Identifikacija bioaktivnih proteina gljive Ophiocordyceps sinensis i određivanje njihovog antioksidacijskog i citotoksičnog učinka pomoću shotgun analize proteoma

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

Medicinska gljiva Lignosus rhinocerus svojim imunomodulacijskim učinkom i reguliranjem signalnog puta posredovanog faktorom nekroze tumora uzrokuje apoptozu i zaustavlja stanični ciklus stanica karcinoma usne šupljine ORL-204

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

Heterologous expression of cytotoxic sesquiterpenoids from the medicinal mushroom Lignosus rhinocerotis in yeast

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 mushroomsH-YYY is supported by an Australian Awards Endeavour Research Fellowship. MJM-G received an Australian Awards Endeavour Scholarship and a Mexican CONACYT scholarship. YH-C is supported by an Australian Research Council Future Fellowship (FT160100233). This work was partially supported by Funda‑ mental Research Grant Scheme (FRGS): FP029-2014A from Ministry of Science, Technology and Innovation, Malaysia, and Postgraduate Research Grant (PPP): PG144/2014B from University of Malaya

Variable Carbon Catabolism among Salmonella enterica Serovar Typhi Isolates

BACKGROUND: Salmonella enterica serovar Typhi (S. Typhi) is strictly a human intracellular pathogen. It causes acute systemic (typhoid fever) and chronic infections that result in long-term asymptomatic human carriage. S. Typhi displays diverse disease manifestations in human infection and exhibits high clonality. The principal factors underlying the unique lifestyle of S. Typhi in its human host during acute and chronic infections remain largely unknown and are therefore the main objective of this study. METHODOLOGY/PRINCIPAL FINDINGS: To obtain insight into the intracellular lifestyle of S. Typhi, a high-throughput phenotypic microarray was employed to characterise the catabolic capacity of 190 carbon sources in S. Typhi strains. The success of this study lies in the carefully selected library of S. Typhi strains, including strains from two geographically distinct areas of typhoid endemicity, an asymptomatic human carrier, clinical stools and blood samples and sewage-contaminated rivers. An extremely low carbon catabolic capacity (27% of 190 carbon substrates) was observed among the strains. The carbon catabolic profiles appeared to suggest that S. Typhi strains survived well on carbon subtrates that are found abundantly in the human body but not in others. The strains could not utilise plant-associated carbon substrates. In addition, α-glycerolphosphate, glycerol, L-serine, pyruvate and lactate served as better carbon sources to monosaccharides in the S. Typhi strains tested. CONCLUSION: The carbon catabolic profiles suggest that S. Typhi could survive and persist well in the nutrient depleted metabolic niches in the human host but not in the environment outside of the host. These findings serve as caveats for future studies to understand how carbon catabolism relates to the pathogenesis and transmission of this pathogen

Heterologous expression of cytotoxic sesquiterpenoids from the medicinal mushroom Lignosus rhinocerotis in yeast

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 (C 15 H 26 O), including cadinols and germacrene D-4-ol as major products. Other detected sesquiterpenes include selina-6-en-4-ol, ß-elemene, ß-cubebene, and cedrene. Two purified major compounds namely (+)-torreyol and a-cadinol synthesised by GME3638 and GME3634 respectively, are stereoisomers and their chemical structures were confirmed by 1 H and 13 C 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 a-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 IC 50 value of 3.5 ± 0.58 µg/ml while a-cadinol is less active (IC 50 = 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

Environmental assessment schemes for non-domestic building refurbishment in the Malaysian context

The increase in global warming, energy consumption and greenhouse gas emissions has gained attention in various regions. In Malaysia, the government announced a voluntary commitment to reduce 40% of CO 2 emissions by 2020 and to refurbish 100 government buildings. Existing buildings make a large contribution to energy consumption and CO 2 emissions, therefore refurbishing existing buildings is an essential strategy to achieve the commitment. There is no single assessment scheme for building refurbishment in Malaysia and hence, this study aims to develop a comprehensive list of assessment themes and sub-themes for building refurbishment purposes. It examines and compares 10 assessment schemes from various countries: BREEAM, LEED, CASBEE, BEAM Plus, GBLS, Green Star, HQE, Green Mark, GBI and MyCrest. The findings revealed fourteen themes that were considered for assessment: management, sustainable site, transport, indoor environmental quality (IEQ), water, waste, material, energy, pollution, innovation, economic, social, culture and quality of services. Energy and IEQ are dominant themes in all assessment schemes. Most of the schemes are considered relatively weak in evaluating economic and social aspects, in comparison to environmental aspects. The assessment of quality of services is overlooked in most of the schemes, including GBI and MyCrest in Malaysia. Outcomes from this paper will form the baseline for a new environmental assessment scheme that aimed at non-domestic building refurbishments in Malaysia. A new model is proposed for the development of an environmental assessment scheme in the further stage

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Toxicological and biopharmacological investigations of tiger milk mushroom-Lignosus tigris / Kong Boon Hong

The traditional use for the sclerotium of Tiger Milk mushroom (Lignosus spp.) by local Malaysian natives as a cure for a variety of illnesses has been well documented and scientifically validated. Lignosus tigris C.S. Tan, a species of the Tiger Milk mushroom, has been identified recently and successfully cultivated. In the present study, the potential toxicity of the cultivated L. tigris E sclerotia was evaluated using Sprague Dawley (SD) rats in 14-day acute and 28-day sub-acute toxicity studies. Acute toxicity study showed that the sclerotial powder at a single dose of 2000 mg/kg did not cause adverse effects on growth rate, neither hematological and biochemical parameters, nor pathological changes in vital organ tissues. In addition, daily administration of L. tigris E sclerotial powder at three different doses of 250, 500 and 1000 mg/kg for 28 consecutive days did not cause any treatment-related toxicity in the SD rats, as evidenced by the body weight, general behavior, hematological, clinical biochemical, relative organ weights, and histopathological examination on the vital and reproductive organs. Therefore, the noobserved-adverse-effect level (NOAEL) dose for sub-acute toxicity of the L. tigris E sclerotial powder is more than 1000 mg/kg. The nutritional value, chemical composition, antioxidant and cytotoxic activities of the L. tigris E sclerotium were also investigated. The L. tigris E sclerotium is rich in carbohydrate and protein with moderate amounts of dietary fibers and contains nine essential amino acids. The cold water extract (CWE) of the sclerotial powder showed potent antioxidant activity and cytotoxic selectivity on human breast adenocarcinoma (MCF7) cells. Further fractionation of the CWE using Sephadex G-50 chromatography followed by ammonium sulfate precipitation showed iv that the cytotoxic activity of the mushroom extract against MCF7 cells is contributed mainly by the high molecular weight proteins (HMW-P). HMW-P showed selective cytotoxicity against MCF7 cells (IC50 value = 1.17 ± 0.47 µg/mL) through induction of apoptosis mediated by both intrinsic and extrinsic pathways as indicated by an increase in caspase-8 and -9 activities as well as a decrease of Bcl-2 and increase of Bax expression levels. The intraperitoneal administration of HMW-P (5 µg/g of body weight) to mice bearing MCF7 solid tumor successfully suppressed the tumor growth. HMW-P induced cell death in the tumor via apoptosis as high number of apoptotic cells (stained with TUNEL) was detected in the tumor tissue of the treated mice. Mice treated with HMWP, however, showed a significant reduction in body weight but no pathological changes were observed in the vital organs. Separation of proteins of HMW-P on SDS-PAGE followed by LC-MS/MS analysis identified several potential cytotoxic proteins including lectins, serine proteases and a deoxyribonuclease-like protein. L. tigris E deoxyribonuclease-like protein (LTED) was purified from HMW-P using an affinity chromatography and it exhibited selective cytotoxicity against MCF7 cells (IC50 value = 6.57 ± 0.61 µg/mL) through induction of apoptosis. LTED-induced apoptosis occurs probably via the activation of caspase-dependent and caspase-independent pathways as evidenced by an increase in the activities of caspase 3/7, -8 and -9, a decrease of Bcl-2 protein expression and increases in Bax, AIF and endoG protein expressions. These results showed that there is a great potential to develop L. tigris E sclerotia into functional food and as a nutraceutical, as well as a source of novel proteins with therapeutic applications

Sub-acute Toxicity Study of Tiger Milk Mushroom Lignosus tigris Chon S. Tan Cultivar E Sclerotium in Sprague Dawley Rats

Lignosus also known as Tiger Milk Mushroom, is classified in the family Polyporaceae and mainly consumed for its medicinal properties in Southeast Asia and China. The sclerotium is known as the part with medicinal value and often used by the natives to treat a variety of ailments. Lignosus tigris Chon S. Tan, one of the species of the Malaysia Tiger Milk mushroom, has recently been successfully cultivated in laboratory. Earlier studies have demonstrated the L. tigris cultivar E sclerotia exhibited beneficial biomedicinal properties. This study evaluated the potential toxicity of L. tigris E sclerotia in a 28-day sub-acute oral administration in Sprague Dawley (SD) rats. L. tigris E sclerotial powder was administered orally at three different doses of 250, 500 and 1000 mg/kg to the SD rats once daily, consecutively for 28 days. Body weight of the rats was recorded and general behavior, adverse effects and mortality were observed daily throughout the experimental period. At the end of the experiment, blood hematology and biochemistry, relative organ weights and histopathological analysis were performed. Results showed that there were no mortality nor signs of toxicity throughout the 28-day sub-acute toxicity study. Oral administration of the L. tigris E sclerotial powder at daily dose up to 1000 mg/kg had no significant effects in body weight, relative organ weight, blood hematological and biochemistry, gross pathology and histopathology of the organs. L. tigris E sclerotial powder did not cause any treatment-related adverse effect in the rats at different treatment dosages up to 1000 mg/kg. As the lethal dose for the rats is above 1000 mg/kg, the no-observed-adverse-effect level (NOAEL) dose is more than 1000 mg/kg

Antimicrobial Susceptibility Profiling and Genomic Diversity of Multidrug-Resistant Acinetobacter baumannii Isolates from a Teaching Hospital in Malaysia

The resistance phenotypes and genomic diversity of 185 Acinetobacter baumannii isolates obtained from the intensive care unit (ICU) of a local teaching hospital in Kuala Lumpur from 2006 to 2009 were determined using antimicrobial susceptibility testing and pulsed-field gel electrophoresis (PFGE). Antibiogram analyses showed that the isolates were fully resistant to β-lactam antimicrobials and had high resistance rates to the other antimicrobial agents tested. However, the isolates were susceptible to polymyxin B. Resistance to cefoperazone/sulbactam was only detected in strains isolated from 2007 to 2009. Some environmental isolates and an isolate from the hands of a healthcare worker (HCW) had identical resistance profiles and PFGE profiles that were closely related to patient isolates. Cluster analyses based on the PFGE profiles showed there was a persistent clone of endemic isolates in the ICU environment. The transmission route from HCWs to fomites to patients, which caused a long-term infection in the ICU of the University Malaya Medical Centre, was observed in this study. These data provide a better understanding of A. baumannii epidemiology within the hospital and the possible transmission routes. Knowledge of changes in the resistance rates of A. baumannii in our local hospital will improve antimicrobial therapy