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  1. Fulltext Patterned Array of Poly(ethylene glycol) Silane Monolayer for Label-Free Detection of Dengue
    Rosly NZ, Ahmad SA, Abdullah J, Yusof NA
    Sensors (Basel), 2016 Aug 25;16(9).
    PMID: 27571080 DOI: 10.3390/s16091365
    In the present study, the construction of arrays on silicon for naked-eye detection of DNA dengue was demonstrated. The array was created by exposing a polyethylene glycol (PEG) silane monolayer to 254 nm ultraviolet (UV) light through a photomask. Formation of the PEG silane monolayer and photomodifed surface properties was thoroughly characterized by using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and contact angle measurements. The results of XPS confirmed that irradiation of ultraviolet (UV) light generates an aldehyde functional group that offers conjugation sites of amino DNA probe for detection of a specific dengue virus target DNA. Employing a gold enhancement process after inducing the electrostatic interaction between positively charged gold nanoparticles and the negatively charged target DNA hybridized to the DNA capture probe allowed to visualize the array with naked eye. The developed arrays demonstrated excellent performance in diagnosis of dengue with a detection limit as low as 10 pM. The selectivity of DNA arrays was also examined using a single base mismatch and noncomplementary target DNA.
    Matched MeSH terms: Cetrimonium Compounds/chemistry; Gold/chemistry; Polyethylene Glycols/chemistry*; Silanes/chemistry*; Metal Nanoparticles/chemistry
  2. Sono-assisted TEMPO oxidation of oil palm lignocellulosic biomass for isolation of nanocrystalline cellulose
    Rohaizu R, Wanrosli WD
    Ultrason Sonochem, 2017 01;34:631-639.
    PMID: 27773290 DOI: 10.1016/j.ultsonch.2016.06.040
    Highly stable and dispersible nanocrystalline cellulose (NCC) was successfully isolated from oil palm empty fruit bunch microcrystalline cellulose (OPEFB-MCC), with yields of 93% via a sono-assisted TEMPO-oxidation and a subsequent sonication process. The sono-assisted treatment has a remarkable effect, resulting in an increase of more than 100% in the carboxylate content and a significant increase of approximately 39% in yield compared with the non-assisted process. TEM images reveal the OPEFB-NCC to have rod-like crystalline morphology with an average length and width of 122 and 6nm, respectively. FTIR and solid-state 13C-NMR analyses suggest that oxidation of cellulose chain hydroxyl groups occurs at C6. XRD analysis shows that OPEFB-NCC consists primarily of a crystalline cellulose I structure. Both XRD and 13C-NMR indicate that the OPEFB-NCC has a lower crystallinity than the OPEFB-MCC starting material. Thermogravimetric analysis illustrates that OPEFB-NCC is less thermally stable than OPEFB-MCC but has a char content of 46% compared with 7% for the latter, which signifies that the carboxylate functionality acts as a flame retardant.
    Matched MeSH terms: Cellulose/chemistry; Cyclic N-Oxides/chemistry*; Lignin/chemistry*; Arecaceae/chemistry*; Nanoparticles/chemistry*
  3. Modified porous scaffolds of silk fibroin with mimicked microenvironment based on decellularized pulp/fibronectin for designed performance biomaterials in maxillofacial bone defect
    Sangkert S, Kamonmattayakul S, Chai WL, Meesane J
    J Biomed Mater Res A, 2017 Jun;105(6):1624-1636.
    PMID: 28000362 DOI: 10.1002/jbm.a.35983
    Maxillofacial bone defect is a critical problem for many patients. In severe cases, the patients need an operation using a biomaterial replacement. Therefore, to design performance biomaterials is a challenge for materials scientists and maxillofacial surgeons. In this research, porous silk fibroin scaffolds with mimicked microenvironment based on decellularized pulp and fibronectin were created as for bone regeneration. Silk fibroin scaffolds were fabricated by freeze-drying before modification with three different components: decellularized pulp, fibronectin, and decellularized pulp/fibronectin. The morphologies of the modified scaffolds were observed by scanning electron microscopy. Existence of the modifying components in the scaffolds was proved by the increase in weights and from the pore size measurements of the scaffolds. The modified scaffolds were seeded with MG-63 osteoblasts and cultured. Testing of the biofunctionalities included cell viability, cell proliferation, calcium content, alkaline phosphatase activity (ALP), mineralization and histological analysis. The results demonstrated that the modifying components organized themselves into aggregations of a globular structure. They were arranged themselves into clusters of aggregations with a fibril structure in the porous walls of the scaffolds. The results showed that modified scaffolds with a mimicked microenvironment of decellularized pulp/fibronectin were suitable for cell viability since the cells could attach and spread into most of the pores of the scaffold. Furthermore, the scaffolds could induce calcium synthesis, mineralization, and ALP activity. The results indicated that modified silk fibroin scaffolds with a mimicked microenvironment of decellularized pulp/fibronectin hold promise for use in tissue engineering in maxillofacial bone defects. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1624-1636, 2017.
    Matched MeSH terms: Dental Pulp/chemistry*; Fibroins/chemistry*; Fibronectins/chemistry*; Bone Substitutes/chemistry*; Tissue Scaffolds/chemistry*
  4. Human Milk Fat Globule Membrane Contains Hundreds of Abundantly Expressed and Nutritionally Beneficial Proteins That Are Generally Lacking in Caprine Milk
    Juvarajah T, Wan-Ibrahim WI, Ashrafzadeh A, Othman S, Hashim OH, Fung SY, et al.
    Breastfeed Med, 2018 11;13(9):631-637.
    PMID: 30362820 DOI: 10.1089/bfm.2018.0057
    BACKGROUND: Bioactive proteins from milk fat globule membrane (MFGM) play extensive roles in cellular processes and defense mechanisms in infants. The aims of this study were to identify differences in protein compositions in human and caprine MFGM using proteomics and evaluate possible nutritional benefits of caprine milk toward an infant's growth, as an alternative when breastfeeding or human milk administration is not possible or inadequate.

    MATERIALS AND METHODS: Human and caprine MFGM proteins were isolated and analyzed, initially by polyacrylamide gel electrophoresis, and subsequently by quadrupole time-of-flight liquid chromatography-mass spectrometry. This was then followed by database search and gene ontology analysis. In general, this method selectively analyzed the abundantly expressed proteins in milk MFGM.

    RESULTS: Human MFGM contains relatively more abundant bioactive proteins compared with caprine. While a total of 128 abundant proteins were detected in the human MFGM, only 42 were found in that of the caprine. Seven of the bioactive proteins were apparently found to coexist in both human and caprine MFGM.

    RESULTS/DISCUSSION: Among the commonly detected MFGM proteins, lactotransferrin, beta-casein, lipoprotein lipase, fatty acid synthase, and butyrophilin subfamily 1 member A1 were highly expressed in human MFGM. On the other hand, alpha-S1-casein and EGF factor 8 protein, which are also nutritionally beneficial, were found in abundance in caprine MFGM. The large number of human MFGM abundant proteins that were generally lacking in caprine appeared to mainly support human metabolic and developmental processes.

    CONCLUSION: Our data demonstrated superiority of human MFGM by having more than one hundred nutritionally beneficial and abundantly expressed proteins, which are clearly lacking in caprine MFGM. The minor similarity in the abundantly expressed bioactive proteins in caprine MFGM, which was detected further, suggests that it is still nutritionally beneficial, and therefore should be included when caprine milk-based formula is used as an alternative.

    Matched MeSH terms: Glycolipids/chemistry*; Glycoproteins/chemistry*; Milk/chemistry*; Milk Proteins/chemistry*; Milk, Human/chemistry*
  5. Isolation of antioxidative compounds from Micromelum minutum guided by preparative thin layer chromatography-2,2-diphenyl-1-picrylhydrazyl (PTLC-DPPH) bioautography method
    Kassim NK, Lim PC, Ismail A, Awang K
    Food Chem, 2019 Jan 30;272:185-191.
    PMID: 30309531 DOI: 10.1016/j.foodchem.2018.08.045
    The application of preparative thin layer chromatography-2,2-diphenyl-1-picrylhydrazyl (PTLC-DPPH) bioautography technique successfully isolated a lignan sesamin (1), two prenylated coumarins (2 and 3) and a marmesin glycosides (4) from Micromelum minutum methanol bark extract. Compounds 2 and 3 were identified as new compounds whereas 1 and 4 were first isolated from Micromelum genus. Structural identification of all compounds were done by detailed spectroscopic analyses and comparison with literature data. Antioxidant capacities of extract, active fraction and compounds were measured based on DPPH free radical savenging activity, oxygen radical absorbance capacity (ORAC) and β-carotene bleaching. The DPPH activity of methanol extract and its fraction present the IC50 values of 54.3 and 168.9 µg/mL meanwhile the β-carotene bleaching results were 55.19% and 5.75% respectively. The ORAC measurements of M. minutum extract, compounds 2 and 4 showed potent antioxidant activity with the values of 5123, 5539 and 4031 µmol TE/g respectively.
    Matched MeSH terms: Antioxidants/chemistry; Biphenyl Compounds/chemistry*; Picrates/chemistry*; Plant Extracts/chemistry; Rutaceae/chemistry*
  6. Hydrodynamic cavitation assisted degradation of persistent endocrine-disrupting organochlorine pesticide Dicofol: Optimization of operating parameters and investigations on the mechanism of intensification
    Panda D, Manickam S
    Ultrason Sonochem, 2019 Mar;51:526-532.
    PMID: 30224289 DOI: 10.1016/j.ultsonch.2018.04.003
    Dicofol, a recommended Stockholm convention persistent organic pollutants (POPs) candidate is well known for its endocrine disruptive properties and has been extensively used as an organochlorine pesticide worldwide. The hydrodynamic cavitation (HC) treatment of Dicofol in aqueous media induced by a liquid whistle hydrodynamic cavitaion reactor (LWHCR) has been investigated while considering important parameters such as inlet pressure, initial concentration of Dicofol, solution temperature, pH, addition of H2O2 and radical scavenger for the extent of degradation. The pseudo-first-order degradation rate constant (k) was determined to be 0.073 min-1 with a cavitational yield of 1.26 × 10-5 mg/J at optimum operating conditions and a complete removal of Dicofol was achieved within 1 h of treatment. Considering the removal rate and energy efficiency, the optimal inlet pressure was found to be 7 bar, resulting in a cavitation number of 0.17. High performance liquid chromatography (HPLC) and Gas chromatography mass spectroscopy (GC-MS) analyses indicated a sharp decline in the concentration of Dicofol with treatment time and indicated the presence of degraded products. An 85% total organic carbon (TOC) removal was achieved within 1 h of treatment time, demonstrating successful mineralization of Dicofol. The obtained results suggest that the degradation of Dicofol followed thermal decomposition and successive recombination reactions at bubble-vapor interface. Overall, the attempted hydrodynamic cavitation demonstrated successful and rapid removal of endocrine disruptive chemicals such as Dicofol and is expected to provide efficient solution for wastewater treatment.
    Matched MeSH terms: Dicofol/chemistry*; Hydrogen Peroxide/chemistry; Pesticide Residues/chemistry*; Free Radical Scavengers/chemistry; Endocrine Disruptors/chemistry*
  7. Effect of cogon grass fibre on the thermal, mechanical and biodegradation properties of thermoplastic cassava starch biocomposite
    Jumaidin R, Khiruddin MAA, Asyul Sutan Saidi Z, Salit MS, Ilyas RA
    Int J Biol Macromol, 2020 Mar 01;146:746-755.
    PMID: 31730973 DOI: 10.1016/j.ijbiomac.2019.11.011
    Thermoplastic cassava starch (TPCS) is a promising alternative material to replace the non-biodegradable petroleum based polymer due to its good environmental-friendly aspect i.e. abundant, sustainable, recyclable and biodegradable in nature. However, TPCS have some limitation such as poor mechanical properties. Therefore, in the present study, cogon grass fibre (CGF) were incorporated into TPCS using compression molding. Then the fundamental properties of CFG/TPCS biopolymer composites were carried out in order to evaluate their potential as a biodegradable reinforcement. From the study it was found that, the incorporation of CFG has improved the tensile and flexural properties of the TPCS composites, while the impact strength and elongation were reduced. The thermal properties of the biocomposite were reduced as the cogon grass fibres increase from 0 to 5%. In term of morphological, SEM shows good fibre adhesion between CGF and TPCS. Soil burial test shows that incorporation of CGF into TPCS has slow down the biodegradation process of the composites. Thus, CGF/TPCS biopolymer composites can be classified as composites with great potential as environmental-friendly material that biodegradable and renewable.
    Matched MeSH terms: Manihot/chemistry*; Composite Resins/chemistry*; Poaceae/chemistry*; Polymers/chemistry; Starch/chemistry
  8. Emerging frontiers of deep eutectic solvents in drug discovery and drug delivery systems
    Zainal-Abidin MH, Hayyan M, Ngoh GC, Wong WF, Looi CY
    J Control Release, 2019 12 28;316:168-195.
    PMID: 31669211 DOI: 10.1016/j.jconrel.2019.09.019
    The applications of eutectic systems, including deep eutectic solvents (DESs), in diverse sectors have drawn significant interest from researchers, academicians, engineers, medical scientists, and pharmacists. Eutecticity increases drug dissolution, improves drug penetration, and acts as a synthesis route for drug carriers. To date, DESs have been extensively explored as potential drug delivery systems on account of their unique properties such as tunability and chemical and thermal stability. This review discusses two major topics: first, the application of eutectic mixtures (before and after the introduction of DES) in the field of drug delivery systems, and second, the most promising examples of DES pharmaceutical activity. It also considers future prospects in the medical and biotechnological fields. In addition to the application of DESs in drug delivery systems, they show greatly promising pharmaceutical activities, including anti-fungal, anti-bacterial, anti-viral, and anti-cancer activities. Eutecticity is a valid strategy for overcoming many obstacles inherently associated with either introducing new drugs or enhancing drug delivery systems.
    Matched MeSH terms: Chemistry, Pharmaceutical/methods; Drug Carriers/chemistry; Pharmaceutical Preparations/chemistry; Solvents/chemistry*
  9. Fulltext Adsorption of Rhodamine B dye from aqueous solution onto acid treated banana peel: Response surface methodology, kinetics and isotherm studies
    Oyekanmi AA, Ahmad A, Hossain K, Rafatullah M
    PLoS One, 2019;14(5):e0216878.
    PMID: 31091269 DOI: 10.1371/journal.pone.0216878
    The adsorption of rhodamine B (RhB) using acid modified banana peels has been examined. Chemical characteristics of the adsorbents were observed in order to determine active functional groups. The major functional groups on the surface were OH, C = O, C = C and C-O-C. Interactions between operational parameters were studied using the central composite design (CCD) of response surface methodology (RSM). The predictions of the model output indicated that operational factors influenced responses at a confidence level of 95% (P<0.05). The optimum conditions for adsorption were pH 2 at a 0.2 g/L dose within 60 minutes of contact time. Isotherm studies were carried out using the optimized process variables. The data revealed that RhB adsorption fitted the Langmuir isotherm equation while the reduction of COD followed the Freundlich isotherm. Kinetic experiments fitted the pseudo second order model for RhB removal and COD reduction. The adsorption mechanism was not the only rate controlling step. Diffusion through the boundary layer described the pattern of adsorption.
    Matched MeSH terms: Coloring Agents/chemistry*; Fruit/chemistry*; Rhodamines/chemistry*; Water Pollutants, Chemical/chemistry*; Musa/chemistry*
  10. Identification of Novel Sesamol Dimers with Unusual Methylenedioxy Ring-Opening Skeleton and Evaluation of Their Antioxidant and Cytotoxic Activities
    Murthy S, Hazli UHAM, Kong KW, Mai CW, Leong CO, Rahman NA, et al.
    Curr Org Synth, 2019;16(8):1166-1173.
    PMID: 31984923 DOI: 10.2174/1570179416666191003095253
    BACKGROUND: Sesamol is a widely used antioxidant for the food and pharmaceutical industries. The oxidation products of this compound may be accumulated in foods or ingested. Little is known about its effect on human health.

    OBJECTIVE: It is of great interest to identify the oxidation products of sesamol that may be beneficial to humans. This study was undertaken to identify the oxidation products of sesamol and investigate their antioxidant and cytotoxic activities.

    MATERIALS AND METHODS: Using the ferricyanide oxidation approach, four oxidation products of sesamol (2, 3, 20 & 21) have been identified. Structural elucidation of these compounds was established on the basis of their detailed NMR spectroscopic analysis, mass spectrometry and x-ray crystallography. Additionally, a formation mechanism of compound 20 was proposed based on high-resolution mass spectrometry-fragmentation method. The antioxidant activities of these compounds were determined by the DPPH, FRAP, and ABTS assays. The in vitro antiproliferative activity of these compounds was evaluated against a panel of human cancer cell lines as well as non-cancerous cells.

    RESULTS: Two oxidation products of sesamol were found to contain an unusual methylenedioxy ring-opening skeleton, as evidenced by spectroscopic and x-ray crystallographic data. Among all compounds, 20 displayed impressive antiproliferative activities against a panel of human cancer cell lines yet remained non-toxic to noncancerous cells. The antioxidant activities of compound 20 are significantly weaker than sesamol as determined by the DPPH, FRAP, and ABTS assays.

    CONCLUSION: The oxidation products of sesamol could be a valuable source of bioactive molecules. Compound 20 may be used as a potential lead molecule for cancer studies.

    Matched MeSH terms: Antineoplastic Agents/chemistry; Antioxidants/chemistry*; Ferricyanides/chemistry; Phenols/chemistry*; Benzodioxoles/chemistry*
  11. A protein nanocomposite for ultra-fast, efficient and non-irritating skin decontamination of nerve agents
    Wang J, Li Y, Huang J, Li W, Luo Y, Sui X, et al.
    Nanoscale, 2020 Feb 21;12(7):4400-4409.
    PMID: 32025678 DOI: 10.1039/c9nr09015k
    In recent assassinations reported in London and Malaysia, nerve agents were used to cause death, by skin poisoning. Skin decontamination is the ultimate and most important defense against nerve agent poisoning, because no effective antidote currently exists. However, almost no existing material can achieve effective and rapid decontamination without irritating the skin. This study links proteins that exhibit no decontamination ability with polymers to form a nanocomposite. This creates a nanospace on the surface of the protein that attracts and traps organic molecules, effectively adsorbing the nerve agent Soman within several seconds, without irritating the skin. Analysis of the different components of proteins and polymers reveals that the decontamination efficiency is considerably affected by the thickness of the coated polymer. Moreover, the thickness of the layer is predominantly determined by the size and species of the core and the crosslinking method. Further in vivo experiments on rats poisoned with Soman verify the efficiency and safety of the nanocomposite. These results could be used to design and synthesize more multi-functional and effective decontamination materials.
    Matched MeSH terms: Nerve Agents/chemistry*; Proteins/chemistry*; Soman/chemistry*; Coated Materials, Biocompatible/chemistry*; Nanocomposites/chemistry*
  12. Quantitation of Protein Cysteine-Phenol Adducts in Minced Beef Containing 4-Methyl Catechol
    Arsad SS, Zainudin MAM, De Gobba C, Jongberg S, Larsen FH, Lametsch R, et al.
    J Agric Food Chem, 2020 Feb 26;68(8):2506-2515.
    PMID: 32013414 DOI: 10.1021/acs.jafc.9b07752
    Thiol groups of cysteine (Cys) residues in proteins react with quinones, oxidation products of polyphenols, to form protein-polyphenol adducts. The aim of the present work was to quantify the amount of adduct formed between Cys residues and 4-methylcatechol (4MC) in minced beef. A Cys-4MC adduct standard was electrochemically synthesized and characterized by liquid chromatography-mass spectrometry (LC-MS) as well as NMR spectroscopy. Cys-4MC adducts were quantified after acidic hydrolysis of myofibrillar protein isolates (MPIs) and LC-MS/MS analysis of meat containing either 500 or 1500 ppm 4MC and stored at 4 °C for 7 days under a nitrogen or oxygen atmosphere. The concentrations of Cys-4MC were found to be 2.2 ± 0.3 nmol/mg MPI and 8.1 ± 0.9 nmol/mg MPI in meat containing 500 and 1500 ppm 4MC, respectively, and stored for 7 days under oxygen. The formation of the Cys-4MC adduct resulted in protein thiol loss, and ca. 62% of the thiol loss was estimated to account for the formation of the Cys-4MC adduct for meat containing 1500 ppm 4MC. Furthermore, protein polymerization increased in samples containing 4MC as evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and the polymerization was found to originate from protein-polyphenol interactions as evaluated by a blotting assay with staining by nitroblue tetrazolium.
    Matched MeSH terms: Cysteine/chemistry*; Guaiacol/chemistry*; Muscle Proteins/chemistry; Quinones/chemistry; Phenol/chemistry*
  13. Fulltext Preparation of kenaf stem hemicellulosic hydrolysate and its fermentability in microbial production of xylitol by Escherichia coli BL21
    Shah SSM, Luthfi AAI, Low KO, Harun S, Manaf SFA, Illias RM, et al.
    Sci Rep, 2019 03 11;9(1):4080.
    PMID: 30858467 DOI: 10.1038/s41598-019-40807-z
    Kenaf (Hibiscus cannabinus L.), a potential fibre crop with a desirably high growth rate, could serve as a sustainable feedstock in the production of xylitol. In this work, the extraction of soluble products of kenaf through dilute nitric-acid hydrolysis was elucidated with respect to three parameters, namely temperature, residence time, and acid concentration. The study will assist in evaluating the performance in terms of xylose recovery. The result point out that the maximum xylose yield of 30.7 g per 100 g of dry kenaf was attained from 2% (v/v) HNO3 at 130 °C for 60 min. The detoxified hydrolysate was incorporated as the primary carbon source for subsequent fermentation by recombinant Escherichia coli and the performance of strain on five different semi-synthetic media on xylitol production were evaluated herein. Among these media, batch cultivation in a basal salt medium (BSM) afforded the highest xylitol yield of 0.35 g/g based on xylose consumption, which corresponded to 92.8% substrate utilization after 38 h. Subsequently, fermentation by E. coli in the xylose-based kenaf hydrolysate supplemented with BSM resulting in 6.8 g/L xylitol which corresponding to xylitol yield of 0.38 g/g. These findings suggested that the use of kenaf as the fermentation feedstock could be advantageous for the development of sustainable xylitol production.
    Matched MeSH terms: Polysaccharides/chemistry*; Protein Hydrolysates/chemistry; Xylitol/chemistry; Plant Stems/chemistry; Hibiscus/chemistry*
  14. Current strategies in extending half-lives of therapeutic proteins
    Zaman R, Islam RA, Ibnat N, Othman I, Zaini A, Lee CY, et al.
    J Control Release, 2019 05 10;301:176-189.
    PMID: 30849445 DOI: 10.1016/j.jconrel.2019.02.016
    Macromolecular protein and peptide therapeutics have been proven to be effective in treating critical human diseases precisely. Thanks to biotechnological advancement, a huge number of proteins and peptide therapeutics were made their way to pharmaceutical market in past few decades. However, one of the biggest challenges to be addressed for protein therapeutics during clinical application is their fast degradation in serum and quick elimination owing to enzymatic degradation, renal clearance, liver metabolism and immunogenicity, attributing to the short half-lives. Size and hydrophobicity of protein molecules make them prone to kidney filtration and liver metabolism. On the other hand, proteasomes responsible for protein destruction possess the capability of specifically recognizing almost all kinds of foreign proteins while avoiding any unwanted destruction of cellular components. At present almost all protein-based drug formulations available in market are administered intravenously (IV) or subcutaneously (SC) with high dosing at frequent interval, eventually creating dose-fluctuation-related complications and reducing patient compliance vastly. Therefore, artificially increasing the therapeutic half-life of a protein by attaching to it a molecule that increases the overall size (eg, PEG) or helps with receptor mediated recycling (eg, albumin), or manipulating amino acid chain in a way that makes it more prone towards aggregate formation, are some of the revolutionary approaches to avoid the fast degradation in vivo. Half-life extension technologies that are capable of dramatically enhancing half-lives of proteins in circulation (2-100 folds) and thus improving their overall pharmacokinetic (PK) parameters have been successfully applied on a wide range of protein therapeutics from hormones and enzymes, growth factor, clotting factor to interferon. The focus of the review is to assess the technological advancements made so far in enhancing circulatory half-lives and improving therapeutic potency of proteins.
    Matched MeSH terms: Carbohydrates/chemistry; Peptides/chemistry; Polymers/chemistry; Proteins/chemistry; Nanoparticles/chemistry
  15. Fulltext The Health Beneficial Properties of Rhodomyrtus tomentosa as Potential Functional Food
    Vo TS, Ngo DH
    Biomolecules, 2019 02 21;9(2).
    PMID: 30795643 DOI: 10.3390/biom9020076
    Rhodomyrtus tomentosa (Aiton) Hassk. is a flowering plant belonging to the family Myrtaceae, native to southern and southeastern Asia. It has been used in traditional Vietnamese, Chinese, and Malaysian medicine for a long time for the treatment of diarrhea, dysentery, gynecopathy, stomachache, and wound healing. Moreover, R. tomentosa is used to make various food products such as wine, tea, and jam. Notably, R. tomentosa has been known to contain structurally diverse and biologically active metabolites, thus serving as a potential resource for exploring novel functional agents. Up to now, numerous phenolic and terpenoid compounds from the leaves, root, or fruits of R. tomentosa have been identified, and their biological activities such as antioxidant, antibacterial, anti-inflammatory, and anticancer have been evidenced. In this contribution, an overview of R. tomentosa and its health beneficial properties was focused on and emphasized.
    Matched MeSH terms: Anti-Inflammatory Agents/chemistry*; Anti-Bacterial Agents/chemistry*; Antineoplastic Agents, Phytogenic/chemistry*; Antioxidants/chemistry*; Myrtaceae/chemistry*
  16. Chitosan-glyoxal film as a superior adsorbent for two structurally different reactive and acid dyes: Adsorption and mechanism study
    Jawad AH, Norrahma SSA, Hameed BH, Ismail K
    Int J Biol Macromol, 2019 Aug 15;135:569-581.
    PMID: 31150675 DOI: 10.1016/j.ijbiomac.2019.05.127
    In this work, chitosan (Chi) was cross-linked with glyoxal (Gly) and deposited onto glass plate to be a superior adsorbent film for two structurally different reactive orange 16 (RO-16) and methyl orange (MO) dyes by using non-conventional adsorption system without filtration process. The characterizations indicate that the cross-linked chitosan-glyoxal (Chi-Gly) film has a low swelling index, high adherence strength on glass plate, amine group (NH2) content was 32.52%, and pHpzc of ∼6.0 indicating a negative surface charge occurs above pHpzc. The adsorption isotherm data of RO-16 and MO by Chi-Gly film were in agreement with Langmuir isotherm, with maximum adsorption capacities of 1554.3 mg/g and 1451.9 mg/g, respectively. The pseudo-first-order kinetic model best described the kinetic data. The adsorption process was spontaneous and exothermic in nature at Chi-Gly film thickness of 8.55 μm, and pH ~3. The mechanism of adsorption included mainly electrostatic attractions, dipole-dipole hydrogen bonding interactions, n-π stacking attractions, and Yoshida H-bonding. This study reveals that immobilized Chi-Gly film as a good candidate for adsorption of reactive and acid dyes as it does not require any filtration process and adsorbent recovery during and post-adsorption process.
    Matched MeSH terms: Azo Compounds/chemistry*; Coloring Agents/chemistry*; Glyoxal/chemistry*; Water Pollutants, Chemical/chemistry*; Chitosan/chemistry*
  17. Could choline chloride-citric acid monohydrate molar ratio in deep eutectic solvent affect structural, functional and antioxidant properties of pectin?
    Shafie MH, Gan CY
    Int J Biol Macromol, 2020 Apr 15;149:835-843.
    PMID: 32027904 DOI: 10.1016/j.ijbiomac.2020.02.013
    The deep eutectic solvents (DESs), which were made from different molar ratios (3:1, 2:1, 1:1, 1:2, 1:3) of choline chloride and citric acid monohydrate, were used as media for the pectic polysaccharide extraction from Averrhoa bilmbi (ABP). The physico-chemical, structural, functional and antioxidant properties of ABP were subsequently determined. The ABP was found to be xylogalacturonan. Moreover, results showed that different structures (i.e. linearity of pectin and branch size) of ABP were obtained, hence, affecting the solubility and functional properties due to the surface availability and steric effect. In addition, when increasing the molar ratio of citric acid monohydrate in DES, lower pH and higher TPC values were observed. These values were correlated with antioxidant activities (i.e. free radical scavenging activity and ferric reducing antioxidant power) of ABP. In conclusion, the molar ratio of the DES components plays an important role in extracting ABP with the aforementioned properties.
    Matched MeSH terms: Antioxidants/chemistry*; Choline/chemistry*; Pectins/chemistry*; Solvents/chemistry*; Citric Acid/chemistry*
  18. Fulltext Magnetically recoverable magnetite-reduced graphene oxide as a demulsifier for surfactant stabilized crude oil-in-water emulsion
    Yau XH, Khe CS, Mohamed Saheed MS, Lai CW, You KY, Tan WK
    PLoS One, 2020;15(4):e0232490.
    PMID: 32353051 DOI: 10.1371/journal.pone.0232490
    Oily wastewater, especially water-oil emulsion has become serious environmental issue and received global attention. Chemical demulsifiers are widely used to treat oil-water emulsion, but the toxicity, non-recyclable and non-environmental friendly characteristic of chemical demulsifiers had limited their practical application in oil-water separation. Therefore, it is imperative to develop an efficient, simple, eco-friendly and recyclable demulsifiers for breaking up the emulsions from the oily wastewater. In this study, a magnetic demulsifier, magnetite-reduced graphene oxide (M-rGO) nanocomposites were proposed as a recyclable demulsifier to break up the surfactant stabilized crude oil-in-water (O/W) emulsion. M-rGO nanocomposites were prepared via in situ chemical synthesis by using only one type Fe salt and GO solid as precursor at room temperature. The prepared composites were fully characterized by various techniques. The effect of demulsifier dosage and pH of emulsion on demulsification efficiency (ED) has been studied in detailed. The demulsification mechanism was also proposed in this study. Results showed that M-rGO nanocomposites were able to demulsify crude O/W emulsion. The ED reaches 99.48% when 0.050 wt.% of M-rGO nanocomposites were added to crude O/W emulsion (pH = 4). Besides, M-rGO nanocomposites can be recycled up to 7 cycles without showing a significant change in terms of ED. Thus, M-rGO nanocomposite is a promising demulsifier for surfactant stabilized crude O/W emulsion.
    Matched MeSH terms: Graphite/chemistry; Surface-Active Agents/chemistry*; Ferrosoferric Oxide/chemistry; Nanocomposites/chemistry*; Waste Water/chemistry*
  19. Fulltext Dielectric response of nitrogen in soil amended with chicken litter biochar and urea under Oryza sativa L. cultivation
    Maru A, Ahmed OH, Primus WC, Jeffary AV
    Sci Rep, 2021 06 15;11(1):12545.
    PMID: 34131184 DOI: 10.1038/s41598-021-91426-6
    Unbalanced utilization of nitrogen (N) rice not economically viable neither is this practice environmental friendly. Co-application of biochar and urea could reduce the unbalanced use of this N fertilizer in rice cultivation. Thus, a field study was carried out to: (i) determine the effects of chicken litter biochar and urea fertilization on N concentration in soil solution of a cultivated rice (MR219) using dielectric measurement at a low frequency and (ii) correlate soil dielectric conductivity with rice grain yield at maturity. Dielectric response of the soil samples at 20, 40, 55, and 75 days after transplanting were determined using an inductance-capacitance-resistance meter HIOKI 3522-50 LCR HiTESTER. Selected soil chemical properties and yield were determined using standard procedures. The dielectric conductivity and permittivity of the soil samples measured before transplanting the rice seedlings were higher than those for the soil samples after transplanting. This was due to the inherent nitrogen of the chicken litter biochar and the low nitrogen uptake at the transplanting stage. The soil N response increased with increasing measurement frequency and N concentration. The permittivity of the soil samples was inversely proportional to frequency but directly proportional to N concentration in the soil solution. The estimated contents of N in the soil using the dielectric conductivity approach at 1000 Hz decreased with increasing days of fertilization and the results were similar to those of soil NH4+ determined using chemical analysis. The conductivity measured within 1000 Hz and 100,000 Hz correlated positively with the rice grain yield suggesting that nitrogen concentration of the soil can be used to estimate grain yield of the cultivated rice plants.
    Matched MeSH terms: Edible Grain/chemistry; Charcoal/chemistry; Nitrogen/chemistry*; Soil/chemistry*; Urea/chemistry
  20. Effects of different polyaniline emeraldine compositions in electrodepositing ginsenoside encapsulated poly(lactic-co-glycolic acid) microcapsules coating: Physicochemical characterization and in vitro evaluation
    Lukman SK, Saidin S
    J Biomed Mater Res A, 2020 05;108(5):1171-1185.
    PMID: 31994824 DOI: 10.1002/jbm.a.36891
    Even though drug-eluting stent (DES) has prominently reduced restenosis, however, its complication of delayed endothelialization has caused chronic side effect. A coating of ginseng-based biodegradable polymer could address this issue due to its specific therapeutic values. However, deposition of this type of stable coating on metallic implant often scarce. Therefore, in this study, different polyaniline (PANI) emeraldine compositions were adopted to electrodeposit ginsenoside encapsulated poly(lactic-co-glycolic acid) microcapsules coating. The coating surfaces were analyzed using attenuated total reflectance-Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, contact angle, and atomic force microscopy instruments. A month coating stability was then investigated with an evaluation of in vitro human umbilical vein endothelial cell analyses consisted of cytotoxicity and cells attachment assessments. The 1.5 mg PANI emeraldine has assisted the formation of stable, uniform, and rounded microcapsules coating with appropriate wettability and roughness. Less than 1.5 mg PANI emeraldine was not enough to drive the formation of microcapsules coating while greater than 1.5 mg caused the deposition of melted microcapsules. The similar coating also has promoted greater cells proliferation and attachment compared to other coating variation. Therefore, the utilization of electrodeposition to deposit a drug-based polymer coating could be implemented to develop DES, in accordance to stent implantation which ultimately aims for enrich endothelialization.
    Matched MeSH terms: Aniline Compounds/chemistry*; Benzene Derivatives/chemistry*; Sulfhydryl Compounds/chemistry*; Coated Materials, Biocompatible/chemistry*; Ginsenosides/chemistry*
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