Displaying publications 21 - 40 of 122 in total

Abstract:
Sort:
  1. See-Too WS, Ambrose M, Malley R, Ee R, Mulcahy E, Manche E, et al.
    Int J Syst Evol Microbiol, 2019 Mar;69(3):645-651.
    PMID: 30676309 DOI: 10.1099/ijsem.0.003147
    Pandoraea species have been isolated from diverse environmental samples and are emerging important respiratory pathogens, particularly in people with cystic fibrosis (CF). In the present study, two bacterial isolates initially recovered from consecutive sputum samples collected from a CF patient and identified as Pandoraea pnomenusa underwent a polyphasic taxonomic analysis. The isolates were found to be Gram-negative, facultative anaerobic motile bacilli and subsequently designated as strains 6399T (=LMG29626T=DSM103228T) and 7641 (=LMG29627=DSM103229), respectively. Phylogenetic analysis based on 16S rRNA and gyrB gene sequences revealed that 6399T and 7641 formed a distinct phylogenetic lineage within the genus Pandoraea. Genome sequence comparison analysis indicated that strains 6399T and 7641 are clonal and share 100 % similarity, however, similarity to other type strains (ANIb 73.2-88.8 %, ANIm 83.5-89.9 % and OrthoANI 83.2-89.3 %) indicates that 6399T and 7641 do not belong to any of the reported type species. The major cellular fatty acids of 6399T were C16 : 0 (32.1 %) C17 : 0cyclo (18.7 %) and C18 : 1ω7c (14.5 %), while Q-8 was the only respiratory quinone detected. The major polar lipids identified were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The genomic DNA G+C content of 6399T was 62.9 (mol%). Strain 6399T can be differentiated from other members of Pandoraea by the absence of C19 : 0ω8c cyclo and by the presence of C17 : 0ω8c cyclo. Together our data show that the bacterial strains 6399T and 7641 represent a novel species of the genus Pandoraea, for which the name Pandoraea fibrosis sp. nov. is proposed (type strain 6399T).
    Matched MeSH terms: Anaerobiosis
  2. Zakaria SNF, Aziz HA, Mohamad M, Mohamad HM, Sulaiman MF
    Water Environ Res, 2023 Nov;95(11):e10941.
    PMID: 37828655 DOI: 10.1002/wer.10941
    Malaysia encounters a consistent rise in the generation of solid waste and leachate on a daily basis. It should also be noted that leachate has a low degree of biodegradability (BOD5 /chemical oxygen demand [COD]), as shown by its BOD5 /COD ratio. Its high toxicity levels significantly threaten the environment, water bodies, and human well-being. High concentrations of COD, color, and ammoniacal nitrogen (NH3 -N) in leachate prevent this wastewater from being allowed to be discharged directly into the water body. Therefore, an effective process to remove the pollutant is desired. The aims of this study are to investigate the performance of ozonation with two metallic compounds, ZrCl4 and SnCl4 , and optimize their performance using response surface methodology (RSM). In this study, the performance of ozonation with ZrCl4 (O3 /ZrCl4 ) recorded better pollutant removals compared with the ozonation with tin tetrachloride (O3 /SnCl4 ), as seen in the removals of 99.8%, 93.5%, and 46.3% for color, COD, and NH3 -N, respectively. These removals were achieved by following the experimental model (optimum experiment condition) generated by RSM at O3 dosage of 31 g/m3 , COD and ZrCl4 dosage ratio (COD, mg/L/ZrCl4 , mg/L) of 1:1.35, with the pH solution of 8.78 and reaction time of 89 min. The R2 of each parameter for this model was recorded as 0.999 (COD), 0.999 (color), and 0.998 (NH3 -N), respectively. These data indicated that the model is well fitted as the predicted data by statistical calculation and in good agreement with the actual data. PRACTITIONER POINTS: The performance of O3 /ZrCl4 and O3 /SnCl4 was examined for remediate stabilized landfill leachate. The performance of O3 /ZrCl4 and O3 /SnCl4 was optimized using RSM, and a set of experimental models was generated and tested. O3 /ZrCl4 recorded the higher removal of COD, color, and NH3 -N compared with O3 /SnCl4 . At best condition, both methods recorded removal as 89% to 99.8% of pollutants in leachate and product clear effluent. This finding gives a new approach to treat landfill leachate effectively and efficiently.
    Matched MeSH terms: Anaerobiosis
  3. Aida AA, Hatamoto M, Yamamoto M, Ono S, Nakamura A, Takahashi M, et al.
    J Biosci Bioeng, 2014 Nov;118(5):540-5.
    PMID: 24930844 DOI: 10.1016/j.jbiosc.2014.04.011
    A novel wastewater treatment system consisting of an up-flow anaerobic sludge blanket (UASB) reactor and a down-flow hanging sponge (DHS) reactor with sulfur-redox reaction was developed for treatment of municipal sewage under low-temperature conditions. In the UASB reactor, a novel phenomenon of anaerobic sulfur oxidation occurred in the absence of oxygen, nitrite and nitrate as electron acceptors. The microorganisms involved in anaerobic sulfur oxidation have not been elucidated. Therefore, in this study, we studied the microbial communities existing in the UASB reactor that probably enhanced anaerobic sulfur oxidation. Sludge samples collected from the UASB reactor before and after sulfur oxidation were used for cloning and terminal restriction fragment length polymorphism (T-RFLP) analysis of the 16S rRNA genes of the bacterial and archaeal domains. The microbial community structures of bacteria and archaea indicated that the genus Smithella and uncultured bacteria within the phylum Caldiserica were the dominant bacteria groups. Methanosaeta spp. was the dominant group of the domain archaea. The T-RFLP analysis, which was consistent with the cloning results, also yielded characteristic fingerprints for bacterial communities, whereas the archaeal community structure yielded stable microbial community. From these results, it can be presumed that these major bacteria groups, genus Smithella and uncultured bacteria within the phylum Caldiserica, probably play an important role in sulfur oxidation in UASB reactors.
    Matched MeSH terms: Anaerobiosis
  4. Mienda BS, Shamsir MS, Illias RM
    Comput Biol Chem, 2016 Apr;61:130-7.
    PMID: 26878126 DOI: 10.1016/j.compbiolchem.2016.01.013
    The metabolic role of 6-phosphogluconate dehydrogenase (gnd) under anaerobic conditions with respect to succinate production in Escherichia coli remained largely unspecified. Herein we report what are to our knowledge the first metabolic gene knockout of gnd to have increased succinic acid production using both glucose and glycerol substrates in E. coli. Guided by a genome scale metabolic model, we engineered the E. coli host metabolism to enhance anaerobic production of succinic acid by deleting the gnd gene, considering its location in the boundary of oxidative and non-oxidative pentose phosphate pathway. This strategy induced either the activation of malic enzyme, causing up-regulation of phosphoenolpyruvate carboxylase (ppc) and down regulation of phosphoenolpyruvate carboxykinase (ppck) and/or prevents the decarboxylation of 6 phosphogluconate to increase the pool of glyceraldehyde-3-phosphate (GAP) that is required for the formation of phosphoenolpyruvate (PEP). This approach produced a mutant strain BMS2 with succinic acid production titers of 0.35gl(-1) and 1.40gl(-1) from glucose and glycerol substrates respectively. This work further clearly elucidates and informs other studies that the gnd gene, is a novel deletion target for increasing succinate production in E. coli under anaerobic condition using glucose and glycerol carbon sources. The knowledge gained in this study would help in E. coli and other microbial strains development for increasing succinate production and/or other industrial chemicals.
    Matched MeSH terms: Anaerobiosis
  5. Ahmad A, Ghufran R
    Crit Rev Biotechnol, 2023 Dec;43(8):1236-1256.
    PMID: 36130802 DOI: 10.1080/07388551.2022.2103641
    This critical review for anaerobic degradation of complex organic compounds like butyrate using reactors has been enormously applied for biogas production. Biogas production rate has a great impact on: reactor granulation methanogenesis, nutrient content, shear velocity, organic loading and loss of nutrients taking place in the reactor continuously. Various technologies have been applied to closed anaerobic reactors to improve biogas production and treatment efficiency. Recent reviews showed that the application of closed anaerobic reactors can accelerate the degradation of organics like volatile fatty acid-butyrate and affect microbial biofilm formation by increasing the number of methanogens and increase methane production 16.5 L-1 CH4 L-1 POME-1. The closed anaerobic reactors with stable microbial biofilm and established organic load were responsible for the improvement of the reactor and methane production. The technology mentioned in this review can be used to monitor biogas concentration, which directly correlates to organic concentrations. This review attempts to evaluate interactions among the: degradation of organics, closed anaerobic reactors system, and microbial granules. This article provides a useful picture for the improvement of the degradation of organic butyrate for COD removal, biogas and methane production in an anaerobic closed reactor.
    Matched MeSH terms: Anaerobiosis
  6. Xiao SS, Mi JD, Mei L, Liang J, Feng KX, Wu YB, et al.
    Animals (Basel), 2021 Mar 16;11(3).
    PMID: 33809729 DOI: 10.3390/ani11030840
    The intestinal microbiota is increasingly recognized as an important component of host health, metabolism and immunity. Early gut colonizers are pivotal in the establishment of microbial community structures affecting the health and growth performance of chickens. White Lohmann layer is a common commercial breed. Therefore, this breed was selected to study the pattern of changes of microbiota with age. In this study, the duodenum, caecum and colorectum contents of white Lohmann layer chickens from same environment control farm were collected and analyzed using 16S rRNA sequencing to explore the spatial and temporal variations in intestinal microbiota. The results showed that the diversity of the microbial community structure in the duodenum, caecum and colorectum increased with age and tended to be stable when the layer chickens reached 50 days of age and the distinct succession patterns of the intestinal microbiota between the duodenum and large intestine (caecum and colorectum). On day 0, the diversity of microbes in the duodenum was higher than that in the caecum and colorectum, but the compositions of intestinal microbes were relatively similar, with facultative anaerobic Proteobacteria as the main microbes. However, the relative abundance of facultative anaerobic bacteria (Escherichia) gradually decreased and was replaced by anaerobic bacteria (Bacteroides and Ruminococcaceae). By day 50, the structure of intestinal microbes had gradually become stable, and Lactobacillus was the dominant bacteria in the duodenum (41.1%). The compositions of dominant microbes in the caecum and colorectum were more complex, but there were certain similarities. Bacteroides, Odoribacter and Clostridiales vadin BB60 group were dominant. The results of this study provide evidence that time and spatial factors are important factors affecting the intestinal microbiota composition. This study provides new knowledge of the intestinal microbiota colonization pattern of layer chickens in early life to improve the intestinal health of layer chickens.
    Matched MeSH terms: Anaerobiosis
  7. Sekine M, Yoshida A, Akizuki S, Kishi M, Toda T
    Water Sci Technol, 2020 Sep;82(6):1070-1080.
    PMID: 33055397 DOI: 10.2166/wst.2020.153
    A novel coupling process using an aerobic bacterial reactor with nitrification and sulfur-oxidization functions followed by a microalgal reactor was proposed for simultaneous biogas desulfurization and anaerobic digestion effluent (ADE) treatment. ADE nitrified by bacteria has a potential to be directly used as a culture medium for microalgae because ammonium nitrogen, including inhibitory free ammonia (NH3), has been converted to harmless NO3-. To demonstrate this hypothesis, Chlorella sorokiniana NIES-2173, which has ordinary NH3 tolerance; that is, 1.6 mM of EC50 compared with other species, was cultivated using untreated/treated ADE. Compared with the use of a synthetic medium, when using ADE with 1-10-fold dilutions, the specific growth rate and growth yield maximally decreased by 44% and 88%, respectively. In contrast, the algal growth using undiluted ADE treated by nitrification-desulfurization was almost the same as with using synthetic medium. It was also revealed that 50% of PO43- and most metal concentrations of ADE decreased following nitrification-desulfurization treatment. Moreover, upon NaOH addition for pH adjustment, the salinity increased to 0.66%. The decrease in metals mitigates the bioconcentration of toxic heavy metals from wastewater in microalgal biomass. Meanwhile, salt stress in microalgae and limiting nutrient supplementation, particularly for continuous cultivation, should be of concern.
    Matched MeSH terms: Anaerobiosis
  8. Moset V, Poulsen M, Wahid R, Højberg O, Møller HB
    Microb Biotechnol, 2015 Sep;8(5):787-800.
    PMID: 25737010 DOI: 10.1111/1751-7915.12271
    In this study, productivity and physicochemical and microbiological (454 sequencing) parameters, as well as environmental criteria, were investigated in anaerobic reactors to contribute to the ongoing debate about the optimal temperature range for treating animal manure, and expand the general knowledge on the relation between microbiological and physicochemical process indicators. For this purpose, two reactor sizes were used (10 m(3) and 16 l), in which two temperature conditions (35°C and 50°C) were tested. In addition, the effect of the hydraulic retention time was evaluated (16 versus 20 days). Thermophilic anaerobic digestion showed higher organic matter degradation (especially fiber), higher pH and higher methane (CH₄) yield, as well as better percentage of ultimate CH₄ yield retrieved and lower residual CH₄ emission, when compared with mesophilic conditions. In addition, lower microbial diversity was found in the thermophilic reactors, especially for Bacteria, where a clear intensification towards Clostridia class members was evident. Independent of temperature, some similarities were found in digestates when comparing with animal manure, including low volatile fatty acids concentrations and a high fraction of Euryarchaeota in the total microbial community, in which members of Methanosarcinales dominated for both temperature conditions; these indicators could be considered a sign of process stability.
    Matched MeSH terms: Anaerobiosis
  9. Ong YH, Chua AS, Lee BP, Ngoh GC
    Water Sci Technol, 2013;67(2):340-6.
    PMID: 23168633 DOI: 10.2166/wst.2012.552
    To date, little information is known about the operation of the enhanced biological phosphorus removal (EBPR) process in tropical climates. Along with the global concerns on nutrient pollution and the increasing array of local regulatory requirements, the applicability and compliance accountability of the EBPR process for sewage treatment in tropical climates is being evaluated. A sequencing batch reactor (SBR) inoculated with seed sludge from a conventional activated sludge (CAS) process was successfully acclimatized to EBPR conditions at 28 °C after 13 days' operation. Enrichment of Candidatus Accumulibacter phosphatis in the SBR was confirmed through fluorescence in situ hybridization (FISH). The effects of operational pH and influent C:P ratio on EBPR were then investigated. At pH 7 or pH 8, phosphorus removal rates of the EBPR processes were relatively higher when operated at C:P ratio of 3 than C:P ratio of 10, with 0.019-0.020 and 0.011-0.012 g-P/g-MLVSS•day respectively. One-year operation of the 28 °C EBPR process at C:P ratio of 3 and pH 8 demonstrated stable phosphorus removal rate of 0.020 ± 0.003 g-P/g-MLVSS•day, corresponding to effluent with phosphorus concentration <0.5 mg/L. This study provides the first evidence on good EBPR activity at relatively high temperature, indicating its applicability in a tropical climate.
    Matched MeSH terms: Anaerobiosis
  10. Aziz SQ, Aziz HA, Yusoff MS, Bashir MJ, Umar M
    J Environ Manage, 2010 Dec;91(12):2608-14.
    PMID: 20739117 DOI: 10.1016/j.jenvman.2010.07.042
    This study analyzes and compares the results of leachate composition at the semi-aerobic Pulau Burung Landfill Site (PBLS) (unaerated pond and intermittently aerated pond) and the anaerobic Kulim Sanitary Landfill in the northern region of Malaysia. The raw samples were collected and analyzed for twenty parameters. The average values of the parameters such as phenols (1.2, 6.7, and 2.6 mg/L), total nitrogen (448, 1200, and 300 mg/L N-TN), ammonia-N (542, 1568, and 538 mg/L NH(3)-N), nitrite (91, 49, and 52 mg/L NO(2)(-)-N), total phosphorus (21, 17, and 19 mg/L), BOD(5) (83, 243, and 326 mg/L), COD (935, 2345, and 1892 mg/L), BOD(5)/COD (0.096,0.1124,0.205%), pH (8.20, 8.28, and 7.76), turbidity (1546, 180, and 1936 Formazin attenuation units (FAU)), and color (3334, 3347, and 4041 Pt Co) for leachate at the semi-aerobic PBLS (unaerated and intermittently aerated) and the anaerobic Kulim Sanitary Landfill were recorded, respectively. The obtained results were compared with previously published data and data from the Malaysia Environmental Quality Act 1974. The results indicated that Pulau Burung leachate was more stabilized compared with Kulim leachate. Furthermore, the aeration process in PBLS has a considerable effect on reducing the concentration of several pollutants. The studied leachate requires treatment to minimize the pollutants to an acceptable level prior to discharge into water courses.
    Matched MeSH terms: Anaerobiosis
  11. Nor Faekah I, Fatihah S, Mohamed ZS
    Heliyon, 2020 Mar;6(3):e03594.
    PMID: 32258460 DOI: 10.1016/j.heliyon.2020.e03594
    A bench-scale model of a partially packed upflow anaerobic fixed film (UAF) reactor was set up and operated at five different hydraulic retention times (HRTs) of (17, 14, 10, 8, and 5) days. The reactor was fed with synthetic rubber wastewater consisting of a chemical oxygen demand (COD) concentration of 6355-6735 mg/L. The results were analyzed using the Monod model, the Modified Stover-Kincannon models, and the Grau Second-Order Model. The Grau Second-Order model was found to best fit the experimental data. The biokinetic constant values, namely the growth yield coefficient (Y) and the endogenous coefficient (Kd) were 0.027 g VSS/g COD and 0.1705 d-1, respectively. The half-saturation constant (Ks) and maximum substrate utilization rate (K) returned values of 84.1 mg/L and 0.371 d-1, respectively, whereas the maximum specific growth rate of the microorganism (μmax) was 0.011 d-1. The constants, Umax and KB, of the Stover-Kincannon model produced values of 6.57 g/L/d and 6.31 g/L/d, respectively. Meanwhile, the average second-order substrate removal rate, ks(2), was 105 d-1. These models gave high correlation coefficients with the value of R2 = 80-99% and these indicated that these models can be used in designing UAF reactor consequently predicting the behaviour of the reactor.
    Matched MeSH terms: Anaerobiosis
  12. Wong MV, Ho YW, Tan SG, Abdullah N, Jalaludin S
    FEMS Microbiol Lett, 1995 Dec 01;134(1):9-14.
    PMID: 8593960
    Isolates of anaerobic fungi obtained from the rumen, duodenum and faeces of sheep were identified as Piromyces mae based on their morphological characteristics observed using light microscopy. There was no significant morphological variation among the isolates of P. mae from the rumen, duodenum and faeces. Isozymes of 12 isolates of P. mae (one each from the rumen, duodenum and faeces from 4 different sheep) were analysed by PAGE. A total of 12 isozymes were studied and 5 isozyme loci were successfully typed. They were malic enzyme, malate dehydrogenase, shikimate dehydrogenase, alpha-esterase and beta-esterase. All the isolates of P. mae regardless of whether they were from the rumen, duodenum or faeces or from different animals produced very similar isozyme banding patterns for each of the enzyme systems. The similar isozyme profiles of the isolates indicate that they are of the same species although they exist in different regions of the alimentary tract.
    Matched MeSH terms: Anaerobiosis
  13. Ho YW, Khoo IY, Tan SG, Abdullah N, Jalaludin S, Kudo H
    Microbiology (Reading), 1994 Jun;140 ( Pt 6):1495-504.
    PMID: 8081508
    Isozymes of 23 cultures of the anaerobic rumen fungi and seven cultures of aerobic chytridiomycete fungi were analysed by PAGE. A total of 14 isozyme loci were successfully typed by PAGE. They were peptidase A & C-1, peptidase A & C-2, peptidase D-1, peptidase D-2, malate dehydrogenase-1, malate dehydrogenase-2, esterase-1, esterase-2, malic enzyme-1, malic enzyme-2, isocitrate dehydrogenase, shikimate dehydrogenase, phosphoglucomutase and 6-phosphogluconate dehydrogenase. Isozyme analysis can be used for studying the genetic relationships among the different anaerobic rumen fungi and the aerobic chytridiomycete fungi and the isozyme characteristics can serve as additional taxonomic criteria in the classification of the anaerobic rumen fungi. A dendrogram based on the isozyme data demonstrated that the anaerobic rumen fungi formed a cluster, indicating a monophyletic group, distinctly separated from the aerobic chytridiomycete fungi. Piromyces communis and P. minutus showed a close relationship but P. spiralis showed a more distant relationship to both P. communis and P. minutus. Piromyces as a whole was more related to Caecomyces than to Neocallimastix. Orpinomyces was also found to be more related to Piromyces and Caecomyces than to Neocallimastix. Orpinomyces intercalaris C 70 from cattle showed large genetic variation from O. joyonii, indicating that it is a different species.
    Matched MeSH terms: Anaerobiosis
  14. Kar Soon T, Al-Azad S, Ransangan J
    J Microbiol Biotechnol, 2014 Aug;24(8):1034-43.
    PMID: 24759424
    This study determined the effect of light intensity and photoperiod on the dry cell weight and total amount of carotenoids in four isolates of purple non-sulfur bacteria obtained from shaded and exposed microhabitats of a mangrove ecosystem in Kota Kinabalu, Sabah, Malaysia. The initial isolation of the bacteria was carried out using synthetic 112 medium under anaerobic conditions (2.5 klx) at 30 ± 2°C. On the basis of colony appearance, cell morphology, gram staining, motility test, and 16S rRNA gene sequencing analyses, all four bacteria were identified as Afifella marina. One of the bacterial isolates, designated as Af. marina strain ME, which was extracted from an exposed mud habitat within the mangrove ecosystem, showed the highest yield in dry cell weight (4.32± 0.03 g/l) as well as total carotenoids (0.783 ± 0.002 mg/g dry cell weight). These values were significantly higher than those for dry cell weight (3.77 ± 0.02g/l ) and total carotenoid content (0.706 ± 0.008 mg/g) produced by the isolates from shaded habitats. Further analysis of the effect of 10 levels of light intensity on the growth characteristics of Af. marina strain ME showed that the optimum production of dry cell weight and total carotenoids was achieved at different light intensities and incubation periods. The bacterium produced the highest dry cell weight of 4.98 g/l at 3 klx in 72 h incubation, but the carotenoid production of 0.783 mg/g was achieved at 2.5 klx in 48 h incubation. Subsequent analysis of the effect of photoperiod on the production of dry cell weight and total carotenoids at optimum light intensities (3 and 2.5 klx, respectively) revealed that 18 and 24 h were the optimum photoperiods for the production of dry cell weight and total carotenoids, respectively. The unique growth characteristics of the Af. marina strain ME can be exploited for biotechnology applications.
    Matched MeSH terms: Anaerobiosis
  15. Ghani B, Takai M, Hisham NZ, Kishimoto N, Ismail AK, Tano T, et al.
    Appl Environ Microbiol, 1993 Apr;59(4):1176-80.
    PMID: 16348915
    A Mo -reducing bacterium (strain 48), which grew on medium supplemented with 200 mM Mo, was isolated from stream water obtained from Chengkau, Malaysia. The chemical properties of strain 48 conform to the characteristics of Enterobacter cloacae. Under anaerobic conditions in the glucose-yeast extract medium containing phosphate ion (2.9 mM) and Mo (10 mM), the bacterium reduced Mo to form molybdenum blue. Approximately 27% of Mo added to the medium was reduced after 28 h of cultivation. The reduction of Mo with glucose as an electron donor was strongly inhibited by iodoacetic acid, sodium fluoride, and sodium cyanide, suggesting an involvement of the glycolytic pathway and electron transport in Mo reduction. NADH and N,N,N',N' -tetramethyl-p-phenylenediamine served as electron donors for Mo reduction. When NADH was used as an electron donor, at first cytochrome b in the cell extract was reduced, and then molybdenum blue was formed. Sodium cyanide strongly inhibited Mo reduction by NADH (5 mM) but not the reduction of cytochrome b in the cell extract, suggesting that the reduced component of the electron transport system after cytochrome b serves as an electron donor for Mo reduction. Both ferric and stannous ions strongly enhanced the activity of Mo reduction by NADH.
    Matched MeSH terms: Anaerobiosis
  16. Ng CA, Wong LY, Chai HY, Bashir MJK, Ho CD, Nisar H, et al.
    Water Sci Technol, 2017 Sep;76(5-6):1389-1398.
    PMID: 28953465 DOI: 10.2166/wst.2017.326
    Three different sizes of powdered activated carbon (PAC) were added in hybrid anaerobic membrane bioreactors (AnMBRs) and their performance was compared with a conventional AnMBR without PAC in treating palm oil mill effluent. Their working volume was 1 L each. From the result, AnMBRs with PAC performed better than the AnMBR without PAC. It was also found that adding a relatively smaller size of PAC (approximately 100 μm) enhanced the chemical oxygen demand removal efficiency to 78.53 ± 0.66%, while the concentration of mixed liquor suspended solid and mixed liquor volatile suspended solid were 8,050 and 6,850 mg/L, respectively. The smaller size of PAC could also enhance the biofloc formation and biogas production. In addition, the smaller particle sizes of PAC incorporated into polyethersulfone membrane resulted in higher performance of membrane fouling control and produced better quality of effluent as compared to the membrane without the addition of PAC.
    Matched MeSH terms: Anaerobiosis
  17. Ngatiman M, Jami MS, Abu Bakar MR, Subramaniam V, Loh SK
    Heliyon, 2021 Jan;7(1):e05931.
    PMID: 33490684 DOI: 10.1016/j.heliyon.2021.e05931
    The formation of struvite crystals or magnesium ammonium phosphate (MgNH4PO4) in palm oil mill effluent (POME) occurs as early as in the secondary stage of POME treatment system. Its growth continues in the subsequent tertiary treatment which reduces piping diameter, thus affecting POME treatment efficiency. Hypothesis. The beneficial use of the crystal is the motivation. This occurrence is rarely reported in scientific articles despite being a common problem faced by palm oil millers. The aim of this study is to characterize struvite crystals found in an anaerobic digester of a POME treatment facility in terms of their physical and chemical aspects. The compositions, morphology and properties of these crystals were determined via energy dispersive spectroscopy (EDS), elemental analysis, scanning electron microscopy (SEM) and x-ray diffraction (XRD). Solubility tests were carried out to establish solubility curve for struvite from POME. Finally, crystal growth experiment was done applying reaction crystallization method to demonstrate struvite precipitation from POME. Results showed that high phosphorous (P) (24.85 wt%) and magnesium (Mg) (21.33 wt%) content was found in the struvite sample. Elemental analysis detected carbon (C), hydrogen (H), nitrogen (N) and sulfur (S) below 4 wt%. The crystals analysed by XRD in this study were confirmed as struvite with 94.8% struvite mineral detected from its total volume. Having an orthorhombic crystal system, struvite crystals from POME recorded an average density of 1.701 g cm-3. Solubility curve of struvite from POME was established with maximum solubility of 275.6 mg L-1 at pH 3 and temperature 40 °C. Minimum solubility of 123.6 mg L-1 was recorded at pH 7 and temperature 25 °C. Crystal growth experiment utilizing POME as the source medium managed to achieve 67% reduction in phosphorous content. This study concluded that there is a potential of harnessing valuable nutrients from POME in the form of struvite. Struvite precipitation technology can be adapted in the management of POME in order to achieve maximum utilization of the nutrients that are still abundant in POME. At the same time maximization of nutrient extractions from POME will also reduce pollutants loading in the final discharge.
    Matched MeSH terms: Anaerobiosis
  18. Bee ST, Nithiyaa M, Sin LT, Tee TT, Rahmat AR
    Pak J Biol Sci, 2013 Oct 15;16(20):1104-12.
    PMID: 24506009
    This study was aimed to investigate the production of methane gas from three different types of food waste (vegetables waste, fruit waste and grain waste) using batch type anaerobic digestion method. The digestion process was conducted by using temperature range of 27 to 36 degrees C and pH 6.5 to 7.5 to yield an optimum condition for the digestion process. The digestion was continued for a period of two weeks with the aid of cow dung as the inoculums. It was found that the grain waste yielded the highest methane 2546 mL due to the high content of carbohydrate. At the mean time, the fruit waste produced the second highest methane gas with 2000 mL as well as the vegetable waste generated the lowest methane gas with volume of 1468 mL. The vegetable waste produced the lowest methane gas because the vegetables waste contains high fibres and cellulose walls but low in glucose amount. For the fertilization test, fruit waste demonstrated the best observation for the growth of plant due to high content of potassium and followed by vegetable waste. The least effective fertilizer was grain waste due to less content of nutrients essential for plants growth.
    Matched MeSH terms: Anaerobiosis
  19. Hosen, Md Sabuj, Mariatul Fadzillah Mansor, Ainoor Mariana Mohd Ali, Alam, Md. Zahangir
    MyJurnal
    Increasing population, urbanization and industrial activities have increased the amount of solid waste worldwide. Food waste (FW) and sewage sludge (SS) are some of the solid wastes. Co-digesting of both substrates may improve process stabilization to increase biogas production and overcome the nutrients imbalance. Thus, anaerobic co-digestion has been recognized as a technology that could provide a clean renewable energy source and help reducing the landfill problem. In this study, the interaction between FW and SS as co-substrates in anaerobic digestion was studied under mesophilic temperature 36C (± 0.5). The experiments were conducted using five batch reactors with different ratios of substrates. There are four different analyses used to identify the characteristics of FW and SS, which are pH, reducing sugar (RS), total solid (TS), and total carbohydrate (TC). Water displacement method was used to record biogas yield. The experimental results showed that the highest biogas yield was from the composition of 50:50 (FW: SS) with a biogas volume of 1150.14 mL, while the least was the composition of 0:100 (FW: SS) with 170.47 mL biogas produced. The results for substrate degradation showed that the composition of 100:0 (FW: SS) has the highest percentage degradation for reducing sugar with the percentage of 56%, while the minimum was 0:100 (FW: SS) with a percentage of 35%. Besides, for TC, the highest percentage of degradation was the composition 50:50 (FW: SS) with 84%, and the least was 0:100 (FW: SS) with 44%. This study proves that using FW and SS enhanced biogas production as well as reducing the current issues of waste disposal.
    Matched MeSH terms: Anaerobiosis
  20. Latif MA, Ghufran R, Wahid ZA, Ahmad A
    Water Res, 2011 Oct 15;45(16):4683-99.
    PMID: 21764417 DOI: 10.1016/j.watres.2011.05.049
    The UASB process among other treatment methods has been recognized as a core method of an advanced technology for environmental protection. This paper highlights the treatment of seven types of wastewaters i.e. palm oil mill effluent (POME), distillery wastewater, slaughterhouse wastewater, piggery wastewater, dairy wastewater, fishery wastewater and municipal wastewater (black and gray) by UASB process. The purpose of this study is to explore the pollution load of these wastewaters and their treatment potential use in upflow anaerobic sludge blanket process. The general characterization of wastewater, treatment in UASB reactor with operational parameters and reactor performance in terms of COD removal and biogas production are thoroughly discussed in the paper. The concrete data illustrates the reactor configuration, thus giving maximum awareness about upflow anaerobic sludge blanket reactor for further research. The future aspects for research needs are also outlined.
    Matched MeSH terms: Anaerobiosis*
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links