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Research background. Tiger milk mushroom (Lignosus rhinocerus) is a medicinal mushroom that is geographically distributed in the region of South China, Thailand, Malaysia, Indonesia, Philippines and Papua New Guinea. Consumption of its sclerotium has been reported to treat various ailments. However, its anticancer potential towards oral cancer cell lines is yet to be determined considering the traditional method of its consumption by biting/chewing of the sclerotium. Experimental approach. Mushroom sclerotial powder of cultivar TM02® was extracted and fractionated in a chromatographic column prior to cytotoxicity testing against a panel of human oral cancer cell lines. The capability of the identified bioactive fraction in regulating several molecules associated with its tumour necrosis factor (TNF) pathway was investigated. Results and conclusions. 2,5-Diphenyl-2H-tetrazolium bromide (MTT) proliferation assay indicated that cell lines ORL-48 (derived from gingiva), ORL-188 (derived from the tongue) and ORL-204 (derived from buccal mucosa) were inhibited by cold water extract of L. rhinocerus sclerotia and its high-molecular-mass fraction (HMM) in varying degrees with ORL-204 being most affected. Hence, the treatment of ORL-204 with HMM mushroom extract was further investigated. HMM mushroom extract induced apoptosis and G0/G1 phase cell cycle arrest through caspase-3/7 cleavage. Activities of MIP2 and COX-2 were downregulated by 0.2- and 4.6-fold respectively in the HMM mushroom extract-treated ORL-204 cells. Novelty and scientific contribution. Using ORL-204, we showed that HMM mushroom extract may act via the TNF pathway at various network sites as a potential dietary compound for cancer prevention and natural adjunct therapeutic to conventional cancer treatment., Pozadina istraživanja. Medicinska gljiva Lignosus rhinocerus rasprostranjena je na području južne Kine, Tajlanda, Malezije, Indonezije, Filipina i Papua Nove Gvineje. Sklerocij gljive koristi se za liječenje različitih oboljenja. Međutim, dosad još nije ispitan antikacerogeni učinak sklerocija ove medicinske gljive, koja se tradicionalno konzumira tako da se grize odnosno žvače, na stanice karcinoma usne šupljine. Eksperimentalni pristup. Ekstrakt praha sklerocija kultivara gljive TM02® frakcioniran je pomoću kromatografske kolone, te je zatim ispitan njegov citokosični učinak na različite stanične linije humanih karcinoma usne šupljine. Ispitana je sposobnost bioaktivne frakcije da regulira molekule koje sudjeluju u sintezi faktora nekroze tumora (TNF). Rezultati i zaključci. Ispitivanjem proliferacije stanica pomoću testa redukcije 2,5-difenil-2H-tetrazolijeva bromida (MTT) utvrđeno je da ekstrakt sklerocija L. rhinocerus dobiven hladnom vodom, i to frakcija velike molekulske mase, u različitoj mjeri inhibira rast staničnih linija ORL-48 (izoliranih iz desni), ORL-188 (izoliranih ih jezika), a ponajviše onih linije ORL-204 (izoliranih iz sluznice obraza). Stoga smo dodatno istražili učinak ekstrakta gljive velike molekulske mase na staničnu liniju ORL-204. Ektrakt je potaknuo apoptozu i zaustavio stanični ciklus u fazi G0/G1 cijepanjem kaspaze 3/7. U stanicama ORL-204 tretiranim ekstraktom gljive velike molekulske mase smanjila se aktivnost enzima MIP2 za 0,2 puta, a enzima COX-2 za 4,6 puta. Novina i znanstveni doprinos. Pomoću stanične linije ORL-204 pokazali smo da ekstrakt medicinske gljive velike molekulske mase može djelovati na sintezu faktora nekroze tumora, te se upotrijebiti kao prirodni dodatak prehrani za prevenciju razvoja karcinoma ili kao dodatak konvencionalnom liječenju karcinoma.

Research background. Ophiocordyceps sinensis, a highly valued medicinal fungus, is close to extinction due to overexploitation. Successful cultivation of O. sinensis fruiting body (OCS02®) shows that the cultivar has a promising nutritional value and numerous bioactive compounds. Antioxidant and antiproliferative properties and biologically active proteins of the OCS02® are investigated for possible development into nutraceuticals. Experimental approach. The chemical composition of the OCS02® cold water extract was determined, and the antioxidant activities were examined using ferric reducing, DPPH• and O2•- scavenging assays. Tetrazolium dye (MTT) cytotoxic assay was performed to assess the antiproliferative activity of the extract. Bioactive proteins in the active fraction of the extract were identified using liquid chromatography (LC) and tandem-mass spectrometry (MS/MS). Results and conclusions. The OCS02® extract exhibited strong O2•- scavenging (expressed as Trolox equivalents (18.4±1.1) mol/g) and potent cytotoxic activities against adenocarcinomic human alveolar basal epithelial (A549) cells (IC50=(58.2±6.8) µg/mL). High molecular mass polysaccharides, proteins and protein-polysaccharide complexes could have contributed to the antioxidant and cytotoxic selectivity of the OCS02®. LC-MS/MS analysis identified several potential cytotoxic proteases and an oxalate decarboxylase protein which may exhibit protection effects on kidneys. Novelty and scientific contribution. The findings demonstrate the potential of OCS02® to be developed into functional food due to its promising superoxide anion radical scavenging capacity, cytotoxic effect and presence of biopharmaceutically active proteins., Pozadina istraživanja. Vrlo cijenjena medicinska gljiva Ophiocordyceps sinensis je na rubu izumiranja zbog njezine prekomjerne eksploatacije. Uspješnim uzgojem plodišta gljive O. sinensis (OCS02®) potvrđeno je da taj kultivar ima obećavajuća hranjiva svojstva te sadržava brojne bioaktivne spojeve. Ispitana su njegova antioksidacijska i antiproliferacijska svojstva te sastav biološki aktivnih proteina, s ciljem mogućeg razvoja nutraceutika. Eksperimentalni pristup. Utvrđen je kemijski sastav ekstrakta gljive u hladnoj vodi, a antioksidacijska je aktivnost ispitana pomoću FRAP metode te metodama uklanjanja DPPH˙ i O2 radikala. Citotoksičnost odnosno antiproliferacijska aktivnost ekstrakta ispitana je testom na osnovi tetrazolija (MTT test). Bioaktivni proteini su identificirani u aktivnoj frakciji ekstrakta pomoću tekućinske kromatografije i tandemske spektrometrije masa. Rezultati i zaključci. Ekstrakt gljive OCS02® imao je izrazito jako svojstvo uklanjanja superoksid radikala (izraženo u ekvivalentima Troloxa (18,4±1,1) mol/g) i snažan citotoksični učinak (IC50=(58,2±6,8) µg/mL) na humane epitelne stanice adenokarcinoma pluća (A549). Moguće je da polisaharidi, proteini i kompleksi proteina s polisaharidima velike molekularne mase pridonose antioksidacijskoj i citotoksičnoj selektivnosti gljive OCS02®. Tekućinskom kromatografijom i tandemskom spektrometrijom masa identificirano je nekoliko potencijalno citotoksičnih proteaza te protein oksalat dekarboksilaza koji bi mogli imati zaštitni učinak na bubrege. Novina i znanstveni doprinos. Dobiveni rezultati pokazuju da se gljiva OCS02® može upotrijebiti u proizvodnji funkcionalne hrane zbog njezine obećavajuće sposobnosti uklanjanja superoksidnih aniona, citotoksičnog učinka te prisutnosti biofarmaceutski aktivnih proteina.

Background Genome mining facilitated by heterologous systems is an emerging approach to access the chemical diversity encoded in basidiomycete genomes. In this study, three sesquiterpene synthase genes, GME3634, GME3638, and GME9210, which were highly expressed in the sclerotium of the medicinal mushroom Lignosus rhinocerotis, were cloned and heterologously expressed in a yeast system. Results Metabolite profile analysis of the yeast culture extracts by GC–MS showed the production of several sesquiterpene alcohols (C15H26O), including cadinols and germacrene D-4-ol as major products. Other detected sesquiterpenes include selina-6-en-4-ol, β-elemene, β-cubebene, and cedrene. Two purified major compounds namely (+)-torreyol and α-cadinol synthesised by GME3638 and GME3634 respectively, are stereoisomers and their chemical structures were confirmed by 1H and 13C NMR. Phylogenetic analysis revealed that GME3638 and GME3634 are a pair of orthologues, and are grouped together with terpene synthases that synthesise cadinenes and related sesquiterpenes. (+)-Torreyol and α-cadinol were tested against a panel of human cancer cell lines and the latter was found to exhibit selective potent cytotoxicity in breast adenocarcinoma cells (MCF7) with IC50 value of 3.5 ± 0.58 μg/ml while α-cadinol is less active (IC50 = 18.0 ± 3.27 μg/ml). Conclusions This demonstrates that yeast-based genome mining, guided by transcriptomics, is a promising approach for uncovering bioactive compounds from medicinal mushrooms. Electronic supplementary material The online version of this article (doi:10.1186/s12934-017-0713-x) contains supplementary material, which is available to authorized users.