Displaying publications 1 - 20 of 27 in total

Abstract:
Sort:
  1. Comprehensive studies on optimization of ligno-hemicellulolytic enzymes by indigenous white rot hymenomycetes under solid-state cultivation using agro-industrial wastes
    Naidu Y, Siddiqui Y, Idris AS
    J Environ Manage, 2020 Apr 01;259:110056.
    PMID: 31929034 DOI: 10.1016/j.jenvman.2019.110056
    The disposal of oil palm biomass is a huge challenge in Malaysian oil palm plantations. The aim of this study was to develop efficient solid-state cultivated (SSC) ligno-hemicellulolytic bio-degrader formulations of indigenous white-rot hymenomycetes (Trametes lactinea FBW and Pycnoporus sanguineus FBR) utilizing oil palm empty fruit bunches (EFB), rubber wood sawdust (SD) and vermiculite (V) either alone or in combination as substrates. Based on significant laccase (849.40 U mg-1 protein), xylanase (42.26 U g-1 protein) and amylase (157.49 U g-1 protein) production, SD+V (T5) and V (T3) were the optimum substrates for SSC of T. lactinea FBW. Whereas, utilizing EFB (T1) substrate for SSC of P. sanguineus FBR enhanced the production of MnP (42.51 U mg-1 protein), LiP (103.20 U mg-1 protein) and CMCase (34.39 U g-1 protein), enzymes. Apparently, this is the first study reporting on the protein profiles by T. lactinea FBW, producing two isoforms of un-purified laccase (~55 and 70 kDa) and MnP (~40 and 60 kDa) and a CMCase band (~60 kDa) during SSC on SD+V (T5) substrate. Interestingly, this is also the first report to document a single isoform of un-purified laccase (~50 kDa), MnP (~45 kDa), CMCase (~60 kDa) and xylanase (~55 kDa) by P. sanguineus FBR during SSC on empty fruit bunches substrate. The computed Principal Component Analysis (PCA) Biplot analysis elucidated the relationship between the solid substrate compositions, the hymenomycete strain, ligno-hemicellulolytic enzyme profiles, and cultivation time. Therefore, it is suggested to use PCA as a tool for multivariate analysis method for comprehensive selection and optimization of ligno-hemicellulolytic enzyme cocktails by the indigenous white rot hymenomycetes. These non-toxic (acute oral toxicity) formulations are safe to be used in field applications to efficiently degrade oil palm trunks and root mass that had been felled, chipped or pulverized under zero burning waste management program. This study could also serve as an alternative method for efficient utilization of agro-industrial waste as substrates for the development of cost-effective bio-degraders formulations for agro-waste management.
  2. Molecular characterization of Phytophthora palmivora responsible for bud rot disease of oil palm in Colombia
    Maizatul-Suriza M, Dickinson M, Idris AS
    World J Microbiol Biotechnol, 2019 Feb 27;35(3):44.
    PMID: 30810828 DOI: 10.1007/s11274-019-2618-9
    Bud rot disease is a damaging disease of oil palm in Colombia. The pathogen responsible for this disease is a species of oomyctes, Phytophthora palmivora which is also the causal pathogen of several tropical crop diseases such as fruit rot and stem canker of cocoa, rubber, durian and jackfruit. No outbreaks of bud rot have been reported in oil palm in Malaysia or other Southeast Asian countries, despite this particular species being present in the region. Analysis of the genomic sequences of several genetic markers; the internal transcribe spacer regions (ITS) of the ribosomal RNA gene cluster, beta-tubulin gene, translation elongation factor 1 alpha gene (EF-1α), cytochrome c oxidase subunit I & II (COXI and COXII) gene cluster along with amplified fragment length polymorphism (AFLP) analyses have been carried out to investigate the genetic diversity and variation of P. palmivora isolates from around the world and from different hosts in comparison to Colombian oil palm isolates, as one of the steps in understanding why this species of oomycetes causes devastating damage to oil palm in Latin America but not in other regions. Phylogenetic analyses of these regions showed that the Colombian oil palm isolates were not separated from Malaysian isolates. AFLP analysis and a new marker PPHPAV, targeting an unclassified hypothetical protein, was found to be able to differentiate Malaysian and Colombian isolates and showed a clear clade separations. Despite this, pathogenicity studies did not show any significant differences in the level of aggressiveness of different isolates against oil palm in glasshouse tests.
  3. Involvement of metabolites in early defense mechanism of oil palm (Elaeis guineensis Jacq.) against Ganoderma disease
    Nusaibah SA, Siti Nor Akmar A, Idris AS, Sariah M, Mohamad Pauzi Z
    Plant Physiol Biochem, 2016 Dec;109:156-165.
    PMID: 27694009 DOI: 10.1016/j.plaphy.2016.09.014
    Understanding the mechanism of interaction between the oil palm and its key pathogen, Ganoderma spp. is crucial as the disease caused by this fungal pathogen leads to a major loss of revenue in leading palm oil producing countries in Southeast Asia. Here in this study, we assess the morphological and biochemical changes in Ganoderma disease infected oil palm seedling roots in both resistant and susceptible progenies. Rubber woodblocks fully colonized by G. boninense were applied as a source of inoculum to artificially infect the roots of resistant and susceptible oil palm progenies. Gas chromatography-mass spectrometry was used to measure an array of plant metabolites in 100 resistant and susceptible oil palm seedling roots treated with pathogenic Ganoderma boninense fungus. Statistical effects, univariate and multivariate analyses were used to identify key-Ganoderma disease associated metabolic agitations in both resistant and susceptible oil palm root tissues. Ganoderma disease related defense shifts were characterized based on (i) increased antifungal activity in crude extracts, (ii) increased lipid levels, beta- and gamma-sitosterol particularly in the resistant progeny, (iii) detection of heterocyclic aromatic organic compounds, benzo [h] quinoline, pyridine, pyrimidine (iv) elevation in antioxidants, alpha- and beta-tocopherol (iv) degraded cortical cell wall layers, possibly resulting from fungal hydrolytic enzyme activity needed for initial penetration. The present study suggested that plant metabolites mainly lipids and heterocyclic aromatic organic metabolites could be potentially involved in early oil palm defense mechanism against G. boninense infection, which may also highlight biomarkers for disease detection, treatment, development of resistant variety and monitoring.
  4. Dissipation of the fungicide hexaconazole in oil palm plantation
    Maznah Z, Halimah M, Ismail S, Idris AS
    Environ Sci Pollut Res Int, 2015 Dec;22(24):19648-57.
    PMID: 26276276 DOI: 10.1007/s11356-015-5178-z
    Hexaconazole is a potential fungicide to be used in the oil palm plantation for controlling the basal stem root (BSR) disease caused by Ganoderma boninense. Therefore, the dissipation rate of hexaconazole in an oil palm agroecosystem under field conditions was studied. Two experimental plots were treated with hexaconazole at the recommended dosage of 4.5 g a.i. palm(-1) (active ingredient) and at double the recommended dosage (9.0 g a.i. palm(-1)), whilst one plot was untreated as control. The residue of hexaconazole was detected in soil samples in the range of 2.74 to 0.78 and 7.13 to 1.66 mg kg(-1) at the recommended and double recommended dosage plots, respectively. An initial relatively rapid dissipation rate of hexaconazole residues occurred but reduced with time. The dissipation of hexaconazole in soil was described using first-order kinetics with the value of coefficient regression (r (2) > 0.8). The results indicated that hexaconazole has moderate persistence in the soil and the half-life was found to be 69.3 and 86.6 days in the recommended and double recommended dosage plot, respectively. The results obtained highlight that downward movement of hexaconazole was led by preferential flow as shown in image analysis. It can be concluded that varying soil conditions, environmental factors, and pesticide chemical properties of hexaconazole has a significant impact on dissipation of hexaconazole in soil under humid conditions.
  5. Serine-rich protein is a novel positive regulator for silicon accumulation in mangrove
    Sahebi M, Hanafi MM, Siti Nor Akmar A, Rafii MY, Azizi P, Idris AS
    Gene, 2015 Feb 10;556(2):170-81.
    PMID: 25479011 DOI: 10.1016/j.gene.2014.11.055
    Silicon (Si) plays an important role in reducing plant susceptibility against a variety of different biotic and abiotic stresses; and also has an important regulatory role in soil to avoid heavy metal toxicity and providing suitable growing conditions for plants. A full-length cDNAs of 696bp of serine-rich protein was cloned from mangrove plant (Rhizophora apiculata) by amplification of cDNA ends from an expressed sequence tag homologous to groundnut (Arachis hypogaea), submitted to NCBI (KF211374). This serine-rich protein gene encodes a deduced protein of 223 amino acids. The transcript titre of the serine-rich protein was found to be strongly enriched in roots compared with the leaves of two month old mangrove plants and expression level of this serine-rich protein was found to be strongly induced when the mangrove seedlings were exposed to SiO2. Expression of the serine-rich protein transgenic was detected in transgenic Arabidopsis thaliana, where the amount of serine increased from 1.02 to 37.8mg/g. The same trend was also seen in Si content in the roots (14.3%) and leaves (7.4%) of the transgenic A. thaliana compared to the wild-type plants under Si treatment. The biological results demonstrated that the accumulation of the serine amino acid in the vegetative tissues of the transgenic plants enhanced their ability to absorb and accumulate more Si in the roots and leaves and suggests that the serine-rich protein gene has potential for use in genetic engineering of different stress tolerance characteristics.
  6. Comparison of Different Protein Extraction Methods for Gel-Based Proteomic Analysis of Ganoderma spp
    Al-Obaidi JR, Saidi NB, Usuldin SR, Hussin SN, Yusoff NM, Idris AS
    Protein J, 2016 Apr;35(2):100-6.
    PMID: 27016942 DOI: 10.1007/s10930-016-9656-z
    Ganoderma species are a group of fungi that have the ability to degrade lignin polymers and cause severe diseases such as stem and root rot and can infect economically important plants and perennial crops such as oil palm, especially in tropical countries such as Malaysia. Unfortunately, very little is known about the complex interplay between oil palm and Ganoderma in the pathogenesis of the diseases. Proteomic technologies are simple yet powerful tools in comparing protein profile and have been widely used to study plant-fungus interaction. A critical step to perform a good proteome research is to establish a method that gives the best quality and a wide coverage of total proteins. Despite the availability of various protein extraction protocols from pathogenic fungi in the literature, no single extraction method was found suitable for all types of pathogenic fungi. To develop an optimized protein extraction protocol for 2-DE gel analysis of Ganoderma spp., three previously reported protein extraction protocols were compared: trichloroacetic acid, sucrose and phenol/ammonium acetate in methanol. The third method was found to give the most reproducible gels and highest protein concentration. Using the later method, a total of 10 protein spots (5 from each species) were successfully identified. Hence, the results from this study propose phenol/ammonium acetate in methanol as the most effective protein extraction method for 2-DE proteomic studies of Ganoderma spp.
  7. Fulltext GanoCare® Improves Oil Palm Growth and Resistance against Ganoderma Basal Stem Rot Disease in Nursery and Field Trials
    Rebitanim NA, Hanafi MM, Idris AS, Abdullah SNA, Mohidin H, Rebitanim NZ
    Biomed Res Int, 2020;2020:3063710.
    PMID: 32420335 DOI: 10.1155/2020/3063710
    Basal stem rot (BSR) caused by Ganoderma boninense is a major threat to sustainable oil palm production especially in Southeast Asia and has brought economic losses to the oil palm industry around the world. With no definitive cure at present, this study introduces a new fertilizer technology called GanoCare®, as an effort to suppress BSR incidence in oil palm. Experiments were carried out to evaluate the effect of GanoCare® on growth, physiology, and BSR disease suppression using sitting technique in the oil palm nursery stage. A follow-up using similar treatments was carried out in the field to test on severity of Ganoderma using baiting technique under natural condition. Treatments tested were 10 g/month and 30 g/three months given as pretreatment only or continuous treatment. Results showed that GanoCare® increased the height, bulb diameter, leaf area, chlorophyll content, photosynthesis rate, and fresh and dry weight of the leaf, bole, and root of oil palm seedlings in the nursery trial. Seedlings treated with GanoCare® exhibited reduced percentage of disease severity, incidence, and dead seedlings, compared to the control. In nursery and field, lowest percentage of dead seedlings due to Ganoderma was found in seedlings given combination of pretreatment and continuous treatment of 30 g/three months (T4) with 5.56 and 6.67%, while control seedlings significantly marked the maximum percentage of 94.45 and 93.33%. The most successful treatment in both nursery and field was T4 with disease reductions of 77.78 and 82.36%, respectively, proving that nutrients contained in GanoCare® are essential in allowing better development of a strong defense system in the seedlings.
  8. Fulltext Enhancement of Thiamine Biosynthesis in Oil Palm Seedlings by Colonization of Endophytic Fungus Hendersonia toruloidea
    Kamarudin AN, Lai KS, Lamasudin DU, Idris AS, Balia Yusof ZN
    Front Plant Sci, 2017;8:1799.
    PMID: 29089959 DOI: 10.3389/fpls.2017.01799
    Thiamine, or vitamin B1 plays an indispensable role as a cofactor in crucial metabolic reactions including glycolysis, pentose phosphate pathway and the tricarboxylic acid cycle in all living organisms. Thiamine has been shown to play a role in plant adaptation toward biotic and abiotic stresses. The modulation of thiamine biosynthetic genes in oil palm seedlings was evaluated in response to root colonization by endophytic Hendersonia toruloidea. Seven-month-old oil palm seedlings were inoculated with H. toruloidea and microscopic analyses were performed to visualize the localization of endophytic H. toruloidea in oil palm roots. Transmission electron microscopy confirmed that H. toruloidea colonized cortical cells. The expression of thiamine biosynthetic genes and accumulation of total thiamine in oil palm seedlings were also evaluated. Quantitative real-time PCR was performed to measure transcript abundances of four key thiamine biosynthesis genes (THI4, THIC, TH1, and TPK) on days 1, 7, 15, and 30 in response to H. toruloidea colonization. The results showed an increase of up to 12-fold in the expression of all gene transcripts on day 1 post-inoculation. On days 7, 15, and 30 post-inoculation, the relative expression levels of these genes were shown to be downregulated. Thiamine accumulation was observed on day 7 post-colonization and subsequently decreased until day 30. This work provides the first evidence for the enhancement of thiamine biosynthesis by endophytic colonization in oil palm seedlings.
  9. Fulltext EgJUB1 and EgERF113 transcription factors as potential master regulators of defense response in Elaeis guineensis against the hemibiotrophic Ganoderma boninense
    Sakeh NM, Abdullah SNA, Bahari MNA, Azzeme AM, Shaharuddin NA, Idris AS
    BMC Plant Biol, 2021 Jan 22;21(1):59.
    PMID: 33482731 DOI: 10.1186/s12870-020-02812-7
    BACKGROUND: Hemibiotrophic pathogen such as the fungal pathogen Ganoderma boninense that is destructive to oil palm, manipulates host defense mechanism by strategically switching from biotrophic to necrotrophic phase. Our previous study revealed two distinguishable expression profiles of oil palm genes that formed the basis in deducing biotrophic phase at early interaction which switched to necrotrophic phase at a later stage of infection.

    RESULTS: The present report is a continuing study from our previous published transcriptomic profiling of oil palm seedlings against G. boninense. We focused on identifying differentially expressed genes (DEGs) encoding transcription factors (TFs) from the same RNA-seq data; resulting in 106 upregulated and 108 downregulated TFs being identified. The DEGs are involved in four established defense-related pathways responsible for cell wall modification, reactive oxygen species (ROS)-mediated signaling, programmed cell death (PCD) and plant innate immunity. We discovered upregulation of JUNGBRUNNEN 1 (EgJUB1) during the fungal biotrophic phase while Ethylene Responsive Factor 113 (EgERF113) demonstrated prominent upregulation when the palm switches to defense against necrotrophic phase. EgJUB1 was shown to have a binding activity to a 19 bp palindromic SNBE1 element, WNNYBTNNNNNNNAMGNHW found in the promoter region of co-expressing EgHSFC-2b. Further in silico analysis of promoter regions revealed co-expression of EgJUB1 with TFs containing SNBE1 element with single nucleotide change at either the 5th or 18th position. Meanwhile, EgERF113 binds to both GCC and DRE/CRT elements promoting plasticity in upregulating the downstream defense-related genes. Both TFs were proven to be nuclear-localized based on subcellular localization experiment using onion epidermal cells.

    CONCLUSION: Our findings demonstrated unprecedented transcriptional reprogramming of specific TFs potentially to enable regulation of a specific set of genes during different infection phases of this hemibiotrophic fungal pathogen. The results propose the intricacy of oil palm defense response in orchestrating EgJUB1 during biotrophic and EgERF113 during the subsequent transition to the necrotrophic phase. Binding of EgJUB1 to SNBE motif instead of NACBS while EgERF113 to GCC-box and DRE/CRT motifs is unconventional and not normally associated with pathogen infection. Identification of these phase-specific oil palm TFs is important in designing strategies to tackle or attenuate the progress of infection.

  10. Control of Basal Stem Rot Disease in Oil Palm by Supplementation of Calcium, Copper, and Salicylic Acid
    Bivi MS, Paiko AS, Khairulmazmi A, Akhtar MS, Idris AS
    Plant Pathol J, 2016 Oct;32(5):396-406.
    PMID: 27721689
    Continuous supplementation of mineral nutrients and salicylic acid (SA) as foliar application could improve efficacy in controlling basal stem rot (BSR) disease in oil palm seedling. It is revealed from the results that the highest disease severity index (58.3%) was recorded in T8 treatments at 9 months after inoculation. The best disease control was achieved by T7 treatments (calcium/copper/SA [Ca/Cu/SA]) (5.0%) followed by T1 (5.5%), T5 (5.8%), T3 (8.3%), T6 (8.3%), T4 (13.3%), and T2 (15.8%) treatments. Continuous supplementation of Ca/Cu/SA was found to be the most effective in controlling the disease and the high performance liquid chromatography results showed the detection of ergosterol at very low concentration in the treated samples. Moreover, the transmission electron microscopy analysis results clearly indicated that T7 treatment was also enhancing lignification, which was responsible for the thickness of the secondary cell walls and middle lamella compared to untreated samples. It was therefore, concluded that continuous supplementation of minerals nutrients and SA could effectively suppress disease severity by reducing ergosterol activity and also improve the process of lignification in the treated plants. Furthermore, this treatment also managed to delay the onset of BSR symptoms and promote the growth of the seedlings and eventually suppress the BSR disease.
  11. Fulltext Identification of Oil Palm's Consistently Upregulated Genes during Early Infections of Ganoderma boninense via RNA-Seq Technology and Real-Time Quantitative PCR
    Zuhar LM, Madihah AZ, Ahmad SA, Zainal Z, Idris AS, Shaharuddin NA
    Plants (Basel), 2021 Sep 27;10(10).
    PMID: 34685835 DOI: 10.3390/plants10102026
    Basal stem rot (BSR) disease caused by pathogenic fungus Ganoderma boninense is a significant concern in the oil palm industry. G. boninense infection in oil palm induces defense-related genes. To understand oil palm defense mechanisms in response to fungal invasion, we analyzed differentially expressed genes (DEGs) derived from RNA-sequencing (RNA-seq) transcriptomic libraries of oil palm roots infected with G. boninense. A total of 126 DEGs were detected from the transcriptomic libraries of G. boninense-infected root tissues at different infection stages. Functional annotation via pathway enrichment analyses revealed that the DEGs were involved in the defense response against the pathogen. The expression of the selected DEGs was further confirmed using real-time quantitative PCR (qPCR) on independent oil palm seedlings and mature palm samples. Seven putative defense-related DEGs consistently showed upregulation in seedlings and mature plants during G. boninense infection. These seven genes might potentially be developed as biomarkers for the early detection of BSR in oil palm.
  12. Fulltext Hexaconazole-Micelle Nanodelivery System Prepared Using Different Surfactants for Ganoderma Antifungal Application
    Mustafa IF, Hussein MZ, Idris AS, Hilmi NHZ, Fakurazi S
    Molecules, 2021 Sep 26;26(19).
    PMID: 34641379 DOI: 10.3390/molecules26195837
    Reports on fungicide-based agronanochemicals in combating disastrous basal stem rot disease in the oil palm industry are scant. Herein, we describe the potential of fungicide nanodelivery agents based on hexaconazole-micelle systems produced using three different surfactants; sodium dodecylbenze sulfonate (SDBS), sodium dodecyl sulfate (SDS) and Tween 80 (T80). The resulting nanodelivery systems were characterized and the results supported the encapsulation of the fungicide into the micelles of the surfactants. We have investigated in detail the size-dependent effects of the as-synthesized micelles towards the inhibition growth of Ganoderma Boninense fungi. All the nanodelivery systems indicate that their size decreased as the surfactant concentration was increased, and it directly affects the fungal inhibition. It was also found that Tween 80, a non-ionic surfactant gave the lowest effective concentration, the EC50 value of 2, on the pathogenic fungus Ganoderma boninense compared to the other anionic surfactants; SDBS and SDS. This study opens up a new generation of agronanofungicide of better efficacy for Ganoderma disease treatment.
  13. Characterization of Streptomyces spp. isolated from the rhizosphere of oil palm and evaluation of their ability to suppress basal stem rot disease in oil palm seedlings when applied as powder formulations in a glasshouse trial
    Shariffah-Muzaimah SA, Idris AS, Madihah AZ, Dzolkhifli O, Kamaruzzaman S, Maizatul-Suriza M
    World J Microbiol Biotechnol, 2017 Dec 18;34(1):15.
    PMID: 29256103 DOI: 10.1007/s11274-017-2396-1
    Ganoderma boninense, the main causal agent of oil palm (Elaeis guineensis) basal stem rot (BSR), severely reduces oil palm yields around the world. To reduce reliance on fungicide applications to control BSR, we are investigating the efficacy of alternative control methods, such as the application of biological control agents. In this study, we used four Streptomyces-like actinomycetes (isolates AGA43, AGA48, AGA347 and AGA506) that had been isolated from the oil palm rhizosphere and screened for antagonism towards G. boninense in a previous study. The aim of this study was to characterize these four isolates and then to assess their ability to suppress BSR in oil palm seedlings when applied individually to the soil in a vermiculite powder formulation. Analysis of partial 16S rRNA gene sequences (512 bp) revealed that the isolates exhibited a very high level of sequence similarity (> 98%) with GenBank reference sequences. Isolates AGA347 and AGA506 showed 99% similarity with Streptomyces hygroscopicus subsp. hygroscopicus and Streptomyces ahygroscopicus, respectively. Isolates AGA43 and AGA48 also belonged to the Streptomyces genus. The most effective formulation, AGA347, reduced BSR in seedlings by 73.1%. Formulations using the known antifungal producer Streptomyces noursei, AGA043, AGA048 or AGA506 reduced BSR by 47.4, 30.1, 54.8 and 44.1%, respectively. This glasshouse trial indicates that these Streptomyces spp. show promise as potential biological control agents against Ganoderma in oil palm. Further investigations are needed to determine the mechanism of antagonism and to increase the shelf life of Streptomyces formulations.
  14. Synthesis of (Hexaconazole-Zinc/Aluminum-Layered Double Hydroxide Nanocomposite) Fungicide Nanodelivery System for Controlling Ganoderma Disease in Oil Palm
    Mustafa IF, Hussein MZ, Saifullah B, Idris AS, Hilmi NHZ, Fakurazi S
    J Agric Food Chem, 2018 Jan 31;66(4):806-813.
    PMID: 29281878 DOI: 10.1021/acs.jafc.7b04222
    A fungicide, hexaconazole was successfully intercalated into the intergalleries of zinc/aluminum-layered double hydroxide (ZALDH) using the ion-exchange method. Due to the intercalation of hexaconazole, the basal spacing of the ZALDH was increased from 8.7 Å in ZALDH to 29.4 Å in hexaconazole-intercalated ZALDH (HZALDH). The intercalation of hexaconazole into the interlayer of the nanocomposite was confirmed using the Fourier-transform infrared (FTIR) study. This supramolecular chemistry intercalation process enhanced the thermal stability of the hexaconazole moiety. The fungicide loading was estimated to be 51.8%. The nanodelivery system also shows better inhibition toward the Ganoderma boninense growth than the counterpart, free hexaconazole. The results from this work have a great potential to be further explored for combating basal stem rot (BSR) disease in oil palm plantation.
  15. Fulltext Isolation and expression analysis of novel silicon absorption gene from roots of mangrove (Rhizophora apiculata) via suppression subtractive hybridization
    Sahebi M, Hanafi MM, Abdullah SN, Rafii MY, Azizi P, Nejat N, et al.
    Biomed Res Int, 2014;2014:971985.
    PMID: 24516858 DOI: 10.1155/2014/971985
    Silicon (Si) is the second most abundant element in soil after oxygen. It is not an essential element for plant growth and formation but plays an important role in increasing plant tolerance towards different kinds of abiotic and biotic stresses. The molecular mechanism of Si absorption and accumulation may differ between plants, such as monocotyledons and dicotyledons. Silicon absorption and accumulation in mangrove plants are affected indirectly by some proteins rich in serine and proline amino acids. The expression level of the genes responsible for Si absorption varies in different parts of plants. In this study, Si is mainly observed in the epidermal roots' cell walls of mangrove plants compared to other parts. The present work was carried out to discover further information on Si stress responsive genes in Rhizophora apiculata, using the suppression subtractive hybridization technique. To construct the cDNA library, two-month-old seedlings were exposed to 0.5, 1, and 1.5 mM SiO2 for 15 hrs and for 1 to 6 days resulting in a total of 360 high quality ESTs gained. Further examination by RT-PCR and real-time qRT-PCR showed the expression of a candidate gene of serine-rich protein.
  16. Fulltext Preparation of Chitosan-Hexaconazole Nanoparticles as Fungicide Nanodelivery System for Combating Ganoderma Disease in Oil Palm
    Maluin FN, Hussein MZ, Yusof NA, Fakurazi S, Idris AS, Zainol Hilmi NH, et al.
    Molecules, 2019 Jul 08;24(13).
    PMID: 31288497 DOI: 10.3390/molecules24132498
    Fungicide is used to control fungal disease by destroying and inhibiting the fungus or fungal spores that cause the disease. However, failure to deliver fungicide to the disease region leads to ineffectiveness in the disease control. Hence, in the present study, nanotechnology has enabled the fungicide active agents (hexaconazole) to be encapsulated into chitosan nanoparticles with the aim of developing a fungicide nanodelivery system that can transport them more effectively to the target cells (Ganoderma fungus). A pathogenic fungus, Ganoderma boninense (G. boninense), is destructive to oil palm whereby it can cause significant loss to oil palm plantations located in the Southeast Asian countries, especially Malaysia and Indonesia. In regard to this matter, a series of chitosan nanoparticles loaded with the fungicide, hexaconazole, was prepared using various concentrations of crosslinking agent sodium tripolyphosphate (TPP). The resulting particle size revealed that the increase of the TPP concentration produced smaller particles. In addition, the in vitro fungicide released at pH 5.5 demonstrated that the fungicide from the nanoparticles was released in a sustainable manner with a prolonged release time up to 86 h. On another note, the in vitro antifungal studies established that smaller particle size leads to lower half maximum effective concentration (EC50) value, which indicates higher antifungal activity against G. boninense.
  17. Fulltext Residual analysis of chitosan-based agronanofungicides as a sustainable alternative in oil palm disease management
    Maluin FN, Hussein MZ, Yusof NA, Fakurazi S, Maznah Z, Idris AS, et al.
    Sci Rep, 2020 12 18;10(1):22323.
    PMID: 33339951 DOI: 10.1038/s41598-020-79335-6
    The nanoformulations of pesticides have shown great interest from many parties due to their slow release capability and site-specific delivery. Hence, in this work, a new nanoformulation of a fungicide, namely chitosan-hexaconazole nanoparticles with a mean diameter size of 18 nm was subjected to the residual analysis on oil palm tissue, leaf and palm oil (crude palm oil and crude palm kernel oil) using a quick, easy, cheap, effective, rugged and safe (QuEChERS) method coupled with the gas chromatography-micro electron capture detector (GC-µECD). The chitosan-hexaconazole nanoparticles were applied using the trunk injection method at 4.5 g a.i./palm (standard single dose) and 9.0 g a.i./palm (double dose). The fungicide residue was analyzed at 0 (6 h after application), 1, 3, 7, 14, 30, 60, 90, and 120 days after treatment. The palm oil matrices; the crude palm oil (CPO) and crude palm kernel oil (CPKO) were found to be residue-free. However, it was observed that high accumulation of the fungicide in the stem tissue and leaf after the treatment using the chitosan-hexaconazole nanoparticles, which is good for better bioavailability for the treatment of the fungi, Ganoderma boninense. The dissipation kinetic at double dose treatment in the tissue and leaf was found to govern by the second-order kinetic with half-lives (t1/2) of 383 and 515 days, respectively.
  18. Fulltext Willingness to treat COVID-19 disease: What do medical & nursing students perceive?
    Cheah WL, Francis Wing CB, Zahari AN, Idris AS, Maksul NAA, Yusman NAL, et al.
    Ethics Med Public Health, 2021 Jun;17:100651.
    PMID: 33754125 DOI: 10.1016/j.jemep.2021.100651
    Background: The COVID-19 pandemic has resulted in many changes in the delivery of health service which not only affect the public as well as healthcare workers, and also among medical and nursing students who are currently undergoing their training. This study aims to determine the commitment and willingness of medical and nursing students in Sarawak in treating patients with COVID-19 and its associated factors.

    Methods: It was a cross-sectional study using online questionnaire, carried out in a public university in Sarawak, Malaysia. All medical and nursing students were invited to participate in this study. Data was entered and analysed using IBM SPSS version 22.

    Result: A total of 304 respondents participated in the study, with 81.6% female and 69.4% medical students. Majority of the respondents were most willing to take a medical history, do a physical examination, throat swabbing, draw blood and perform IV drip insertion. There was a high commitment among respondents to treat COVID-19 patients regardless of personal risks. Majority of the respondents also agreed that medical staff who are involved in treating COVID-19 patients should be receiving a salary increase and compensation should be given to affected healthcare families, and all non-medical staff should be involved in treating COVID-19 patients. About 71% agreed about a law mandating medical staffs to treat patient.

    Conclusion: The willingness and commitment of medical and nursing students to treat COVID-19 patients was high, indicating their potential work force as healthcare providers.

  19. Fulltext Transcriptome datasets of oil palm pathogen Ganoderma boninense
    Isaac IL, Walter AWCY, Bakar MFA, Idris AS, Bakar FDA, Bharudin I, et al.
    Data Brief, 2018 Apr;17:1108-1111.
    PMID: 29876468 DOI: 10.1016/j.dib.2018.02.027
    Ganoderma boninense is known to be the causal agent for basal stem rot (BSR) affecting the oil palm industry worldwide thus cumulating to high economic losses every year. Several reports have shown that a compatible monokaryon pair needs to mate; producing dikaryotic mycelia to initiate the infection towards the oil palm. However, the molecular events occurs during mating process are not well understood. We performed transcriptome sequencing using Illumina RNA-seq technology and de novo assembly of the transcripts from monokaryon, mating junction and dikaryon mycelia of G. boninense. Raw reads from these three libraries were deposited in the NCBI database with accession number SRR1745787, SRR1745773 and SRR1745777, respectively.
  20. Fulltext Antioxidant Enzyme Activities and Secondary Metabolite Profiling of Oil Palm Seedlings Treated with Combination of NPK Fertilizers Infected with Ganoderma boninense
    Sahebi M, Hanafi MM, Mohidin H, Rafii MY, Azizi P, Idris AS, et al.
    Biomed Res Int, 2018;2018:1494157.
    PMID: 29721500 DOI: 10.1155/2018/1494157
    Oil palm (Elaeis guineensis Jacq) is one of the major sources of edible oil. Reducing the effect of Ganoderma, main cause of basal stem rot (BSR) on oil palm, is the main propose of this study. Understanding the oil palm defense mechanism against Ganoderma infection through monitoring changes in the secondary metabolite compounds levels before/after infection by Ganoderma under different fertilizing treatment is required. Oil palm requires macro- and microelements for growth and yield. Manipulating the nutrient for oil palm is a method to control the disease. The 3-4-month-old oil palm seedlings were given different macronutrient treatments to evaluate induction of defense related enzymes and production of secondary metabolite compounds in response to G. boninense inoculation. The observed trend of changes in the infected and uninfected seedlings was a slightly higher activity for β-1,3-glucanases, chitinase, peroxidase, and phenylalanine ammonia-lyase during the process of pathogenesis. It was found that PR proteins gave positive response to the interaction between oil palm seedlings and Ganoderma infection. Although the responses were activated systematically, they were short-lasting as the changes in enzymes activities appeared before the occurrence of visible symptoms. Effect of different nutrients doses was obviously observed among the results of the secondary metabolite compounds. Many identified/unidentified metabolite compounds were presented, of which some were involved in plant cell defense mechanism against pathogens, mostly belonging to alkaloids with bitter-tasting nitrogenous-compounds, and some had the potential to be used as new markers to detect basal stem rot at the initial step of disease.
Related Terms
Filters
Contact Us

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

External Links