Displaying publications 41 - 60 of 160 in total

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  1. Ridwan R, Razak HRA, Adenan MI, Saad WMM
    Prev Nutr Food Sci, 2019 Mar;24(1):41-48.
    PMID: 31008095 DOI: 10.3746/pnf.2019.24.1.41
    Nutritional intervention of fruit juice supplementation is able to maximize exercise performance. Watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] contains high L-citrulline content and consumption of watermelon juice may promote ergogenic effects. The aim of the present study was to investigate the role of 100% flesh watermelon juice and 100% rind watermelon juice supplementation for 14 days on swimming performance in rats. Twenty four male Sprague-Dawley rats were randomly divided into four groups: Cx group of rats supplemented with filtered tap water (negative control), L-cit group of rats supplemented with L-citrulline (positive control), FR group of rats supplemented with 100% flesh watermelon juice, and RR group of rats supplemented with 100% rind watermelon juice. Each group was supplemented for 14 days ad libitum prior to swimming exercise protocol. The rats were performed swimming exercise for 3 days and swimming time until exhaustion was measured. Plasma samples were collected to measure lactate concentration, ammonia concentration, and nitric oxide production. Rats supplemented with 100% flesh watermelon juice demonstrated significantly prolonged of swimming time until exhaustion, reduction of lactate and ammonia concentrations, and increased of nitric oxide production compared to Cx and L-cit groups (P<0.05). These findings postulate that supplementation with 100% flesh watermelon juice improves endurance in swimming performance.
    Matched MeSH terms: Ammonia
  2. Rajendran R, Pandi A, Ramchary A, Thiagarajan H, Panneerselvam J, Niraikulam A, et al.
    Mol Biol Rep, 2019 Feb;46(1):133-141.
    PMID: 30374769 DOI: 10.1007/s11033-018-4453-8
    Urease is a potent metalloenzyme with diverse applications. This paper describes the scale up and purification of an extracellular urease from Arthrobacter creatinolyticus MTCC 5604. The urease production was scaled-up in 3.7 L and 20 L fermentor. A maximum activity of 27 and 27.8 U/mL and a productivity of 0.90 and 0.99 U/mL/h were obtained at 30 h and 28 h in 3.7 and 20 L fermentor, respectively. Urease was purified to homogeneity with 49.85-fold purification by gel filtration and anion exchange chromatography with a yield of 36% and a specific activity of 1044.37 U/mg protein. The enzyme showed three protein bands with molecular mass of 72.6, 11.2 and 6.1 kDa on SDS-PAGE and ~ 270 kDa on native PAGE. The cytotoxic effect of urease was assessed in vitro using cancer cell lines (A549 and MG-63) and normal cell line (HEK 293). Urease showed its inhibitory effects on cancer cell lines through the generation of toxic ammonia, which in turn increased the pH of the surrounding medium. This increase in extracellular pH, enhanced the cytotoxic effect of weak base chemotherapeutic drugs, doxorubicin (50 µM) and vinblastine (100 µM) in the presence of urease (5 U/mL) and urea (0-4 mM) significantly.
    Matched MeSH terms: Ammonia/metabolism
  3. Kumarn S, Churinthorn N, Nimpaiboon A, Sriring M, Ho CC, Takahara A, et al.
    Langmuir, 2018 10 30;34(43):12730-12738.
    PMID: 30335388 DOI: 10.1021/acs.langmuir.8b02321
    The stabilization mechanism of natural rubber (NR) latex from Hevea brasiliensis was studied to investigate the components involved in base-catalyzed ester hydrolysis, namely, hydrolyzable lipids, ammonia, and the products responsible for the desired phenomenon observed in ammonia-preserved NR latex. Latex stability is generally thought to come from a rubber particle (RP) dispersion in the serum, which is encouraged by negatively charged species distributed on the RP surface. The mechanical stability time (MST) and zeta potential were measured to monitor field latices preserved in high (FNR-HA) and low ammonia (FNR-LA) contents as well as that with the ester-containing components removed (saponified NR) at different storage times. Amounts of carboxylates of free fatty acids (FFAs), which were released by the transformation and also hypothesized to be responsible for the like-charge repulsion of RPs, were measured as the higher fatty acid (HFA) number and corroborated by confocal laser scanning microscopy (CLSM) both qualitatively and quantitatively. The lipids and their FFA products interact differently with Nile red, which is a lipid-selective and polarity-sensitive fluorophore, and consequently re-emit characteristically. The results were confirmed by conventional ester content determination utilizing different solvent extraction systems to reveal that the lipids hydrolyzed to provide negatively charged fatty acid species were mainly the polar lipids (glycolipids and phospholipids) at the RP membrane but not those directly linked to the rubber molecule and, to a certain extent, those suspended in the serum. From new findings disclosed herein together with those already reported, a new model for the Hevea rubber particle in the latex form is proposed.
    Matched MeSH terms: Ammonia
  4. Koyama M, Nagao N, Syukri F, Rahim AA, Kamarudin MS, Toda T, et al.
    Bioresour Technol, 2018 Oct;265:207-213.
    PMID: 29902653 DOI: 10.1016/j.biortech.2018.05.109
    Development of thermophilic composting for maximizing NH3 gas recovery would enable the production of a nitrogen source which is free from pathogen/heavy metal, for the cultivation of high-value microalgae. The present study examined the effect of NH3 recovery, nitrogen mass balance, and microbial community dynamics on thermophilic composting of shrimp aquaculture sludge. The emission of NH3 gas at 60 and 70 °C was 14.7% and 15.6%, respectively, which was higher than that at 50 °C (9.0%). The nitrogen mass balance analysis revealed that higher temperatures enhanced the solubilization of non-dissolved nitrogen and liberation of NH3 gas from the produced NH4+-N. High-throughput microbial community analysis revealed the shift of the dominant bacterial group from Bacillus to Geobacillus with the rise of composting temperature. In conclusion, thermophilic composting of shrimp aquaculture sludge at 60-70 °C was the most favorable condition for enhancing NH3 gas recovery.
    Matched MeSH terms: Ammonia
  5. Swamy MK, Sinniah UR, Ghasemzadeh A
    Appl Microbiol Biotechnol, 2018 Sep;102(18):7775-7793.
    PMID: 30022261 DOI: 10.1007/s00253-018-9223-y
    Rosmarinic acid (RA) is a highly valued natural phenolic compound that is very commonly found in plants of the families Lamiaceae and Boraginaceae, including Coleus blumei, Heliotropium foertherianum, Rosmarinus officinalis, Perilla frutescens, and Salvia officinalis. RA is also found in other members of higher plant families and in some fern and horned liverwort species. The biosynthesis of RA is catalyzed by the enzymes phenylalanine ammonia lyase and cytochrome P450-dependent hydroxylase using the amino acids tyrosine and phenylalanine. Chemically, RA can be produced via methods involving the esterification of 3,4-dihydroxyphenyllactic acid and caffeic acid. Some of the derivatives of RA include melitric acid, salvianolic acid, lithospermic acid, and yunnaneic acid. In plants, RA is known to have growth-promoting and defensive roles. Studies have elucidated the varied pharmacological potential of RA and its derived molecules, including anticancer, antiangiogenic, anti-inflammatory, antioxidant, and antimicrobial activities. The demand for RA is therefore, very high in the pharmaceutical industry, but this demand cannot be met by plants alone because RA content in plant organs is very low. Further, many plants that synthesize RA are under threat and near extinction owing to biodiversity loss caused by unscientific harvesting, over-collection, environmental changes, and other inherent features. Moreover, the chemical synthesis of RA is complicated and expensive. Alternative approaches using biotechnological methodologies could overcome these problems. This review provides the state of the art information on the chemistry, sources, and biosynthetic pathways of RA, as well as its anticancer properties against different cancer types. Biotechnological methods are also discussed for producing RA using plant cell, tissue, and organ cultures and hairy-root cultures using flasks and bioreactors. The recent developments and applications of the functional genomics approach and heterologous production of RA in microbes are also highlighted. This chapter will be of benefit to readers aiming to design studies on RA and its applicability as an anticancer agent.
    Matched MeSH terms: Phenylalanine Ammonia-Lyase
  6. Aziz HA, Puat NNA, Alazaiza MYD, Hung YT
    PMID: 30104522 DOI: 10.3390/ijerph15081734
    In this study, a sequential batch reactor (SBR) with different types of fibers was employed for the treatment of poultry slaughterhouse wastewater. Three types of fibers, namely, juite fiber (JF), bio-fringe fiber (BF), and siliconised conjugated polyester fiber (SCPF), were used. Four SBR experiments were conducted, using the fibers in different reactors, while the fourth reactor used a combination of these fibers. The treatment efficiency of the different reactors with and without fibers on biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonia-nitrogen (NH₃-N), phosphorus (P), nitrite (NO₂), nitrate (NO₃), total suspended solids (TSS), and oil-grease were evaluated. The removal efficiency for the reactors with fibers was higher than that of the reactor without fibers for all pollutants. The treated effluent had 40 mg/L BOD₅ and 45 mg/L COD with an average removal efficiency of 96% and 93%, respectively, which meet the discharge limits stated in the Environmental Quality Act in Malaysia.
    Matched MeSH terms: Ammonia
  7. Er HH, Lee LK, Lim ZF, Teng ST, Leaw CP, Lim PT
    Environ Sci Pollut Res Int, 2018 Aug;25(23):22944-22962.
    PMID: 29858995 DOI: 10.1007/s11356-018-2389-0
    Effects of aquaculture activities on the environmental parameters and phytoplankton community structure were investigated in a semi-enclosed lagoon located at Semerak River, Malaysia. Elevated concentrations of phosphate and ammonia were observed at the aquaculture area and the inner lagoon. Relatively low dissolved oxygen, high total chlorophyll a, and high phytoplankton abundances but low species richness were recorded. Chaetoceros, Pseudo-nitzschia brasiliana, Blixaea quinquecornis, and Skeletonema blooms were observed, and some were associated with anoxia condition. Eutrophication level assessed by UNTRIX suggests that the water quality in the lagoon is deteriorating. Dissolved inorganic phosphorus and nitrogen at the impacted area were 15 and 12 times higher than the reference sites, respectively. Such trophic status indices could provide a useful guideline for optimal aquaculture management plan to reduce the environmental impact caused by aquaculture.
    Matched MeSH terms: Ammonia/analysis
  8. Arij Y, Fatihah S, Rakmi AR
    Bioresour Technol, 2018 Jul;260:213-220.
    PMID: 29626780 DOI: 10.1016/j.biortech.2018.03.131
    The anaerobic treatment of leachate from a municipal waste transfer station in Malaysia was tested using a pilot scale anaerobic biofilm digester system that was operated under HRT sequence of 30-day, 25-day, 20-day and 10-day for 163 days under mesophilic conditions. Despite the leachate's complex characteristics, the system showed great performance given its maximum COD, BOD5 and total phosphorus removal efficiencies of 98 ± 1%, 99 ± 1% and 92 ± 9% respectively. The system was stable throughout its operation and showed optimal average values for the monitored parameters such as pH (7.53 ± 0.14), total VFA (79 ± 66 mg HOAc/L), alkalinity (10,919 ± 1556 mg CaCO3/L) and a non-toxic value for accumulated ammonia (960 ± 106 mg NH3-N/L). Measurement of the average daily biogas production yielded a value of 25 ± 1 m3/day throughout the system's operation with a composition of 57 ± 12% methane and 26 ± 6% carbon dioxide.
    Matched MeSH terms: Ammonia
  9. Palomo A, Pedersen AG, Fowler SJ, Dechesne A, Sicheritz-Pontén T, Smets BF
    ISME J, 2018 06;12(7):1779-1793.
    PMID: 29515170 DOI: 10.1038/s41396-018-0083-3
    The description of comammox Nitrospira spp., performing complete ammonia-to-nitrate oxidation, and their co-occurrence with canonical β-proteobacterial ammonia oxidizing bacteria (β-AOB) in the environment, calls into question the metabolic potential of comammox Nitrospira and the evolutionary history of their ammonia oxidation pathway. We report four new comammox Nitrospira genomes, constituting two novel species, and the first comparative genomic analysis on comammox Nitrospira. Unlike canonical Nitrospira, comammox Nitrospira genomes lack genes for assimilatory nitrite reduction, suggesting that they have lost the potential to use external nitrite nitrogen sources. By contrast, compared to canonical Nitrospira, comammox Nitrospira harbor a higher diversity of urea transporters and copper homeostasis genes and lack cyanate hydratase genes. Additionally, the two comammox clades differ in their ammonium uptake systems. Contrary to β-AOB, comammox Nitrospira genomes have single copies of the two central ammonia oxidation pathway operons. Similar to ammonia oxidizing archaea and some oligotrophic AOB strains, they lack genes involved in nitric oxide reduction. Furthermore, comammox Nitrospira genomes encode genes that might allow efficient growth at low oxygen concentrations. Regarding the evolutionary history of comammox Nitrospira, our analyses indicate that several genes belonging to the ammonia oxidation pathway could have been laterally transferred from β-AOB to comammox Nitrospira. We postulate that the absence of comammox genes in other sublineage II Nitrospira genomes is the result of subsequent loss.
    Matched MeSH terms: Ammonia/metabolism*
  10. Aziz HA, Razak MHA, Rahim MZA, Kamar WISW, Abu Amr SS, Hussain S, et al.
    Data Brief, 2018 Jun;18:920-927.
    PMID: 29900259 DOI: 10.1016/j.dib.2018.03.113
    Wastewater treatment is a key challenge in the textile industry. The current treatment methods for textile wastewater are insufficient or ineffective for complex dyes generated from the textile industry. This study evaluated the performances of two novel inorganic coagulants with high cationic charges, namely, titanium tetrachloride (TiCl4) and zirconium tetrachloride (ZrCl4). They were utilised to treat textile industry wastewater. Both coagulation processes were performed under the same experimental operational conditions. Turbidity, suspended solids (SS), colour, chemical oxygen demand (COD) and ammonia were measured to assess the efficiencies of the coagulants. Results indicated that ZrCl4 and TiCl4 exhibited high potentials for textile wastewater treatment. ZrCl4 presented high removal efficiency in COD and SS, whereas TiCl4 showed excellent removal in ammonia.
    Matched MeSH terms: Ammonia
  11. Goh KM, Dickinson M, Supramaniam CV
    Physiol Plant, 2018 Mar;162(3):274-289.
    PMID: 28940509 DOI: 10.1111/ppl.12645
    Lignification of the plant cell wall could serve as the first line of defense against pathogen attack, but the molecular mechanisms of virulence and disease between oil palm and Ganoderma boninense are poorly understood. This study presents the biochemical, histochemical, enzymology and gene expression evidences of enhanced lignin biosynthesis in young oil palm as a response to G. boninense (GBLS strain). Comparative studies with control (T1), wounded (T2) and infected (T3) oil palm plantlets showed significant accumulation of total lignin content and monolignol derivatives (syringaldehyde and vanillin). These derivatives were deposited on the epidermal cell wall of infected plants. Moreover, substantial differences were detected in the activities of enzyme and relative expressions of genes encoding phenylalanine ammonia lyase (EC 4.3.1.24), cinnamate 4-hydroxylase (EC 1.14.13.11), caffeic acid O-methyltransferase (EC 2.1.1.68) and cinnamyl alcohol dehydrogenase (CAD, EC 1.1.1.195). These enzymes are key intermediates dedicated to the biosynthesis of lignin monomers, the guaicyl (G), syringyl (S) and ρ-hydroxyphenyl (H) subunits. Results confirmed an early, biphasic and transient positive induction of all gene intermediates, except for CAD enzyme activities. These differences were visualized by anatomical and metabolic changes in the profile of lignin in the oil palm plantlets such as low G lignin, indicating a potential mechanism for enhanced susceptibility toward G. boninense infection.
    Matched MeSH terms: Phenylalanine Ammonia-Lyase/genetics; Phenylalanine Ammonia-Lyase/metabolism
  12. Yusuf CYL, Abdullah JO, Shaharuddin NA, Abu Seman I, Abdullah MP
    Plant Cell Rep, 2018 Feb;37(2):265-278.
    PMID: 29090330 DOI: 10.1007/s00299-017-2228-7
    KEY MESSAGE: The oil palm EgPAL1 gene promoter and its regulatory region were functional as a promoter in the heterologous system of Arabidopsis according to the cis-acting elements present in that region. The promoter was developmentally regulated, vascular tissue specific and responsive to water stress agents. Phenylalanine ammonia lyase (PAL, EC 4.3.1.24) is the key enzyme of the phenylpropanoid pathway which plays important roles in plant development and adaptation. To date, there is no report on the study of PAL from oil palm (Elaeis guineensis), an economically important oil crop. In this study, the 5' regulatory sequence of a highly divergent oil palm PAL gene (EgPAL1) was isolated and fused with GUS in Arabidopsis to create two transgenic plants carrying the minimal promoter with (2302 bp) and without its regulatory elements (139 bp). The regulatory sequence contained cis-acting elements known to be important for plant development and stress response including the AC-II element for lignin biosynthesis and several stress responsive elements. The promoter and its regulatory region were fully functional in Arabidopsis. Its activities were characterised by two common fundamental features of PAL which are responsive to plant internal developmental programme and external factors. The promoter was developmentally regulated in certain organs; highly active in young organs but less active or inactive in mature organs. The presence of the AC elements and global activity of the EgPAL1 promoter in all organs resembled the property of lignin-related genes. The existence of the MBS element and enhancement of the promoter activity by PEG reflected the behaviour of drought-responsive genes. Our findings provide a platform for evaluating oil palm gene promoters in the heterologous system of Arabidopsis and give insights into the activities of EgPAL1 promoter in oil palm.
    Matched MeSH terms: Phenylalanine Ammonia-Lyase/classification; Phenylalanine Ammonia-Lyase/genetics*
  13. Khan MF, Maulud KNA, Latif MT, Chung JX, Amil N, Alias A, et al.
    Sci Total Environ, 2018 Feb 01;613-614:1401-1416.
    PMID: 29898507 DOI: 10.1016/j.scitotenv.2017.08.025
    Air pollution can be detected through rainwater composition. In this study, long-term measurements (2000-2014) of wet deposition were made to evaluate the physicochemical interaction and the potential sources of pollution due to changes of land use. The rainwater samples were obtained from an urban site in Kuala Lumpur and a highland-rural site in the middle of Peninsular Malaysia. The compositions of rainwater were obtained from the Malaysian Meteorological Department. The results showed that the urban site experienced more acidity in rainwater (avg=277mm, range of 13.8 to 841mm; pH=4.37) than the rural background site (avg=245mm, range of 2.90 to 598mm; pH=4.97) due to higher anthropogenic input of acid precursors. The enrichment factor (EF) analysis showed that at both sites, SO42-, Ca2+ and K+ were less sensitive to seawater but were greatly influenced by soil dust. NH4+ and Ca2+ can neutralise a larger fraction of the available acid ions in the rainwater at the urban and rural background sites. However, acidifying potential was dominant at urban site compared to rural site. Source-receptor relationship via positive matrix factorisation (PMF 5.0) revealed four similar major sources at both sites with a large variation of the contribution proportions. For urban, the major sources influence on the rainwater chemistry were in the order of secondary nitrates and sulfates>ammonium-rich/agricultural farming>soil components>marine sea salt and biomass burning, while at the background site the order was secondary nitrates and sulfates>marine sea salt and biomass burning=soil components>ammonia-rich/agricultural farming. The long-term trend showed that anthropogenic activities and land use changes have greatly altered the rainwater compositions in the urban environment while the seasonality strongly affected the contribution of sources in the background environment.
    Matched MeSH terms: Ammonia
  14. Manogaran M, Shukor MY, Yasid NA, Khalil KA, Ahmad SA
    3 Biotech, 2018 Feb;8(2):108.
    PMID: 29430369 DOI: 10.1007/s13205-018-1123-4
    The herbicide glyphosate is often used to control weeds in agricultural lands. However, despite its ability to effectively kill weeds at low cost, health problems are still reported due to its toxicity level. The removal of glyphosate from the environment is usually done by microbiological process since chemical process of degradation is ineffective due to the presence of highly stable bonds. Therefore, finding glyphosate-degrading microorganisms in the soil of interest is crucial to remediate this glyphosate.Burkholderia vietnamiensisstrain AQ5-12 was found to have glyphosate-degrading ability. Optimisation of biodegradation condition was carried out utilising one factor at a time (OFAT) and response surface methodology (RSM). Five parameters including carbon and nitrogen source, pH, temperature and glyphosate concentration were optimised. Based on OFAT result, glyphosate degradation was observed to be optimum at fructose concentration of 6, 0.5 g/L ammonia sulphate, pH 6.5, temperature of 32 °C and glyphosate concentration at 100 ppm. Meanwhile, RSM resulted in a better degradation with 92.32% of 100 ppm glyphosate compared to OFAT. The bacterium was seen to tolerate up to 500 ppm glyphosate while increasing concentration results in reduced degradation and bacterial growth rate.
    Matched MeSH terms: Ammonia
  15. Moradihamedani P, Abdullah AH
    Water Sci Technol, 2018 Jan;77(1-2):346-354.
    PMID: 29377819 DOI: 10.2166/wst.2017.545
    Removal of low-concentration ammonia (1-10 ppm) from aquaculture wastewater was investigated via polysulfone (PSf)/zeolite mixed matrix membrane. PSf/zeolite mixed matrix membranes with different weight ratios (90/10, 80/20, 70/30 and 60/40 wt.%) were prepared and characterized. Results indicate that PSf/zeolite (80/20) was the most efficient membrane for removal of low-concentration ammonia. The ammonia elimination by PSf/zeolite (80/20) from aqueous solution for 10, 7, 5, 3 and 1 ppm of ammonia was 100%, 99%, 98.8%, 96% and 95% respectively. The recorded results revealed that pure water flux declined in higher loading of zeolite in the membrane matrix due to surface pore blockage caused by zeolite particles. On the other hand, ammonia elimination from water was decreased in higher contents of zeolite because of formation of cavities and macrovoids in the membrane substructure.
    Matched MeSH terms: Ammonia/analysis*; Ammonia/chemistry
  16. Azizah Endut, Fathurrahman Lananan, Ahmad Jusoh, Wan Norsani Wan Nik, Nora'aini Ali
    MyJurnal
    The current and escalating extent of soil degradation, water scarcity and environmental concern
    plaguing agricultural productivity, demands re-assessing the direction of food production. Aquaponics
    is a concept relatively new to modern food production methods and can contribute to food security.
    This study was conducted to establish sustainable aquaculture systems that maximize benefits and
    minimize the accumulation of detrimental compounds and other types of negative impacts on both
    natural and social environments. This study carried out at an average inflow rate of 1.28 m/day to
    evaluate the operation of the aquaponics recirculation system (ARS) on nutrients removal and growth
    and yield of African catfish as well as water spinach. A special design of ARS was used to provide
    nitrification of fishery wastewater, where the combination of sands and gravels in hydroponics trough,
    providing both surfaces for biofuel development and cultivation area for plants. Removal efficiencies
    of 5-day biochemical oxygen demand (BOD5), total suspended solids (TSS), total ammonia nitrogen
    (TAN), nitrite-nitrogen (NO2-N), nitrate-nitrogen (NO3-N), and orthophosphate (PO4
    3-
    ) were 82%, 89%,
    93%, 94%, 81%, and 80%, respectively. The feed conversion ratio (FCR) and specific growth rate
    (SGR) of African catfish were 1.08 and 3.34% day-1
    , respectively. The average water spinach
    production was 3.56 kg per m2
    . This study showed that ARS is a method of producing crop along with
    a healthy protein source and among the best alternatives for achieving economic and environmental
    sustainability.
    Matched MeSH terms: Ammonia
  17. Nur Nazlina Saimon, Heng Khuan Eu, Anwar Johari, Norzita Ngadi, Mazura Jusoh, Zaki Yamani Zakaria
    Sains Malaysiana, 2018;47:109-115.
    Biodiesel, one of the renewable energy sources has gained attention for decades as the alternative fuel due to its remarkable properties. However, there are several drawbacks from the industrial production of biodiesel such as the spike in the production cost, environmental issues related to the usage of homogeneous catalyst and profitability in long term. One of the solutions to eliminate the problem is by utilizing low cost starting material such as palm fatty acid distillate (PFAD). PFAD is a byproduct from the refining of crude palm oil and abundantly available. Esterification of PFAD to biodiesel will be much easier with the presence of heterogeneous acid catalyst. Most of acid catalyst preparation involves series of heating process using conventional method. In this study, microwave was utilized in catalyst preparation, significantly reducing the reaction time from conventional heating method. The catalyst produced was characterized using X-Ray Diffraction (XRD), Brunauer Emmet and Teller (BET), Scanning Electron Microscopy (SEM), Temperature-Programmed Desorption - Ammonia (TPD-NH3) and Fourier Transform Infrared (FTIR) while percentage yield and conversion of the PFAD were analysed by gas chromatography - flame ionization detector (GC-FID) and acid-base titration, respectively. It has been demonstrated that the percentage yield of biodiesel from the PFAD by employing sulfonated glucose acid catalyst (SGAC) reached 98.23% under the following conditions: molar ratio of methanol to PFAD of 10:1, catalyst loading of 2.5% and reaction temperature of 70oC. The microwave-assisted SGAC showed its potential to replace the SGAC produced via conventional heating method.
    Matched MeSH terms: Ammonia
  18. J.Karim, M.A.M.Idrus, N.H.F.Hashim, M.Abdullah, S.S.Sharifuddin, M.F.Muhazeli, et al.
    MyJurnal
    Rivers as surface water in Malaysia are recipients of effluents and wastewater and yet it is important water source for daily uses of some villagers living along the river. Endocrine disruptors such as Bisphenol A (BPA) can be found in river due to continuous discharge into it. The objectives of this research is to find out the occurrence and concentration of BPA in Sungai Langat and also to see how water quality parameters such as temperature, pH, dissolved oxygen (DO), turbidity, Total Suspended Solid (TSS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and ammonia nitrogen (AN) affecting the concentration of BPA. 12 stations in total including upstream to downstream of Sungai Langat and also tributary of Sungai Langat. The instrument used to find out concentration of BPA is Triple Quadrupole LC/MS. The source of BPA are mainly industrial effluents and also direct domestic discharges. The water quality parameters that will affect concentration of BPA are Ammonia Nitrogen (AN), turbidity, Biochemical Oxygen Demand (BOD), Total Suspended Solid (TSS), and Chemical Oxygen Demand (COD), Dissolved Oxygen (DO). While pH and water temperature are also factors that will affect concentration of BPA but the significance is not shown in the analysis. It can be concluded that upstream of Sungai Langat has lower concentration of BPA than downstream.
    Matched MeSH terms: Ammonia
  19. Mohamed Ramli N, Giatsis C, Md Yusoff F, Verreth J, Verdegem M
    PLoS One, 2018;13(4):e0195862.
    PMID: 29659617 DOI: 10.1371/journal.pone.0195862
    The experimental set-up of this study mimicked recirculating aquaculture systems (RAS) where water quality parameters such as dissolved oxygen, pH, temperature, and turbidity were controlled and wastes produced by fish and feeding were converted to inorganic forms. A key process in the RAS was the conversion of ammonia to nitrite and nitrite to nitrate through nitrification. It was hypothesized that algae inclusion in RAS would improve the ammonia removal from the water; thereby improving RAS water quality and stability. To test this hypothesis, the stability of the microbiota community composition in a freshwater RAS with (RAS+A) or without algae (RAS-A) was challenged by introducing an acute pH drop (from pH 7 to 4 during three hours) to the system. Stigeoclonium nanum, a periphytic freshwater microalga was used in this study. No significant effect of the algae presence was found on the resistance to the acute pH drop on ammonia conversion to nitrite and nitrite conversion to nitrate. Also the resilience of the ammonia conversion to the pH drop disruption was not affected by the addition of algae. This could be due to the low biomass of algae achieved in the RAS. However, with regard to the conversion step of nitrite to nitrate, RAS+A was significantly more resilient than RAS-A. In terms of overall bacterial communities, the composition and predictive function of the bacterial communities was significantly different between RAS+A and RAS-A.
    Matched MeSH terms: Ammonia/chemistry
  20. Abdul Rohim Tualeka, Juliana Jalaludin
    MyJurnal
    The production of ammonia has been increasing over the past few years. Unfortunately, the production does not follow the safety control of ammonia on workers. Indonesia still adopts chemical standard from other countries. Therefore, it requires an ammonia standard at the highest dose without effect or no observed adverse effect level (NOAEL) in the workplace. This research aims to determine standard at the highest dose of without effect through the expression of CD8 cells as well as analysis of histological alteration CD8 lymphocyte between exposed to ammonia group and control. Methods: The study was a laboratory experimental research with a post-test only control group design. The research used Rattus novergicus species as many as 24. NOAEL was determined by middle dose with a location between the smallest and the largest dose. The doses of ammonia were given through inhalation. The histological alteration of CD8 between ammonia in exposed and the control group were analyzed by using the Kruskal Wallis test. Results: NOAEL was found through CD8 located in group 3 with 0.0154 dose mg/kg body weight. There was a differential expression of CD8 lymphocyte cells in the white mice lung between exposed to ammonia group and control (p=0.042). Conclusion: The expression of CD8 lymphocyte cells in the white mice lung exposed to ammonia differs significantly with the number of the expression of CD8 lymphocyte cells in white mice lung at control group. NOAEL was 0.0154 mg/kg body weight of white mice.
    Matched MeSH terms: Ammonia
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