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  1. Multiboronic acid-conjugated chitosan scaffolds with glucose selectivity to insulin release
    Siddiqui NA, Billa N, Roberts CJ
    J Biomater Sci Polym Ed, 2017 Jun;28(8):781-793.
    PMID: 28278045 DOI: 10.1080/09205063.2017.1301774
    The principal challenge for the use of boronic acids (BA) as glucose sensors is their lack of specificity for glucose. We examined the selectivity of and insulin release from two boronic acids- (2-formyl-3-thienylboronic acid (FTBA) and 4-formylphenylboronic acid (FPBA)) conjugated chitosan scaffolds to glucose and fructose. Adsorption of glucose to BA: chitosan conjugates was dose-dependent up to 1:1 at 35 and 42% for FPBA and FTBA respectively but the FTBA conjugates adsorbed more glucose and fructose at respective FPBA ratios. The affinity of both BA conjugates to glucose decreased with increase in BA ratio. On the other hand, the affinity of both BA conjugates for fructose decreased from ratio 1:1 to 2:1 then rose again at 3:1. Insulin release from FPBA nanoparticles (FPBAINP) and FTBA nanoparticles (FTBAINP) were both concentration-dependent within glyceamically relevant values (1-3 mg/ml glucose and 0.002 mg/ml fructose). Furthermore, the total amounts of insulin released from FPBAINP in both the media were higher than from FTBAINP. Both FPBAINP and FTBAINP have the potential for development as a glucose-selective insulin delivery system in physiological settings.
    Matched MeSH terms: Boronic Acids/chemistry*; Drug Carriers/chemistry*; Insulin/chemistry*; Chitosan/chemistry*; Nanoparticles/chemistry
  2. Antioxidant activity, total phenolics and flavonoids contents: Should we ban in vitro screening methods?
    Granato D, Shahidi F, Wrolstad R, Kilmartin P, Melton LD, Hidalgo FJ, et al.
    Food Chem, 2018 Oct 30;264:471-475.
    PMID: 29853403 DOI: 10.1016/j.foodchem.2018.04.012
    As many studies are exploring the association between ingestion of bioactive compounds and decreased risk of non-communicable diseases, the scientific community continues to show considerable interest in these compounds. In addition, as many non-nutrients with putative health benefits are reducing agents, hydrogen donors, singlet oxygen quenchers or metal chelators, measurement of antioxidant activity using in vitro assays has become very popular over recent decades. Measuring concentrations of total phenolics, flavonoids, and other compound (sub)classes using UV/Vis spectrophotometry offers a rapid chemical index, but chromatographic techniques are necessary to establish structure-activity. For bioactive purposes, in vivo models are required or, at the very least, methods that employ distinct mechanisms of action (i.e., single electron transfer, transition metal chelating ability, and hydrogen atom transfer). In this regard, better understanding and application of in vitro screening methods should help design of future research studies on 'bioactive compounds'.
    Matched MeSH terms: Antioxidants/chemistry; Chelating Agents/chemistry; Flavonoids/chemistry; Metals/chemistry; Phenols/chemistry
  3. Equilibrium, kinetic and mechanism studies of Cu(II) and Cd(II) ions adsorption by modified chitosan beads
    Sutirman ZA, Sanagi MM, Abd Karim KJ, Wan Ibrahim WA, Jume BH
    Int J Biol Macromol, 2018 Sep;116:255-263.
    PMID: 29746971 DOI: 10.1016/j.ijbiomac.2018.05.031
    In this study, the Cu(II) and Cd(II) ions removal behavior of crosslinked chitosan beads grafted poly(methacrylamide) (abbreviated as crosslinked chitosan-g-PMAm) from single metal ion solutions was investigated. The modified chitosan beads presented a remarkable improvement in acid resistance. The batch experiments demonstrated that pH of solution played a significant role in adsorption. It was found that the adsorption of Cu(II) and Cd(II) were optimum at pH 4 and pH 5, respectively. The maximum adsorption capacities for Cu(II) and Cd(II) based on Langmuir equation were 140.9 mg g-1 and 178.6 mg g-1, respectively. Pseudo-second order gave a better fit for adsorption data with respect to linearity coefficients than pseudo-first order suggesting that chemisorption or electron transfer is the dominant mechanism of the metal ions onto crosslinked chitosan-g-PMAm. In addition, X-ray photoelectron spectroscopy (XPS) investigations revealed that adsorption of both metal ions took place on the surfaces of crosslinked chitosan-g-PMAm by chelation through CNH2, CO and CO groups. Overall, the modified chitosan has proved a promising adsorbent for removal of metal ions.
    Matched MeSH terms: Cadmium/chemistry*; Copper/chemistry*; Ions/chemistry*; Water Pollutants, Chemical/chemistry; Chitosan/chemistry*
  4. Photocatalytic degradation of oilfield produced water using graphitic carbon nitride embedded in electrospun polyacrylonitrile nanofibers
    Alias NH, Jaafar J, Samitsu S, Yusof N, Othman MHD, Rahman MA, et al.
    Chemosphere, 2018 Aug;204:79-86.
    PMID: 29653325 DOI: 10.1016/j.chemosphere.2018.04.033
    Separation and purification of oilfield produced water (OPW) is a major environmental challenge due to the co-production of the OPW during petroleum exploration and production operations. Effective capture of oil contaminant and its in-situ photodegradation is one of the promising methods to purify the OPW. Based on the photocatalytic capability of graphitic carbon nitride (GCN) which was recently rediscovered, photodegradation capability of GCN for OPW was investigated in this study. GCN was synthesized by calcination of urea and further exfoliated into nanosheets. The GCNs were incorporated into polyacrylonitrile nanofibers using electrospinning, which gave a liquid-permeable self-supporting photocatalytic nanofiber mat that can be handled by hand. The photocatalytic nanofiber demonstrated 85.4% degradation of OPW under visible light irradiation, and improved the degradation to 96.6% under UV light. Effective photodegradation of the photocatalytic nanofiber for OPW originates from synergetic effects of oil adsorption by PAN nanofibers and oil photodegradation by GCNs. This study provides an insight for industrial application on purification of OPW through photocatalytic degradation under solar irradiation.
    Matched MeSH terms: Nitriles/chemistry*; Water/chemistry*; Water Pollutants, Chemical/chemistry; Nanofibers/chemistry*; Oil and Gas Fields/chemistry*
  5. A new achievement in green degradation of aqueous organic pollutants under visible-light irradiation
    Abdollahi Y, Sabbaghi S, Abouzari-Lotf E, Jahangirian H, Sairi NA
    Water Sci Technol, 2018 Mar;77(5-6):1493-1504.
    PMID: 29595152 DOI: 10.2166/wst.2018.017
    The global attention has been focused on degradation of the environmental organic pollutants through green methods such as advanced oxidation processes (AOPs) under sunlight. However, AOPs have not yet been efficient in function of the photocatalyst that has been used. In this work, firstly, CaCu3Ti4O12 nanocomposite was simultaneously synthesized and decorated in different amounts of graphene oxide to enhance photodegradation of the organics. The result of the photocatalyst characterization showed that the sample with 8% graphene presented optimum photo-electrical properties such as low band gap energy and a great surface area. Secondly, the photocatalyst was applied for photodegradation of an organic model in a batch photoreactor. Thirdly, to scale up the process and optimize the efficiency, the photodegradation was modeled by multivariate semi-empirical methods. As the optimized condition showed, 45 mg/L of the methyl-orange has been removed at pH 5.8 by 0.96 g/L of the photocatalyst during 288 min of the light irradiation. Moreover, the photodegradation has been scaled up for industrial applications by determining the importance of the input effective variables according to the following organics order > photocatalyst > pH > irradiation time.
    Matched MeSH terms: Azo Compounds/chemistry; Graphite/chemistry; Oxides/chemistry; Water Pollutants, Chemical/chemistry*; Nanocomposites/chemistry*
  6. Influence of citric acid on the physical and biomineralization ability of freeze/thaw poly(vinyl alcohol) hydrogel
    Wahid MNA, Abd Razak SI, Abdul Kadir MR, Hassan R, Nayan NHM, Mat Amin KA
    J Biomater Appl, 2018 07;33(1):94-102.
    PMID: 29716417 DOI: 10.1177/0885328218771195
    This work reports the modification of freeze/thaw poly(vinyl alcohol) hydrogel using citric acid as the bioactive molecule for hydroxyapatite formation in simulated body fluid. Inclusion of 1.3 mM citric acid into the poly(vinyl alcohol) hydrogel showed that the mechanical strength, crystalline phase, functional groups and swelling ability were still intact. Adding citric acid at higher concentrations (1.8 and 2.3 mM), however, resulted in physically poor hydrogels. Presence of 1.3 mM of citric acid showed the growth of porous hydroxyapatite crystals on the poly(vinyl alcohol) surface just after one day of immersion in simulated body fluid. Meanwhile, a fully covered apatite layer on the poly(vinyl alcohol) surface plus the evidence of apatite forming within the hydrogel were observed after soaking for seven days. Gel strength of the soaked poly(vinyl alcohol)/citric acid-1.3 mM hydrogel revealed that the load resistance was enhanced compared to that of the neat poly(vinyl alcohol) hydrogel. This facile method of inducing rapid growth of hydroxyapatite on the hydrogel surface as well as within the hydrogel network can be useful for guided bone regenerative materials.
    Matched MeSH terms: Biocompatible Materials/chemistry*; Polyvinyl Alcohol/chemistry*; Durapatite/chemistry*; Citric Acid/chemistry*; Hydrogels/chemistry*
  7. The influences of thermal processing on phytochemicals and possible routes to the discovery of new phytochemical conjugates
    Wong FC, Chai TT, Xiao J
    Crit Rev Food Sci Nutr, 2019;59(6):947-952.
    PMID: 29787299 DOI: 10.1080/10408398.2018.1479681
    In our diets, many of the consumed foods are subjected to various forms of heating and thermal processing. Besides enhancing the taste, texture, and aroma of the foods, heating helps to sterilize and facilitate food storage. On the other hand, heating and thermal processing are frequently reported during the preparation of various traditional herbal medicines. In this review, we intend to highlight works by various research groups which reported on changes in phytochemicals and bioactivities, following thermal processing of selected plant-derived foods and herbal medicines. Relevant cases from plant-derived foods (garlic, coffee, cocoa, barley) and traditional herbal medicines (Panax ginseng, Polygonum multiforum, Aconitum carmichaelii Debeaux, Angelica sinensis Radix) will be presented in this review. Additionally, related works using pure phytochemical compounds will also be highlighted. In some of these cases, the amazing formation of new compounds were being reported. Maillard reaction could be concluded as the predominant pathway leading to the formation of new conjugates, along with other possibilities being suggested (degradation, transglycosylation, deglycosylation and dehydration). With collective efforts from all researchers, it is hoped that more details will be revealed and lead to the possible discovery of new, heat-mediated phytochemical conjugates.
    Matched MeSH terms: Hordeum/chemistry; Cacao/chemistry; Coffee/chemistry; Garlic/chemistry; Plants, Medicinal/chemistry
  8. Novel multiplex PCR-RFLP assay discriminates bovine, porcine and fish gelatin substitution in Asian pharmaceuticals capsule shells
    Sultana S, Hossain MAM, Naquiah NNA, Ali ME
    Food Addit Contam Part A Chem Anal Control Expo Risk Assess, 2018 Sep;35(9):1662-1673.
    PMID: 30028648 DOI: 10.1080/19440049.2018.1500719
    Gelatin is widely used in pharmaceuticals as a protective coating, such as soft and hard capsule shells. However, the animal source of gelatin is a sensitive issue because certain gelatins such as porcine and bovine gelatins are not welcome in Halal, Kosher and Hindus' consumer goods. Recently, we have documented DNA barcoding and multiplex PCR platforms for discriminating porcine, bovine and fish gelatins in various fish and confectionary products; but those assays were not self-authenticating and also not tested in highly refined pharmaceutical products. To address this knowledge gap, here we report a self-authenticating multiplex PCR-restriction fragment length polymorphism (RFLP) assay to identify animal sources of various gelatin in pharmaceutical capsules. Three different restriction enzymes, BsaAI, Hpy188I and BcoDI were used to yield distinctive RFLP patterns for gelatin-based bovine (26, 94 bp), fish (97, 198 bp) and porcine (17, 70 bp) DNA in control experiments. The specificity was cross-tested against 16 non-target species and the optimised assay was used to screen gelatin sources in 30 halal-branded pharmaceuticals capsule shells. Bovine and porcine DNA was found in 27 and 3 of the 30 different capsules products. The assay was suitable for detecting 0.1 to 0.01 ng total DNA extracted from pure and mixed gelatins. The study might be useful to authenticate and monitor halal, kosher, vegetarian and Hindu compliant pharmaceuticals, foods and cosmetics.
    Matched MeSH terms: Capsules/chemistry; Chemistry, Pharmaceutical; DNA/chemistry; Pharmaceutical Preparations/chemistry*; Gelatin/chemistry
  9. A tannin-based agent for coagulation and flocculation of municipal wastewater: Chemical composition, performance assessment compared to Polyaluminum chloride, and application in a pilot plant
    Hameed YT, Idris A, Hussain SA, Abdullah N
    J Environ Manage, 2016 Dec 15;184(Pt 3):494-503.
    PMID: 27789092 DOI: 10.1016/j.jenvman.2016.10.033
    Chemical composition and flocculation efficiency were investigated for a commercially produced tannin - based coagulant and flocculant (Tanfloc). The results of Fourier Transform Infrared Spectroscopy (FTIR) and Energy Dispersive Spectroscopy (EDX) confirmed what claimed about the chemical composition of Tanfloc. For moderate polluted municipal wastewater investigated in both jar test and pilot plant, Tanfloc showed high turbidity removal efficiency of approximately 90%, while removal efficiencies of BOD5 and COD were around 60%. According to floc size distribution, Tanfloc was able to show distinct performance compared to Polyaluminum chloride (PAC). While 90% of flocs produced by Tanfloc were smaller than 144 micron, they were smaller than 96 micron for PAC. Practically, zeta potential measurement showed the cationic nature of Tanfloc and suggested coincidence of charge neutralization and another flocculation mechanism (bridging or patch flocculation). Sludge Volumetric Index (SVI) measurements were in agreement with the numbers found in the literature, and they were less than 160 mL/g. Calcium cation as flocculation aid showed significant improvement of flocculation efficiency compared to other cations. Finally Tanfloc showed competing performance compared to PAC in terms of turbidity, BOD5 and COD removal, floc size and sludge characteristics.
    Matched MeSH terms: Aluminum Hydroxide/chemistry*; Sewage/chemistry; Tannins/chemistry*; Water Pollutants, Chemical/chemistry*; Waste Water/chemistry*
  10. Characterization of metabolites in different kiwifruit varieties by NMR and fluorescence spectroscopy
    Abdul Hamid NA, Mediani A, Maulidiani M, Abas F, Park YS, Leontowicz H, et al.
    J Pharm Biomed Anal, 2017 May 10;138:80-91.
    PMID: 28189049 DOI: 10.1016/j.jpba.2017.01.046
    It is known from our previous studies that kiwifruits, which are used in common human diet, have preventive properties of coronary artery disease. This study describes a combination of (1)H NMR spectroscopy, multivariate data analyses and fluorescence measurements in differentiating of some kiwifruit varieties, their quenching and antioxidant properties. A total of 41 metabolites were identified by comparing with literature data Chenomx database and 2D NMR. The binding properties of the extracted polyphenols against HSA showed higher reactivity of studied two cultivars in comparison with the common Hayward. The results showed that the fluorescence of HSA was quenched by Bidan as much as twice than by other fruits. The correlation between the binding properties of polyphenols in the investigated fruits, their relative quantification and suggested metabolic pathway was established. These results can provide possible application of fruit extracts in pharmaceutical industry.
    Matched MeSH terms: Antioxidants/chemistry; Fruit/chemistry*; Plant Extracts/chemistry; Actinidia/chemistry*; Polyphenols/chemistry
  11. 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
  12. 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*
  13. 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*
  14. 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*
  15. 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*
  16. 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*
  17. 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
  18. 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*
  19. 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*
  20. 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*
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