Displaying publications 561 - 580 of 1099 in total

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  1. Mapping the cumulative impacts of long-term mining disturbance and progressive rehabilitation on ecosystem services
    Wang Z, Lechner AM, Yang Y, Baumgartl T, Wu J
    Sci Total Environ, 2020 May 15;717:137214.
    PMID: 32062237 DOI: 10.1016/j.scitotenv.2020.137214
    Open-cut coal mining can seriously disturb and reshape natural landscapes which results in a range of impacts on local ecosystems and the services they provide. To address the negative impacts of disturbance, progressive rehabilitation is commonly advocated. However, there is little research focusing on how these impacts affect ecosystem services within mine sites and changes over time. The aim of this study was to assess the cumulative impacts of mining disturbance and rehabilitation on ecosystem services through mapping and quantifying changes at multiple spatial and temporal scales. Four ecosystem services including carbon sequestration, air quality regulation, soil conservation and water yield were assessed in 1989, 1997, 2005 and 2013. Disturbance and rehabilitation was mapped using LandTrendr algorithm with Landsat. We mapped spatial patterns and pixel values for each ecosystem service with corresponding model and the landscape changes were analyzed with landscape metrics. In addition, we assessed synergies and trade-offs using Spearman's correlation coefficient for different landscape classes and scales. The results showed that carbon sequestration, air quality regulation and water yield services were both positively and negatively affected by vegetation cover changes due to mined land disturbance and rehabilitation, while soil conservation service were mainly influenced by topographic changes. There were strong interactions between carbon sequestration, air quality regulation and water yield, which were steady among different spatial scales and landscape types. Soil conservation correlations were weak and changed substantially due to differences of spatial scales and landscape types. Although there are limitations associated with data accessibility, this study provides a new research method for mapping impacts of mining on ecosystem services, which offer spatially explicit information for decision-makers and environmental regulators to carry out feasible policies, balancing mining development with ecosystem services provision.
    Matched MeSH terms: Soil
  2. Fulltext Complete genome sequence of Sphingomonas paucimobilis AIMST S2, a xenobiotic-degrading bacterium
    Ravintheran SK, Sivaprakasam S, Loke S, Lee SY, Manickam R, Yahya A, et al.
    Sci Data, 2019 11 25;6(1):280.
    PMID: 31767854 DOI: 10.1038/s41597-019-0289-x
    Complete genomes of xenobiotic-degrading microorganisms provide valuable resources for researchers to understand molecular mechanisms involved in bioremediation. Despite the well-known ability of Sphingomonas paucimobilis to degrade persistent xenobiotic compounds, a complete genome sequencing is lacking for this organism. In line with this, we report the first complete genome sequence of Sphingomonas paucimobilis (strain AIMST S2), an organophosphate and hydrocarbon-degrading bacterium isolated from oil-polluted soil at Kedah, Malaysia. The genome was derived from a hybrid assembly of short and long reads generated by Illumina HiSeq and MinION, respectively. The assembly resulted in a single contig of 4,005,505 bases which consisted of 3,612 CDS and 56 tRNAs. An array of genes involved in xenobiotic degradation and plant-growth promoters were identified, suggesting its' potential role as an effective microorganism in bioremediation and agriculture. Having reported the first complete genome of the species, this study will serve as a stepping stone for comparative genome analysis of Sphingomonas strains and other xenobiotic-degrading microorganisms as well as gene expression studies in organophosphate biodegradation.
    Matched MeSH terms: Soil Microbiology
  3. Fulltext Bioavailability of zinc oxide nano particle with fly ash soil for the remediation of metals by Parthenium hysterophorus
    Ahmad A, Ghufran R, Al-Hosni TK
    J Environ Health Sci Eng, 2019 Dec;17(2):1195-1203.
    PMID: 32030185 DOI: 10.1007/s40201-019-00434-2
    To investigate the interaction of zinc oxide nanoparticles (ZnO NPs) with fly ash soil (FAS) for the reduction of metals from FAS by Parthenium hysterophorus were studied. The average accumulation of metals by P. hysterophorus stem were Fe 79.6%; Zn 88.5%; Cu 67.5%; Pb 93.6%; Ni 43.5% and Hg 39.4% at 5.5 g ZnO NP. The concentration of ZnO NP at 1.5 g did not affect the metals accumulation, however at 5.5 g ZnO NP showed highest metal reduction was 96.7% and at 10.5-15.5 g ZnO NP of 19.8%. The metal reduction rate was R
    max
    for Fe 16.4; Zn 21.1; Pb 41.9; Hg 19.1 was higher than Ni 6.4 and Cu 11.3 from the FAS at 5.5 g ZnO NP whereas, the reduction rate of Pb showed highest. With doses of 5.5 g ZnO NP the biomass increased upto 78%; the metal reduced upto 98.7% with the share of 100% ZnO NP from FAS. Further investigation with phytotoxicity the plant reactive oxygen species (ROS) production were affected due was mainly due to the recovery of metals from FAS (R2 = 0.99).
    Matched MeSH terms: Soil
  4. Fulltext An assessment of oil palm plantation aboveground biomass stocks on tropical peat using destructive and non-destructive methods
    Lewis K, Rumpang E, Kho LK, McCalmont J, Teh YA, Gallego-Sala A, et al.
    Sci Rep, 2020 02 10;10(1):2230.
    PMID: 32041975 DOI: 10.1038/s41598-020-58982-9
    The recent expansion of oil palm (OP, Elaeis guineensis) plantations into tropical forest peatlands has resulted in ecosystem carbon emissions. However, estimates of net carbon flux from biomass changes require accurate estimates of the above ground biomass (AGB) accumulation rate of OP on peat. We quantify the AGB stocks of an OP plantation on drained peat in Malaysia from 3 to 12 years after planting using destructive harvests supported by non-destructive surveys of a further 902 palms. Peat specific allometric equations for palm (R2 = 0.92) and frond biomass are developed and contrasted to existing allometries for OP on mineral soils. Allometries are used to upscale AGB estimates to the plantation block-level. Aboveground biomass stocks on peat accumulated at ~6.39 ± 1.12 Mg ha-1 per year in the first 12 years after planting, increasing to ~7.99 ± 0.95 Mg ha-1 yr-1 when a 'perfect' plantation was modelled. High inter-palm and inter-block AGB variability was observed in mature classes as a result of variations in palm leaning and mortality. Validation of the allometries defined and expansion of non-destructive inventories across alternative plantations and age classes on peat would further strengthen our understanding of peat OP AGB accumulation rates.
    Matched MeSH terms: Soil
  5. A new species of Podolestes Selys, 1862 from peat swamp forest in Sarawak (Odonata: Zygoptera: Argiolestidae)
    Dow RA, Ngiam RWJ
    Zootaxa, 2019 Apr 18;4586(3):zootaxa.4586.3.7.
    PMID: 31716120 DOI: 10.11646/zootaxa.4586.3.7
    Podolestes parvus sp. nov. is described and illustrated from both sexes from Sarawak, Malaysian Borneo (holotype male Maludam National Park, Betong Division, Sarawak, 10 vii 2012, deposited in RMNH). The new species is closest to P. atomarius Lieftinck, 1950 and is the smallest species yet known in its genus. A full set illustrations of P. atomarius is provided for comparison. [Species Zoobank URL: urn:lsid:zoobank.org:act:EE7ABAB0-8683-4D25-8A2C-76977931FD87].
    Matched MeSH terms: Soil
  6. Bacterial community diversity in the rhizosphere of nickel hyperaccumulator plant species from Borneo Island (Malaysia)
    Lopez S, van der Ent A, Sumail S, Sugau JB, Buang MM, Amin Z, et al.
    Environ Microbiol, 2020 04;22(4):1649-1665.
    PMID: 32128926 DOI: 10.1111/1462-2920.14970
    The Island of Borneo is a major biodiversity hotspot, and in the Malaysian state of Sabah, ultramafic soils are extensive and home to more than 31 endemic nickel hyperaccumulator plants. The aim of this study was to characterize the structure and the diversity of the rhizosphere bacterial communities of several of these nickel hyperaccumulator plants and factors that affect these bacterial communities in Sabah. The most abundant phyla were Proteobacteria, Acidobacteria and Actinobacteria. At family level, Burkholderiaceae and Xanthobacteraceae (Proteobacteria phylum) were the most abundant families in the hyperaccumulator rhizospheres. Redundancy analysis based on soil chemical analyses and relative abundances of the major bacterial phyla showed that abiotic factors of the studied sites drove the bacterial diversity. For all R. aff. bengalensis rhizosphere soil samples, irrespective of studied site, the bacterial diversity was similar. Moreover, the Saprospiraceae family showed a high representativeness in the R. aff. bengalensis rhizosphere soils and was linked with the nickel availability in soils. The ability of R. aff. bengalensis to concentrate nickel in its rhizosphere appears to be the major factor driving the rhizobacterial community diversity unlike for other hyperaccumulator species.
    Matched MeSH terms: Soil
  7. Radioactivity and heat production characterization by natural gamma ray well logging and multi-fractal techniques in banting district, Malaysia
    Asfahani J, Samuding K, Mostapa R, Othman O
    Appl Radiat Isot, 2021 Jan;167:109296.
    PMID: 33022484 DOI: 10.1016/j.apradiso.2020.109296
    Natural gamma ray well logging technique is used to characterize the radioactivity (GR) laterally and vertically in Banting district, SW of Malaysia. Seven drilled boreholes, along N-S profile with their natural gamma ray records are utilized to compute the heat production (HP) parameter, based on the Bucker and Rybach relationship.The analysis of 3467 measured points in those boreholes indicates that GR varies between 6.24 API and 358.4 API with an average of 79.95 API, while HP varies between 0.086 and 5.65 μw/m3 with an average of 1.25 μw/m3.The multi-fractal Concentration-Number (C-N) is used to characterize the radioactivity and heat production variations and to isolate different GR and HP populations in the study region. The high radioactivity and heat production ranges are mainly related to the silty clay layers, accompanied by uranium and thorium.
    Matched MeSH terms: Soil Pollutants, Radioactive
  8. Isolation and functional characterization of 5-enolpyruvylshikimate 3-phosphate synthase gene from glyphosate-tolerant Pseudomonas nitroreducens strains FY43 and FY47
    Tan XL, Othman RY, Teo CH
    3 Biotech, 2020 Apr;10(4):183.
    PMID: 32257739 DOI: 10.1007/s13205-020-02176-7
    5-Enolpyruvylshikimate 3-phosphate synthase (EPSPS) is the primary target for the broad-spectrum herbicide, glyphosate. Improvement of EPSPS gene for high level of glyphosate tolerance is important to generate glyphosate-tolerant crops. In this study, we report the isolation and characterization of EPSPS genes of glyphosate-tolerant Pseudomonas nitroreducens strains FY43 and FY47. Both P. nitroreducens strains FY43 and FY47, which showed glyphosate tolerance up to 8.768% (518.4 mM, 32 × higher than field application), were isolated from soil samples collected from oil palm plantation with a long history of glyphosate application. The glyphosate tolerance property of EPSPS genes of strains FY43 and FY47 was functionally characterized by expressing the genes in Escherichia coli strain BL21(DE3). Error-prone PCR was performed to mutagenize native EPSPS gene of strains FY43 and FY47. Ten mutagenized EPSPS with amino acid changes (R21C, N265S, A329T, P71L, T258A, L184F, G292C, G292S, L35F and A242V) were generated through error-prone PCR. Both native and mutated EPSPS genes of strains FY43 and FY47 were introduced into Escherichia coli strain BL21(DE3) and transformants were selected on basal salt medium supplemented with 8.768% (518.4 mM) glyphosate. Mutants with mutations (R21C, N265S, A329T, P71L, T258A, L35F, A242V, L184F and G292C) showed sensitivity to 8.768% glyphosate, whereas glyphosate tolerance for mutant with G292S mutation was not affected by the mutation.
    Matched MeSH terms: Soil
  9. Is flooding considered a threat in the degraded tropical peatlands?
    Lupascu M, Varkkey H, Tortajada C
    Sci Total Environ, 2020 Jun 25;723:137988.
    PMID: 32392686 DOI: 10.1016/j.scitotenv.2020.137988
    Tropical peatland degradation due to oil palm plantation development has reduced peat's ability to naturally regulate floods. In turn, more severe and frequent flooding on peatlands could seriously impair plantation productivity. Understanding the roles of peatland ecosystems in regulating floods has become essential given the continued pressure on land resources, especially in Southeast Asia. However, the limited knowledge on this topic has resulted in the oversimplifications of the relationships between floods, commercial plantations and peatland sustainability, creating major disagreement among policymakers at different levels in governments, companies, NGOs and society. Hence, this study identifies whether flood policies are integrated within peatland management through a qualitative policy analysis of publicly available papers, government reports, and other official documents that discuss flooding, and/or more in general, hydrology in peatlands. Document analysis was then triangulated with data obtained from several semi-structured discussions. The analysis indicates that the industry on peatlands and the peatland's environmental sustainability could be threatened by increased flooding. We show that, in spite of this, flood policies in SE Asian countries like Malaysia and Indonesia have not been well-integrated into peatland management. We also discuss how the countries could move forward to overcome this problem.
    Matched MeSH terms: Soil
  10. Fulltext Somatic Embryogenesis and Plantlet Regeneration in the Carica papaya L. cv. Eksotika
    Al-Shara B, Taha RM, Mohamad J, Elias H, Khan A
    Plants (Basel), 2020 Mar 12;9(3).
    PMID: 32178429 DOI: 10.3390/plants9030360
    A highly efficient protocol for regeneration of Carica papaya L. cv. Eksotika somatic embryos from immature zygotic embryos was developed. This study was designed to overcome the obstacles in regeneration of somatic embryos from immature zygotic embryos of "Eksotika", especially problems associated with formation of better root quality and callus formation at the base of somatic embryos. Somatic embryos were generated by incubation of immature zygotic embryos in half-strength salt Murashige and Skoog (MS) medium with full-strength vitamins supplemented with 7.5 mg L-1 2,4-D, 100 mg L-1 L-glutamine, 50 mg L-1myo-inositol, 45 mg L-1 adenine sulphate, 0.33% gelrite, and 6% sucrose, followed by transfer to maturation medium consisting of ½ MS medium supplemented with 5 mg L-1 phloroglucinol, 100 mg L-1 L-glutamine, 100 mg L-1myo-inositol, 68 mg L-1 adenine sulphate, 0.38% gelrite, and 3% sucrose. After that, well-formed somatic embryos were transferred to MS medium containing 3% sucrose and 0.8% agar for shoot production. The embryos were elongated in MS medium supplemented with 1 mg L-1 gibberellic acid, 0.5 mg L-1 indole-3-butyric acid, 100 mg L-1myo-inositol, and 3.76 mg L-1 riboflavin. Root regeneration was achieved on MS medium containing 7.9 mg L-1 phloroglucinol and supported with vermiculite after 4 days of cultivation on ½ MS medium with 2 mg L-1 indole-3-butyric acid. After the rooting phase, in vitro plantlets were acclimatized in peat moss soil.
    Matched MeSH terms: Soil
  11. Biocontrol efficacy of Trichoderma asperellum-enriched coconut fibre against Fusarium wilts of cherry tomato
    Hasan ZAE, Mohd Zainudin NAI, Aris A, Ibrahim MH, Yusof MT
    J Appl Microbiol, 2020 Oct;129(4):991-1003.
    PMID: 32324939 DOI: 10.1111/jam.14674
    AIMS: Agro-based wastes were evaluated as a medium for mass micropropagule production and optimal efficacy of Trichoderma asperellum B1092 in controlling Fusarium oxysporum f. sp. lycopersici and promoting tomato growth. This study focused on biological control because pathogen persistence in the soil makes the disease difficult to control.

    METHODS AND RESULTS: Rice bran, biochar, empty fruit bunches, coconut fibres, compost, top soil and mixed soil were evaluated as media for mass multiplication of T. asperellum, which is effective in controlling plant pathogens. Yielding the most colony forming units (CFU) among the media, coconut fibre was deemed most suitable for promoting sporulation. After 120 days on the medium, T. asperellum B1902 produced 9·053 × 105  CFU per gram coconut fibre; oil palm empty fruit bunches was second highest (7·406 × 105  CFU per gram). In field tests of T. asperellum B1092 against F. oxysporum f. sp lycopersici (causing Fusarium wilt of cherry tomato), B1092 significantly promoted plant growth compared to the control. The efficacy of this formulation resulted in increased growth of roots and shoots tomato plants and total lycopene, sugar, K, N, Ca, P and Mg content after 120 days.

    CONCLUSIONS: Trichoderma asperellum B1092 showed great field potential for improving productivity and quality of tomatoes and in controlling Fusarium wilt of cherry tomato.

    SIGNIFICANCE AND IMPACT OF THE STUDY: This innovative approach using a cheap agro-waste to control the persistent soil-borne Fusarium pathogen of cherry tomato should increase soil survival rate of Trichoderma and has potential for upscaling in the field for other crops.

    Matched MeSH terms: Soil
  12. Examining CO2 and N2O pollution and reduction from forestry application of pure and mixture forest
    Kong Y, Ma NL, Yang X, Lai Y, Feng Z, Shao X, et al.
    Environ Pollut, 2020 Oct;265(Pt A):114951.
    PMID: 32554093 DOI: 10.1016/j.envpol.2020.114951
    Greenhouse gases (GHGs) carbon dioxide (CO2) and nitrous oxide (N2O), contribute significantly to global warming, and they have increased substantially over the years. Reforestation is considered as an important forestry application for carbon sequestration and GHGs emission reduction, however, it remains unknown whether reforestation may instead produce too much CO2 and N2O contibuting to GHGs pollution. This study was performed to characterize and examine the CO2 and N2O emissions and their controlling factors in different species and types of pure and mixture forest used for reforestation. Five soil layers from pure forest Platycladus orientalis (PO), Robinia pseudoacacia (RP), and their mixed forest P-R in the Taihang mountains of central China were sampled and incubated aerobically for 11 days. The P-R soil showed lower CO2 and N2O production potentials than those of the PO soils (P soil depths, cumulative CO2 production in PO and RP soils decreased, whereas CO2 and N2O production in P-R soil did not show similar pattern. Soil particle size fraction was the main factor influencing GHGs emissions, and the clay fraction showed negative correlation with cumulative CO2 and N2O production. In summary, compared with PO pure artificial forests, the mixture plantation mode can not only reduce GHGs pollution but also improve soil fertility, which is conducive to sustainable management of artificial forests.
    Matched MeSH terms: Soil
  13. Fulltext Efficacy of Albendazole-Pyrantel Pamoate Compared to Albendazole Alone for Trichuris trichiura Infection in Children: A Double Blind Randomised Controlled Trial
    Sapulete EJJ, de Dwi Lingga Utama IMG, Sanjaya Putra IGN, Kanya Wati D, Arimbawa IM, Gustawan IW
    Malays J Med Sci, 2020 May;27(3):67-74.
    PMID: 32684807 DOI: 10.21315/mjms2020.27.3.7
    Background: Soil transmitted helminths (STH) are intestinal nematodes and constitute one of the most neglected tropical diseases to exist. Objective: This study determined the efficacy of albendazole-pyrantel pamoate compared to albendazole in 8-12 years old children with Trichuris trichiura infection.

    Methods: A randomised controlled trial was conducted between October 2017 and February 2018 on participants whose stool examinations confirmed the presence of Trichuris trichiura infection. The subjects were randomised into two groups. The statistical analysis used Chi-square test.

    Results: There were 392 of 600 children at five public elementary schools in Bangli and Bali and were infected with Trichuris trichiura. The cure rate of Trichuris trichiura infection seven days following treatment was lower with the combination of albendazole and pyrantel pamoate compared to that of albendazole. The egg reduction rate of Trichuris trichiura infection was lower with the combination of albendazole and pyrantel pamoate compared to albendazole.

    Conclusion: The study indicated that a combination of albendazole and pyrantel pamoate does not improve cure rate or egg reduction rate in 8-12 years old children with Trichuris trichiura infection.

    Matched MeSH terms: Soil
  14. Fulltext Root architecture, rooting profiles and physiological responses of potential slope plants grown on acidic soil
    Dorairaj D, Suradi MF, Mansor NS, Osman N
    PeerJ, 2020;8:e9595.
    PMID: 32904129 DOI: 10.7717/peerj.9595
    Globally, there has been an increase in the frequency of landslides which is the result of slope failures. The combination of high intensity rainfall and high temperature resulted in the formation of acidic soil which is detrimental to the healthy growth of plants. Proper plant coverage on slopes is a prerequisite to mitigate and rehabilitate the soil. However, not all plant species are able to grow in marginal land. Thus, this study was undertaken to find a suitable slope plant species. We aimed to evaluate the effect of different soil pH on root profiles and growth of three different potential slope plant species namely, Melastoma malabathricum, Hibiscus rosa-sinensis and Syzygium campanulatum. M. malabathricum showed the highest tolerance to acidic soil as it recorded the highest plant height and photosynthetic rate. The root systems of M. malabathricum, H. rosa-sinensis and S. campanulatum were identified as M, VH- and R-types, respectively. The study proposed M. malabathricum which possessed dense and shallow roots to be planted at the toe or top of the slope while H. rosa-sinensis and S. campanulatum to be planted in the middle of a slope. S. campanulatum consistently recorded high root length and root length density across all three types of soil pH while M. malabathricum showed progressive increase in length as the soil pH increased. The root average diameter and root volume of M. malabathricum outperformed the other two plant species irrespective of soil pH. In terms of biomass, M. malabathricum exhibited the highest root and shoot dry weights followed by S. campanulatum. Thus, we propose M. malabathricum to be planted on slopes as a form of soil rehabilitation. The plant species displayed denser rooting, hence a stronger root anchorage that can hold the soil particles together which will be beneficial for slope stabilization.
    Matched MeSH terms: Soil
  15. Fulltext Aspergillus sydowii strain SCAU066 and aspergillus versicolor isolate BAB-6580: potential source of xylanolytic, cellulolytic and amylolytic enzymes
    Nur Syahira Mohammad, Zaidah Zainal Ariffin
    Science Letters, 2020;14(2):15-23.
    MyJurnal
    Fungi is known to produce a wide range of biologically active metabolites and enzymes. Enzymes produced by fungi are utilized in food and pharmaceutical industries because of their rich enzymatic profile. Filamentous fungi are particularly interesting due to their high production of extracellular enzymes which has a large industrial potential. The aim of this study is to isolate potential soil fungi species that are able to produce functional enzymes for industries. Five Aspergillus species were successfully isolated from antibiotic overexposed soil (GPS coordinate of N3.093219 E101.40269) by standard microbiological method. The isolated fungi were identified via morphological observations and molecular tools; polymerase chain reactions, ITS 1 (5’- TCC GTA GGT GAA CCT GCG G3’) forward primer and ITS 4 (5’-TCC TCC GCT TAT TGA TAT GC-3’) reverse primer. The isolated fungi were identified as Aspergillus sydowii strain SCAU066, Aspergillus tamarii isolate TN-7, Aspergillus candidus strain KUFA 0062, Aspergillus versicolor isolate BAB-6580, and Aspergillus protuberus strain KAS 6024. Supernatant obtained via submerged fermentation of the isolated fungi in potato dextrose broth (PDB) and extracted via centrifugation was loaded onto specific media to screen for the production of xylanolytic, cellulolytic and amylolytic enzymes. The present findings indicate that Aspergillus sydowii strain SCAU066 and Aspergillus versicolor isolate BAB-6580 have great potential as an alternative source of xylanolytic, cellulolytic and amylolytic enzymes.
    Matched MeSH terms: Soil
  16. Fulltext Chitosan Epoxidized Natural Rubber Biocomposites for Sorption and Biodegradability Studies
    Raju G, Mas Haris MRH, Azura AR, Ahmed Mohamed Eid AM
    ACS Omega, 2020 Nov 10;5(44):28760-28766.
    PMID: 33195929 DOI: 10.1021/acsomega.0c04081
    The slow-release mechanism of copper into soil followed by soil biodegradation was studied using the chitosan (CTS)/epoxidized natural rubber (ENR) biocomposite. The biocomposite was prepared by homogenizing CTS in ENR50 (ENR with about 50% epoxy content) latex in the presence of curing agents and acetic acid. It was found that the adsorption property of the biocomposite was very much influenced by chitosan loading, where 20phrCTS-t-ENR biocomposite can absorb 76.31% of Cu(II) ions. The desorption study indicates that the copper (II) ion can be released at a very slow and control phase as proven by the kinetic study using zero-order, first-order, Higuchi, and Korsmeyer Peppas equations. The slow-release studies comply with the Higuchi square-root equation, indicating that the release process is diffusion-controlled. Results of desorption and biodegradation process suggest that this biocomposite has the potential use of being a slow-release matrix in the field of agriculture.
    Matched MeSH terms: Soil
  17. Fulltext Recent Understanding of Soil Acidobacteria and Their Ecological Significance: A Critical Review
    Kalam S, Basu A, Ahmad I, Sayyed RZ, El-Enshasy HA, Dailin DJ, et al.
    Front Microbiol, 2020;11:580024.
    PMID: 33193209 DOI: 10.3389/fmicb.2020.580024
    Acidobacteria represents an underrepresented soil bacterial phylum whose members are pervasive and copiously distributed across nearly all ecosystems. Acidobacterial sequences are abundant in soils and represent a significant fraction of soil microbial community. Being recalcitrant and difficult-to-cultivate under laboratory conditions, holistic, polyphasic approaches are required to study these refractive bacteria extensively. Acidobacteria possesses an inventory of genes involved in diverse metabolic pathways, as evidenced by their pan-genomic profiles. Because of their preponderance and ubiquity in the soil, speculations have been made regarding their dynamic roles in vital ecological processes viz., regulation of biogeochemical cycles, decomposition of biopolymers, exopolysaccharide secretion, and plant growth promotion. These bacteria are expected to have genes that might help in survival and competitive colonization in the rhizosphere, leading to the establishment of beneficial relationships with plants. Exploration of these genetic attributes and more in-depth insights into the belowground mechanics and dynamics would lead to a better understanding of the functions and ecological significance of this enigmatic phylum in the soil-plant environment. This review is an effort to provide a recent update into the diversity of genes in Acidobacteria useful for characterization, understanding ecological roles, and future biotechnological perspectives.
    Matched MeSH terms: Soil
  18. Role of nanocatalyst in the treatment of organochlorine compounds - A review
    El-Sheikh MA, Hadibarata T, Yuniarto A, Sathishkumar P, Abdel-Salam EM, Alatar AA
    Chemosphere, 2020 Nov 04.
    PMID: 33220978 DOI: 10.1016/j.chemosphere.2020.128873
    Since a few centuries ago, organochlorine compounds (OCs) become one of the threatened contaminants in the world. Due to the lipophilic and hydrophobic properties, OCs always discover in fat or lipid layers through bioaccumulation and biomagnification. The OCs are able to retain in soil, sediment and water for long time as it is volatile, OCs will evaporate from soil and condense in water easily and frequently, which pollute the shelter of aquatic life and it affects the function of organs and damage system in human body. Photocatalysis that employs the usage of semiconductor nanophotocatalyst and solar energy can be the possible alternative for current conventional water remediation technologies. With the benefits of utilizing renewable energy, no production of harmful by-products and easy operation, degradation of organic pollutants in rural water bodies can be established. Besides, nanophotocatalyst that is synthesized with nanotechnology outnumbered conventional catalyst with larger surface area to volume ratio, thus higher photocatalytic activity is observed. In contrast, disadvantages particularly no residual effect in water distribution network, requirement of post-treatment and easily affected by various factors accompanied with photocatalysis method cannot be ignored. These various factors constrained the photocatalytic efficiency via nanocatalysts which causes the full capacity of solar photocatalysis has yet to be put into practice. Therefore, further modifications and research are still required in nanophotocatalysts' synthesis to overcome limitations such as large band gaps and photodecontamination.
    Matched MeSH terms: Soil
  19. Fulltext A novel method for the quantification of industrial and municipal waste materials for environmental hazard assessment
    Arifin MH, Kayode JS, Ismail MKI, Abdullah AM, Embrandiri A, Nazer NSM, et al.
    MethodsX, 2021;8:101182.
    PMID: 33365262 DOI: 10.1016/j.mex.2020.101182
    A novel methodological approach was developed to quantified the volume of industrial waste desposal (IWD) site, combined with municipal waste materials (MWM), through the integration of a non-invasive, fast, and less expenssive RES2-D Electrical Resistivity Technique (ERT), using Wenner-Schlumberger electrode array geophysical method with Oasis Montaj software. Underground water bearing structures, and the eco-system are being contaminated through seepage of the plumes emanating from the mixtures of the industrial waste materials (IWM), made of moist cemented soil with municipal solid wastes (MSW) dumped at the site. The distribution of the contiminant hazardous plumes emanating from the waste materials' mixtures within the subsurface structural lithological layers was clearly map and delineated within the near-surface structures, using the triplicate technique to collect samples of the soil with the waste mixtures, and the water analysis for the presence of dissolved ions. The deployed method helped to monitor the seepage of the contaminant leachate plumes to the groundwater aquifer units via the ground surface, through the subsurface stratum lithological layers, and hence, estimation of the waste materials' volume was possibly approximated to be 312,000 m3. In summary, the novel method adopted are as presented below:•The novel method is transferable, reproduce-able, and most importantly, it is unambiguous technique for the quantification of environmental, industrial and municipal waste materials.•It helps to map the distribution of the plumes emanating from the waste materials' mixtures within the subsurface structural lithological layers that was clearly delineated within the near-surface structures underlain the study site.•The procedure helped in the monitoring of leachate contaminants plumes seepages into the surface water bodies and the groundwater aquifer units, via the ground surface, through to the porous subsurface stratum lithological layers.
    Matched MeSH terms: Soil
  20. Overview of the distribution of Burkholderia pseudomallei Sequence Types and the Emergence of Sequence Type 1342 in Malaysia
    Teh CSJ, Yap PSX, Zulkefli NJ, Subramaniam P, Sit PS, Kong ZX, et al.
    Transbound Emerg Dis, 2021 Jan 27.
    PMID: 33506647 DOI: 10.1111/tbed.14005
    Burkholderia pseudomallei, a Gram-negative bacterial pathogen that causes melioidosis, is of public health importance in endemic areas including Malaysia. An investigation of the molecular epidemiology links of B. pseudomallei would contribute to better understanding of the clonal relationships, transmission dynamics and evolutionary change. Multi-locus sequence typing (MLST) of 45 clinical B. pseudomallei isolates collected from sporadic meliodosis cases in Malaysia was performed. In addition, a total of 449 B. pseudomallei Malaysian strains submitted to the MLST database from 1964 until 2019 were included in the temporal analysis to determine the endemic sequence types (STs), emergence and re-emergence of ST(s). In addition, strain-specific distribution was evaluated using BURST tool. Genotyping of 45 clinical strains were resolved into 12 STs and the majority were affiliated with ST46 (n=11) and ST1342 (n=7). Concomitantly, ST46 was the most prevalent ST in Malaysia which first reported in 1964. All the Malaysian B. pseudomallei strains were resolved into 76 different STs with 36 of them uniquely present only in Malaysia. ST1342 was most closely related to ST1034, in which both STs were unique to Malaysia and first isolated from soil samples in Pahang, a state in Malaysia. The present study revealed a high diversity of B. pseudomallei in Malaysia. Localised evolution giving rise to the emergence of new STs was observed, suggesting that host and environmental factors play a crucial role in the evolutionary changes of B. pseudomallei.
    Matched MeSH terms: Soil
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