Displaying publications 1 - 20 of 164 in total

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  1. Lee SC, Hashim R, Motamedi S, Song KI
    ScientificWorldJournal, 2014;2014:494020.
    PMID: 24955408 DOI: 10.1155/2014/494020
    Threats to beaches have accelerated the coastal destruction. In recent decades, geotextile tubes were used around the world to prevent coastal erosion, to encourage beach nourishment, and to assist mangrove rehabilitation. However, the applications of geotextile tube in sandy and muddy coasts have different concerns as the geological settings are different. Applications of geotextile tubes in sandy beaches were mainly to prevent coastline from further erosion and to nourish the beach. However, for the muddy coasts, mangrove rehabilitation and conservation were additional concerns in coastal management schemes. The mangrove forests are natural barriers which can be found on the muddy coasts of many tropical countries. In this paper, the viability of geotextile tubes in sandy and muddy beaches was analysed. The advantages and disadvantages of the utilization of geotextile tubes in coastal management were discussed based on the experiences from the tropical countries such as Mexico, Malaysia, and Thailand. From the case studies, impressive improvements in coastal restoration after installation of geotextile tubes were shown. Based on the discussion, several recommendations to improve the application of geotextile tubes were suggested in this paper.
  2. Wilson JJ, Sing KW, Halim MR, Ramli R, Hashim R, Sofian-Azirun M
    Genet. Mol. Res., 2014;13(1):920-5.
    PMID: 24634112 DOI: 10.4238/2014.February.19.2
    Bats are important flagship species for biodiversity research; however, diversity in Southeast Asia is considerably underestimated in the current checklists and field guides. Incorporation of DNA barcoding into surveys has revealed numerous species-level taxa overlooked by conventional methods. Inclusion of these taxa in inventories provides a more informative record of diversity, but is problematic as these species lack formal description. We investigated how frequently documented, but undescribed, bat taxa are encountered in Peninsular Malaysia. We discuss whether a barcode library provides a means of recognizing and recording these taxa across biodiversity inventories. Tissue was sampled from bats trapped at Pasir Raja, Dungun Terengganu, Peninsular Malaysia. The DNA was extracted and the COI barcode region amplified and sequenced. We identified 9 species-level taxa within our samples, based on analysis of the DNA barcodes. Six specimens matched to four previously documented taxa considered candidate species but currently lacking formal taxonomic status. This study confirms the high diversity of bats within Peninsular Malaysia (9 species in 13 samples) and demonstrates how DNA barcoding allows for inventory and documentation of known taxa lacking formal taxonomic status.
  3. Billen J, Hashim R, Ito F
    PMID: 27130260 DOI: 10.1016/j.asd.2016.04.003
    The mandibular gland in workers of the formicine ant Myrmoteras iriodum differs from other ants both in its general morphology and ultrastructural organization. The secretory cells appear in a pseudo-epithelial arrangement that gives them a clear polarity. At their apical side, the cells are characterized by a large cup-like extension of the reservoir, from which a bulbous invagination connects to a branched end apparatus. At the basal side, the cells show a labyrinth of basal invaginations, while the lateral cell contacts show clear interdigitations. The cytoplasmic composition reveals the presence of numerous round or elongate inclusions that contain crystalline material. Microtubules are abundant, and locally fibrillar regions are found. The function of the mandibular gland in M. iriodum has not yet been documented, and should be studied using gland extracts and behavioural observations.
  4. Takaoka H, Sofian-Azirun M, Hashim R, Yacob Z, Chen CD
    J Med Entomol, 2012 Jul;49(4):803-12.
    PMID: 22897040
    Two new species of black flies, Simulium (Comphostilbia) terengganuense sp. nov. and Simulium (Gomphostilbia) aziruni sp. nov. (Diptera: Simuliidae), are described on the basis of reared adult, pupal, and larval specimens collected from Peninsular Malaysia. Both species are placed in the batoense species-group within the subgenus Gomphostilbia, one of two dominant subgenera of the genus Simulium in Peninsular Malaysia as well as in the Oriental Region. Strikingly, three morphological characteristics that rarely occur in the subgenus Gomphostilbia are found in these two new species: the very narrow female frons and the mushroom-like pupal terminal hooks in S. (G.) terengganuense sp. nov. and the pupal gill composed of an inflated horn-like structure and eight slender filaments in S. (G.) aziruni sp. nov.
  5. Takaoka H, Sofian-Azirun M, Ya'cob Z, Hashim R
    Zootaxa, 2014;3765:54-68.
    PMID: 24870884 DOI: 10.11646/zootaxa.3765.1.3
    Two new black fly species, Simulium (Gomphostilbia) brinchangense and S. (G.) tanahrataense, are described on the basis of reared adult females, males, pupae and larvae from Cameron's Highlands, Peninsular Malaysia. These new species are assigned to the asakoae species-group within Simulium (Gomphostilbia) and taxonomic notes are given to distinguish each new species from six known species in Malaysia. Revised keys to identify all 21 species including 13 species from other countries are provided for females, males, pupae and mature larvae. The species diversity of the asakoae species-group in Cameron's Highlands is briefly noted.
  6. Takaoka H, Sofian-Azirun M, Hashim R, Ya'cob Z
    Zookeys, 2011.
    PMID: 21998510 DOI: 10.3897/zookeys.118.1552
    Two new species of black flies, Simulium (Gomphostilbia) roslihashimisp. n. and Simulium (Gomphostilbia) lurauensesp. n., are described on the basis of reared adult, pupal and larval specimens collected from Peninsular Malaysia. These two new species are placed in the ceylonicum species-group within the subgenus Gomphostilbia. Simulium (Gomphostilbia) roslihashimisp. n. is most distinctive with the male having almost entirely yellow antennae, and Simulium (Gomphostilbia) lurauensesp. n. is characterized in the female by having the elongate sensory vesicle and the yellowish-white hairs on the base of the costal vein and on the stem vein, in the male by the greater number of large upper-eye facets and the spindle-shaped hind basitarsi which are much narrower than the hind tibiae and femora and in the pupa by the small terminal hooks. Keys to species of the ceylonicum species-group reported from Peninsular Malaysia are provided for females, males, pupae and mature larvae.
  7. Tajul Baharuddin MF, Taib S, Hashim R, Zainal Abidin MH, Ishak MF
    Environ Monit Assess, 2011 Sep;180(1-4):345-69.
    PMID: 21136290 DOI: 10.1007/s10661-010-1792-x
    Time-lapse resistivity measurements and groundwater geochemistry were used to study salinity effect on groundwater aquifer at the ex-promontory-land of Carey Island in Malaysia. Resistivity was measured by ABEM Terrameter SAS4000 and ES10-64 electrode selector. Relationship between earth resistivity and total dissolved solids (TDS) was derived, and with resistivity images, used to identify water types: fresh (ρ ( e ) > 6.5 Ω m), brackish (3 Ω m < ρ ( e ) < 6.5 Ω m), or saline (ρ ( e ) < 3 Ω m). Long-term monitoring of the studied area's groundwater quality via measurements of its time-lapse resistivity showed salinity changes in the island's groundwater aquifers not conforming to seawater-freshwater hydraulic gradient. In some aquifers far from the coast, saline water was dominant, while in some others, freshwater 30 m thick showed groundwater potential. Land transformation is believed to have changed the island's hydrogeology, which receives saltwater pressure all the time, limiting freshwater recharge to the groundwater system. The time-lapse resistivity measurements showed active salinity changes at resistivity-image bottom moving up the image for two seasons' (wet and dry) conditions. The salinity changes are believed to have been caused by incremental tide passing through highly porous material in the active-salinity-change area. The study's results were used to plan a strategy for sustainable groundwater exploration of the island.
  8. Ahmad T, Danish M, Rafatullah M, Ghazali A, Sulaiman O, Hashim R, et al.
    Environ Sci Pollut Res Int, 2012 Jun;19(5):1464-84.
    PMID: 22207239 DOI: 10.1007/s11356-011-0709-8
    BACKGROUND: In tropical countries, the palm tree is one of the most abundant and important trees. Date palm is a principal fruit grown in many regions of the world. It is abundant, locally available and effective material that could be used as an adsorbent for the removal of different pollutants from aqueous solution.

    REVIEW: This article presents a review on the role of date palm as adsorbents in the removal of unwanted materials such as acid and basic dyes, heavy metals, and phenolic compounds. Many studies on adsorption properties of various low cost adsorbent, such as agricultural waste and activated carbons based on agricultural waste have been reported in recent years.

    CONCLUSION: Studies have shown that date palm-based adsorbents are the most promising adsorbents for removing unwanted materials. No previous review is available where researchers can get an overview of the adsorption capacities of date palm-based adsorbent used for the adsorption of different pollutants. This review provides the recent literature demonstrating the usefulness of date palm biomass-based adsorbents in the adsorption of various pollutants.

  9. Peyman N, Tavakoly Sany SB, Tajfard M, Hashim R, Rezayi M, Karlen DJ
    Environ Sci Process Impacts, 2017 Aug 16;19(8):1086-1103.
    PMID: 28776620 DOI: 10.1039/c7em00200a
    A set of methodological tools was tested to assess the sensitivity of several ecological and biological indices to eutrophication while at the same time attempting to explore a linkage among pressures, classification assessment and drivers. Industrial discharges, harbor activities, natural interactions and river discharges are the pressures most related to the eutrophication process in tropical coastal water bodies. Among the eutrophication indices used, TRIX and operational indicators overestimated the eutrophication status in the study area, but EI and chl-a seems to be a rather responsive index to reflect the first stage of eutrophication. It is noteworthy that EI and chl-a showed better overall agreement with the ecological quality status (EcoQ) showing that probably it reflects the indirect relation of macrobenthic with water eutrophication in a better way. An ecological boundary of EI and chl-a from moderate to poor may be needed in order to explain the poor status of relatively eutrophic Klang Strait coastal sites.
  10. Awang-Hashim R, Kaur A, Noman M
    J Adolesc, 2015 Dec;45:214-24.
    PMID: 26513126 DOI: 10.1016/j.adolescence.2015.10.001
    The study examined a conceptual model integrating existing knowledge on the linkages between life satisfaction, affect, purpose in life, and resilience with school engagement. This model posits direct relationships between all the social psychological variables and school engagement, and also indirect relationships between life satisfaction and school engagement as mediated by all the other variables in the study. The participants were 2381 students (1119 boys and 1262 girls) with average age of 15 years, from 40 national secondary schools in Malaysia. The findings supported the theoretical conceptualization. All variables were positively associated with school engagement. The strongest relationship was observed between overall life satisfaction and school engagement. The mediating model was partially supported. The study reiterates the adage that "it takes a village to raise a child". Implications for practice and future research are discussed in the context of engagement in school learning.
  11. Bakar NA, Jayah NI, Mohamed NR, Ali SM, Nasir SH, Hashim R, et al.
    J World Fed Orthod, 2020 03;9(1):3-8.
    PMID: 32672665 DOI: 10.1016/j.ejwf.2019.11.004
    INTRODUCTION: Gingivitis is one of the commonest problems faced by patients with fixed appliances (FA) as there is close relation between the appliances to gingival sulcus. Stichopus horrens (SH) is a sea cucumber from the Indo-Pacific that has medical healing properties which have been traditionally used.

    OBJECTIVE: To assess the effects of toothpaste containing aqueous SH extract on plaque-induced gingivitis following orthodontic bond-up and to identify the optimal concentration of SH.

    METHODS: A single-centred; triple-blinded randomized controlled trial conducted in 40 patients with FA. Participants were randomly assigned to one of the four groups with toothpaste which has concentration of SH extract of 0%, 3%, 6% or 9%. The statistician, the participants and the researchers involved in data collection were kept blinded from the allocation. Gingival Index (GI) and Bleeding on Probing (BOP) for each group were taken at day 0,7,14 and 30.

    RESULTS: 9% of SH-containing toothpaste (SHCT) showed most substantial result as there were significance difference of GI (P = 0.020) from Day 7 to 14 and from Day 0 to 14 (P = 0.020). There was also significance difference of BOP from Day 0 to 14 (P = 0.022) and from Day 0 to 30 (P = 0.027). Significant difference was seen in 3% of SHCT group with the decrease of GI (P = 0.004) from Day 1 to 14. There were no significant difference noted for 0% and 6% SHCT.

    CONCLUSION: The 9% SHCT is the most effective concentration to reduce both the gingival inflammation (up to day 14) and bleeding on probing (up to day 30).

  12. Nainggolan I, Radiman S, Hamzah AS, Hashim R
    Colloids Surf B Biointerfaces, 2009 Oct 1;73(1):84-91.
    PMID: 19540095 DOI: 10.1016/j.colsurfb.2009.05.021
    Two novel glycolipids have been synthesized and their phase behaviour studied. They have been characterized using FT-IR, FAB and 13C NMR and 1H NMR to ensure the purity of novel glycolipids. The two glycolipids are distinguished based on the head group of glycolipids (monosaccharide/glucose and disaccharide/maltose). These two novel glycolipids have been used as surfactant to perform two phase diagrams. Phase behaviours that have been investigated are 2-hexyldecyl-beta-D-glucopyranoside (2-HDG)/n-octane/water ternary system and 2-hexyldecyl-beta-D-maltoside (2-HDM)/n-octane/water ternary system. SAXS and polarizing optical microscope have been used to study the phase behaviours of these two surfactants in ternary phase diagram. Study of effect of the head group on branched-alkyl chain surfactants in ternary system is a strategy to derive the structure-property relationship. For comparison, 2-HDM and 2-HDG have been used as surfactant in the same ternary system. The phase diagram of 2-hexyldecyl-beta-D-maltoside/n-octane/water ternary system exhibited a Lalpha phase at a higher concentration regime, followed with two phases and a micellar solution region in a lower concentration regime. The phase diagram of 2-HDG/water/n-octane ternary system shows hexagonal phase, cubic phase, rectangular ribbon phase, lamellar phase, cubic phase as the surfactant concentration increase.
  13. Ahmad N, Hashim R, Mohd Noor A
    Int J Microbiol, 2013;2013:121845.
    PMID: 24194761 DOI: 10.1155/2013/121845
    Acute melioidosis may present as localised or septicaemic infections and can be fatal if left untreated. Burkholderia pseudomallei resistant to antibiotics used for the treatment of melioidosis had been reported. The aim of this study was to determine the in vitro antibiotic susceptibility patterns of Burkholderia pseudomallei isolated in Malaysia to a panel of antibiotics used for the treatment of melioidosis and also to potential alternative antibiotics such as tigecycline, ampicillin/sulbactam, and piperacillin/tazobactam. A total of 170 Burkholderia pseudomallei isolates were subjected to minimum inhibitory concentration determination using E-test method to eleven antibiotics. All isolates were sensitive to meropenem and piperacillin/tazobactam. For ceftazidime, imipenem, amoxicillin/clavulanic acid, and doxycycline resistance was observed in 1 isolate (0.6%) for each of the antibiotics. Trimethoprim/sulfamethoxazole resistance was observed in 17 (10%) isolates. For other antibiotics, ampicillin/sulbactam, chloramphenicol, tigecycline, and ciprofloxacin resistance were observed in 1 (0.6%), 6 (3.5%), 60 (35.3%) and 98 (57.7%) isolates respectively. One isolate B170/06 exhibited resistance to 4 antibiotics, namely, ciprofloxacin, chloramphenicol, trimethoprim/sulfamethoxazole, and tigecycline. In conclusion, the Malaysian isolates were highly susceptible to the current antibiotics used in the treatment of melioidosis in Malaysia. Multiple resistances to the antibiotics used in the maintenance therapy are the cause for a concern.
  14. A Wahab I, Goh KW, Zainal ZA, Mohamed Yusof NS, Huri HZ, Jacob SA, et al.
    Int J Environ Res Public Health, 2022 Aug 05;19(15).
    PMID: 35954990 DOI: 10.3390/ijerph19159629
    The global depression burden has remained a challenge throughout the pre- and post-pandemic era. The pandemic effect has led to the spiraling of mental disorders among young people who will be the next generation of leaders. This study aims to identify university students’ sociodemographic, psychosocial and academic backgrounds and performance associated with depression symptoms for the development of primary and secondary preventive strategies for mental health. A cross-sectional study was conducted using an online questionnaire distributed to 19 institutions in Malaysia offering a Bachelor of Pharmacy degree program. The self-rated Depression Anxiety Stress Scale (DASS-42) was used to assess depression symptoms. Pearson’s chi-square test and Fisher’s exact test were used to assess the investigated variables with depression symptoms. Independent T-test and one-way ANOVA were used to compare means of depression score across variables. Binary logistic regression was employed to examine the relationship between the investigated variables and depression symptoms. A total of 610 pharmacy students participated, of which 47% (n = 289/610) were having depression symptoms. Students who smoke nicotine and those who have separated parents, family history of mental illness, and poor academic performance were associated with depression symptoms (p < 0.05). Differences in geographical areas, race and religion also showed significant associations with depression symptoms. Parental marital status, poor academic performance, history of mental illness and comorbidities were statistically predicting depression symptoms (p < 0.05). Primary preventive strategies allowing students to harness healthy coping skills for stress, nicotine-free campaigns and a holistic curriculum are warranted. Secondary measures on mindfulness and compassion skills activities to benefit students who experienced early life crises are highly recommended. Enforcing these targeted strategies in collaboration with health and social sectors should be the primary agenda of universities to ensure their uptake.
  15. Salim M, Wan Iskandar WF, Patrick M, Zahid NI, Hashim R
    Langmuir, 2016 06 07;32(22):5552-61.
    PMID: 27183393 DOI: 10.1021/acs.langmuir.6b01007
    Inverse bicontinuous cubic phases of lyotropic liquid crystal self-assembly have received much attention in biomedical, biosensing, and nanotechnology applications. An Ia3d bicontinuous cubic based on the gyroid G-surface can be formed by the Guerbet synthetic glucolipid 2-hexyl-decyl-β-d-glucopyranoside (β-Glc-OC6C10) in excess water. The small water channel diameter of this cubic phase could provide nanoscale constraints in encapsulation of large molecules and crystallization of membrane proteins, hence stresses the importance of water channel tuning ability. This work investigates the swelling behavior of lyotropic self-assembly of β-Glc-OC6C10 which could be controlled and modulated by different surfactants as a hydration-modulating agent. Our results demonstrate that addition of nonionic glycolipid octyl-β-d-glucopyranoside (β-Glc-OC8) at 20 and 25 mol % gives the largest attainable cubic water channel diameter of ca. 62 Å, and formation of coacervates which may be attributed to a sponge phase were seen at 20 mol % octyl-β-d-maltopyranoside (β-Mal-OC8). Swelling of the cubic water channel can also be attained in charged surfactant-doped systems dioctyl sodium sulfosuccinate (AOT) and hexadecyltrimethylammonium bromide (CTAB), of which phase transition occurred from cubic to a lamellar phase. Destabilization of the cubic phase to an inverse hexagonal phase was observed when a high amount of charged lecithin (LEC) and stearylamine (SA) was added to the lipid self-assembly.
  16. Billen J, Bauweleers E, Hashim R, Ito F
    Arthropod Struct Dev, 2013 May;42(3):173-83.
    PMID: 23333930 DOI: 10.1016/j.asd.2013.01.001
    We studied the exocrine system of both workers and ergatoid queens of Protanilla wallacei using light, scanning and transmission electron microscopy. Our survey revealed the presence of 26 glands, of which 6 had never been found before in ants. Five of these represent novel discoveries for social insects in general. The overall novel discoveries comprise an epithelial stipes gland, a pharyngeal wall gland, a central petiole gland, a lateral postpetiole gland and a foot-sole gland in the hindleg pretarsi. The intramandibular epithelial gland was already reported in some bees previously, but is now for the first time also reported in ants. The exocrine system of workers and ergatoid queens is very similar, with only the spermathecal gland showing an obvious difference. This is in line with the limited anatomical as well as behavioural difference between both castes in Protanilla compared to the situation in Leptanilla.
  17. Mohd Tap R, Sabaratnam P, Ramli NY, Hashim R, Mohd Fuat AR, Ng PP, et al.
    Mycopathologia, 2016 Apr;181(3-4):285-90.
    PMID: 26493614 DOI: 10.1007/s11046-015-9958-2
    Trichosporon species are opportunistic yeasts which can cause infections, especially in immunocompromised patients. This is a report of Trichosporon ovoides that caused subcutaneous infection in a patient with underlying ischemic heart disease. The identification of fungal isolate was confirmed by PCR sequencing of ITS and large subunit regions in rRNA gene. In vitro susceptibility study showed that the isolate was susceptible to amphotericin B, fluconazole and voriconazole, and resistant to caspofungin, anidulafungin and itraconazole. The lesion improved after treatment with oral fluconazole and topical miconazole.
  18. Murugaiah H, Teh CL, Loh KC, Mohamad Yahya AR, Md Noh NA, Abu Bakar NHH, et al.
    Molecules, 2021 Oct 24;26(21).
    PMID: 34770823 DOI: 10.3390/molecules26216414
    Here, we report the extracellular biosynthesis of silver nanoparticles (AgNPs) and determination of their antibacterial and anticancer properties. We also explore the efficacy of bioAgNPs incorporated in cellulose nanocrystals (CNCs) and alginate (Alg) for the formation of an antibacterial hydrogel film. Streptomyces sp. PBD-311B was used for the biosynthesis of AgNPs. The synthesized bioAgNPs were characterized using UV-Vis spectroscopy, TEM, XRD, and FTIR analysis. Then, the bioAgNPs' antibacterial and anticancer properties were determined using TEMA and cytotoxicity analysis. To form the antibacterial hydrogel film, bioAgNPs were mixed with a CNC and Alg solution and further characterized using FTIR analysis and a disc diffusion test. The average size of the synthesized bioAgNPs is around 69 ± 2 nm with a spherical shape. XRD analysis confirmed the formation of silver nanocrystals. FTIR analysis showed the presence of protein capping at the bioAgNP surface and could be attributed to the extracellular protein binding to bioAgNPs. The MIC value of bioAgNPs against P. aeruginosa USM-AR2 and MRSA was 6.25 mg/mL and 3.13 mg/mL, respectively. In addition, the bioAgNPs displayed cytotoxicity effects against cancer cells (DBTRG-0.5MG and MCF-7) and showed minimal effects against normal cells (SVG-p12 and MCF-10A), conferring selective toxicity. Interestingly, the bioAgNPs still exhibited inhibition activity when incorporated into CNC/Alg, which implies that the hydrogel film has antibacterial properties. It was also found that bioAgNP-CNC/Alg displayed a minimal or slow release of bioAgNPs owing to the intermolecular interaction and the hydrogel's properties. Overall, bioAgNP-CNC/Alg is a promising antibacterial hydrogel film that showed inhibition against the pathogenic bacteria P. aeruginosa and MRSA and its application can be further evaluated for the inhibition of cancer cells. It showed benefits for surgical resection of a tumor to avoid post-operative wound infection and tumor recurrence at the surgical site.
  19. Ng CYB, Gan WC, Velayutham TS, Goh BT, Hashim R
    Phys Chem Chem Phys, 2020 Jan 29;22(4):2414-2423.
    PMID: 31939468 DOI: 10.1039/c9cp01556f
    The effects of solvents and temperature on the crystal formation were investigated for vinylidene fluoride/trifluoroethylene copolymer P(VDF-TrFE). Highly crystalline P(VDF-TrFE) thin films were fabricated by spin-casting using various polar solvents such as diethyl carbonate (DEC), methyl ethyl ketone (MEK), N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Ferroelectric polarisation reversal of the P(VDF-TrFE) was evidenced by a displacement (D)-electric field (E) hysteresis loop measurement and supported by the presence of pyroelectric activity. The samples which were annealed above 100 °C gave elongated rod-like crystalline structures and the highest crystallinity, Xc of 83% was formed at 120 °C. Consequently, remnant polarisation (85 mC m-2) and the pyroelectric coefficient (30 μC m-2 K-1) were enhanced. Thus, annealing plays a substantial role in controlling the crystalline structure of P(VDF-TrFE) films regardless of the choice of solvent. Although, the crystalline structure control is almost independent of the solvent's polarity, the choice of solvent is essential in preparing a smoother film surface. Molecular dynamics of P(VDF-TrFE) are discussed from the observation of two dielectric relaxation processes, β and γ related to the segmental micro-Brownian and local modes, respectively. The complete ferroelectric polarization reversal caused a reduction in the dielectric polarization and reduced the lattice spacing of the 110/200 planes.
  20. Latif NHA, Brosse N, Ziegler-Devin I, Chrusiel L, Hashim R, Hussin MH
    Int J Biol Macromol, 2023 Dec 31;253(Pt 5):127210.
    PMID: 37797852 DOI: 10.1016/j.ijbiomac.2023.127210
    The effects of steam explosion (SE) pretreatment on the structural properties of lignin isolated from coconut husk (CH) biomass via soda pulping were investigated in this work. The isolated SE lignin was classified as dilute acid impregnation SE lignin (ASEL), water impregnation SE lignin (WSEL), and 2-naphthol impregnation SE lignin (NSEL). The various types of functional groups isolated from SE lignin were characterized and compared using a variety of complementary analyses: FTIR spectroscopy, NMR spectroscopy, GPC chromatography, HPAEC-PAD chromatography and thermal analyses. It was revealed that ASEL has the highest solid recovery with 55.89 % yield as well as the highest sugars content compared to WSEL (45.66 % yield) and NSEL (49.37 % yield). Besides, all isolated SE lignin contain a significant quantity of non-condensed G-type and S-type units but less amount of H-type units as supported by previous research. The SE lignin produced lignin with higher molecular weight (Mw ASEL: 72725 g mol-1 > Mw WSEL: 13112 g mol-1 > Mw NSEL: 6891 g mol-1) seems to influence the success of the synthesis reaction of phenolic resins. Because of the large variances in the physicochemical properties of SE lignin polymers, their structural properties were increased toward numerous alternative techniques in lignin-based applications.
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