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  1. Fulltext A pantropically introduced tree is followed by specific ectomycorrhizal symbionts due to pseudo-vertical transmission
    Séne S, Selosse MA, Forget M, Lambourdière J, Cissé K, Diédhiou AG, et al.
    ISME J, 2018 06;12(7):1806-1816.
    PMID: 29535364 DOI: 10.1038/s41396-018-0088-y
    Global trade increases plant introductions, but joint introduction of associated microbes is overlooked. We analyzed the ectomycorrhizal fungi of a Caribbean beach tree, seagrape (Coccoloba uvifera, Polygonacaeae), introduced pantropically to stabilize coastal soils and produce edible fruits. Seagrape displays a limited symbiont diversity in the Caribbean. In five regions of introduction (Brazil, Japan, Malaysia, Réunion and Senegal), molecular barcoding showed that seagrape mostly or exclusively associates with Scleroderma species (Basidiomycota) that were hitherto only known from Caribbean seagrape stands. An unknown Scleroderma species dominates in Brazil, Japan and Malaysia, while Scleroderma bermudense exclusively occurs in Réunion and Senegal. Population genetics analysis of S. bermudense did not detect any demographic bottleneck associated with a possible founder effect, but fungal populations from regions where seagrape is introduced are little differentiated from the Caribbean ones, separated by thousands of kilometers, consistently with relatively recent introduction. Moreover, dry seagrape fruits carry Scleroderma spores, probably because, when drying on beach sand, they aggregate spores from the spore bank accumulated by semi-hypogeous Scleroderma sporocarps. Aggregated spores inoculate seedlings, and their abundance may limit the founder effect after seagrape introduction. This rare pseudo-vertical transmission of mycorrhizal fungi likely contributed to efficient and repeated seagrape/Scleroderma co-introductions.
    Matched MeSH terms: Basidiomycota/isolation & purification; Spores, Fungal/isolation & purification; Mycorrhizae/isolation & purification
  2. A new cold-adapted, organic solvent stable lipase from mesophilic Staphylococcus epidermidis AT2
    Kamarudin NH, Rahman RN, Ali MS, Leow TC, Basri M, Salleh AB
    Protein J, 2014 Jun;33(3):296-307.
    PMID: 24777627 DOI: 10.1007/s10930-014-9560-3
    The gene encoding a cold-adapted, organic solvent stable lipase from a local soil-isolate, mesophilic Staphylococcus epidermidis AT2 was expressed in a prokaryotic system. A two-step purification of AT2 lipase was achieved using butyl sepharose and DEAE sepharose column chromatography. The final recovery and purification fold were 47.09 % and 3.45, respectively. The molecular mass of the purified lipase was estimated to be 43 kDa. AT2 lipase was found to be optimally active at pH 8 and stable at pH 6-9. Interestingly, this enzyme demonstrated remarkable stability at cold temperature (<30 °C) and exhibited optimal activity at a temperature of 25 °C. A significant enhancement of the lipolytic activity was observed in the presence of Ca(2+), Tween 60 and Tween 80. Phenylmethylsulfonylfluoride, a well known serine inhibitor did not cause complete inhibition of the enzymatic activity. AT2 lipase exhibited excellent preferences towards long chain triglycerides and natural oils. The lipolytic activity was stimulated by dimethylsulfoxide and diethyl ether, while more than 50 % of its activity was retained in methanol, ethanol, acetone, toluene, and n-hexane. Taken together, AT2 lipase revealed highly attractive biochemical properties especially because of its stability at low temperature and in organic solvents.
    Matched MeSH terms: Bacterial Proteins/isolation & purification; Lipase/isolation & purification; Recombinant Proteins/isolation & purification
  3. Antibacterial and antioxidant activity of naphthofuranquinones from the twigs of tropical mangrove Avicennia officinalis
    Assaw S, Mohd Amir MIH, Khaw TT, Bakar K, Mohd Radzi SA, Mazlan NW
    Nat Prod Res, 2020 Aug;34(16):2403-2406.
    PMID: 30600710 DOI: 10.1080/14786419.2018.1538220
    Mangrove plants are endowed with various biologically active compounds which have potent antibacterial and antioxidant properties. In present study, a bioactivity-guided fractionation for antibacterial and antioxidant active metabolites from the twigs of Avicennia officinalis collected from Kuala Selangor Nature Park, Selangor, Malaysia gave 13 major fractions. The antibacterial activity of A. officinalis fractions using well-diffusion showed strong selectivity on the Gram-positive bacteria (Staphylococcus epidermidis, S. aureus and Bacillus subtilis) with minimum inhibition concentration (MIC) values of 0.156-5.00 mg/mL. However, no antibacterial activities were observed on the Gram-negative bacteria (Vibrio cholera, Enterobacter cloacae and Escherichia coli). The active antibacterial fractions were further isolated using several chromatographic techniques to give two naphthofuranquinones, namely, avicenol C (1) and stenocarpoquinone B (2). Meanwhile, the antioxidant activity of A. officinalis fractions were evaluated using DPPH radical scavenging assay exhibited low antioxidant activities. Molecular structure of the naphthofuranquinones was elucidated using 1 D and 2 D NMR spectroscopy.
    Matched MeSH terms: Anti-Bacterial Agents/isolation & purification*; Antioxidants/isolation & purification*; Quinones/isolation & purification*
  4. Mechanistic investigation of phytochemicals involved in green synthesis of gold nanoparticles using aqueous Elaeis guineensis leaves extract: Role of phenolic compounds and flavonoids
    Ahmad T, Bustam MA, Irfan M, Moniruzzaman M, Asghar HMA, Bhattacharjee S
    Biotechnol Appl Biochem, 2019 Jul;66(4):698-708.
    PMID: 31172593 DOI: 10.1002/bab.1787
    Phytosynthesis of gold nanoparticles (AuNPs) has achieved an indispensable significance due to the diverse roles played by biomolecules in directing the physiochemical characteristics of biosynthesized nanoparticles. Therefore, the precise identification of key bioactive compounds involved in producing AuNPs is vital to control their tunable characteristics for potential applications. Herein, qualitative and quantitative determination of key biocompounds contributing to the formation of AuNPs using aqueous Elaeis guineensis leaves extract is reported. Moreover, roles of phenolic compounds and flavonoids in reduction of Au3+ and stabilization of AuNPs have been elucidated by establishing a reaction mechanism. Fourier-transform infrared spectroscopy (FTIR) showed shifting of O─H stretching vibrations toward longer wavenumbers and C═O toward shorter wavenumbers due to involvement of polyphenolic compounds in biosynthesis and oxidation of polyphenolic into carboxylic compounds, respectively, which cape nanoparticles to inhibit the aggregation. Congruently, pyrolysis-gas chromatography-mass spectrometry revealed the major contribution of polyphenolic compounds in the synthesis of AuNPs, which was further endorsed by reduction of total phenolic and total flavonoids contents from 48.08 ± 1.98 to 9.59 ± 0.92 mg GAE/g and 32.02 ± 1.31 to 13.8 ± 0.97 mg CE/g within 60 Min, respectively. Based on experimental results, reaction mechanism explained the roles of phenolic compounds and flavonoids in producing spherical-shaped AuNPs.
    Matched MeSH terms: Flavonoids/isolation & purification; Phenols/isolation & purification; Plant Extracts/isolation & purification
  5. Antifungal garcinia acid esters from the fruits of Garcinia atroviridis
    Mackeen MM, Ali AM, Lajis NH, Kawazu K, Kikuzaki H, Nakatani N
    Z Naturforsch C J Biosci, 2002 6 18;57(3-4):291-5.
    PMID: 12064729
    Two new garcinia acid derivatives, 2-(butoxycarbonylmethyl)-3-butoxycarbonyl-2-hydroxy-3-propanolide and 1',1"-dibutyl methyl hydroxycitrate, were isolated from the fruits of Garcinia atroviridis guided by TLC bioautography against the fungus Cladosporium herbarum. The structures of these compounds were established by spectral analysis. The former compound represents a unique beta-lactone structure and the latter compound is most likely an artefact of garcinia acid (= hydroxycitric acid). Both compounds showed selective antifungal activity comparable to that of cycloheximide (MID: 0.5 microg/spot) only against C herbarum at the MIDs of 0.4 and 0.8 microg/spot but were inactive against bacteria (Bacillus subtilis, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli), other fungi (Alternaria sp., Fusarium moniliforme and Aspergillus ochraceous) including the yeast Candida albicans.
    Matched MeSH terms: Antifungal Agents/isolation & purification; Citrates/isolation & purification; Lactones/isolation & purification
  6. Potential anti-epileptic phytoconstituents: An updated review
    Kaur J, Famta P, Famta M, Mehta M, Satija S, Sharma N, et al.
    J Ethnopharmacol, 2021 Mar 25;268:113565.
    PMID: 33166627 DOI: 10.1016/j.jep.2020.113565
    ETHNOPHARMACOLOGICAL RELEVANCE: Epilepsy is one of the most commonly occurring non-communicable neurological disorder that affects people of all age groups. Around 50 million people globally are epileptic, with 80% cases in developing countries due to lack of access to treatments determined by high cost and poor availability or it can be defined by the fraction of active epileptic patients who are not appropriately being treated. The availability of antiepileptic drugs and their adjuvant therapy in such countries is less than 50% and these are highly susceptible to drug interactions and severe adverse effects. As a result, the use of herbal medicine is increasingly becoming popular.

    AIM OF THE STUDY: To provide pharmacological information on the active constituents evaluated in the preclinical study to treat epilepsy with potential to be used as an alternative therapeutic option in future. It also provides affirmation for the development of novel antiepileptic drugs derived from medicinal plants.

    MATERIALS AND METHODS: Relevant information on the antiepileptic potential of phytoconstituents in the preclinical study (in-vitro, in-vivo) is provided based on their effect on screening parameters. Besides, relevant information on pharmacology of phytoconstituents, the traditional use of their medicinal plants related to epilepsy and status of phytoconstituents in the clinical study were derived from online databases, including PubMed, Clinicaltrial. gov, The Plant List (TPL, www.theplantlist.org), Science Direct. Articles identified using preset searching syntax and inclusion criteria are presented.

    RESULTS: More than 70% of the phytoconstituents reviewed in this paper justified the traditional use of their medicinal plant related to epilepsy by primarily acting on the GABAergic system. Amongst the phytoconstituents, only cannabidiol and tetrahydrocannabinol have been explored for clinical application in epilepsy.

    CONCLUSION: The preclinical and clinical data of the phytoconstituents to treat epilepsy and its associated comorbidities provides evidence for the discovery and development of novel antiepileptic drugs from medicinal plants. In terms of efficacy and safety, further randomized and controlled clinical studies are required to understand the complete pharmacodynamic and pharmacokinetic picture of phytoconstituents. Also, specific botanical source evaluation is needed.

    Matched MeSH terms: Anticonvulsants/isolation & purification; Plant Extracts/isolation & purification; Phytochemicals/isolation & purification
  7. Rainforest Conversion to Rubber Plantation May Not Result in Lower Soil Diversity of Bacteria, Fungi, and Nematodes
    Kerfahi D, Tripathi BM, Dong K, Go R, Adams JM
    Microb Ecol, 2016 08;72(2):359-71.
    PMID: 27221090 DOI: 10.1007/s00248-016-0790-0
    Large areas of rainforest in Asia have been converted to plantations, with uncertain effects on soil biodiversity. Using standard metagenetic methods, we compared the soil biota of bacteria, fungi, and nematodes at three rainforest sites in Malaysia with two rubber plantation sites with similar soils and geology. We predicted the following: (1) that the rubber sites would have a lower α- and β-diversity than the rainforest sites, due to the monospecific canopy cover and intensive management with herbicides, pesticides, and fertilizers, and (2) that due to differences in the physical and biotic environment associated with cultivation, there would be distinct communities of bacteria, fungi, and nematodes. However, regarding (1), the results showed no consistent difference in α- and β-diversity of bacteria, fungi, or nematodes between rainforest and rubber plantation sites. It appears that conversion of rainforest to rubber plantations does not necessarily result in a decrease in diversity of soil biota. It may be that heterogeneity associated with the cultivation regimen compensates for loss of biotically imposed heterogeneity of the original rainforest. Regarding (2), as predicted there were statistically significant differences in community composition between rainforest and rubber plantation for bacteria, fungi, and nematodes. These differences could be related to a range of factors including light level, litter fall composition, pH, C and N, selecting a distinct set of soil taxa, and it is possible that this in itself would affect long-term soil function.
    Matched MeSH terms: Bacteria/isolation & purification; Fungi/isolation & purification; Nematoda/isolation & purification*
  8. Molecularly imprinted silica gel incorporated with agarose polymer matrix as mixed matrix membrane for separation and preconcentration of sulfonamide antibiotics in water samples
    Rozaini MNH, Semail NF, Saad B, Kamaruzaman S, Abdullah WN, Rahim NA, et al.
    Talanta, 2019 Jul 01;199:522-531.
    PMID: 30952293 DOI: 10.1016/j.talanta.2019.02.096
    Molecularly imprinted silica gel (MISG) was incorporated through dispersion in agarose polymer matrix to form a mixed matrix membrane (MMM) and was applied for the determination of three sulfonamide antibiotic compounds (i.e. sulfamethoxazole (SMX), sulfamonomethoxine (SMM), and sulfadiazine (SDZ)) from environmental water samples. Several important microextraction conditions, such as type of desorption solvent, extraction time, amount of sorbent, sample volume, pH, and effect of desorption time, were comprehensively optimized. A preconcentration factors of ≥ 20 was achieved by the extraction of 12.5 mL of water samples using the developed method. This microextraction-HPLC method demonstrated good linearity (1-500 μg L-1) with a coefficient of determination (R2) of 0.9959-0.9999, low limits of detection (0.06-0.17 μg L-1) and limits of quantification (0.20-0.56 μg L-1), good analyte recoveries (80-96%), and acceptable relative standard deviations (< 10%) under the optimized conditions. The method is systematically compared to those reported in the literature.
    Matched MeSH terms: Anti-Bacterial Agents/isolation & purification*; Sulfonamides/isolation & purification*; Water Pollutants, Chemical/isolation & purification*
  9. Fulltext Preliminary Large Scale Mitigation of 3-Monochloropropane-1, 2-diol (3-MCPD) Esters and Glycidyl Esters in Palm Oil
    Ramli MR, Tarmizi AHA, Hammid ANA, Razak RAA, Kuntom A, Lin SW, et al.
    J Oleo Sci, 2020 Aug 06;69(8):815-824.
    PMID: 32641608 DOI: 10.5650/jos.ess20021
    Approximately 900 tonne of crude palm oil (CPO) underwent washing using 5 to 10% hot water (90 to 95°C) at a palm oil mill. The aim of the CPO washing was to eliminate and/or reduce total chlorine content present in the conventional CPO, as it is known as the main precursor for the formation of 3-monochloropropane-1, 2-diol esters (3-MCPDE). By a simple hot water washing, more than 85% of the total chlorine was removed. However, washing did not have significant (p > 0.05) effect on other oil quality parameters such as the deterioration of bleachability index (DOBI), free fatty acid (FFA) content and diacylglycerol (DAG) content of the oil. The latter has been established as the main precursor for glycidyl esters (GE) formation. The treated CPO was then transported using tankers and further refined at a commercial refinery. Refining of washed CPO resulted in significantly (p < 0.05) lower formation of 3-MCPDE, but GE content remained slightly high. Post-treatment of refined oil significantly reduced the GE content (p < 0.05) to an acceptable level whilst almost maintaining the low 3-MCPDE level. The study has proven that water washing of CPO prior to refining and subsequent post-refining is so far the most effective way to produce good quality refined oil with considerably low 3-MCPDE and GE contents. Dry fractionation of refined palm oil showed these contaminants partitioned more into the liquid olein fraction compared to the stearin fraction.
    Matched MeSH terms: alpha-Chlorohydrin/isolation & purification*; Chlorine/isolation & purification*; Esters/isolation & purification*
  10. Fulltext Performance and microbial diversity of palm oil mill effluent microbial fuel cell
    Jong BC, Liew PW, Lebai Juri M, Kim BH, Mohd Dzomir AZ, Leo KW, et al.
    Lett Appl Microbiol, 2011 Dec;53(6):660-7.
    PMID: 21967346 DOI: 10.1111/j.1472-765X.2011.03159.x
    To evaluate the bioenergy generation and the microbial community structure from palm oil mill effluent using microbial fuel cell.
    Matched MeSH terms: Betaproteobacteria/isolation & purification*; Gammaproteobacteria/isolation & purification; Deltaproteobacteria/isolation & purification*
  11. Pseuduvarines A and B, two new cytotoxic dioxoaporphine alkaloids from Pseuduvaria rugosa
    Taha H, Hadi AH, Nordin N, Najmuldeen IA, Mohamad K, Shirota O, et al.
    Chem Pharm Bull (Tokyo), 2011;59(7):896-7.
    PMID: 21720044
    Pseuduvarines A (1) and B (2), two new dioxoaporphine alkaloids with an amino moiety, were isolated from the stem bark of Pseuduvaria rugosa and their structures were elucidated by combination of 2D-NMR spectroscopic analysis. Pseuduvarines A (1) and B (2) showed cytotoxicity against MCF7, HepG2, and HL-60 (1: IC₅₀, 0.9, 21.7, and >50.0 µM, respectively, 2: IC₅₀ >50.0, 15.7, and 12.4 µM, respectively).
    Matched MeSH terms: Alkaloids/isolation & purification; Antineoplastic Agents, Phytogenic/isolation & purification; Aporphines/isolation & purification
  12. Monoamine oxidase inhibitory naphthoquinone and/or naphthalene dimers from Lemuni Hitam (Diospyros sp.), a Malaysian herbal medicine
    Okuyama E, Homma M, Satoh Y, Fujimoto H, Ishibashi M, Yamazaki M, et al.
    Chem Pharm Bull (Tokyo), 1999 Oct;47(10):1473-6.
    PMID: 10553643
    From the extract of a Malaysian herbal medicine, Lemuni Hitam (Diospyros sp.), which exhibited monoamine oxidase (MAO) inhibition, three new naphthoquinone and/or naphthalene dimers (lemuninols A-C, 1-3) were isolated together with 4,6-dihydroxy-5-methoxy-2-methyl-naphthalene (8) and six known monomers (4-7, 9 and 10). The structures were determined by spectroscopic methods including 2D-NMR techniques. Among them, lemuninol A showed 45% inhibition of MAO (mouse liver) at 5.0 x 10(-6) g/ml, and lemuninols B and C and a naphthoquinone (9) indicated weak activity. Some related quinones were also tested for their MAO inhibitory activities.
    Matched MeSH terms: Monoamine Oxidase Inhibitors/isolation & purification*; Naphthalenes/isolation & purification*; Naphthoquinones/isolation & purification*
  13. Fulltext Effect of Hybrid mono/bimetallic Nanocomposites for an enhancement of Catalytic and Antimicrobial Activities
    Sivaranjan K, Padmaraj O, Santhanalakshmi J, Sathuvan M, Sathiyaseelan A, Sagadevan S
    Sci Rep, 2020 02 13;10(1):2586.
    PMID: 32054936 DOI: 10.1038/s41598-020-59491-5
    Exploring the new catalytic systems for the reduction of organic and inorganic pollutants from an indispensable process in chemical, petrochemical, pharmaceutical and food industries, etc. Hence, in the present work, authors motivated to synthesize bare reduced graphene oxide (rGO), polyaniline (PANI), three different ratios of rGO-PANI(80:20,50:50, 10:90) composites and rGO-PANI(80:20,50:50, 10:90) supported mono (Pd) & bimetallic [Pd: Au(1:1,1:2, 2:1)] nanocomposite by a facile chemical reduction method. Also, it investigated their catalytic performances for the reduction of organic/inorganic pollutants and antimicrobial activities. All the freshly prepared bare rGO, PANI, three different ratios of rGO-PANI(80:20, 50:50,10:90) composites and rGO-PANI(80:20, 50:50,10:90)/Pd & Pd: Au(1:1, 1:2,2:1) nanocomposite hybrid catalysts were characterized using UV-Vis, FT-IR, SEM, FE-SEM, EDAX, HR-TEM, XRD, XPS and Raman spectroscopy analysis. Among them, an optimized best composition of rGO-PANI(80:20)/Pd: Au(1:1) bimetallic nanocomposite hybrid catalyst exhibits better catalytic reduction and antimicrobial activities than other composites, as a result of strong electrostatic interactions between rGO, PANI and bimetal (Pd: Au) NPs through a synergistic effect. Hence, an optimized rGO-PANI(80:20)/Pd:Au(1:1) bimetallic nanocomposite catalyst would be considered as a suitable catalyst for the reduction of different nitroarenes, organic dyes, heavy metal ions and also significantly inhibit the growth of S. aureus, S. Typhi as well as Candida albicans and Candida kruesi in wastewater.
    Matched MeSH terms: Coloring Agents/isolation & purification; Environmental Pollutants/isolation & purification; Nitro Compounds/isolation & purification
  14. Sulfated membrane adsorbers for economic pseudo-affinity capture of influenza virus particles
    Opitz L, Lehmann S, Reichl U, Wolff MW
    Biotechnol Bioeng, 2009 Aug 15;103(6):1144-54.
    PMID: 19449393 DOI: 10.1002/bit.22345
    Strategies to control outbreaks of influenza, a contagious respiratory tract disease, are focused mainly on prophylactic vaccinations in conjunction with antiviral medications. Currently, several mammalian cell culture-based influenza vaccine production processes are being established, such as the technologies introduced by Novartis Behring (Optaflu) or Baxter International Inc. (Celvapan). Downstream processing of influenza virus vaccines from cell culture supernatant can be performed by adsorbing virions onto sulfated column chromatography beads, such as Cellufine sulfate. This study focused on the development of a sulfated cellulose membrane (SCM) chromatography unit operation to capture cell culture-derived influenza viruses. The advantages of the novel method were demonstrated for the Madin Darby canine kidney (MDCK) cell-derived influenza virus A/Puerto Rico/8/34 (H1N1). Furthermore, the SCM-adsorbers were compared directly to column-based Cellufine sulfate and commercially available cation-exchange membrane adsorbers. Sulfated cellulose membrane adsorbers showed high viral product recoveries. In addition, the SCM-capture step resulted in a higher reduction of dsDNA compared to the tested cation-exchange membrane adsorbers. The productivity of the SCM-based unit operation could be significantly improved by a 30-fold increase in volumetric flow rate during adsorption compared to the bead-based capture method. The higher flow rate even further reduced the level of contaminating dsDNA by about twofold. The reproducibility and general applicability of the developed unit operation were demonstrated for two further MDCK cell-derived influenza virus strains: A/Wisconsin/67/2005 (H3N2) and B/Malaysia/2506/2004. Overall, SCM-adsorbers represent a powerful and economically favorable alternative for influenza virus capture over conventional methods using Cellufine sulfate.
    Matched MeSH terms: Influenza Vaccines/isolation & purification*; Influenza A Virus, H1N1 Subtype/isolation & purification*; Influenza A Virus, H3N2 Subtype/isolation & purification*
  15. Spectaflavoside A, a new potent iron chelating dimeric flavonol glycoside from the rhizomes of Zingiber spectabile Griff
    Sivasothy Y, Hadi AH, Mohamad K, Leong KH, Ibrahim H, Sulaiman SF, et al.
    Bioorg Med Chem Lett, 2012 Jun 1;22(11):3831-6.
    PMID: 22546674 DOI: 10.1016/j.bmcl.2012.02.064
    The rhizomes of Zingiber spectabile yielded a new dimeric flavonol glycoside for which the name kaempferol-3-O-(4″-O-acetyl)-α-L-rhamnopyranoside-(I-6,II-8)-kaempferol-3-O-(4″-O-acetyl)-α-L-rhamnopyranoside; spectaflavoside A (1) was proposed, along with kaempferol and its four acetylrhamnosides (2-6), demethoxycurcumin (7) and curcumin (8). The structure of spectaflavoside A was elucidated by spectroscopic methods including, 1D and 2D NMR techniques. This is the first report on the occurrence of a dimeric flavonol glycoside in the Zingiberaceae and the second in nature. Spectaflavoside A was found to be a potent iron chelating agent.
    Matched MeSH terms: Glycosides/isolation & purification; Iron Chelating Agents/isolation & purification; Flavones/isolation & purification
  16. Chrotacumines G-J, chromone alkaloids from Dysoxylum acutangulum with osteoclast differentiation inhibitory activity
    Morita H, Nugroho AE, Nagakura Y, Hirasawa Y, Yoshida H, Kaneda T, et al.
    Bioorg Med Chem Lett, 2014 Jun 1;24(11):2437-9.
    PMID: 24767841 DOI: 10.1016/j.bmcl.2014.04.020
    Four new chromone alkaloids, chrotacumines G-J (1-4), have been isolated from the barks of Dysoxylum acutangulum. Their structures and absolute configurations were elucidated on the basis of NMR and CD data. Chrotacumines G and J (1 and 4) showed osteoclast differentiation inhibitory activity in a dose dependent manner.
    Matched MeSH terms: Alkaloids/isolation & purification; Chromones/isolation & purification; Piperidines/isolation & purification
  17. Fulltext Mangrove derived Streptomyces sp. MUM265 as a potential source of antioxidant and anticolon-cancer agents
    Tan LT, Chan KG, Pusparajah P, Yin WF, Khan TM, Lee LH, et al.
    BMC Microbiol, 2019 02 13;19(1):38.
    PMID: 30760201 DOI: 10.1186/s12866-019-1409-7
    BACKGROUND: Colon cancer is the third most commonly diagnosed cancer worldwide, with a commensurately high mortality rate. The search for novel antioxidants and specific anticancer agents which may inhibit, delay or reverse the development of colon cancer is thus an area of great interest; Streptomyces bacteria have been demonstrated to be a source of such agents.

    RESULTS: The extract from Streptomyces sp. MUM265- a strain which was isolated and identified from Kuala Selangor mangrove forest, Selangor, Malaysia- was analyzed and found to exhibit antioxidant properties as demonstrated via metal-chelating ability as well as superoxide anion, DPPH and ABTS radical scavenging activities. This study also showed that MUM265 extract demonstrated cytotoxicity against colon cancer cells as evidenced by the reduced cell viability of Caco-2 cell line. Treatment with MUM265 extract induced depolarization of mitochondrial membrane potential and accumulation of subG1 cells in cell cycle analysis, suggesting that MUM265 exerted apoptosis-inducing effects on Caco-2 cells.

    CONCLUSION: These findings indicate that mangrove derived Streptomyces sp. MUM265 represents a valuable bioresource of bioactive compounds for the future development of chemopreventive agents, with particular promise suggested for treatment of colon cancer.

    Matched MeSH terms: Antineoplastic Agents/isolation & purification; Antioxidants/isolation & purification; Streptomyces/isolation & purification
  18. Molecular detection of pathogens from ectoparasites recovered from peri-domestic animals, and the first description of a Candidatus Midichloria sp. from Haemaphysalis wellingtoni from rural communities in Malaysia
    Khoo JJ, Husin NA, Lim FS, Oslan SNH, Mohd Azami SNI, To SW, et al.
    Parasitol Int, 2021 Feb;80:102202.
    PMID: 33038482 DOI: 10.1016/j.parint.2020.102202
    Rural communities in Malaysia have been shown to be exposed to Coxiella, Borrelia and rickettsial infections in previous seroprevalence studies. Further research is necessary to identify the actual causative agents and the potential vectors of these infections. The arthropods parasitizing peri-domestic animals in these communities may serve as the vector in transmitting arthropod-borne and zoonotic agents to the humans. Molecular screening of bacterial and zoonotic pathogens from ticks and fleas collected from dogs, cats and chickens from six rural communities in Malaysia was undertaken. These communities were made up of mainly the indigenous people of Malaysia, known as the Orang Asli, as well as settlers in oil palm plantations. The presence of Coxiella burnetii, Borrelia, and rickettsial agents, including Rickettsia and Anaplasma, was investigated by performing polymerase chain reaction (PCR) and DNA sequencing. Candidatus Rickettsia senegalensis was detected in one out of eight pools of Ctenocephalides felis fleas. A relapsing fever group Borrelia sp. was identified from one of seven Haemaphysalis hystricis ticks tested. The results from the PCR screening for Anaplasma unexpectedly revealed the presence of Candidatus Midichloria sp., a potential tick endosymbiont, in two out of fourteen Haemaphysalis wellingtoni ticks tested. C. burnetii was not detected in any of the samples tested. The findings here provide evidence for the presence of potentially novel strains of rickettsial and borrelial agents in which their impact on public health risks among the rural communities in Malaysia merit further investigation. The detection of a potential endosymbiont of ticks also suggest that the presence of tick endosymbionts in the region is not fully explored.
    Matched MeSH terms: Anaplasma/isolation & purification; Borrelia/isolation & purification; Coxiella burnetii/isolation & purification
  19. Investigating the decay rates of Escherichia coli relative to Vibrio parahemolyticus and Salmonella Typhi in tropical coastal waters
    Lee CW, Ng AY, Bong CW, Narayanan K, Sim EU, Ng CC
    Water Res, 2011 Feb;45(4):1561-70.
    PMID: 21146847 DOI: 10.1016/j.watres.2010.11.025
    Using the size fractionation method, we measured the decay rates of Escherichia coli, Salmonella Typhi and Vibrio parahaemolyticus in the coastal waters of Peninsular Malaysia. The size fractions were total or unfiltered, <250 μm, <20 μm, <2 μm, <0.7 μm, <0.2 μm and <0.02 μm. We also carried out abiotic (inorganic nutrients) and biotic (bacterial abundance, production and protistan bacterivory) measurements at Port Dickson, Klang and Kuantan. Klang had highest nutrient concentrations whereas both bacterial production and protistan bacterivory rates were highest at Kuantan. We observed signs of protist-bacteria coupling via the following correlations: Protistan bacterivory-Bacterial Production: r = 0.773, df = 11, p < 0.01; Protist-Bacteria: r = 0.586, df = 12, p < 0.05. However none of the bacterial decay rates were correlated with the biotic variables measured. E. coli and Salmonella decay rates were generally higher in the larger fraction (>0.7 μm) than in the smaller fraction (<0.7 μm) suggesting the more important role played by protists. E. coli and Salmonella also decreased in the <0.02 μm fraction and suggested that these non-halophilic bacteria did not survive well in seawater. In contrast, Vibrio grew well in seawater. There was usually an increase in Vibrio after one day incubation. Our results confirmed that decay or loss rates of E. coli did not match that of Vibrio, and also did not correlate with Salmonella decay rates. However E. coli showed persistence where its decay rates were generally lower than Salmonella.
    Matched MeSH terms: Escherichia coli/isolation & purification*; Salmonella typhi/isolation & purification*; Vibrio parahaemolyticus/isolation & purification*
  20. Comparative Neuroprotective, Anti-Inflammatory and Neurite Outgrowth Activities of Extracts of King Oyster Mushroom, Pleurotus eryngii (Agaricomycetes)
    Kushairi N, Phan CW, Sabaratnam V, Vidyadaran S, Naidu M, David P
    Int J Med Mushrooms, 2020;22(12):1171-1181.
    PMID: 33463934 DOI: 10.1615/IntJMedMushrooms.2020036938
    Pleurotus eryngii (king oyster mushroom) is a renowned culinary mushroom with various medicinal properties that may be beneficial for health maintenance and disease prevention. However, its effect on the nervous system remains elusive. In this study, hot water (PE-HWA) and ethanol (PE-ETH) extracts of P. eryngii were investigated and compared for their neuroprotective, anti-inflammatory, and neurite outgrowth activities in vitro. Based on the results, both extracts up to 400 μg/mL were nontoxic to PC12 cells and BV2 microglia (p > 0.05). Treatment with 250 μM hydrogen peroxide (H2O2) markedly (p < 0.0001) reduced the PC12 cell viability to 67.74 ± 6.47%. Coincubation with 200 μg/mL and 400 μg/mL of PE-ETH dose-dependently increased the cell viability to 85.34 ± 1.91% (p < 0.001) and 98.37 ± 6.42% (p < 0.0001) respectively, while PE-HWA showed no activity. Nitric oxide (NO) released by BV2 microglia was notably (p < 0.0001) increased by 1 μg/mL lipopolysaccharides (LPS) from 7.46 ± 0.73 μM to 80.00 ± 3.78 μM indicating an inflammatory reaction. However, coincubation with 200 and 400 μg/mL of PE-ETH significantly (p < 0.0001) reduced the NO level to 58.57 ± 6.19 μM and 52.86 ± 3.43 μM respectively, while PE-HWA was noneffective. PE-ETH and PE-HWA at 40 μg/mL significantly increased the neurite-bearing cells from 4.70 ± 3.36% to 13.12 ± 2.82% (p < 0.01) and 20.93 ± 5.37% (p < 0.0001) respectively. Pleurotus eryngii, particularly the ethanol extract (PE-ETH) and its potentially bioactive compounds, could be explored as a neurohealth promoting agent, due to its collective neuroprotective, anti-inflammatory, and neurite outgrowth activities.
    Matched MeSH terms: Anti-Inflammatory Agents/isolation & purification; Plant Extracts/isolation & purification; Neuroprotective Agents/isolation & purification
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