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Thermal and dynamic mechanical properties of cellulose nanofibers reinforced epoxy composites

Saba N, Safwan A, Sanyang ML, Mohammad F, Pervaiz M, Jawaid M, et al.

Int J Biol Macromol, 2017 Sep;102:822-828.
PMID: 28455253 DOI: 10.1016/j.ijbiomac.2017.04.074

The current study presents about the effect of cellulose nanofibers (CNFs) filler on the thermal and dynamic mechanical analysis (DMA) of epoxy composites as a function of temperature. In this study hand lay-up method was used to fabricate CNF reinforced Epoxy nanocomposites with CNF loading of 0.5%, 0.75%, and 1% into epoxy resin. The obtained thermal and DMA results illustrates that thermal stability, char content, storage modulus (E'), loss modulus (E") and glass transition temperature (Tg) increases for all CNF/epoxy nanocomposites compared to the pure epoxy. Thermal results revealed that 0.75% offers superior resistance or stability towards heat compared to its counterparts. In addition, 0.75% CNF/epoxy nanocomposites confers highest value of storage modulus as compared to 0.5% and 1% filler loading. Hence, it is concluded that 0.75% CNFs loading is the minimal to enhance both thermal and dynamic mechanical properties of the epoxy composites and can be utilized for advance material applications where thermal stability along with renewability are prime requirements.

Matched MeSH terms: Cellulose/chemistry*; Epoxy Compounds/chemistry*; Nanofibers/chemistry*
Fulltext Green Tea Leaves Extract: Microencapsulation, Physicochemical and Storage Stability Study

Zokti JA, Sham Baharin B, Mohammed AS, Abas F

Molecules, 2016 Jul 26;21(8).
PMID: 27472310 DOI: 10.3390/molecules21080940

Green tea polyphenols have been reported to possess many biological properties. Despite the many potential benefits of green tea extracts, their sensitivity to high temperature, pH and oxygen is a major disadvantage hindering their effective utilization in the food industry. Green tea leaves from the Cameron Highlands Malaysia were extracted using supercritical fluid extraction (SFE). To improve the stability, green tea extracts were encapsulated by spray-drying using different carrier materials including maltodextrin (MD), gum arabic (GA) and chitosan (CTS) and their combinations at different ratios. Encapsulation efficiency, total phenolic content and antioxidant capacity were determined and were found to be in the range of 71.41%-88.04%, 19.32-24.90 (g GAE/100 g), and 29.52%-38.05% respectively. Further analysis of moisture content, water activity, hygroscopicity, bulk density and mean particles size distribution of the microparticles were carried out and the results ranged from; 2.31%-5.11%, 0.28-0.36, 3.22%-4.71%, 0.22-0.28 g/cm³ and 40.43-225.64 µm respectively. The ability of the microparticles to swell in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) was determined as 142.00%-188.63% and 207.55%-231.77%, respectively. Release of catechin polyphenol from microparticles in SIF was higher comparable to that of SGF. Storage stability of encapsulated catechin extracts under different temperature conditions was remarkably improved compared to non-encapsulated extract powder. This study showed that total catechin, total phenolic content (TPC) and antioxidant activity did not decrease significantly (p ≥ 0.05) under 4 °C storage conditions. The half-life study results were in the range of 35-60, 34-65 and 231-288 weeks at storage temperatures of 40 °C, 25 °C and 4 °C respectively, therefore, for improved shelf-life stability we recommend that microparticles should be stored at temperatures below 25 °C.

Matched MeSH terms: Antioxidants/chemistry; Gum Arabic/chemistry; Plant Extracts/chemistry; Polysaccharides/chemistry; Tea/chemistry*; Plant Leaves/chemistry; Chitosan/chemistry; Polyphenols/chemistry*
Fulltext PHYTOCHEMICAL, PHARMACOLOGICAL AND BIOLOGICAL PROFILES OF TRAGIA SPECIES (FAMILY: EUPHORBIACEAE)

Reddy BS, Rao NR, Vijeepallam K, Pandy V

Afr J Tradit Complement Altern Med, 2017;14(3):105-112.
PMID: 28480421 DOI: 10.21010/ajtcam.v14i3.11

BACKGROUND: Tragia belongs to the family Euphorbiaceae which contains about 152 species. Interestingly, most of the earlier investigations have been done using only five Tragia species, namely, Tragia involucrata, Tragia cannabina, Tragia spathulata, Tragia plukenetii, and Tragia benthamii. The objective of the present review is to compile the phytochemical, pharmacological and biological studies of the selected five Tragia species reported in the literature.
METHODS: The reported data/information was retrieved mainly from the online databases of PubMed (MEDLINE), EMBASE and Botanical Survey of India.
RESULTS: The present review elaborated the phytochemical, pharmacological and biological properties of the selected five Tragia species obtained from recent literature.
CONCLUSION: This review provides a basis for future investigation of Tragia species and, especially for those species that have not been explored for biological and pharmacological activities.

Matched MeSH terms: Plant Extracts/chemistry; Euphorbiaceae/chemistry*; Phytochemicals/chemistry
Pectin as a rheology modifier: Origin, structure, commercial production and rheology

Chan SY, Choo WS, Young DJ, Loh XJ

Carbohydr Polym, 2017 Apr 01;161:118-139.
PMID: 28189220 DOI: 10.1016/j.carbpol.2016.12.033

Pectins are a diverse family of biopolymers with an anionic polysaccharide backbone of α-1,4-linked d-galacturonic acids in common. They have been widely used as emulsifiers, gelling agents, glazing agents, stabilizers, and/or thickeners in food, pharmaceutical, personal care and polymer products. Commercial pectin is classified as high methoxy pectin (HMP) with a degree of methylation (DM) >50% and low methoxy pectin (LMP) with a DM <50%. Amidated low methoxy pectins (ALMP) can be obtained through aminolysis of HMP. Gelation of HMP occurs by cross-linking through hydrogen bonds and hydrophobic forces between the methyl groups, assisted by a high co-solute concentration and low pH. In contrast, gelation of LMP occurs by the formation of ionic linkages via calcium bridges between two carboxyl groups from two different chains in close proximity, known as the 'egg-box' model. Pectin gels exhibit Newtonian behaviour at low shear rates and shear-thinning behaviour when the shear rate is increased. An overview of pectin from its origin to its physicochemical properties is presented in this review.

Matched MeSH terms: Gels/chemistry; Pectins/chemistry*; Polymers/chemistry
Effect of different types and concentrations of emulsifier on the characteristics of kappa-carrageenan films

Nur Hanani ZA, Aelma Husna AB

Int J Biol Macromol, 2018 Jul 15;114:710-716.
PMID: 29601881 DOI: 10.1016/j.ijbiomac.2018.03.163

κ-Carrageenan films derived from Euchema cottoni containing different types and concentrations of emulsifier were developed. Film formation without the addition of emulsifier was used as a control. The physical, mechanical, optical and microstructural properties of these films were determined. Different types of emulsifiers (Tween 20, Tween 40 and Tween 80) exerted significant effects (P≤0.05) on the thickness, moisture content and opacity of the films. Additionally, Tween 20 and Tween 40 with concentrations from 0.1 to 0.5% (v/v) significantly (P≤0.05) improved the tensile strength of the films, ranging from 7.35 to 13.83MPa. The water vapor permeability of the carrageenan films was significantly (P≤0.05) affected by both factors. Increasing the emulsifier concentration also caused an increment in the number of lipid droplets contributing to a smooth surface. Therefore, this study suggests that different types and concentrations of emulsifiers play essential roles in determining the physical properties of carrageenan films.

Matched MeSH terms: Carrageenan/chemistry*; Gossypium/chemistry*; Emulsifying Agents/chemistry*
Enhanced removal of lead from contaminated soil by polyol-based deep eutectic solvents and saponin

Mukhopadhyay S, Mukherjee S, Hayyan A, Hayyan M, Hashim MA, Sen Gupta B

J Contam Hydrol, 2016 Nov;194:17-23.
PMID: 27697607 DOI: 10.1016/j.jconhyd.2016.09.007

Deep eutectic solvents (DESs) are a class of green solvents analogous to ionic liquids, but less costly and easier to prepare. The objective of this study is to remove lead (Pb) from a contaminated soil by using polyol based DESs mixed with a natural surfactant saponin for the first time. The DESs used in this study were prepared by mixing a quaternary ammonium salt choline chloride with polyols e.g. glycerol and ethylene glycol. A natural surfactant saponin obtained from soapnut fruit pericarp, was mixed with DESs to boost their efficiency. The DESs on their own did not perform satisfactory due to higher pH; however, they improved the performance of soapnut by up to 100%. Pb removal from contaminated soil using mixture of 40% DES-Gly and 1% saponin and mixture of 10% DES-Gly and 2% saponin were above 72% XRD and SEM studies did not detect any major corrosion in the soil texture. The environmental friendliness of both DESs and saponin and their affordable costs merit thorough investigation of their potential as soil washing agents.

Matched MeSH terms: Choline/chemistry; Glycerol/chemistry; Lead/chemistry*; Saponins/chemistry*; Soil/chemistry; Soil Pollutants/chemistry*; Surface-Active Agents/chemistry*; Ethylene Glycol/chemistry
Analysis of heavy metals as a key indicator to predict shallow slope failure

Othman R, Hasni SI, Baharuddin ZM

J Environ Biol, 2016 09;37(5 Spec No):1181-1185.
PMID: 29989751

Degradation or decline of soil quality that cause shallow slope failure may occur due to physical or chemical processes. It can be triggered off by natural phenomena, or induced by human activity through misuse of land resources, excessive development and urbanization leading to deforestation and erosion of covered soil masses causing serious threat to slopes. The extent of damage of the slopes can be minimized if a long-term early warning system is predicted in the landslide prone areas. The aim of the study was to characterize chemical properties of stable and unstable slope along selected highways of Malaysia which can be manipulated as indicator to forecast shallow slope failure. The elements in soil chemical properties contributed to each other as binding agents that affected the existing soil structure. It could make the soil structure strong or weak. Indicators that can be used to predict shallow slope failure were low content in iron, lead, aluminum, chromium, zinc, low content of organic carbon and CEC.

Matched MeSH terms: Soil/chemistry; Soil Pollutants/chemistry*; Metals, Heavy/chemistry*
Modulation of osteoblast behavior on nanopatterned yttria-stabilized zirconia surfaces

Soon G, Pingguan-Murphy B, Akbar SA

J Mech Behav Biomed Mater, 2017 04;68:26-31.
PMID: 28135639 DOI: 10.1016/j.jmbbm.2017.01.028

This study utilizes the technique of self-assembly to fabricate arrays of nanoislands on (001)-oriented yttria-stabilized zirconia single crystal substrates with miscut of 10° toward <110> direction. These self-assembled nanostructures were annealed at 1100°C for 5h upon doping with 10mol% gadolinium-doped ceria (GDC) by powder-suspension based method. X-Ray diffraction result showed that the miscut substrate after doping GDC was in the cubic phase. Energy dispersive X-ray (EDX) illustrates that the nanopatterned material contains all the elements from the GDC source and yttria-stabilized zirconia (YSZ) substrate. It also demonstrates a higher surface roughness and a more hydrophilic surface. The nanostructured materials were subsequently used for an in vitro study using a human fetal osteoblastic cell line (hFOB). An improved spreading, enhanced cell proliferation and up-regulated alkaline phosphatase activity (ALP) were observed on the nanopatterned substrates compared to the control substrates. Calcium deposits, which were stained positively by Alizarin Red S, appeared to be more abundant on the nanopatterned surfaces on day 7. The overall findings suggest that post fabrication treatment with surface modification such as creating a nanostructure (e.g. nanopatterns) can improve biocompatibility.

Matched MeSH terms: Yttrium/chemistry*; Zirconium/chemistry*; Nanostructures/chemistry*
Efficacy and Safety of Cissus quadrangularis L. in Clinical Use: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Sawangjit R, Puttarak P, Saokaew S, Chaiyakunapruk N

Phytother Res, 2017 Apr;31(4):555-567.
PMID: 28165166 DOI: 10.1002/ptr.5783

Cissus quadrangularis L. (Cissus) is a medicinal plant commonly used for centuries for various conditions, but lacks critical appraisal of its clinical effects. This study aimed to determine the efficacy and safety of Cissus in all conditions. Publications from 12 electronic databases were searched from inception through November 2016. A total of nine studies with 1108 patients were included. Each outcome was pooled using a random effects model. Effects of Cissus on hemorrhoid symptoms were not different from any comparators but had significant effects on bone pain. Effects of Cissus combination products on body weight reduction, low-density lipoprotein, triglyceride, total cholesterol, and fasting blood sugar were superior to placebo, with weighted mean difference of -5.19 kg (-8.82, -1.55), -14.43 mg/dl (-20.06, -8.80), -37.50 mg/dl (-48.71, -26.29), -50.50 mg/dl (-70.97, -30.04), and -10.39 mg/dl (-14.60, -6.18), respectively. No serious adverse effects were reported. Quality of evidence based on Grades of Recommendations Assessment Development and Evaluation (GRADE) indicated low (bone fractures) to high quality (hemorrhoids, body weight reduction).In conclusion, Cissus had benefit for bone fractures, but not for hemorrhoids. For obesity/overweight, only combination products are pooled and show benefit. However, high-quality studies remain needed. Copyright © 2017 John Wiley & Sons, Ltd.

Matched MeSH terms: Biological Products/chemistry*; Plant Extracts/chemistry*; Cissus/chemistry*
A review on processing techniques of bast fibers nanocellulose and its polylactic acid (PLA) nanocomposites

Kian LK, Saba N, Jawaid M, Sultan MTH

Int J Biol Macromol, 2019 Jan;121:1314-1328.
PMID: 30208300 DOI: 10.1016/j.ijbiomac.2018.09.040

The utilization of nanocellulose has increasingly gained attentions from various research fields, especially the field of polymer nanocomposites owing to the growing environmental hazardous of petroleum based fiber products. Meanwhile, the searching of alternative cellulose sources from different plants has become the interests for producing nanocellulose with varying characterizations that expectedly suit in specific field of applications. In this content the long and strong bast fibers from plant species was gradually getting its remarkable position in the field of nanocellulose extraction and nanocomposites fabrications. This review article intended to present an overview of the chemical structure of cellulose, different types of nanocellulose, bast fibers compositions, structure, polylactic acid (PLA) and the most probable processing techniques on the developments of nanocellulose from different bast fibers especially jute, kenaf, hemp, flax, ramie and roselle and its nanocomposites. This article however more focused on the fabrication of PLA based nanocomposites due to its high firmness, biodegradability and sustainability properties in developed products towards the environment. Along with this it also explored a couple of issues to improve the processing techniques of bast fibers nanocellulose and its reinforcement in the PLA biopolymer as final products.

Matched MeSH terms: Cellulose/chemistry*; Polyesters/chemistry*; Nanocomposites/chemistry*
Choline-Chloride-Based Eutectic Solvent for the Efficient Production of Docosahexaenoyl and Eicosapentaenoyl Ethanolamides via an Enzymatic Process

Liang H, Qin X, Tan CP, Li D, Wang Y

J Agric Food Chem, 2018 Nov 21;66(46):12361-12367.
PMID: 30394748 DOI: 10.1021/acs.jafc.8b04804

Docosahexaenoyl and eicosapentaenoyl ethanolamides (DHEA and EPEA) have physiological functions, including immunomodulation, brain development, and anti-inflammation, but their efficient production is still unresolved. In this study, choline-chloride-based natural deep eutectic solvents are used as media to improve the production of DHEA and EPEA. The water content showed a key effect on the reactant conversion. Adding water to choline chloride-glucose (CG, molar ratio of 5:2) led to a significant increase (13.03% for EPEA and 27.95% for DHEA) in the yields after 1 h. The high yields of EPEA (96.84%) and DHEA (90.06%) were obtained under the optimized conditions [fish oil ethyl esters/ethanolamine molar ratio of 1:2, temperature of 60 °C, 1 h, enzyme loading of 2195 units, and CG containing 8.50% water of 43.30% (w/w, relative to total reactants)]. The products could be easily separated using centrifugation. In summary, the research has the potential to produce fatty acyl ethanolamides.

Matched MeSH terms: Choline/chemistry*; Docosahexaenoic Acids/chemistry; Fatty Acids, Unsaturated/chemistry; Lipase/chemistry*; Eicosapentaenoic Acid/chemistry; Ethanolamine/chemistry*; Green Chemistry Technology/methods*
Thermodynamics and solute-solvent interactions of lovastatin in an aqueous arginine solution

Zolkiflee NF, Affandi MMRMM, Majeed ABA

Eur J Pharm Sci, 2020 Jan 01;141:105111.
PMID: 31629916 DOI: 10.1016/j.ejps.2019.105111

Lovastatin (LVS) is an effective therapeutic and prophylactic agent in several cardiovascular disorders. However, it has low bioavailability. This study investigated solute-solvent and solute-cosolute interactions and assessed thermodynamic parameters that contributed to LVS solubility enhancement in the presence of arginine (ARG) as a hydrotropic agent. The electrolytic conductance of LVS-ARG binary system was measured at temperatures from 298.15 K to 313.15 K. Conductometric parameters such as limiting molar conductance was evaluated. Additionally, thermodynamic parameters (ΔG0, ΔH0, ΔS0 and ES) involved in the association process of the solute in the aqueous solution of ARG solution were determined systematically. Solubility markedly improved 43-fold in the LVS-ARG complex compared to LVS alone. The analysed data from values of molar conductance and activation energy suggested favourable solubilisation, with a stronger solute-solvent interaction between LVS-ARG in water at higher temperatures. ARG and LVS complexation caused by strong molecular interactions was confirmed by spectral results. Hence, the addition of ARG as a co-solute was proven to enhance LVS solubility in water. The obtained data will ultimately enable the development of desired highly soluble, more efficient and safer LVS preparations.

Matched MeSH terms: Arginine/chemistry*; Lovastatin/chemistry*; Solvents/chemistry*
A review on the properties of electrospun cellulose acetate and its application in drug delivery systems: A new perspective

Wsoo MA, Shahir S, Mohd Bohari SP, Nayan NHM, Razak SIA

Carbohydr Res, 2020 May;491:107978.
PMID: 32163784 DOI: 10.1016/j.carres.2020.107978

Cellulose acetate (CA) is a remarkable biomaterial most extensively used in biomedical applications due to their properties. This review highlighted the synthesis and chemical structure of CA polymer as well as focused on the mechanical, chemical, thermal, biocompatible, and biodegradable properties of electrospun CA nanofibers. These properties are essential in the evaluation of the CA nanofibers and provide information as a reference for the further utilization and improvement of CA nanofibers. Moreover, we have summarized the use of electrospun CA nanofibers in the drug delivery system as a carrier for drugs and classify them according to the drug class, including anti-inflammatory, anticancer, antioxidant, antimicrobial agents, vitamins and amino acids. Our review has been concluded that CA nanofibers cannot wholly be biodegraded within the human body due to the absence of cellulase enzyme but degraded by microorganisms. Hence, the biodegradation of CA nanofibers in vivo has addressed as a critical challenge.

Matched MeSH terms: Amino Acids/chemistry; Anti-Infective Agents/chemistry; Anti-Inflammatory Agents/chemistry; Antineoplastic Agents/chemistry; Antioxidants/chemistry; Cellulose/chemistry; Vitamins/chemistry; Nanofibers/chemistry
DNA-templated silver nanocluster for live-intracellular FOXP3 detection

Lee SY, Fazlina N, Tye GJ

Anal Biochem, 2019 09 15;581:113352.
PMID: 31260647 DOI: 10.1016/j.ab.2019.113352

DNA-templated silver nanocluster (AgNC), a new promising fluorescence probe has gained importance in biosensing and bioimaging in recent years. We employed a label-free AgNC to detect an intracellular transcription factor known as forkhead box p3 (FOXP3), which is the master regulator of regulatory T cells (Tregs) suppressive function. We developed an optimized method for the detection of messenger ribonucleic acid (mRNA) of FOXP3 by hybridizing AgNC and G-rich to the target FOXP3 mRNA of a MCF-7 cells. MCF-7 cells are chosen as a model as it readily expresses FOXP3. The hybridized samples were examined with UV illuminator and further verified with fluorescence spectroscopy, fluorescence microscope and flow cytometry. The successful hybridization of a three-way junction with AgNC, G-rich and mRNA FOXP3 target generated an improved fluorescence intensity with a spectral shift. We have successfully delivered the green fluorescing AgNC and G-rich into MCF-7 cells, producing a shift to red fluorescing cells corroborated by flow cytometry results. In summary, our approach enables the detection of intracellular FOXP3 nucleic acid and holds considerable potential in establishing a non-lethal intracellular detection system which would be crucial for the isolation of regulatory T-cells (Tregs) when combined with other cell surface markers.

Matched MeSH terms: DNA/chemistry*; Silver/chemistry*; Metal Nanoparticles/chemistry*
Poly(lactic acid)-Mass production, processing, industrial applications, and end of life

Castro-Aguirre E, Iñiguez-Franco F, Samsudin H, Fang X, Auras R

Adv Drug Deliv Rev, 2016 12 15;107:333-366.
PMID: 27046295 DOI: 10.1016/j.addr.2016.03.010

Global awareness of material sustainability has increased the demand for bio-based polymers like poly(lactic acid) (PLA), which are seen as a desirable alternative to fossil-based polymers because they have less environmental impact. PLA is an aliphatic polyester, primarily produced by industrial polycondensation of lactic acid and/or ring-opening polymerization of lactide. Melt processing is the main technique used for mass production of PLA products for the medical, textile, plasticulture, and packaging industries. To fulfill additional desirable product properties and extend product use, PLA has been blended with other resins or compounded with different fillers such as fibers, and micro- and nanoparticles. This paper presents a review of the current status of PLA mass production, processing techniques and current applications, and also covers the methods to tailor PLA properties, the main PLA degradation reactions, PLA products' end-of-life scenarios and the environmental footprint of this unique polymer.

Matched MeSH terms: Polyesters/chemistry*; Lactic Acid/chemistry; Nanoparticles/chemistry
Comparison studies on the percolation thresholds of binary mixture tablets containing excipients of plastic/brittle and plastic/plastic deformation properties

Amin MC, Fell JT

Drug Dev Ind Pharm, 2004;30(9):937-45.
PMID: 15554218

Percolation theory has been used with great interest in understanding the design and characterization of dosage forms. In this study, work has been carried out to investigate the behavior of binary mixture tablets containing excipients of similar and different deformation properties. The binary mixture tablets were prepared by direct compression using lactose, polyvinyl chloride (PVC), Eudragit RS 100, and microcrystalline cellulose (MCC). The application of percolation theory on the relationships between compactibility, Pmax, or compression susceptibility (compressibility), gamma, and mixture compositions reveals the presence of percolation thresholds even for mixtures of similar deformation properties. The results showed that all mixture compositions exhibited at least one discreet change in the slope, which was referred to as the percolation threshold. The PVC/Eudragit RS100 mixture compositions showed significant percolation threshold at 80% (w/w) PVC loading. Two percolation thresholds were observed from a series of binary mixtures containing similar plastic deformation materials (PVC/MCC). The percolation thresholds were determined at 20% (w/w) and 80% (w/w) PVC loading. These are areas where one of the components percolates throughout the system and the properties of the tablets are expected to experience a sudden change. Experimental results, however, showed that total disruption of the tablet physical properties at the specified percolation thresholds can be observed for PVC/lactose mixtures at 20-30% (w/w) loading while only minor changes in the tablets' strength for PVC/MCC or PVC/Eudragit RS 100 mixtures were observed.

Matched MeSH terms: Acrylic Resins/chemistry; Cellulose/chemistry; Chemistry, Pharmaceutical; Chemistry, Physical; Excipients/chemistry*; Lactose/chemistry; Plastics/chemistry*; Polyvinyl Chloride/chemistry
Development and characterisation of packaging film from Napier cellulose nanowhisker reinforced polylactic acid (PLA) bionanocomposites

Sucinda EF, Abdul Majid MS, Ridzuan MJM, Cheng EM, Alshahrani HA, Mamat N

Int J Biol Macromol, 2021 Sep 30;187:43-53.
PMID: 34271052 DOI: 10.1016/j.ijbiomac.2021.07.069

A packaging material that is environment-friendly with excellent mechanical and physicochemical properties, biodegradable and ultraviolet (UV) protection and thermal stability was prepared to reduce plastic waste. Six different concentrations of Pennisetum purpureum/Napier cellulose nanowhiskers (NWCs) (i.e. 0, 0.5, 1.0, 1.5, 2.0, and 3.0 wt%) were used to reinforce polylactic acid (PLA) by a solvent casting method. The resulting bionanocomposite film samples were characterised in terms of their morphology, chemical structure, crystallinity, thermal degradation and stability, light transmittance, water absorption, biodegradability, and physical and mechanical properties. Field-emission scanning electron microscopy showed the excellent dispersion of NWC in the PLA matrix occurred with NWC concentrations of 0.5-1.5 wt%. All the bionanocomposite film samples exhibited good thermal stability at approximately 343-359 °C. The highest water absorption was 1.94%. The lowest transparency at λ800 was 16.16% for the PLA/3.0% NWC bionanocomposite film, which also has the lowest UVA and UVB transmittance of 7.49% and 4.02%, respectively, making it suitable for packaging materials. The PLA/1.0% NWC film exhibited the highest crystallinity of 50.09% and high tensile strength and tensile modulus of 21.22 MPa and 11.35 MPa, respectively.

Matched MeSH terms: Cellulose/chemistry*; Polyesters/chemistry*; Pennisetum/chemistry*
Hydrothermal synthesis of phosphorylated chitosan and its adsorption performance towards Acid Red 88 dye

Subramaniam S, Foo KY, Md Yusof EN, Jawad AH, Wilson LD, Sabar S

Int J Biol Macromol, 2021 Dec 15;193(Pt B):1716-1726.
PMID: 34742842 DOI: 10.1016/j.ijbiomac.2021.11.009

Phosphorylated chitosan (P-CS) was successfully synthesized using a facile experimental setup of hydrothermal method that was applied to the adsorption of anionic Acid Red 88 (AR88) from aqueous media. The adsorption process obeyed the pseudo-second-order (PSO) kinetic model. In contrast, the adsorption isotherm conformed to the Langmuir model, with the maximum adsorption capacity (qm = 230 mg g-1) at 303 K. Both external and intraparticle diffusion strongly influenced the rate of adsorption. The insights from this study reveal that P-CS could be easily prepared and regenerated for reusability applications. The adsorption mechanism and intermolecular interaction between P-CS and AR 88 were investigated using Fourier transform infrared (FTIR) spectroscopy and calculations via Density Functional Theory (DFT). The key modes of adsorption for the P-CS/AR 88 system are driven by electrostatic attractions, H-bonding, and n-π interactions. The findings herein reveal that P-CS is a promising adsorbent for the removal of anionic dyes such as AR88 or similar pollutants from water.

Matched MeSH terms: Azo Compounds/chemistry*; Coloring Agents/chemistry*; Chitosan/chemistry*
Fulltext A comprehensive review on the techniques for coconut oil extraction and its application

Ng YJ, Tham PE, Khoo KS, Cheng CK, Chew KW, Show PL

Bioprocess Biosyst Eng, 2021 Sep;44(9):1807-1818.
PMID: 34009462 DOI: 10.1007/s00449-021-02577-9

Virgin coconut oil is a useful substance in our daily life. It contains a high percentage of lauric acid which has many health benefits. The current industry has developed several methods to extract the oil out from the coconut fruit. This review paper aims to highlight several common extraction processes used in modern industries that includes cold extraction, hot extraction, low-pressure extraction, chilling, freezing and thawing method, fermentation, centrifugation, enzymatic extraction and supercritical fluid carbon dioxide. Different extraction methods will produce coconut oil with different yields and purities of lauric acid, thus having different uses and applications. Challenges that are faced by the industries in extracting the coconut oil using different methods of extraction are important to be explored so that advancement in the oil extraction technology can be done for efficient downstream processing. This study is vital as it provides insights that could enhance the production of coconut oil.

Matched MeSH terms: Cocos/chemistry*; Fruit/chemistry*; Lauric Acids/chemistry*
Lignans from barks of Hernandia nymphaefolia and H. peltata

Rahmani M, Toia RF, Croft KD

Planta Med, 1995 Oct;61(5):487-8.
PMID: 7480216
Matched MeSH terms: Plants, Medicinal/chemistry*; Trees/chemistry*; Lignans/chemistry

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