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Isolation and characterization of the major phospholipase A2 from the venom of Trimeresurus purpureomaculatus (shore pit viper)

Nget Hong Tan, Chon Seng Tan, Hun Teck Khor

Int. J. Biochem., 1989;21(12):1421-6.
PMID: 2612728

1. The major phospholipase A2 (PLA-DE4) of the venom of Trimeresurus purpureomaculatus (shore pit viper) has been purified to electrophoretic homogeneity. 2. The isoelectric point of the purified enzyme was determined to be 4.20, and the mol. wt was 31,700 as estimated by Sephadex G-75 gel filtration chromatography; and 14,000 as estimated by SDS-polyacrylamide gel electrophoresis. The purified enzyme hydrolyzed phosphatidylcholine (PC) faster than phosphatidylethanolamine (PE), whereas phosphatidylserine (PS) was not hydrolyzed at all (PC greater than PE greater than PS =0). However, in reaction system consisted of mixtures of PC and PS, phosphatidylserine was effectively hydrolyzed by the enzyme. 4. The phospholipase A2 exhibited edema-forming activity but not hemolytic, hemorrhagic or anticoagulant activities. It was not lethal to mice at a dosage of 10 micrograms/g by i.v. route.

Matched MeSH terms: Chromatography, DEAE-Cellulose
Oral 5-fluorouracil colon-specific delivery through in vivo pellet coating for colon cancer and aberrant crypt foci treatment

Bose A, Elyagoby A, Wong TW

Int J Pharm, 2014 Jul 1;468(1-2):178-86.
PMID: 24709212 DOI: 10.1016/j.ijpharm.2014.04.006

In situ coating of 5-fluorouracil pellets by ethylcellulose and pectin powder mixture (8:3 weight ratio) in capsule at simulated gastrointestinal media provides colon-specific drug release in vitro. This study probes into pharmacodynamic and pharmacokinetic profiles of intra-capsular pellets coated in vivo in rats with reference to their site-specific drug release outcomes. The pellets were prepared by extrusion-spheronization technique. In vitro drug content, drug release, in vivo pharmacokinetics, local colonic drug content, tumor, aberrant crypt foci, systemic hematology and clinical chemistry profiles of coated and uncoated pellets were examined against unprocessed drug. In vivo pellet coating led to reduced drug bioavailability and enhanced drug accumulation at colon (179.13 μg 5-FU/g rat colon content vs 4.66 μg/g of conventional in vitro film-coated pellets at 15 mg/kg dose). The in vivo coated pellets reduced tumor number and size, through reforming tubular epithelium with basement membrane and restricting expression of cancer from adenoma to adenocarcinoma. Unlike uncoated pellets and unprocessed drug, the coated pellets eliminated aberrant crypt foci which represented a putative preneoplastic lesion in colon cancer. They did not inflict additional systemic toxicity. In vivo pellet coating to orally target 5-fluorouracil delivery at cancerous colon is a feasible therapeutic treatment approach.

Matched MeSH terms: Cellulose/analogs & derivatives; Cellulose/chemistry
Homozygous state for Hb Constant Spring (slow-moving Hb X components)

Lie-Injo LE, Ganesan J, Clegg JB, Weatherall DJ

Blood, 1974 Feb;43(2):251-9.
PMID: 4810076
Matched MeSH terms: Cellulose
Genetic studies of water buffalo blood markers. II. Carbonic anhydrase, esterase D, malate dehydrogenase, and malic enzyme

Sreetharan K, Mukherjee TK, Tan SG, Selvaraj OS, Barker JS

Biochem Genet, 1994 Feb;32(1-2):35-8.
PMID: 8031293
Matched MeSH terms: Electrophoresis, Cellulose Acetate
Caseinolytic and esteratic activities of Malayan pit viper venom and its proteolytic and thrombin-like fractions

Soh KS, Chan KE

Toxicon, 1974 Mar;12(2):151-8.
PMID: 4859238
Matched MeSH terms: Chromatography, DEAE-Cellulose
Inheritance of haemoglobin H disease. A new aspect

Lie-Injo LE, Lopez CG, Lopes M

Acta Haematol., 1971;46(2):106-20.
PMID: 4331171 DOI: 10.1159/000208565

A study of 23 patients with Hb H disease and their 82 relatives in 17 families showed that 2 types of this condition exist. One is associated with the presence of a small slow-moving component, which we tentatively called the X component and which was invariably present in one parent. Some siblings also had it. The other type was not associated with this component. Two patients without X component had a newborn with Bart’s haemoglobin without X component. None of the parents of 20 newborns with Hb Bart’s without the X component had the X component. It was present in only one parent of each of 2 newborns with Hb Bart’s and the X component. They are thought to represent Hb H disease in the newborn period. We suggest that at least 3 abnormal genes may lead to Hb H disease, which results when 2 of the 3 combine. Severity of clinical and haematological symptoms depends upon which abnormal gene is present and which 2 are involved in any particular combination.
Key Words: a-Thalassaemia; Haemoglobin Bart’s; Haemoglobin H disease; Haemoglobinopathies

Matched MeSH terms: Chromatography, DEAE-Cellulose
Structural identification of haemoglobin F Kuala Lumpur: alpha2 gamma2 22(B4)Asp leads to Gly; 136 Ala

Luan Eng LI, Wiltshire BG, Lehmann H

Biochim. Biophys. Acta, 1973 Oct 18;322(2):224-30.
PMID: 4765089
Matched MeSH terms: Cellulose
Fulltext The impact of oligofructose on stimulation of gut hormones, appetite regulation and adiposity

Daud NM, Ismail NA, Thomas EL, Fitzpatrick JA, Bell JD, Swann JR, et al.

Obesity (Silver Spring), 2014 Jun;22(6):1430-8.
PMID: 24715424 DOI: 10.1002/oby.20754

OBJECTIVE: To investigate the effect of nutrient stimulation of gut hormones by oligofructose supplementation on appetite, energy intake (EI), body weight (BW) and adiposity in overweight and obese volunteers.
METHODS: In a parallel, single-blind and placebo-controlled study, 22 healthy overweight and obese volunteers were randomly allocated to receive 30 g day(-1) oligofructose or cellulose for 6 weeks following a 2-week run-in. Subjective appetite and side effect scores, breath hydrogen, serum short chain fatty acids (SCFAs), plasma gut hormones, glucose and insulin concentrations, EI, BW and adiposity were quantified at baseline and post-supplementation.
RESULTS: Oligofructose increased breath hydrogen (P

Matched MeSH terms: Cellulose/administration & dosage
Fulltext Preparation and properties of poly(vinyl alcohol)/chitosan blend bionanocomposites reinforced with cellulose nanocrystals/ZnO-Ag multifunctional nanosized filler

Azizi S, Ahmad MB, Hussein MZ, Ibrahim NA, Namvar F

Int J Nanomedicine, 2014;9:1909-17.
PMID: 24790433 DOI: 10.2147/IJN.S60274

A series of novel bionanocomposites were cast using different contents of zinc oxide-silver nanoparticles (ZnO-AgNPs) stabilized by cellulose nanocrystals (CNC) as multifunctional nanosized fillers in poly(vinyl alcohol)/chitosan (PVA/Cs) matrices. The morphological structure, mechanical properties, ultraviolet-visible absorption, and antimicrobial properties of the prepared films were investigated as a function of their CNC/ZnO-AgNP content and compared with PVA/chitosan/CNC bionanocomposite films. X-ray diffraction and field emission scanning electron microscopic analyses showed that the CNC/ZnO-AgNPs were homogeneously dispersed in the PVA/Cs matrix and the crystallinity increased with increasing nanosized filler content. Compared with pure PVA/Cs, the tensile strength and modulus in the films increased from 0.055 to 0.205 GPa and from 0.395 to 1.20 GPa, respectively. Ultraviolet and visible light can be efficiently absorbed by incorporating ZnO-AgNPs into a PVA/Cs matrix, suggesting that these bionanocomposite films show good visibility and ultraviolet-shielding effects. The bionanocomposite films had excellent antimicrobial properties, killing both Gram-negative Salmonella choleraesuis and Gram-positive Staphylococcus aureus. The enhanced physical properties achieved by incorporating CNC/ZnO-AgNPs could be beneficial in various applications.

Matched MeSH terms: Cellulose/chemistry*
A simple microextraction and preconcentration approach based on a mixed matrix membrane

Kamaruzaman S, Hauser PC, Sanagi MM, Ibrahim WA, Endud S, See HH

Anal Chim Acta, 2013 Jun 14;783:24-30.
PMID: 23726096 DOI: 10.1016/j.aca.2013.04.042

A simple adsorption/desorption procedure using a mixed matrix membrane (MMM) as extraction medium is demonstrated as a new miniaturized sample pretreatment and preconcentration technique. Reversed-phase particles namely polymeric bonded octadecyl (C18) was incorporated through dispersion in a cellulose triacetate (CTA) polymer matrix to form a C18-MMM. Non-steroidal anti-inflammatory drugs (NSAIDs) namely diclofenac, mefenamic acid and ibuprofen present in the environmental water samples were selected as targeted model analytes. The extraction setup is simple by dipping a small piece of C18-MMM (7 mm × 7 mm) in a stirred 10 mL sample solution for analyte adsorption process. The entrapped analyte within the membrane was then desorbed into 100 μL of methanol by ultrasonication prior to high performance liquid chromatography (HPLC) analysis. Each membrane was discarded after single use to avoid any analyte carry-over effect. Several important parameters, such as effect of sample pH, salting-out effect, sample volume, extraction time, desorption solvent and desorption time were comprehensively optimized. The C18-MMM demonstrated high affinity for NSAIDs spiked in tap and river water with relative recoveries ranging from 92 to 100% and good reproducibility with relative standard deviations between 1.1 and 5.5% (n=9). The overall results obtained were found comparable against conventional solid phase extraction (SPE) using cartridge packed with identical C18 adsorbent.

Matched MeSH terms: Cellulose
Micromechanical modelling of oil palm empty fruit bunch fibres containing silica bodies

Omar FN, Hanipah SH, Xiang LY, Mohammed MAP, Baharuddin AS, Abdullah J

J Mech Behav Biomed Mater, 2016 09;62:106-118.
PMID: 27183430 DOI: 10.1016/j.jmbbm.2016.04.043

Experimental and numerical investigation was conducted to study the micromechanics of oil palm empty fruit bunch fibres containing silica bodies. The finite viscoelastic-plastic material model called Parallel Rheological Network model was proposed, that fitted well with cyclic and stress relaxation tensile tests of the fibres. Representative volume element and microstructure models were developed using finite element method, where the models information was obtained from microscopy and X-ray micro-tomography analyses. Simulation results showed that difference of the fibres model with silica bodies and those without ones is larger under shear than compression and tension. However, in comparison to geometrical effect (i.e. silica bodies), it is suggested that ultrastructure components of the fibres (modelled using finite viscoelastic-plastic model) is responsible for the complex mechanical behaviour of oil palm fibres. This can be due to cellulose, hemicellulose and lignin components and the interface behaviour, as reported on other lignocellulosic materials.

Matched MeSH terms: Cellulose
Haemoglobin F Malaysia: alpha 2, gamma 2 1(NA1) glycine--cysteine; 136 glycine

Eng LI, Kamuzora H, Lehmann H

J Med Genet, 1974 Mar;11(1):25-30.
PMID: 4837284
Matched MeSH terms: Chromatography, DEAE-Cellulose
Fulltext Structural, Morphological and Thermal Properties of Cellulose Nanofibers from Napier fiber (Pennisetum purpureum)

Radakisnin R, Abdul Majid MS, Jamir MRM, Jawaid M, Sultan MTH, Mat Tahir MF

Materials (Basel), 2020 Sep 17;13(18).
PMID: 32957438 DOI: 10.3390/ma13184125

The purpose of the study is to investigate the utilisation of Napier fiber (Pennisetum purpureum) as a source for the fabrication of cellulose nanofibers (CNF). In this study, cellulose nanofibers (CNF) from Napier fiber were isolated via ball-milling assisted by acid hydrolysis. Acid hydrolysis with different molarities (1.0, 3.8 and 5.6 M) was performed efficiently facilitate cellulose fiber size reduction. The resulting CNFs were characterised through Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), particle size analyser (PSA), field-emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The FTIR results demonstrated that there were no obvious changes observed between the spectra of the CNFs with different molarities of acid hydrolysis. With 5.6 M acid hydrolysis, the XRD analysis displayed the highest degree of CNF crystallinity at 70.67%. In a thermal analysis by TGA and DTG, cellulose nanofiber with 5.6 M acid hydrolysis tended to produce cellulose nanofibers with higher thermal stability. As evidenced by the structural morphologies, a fibrous network nanostructure was obtained under TEM and AFM analysis, while a compact structure was observed under FESEM analysis. In conclusion, the isolated CNFs from Napier-derived cellulose are expected to yield potential to be used as a suitable source for nanocomposite production in various applications, including pharmaceutical, food packaging and biomedical fields.

Matched MeSH terms: Cellulose
Fulltext A highly thermostable crude endoglucanase produced by a newly isolated Thermobifida fusca strain UPMC 901

Zainudin MHM, Mustapha NA, Hassan MA, Bahrin EK, Tokura M, Yasueda H, et al.

Sci Rep, 2019 09 19;9(1):13526.
PMID: 31537863 DOI: 10.1038/s41598-019-50126-y

A thermophilic Thermobifida fusca strain UPMC 901, harboring highly thermostable cellulolytic activity, was successfully isolated from oil palm empty fruit bunch compost. Its endoglucanase had the highest activity at 24 hours of incubation in carboxymethyl-cellulose (CMC) and filter paper. A maximum endoglucanase activity of 0.9 U/mL was achieved at pH 5 and 60 °C using CMC as a carbon source. The endoglucanase properties were further characterized using crude enzyme preparations from the culture supernatant. Thermal stability indicated that the endoglucanase activity was highly stable at 70 °C for 24 hours. Furthermore, the activity was found to be completely maintained without any loss at 50 °C and 60 °C for 144 hours, making it the most stable than other endoglucanases reported in the literature. The high stability of the endoglucanase at an elevated temperature for a prolonged period of time makes it a suitable candidate for the biorefinery application.

Matched MeSH terms: Carboxymethylcellulose Sodium; Cellulose
Fulltext Subcritical Water-Carbon Dioxide Pretreatment of Oil Palm Mesocarp Fiber for Xylooligosaccharide and Glucose Production

Ahmad N, Zakaria MR, Mohd Yusoff MZ, Fujimoto S, Inoue H, Ariffin H, et al.

Molecules, 2018 May 30;23(6).
PMID: 29848973 DOI: 10.3390/molecules23061310

The present work aimed to investigate the pretreatment of oil palm mesocarp fiber (OPMF) in subcritical H₂O-CO₂ at a temperature range from 150⁻200 °C and 20⁻180 min with CO₂ pressure from 3⁻5 MPa. The pretreated solids and liquids from this process were separated by filtration and characterized. Xylooligosaccharides (XOs), sugar monomers, acids, furans and phenols in the pretreated liquids were analyzed by using HPLC. XOs with a degree of polymerization X2⁻X4 comprising xylobiose, xylotriose, xylotetraose were analyzed by using HPAEC-PAD. Enzymatic hydrolysis was performed on cellulose-rich pretreated solids to observe xylose and glucose production. An optimal condition for XOs production was achieved at 180 °C, 60 min, 3 MPa and the highest XOs obtained was 81.60 mg/g which corresponded to 36.59% of XOs yield from total xylan of OPMF. The highest xylose and glucose yields obtained from pretreated solids were 29.96% and 84.65%, respectively at cellulase loading of 10 FPU/g-substrate.

Matched MeSH terms: Cellulose
Fulltext Carbamazepine Gel Formulation as a Sustained Release Epilepsy Medication for Pediatric Use

Mawazi SM, Al-Mahmood SMA, Chatterjee B, Hadi HA, Doolaanea AA

Pharmaceutics, 2019 Sep 20;11(10).
PMID: 31547112 DOI: 10.3390/pharmaceutics11100488

This study aimed to develop a carbamazepine (CBZ) sustained release formulation suitable for pediatric use with a lower risk of precipitation. The CBZ was first prepared as sustained release microparticles, and then the microparticles were embedded in alginate beads, and finally, the beads were suspended in a gel vehicle. The microparticles were prepared by a solvent evaporation method utilizing ethyl cellulose as a sustained release polymer and were evaluated for particle size, encapsulation efficiency, and release profile. The beads were fabricated by the dropwise addition of sodium alginate in calcium chloride solution and characterized for size, shape, and release properties. The gel was prepared using iota carrageenan as the gelling agent and evaluated for appearance, syneresis, drug content uniformity, rheology, release profile, and stability. The microparticles exhibited a particle size of 135.01 ± 0.61 µm with a monodisperse distribution and an encapsulation efficiency of 83.89 ± 3.98%. The beads were monodispersed with an average size of 1.4 ± 0.05 mm and a sphericity factor of less than 0.05. The gel was prepared using a 1:1 ratio (gel vehicle to beads) and exhibited no syneresis, good homogeneity, and good shear-thinning properties. The release profile from the beads and from the gel was not significantly affected, maintaining similarity to the tablet form. The gel properties were maintained for one month real time stability, but the accelerated stability showed reduced viscosity and pH with time. In conclusion, CBZ in a gel sustained release dosage form combines the advantages of the suspension form in terms of dosing flexibility, and the advantages of the tablet form in regards to the sustained release profile. This dosage form should be further investigated in vivo in animal models before being considered in clinical trials.

Matched MeSH terms: Cellulose
Fulltext Extraction and Characterization of Potential Biodegradable Materials Based on Dioscorea hispida Tubers

Hazrati KZ, Sapuan SM, Zuhri MYM, Jumaidin R

Polymers (Basel), 2021 Feb 15;13(4).
PMID: 33672030 DOI: 10.3390/polym13040584

This study was driven by the stringent environmental legislation concerning the consumption and utilization of eco-friendly materials. Within this context, this paper aimed to examine the characteristics of starch and fibres from the Dioscorea hispida tuber plant to explore their potential as renewable materials. The extraction of the Dioscorea hispida starch and Dioscorea hispida fibres was carried out and the chemical composition, physical, thermal, morphological properties, and crystallinity were studied. The chemical composition investigations revealed that the Dioscorea hispida starch (DHS) has a low moisture t (9.45%) and starch content (37.62%) compared to cassava, corn, sugar palm, and arrowroot starches. Meanwhile, the Dioscorea hispida fibres (DHF) are significantly low in hemicellulose (4.36%), cellulose (5.63%), and lignin (2.79%) compared to cassava, corn hull and sugar palm. In this investigation the chemical, physical, morphological and thermal properties of the Dioscorea hispida fibre and Dioscorea hispida starch were examined by chemical composition investigation, scanning electron microscopy (SEM), particle size distribution, thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), and Fourier transform infrared (FTIR), respectively. It was found that Dioscorea hispida waste is promising alternative biomass and sustainable material with excellent potential as a renewable filler material for food packaging applications.

Matched MeSH terms: Cellulose
Fulltext Recycling Waste Cotton Cloths for the Isolation of Cellulose Nanocrystals: A Sustainable Approach

Mohamed SH, Hossain MS, Mohamad Kassim MH, Ahmad MI, Omar FM, Balakrishnan V, et al.

Polymers (Basel), 2021 Feb 19;13(4).
PMID: 33669623 DOI: 10.3390/polym13040626

There is an interest in the sustainable utilization of waste cotton cloths because of their enormous volume of generation and high cellulose content. Waste cotton cloths generated are disposed of in a landfill, which causes environmental pollution and leads to the waste of useful resources. In the present study, cellulose nanocrystals (CNCs) were isolated from waste cotton cloths collected from a landfill. The waste cotton cloths collected from the landfill were sterilized and cleaned using supercritical CO2 (scCO2) technology. The cellulose was extracted from scCO2-treated waste cotton cloths using alkaline pulping and bleaching processes. Subsequently, the CNCs were isolated using the H2SO4 hydrolysis of cellulose. The isolated CNCs were analyzed to determine the morphological, chemical, thermal, and physical properties with various analytical methods, including attenuated total reflection-Fourier transform-infrared spectroscopy (ATR-FTIR), field-emission scanning electron microscopy (FE-SEM), energy-filtered transmission electron microscopy (EF-TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The results showed that the isolated CNCs had a needle-like structure with a length and diameter of 10-30 and 2-6 nm, respectively, and an aspect ratio of 5-15, respectively. Additionally, the isolated CNCs had a high crystallinity index with a good thermal stability. The findings of the present study revealed the potential of recycling waste cotton cloths to produce a value-added product.

Matched MeSH terms: Cellulose
Fulltext Highly Active Cellulose-Supported Poly(hydroxamic acid)-Cu(II) Complex for Ullmann Etherification

Jian Fui C, Xin Ting T, Sarjadi MS, Amin Z, Sarkar SM, Musta B, et al.

ACS Omega, 2021 Mar 16;6(10):6766-6779.
PMID: 33748590 DOI: 10.1021/acsomega.0c05840

Highly active natural pandanus-extracted cellulose-supported poly(hydroxamic acid)-Cu(II) complex 4 was synthesized. The surface of pandanus cellulose was modified through graft copolymerization using purified methyl acrylate as a monomer. Then, copolymer methyl acrylate was converted into a bidentate chelating ligand poly(hydroxamic acid) via a Loosen rearrangement in the presence of an aqueous solution of hydroxylamine. Finally, copper species were incorporated into poly(hydroxamic acid) via the adsorption process. Cu(II) complex 4 was fully characterized by Fourier transform infrared (FTIR), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX), transmission electron microscopy (TEM), inductively coupled plasma optical emission spectrometry (ICP-OES), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses. The cellulose-supported Cu(II) complex 4 was successfully applied (0.005 mol %) to the Ullmann etherification of aryl, benzyl halides, and phenacyl bromide with a number of aromatic phenols to provide the corresponding ethers with excellent yield [benzyl halide (70-99%); aryl halide (20-90%)]. Cu(II) complex 4 showed high stability and was easily recovered from the reaction mixture. It could be reused up to seven times without loss of its original catalytic activity. Therefore, Cu(II) complex 4 can be commercially utilized for the preparation of various ethers, and this synthetic technique could be a part in the synthesis of natural products and medicinal compounds.

Matched MeSH terms: Cellulose
Fulltext The effect of Palm Oil Mill Effluent Final Discharge on the Characteristics of Pennisetum purpureum

Osman NA, Ujang FA, Roslan AM, Ibrahim MF, Hassan MA

Sci Rep, 2020 04 20;10(1):6613.
PMID: 32313095 DOI: 10.1038/s41598-020-62815-0

Phytoremediation is one of the environmental-friendly and cost-effective systems for the treatment of wastewater, including industrial wastewater such as palm oil mill effluent final discharge (POME FD). However, the effects of the wastewater on the phytoremediator plants, in term of growth performance, lignocellulosic composition, and the presence of nutrients and heavy metals in the plants are not yet well studied. In the present work, we demonstrated that POME FD increased the growth of P. purpureum. The height increment of P. purpureum supplied with POME FD (treatment) was 61.72% as compared to those supplied with rain water (control) which was 14.42%. For lignocellulosic composition, the cellulose percentages were 38.77 ± 0.29% (treatment) and 34.16 ± 1.01% (control), and the difference was significant. These results indicated that POME FD could be a source of plant nutrients, which P. purpureum can absorb for growth. It was also found that the heavy metals (Al, As, Cd, Co, Cr, Ni and Pb) inside the plant were below the standard limit of the World Health Organization (WHO). Since POME FD was shown to have no adverse effects on P. purpureum, further research regarding the potential application of P. purpureum following phytoremediation of POME FD such as biofuel production is warranted to evaluate its potential use to fit into the waste-to-wealth agenda.

Matched MeSH terms: Cellulose

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