen-induced platelet aggregation in a concentration-dependent manner. Interestingly, oligoporin A did not affect ADP- and thrombin-induced platelet aggregations, which act on different types of membrane receptors. Granule secretion analysis demonstrated that oligoporin A significantly and dose-dependently reduced collagen-induced ATP release and intracellular Ca(2+) mobilization. Additionally, oligoporin A induced the dynamic increase in cAMP and cGMP. Increased cGMP production was further confirmed by the simultaneous production of nitric oxide. Pretreatment with oligoporin A significantly blocked collagen-induced ERK2 phosphorylation. Finally, oligoporin A vaguely diminished the binding of fibrinogen to its cognate receptor, integrin α(II)(b)ß(3). The results indicate that oligoporin A inhibits only collagen-induced platelet aggregation mediated through the modulation of downstream signaling molecules. Oligoporin A may be beneficial against cardiovascular disease provoked by aberrant platelet activation.

Phellinins A1 and A2, new styrylpyrones from the culture broth of Phellinus sp. KACC93057P: I. Fermentation, taxonomy, isolation and biological properties.

Novel styrylpyrones, phellinins A1 and A2, were isolated together with known styrylpyrone compounds, hispidin and 1,1-distyrylpyrylethan, from the cultured broth of Phellinus sp. KACC93057P. These compounds were purified by solvent partition, Sephadex LH-20 column chromatography, C(18)-solid phase extraction and finally by reversed-phase (ODS) TLC. To identify the phellinin producer Phellinus sp. KACC93057P, the ribosomal DNA (rDNA) internal transcribed space regions containing 5.8 rDNA were sequenced and compared with those of the known Phellinus isolates. Phellinus sp. KACC93057P was 94.8% identical to P. baumii and P. linteus, all of which did not produce phellinins A1 and A2. These compounds significantly scavenged free radicals such as 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) and superoxide.

Inhibitory mechanisms of dihydroginsenoside Rg3 in platelet aggregation: critical roles of ERK2 and cAMP.

Ginsenoside Rg3, a single ginseng saponin, is known to be a major anti-platelet component of protopanaxadiol that is isolated from Korean red ginseng. In this study, we investigated whether dihydroginsenoside Rg3, a stable chemical derivative of ginsenoside Rg3, also demonstrated anti-platelet activity. Dihydroginsenoside Rg3 inhibited thrombin-induced platelet aggregation in a concentration-dependent manner with an IC50 (concentration producing 50% inhibition) of 18.8 +/- 0.4 microM. Ginsenoside Rg3 inhibited platelet aggregation which was induced by thrombin (0.1 U mL(-1)) with an IC50 of 40.2 +/- 0.9 microM. We next determined whether dihydroginsenoside Rg3 affected different types of ligand-induced platelet aggregation. We found that dihydroginsenoside Rg3 inhibited collagen-induced platelet aggregation with an IC50 of 20.0 +/- 0.9 microM. To elucidate the inhibitory mechanism of dihydroginsenoside Rg3 on aggregation, we analysed its downstream signalling pathway. It was interesting to note that dihydroginsenoside Rg3 elevated cyclic AMP production in resting platelets, but did not affect cyclic GMP production. In addition, we found that dihydroginsenoside Rg3 potently suppressed phosphorylation of extracellular signal-regulated kinase 2 (ERK2), which was stimulated by collagen (2.5 microg mL(-1)), but not of p38 mitogen-activated protein kinase. Taken together, our results indicate that dihydroginsenoside Rg3 potently inhibited platelet aggregation via the modulation of downstream signalling components such as cAMP and ERK2.

Screening and Optimal Extraction of a New Antidementia ß-Secretase Inhibitor-Containing Mushroom.

To produce a potent antidementia ß-secretase inhibitor from a mushroom, the ß-secretase inhibitory activities of various mushroom extracts were determined. Methanol extracts of Lentinula edodes exhibited the highest inhibitory activity (40.1%). The inhibitor was maximally extracted when a fruiting body of L. edodes was treated with 50% methanol at 40℃ for 24 h.

Effect of Various Sawdusts and Logs Media on the Fruiting Body Formation of Phellinus gilvus.

Present experiments were conducted to determine the possibility of artificial culture with various sawdust of P. gilvus. The pH value was 6.0 of oak sawdust, 6.5 of mulberry sawdust, 6.6 of elm sawdust, 6.3 of acacia sawdust and 6.1 of apple tree sawdust. Mycelial density on elm sawdust and acacia sawdust were lower than those of oak sawdust, and apple sawdust. Weight of fresh fruiting body showed that 179 g on oak tree, 227 g on oak sawdust, 21 g on elm tree, 76 g on elm sawdust, 106 g on apple tree, and 170 g on apple sawdust. Among them, the yield of oak substrates was the highest whereas acacia sawdust was the lowest, and it is concluded that the yields of sawdust substrates were higher than log substrates. P. gilvus grown on various sawdusts and logs used in this study have shown similar in anti-tumor activity against P388.

The Culture Conditions for the Mycelial Growth of Phellinus spp.

Phellinus genus belonged to Hymenochaetaceae of Basidiomycetes and has been well known as one of the most popular medicinal mushrooms due to high antitumor activity. This study was carried out to obtain the basic information for mycelial culture conditions of Phellinus linteus, P. baumii, and P. gilvus. According to colony diameter and mycelial density, the media for suitable mycelial growth of them were shown in MEA, glucose peptone, and MCM. The optimum temperature for mycelial growth was 30℃. Carbon and nitrogen sources were mannose and malt extract, respectively. The optimum C/N ratio was 10 : 1 to 5: 1 with 2% glucose concentration, vitamin was thiamine-HCl, organic acid was succinic acid, and mineral salt was MgSO4·7H2O.