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  1. Salmon skin gelatin-corn zein composite films produced via crosslinking with glutaraldehyde: Optimization using response surface methodology and characterization
    Fan HY, Duquette D, Dumont MJ, Simpson BK
    Int J Biol Macromol, 2018 Dec;120(Pt A):263-273.
    PMID: 30130612 DOI: 10.1016/j.ijbiomac.2018.08.084
    Composite films comprised of salmon (Salmo salar) skin gelatin and zein were prepared via crosslinking with glutaraldehyde. Response surface methodology (RSM) was used to optimize film composition to maximize tensile strength (TS) and elongation at break (EAB), and to minimize water solubility (WS) of the films. The significant (P 
    Matched MeSH terms: Zea mays/chemistry*; Cross-Linking Reagents/chemistry*; Gelatin/chemistry*; Glutaral/chemistry*; Skin/chemistry*; Zein/chemistry*
  2. Fulltext Stability Evaluations of Different Types of Vegetable Oil-based Emulsions
    Teh SS, Mah SH
    J Oleo Sci, 2018;67(11):1381-1387.
    PMID: 30404958 DOI: 10.5650/jos.ess18067
    The study was aimed at evaluating the effects of vegetable oils on emulsion stability. Palm olein (POo), olive oil (OO), safflower oil (SAF), grape seed oil (GSO), soybean oil (SBO) and sunflower oil (SFO) with different degree of saturation levels were chosen as major ingredient of oil phases. All the emulsions were stored at 4℃, 27℃ and 40℃ for 35 days and subjected to all the stability tests, including temperature variation, centrifuge test, cycle test, pH and slip melting point. The results indicated that POo exhibited the highest stability, followed by SAF, OO, GSO, SFO and SBO. In addition, the results implied that the degree of saturation levels of vegetable oils does give significant effect on emulsion stability based on the centrifuge testing for an approximate 30% usage level of oil. The POo-based emulsion exhibited good emulsion stability throughout the experimental period indicated that POo could be a good carrier oil for various applications in cosmetic industry.
    Matched MeSH terms: Olive Oil/chemistry; Emulsions/chemistry*; Plant Oils/chemistry*; Safflower Oil/chemistry; Soybean Oil/chemistry; Grape Seed Extract/chemistry
  3. The biological activities of the spiderworts (Tradescantia)
    Tan JBL, Kwan YM
    Food Chem, 2020 Jul 01;317:126411.
    PMID: 32087517 DOI: 10.1016/j.foodchem.2020.126411
    Widely used throughout the world as traditional medicine for treating a variety of diseases ranging from cancer to microbial infections, members of the Tradescantia genus show promise as sources of desirable bioactive compounds. The bioactivity of several noteworthy species has been well-documented in scientific literature, but with nearly seventy-five species, there remains much to explore in this genus. This review aims to discuss all the bioactivity-related studies of Tradescantia plants and the compounds discovered, including their anticancer, antimicrobial, antioxidant, and antidiabetic activities. Gaps in knowledge will also be identified for future research opportunities.
    Matched MeSH terms: Anti-Infective Agents/chemistry; Antineoplastic Agents, Phytogenic/chemistry; Antioxidants/chemistry; Hypoglycemic Agents/chemistry; Plants, Medicinal/chemistry*; Tradescantia/chemistry*
  4. In vitro apatite mineralization and heat generation of magnetite-reduced graphene oxide nanocomposites for hyperthermia treatment
    Miyazaki T, Akaike J, Kawashita M, Lim HN
    Mater Sci Eng C Mater Biol Appl, 2019 Jun;99:68-72.
    PMID: 30889741 DOI: 10.1016/j.msec.2019.01.091
    Nanocomposites of magnetite (Fe3O4) and reduced graphene oxide (rGO) generate heat under an alternating magnetic field and therefore have potential applications as thermoseeds for cancer hyperthermia treatment. However, the properties of such nanocomposites as biomaterials have not been sufficiently well characterized. In this study, the osteoconductivity of Fe3O4-rGO nanocomposites of various compositions was evaluated in vitro in terms of their apatite-forming ability in simulated body fluid (SBF). Furthermore, the heat generation of the nanocomposites was measured under an alternating magnetic field. The apatite-forming ability in SBF improved as the Fe3O4 content in the nanocomposite was increased. As the Fe3O4 content was increased, the nanocomposite not only rapidly raised the surrounding temperature to approximately 100 °C, but the specific absorption rate also increased. We assumed that the ionic interaction between the Fe3O4 and rGO was enhanced and that Brown relaxation was suppressed as the proportion of rGO in the nanocomposite was increased. Consequently, a high content of Fe3O4 in the nanocomposite was effective for improving both the osteoconductivity and heat generation characteristics for hyperthermia applications.
    Matched MeSH terms: Apatites/chemistry*; Body Fluids/chemistry; Graphite/chemistry*; Minerals/chemistry*; Ferrosoferric Oxide/chemistry*; Nanocomposites/chemistry*
  5. Superabsorbent hydrogel from oil palm empty fruit bunch cellulose and sodium carboxymethylcellulose
    Salleh KM, Zakaria S, Sajab MS, Gan S, Kaco H
    Int J Biol Macromol, 2019 Jun 15;131:50-59.
    PMID: 30844455 DOI: 10.1016/j.ijbiomac.2019.03.028
    A green regenerated superabsorbent hydrogel was fabricated with mixtures of dissolved oil palm empty fruit bunch (EFB) cellulose and sodium carboxymethylcellulose (NaCMC) in NaOH/urea system. The formation of hydrogel was aided with epichlorohydrin (ECH) as a crosslinker. The resultant regenerated hydrogel was able to swell >80,000% depending on the NaCMC concentrations. The hydrogel absorbed water rapidly upon exposure to water up to 48 h and gradually declined after 72 h. The crosslinked of covalent bond of COC between dissolved EFB cellulose (EFBC) with NaCMC was confirmed with Attenuated total reflectance Fourier transform infrared (ATR-FT-IR) spectroscopy. Crystallinity and thermal stability of the hydrogel samples were depended on the concentrations of NaCMC, crosslinking, and swelling process. The strength and stability of crosslinked network was studied by examining the gel fraction of hydrogel. This study explored the swelling ability and probable influenced factors towards physical and chemical properties of hydrogel.
    Matched MeSH terms: Carboxymethylcellulose Sodium/chemistry*; Cellulose/chemistry*; Fruit/chemistry*; Water/chemistry; Hydrogels/chemistry*; Phoeniceae/chemistry*
  6. A Cytotoxic Indole Characterized by Incorporation of a Unique Carbon-Nitrogen Skeleton and Two Pentacyclic Corynanthean Alkaloids Incorporating a Substituted Tetrahydrofuranone Ring from Kopsia arborea
    Wong SK, Wong SP, Sim KS, Lim SH, Low YY, Kam TS
    J Nat Prod, 2019 07 26;82(7):1902-1907.
    PMID: 31241923 DOI: 10.1021/acs.jnatprod.9b00255
    Three new alkaloids were isolated from the bark extract of the Malayan Kopsia arborea, viz., arbophyllidine (1), an unusual pentacyclic, monoterpenoid indole characterized by an absence of oxygen atoms and incorporating a new carbon-nitrogen skeleton, and arbophyllinines A (2) and B (3), two pentacyclic corynanthean alkaloids incorporating a hydroxyethyl-substituted tetrahydrofuranone ring. The structures of the alkaloids were deduced based on analysis of the MS and NMR data and confirmed by X-ray diffraction analyses. The absolute configuration of arbophyllidine (1) was established based on experimental and calculated ECD data, while that of arbophyllinine A was based on X-ray diffraction analysis (Cu Kα). A reasonable biosynthetic route to arbophyllidine (1) from a pericine precursor is presented. Arbophyllidine (1) showed pronounced in vitro growth inhibitory activity against the HT-29 human cancer cell line with IC50 6.2 μM.
    Matched MeSH terms: Antineoplastic Agents/chemistry*; Carbon/chemistry; Furans/chemistry*; Nitrogen/chemistry; Indole Alkaloids/chemistry*; Apocynaceae/chemistry*
  7. Physicochemical and functional properties of Alcalase-extracted protein hydrolysate from oil palm leaves
    Hau EH, Teh SS, Yeo SK, Mah SH
    J Sci Food Agric, 2022 Jan 15;102(1):233-240.
    PMID: 34081335 DOI: 10.1002/jsfa.11350
    BACKGROUND: The oil palm tree produces 90% of wastes and the limited usage of these wastes causes a major disposal problem in the mills. Nevertheless, these by-products have a large amount of nutritional components. Thus, the present study aimed to determine the physicochemical and functional properties of protein hydrolysates (PH) from oil palm leaves (OPL) extracted using different concentrations of Alcalase (0-10%) at 2 h of hydrolysis time.

    RESULTS: Fourier transform infrared spectral analyses showed that the enzymatic hydrolysis altered functional groups of OPL where a secondary amine was present in the PH. Changes were also observed in the thermal stability where the enthalpy heat obtained for PH (933.93-1142.57 J g-1 ) was much lower than OPL (7854.11 J g-1 ). The results showed that the PH extracted by 8% Alcalase exhibited absolute zeta potential, as well as a high emulsifying activity index (70.64 m2  g-1 of protein) and emulsion stability index (60.58 min). Furthermore, this PH showed higher solubility (96.32%) and emulsifying properties compared to other PHs. It is also comparable with commercial plant proteins, indicating that 8% Alcalase is an optimum concentration for hydrolysis.

    CONCLUSION: In summary, the physicochemical and functional properties of PH extracted from OPL showed good functional properties, suggesting that it can be used as an alternative plant protein in food industries. © 2021 Society of Chemical Industry.

    Matched MeSH terms: Emulsions/chemistry; Plant Proteins/chemistry*; Protein Hydrolysates/chemistry; Subtilisins/chemistry; Plant Leaves/chemistry*; Arecaceae/chemistry*
  8. Use of artificial neural networks to predict drug dissolution profiles and evaluation of network performance using similarity factor
    Peh KK, Lim CP, Quek SS, Khoh KH
    Pharm Res, 2000 Nov;17(11):1384-8.
    PMID: 11205731
    PURPOSE: To use artificial neural networks for predicting dissolution profiles of matrix-controlled release theophylline pellet preparation, and to evaluate the network performance by comparing the predicted dissolution profiles with those obtained from physical experiments using similarity factor.

    METHODS: The Multi-Layered Perceptron (MLP) neural network was used to predict the dissolution profiles of theophylline pellets containing different ratios of microcrystalline cellulose (MCC) and glyceryl monostearate (GMS). The concepts of leave-one-out as well as a time-point by time-point estimation basis were used to predict the rate of drug release for each matrix ratio. All the data were used for training, except for one set which was selected to compare with the predicted output. The closeness between the predicted and the reference dissolution profiles was investigated using similarity factor (f2).

    RESULTS: The f2 values were all above 60, indicating that the predicted dissolution profiles were closely similar to the dissolution profiles obtained from physical experiments.

    CONCLUSION: The MLP network could be used as a model for predicting the dissolution profiles of matrix-controlled release theophylline pellet preparation in product development.

    Matched MeSH terms: Cellulose/chemistry; Chemistry, Pharmaceutical/methods*; Excipients/chemistry; Glycerides/chemistry; Theophylline/chemistry*
  9. Sustainable Dissolution Performance of a Carrier Tailored Electrospun
    Teoh XY, Yeoh Y, Yoong LK, Chan SY
    Pharm Res, 2020 Jan 07;37(2):28.
    PMID: 31912250 DOI: 10.1007/s11095-019-2734-0
    PURPOSE: This study aims to conduct an impact investigation in the hydrophobic-hydrophilic balance as an important factor for dissolution improvement of a hydrophilic carrier-based solid dispersion system.

    METHODS: Polymeric carriers with different hydrophobic to hydrophilic ratios were used to prepare several electrospun solid dispersion formulations. Physicochemical properties and surface morphology of the samples were assessed using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR), polarized light microscopy, Differential Scanning Calorimetry (DSC), X-ray Powder Diffraction (XRPD) and Scanning Electron Microscopy (SEM). Dissolution study was conducted in a non-sink condition to assess the drug release.

    RESULTS: Incorporation of a higher amount of hydrophilic component showed an improvement in formulating a fully amorphous system based on XRPD, yet the dissolution rate increment showed no significant difference from the lower. Hence, the degree of crystallinity is proven not to be the crucial factor contributing to dissolution rate improvement. The presence of a concomitant hydrophobic component, however, showed ability in resisting precipitation and sustaining supersaturation.

    CONCLUSION: Hydrophobicity in a binary carrier system plays an important role in achieving and maintaining the supersaturated state particularly for an amorphous solid dispersion. Graphical Abstract.

    Matched MeSH terms: Antimalarials/chemistry*; Drug Carriers/chemistry*; Polyvinyls/chemistry*; Povidone/chemistry*; Solvents/chemistry; Atovaquone/chemistry*
  10. Fulltext Utilization of Carica papaya latex on coating of SPIONs for dye removal and drug delivery
    Samrot AV, Saigeetha S, Mun CY, Abirami S, Purohit K, Cypriyana PJJ, et al.
    Sci Rep, 2021 12 31;11(1):24511.
    PMID: 34972829 DOI: 10.1038/s41598-021-03328-2
    Latex, a milky substance found in a variety of plants which is a natural source of biologically active compounds. In this study, Latex was collected from raw Carica papaya and was characterized using UV-Vis, FTIR and GC-MS analyses. Super Paramagnetic Iron Oxide Nanoparticles (SPIONs) were synthesized, coated with C. papaya latex (PL-Sp) and characterized using UV-Vis, FT-IR, SEM-EDX, XRD, VSM and Zeta potential analyses. SPIONs and latex coated SPIONs (PL-Sp) were used in batch adsorption study for effective removal of Methylene blue (MB) dye, where (PL-Sp) removed MB dye effectively. Further the PL-Sp was used to produce a nanoconjugate loaded with curcumin and it was characterized using UV-Vis spectrophotometer, FT-IR, SEM-EDX, XRD, VSM and Zeta potential. It showed a sustained drug release pattern and also found to have good antibacterial and anticancer activity.
    Matched MeSH terms: Coloring Agents/chemistry*; Latex/chemistry*; Coated Materials, Biocompatible/chemistry*; Carica/chemistry*; Magnetite Nanoparticles/chemistry*; Phytochemicals/chemistry*
  11. Fulltext 1,1'-Carbonyldiimidazole-copper nanoflower enhanced collapsible laser scribed graphene engraved microgap capacitive aptasensor for the detection of milk allergen
    Subramani IG, Perumal V, Gopinath SCB, Mohamed NM, Ovinis M, Sze LL
    Sci Rep, 2021 10 21;11(1):20825.
    PMID: 34675227 DOI: 10.1038/s41598-021-00057-4
    The bovine milk allergenic protein, 'β-lactoglobulin' is one of the leading causes of milk allergic reaction. In this research, a novel label-free non-faradaic capacitive aptasensor was designed to detect β-lactoglobulin using a Laser Scribed Graphene (LSG) electrode. The graphene was directly engraved into a microgapped (~ 95 µm) capacitor-electrode pattern on a flexible polyimide (PI) film via a simple one-step CO2 laser irradiation. The novel hybrid nanoflower (NF) was synthesized using 1,1'-carbonyldiimidazole (CDI) as the organic molecule and copper (Cu) as the inorganic molecule via one-pot biomineralization by tuning the reaction time and concentration. NF was fixed on the pre-modified PI film at the triangular junction of the LSG microgap specifically for bio-capturing β-lactoglobulin. The fine-tuned CDI-Cu NF revealed the flower-like structures was viewed through field emission scanning electron microscopy. Fourier-transform infrared spectroscopy showed the interactions with PI film, CDI-Cu NF, oligoaptamer and β-lactoglobulin. The non-faradaic sensing of milk allergen β-lactoglobulin corresponds to a higher loading of oligoaptamer on 3D-structured CDI-Cu NF, with a linear range detection from 1 ag/ml to 100 fg/ml and attomolar (1 ag/ml) detection limit (S/N = 3:1). This novel CDI-Cu NF/LSG microgap aptasensor has a great potential for the detection of milk allergen with high-specificity and sensitivity.
    Matched MeSH terms: Copper/chemistry*; Graphite/chemistry; Imidazoles/chemistry*; Milk/chemistry*; Nanostructures/chemistry; Aptamers, Nucleotide/chemistry*
  12. Impedimetric cardiac biomarker determination in serum mediated by epoxy and hydroxyl of reduced graphene oxide on gold array microelectrodes
    Taniselass S, Arshad MKM, Gopinath SCB, Fathil MFM, Ibau C, Anbu P
    Mikrochim Acta, 2021 07 15;188(8):257.
    PMID: 34268634 DOI: 10.1007/s00604-021-04922-x
    A label-free chemical bonding strategy mediated by reduced graphene oxide (rGO) basal plane functional groups has been developed for cardiac Troponin I (cTnI) detection. Four different chemical strategies on respective electrode sensing surface were precedingly examined using electrochemical impedance spectroscopy. The impedimetric assessment was carried out by sweeping frequency at the range 0.1-500 kHz perturbated at a small amplitude of AC voltage (25 mV). The chemical strategy-4 denoted as S-4 shows a significant analytical performance on cTnI detection in spiked buffer and human serum, whereby the pre-mixture of rGO and (3-Aminopropyl)triethoxysilane (APTES) creates a large number of amine sites (-NH2), which significantly enhanced the antibody immobilization without excessive functionalization. The as-fabricated immunosensor exhibited an ultra-low limit of detection of 6.3 ag mL-1 and the lowest antigen concentration measured was at 10 ag mL-1. The immunosensor showed a linear and wide range of cTnI detection (10 ag mL-1-100 ng mL-1) in human serum with a regression coefficient of 0.9716, rapid detection (5 min of binding time), and stable and highly reproducible bioelectrode response with RSD 
    Matched MeSH terms: Epoxy Compounds/chemistry; Gold/chemistry*; Graphite/chemistry*; Hydroxides/chemistry; Propylamines/chemistry; Silanes/chemistry
  13. Multi-metals column adsorption of lead(II), cadmium(II) and manganese(II) onto natural bentonite clay
    Alexander JA, Surajudeen A, Aliyu EU, Omeiza AU, Zaini MAA
    Water Sci Technol, 2017 Oct;76(7-8):2232-2241.
    PMID: 29068353 DOI: 10.2166/wst.2017.391
    The present work was aimed at evaluating the multi-metals column adsorption of lead(II), cadmium(II) and manganese(II) ions onto natural bentonite. The bentonite clay adsorbent was characterized for physical and chemical properties using X-ray diffraction, X-ray fluorescence, Brunauer-Emmett-Teller surface area and cation exchange capacity. The column performance was evaluated using adsorbent bed height of 5.0 cm, with varying influent concentrations (10 mg/L and 50 mg/L) and flow rates (1.4 mL/min and 2.4 mL/min). The result shows that the breakthrough time for all metal ions ranged from 50 to 480 minutes. The maximum adsorption capacity was obtained at initial concentration of 10 mg/L and flow rate of 1.4 mL/min, with 2.22 mg/g of lead(II), 1.71 mg/g of cadmium(II) and 0.37 mg/g of manganese(II). The order of metal ions removal by natural bentonite is lead(II) > cadmium(II) > manganese(II). The sorption performance and the dynamic behaviour of the column were predicted using Adams-Bohart, Thomas, and Yoon-Nelson models. The linear regression analysis demonstrated that the Thomas and Yoon-Nelson models fitted well with the column adsorption data for all metal ions. The natural bentonite was effective for the treatment of wastewater laden with multi-metals, and the process parameters obtained from this work can be used at the industrial scale.
    Matched MeSH terms: Bentonite/chemistry*; Cadmium/chemistry*; Lead/chemistry*; Manganese/chemistry*; Water Pollutants, Chemical/chemistry*; Waste Water/chemistry
  14. Fulltext New Biflavonoids with α-Glucosidase and Pancreatic Lipase Inhibitory Activities from Boesenbergia rotunda
    Chatsumpun N, Sritularak B, Likhitwitayawuid K
    Molecules, 2017 Oct 30;22(11).
    PMID: 29084164 DOI: 10.3390/molecules22111862
    Roots of Boesenbergia rotunda (L.) Mansf. are prominent ingredients in the cuisine of several Asian countries, including Thailand, Malaysia, Indonesia, India, and China. An extract prepared from the roots of this plant showed strong inhibitory activity against enzymes α-glucosidase and pancreatic lipase and was subjected to chromatographic separation to identify the active components. Three new biflavonoids of the flavanone-chalcone type (9, 12, and 13) were isolated, along with 12 known compounds. Among the 15 isolates, the three new compounds showed stronger inhibitory activity against α-glucosidase than the drug acarbose but displayed lower pancreatic lipase inhibitory effect than the drug orlistat. The results indicated the potential of B. rotunda roots as a functional food for controlling after-meal blood glucose levels.
    Matched MeSH terms: Enzyme Inhibitors/chemistry; Plant Extracts/chemistry; Plant Roots/chemistry; Zingiberaceae/chemistry*; Biflavonoids/chemistry; Glycoside Hydrolase Inhibitors/chemistry
  15. Antioxidant potential assessment of phenolic and flavonoid rich fractions of Clematis orientalis and Clematis ispahanica (Ranunculaceae)
    Karimi E, Ghorbani Nohooji M, Habibi M, Ebrahimi M, Mehrafarin A, Khalighi-Sigaroodi F
    Nat Prod Res, 2018 Aug;32(16):1991-1995.
    PMID: 28774179 DOI: 10.1080/14786419.2017.1359171
    The antioxidant activities of crude extract fractions using Hexane, Chloroform, Ethyl Acetate, Butanol and Water of Clematis orientalis and Clematis ispahanica were investigated. 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay and the ferric reducing/antioxidant potential (FRAP) were used to evaluate the antioxidant capacity. The total phenolics were found to be 4.37-9.38 and 1.32-11.37 mg gallic acid equivalents (GAE)/g in different fractions for C. orientalis and C. ispahanica, respectively. The ethyl acetate fraction of C. orientalis and chloroform fraction of C. ispahanica showed the highest DPPH and FRAP activities at a concentration of 300 μg/mL. The predominant phenolic compounds identified by HPLC in C. orientalis were Resorcinol (603.5 μg/g DW) in chloroform fraction and Ellagic acid (811.7 μg/g DW) in chloroform fraction of C. ispahanica.
    Matched MeSH terms: Antioxidants/chemistry; Flavonoids/chemistry*; Phenols/chemistry*; Plant Extracts/chemistry*; Ranunculaceae/chemistry; Clematis/chemistry*
  16. Evaluation of extraction methods for the identification of proteins from date palm (Phoenix dactylifera L.) seed and flesh
    Lee HX, Ahmad F, Saad B, Ismail MN
    Prep Biochem Biotechnol, 2017 Nov 26;47(10):998-1007.
    PMID: 28857669 DOI: 10.1080/10826068.2017.1365250
    Date fruits are well known to be very nutritious. Nevertheless, the protein contents of the fruit, particularly the seed and flesh, are still understudied, largely due to their difficult physical characteristics. This study was conducted to compare three different protein extraction methods which were the trichloroacetic acid (TCA)-acetone (TCA-A), phenol (Phe), and TCA-acetone-phenol (TCA-A-Phe), and to perform proteomic analysis on date palm seed and flesh. Phe extraction method showed the highest protein yields for both seed (8.26 mg/g) and flesh (1.57 mg/g). Through sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Phe, and TCA-A-Phe extraction methods were shown to be efficient in removing interfering compounds and gave well-resolved bands over a wide range of molecular weights. Following liquid chromatography-tandem mass spectrometry analysis, about 50-64% of extracted proteins were identified with known functions including those involved in glycolysis, Krebs cycle, defense, and storage. Phe protein extraction method was proven to be the optimal method for date flesh and seed.
    Matched MeSH terms: Acetone/chemistry; Fruit/chemistry*; Seeds/chemistry*; Trichloroacetic Acid/chemistry; Phenol/chemistry; Phoeniceae/chemistry*
  17. Secondary metabolites from endemic species Iris adriatica Trinajstić ex Mitić (Iridaceae)
    Bukvički D, Novaković M, Ab Ghani N, Marin PD, Asakawa Y
    Nat Prod Res, 2018 Aug;32(15):1849-1852.
    PMID: 29126369 DOI: 10.1080/14786419.2017.1402309
    This manuscript describes the first detailed chemical investigation of endemic species Iris adriatica, including isolation and structure elucidation. Chemical analyses of the rhizome CH2Cl2/MeOH (2:1) extract revealed fourteen secondary metabolites, mainly isoflavonoids. Among isoflavonoids, two groups have been found: nigricin-type and tectorigenin-type. Dominant group of the isolated compounds has been nigricin-type isoflavones: nigricin, nigricin-4'-(1-O-β-D-glucopyranoside) and nigricin-4'-(1-O-β-D-glucopyranosyl (1-6)-β-D-glucopyranoside) with 2.5, 10 and 1% of the total extract, respectively. Irisxanthone - xanthone C-glucoside, β-sitosterol, benzophenone and one of its derivatives have also been found. Nigricin-type isoflavonoids and irisxanthone can be considered as possible chemotaxonomic markers for I. adriatica. 5,3',5'-Trimethoxy-6,7-methylenedioxyisoflavone-4'-(1-O-β-D-glucopyranoside) and benzophenone have been isolated from Iris species for the first time.
    Matched MeSH terms: Benzophenones/chemistry; Glucosides/chemistry; Isoflavones/chemistry; Plant Extracts/chemistry; Rhizome/chemistry; Iris Plant/chemistry*
  18. Revalorization of selected municipal solid wastes as new precursors of "green" nanocellulose via a novel one-pot isolation system: A source perspective
    Chen YW, Lee HV
    Int J Biol Macromol, 2018 Feb;107(Pt A):78-92.
    PMID: 28860064 DOI: 10.1016/j.ijbiomac.2017.08.143
    In the present work, four types of newly chosen municipal solid wastes (Panax ginseng, spent tea residue, waste cotton cloth, and old corrugated cardboard) were studied as the promising sources for nanocellulose, which has efficiently re-engineered the structure of waste products into highly valuable nanocellulose materials. The nanocellulose was produced directly via a facile one-pot oxidative hydrolysis process by using H2O2/Cr(NO3)3 solution as the bleaching agent and hydrolysis medium under acidic condition. The isolated nanocellulose products were well-characterized in terms of chemical composition, product yield, morphological structure and thermal properties. The study has found that the crystallinity index of the obtained nanocellulose products were significantly higher (62.2-83.6%) than that of its starting material due to the successive elimination of lignin, hemicellulose and amorphous regions of cellulose, which were in good agreement with the FTIR analysis. The evidence of the successful production of nanocellulose was given by TEM observation which has revealed the fibril widths were ranging from 15.6 to 46.2nm, with high cellulose content (>90%), depending on the cellulosic origin. The physicochemical properties of processed samples have confirmed that the isolation of high purity nanocellulose materials from different daily spent products is possible. The comparative study can help to provide a deep insight on the possibility of revalorizing the municipal solid wastes into nanocellulose via the simple and versatile one-pot isolation system, which has high potential to be used in commercial applications for sustainable development.
    Matched MeSH terms: Cellulose/chemistry*; Panax/chemistry; Polysaccharides/chemistry*; Tea/chemistry; Nanostructures/chemistry; Nanocomposites/chemistry*
  19. Synthesis and characterization of cellulose and hydroxyapatite-carbon electrode composite for trace plumbum ions detection and its validation in blood serum
    Ajab H, Dennis JO, Abdullah MA
    Int J Biol Macromol, 2018 Jul 01;113:376-385.
    PMID: 29486259 DOI: 10.1016/j.ijbiomac.2018.02.133
    A novel synthesis and characterization of cellulose, hydroxyapatite and chemically-modified carbon electrode (Cellulose-HAp-CME) composite was reported for the analysis of trace Pb(II) ions detection and its validation in blood serum. The Field Emission Scanning Electron Microscopy (FESEM) analyses showed that the composite retained the orderly porous structure but with scattered particle size agglomeration. The Fourier Transform Infrared Spectroscopy (FTIR) spectra suggested the presence of functional groups associated with the bending and stretching of carbon bonds and intermolecular H-bonding. X-ray Diffraction (XRD) analyses further elucidated that the crystallite size could have influenced the properties of the electrode. Based on Thermo-gravimetric Analysis (TGA/DTG), the composites showed thermal stability with more than 60% residual content at 700°C. The sensor was successfully developed for trace Pb(II) ions detection in complex medium such as blood serum, in the physiologically relevant range of 10-60ppb, with resulting Limit of Detection (LOD) of 0.11±0.36ppb and Limit of Quantification (LOQ) of 0.36±0.36ppb. The newly fabricated electrode could be advantageous as a sensing platform with favourable electrochemical characteristics for robust, in situ and rapid environmental and clinical analyses of heavy metal ions.
    Matched MeSH terms: Carbon/chemistry*; Cellulose/chemistry*; Electrochemistry; Lead/chemistry*; Water/chemistry; Durapatite/chemistry*; Chemistry Techniques, Synthetic
  20. Fulltext Kinetics and Optimization of Lipophilic Kojic Acid Derivative Synthesis in Polar Aprotic Solvent Using Lipozyme RMIM and Its Rheological Study
    Ishak N, Lajis AFB, Mohamad R, Ariff AB, Mohamed MS, Halim M, et al.
    Molecules, 2018 Feb 24;23(2).
    PMID: 29495254 DOI: 10.3390/molecules23020501
    The synthesis of kojic acid derivative (KAD) from kojic and palmitic acid (C16:0) in the presence of immobilized lipase from Rhizomucor miehei (commercially known as Lipozyme RMIM), was studied using a shake flask system. Kojic acid is a polyfunctional heterocycles that acts as a source of nucleophile in this reaction allowing the formation of a lipophilic KAD. In this study, the source of biocatalyst, Lipozyme RMIM, was derived from the lipase of Rhizomucor miehei immobilized on weak anion exchange macro-porous Duolite ES 562 by the adsorption technique. The effects of solvents, enzyme loading, reaction temperature, and substrate molar ratio on the reaction rate were investigated. In one-factor-at-a-time (OFAT) experiments, a high reaction rate (30.6 × 10-3 M·min-1) of KAD synthesis was recorded using acetone, enzyme loading of 1.25% (w/v), reaction time of 12 h, temperature of 50 °C and substrate molar ratio of 5:1. Thereafter, a yield of KAD synthesis was optimized via the response surface methodology (RSM) whereby the optimized molar ratio (fatty acid: kojic acid), enzyme loading, reaction temperature and reaction time were 6.74, 1.97% (w/v), 45.9 °C, and 20 h respectively, giving a high yield of KAD (64.47%). This condition was reevaluated in a 0.5 L stirred tank reactor (STR) where the agitation effects of two impellers; Rushton turbine (RT) and pitch-blade turbine (PBT), were investigated. In the STR, a very high yield of KAD synthesis (84.12%) was achieved using RT at 250 rpm, which was higher than the shake flask, thus indicating better mixing quality in STR. In a rheological study, a pseudoplastic behavior of KAD mixture was proposed for potential application in lotion formulation.
    Matched MeSH terms: Acetone/chemistry; Lipase/chemistry*; Pyrones/chemistry*; Solvents/chemistry*; Rhizomucor/chemistry*; Chemistry Techniques, Synthetic
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