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  1. Fulltext Genome-Wide Discovery of Genes Required for Capsule Production by Uropathogenic Escherichia coli
    Goh KGK, Phan MD, Forde BM, Chong TM, Yin WF, Chan KG, et al.
    mBio, 2017 10 24;8(5).
    PMID: 29066548 DOI: 10.1128/mBio.01558-17
    Uropathogenic Escherichia coli (UPEC) is a major cause of urinary tract and bloodstream infections and possesses an array of virulence factors for colonization, survival, and persistence. One such factor is the polysaccharide K capsule. Among the different K capsule types, the K1 serotype is strongly associated with UPEC infection. In this study, we completely sequenced the K1 UPEC urosepsis strain PA45B and employed a novel combination of a lytic K1 capsule-specific phage, saturated Tn5 transposon mutagenesis, and high-throughput transposon-directed insertion site sequencing (TraDIS) to identify the complement of genes required for capsule production. Our analysis identified known genes involved in capsule biosynthesis, as well as two additional regulatory genes (mprA and lrhA) that we characterized at the molecular level. Mutation of mprA resulted in protection against K1 phage-mediated killing, a phenotype restored by complementation. We also identified a significantly increased unidirectional Tn5 insertion frequency upstream of the lrhA gene and showed that strong expression of LrhA induced by a constitutive Pcl promoter led to loss of capsule production. Further analysis revealed loss of MprA or overexpression of LrhA affected the transcription of capsule biosynthesis genes in PA45B and increased sensitivity to killing in whole blood. Similar phenotypes were also observed in UPEC strains UTI89 (K1) and CFT073 (K2), demonstrating that the effects were neither strain nor capsule type specific. Overall, this study defined the genome of a UPEC urosepsis isolate and identified and characterized two new regulatory factors that affect UPEC capsule production.IMPORTANCE Urinary tract infections (UTIs) are among the most common bacterial infections in humans and are primarily caused by uropathogenic Escherichia coli (UPEC). Many UPEC strains express a polysaccharide K capsule that provides protection against host innate immune factors and contributes to survival and persistence during infection. The K1 serotype is one example of a polysaccharide capsule type and is strongly associated with UPEC strains that cause UTIs, bloodstream infections, and meningitis. The number of UTIs caused by antibiotic-resistant UPEC is steadily increasing, highlighting the need to better understand factors (e.g., the capsule) that contribute to UPEC pathogenesis. This study describes the original and novel application of lytic capsule-specific phage killing, saturated Tn5 transposon mutagenesis, and high-throughput transposon-directed insertion site sequencing to define the entire complement of genes required for capsule production in UPEC. Our comprehensive approach uncovered new genes involved in the regulation of this key virulence determinant.
    Matched MeSH terms: Polysaccharides, Bacterial/biosynthesis*
  2. [Exploring molecular mechanisms of fucoidan in improving human proximal renal tubular epithelial cells aging by targeting autophagy signaling pathways]
    Fang QJ, Liu JJ, Wan YG, Liu BH, Tu Y, Wu W, et al.
    Zhongguo Zhong Yao Za Zhi, 2020 Dec;45(24):6003-6011.
    PMID: 33496141 DOI: 10.19540/j.cnki.cjcmm.20200709.401
    Fucoidan(FPS) is an effective component of the Chinese patent medicine named Haikun Shenxi, which treats schronic renal failure in clinics, and has the potential anti-aging effects. However, it is still unclear whether FPS can improve renal aging, especially the molecular mechanism of its anti-aging. The human proximal renal tubular epithelial cells(HK-2) in vitro were divided into normal group(N), D-gal model group(D), low dose of FPS group(L-FPS), high dose of FPS group(H-FPS) and vitamin E group(VE), and treated by the different measures, respectively. More specifically, the HK-2 cells in each group were separately treated by 1 mL of 1% fetal bovine serum(FBS) or D-galactose(D-gal, 75 mmol·L~(-1)) or D-gal(75 mmol·L~(-1))+FPS(25 μg·mL~(-1)) or D-gal(75 mmol·L~(-1))+FPS(50 μg·mL~(-1)) or D-gal(75 mmol·L~(-1))+VE(50 μg·mL~(-1)). After the treatment for 24 h, firstly, the effects of D-gal on senescence-associated β-galactosidase(SA-β-gal) staining characteristics and klotho, P53 and P21 protein expression le-vels, as well as adenosine monophosphate activated protein kinase(AMPK)-uncoordinated 51-like kinase 1(ULK1) signaling pathway activation in the HK-2 cells were detected, respectively. Secondly, the effects of FPS and VE on SA-β-gal staining characteristics and klotho, P53 and P21 protein expression levels in the HK-2 cells exposed to D-gal were investigated, respectively. Finally, the effects of FPS and VE on microtubule-associated protein 1 light chain 3(LC3) protein expression level and AMPK-ULK1 signaling pathway activation in the HK-2 cells exposed to D-gal were examined severally. The results indicated that, for the HK-2 cells, the dose of 75 mmol·L~(-1) D-gal could induce the changes of SA-β-gal staining characteristics and klotho, P53 and P21 protein expression levels. That is causing cells aging. FPS and VE could both ameliorate the changes of SA-β-gal staining characteristics and klotho, P53 and P21 protein expression levels in the HK-2 cells exposed to D-gal. That is anti-cells aging, here, the functions of FPS and VE are similar. D-gal could not only induce cell aging but also increase LC3Ⅱ, phosphorylated-AMPK(p-AMPK) and phosphorylated-ULK1(p-ULK1) protein expressions, and activate autophagy-related AMPK-ULK1 signaling pathway. FPS and VE could both improve the changes of LC3Ⅱ, p-AMPK and p-ULK1 protein expression levels in the HK-2 cells exposed to D-gal. That is inhibiting autophagy-related AMPK-ULK1 signaling pathway activation. On the whole, for the human proximal renal tubular epithelial cells aging models induced by D-gal, FPS similar to VE, can ameliorate renal cells aging by possibly inhibiting autophagy-related AMPK-ULK1 signaling pathway activation. This finding provides the preliminary pharmacologic evidences for FPS protecting against renal aging.
    Matched MeSH terms: Polysaccharides
  3. Enhanced phenol degradation by immobilized Acinetobacter sp. strain AQ5NOL 1
    Ahmad SA, Shamaan NA, Arif NM, Koon GB, Shukor MY, Syed MA
    World J Microbiol Biotechnol, 2012 Jan;28(1):347-52.
    PMID: 22806810 DOI: 10.1007/s11274-011-0826-z
    A locally isolated Acinetobacter sp. Strain AQ5NOL 1 was encapsulated in gellan gum and its ability to degrade phenol was compared with the free cells. Optimal phenol degradation was achieved at gellan gum concentration of 0.75% (w/v), bead size of 3 mm diameter (estimated surface area of 28.26 mm(2)) and bead number of 300 per 100 ml medium. At phenol concentration of 100 mg l(-1), both free and immobilized bacteria exhibited similar rates of phenol degradation but at higher phenol concentrations, the immobilized bacteria exhibited a higher rate of degradation of phenol. The immobilized cells completely degrade phenol within 108, 216 and 240 h at 1,100, 1,500 and 1,900 mg l(-1) phenol, respectively, whereas free cells took 240 h to completely degrade phenol at 1,100 mg l(-1). However, the free cells were unable to completely degrade phenol at higher concentrations. Overall, the rates of phenol degradation by both immobilized and free bacteria decreased gradually as the phenol concentration was increased. The immobilized cells showed no loss in phenol degrading activity after being used repeatedly for 45 cycles of 18 h cycle. However, phenol degrading activity of the immobilized bacteria experienced 10 and 38% losses after the 46 and 47th cycles, respectively. The study has shown an increased efficiency of phenol degradation when the cells are encapsulated in gellan gum.
    Matched MeSH terms: Polysaccharides, Bacterial
  4. Pink oyster mushroom Pleurotus flabellatus mycelium produced by an airlift bioreactor-the evidence of potent in vitro biological activities
    Klaus A, Wan-Mohtar WAAQI, Nikolić B, Cvetković S, Vunduk J
    World J Microbiol Biotechnol, 2021 Jan 04;37(1):17.
    PMID: 33394203 DOI: 10.1007/s11274-020-02980-6
    Four types of mycelial extracts were derived from the airlift liquid fermentation (ALF) of Pleurotus flabellatus, namely exopolysaccharide (EX), endopolysaccharide (EN), hot water (WE), and hot alkali (AE) extracts. Such extracts were screened for their active components and biological potential. EN proved to be most effective in inhibition of lipid peroxidation (EC50 = 1.71 ± 0.02 mg/mL) and in Cupric ion reducing antioxidant capacity (CUPRAC) assay (EC50 = 2.91 ± 0.01 mg TE/g). AE exhibited most pronounced ability to chelate ferrous ions (EC50 = 4.96 ± 0.08 mg/mL) and to scavenge ABTS radicals (EC50 = 3.36 ± 0.03 mg TE/g). β-glucans and total phenols contributed most to the chelating ability and quenching of ABTS radicals. Inhibition of lipid peroxidation correlated best with total glucans, total proteins, and β-glucans. Total proteins contributed most to CUPRAC antioxidant capacity. Antifungal effect was determined against Candida albicans ATCC 10231 (MIC: 0.019-0.625 mg/mL; MFC: 0.039-2.5 mg/mL), and towards C. albicans clinical isolate (MIC and MFC: 10.0-20.0 mg/mL). Comparison of cytotoxicity against colorectal carcinoma HCT 116 cells (IC50: 1.8 ± 0.3-24.6 ± 4.2 mg/mL) and normal lung MRC-5 fibroblasts (IC50: 17.0 ± 4.2-42.1 ± 6.1 mg/mL) showed that EN, and especially AE possess selective anticancer activity (SI values 3.41 and 9.44, respectively). Slight genotoxicity was observed only for AE and EX, indicating the low risk concerning this feature. Notable antioxidative and anticandidal activities, selective cytotoxicity against colorectal carcinoma cells, and absence/low genotoxicity pointed out that ALF-cultivated P. flabellatus mycelium could be considered as a valuable source of bioactive substances.
    Matched MeSH terms: Fungal Polysaccharides/isolation & purification; Fungal Polysaccharides/pharmacology
  5. Effect of high temperature toward microalgal organic matter and its impact toward membrane distillation application
    Cheah YT, Lakbir Singh HKK, Chan DJC
    Water Environ Res, 2021 Jan 23.
    PMID: 33484623 DOI: 10.1002/wer.1515
    Membrane distillation (MD) frequently deals with membrane biofouling caused by deposition of algal organic matter (AOM) from algal blooms, hampering the treatment efficiency. In this study, AOMs, which are soluble extracellular polymeric substance (sEPS), bounded EPS (bEPS), and internal organic matter (IOM) from three benthic species (Amphora coffeaeformis, Cylindrotheca fusiformis, and Navicula incerta) were exposed to a temperature range to resemble the MD process. Results showed that EPS had higher polysaccharide fraction than protein with 85.71%, 68.26%, and 71.91% for A. coffeaeformis, N. incerta, and C. fusiformis, respectively. Both the EPS polysaccharide and protein concentration linearly increase with temperature, but the opposite was true for IOM and high-molecular-weight (HMW) polysaccharide. At 80°C, 5812.94 μg/g out of 6304.28 μg/g polysaccharide in A. coffeaeformis was of low molecular weight (LMW); hence, these findings suggested that they were the major foulants to clog the narrow pores within virgin hydrophobic membrane, forming a conditioning layer followed by deposition of HMW and hydrophilic polysaccharides onto the macropores to cause irreversible fouling. Cell lysis occurring at higher temperature increases the total protein content about 25% within the EPS matrix, inducing membrane plugging via hydrophobic-hydrophobic interactions. Overall, the AOM composition at different temperatures will likely dictate the fouling severity in MD. PRACTITIONER POINTS: EPS production of three benthic diatoms was the highest at 80°C. EPS from diatoms consists of at least 75.29% of polysaccharides. Small molecular weight carbohydrates (<12 kDa) were potential foulants. Proteins of internal organic matter (>56%) give irreversible attachment towards membranes. A. coffeaeformis was considered as the most fouling diatoms with highest EPS amount of 6304.28 μg/g.
    Matched MeSH terms: Polysaccharides
  6. Economic Impact of Pneumococcal Protein-D Conjugate Vaccine (PHiD-CV) on the Malaysian National Immunization Programme
    Aljunid S, Maimaiti N, Ahmed Z, Muhammad Nur A, Md Isa Z, Azmi S, et al.
    Value Health Reg Issues, 2014 May;3:146-155.
    PMID: 29702920 DOI: 10.1016/j.vhri.2014.04.008
    OBJECTIVE: To assess the cost-effectiveness of introducing pneumococcal polysaccharide and nontypeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) in the National Immunization Programme of Malaysia. This study compared introducing PHiD-CV (10 valent vaccine) with current no vaccination, as well as against the alternative 13-valent pneumococcal conjugate vaccine (PCV13).

    METHODS: A lifetime Markov cohort model was adapted using national estimates of disease burden, outcomes of pneumococcal disease, and treatment costs of disease manifestations including pneumonia, acute otitis media, septicemia, and meningitis for a hypothetical birth cohort of 550,000 infants. Clinical information was obtained by review of medical records from four public hospitals in Malaysia from the year 2008 to 2009. Inpatient cost from the four study hospitals was obtained from a diagnostic-related group-based costing system. Outpatient cost was estimated using clinical pathways developed by an expert panel. The perspective assessed was that of the Ministry of Health, Malaysia.

    RESULTS: The estimated disease incidence was 1.2, 3.7, 70, and 6.9 per 100,000 population for meningitis, bacteremia, pneumonia, and acute otitis media, respectively. The Markov model predicted medical costs of Malaysian ringgit (RM) 4.86 billion (US $1.51 billion) in the absence of vaccination. Vaccination with PHiD-CV would be highly cost-effective against no vaccination at RM30,290 (US $7,407) per quality-adjusted life-year gained. On comparing PHiD-CV with PCV13, it was found that PHiD-CV dominates PCV13, with 179 quality-adjusted life-years gained while saving RM35 million (US $10.87 million).

    CONCLUSIONS: It is cost-effective to incorporate pneumococcal vaccination in the National Immunization Programme of Malaysia. Our model suggests that PHiD-CV would be more cost saving than PCV13 from the perspective of the Ministry of Health of Malaysia.

    Study site: UKM Medical Centre, Hospital Kuala Lumpur, Hospital
    Alor Setar, and Hospital Queen Elizabeth, Kota Kinabalu
    Matched MeSH terms: Polysaccharides
  7. Typhoid fever--important issues still remain
    Pang T, Levine MM, Ivanoff B, Wain J, Finlay BB
    Trends Microbiol., 1998 Apr;6(4):131-3.
    PMID: 9587187
    Matched MeSH terms: Polysaccharides, Bacterial/immunology
  8. Mushroom immunomodulators: unique molecules with unlimited applications
    El Enshasy HA, Hatti-Kaul R
    Trends Biotechnol, 2013 Dec;31(12):668-77.
    PMID: 24125745 DOI: 10.1016/j.tibtech.2013.09.003
    For centuries, mushrooms have been used as food and medicine in different cultures. More recently, many bioactive compounds have been isolated from different types of mushrooms. Among these, immunomodulators have gained much interest based on the increasing growth of the immunotherapy sector. Mushroom immunomodulators are classified under four categories based on their chemical nature as: lectins, terpenoids, proteins, and polysaccharides. These compounds are produced naturally in mushrooms cultivated in greenhouses. For effective industrial production, cultivation is carried out in submerged culture to increase the bioactive compound yield, decrease the production time, and reduce the cost of downstream processing. This review provides a comprehensive overview on mushroom immunomodulators in terms of chemistry, industrial production, and applications in medical and nonmedical sectors.
    Matched MeSH terms: Polysaccharides
  9. Fulltext The use of D-optimal mixture design in optimising okara soap formulation for stratum corneum application
    Borhan FP, Abd Gani SS, Shamsuddin R
    ScientificWorldJournal, 2014;2014:173979.
    PMID: 25548777 DOI: 10.1155/2014/173979
    Okara, soybean waste from tofu and soymilk production, was utilised as a natural antioxidant in soap formulation for stratum corneum application. D-optimal mixture design was employed to investigate the influence of the main compositions of okara soap containing different fatty acid and oils (virgin coconut oil A (24-28% w/w), olive oil B (15-20% w/w), palm oil C (6-10% w/w), castor oil D (15-20% w/w), cocoa butter E (6-10% w/w), and okara F (2-7% w/w)) by saponification process on the response hardness of the soap. The experimental data were utilized to carry out analysis of variance (ANOVA) and to develop a polynomial regression model for okara soap hardness in terms of the six design factors considered in this study. Results revealed that the best mixture was the formulation that included 26.537% A, 19.999% B, 9.998% C, 16.241% D, 7.633% E, and 7.000% F. The results proved that the difference in the level of fatty acid and oils in the formulation significantly affects the hardness of soap. Depending on the desirable level of those six variables, creation of okara based soap with desirable properties better than those of commercial ones is possible.
    Matched MeSH terms: Polysaccharides/pharmacology*
  10. Fulltext Conversion of lignocellulosic biomass to nanocellulose: structure and chemical process
    Lee HV, Hamid SB, Zain SK
    ScientificWorldJournal, 2014;2014:631013.
    PMID: 25247208 DOI: 10.1155/2014/631013
    Lignocellulosic biomass is a complex biopolymer that is primary composed of cellulose, hemicellulose, and lignin. The presence of cellulose in biomass is able to depolymerise into nanodimension biomaterial, with exceptional mechanical properties for biocomposites, pharmaceutical carriers, and electronic substrate's application. However, the entangled biomass ultrastructure consists of inherent properties, such as strong lignin layers, low cellulose accessibility to chemicals, and high cellulose crystallinity, which inhibit the digestibility of the biomass for cellulose extraction. This situation offers both challenges and promises for the biomass biorefinery development to utilize the cellulose from lignocellulosic biomass. Thus, multistep biorefinery processes are necessary to ensure the deconstruction of noncellulosic content in lignocellulosic biomass, while maintaining cellulose product for further hydrolysis into nanocellulose material. In this review, we discuss the molecular structure basis for biomass recalcitrance, reengineering process of lignocellulosic biomass into nanocellulose via chemical, and novel catalytic approaches. Furthermore, review on catalyst design to overcome key barriers regarding the natural resistance of biomass will be presented herein.
    Matched MeSH terms: Polysaccharides/metabolism; Polysaccharides/chemistry
  11. Fulltext Intrastrain comparison of the chemical composition and antioxidant activity of an edible mushroom, Pleurotus giganteus, and its potent neuritogenic properties
    Phan CW, David P, Tan YS, Naidu M, Wong KH, Kuppusamy UR, et al.
    ScientificWorldJournal, 2014;2014:378651.
    PMID: 25121118 DOI: 10.1155/2014/378651
    Two strains of Pleurotus giganteus (commercial and wild) were tested for their ability to induce neurite outgrowth in rat pheochromocytoma (PC12) and mouse neuroblastoma-2a (N2a) cells. Treatment with the mushroom extracts resulted in neuronal differentiation and neuronal elongation, but not nerve growth factor (NGF) production. Linoleic acid (4.5-5.0%, w/w) which is a major fatty acid present in the ethanol extract promoted NGF biosynthesis when augmented with low concentration of NGF (5 ng/mL). The two strains of mushroom were found to be high in protein (154-192 g kg(-1)), total polysaccharides, phenolics, and flavonoids as well as vitamins B1, B2, and B3. The total phenolics present in the mushroom extracts were positively correlated to the antioxidant activity (free radical scavenging, ferric reducing power, and lipid peroxidation inhibition). To conclude, P. giganteus could potentially be used in well-balanced diet and as a source of dietary antioxidant to promote neuronal health.
    Matched MeSH terms: Polysaccharides/analysis
  12. Fulltext Biodegradation of palm kernel cake by cellulolytic and hemicellulolytic bacterial cultures through solid state fermentation
    Alshelmani MI, Loh TC, Foo HL, Lau WH, Sazili AQ
    ScientificWorldJournal, 2014;2014:729852.
    PMID: 25019097 DOI: 10.1155/2014/729852
    Four cellulolytic and hemicellulolytic bacterial cultures were purchased from the Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Culture (DSMZ) and the American Type Culture Collection (ATCC). Two experiments were conducted; the objective of the first experiment was to determine the optimum time period required for solid state fermentation (SSF) of palm kernel cake (PKC), whereas the objective of the second experiment was to investigate the effect of combinations of these cellulolytic and hemicellulolytic bacteria on the nutritive quality of the PKC. In the first experiment, the SSF was lasted for 12 days with inoculum size of 10% (v/w) on different PKC to moisture ratios. In the second experiment, fifteen combinations were created among the four microbes with one untreated PKC as a control. The SSF lasted for 9 days, and the samples were autoclaved, dried, and analyzed for proximate analysis. Results showed that bacterial cultures produced high enzymes activities at the 4th day of SSF, whereas their abilities to produce enzymes tended to be decreased to reach zero at the 8th day of SSF. Findings in the second experiment showed that hemicellulose and cellulose was significantly (P < 0.05) decreased, whereas the amount of reducing sugars were significantly (P < 0.05) increased in the fermented PKC (FPKC) compared with untreated PKC.
    Matched MeSH terms: Polysaccharides/metabolism*
  13. Fulltext Anticancer and antitumor potential of fucoidan and fucoxanthin, two main metabolites isolated from brown algae
    Zorofchian Moghadamtousi S, Karimian H, Khanabdali R, Razavi M, Firoozinia M, Zandi K, et al.
    ScientificWorldJournal, 2014;2014:768323.
    PMID: 24526922 DOI: 10.1155/2014/768323
    Seaweed is one of the largest producers of biomass in marine environment and is a rich arsenal of active metabolites and functional ingredients with valuable beneficial health effects. Being a staple part of Asian cuisine, investigations on the crude extracts of Phaeophyceae or brown algae revealed marked antitumor activity, eliciting a variety of research to determine the active ingredients involved in this potential. The sulfated polysaccharide of fucoidan and carotenoid of fucoxanthin were found to be the most important active metabolites of brown algae as potential chemotherapeutic or chemopreventive agents. This review strives to provide detailed account of all current knowledge on the anticancer and antitumor activity of fucoidan and fucoxanthin as the two major metabolites isolated from brown algae.
    Matched MeSH terms: Polysaccharides/isolation & purification; Polysaccharides/metabolism*; Polysaccharides/therapeutic use
  14. Evaluation on the decomposability of tropical forest peat soils after conversion to an oil palm plantation
    Sangok FE, Maie N, Melling L, Watanabe A
    Sci Total Environ, 2017 Jun 01;587-588:381-388.
    PMID: 28242223 DOI: 10.1016/j.scitotenv.2017.02.165
    To understand the variations in the decomposability of tropical peat soil following deforestation for an oil palm plantation, a field incubation experiment was conducted in Sarawak, Malaysia. Peat soils collected from three types of primary forest, namely Mixed Peat Swamp (MPS; Gonystylus-Dactylocladus-Neoscrotechinia association), Alan Batu (ABt; Shorea albida-Gonstylus-Strenonurus association), and Alan Bunga (ABg; Shorea albida association), were packed in polyvinyl chloride pipes and installed in an oil palm plantation. Carbon dioxide (CO2) and methane (CH4) fluxes from soil were monthly measured for 3years. Environmental variables including soil temperature, soil moisture content, and groundwater table were also monitored. The pH, loss on ignition, and total carbon (C) content were similar among the three soils, while total N content was larger in the MPS than in the ABg soils. Based on13C nuclear magnetic resonance (NMR) spectroscopy, C composition of the MPS and ABg soils was characterized by the largest proportion of C present as alkyl C and O-alkyl C, respectively. The C composition of the ABt soil was intermediate between the MPS and ABg soils. The CO2fluxes from the three soils ranged from 78 to 625mgCm-2h-1with a negative correlation to groundwater level. The CH4fluxes ranged from -67 to 653μgCm-2h-1. Both total CO2and CH4fluxes were larger in the order ABg>ABt>MPS (P<0.05). Annual rate of peat decomposition as was estimated from cumulative C loss differed up to 2 times, and the rate constant in exponential decay model was 0.033y-1for the MPS soil and 0.066y-1for the ABg soil. The field incubation results of the three forest peat soils seem to reflect the difference in the labile organic matter content, represented by polysaccharides.
    Matched MeSH terms: Polysaccharides
  15. Improvement of wheat straw anaerobic digestion through alkali pre-treatment: Carbohydrates bioavailability evaluation and economic feasibility
    Romero-Güiza MS, Wahid R, Hernández V, Møller H, Fernández B
    Sci Total Environ, 2017 Oct 01;595:651-659.
    PMID: 28402918 DOI: 10.1016/j.scitotenv.2017.04.006
    Lignocellulosic biomasses such as wheat straw are widely used as a feedstock for biogas production. However, these biomasses are mainly composed of a compact fibre structure and therefore, it is recommended to treat them prior to its usage for biogas production in order to improve their bioavailability. The aim of this work is to evaluate, in terms of performance stability, methane yield and economic feasibility, two different scenarios: a mesophilic codigestion of wheat straw and animal manure with or without a low-energy demand alkaline pre-treatment (0.08gKOHgTS-1of wheat straw, for 24h and at 25°C). Besides this, said pre-treatment was also analysed based on the improvement of the bioavailable carbohydrate content in the untreated versus the pre-treated wheat straw. The results pointed out that pre-treated wheat straw prompted a more stable performance (in terms of pH and alkalinity) and an improved methane yield (128% increment) of the mesophilic codigestion process, in comparison to the "untreated" scenario. The pre-treatment increased the content of cellulose, hemicellulose and other compounds (waxes, pectin, oil, etc.) in the liquid fraction, from 5% to 60%, from 11.5% to 39.1% TS and from 57% to 79% of the TS in the liquid fraction for the untreated and pre-treated wheat straws, respectively. Finally, the pre-treated scenario gained an energy surplus of a factor 13.5 and achieved a positive net benefit of 90.4€tVS-WS-1d-1, being a favourable case for an eventual scale-up of the combined process.
    Matched MeSH terms: Polysaccharides
  16. Fulltext Review article: appropriate hydrothermal pretreatment of oil palm biomass in palm oil mill
    Khairiatul Nabilah Jansar, Ahmad Muhaimin Roslan, Mohd Ali Hassan
    The Pertanika Journal of Scholarly Research Reviews, 2018;4(1):31-40.
    MyJurnal
    Oil palm (Elaeis guineensis Jacq.) is one of the most planted trees in Malaysia for the palm oil production. Thus, solid biomass had been generated from this industry such as empty fruit bunch, shell, mesocarp fibre, frond and trunk produced that causes problematic to the nation and expected to escalate up to 85-110 million tonnes by 2020. Besides that, palm oil mill effluent and excessive steam also generated from the production of palm oil. In situ hydrothermal pretreatment means the utilisation of excessive steam produced by the oil palm mill and at the same time, generating value added product as well as reducing the biomass. Oil palm biomass is rich in lignocellulosic materials which comprised of lignin, hemicellulose and cellulose. Refinement of lignocellulosic from oil palm biomass can be utilised to form fermentable sugar, bioethanol and other potential chemicals. Recalcitrant property of lignocellulosic reduces the ability of enzymes to penetrate, thus pretreatment is required prior to hydrolysis process. Pretreatment can be either physical, chemical, biological or combined. In this review paper, three types of hydrothermal pretreatment were discussed as suitable in situ pretreatment process for oil palm biomass; in palm oil mill. The suitability was measured based on the availability of excess steam and energy in the mill. Furthermore, physicochemical pretreatment also facilitate the saccharification process, whereby it loosened the lignocellulose structure and increase the surface area. The effects and factors in choosing right pretreatment are highlighted in this paper.
    Matched MeSH terms: Polysaccharides
  17. Fulltext Sulfated galactans from red seaweeds and their potential applications
    Lim, Yi-Yi, Lee, Wei-Kang, Leow, Adam Thean-Chor, Parameswari Namasivayam, Janna-Ong Abdullah, Ho, Chai-Ling
    The Pertanika Journal of Scholarly Research Reviews, 2018;4(2):1-17.
    MyJurnal
    Red seaweeds (Rhodophyta) produce a variety of sulfated galactans in their cell wall matrix and intercellular space, contributing up to 50-60 % of their total dry weight. These sulfated polysaccharides are made up of galactose disaccharides substituted with sulfate, methoxyl, pyruvic acid, or non-galactose monosaccharides (e.g. xylose, glucose and mannose). They are required by the Rhodophytes for protection against pathogen, desiccation, tidal waves and extreme changes in pH, temperature and salinity. Since ancient times, sulfated galactans from red seaweeds, such as agar and carrageenan, have been consumed as human foods and later being used in traditional medicine. Nowadays, some red seaweeds are cultivated and exploited for commercial uses in various fields. In this review, different types of sulfated galactans found in red seaweeds and their current and potential uses in food, biotechnology, medical and pharmaceutical industries are discussed.
    Matched MeSH terms: Polysaccharides
  18. Fulltext Association of Co-Morbidity and Treatment with the Complications of Acute Coronary Syndrome in Young Patients Less Than 45 Years
    Norsa'adah B, Che-Muzaini CM
    Malays J Med Sci, 2018 Feb;25(1):42-52.
    PMID: 29599634 MyJurnal DOI: 10.21315/mjms2018.25.1.6
    Background: Approximately 5%-10% of acute coronary syndrome (ACS) cases occur in people younger than 45 years of age. This study aimed to identify complications of ACS and the associated factors in young patients.

    Methods: In this cross-sectional study, data from 147 ACS patients aged less than 45 years were analysed.

    Results: The mean age was 39.1 (4.9) years, the male to female ratio was 3:1; 21.2% of patients presented with unstable angina, 58.5% had non-ST elevation myocardial infarction and 20.4% had ST elevation myocardial infarction. The most frequent risk factor of ACS was dyslipidaemia (65.3%), followed by hypertension (43.5%). In total, 49.7% of patients had inpatient complication(s), with the most common being heart failure (35.4%), followed by arrhythmia (20.4%). The significant factors associated with ACS complications were current smoking [adjusted odds ratio (AOR) 4.03; 95% confidence interval (CI): 1.33, 12.23;P-value = 0.014], diabetic mellitus [AOR 3.03; 95% CI: 1.19, 7.71;P-value = 0.020], treatments of fondaparinux [AOR 0.18; 95% CI: 0.08, 0.39;P-value < 0.001] and oral nitrates [AOR 0.18; 95% CI: 0.08, 0.42;P-value < 0.001].

    Conclusions: Smoking status and diabetes mellitus were modifiable risk factors while pharmacological treatment was an important protective factor for ACS complications in young patients.

    Matched MeSH terms: Polysaccharides
  19. Broad neutralization response in a subset of HIV-1 subtype C-infected viraemic non-progressors from southern India
    Nandagopal P, Bhattacharya J, Srikrishnan AK, Goyal R, Ravichandran Swathirajan C, Patil S, et al.
    J Gen Virol, 2018 Mar;99(3):379-392.
    PMID: 29458681 DOI: 10.1099/jgv.0.001016
    Broadly neutralizing antibodies (bnAbs) have been considered to be potent therapeutic tools and potential vaccine candidates to enable protection against various clades of human immunodeficiency virus (HIV). The generation of bnAbs has been associated with enhanced exposure to antigen, high viral load and low CD4+ T cell counts, among other factors. However, only limited data are available on the generation of bnAbs in viraemic non-progressors that demonstrate moderate to high viraemia. Further, since HIV-1 subtype C viruses account for more than 50 % of global HIV infections, the identification of bnAbs with novel specificities is crucial to enable the development of potent tools to aid in HIV therapy and prevention. In the present study, we analysed and compared the neutralization potential of responses in 70 plasma samples isolated from ART-naïve HIV-1 subtype C-infected individuals with various disease progression profiles against a panel of 30 pseudoviruses. Among the seven samples that exhibited a neutralization breadth of ≥70 %, four were identified as 'elite neutralizers', and three of these were from viraemic non-progressors while the fourth was from a typical progressor. Analysis of the neutralization specificities revealed that none of the four elite neutralizers were reactive to epitopes in the membrane proximal external region (MPER), CD4-binding site and V1V2 or V3 glycan. However, two of the four elite neutralizers exhibited enhanced sensitivity towards viruses lacking N332 glycan, indicating high neutralization potency. Overall, our findings indicate that the identification of potent neutralization responses with distinct epitope specificities is possible from the as yet unexplored Indian population, which has a high prevalence of HIV-1 subtype C infection.
    Matched MeSH terms: Polysaccharides
  20. Short report: Electron microscopic demonstration of extracellular structure of Burkholderia pseudomallei
    Puthucheary SD, Vadivelu J, Ce-Cile C, Kum-Thong W, Ismail G
    Am J Trop Med Hyg, 1996 Mar;54(3):313-4.
    PMID: 8600773
    The occurrence of latency and relapse in human melioidosis suggests adaptations by Burkholderia pseudomallei that help to avoid the human immune response. Ruthenium red-stained preparations of bacterial cultures viewed by electron microscopy revealed three morphologically distinct variants; one with a very marked and another with a less electron-dense layer surrounding the cell wall, and a third variety devoid of such a structure. This structure may be attributable to a layer of polysaccharide, suggesting the presence of a glycocalyx that may aid in the survival of the organism during latency.
    Matched MeSH terms: Polysaccharides/analysis; Polysaccharides/ultrastructure*
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