Displaying publications 521 - 540 of 7255 in total

Abstract:
Sort:
  1. Darmawan MA, Muhammad BZ, Harahap AFP, Ramadhan MYA, Sahlan M, Haryuni, et al.
    Heliyon, 2020 Dec;6(12):e05742.
    PMID: 33364505 DOI: 10.1016/j.heliyon.2020.e05742
    Tengkawang fat (Shorea stenoptera), from an indigenous plant of the Kalimantan forest, has excellent potential as an alternative source of vegetable fat because it has a high level of fatty acids composition. Activated natural bentonite can be used as a bleaching agent to improve the quality of tengkawang fat. This research aims to reduce the acidity, peroxide number values and identify the physicochemical properties (fatty acid composition, nutrients, and thermal) of tengkawang butter. Initially, tengkawang samples from Nanga Yen and Sintang were pre-treated using the degumming process with 1% phosphoric acid and the neutralization process with a 1 M NaOH 10% w/w solution. The results show that the acidity (mg NaOH/g) of the tengkawang fat samples was reduced from 11.00 to 3.36 when using bentonite activated at 200 °C. The bentonite activated with 0.5 M HCl reduced the acidity to 3.61. The peroxide number (meq O2/kg) of the tengkawang fat samples was reduced from 9.45 to 4.84 and 3.47 by bleaching with thermal-activated and acid-activated bentonites, respectively. Peroxide value correlates with β-carotene content. The smaller of the β-carotene content, the smaller the peroxide value. The acidity, peroxide number, and iodine number values from tengkawang fat after treatment adhere to the SNI 2903: 2016 standard. The main content of fatty acids in tengkawang fat is palmitic acid, stearic acid, and oleic acid. These results show that both products are suitable for the food industry in terms of the acid and peroxide numbers. The application of this research results will assist local people in increasing the economic value of the product from tengkawang plant, which is an indigenous plant from Kalimantan.
  2. Alhassan AM, Ahmed QU
    J Pharm Bioallied Sci, 2016 Oct-Dec;8(4):265-271.
    PMID: 28216948 DOI: 10.4103/0975-7406.199342
    Averrhoa bilimbi Linn. is principally cultivated for medicinal purposes in many tropical and subtropical countries of the world. Literature survey about this plant shows that A. bilimbi is mainly used as a folk medicine in the treatment of diabetes mellitus, hypertension, and as an antimicrobial agent. The prime objective of this review is to accumulate and organize literature based on traditional claims and correlate those with current findings on the use of A. bilimbi in the management of different ailments. Through interpreting already published scientific manuscripts (1995 through 2015) retrieved from the different scientific search engines, namely Medline, PubMed, EMBASE, and Science Direct databases, published articles and reports covering traditional and scientific literature related to A. bilimbi's potential role against various ailments have been thoroughly evaluated, interpreted, and discussed. Several pharmacological studies have demonstrated the ability of this plant to act as antidiabetic, antihypertensive, thrombolytic, antimicrobial, antioxidant, hepatoprotective, and hypolipidemic agent. A. bilimbi holds great value in the complementary and alternative medicine as evidenced by the substantial amount of research on it. Therefore, we aimed to compile an up-to-date and comprehensive review of A. bilimbi that covers its traditional and folk medicine uses, phytochemistry, and pharmacology. Hence, this paper presents an up-to-date and comprehensive review of the ethnomedicinal uses, different chemical constituents, and pharmacological activities of A. bilimbi. So far, the biologically active agents have not been isolated from this plant and this can be a good scientific study for the future antidiabetic, antihypertensive, and antimicrobial implications. Hence, this review targets at emphasizing the diverse traditional claims and pharmacological activities of A. bilimbi with respect to carrying out more scientific studies to isolate active principles through advanced technology.
  3. Zhi LL, Zaini MA
    Water Sci Technol, 2017 02;75(3-4):864-880.
    PMID: 28234287 DOI: 10.2166/wst.2016.568
    This work was aimed to evaluate the feasibility of castor bean residue based activated carbons prepared through metals chloride activation. The activated carbons were characterized for textural properties and surface chemistry, and the adsorption data of rhodamine B were established to investigate the removal performance. Zinc chloride-activated carbon with specific surface area of 395 m(2)/g displayed a higher adsorption capacity of 175 mg/g. Magnesium chloride and iron(III) chloride are less toxic and promising agents for composite chemical activation. The adsorption data obeyed Langmuir isotherm and pseudo-second-order kinetics model. The rate-limiting step in the adsorption of rhodamine B is film diffusion. The positive values of enthalpy and entropy indicate that the adsorption is endothermic and spontaneous at high temperature.
  4. Rahman MT, Karim MM
    Biol Trace Elem Res, 2018 Mar;182(1):1-13.
    PMID: 28585004 DOI: 10.1007/s12011-017-1061-8
    Nutritional immunity describes mechanisms for withholding essential transition metals as well as directing the toxicity of these metals against infectious agents. Zinc is one of these transition elements that are essential for both humans and microbial pathogens. At the same time, Zn can be toxic both for man and microbes if its concentration is higher than the tolerance limit. Therefore a "delicate" balance of Zn must be maintained to keep the immune cells surveilling while making the level of Zn either to starve or to intoxicate the pathogens. On the other hand, the invading pathogens will exploit the host Zn pool for its survival and replication. Apparently, different sets of protein in human and bacteria are involved to maintain their Zn need. Metallothionein (MT)-a group of low molecular weight proteins, is well known for its Zn-binding ability and is expected to play an important role in that Zn balance at the time of active infection. However, the differences in structural, functional, and molecular control of biosynthesis between human and bacterial MT might play an important role to determine the proper use of Zn and the winning side. The current review explains the possible involvement of human and bacterial MT at the time of infection to control and exploit Zn for their need.
  5. Abdul Latif R, Idrus MF
    MyJurnal DOI: 10.37134/jsspj.vol9.2.1.2020
    Music can give influence on a lot of thing. It was known as one of the sources for entertainment. It has been classified to regulate emotion, grab attention, for lift the spirit and increased work output. Nowadays, people love listening to music believed that it entertains them and thus helps to motivate the person to continue the activity. The aim of this study was to determine the differences music tempo towards emotion among gym users in UiTM Seremban 3. Sixty participants, which were gym users that attended to the gym in UiTM Seremban 3. Subjects were randomly assigned into three different groups (n=20 in each). Group 1 fast tempo (>120 bpm), group2 slow tempo (
  6. Nizar MAM, Nabil S
    Case Rep Dent, 2021;2021:5001266.
    PMID: 34394997 DOI: 10.1155/2021/5001266
    Subcutaneous emphysema (SE) is a swelling which develops due to air entrapped underneath the subcutaneous tissue and facial planes causing distention of the overlying skin. SE can develop due to trauma, surgery, or infection. The diagnosis of SE is mostly based on clinical findings of crepitation upon palpation of the swelling. Once diagnosed, SE is usually managed by close observation and in some cases may require surgical decompression and antibiotic prophylaxis. We report a rare case of SE of the left malar which developed following closure of oroantral communication using the buccal fat pad.
  7. Mohd Idris MN, Hashim H
    J Environ Manage, 2021 Oct 15;296:113118.
    PMID: 34216903 DOI: 10.1016/j.jenvman.2021.113118
    Biomass co-firing with coal can be adopted in the electricity sector to promote greenhouse gas reduction, renewable energy production, and resource efficiency improvement toward environmental sustainability. This realization, however, requires effective management of supply chain issues, such as the collection of biomass feedstock, the transportation of biomass, and the localization of biomass processing plants to deliver the co-firing scales needed. This work addresses these issues by providing a techno-economic assessment conducted in a spatially-explicit manner to investigate the opportunity for scaling up the co-firing deployment at the national scale. The modeling approach is applied to the case of Malaysia's coal and palm oil biomass industries. The number of cases involving the impact of energy decarbonization targets, economic policy instrument, and supply chain cost parameter variations on the co-firing scales deployed are assessed. The findings show that densified biomass feedstock can substitute significant shares of coal capacities to deliver up to 29 MtCO2/year of carbon dioxide reduction. Nevertheless, this would cause a surge in the electricity system cost by up to 2 billion USD/year due to the substitution of up to 40% of the coal plant capacities. In facilitating the maximal deployment of co-firing at the national scale, more than 100 solid biofuel production plants would need to be built to support a maximum of 41 TWh/year of co-firing capacity. Actions to minimize the specific cost elements of the biomass co-firing supply chain are thus needed in the near term to increase the effectiveness of economic policy instrument to promote co-firing and reduce environmental emissions.
  8. Arumugam M, Tahir M, Praserthdam P
    Chemosphere, 2022 Jan;286(Pt 2):131765.
    PMID: 34371351 DOI: 10.1016/j.chemosphere.2021.131765
    Photocatalytic conversion of carbon dioxide (CO2) into gaseous hydrocarbon fuels is an auspicious way to produce renewable fuels in addition to greenhouse gas emission mitigation. In this work, non-metals (B, O, P, and S) doped graphitic carbon nitride (g-C3N4) was prepared via solid-state polycondensation of urea for photocatalytic CO2 reduction into highly needed methane (CH4) with water under UV light irradiation. The various physicochemical characterization results reveal the successful incorporation of B, O, P, and S elements in the g-C3N4 matrix. The maximum CH4 yield of 55.10 nmol/(mLH2O.gcat) over S-doped g-C3N4 has been obtained for CO2 reduction after 7 h of irradiation. This amount of CH4 production was 1.9, 1.4, 1.7, and 2.4-folds higher than B, O, P and bare g-C3N4 samples. The doping of S did not enlarge the surface area and photon absorption ability of the g-C3N4 sample, but this significant improvement was evidently due to effective charge separation and migration. The observed results imply that the doping of non-metal elements provides improved charge separation and is an effective way to boost photocatalyst performance. This work offers an auspicious approach to design non-metal doped g-C3N4 photocatalysts for renewable fuel production and would be promising for other energy application.
  9. Aabideen ZU, Mumtaz MW, Akhtar MT, Raza MA, Mukhtar H, Irfan A, et al.
    Plants (Basel), 2021 Jun 29;10(7).
    PMID: 34210016 DOI: 10.3390/plants10071334
    The present work was aimed at investigating hydroethanolic leaf extracts of Cassia fistula for their antioxidant and pancreatic lipase (PL) enzyme inhibitory properties. The most active extract was selected to profile the phytoconstituents by UHPLC-QTOF-MS/MS technique. Among the tested extracts, the 80% hydroethanolic extract exhibited the maximum levels of total phenolic and flavonoid contents (TPC and TFC) with a contribution of 201.3 ± 2.6 mg of gallic acid equivalent per gram of extract (GAE/g extract), and 116.3 ± 2.4 mg of rutin equivalent per gram of extract (RE/g extract), respectively. The same extract also showed promising 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and PL inhibitory activity with an IC50 (half maximal inhibitory concentration) of 30.5 ± 2.8 µg/mL and 17.31 ± 1.18 μg/mL, respectively. The phytochemical profiling of 80% hydroethanolic extract confirmed the presence of 23 metabolites of immense medicinal significance. Docking studies were conducted to investigate the potential interactions of compounds identified in the study. The docking study-based binding energy data and the interaction scheme both revealed the possible role of the identified compounds towards PL inhibitor. Moreover, energies of frontier molecular orbitals (FMOs), ionization potentials (IP), electron affinities (EA) and molecular electrostatic potentials (MEP) were also explored. The findings of the current work suggest that C. fistula is a promising natural source of antioxidant and antiobesity agents, which may be exploited to add pharmacological functionalities to food.
  10. Isleem HF, Abid M, Alaloul WS, Shah MK, Zeb S, Musarat MA, et al.
    Materials (Basel), 2021 Jun 23;14(13).
    PMID: 34201659 DOI: 10.3390/ma14133498
    The majority of experimental and analytical studies on fiber-reinforced polymer (FRP) confined concrete has largely concentrated on plain (unreinforced) small-scale concrete columns, on which the efficiency of strengthening is much higher compared with large-scale columns. Although reinforced concrete (RC) columns subjected to combined axial compression and flexural loads (i.e., eccentric compression) are the most common structural elements used in practice, research on eccentrically-loaded FRP-confined rectangular RC columns has been much more limited. More specifically, the limited research has generally been concerned with small-scale RC columns, and hence, the proposed eccentric-loading stress-strain models were mainly based on the existing concentric-loading models of FRP-confined concrete columns of small scale. In the light of such demand to date, this paper is aimed at developing a mathematical model to better predict the strength of FRP-confined rectangular RC columns. The strain distribution of FRP around the circumference of the rectangular sections was investigated to propose equations for the actual rupture strain of FRP wrapped in the horizontal and vertical directions. The model was accomplished using 230 results of 155 tested specimens compiled from 19 studies available in the technical literature. The test database covers an unconfined concrete strength ranging between 9.9 and 73.1 MPa, and section's dimension ranging from 100-300 mm and 125-435 mm for the short and long sides, respectively. Other test parameters, such as aspect ratio, corner radius, internal hoop steel reinforcement, FRP wrapping layout, and number of FRP wraps were all considered in the model. The performance of the model shows a very good correlation with the test results.
  11. Rendana M, Idris WMR
    J Infect Public Health, 2021 Oct;14(10):1320-1327.
    PMID: 34175236 DOI: 10.1016/j.jiph.2021.05.019
    BACKGROUND: World Health Organization has reported fifty countries have now detected the new coronavirus (B.1.1.7 variant) since a couple of months ago. In Indonesia, the B.1.1.7 cases have been found in several provinces since January 2021, although they are still in a lower number than the old variant of COVID-19. Therefore, this study aims to create a forecast analysis regarding the occasions of COVID-19 and B.1.1.7 cases based on data from the 1st January to 18th March 2021, and also analyze the association between meteorological factors with B.1.1.7 incidences in three different provinces of Indonesia such as the West Java, South Sumatra and East Kalimantan.

    METHODS: We used the Autoregressive Moving Average Models (ARIMA) to forecast the number of cases in the upcoming 14 days and the Spearman correlation analysis to analyze the relationship between B.1.1.7 cases and meteorological variables such as temperature, humidity, rainfall, sunshine, and wind speed.

    RESULTS: The results of the study showed the fitted ARIMA models forecasted there was an increase in the daily cases in three provinces. The total cases in three provinces would increase by 36% (West Java), 13.5% (South Sumatra), and 30% (East Kalimantan) as compared with actual cases until the end of 14 days later. The temperature, rainfall and sunshine factors were the main contributors for B.1.1.7 cases with each correlation coefficients; r = -0.230; p < 0.05, r = 0.211; p < 0.05 and r = -0.418; p < 0.01, respectively.

    CONCLUSIONS: We recapitulated that this investigation was the first preliminary study to analyze a short-term forecast regarding COVID-19 and B.1.1.7 cases as well as to determine the associated meteorological factors that become primary contributors to the virus spread.

  12. Masseran N, Safari MAM
    PMID: 34201763 DOI: 10.3390/ijerph18136754
    This article proposes a novel data selection technique called the mixed peak-over-threshold-block-maxima (POT-BM) approach for modeling unhealthy air pollution events. The POT technique is employed to obtain a group of blocks containing data points satisfying extreme-event criteria that are greater than a particular threshold u. The selected groups are defined as POT blocks. In parallel with that, a declustering technique is used to overcome the problem of dependency behaviors that occurs among adjacent POT blocks. Finally, the BM concept is integrated to determine the maximum data points for each POT block. Results show that the extreme data points determined by the mixed POT-BM approach satisfy the independent properties of extreme events, with satisfactory fitted model precision results. Overall, this study concludes that the mixed POT-BM approach provides a balanced tradeoff between bias and variance in the statistical modeling of extreme-value events. A case study was conducted by modeling an extreme event based on unhealthy air pollution events with a threshold u > 100 in Klang, Malaysia.
  13. Maisarah Mansor, Afiqah Mohd Nawi, Nadiah Husseini Zainol Abidin, Muhammad Firdaus Omar, Mohd Adzir Mahdi, Muhammad Hafiz Abu Bakar
    MyJurnal
    This work demonstrates the tunability of tapered single mode fiber (SMF) and tapered polarization maintaining fiber (PMF) filters based on fiber twisting method. One end of the tapered fiber was twisted from 0o until 100o using the Vytran Fiber Processing System. Observation on the spectral output shows that the fiber twisting technique is a viable option to impart tunability in tapered fibers with total shift of 15 and 10 nm, respectively for SMF and PMF. Better tunability is observed in the SMF filter due to its simple physical structure and more straightforward interferometry effect but a significantly higher extinction ratio is observed for the PMF filter. Both filters exhibited region of linear wavelength shift with corresponding R2 values of 0.9924 and 0.9294 for SMF and PMF. The simplicity and reliability of the filter may pave the way for the development of a practical and compact tunable all-fiber filter for laser systems.
  14. Iqbal MO, Yahya EB
    Tissue Cell, 2021 Oct;72:101525.
    PMID: 33780659 DOI: 10.1016/j.tice.2021.101525
    Aminoglycoside antibiotics are widely employed clinically due to their powerful bactericidal activities, less bacterial resistance compared to beta lactam group and low cost. However, their use has been limited in recent years due to their potential induction of nephrotoxicity. Here we investigate the possibility of reversing nephrotoxicity caused by gentamicin in rat models by using ethanolic crude extract of the medicinal plant Jatropha Mollissima. Nephrotoxic male Wistar rats was obtained by gentamicin antibiotic, which then treated with two doses of J. mollissima crude extract for 3 weeks with monitoring their parameter in weekly base. Our results indicate that J. mollissima crude extract at both doses has strong protection ability against gentamicin nephrotoxicity, most of tested parameters backed to normal values after few days from the administration of the crude extract, which could be due to the antagonized the biochemical action of gentamicin on the proximal tubules of the kidney. The results of histopathologic analysis showed observable improvement in J. mollissima treated groups compared with untreated groups. Our findings suggests the J. mollissima has exceptional nephron protection potentials able to reverse the nephrotoxicity caused by gentamicin antibiotic.
  15. Abdul Majid MH, Ibrahim K
    PLoS One, 2021;16(9):e0257762.
    PMID: 34555115 DOI: 10.1371/journal.pone.0257762
    In data modelling using the composite Pareto distribution, any observations above a particular threshold value are assumed to follow Pareto type distribution, whereas the rest of the observations are assumed to follow a different distribution. This paper proposes on the use of Bayesian approach to the composite Pareto models involving specification of the prior distribution on the proportion of data coming from the Pareto distribution, instead of assuming the prior distribution on the threshold, as often done in the literature. Based on a simulation study, it is found that the parameter estimates determined when using uniform prior on the proportion is less biased as compared to the point estimates determined when using uniform prior on the threshold. Applications on income data and finance are included for illustrative examples.
  16. Yazid MD, Hung-Chih C
    Cell Commun Signal, 2021 10 27;19(1):105.
    PMID: 34706731 DOI: 10.1186/s12964-021-00785-0
    BACKGROUND: The absence of dystrophin has gave a massive impact on myotube development in Muscular Dystrophy pathogenesis. One of the conserved signaling pathways involved in skeletal muscle differentiation is the PI3K/Akt/mTOR pathway that plays a vital role in autophagy regulation. To further understand and establish targeted therapy in dystrophin-deficient myoblasts, protein expression profiling has been determined which provides information on perturbed autophagy modulation and activation.

    METHODS: In this study, a dystrophin-deficient myoblast cell line established from the skeletal muscle of a dystrophic (mdx) mouse was used as a model. The dfd13 (dystrophin-deficient) and C2C12 (non-dystrophic) myoblasts were cultured in low mitogen conditions for 10 days to induce differentiation. The cells were subjected to total protein extraction prior to Western blotting assay technique. Protein sub-fractionation has been conducted to determine protein localization. The live-cell analysis of autophagy assay was done using a flow cytometer.

    RESULTS: In our culture system, the dfd13 myoblasts did not achieve terminal differentiation. PTEN expression was profoundly increased in dfd13 myoblasts throughout the differentiation day subsequently indicates perturbation of PI3K/Akt/mTOR regulation. In addition, rictor-mTORC2 was also found inactivated in this event. This occurrence has caused FoxO3 misregulation leads to higher activation of autophagy-related genes in dfd13 myoblasts. Autophagosome formation was increased as LC3B-I/II showed accumulation upon differentiation. However, the ratio of LC3B lipidation and autophagic flux were shown decreased which exhibited dystrophic features.

    CONCLUSION: Perturbation of the PTEN-PI3K/Akt pathway triggers excessive autophagosome formation and subsequently reduced autophagic flux within dystrophin-deficient myoblasts where these findings are of importance to understand Duchenne Muscular Dystrophy (DMD) patients. We believe that some manipulation within its regulatory signaling reported in this study could help restore muscle homeostasis and attenuate disease progression. Video Abstract.

  17. Amran MS, Jamaludin KA
    Front Public Health, 2021;9:639041.
    PMID: 34164364 DOI: 10.3389/fpubh.2021.639041
    School closures were implemented as a public health intervention to reduce the risk of infection from COVID-19. However, prolonged school closure is likely to impact adolescents' behavioral health due to the extreme change in routine. The current study aimed to explore adolescents' behavioral health experiences during the beginning of the outbreak of the COVID-19 pandemic. This study was done using qualitative methods to interview 15 adolescent participants (n =15) from low-income households in Malaysia. The study lasted for 2 months amidst the outbreak and data were collected via online based on focus group discussions. The results revealed that adolescents faced four main themes of experience during the COVID-19 pandemic: Alteration of sleep patterns, stress-related fatigue, dysfunctional eating patterns and lack of physical activity. This first-hand experience shows that knowledge and skills of adolescents' behavioral practices during outbreak deserves attention. This research stresses the role of family, schools, and media in addressing the health communication gap among adolescents to help them adapt in these new norms.
  18. Nasaruddin ML, Tajul Arifin K
    J Fungi (Basel), 2021 Nov 19;7(11).
    PMID: 34829274 DOI: 10.3390/jof7110987
    This scoping review is aimed at the application of the metabolomics platform to dissect key metabolites and their intermediates to observe the regulatory mechanisms of starvation-induced autophagy in Saccharomyces cerevisiae. Four research papers were shortlisted in this review following the inclusion and exclusion criteria. We observed a commonly shared pathway undertaken by S. cerevisiae under nutritional stress. Targeted and untargeted metabolomics was applied in either of these studies using varying platforms resulting in the annotation of several different observable metabolites. We saw a commonly shared pathway undertaken by S. cerevisiae under nutritional stress. Following nitrogen starvation, the concentration of cellular nucleosides was altered as a result of autophagic RNA degradation. Additionally, it is also found that autophagy replenishes amino acid pools to sustain macromolecule synthesis. Furthermore, in glucose starvation, nucleosides were broken down into carbonaceous metabolites that are being funneled into the non-oxidative pentose phosphate pathway. The ribose salvage allows for the survival of starved yeast. Moreover, acute glucose starvation showed autophagy to be involved in maintaining ATP/energy levels. We highlighted the practicality of metabolomics as a tool to better understand the underlying mechanisms involved to maintain homeostasis by recycling degradative products to ensure the survival of S. cerevisiae under starvation. The application of metabolomics has extended the scope of autophagy and provided newer intervention targets against cancer as well as neurodegenerative diseases in which autophagy is implicated.
  19. Khairuddin MAN, Lasekan O
    Foods, 2021 Oct 21;10(11).
    PMID: 34828804 DOI: 10.3390/foods10112523
    In the past decades, food products and beverages made from gluten-free cereals were initially created for certain groups of people who experience gluten-related disorders such as wheat allergies, gluten ataxia, non-celiac gluten sensitivity, and the most well-known, celiac disease. Nowadays, the consumption of gluten-free products is not only restricted to targeted groups, but it has become a food trend for normal consumers, especially in countries such as the UK, the US, and some European countries, who believe that consuming a gluten-free product is a healthier choice compared to normal gluten-containing products. However, some research studies have disapproved of this claim because the currently available gluten-free products in the market are generally known to be lower in proteins, vitamins, and minerals and to contain higher lipids, sugar, and salt compared to their gluten-containing counterparts. The use of other gluten-free cereals such as sorghum, millet, and teff as well as pseudo cereals such as buckwheat and quinoa has gained significant interest in research in terms of their various potential health benefits. Hence, this review highlights the potential health benefits of some gluten-free cereals and pseudo cereals apart from corn and rice in the last decade. The potential health benefits of gluten-free products such as bread, pasta, crackers, and cookies and the health benefits of some other non-alcoholic beverages made from gluten-free cereals and pseudo cereals are reported.
  20. Naz S, Uroos M, Ayoub M
    ACS Omega, 2021 Nov 02;6(43):29233-29242.
    PMID: 34746611 DOI: 10.1021/acsomega.1c04881
    This work presents a cost-effective approach for processing of renewable carbon-rich biomass using pyridinium-based Lewis acidic ionic liquids (LAILs). Rice husk as carbon-rich lignocellulosic waste was pretreated with a series of neutral and Lewis acidic ionic liquids to yield valuable intermediate platform monosaccharides. Novelty in the work lies in direct conversion of lignocellulosic carbohydrates into reducing sugars without their further conversion into 5-hydroxymethylfurfural or any other platform chemicals that are fermentation inhibitors for bioethanol production. The unconverted cellulose-rich material (CRM) is regenerated as a delignified material by the simultaneous addition of antisolvents. CRM and recovered lignin obtained after pretreatment were analyzed via scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier transform infrared (FTIR) spectroscopy. The process was optimized with respect to a high yield of platform sugars and the quantity as well as quality of recovered CRM and lignin contents. Various reaction parameters involving the molecular structure of ionic liquids (ILs), Lewis acidic strength of ILs, biomass loading into IL, time, temperature, and biomass particle size were screened thoroughly. From all of the tested ILs, unsymmetrical 3-methylpyridinium IL having N-octyl substitution and chloroaluminate anion showed a greater conversion efficiency at 100 °C for 1.5 h. FTIR and SEM analyses of recovered CRM justify >90% lignin removal from rice husk. From all of the removed lignin, 60 wt % of original lignin content was recovered. The Lewis acidic system possessed recycling ability up to 3 times for subsequent treatment of rice husk without a significant loss of efficiency.
Filters
Contact Us

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

External Links