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Kigelia africana (Lam.) Benth. (Sausage tree): Phytochemistry and pharmacological review of a quintessential African traditional medicinal plant

Bello I, Shehu MW, Musa M, Zaini Asmawi M, Mahmud R

J Ethnopharmacol, 2016 Aug 02;189:253-76.
PMID: 27220655 DOI: 10.1016/j.jep.2016.05.049

ETHNOPHARMACOLOGICAL RELEVANCE: Kigelia africana is a quintessential African herbal medicinal plant with a pan-African distribution and immense indigenous medicinal and non-medicinal applications. The plant is use traditionally as a remedy for numerous disease such as use wounds healing, rheumatism, psoriasis, diarrhea and stomach ailments. It is also use as an aphrodisiac and for skin care.
AIM OF THE REVIEW: The present review aims to compile an up-to-date review of the progress made in the continuous pharmacological and phytochemistry investigation of K. africana and the corresponding commercial and pharmaceutical application of these findings with the ultimate objective of providing a guide for future research on this plant.
METHOD: The scholarly information needed for this paper were predominantly sourced from the electronic search engines such as Google, Google scholar; publishing sites such as Elsevier, scienceDirect, BMC, PubMed; other scientific database sites for chemicals such as ChemSpider, PubChem, and also from online books.
RESULTS: Pharmacological investigations conducted confirm the anti-inflammatory, analgesic, antioxidant and anticancer activity of the extract of different parts of the plant. Bioactive constituents are found to be present in all parts of the plant. So far, approximately 150 compounds have been characterized from different part of the plant. Iridoids, naphthoquinones, flavonoids, terpenes and phenylethanoglycosides are the major class of compounds isolated. Novel compounds with potent antioxidant, antimicrobial and anticancer effect such as verbascoside, verminoside and pinnatal among others, have been identified. Commercial trade of K. africana has boosted in the las few decades. Its effect in the maintenance of skin has been recognized resulting in a handful of skin formulations in the market.
CONCLUSIONS: The pharmaceutical potentials of K. africana has been recognized and have witness a surge in research interest. However, till date, many of its traditional medicinal uses has not been investigated scientifically. Further probing of the existential researches on its pharmacological activity is recommended with the end-goal of unravelling the pharmacodynamics, pharmacokinetics, clinical relevance and possible toxicity and side effects of both the extract and the active ingredients isolated.

Matched MeSH terms: Plant Extracts/chemistry; Bignoniaceae/chemistry*; Phytochemicals/chemistry
Immunomodulation in Middle-Aged Humans Via the Ingestion of Physta® Standardized Root Water Extract of Eurycoma longifolia Jack--A Randomized, Double-Blind, Placebo-Controlled, Parallel Study

George A, Suzuki N, Abas AB, Mohri K, Utsuyama M, Hirokawa K, et al.

Phytother Res, 2016 Apr;30(4):627-35.
PMID: 26816234 DOI: 10.1002/ptr.5571

This study was aimed to investigate the capacity of a standardized root water extract of Eurycoma longifolia (Tongkat Ali, TA), Physta® to modulate human immunity in a middle-aged Japanese population. This randomized, double-blind, placebo-controlled, parallel study was conducted for 4 weeks. Eighty-four of 126 subjects had relatively lower scores according to Scoring of Immunological Vigor (SIV) screening. Subjects were instructed to ingest either 200 mg/day of TA or rice powder as a placebo for 4 weeks [TA and Placebo (P) groups] and to visit a clinic in Tokyo twice (weeks 0 and 4). SIV, immunological grade, immunological age, and other immune parameters were measured. Eighty-three subjects completed the study; 40 in the TA group and 41 in the P group were statistically analyzed, whereas two were excluded from the analyses. At week 4, the SIV and immunological grade were significantly higher in the TA group than those in P group (p

Matched MeSH terms: Water/chemistry; Plant Roots/chemistry; Eurycoma/chemistry*
Preparation, characterization, and in vitro release studies of insulin-loaded double-walled poly(lactide-co-glycolide) microspheres

Ansary RH, Rahman MM, Awang MB, Katas H, Hadi H, Doolaanea AA

Drug Deliv Transl Res, 2016 06;6(3):308-18.
PMID: 26817478 DOI: 10.1007/s13346-016-0278-y

The purpose of this study was to fabricate insulin-loaded double-walled and single-polymer poly(lactide-co-glycolide) (PLGA) microspheres using a fast degrading glucose core, hydroxyl-terminated poly(lactide-co-glycolide) (Glu-PLGA), and a moderate degrading carboxyl-terminated PLGA polymers. A modified water-in-oil-in-oil-in-water (w/o/o/w) emulsion solvent evaporation technique was employed to prepare double-walled microspheres, whereas single-polymer microspheres were fabricated by a conventional water-in-oil-in-water (w/o/w) emulsion solvent evaporation method. The effect of fabrication techniques and polymer characteristics on microspheres size, morphology, encapsulation efficiency, in vitro release, and insulin stability was evaluated. The prepared double-walled microspheres were essentially non-porous, smooth surfaced, and spherical in shape, whereas single-polymer microspheres were highly porous. Double-walled microspheres exhibited a significantly reduced initial burst followed by sustained and almost complete release of insulin compared to single-polymer microspheres. Initial burst release was further suppressed from double-walled microspheres when the mass ratio of the component polymers was increased. In conclusion, double-walled microspheres made of Glu-PLGA and PLGA can be a potential delivery system of therapeutic insulin.

Matched MeSH terms: Glucose/chemistry; Insulin/chemistry; Polyglactin 910/chemistry*
On-Demand Guided Bone Regeneration with Microbial Protection of Ornamented SPU Scaffold with Bismuth-Doped Single Crystalline Hydroxyapatite: Augmentation and Cartilage Formation

Selvakumar M, Srivastava P, Pawar HS, Francis NK, Das B, Sathishkumar G, et al.

ACS Appl Mater Interfaces, 2016 Feb 17;8(6):4086-100.
PMID: 26799576 DOI: 10.1021/acsami.5b11723

Guided bone regeneration (GBR) scaffolds are futile in many clinical applications due to infection problems. In this work, we fabricated GBR with an anti-infective scaffold by ornamenting 2D single crystalline bismuth-doped nanohydroxyapatite (Bi-nHA) rods onto segmented polyurethane (SPU). Bi-nHA with high aspect ratio was prepared without any templates. Subsequently, it was introduced into an unprecedented synthesized SPU matrix based on dual soft segments (PCL-b-PDMS) of poly(ε-caprolactone) (PCL) and poly(dimethylsiloxane) (PDMS), by an in situ technique followed by electrospinning to fabricate scaffolds. For comparison, undoped pristine nHA rods were also ornamented into it. The enzymatic ring-opening polymerization technique was adapted to synthesize soft segments of PCL-b-PDMS copolymers of SPU. Structure elucidation of the synthesized polymers is done by nuclear magnetic resonance spectroscopy. Sparingly, Bi-nHA ornamented scaffolds exhibit tremendous improvement (155%) in the mechanical properties with excellent antimicrobial activity against various human pathogens. After confirmation of high osteoconductivity, improved biodegradation, and excellent biocompatibility against osteoblast cells (in vitro), the scaffolds were implanted in rabbits by subcutaneous and intraosseous (tibial) sites. Various histological sections reveal the signatures of early cartilage formation, endochondral ossification, and rapid bone healing at 4 weeks of the critical defects filled with ornamented scaffold compared to SPU scaffold. This implies osteogenic potential and ability to provide an adequate biomimetic microenvironment for mineralization for GBR of the scaffolds. Organ toxicity studies further confirm that no tissue architecture abnormalities were observed in hepatic, cardiac, and renal tissue sections. This finding manifests the feasibility of fabricating a mechanically adequate nanofibrous SPU scaffold by a biomimetic strategy and the advantages of Bi-nHA ornamentation in promoting osteoblast phenotype progression with microbial protection (on-demand) for GBR applications.

Matched MeSH terms: Dimethylpolysiloxanes/chemistry; Polyesters/chemistry; Tissue Scaffolds/chemistry*
Synthesis and characterization of a new vertebroplasty cement based on gold-containing PMMA microspheres

Jacobs E, Saralidze K, Roth AK, de Jong JJ, van den Bergh JP, Lataster A, et al.

Biomaterials, 2016 Mar;82:60-70.
PMID: 26751820 DOI: 10.1016/j.biomaterials.2015.12.024

There are a number of drawbacks to incorporating large concentrations of barium sulfate (BaSO4) as the radiopacifier in PMMA-based bone cements for percutaneous vertebroplasty. These include adverse effects on injectability, viscosity profile, setting time, mechanical properties of the cement and bone resorption. We have synthesized a novel cement that is designed to address some of these drawbacks. Its powder includes PMMA microspheres in which gold particles are embedded and its monomer is the same as that used in commercial cements for vertebroplasty. In comparison to one such commercial cement brand, VertaPlex™, the new cement has longer doughing time, longer injection time, higher compressive strength, higher compressive modulus, and is superior in terms of cytotoxicity. For augmentation of fractured fresh-frozen cadaveric vertebral bodies (T6-L5) using simulated vertebroplasty, results for compressive strength and compressive stiffness of the construct and the percentage of the volume of the vertebral body filled by the cement were comparable for the two cements although the radiopacity of the new cement was significantly lower than that for VertaPlex™. The present results indicate that the new cement warrants further study.

Matched MeSH terms: Barium Sulfate/chemistry*; Gold/chemistry*; Polymethyl Methacrylate/chemistry*
Fulltext Conjugated Oligo-Aromatic Compounds Bearing a 3,4,5-Trimethoxy Moiety: Investigation of Their Antioxidant Activity Correlated with a DFT Study

Kareem HS, Nordin N, Heidelberg T, Abdul-Aziz A, Ariffin A

Molecules, 2016 Feb 17;21(2).
PMID: 26901175 DOI: 10.3390/molecules21020224

A series of heterocyclic compounds bearing the well-known free radical scavenging 3,4,5-trimethoxybenzyloxy group, was synthesized. The key compound 4-(3,4,5-trimethoxybenzyl-oxy)benzohydrazide was converted into thiosemicarbazide derivatives, which were subsequently cyclized with NaOH to provide 1,2,4-triazole derivatives. Alternative treatment of the acid hydrazide with carbon disulfide in the presence of KOH led to the corresponding 1,3,4-oxadiazole and various alkylated derivatives. The newly synthesized compounds were purified and the structures of the products were elucidated and confirmed on the basis of their analytical and spectral data. Their antioxidant activities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH(•)) and Ferric Reducing Antioxidant Power (FRAP) assays. The thiosemicarbazide derivatives were highly active in both antioxidant assays with the lowest IC50 value for DPPH radical scavenging. Theoretical calculations based on density functional theory (DFT) were performed to understand the relative importance of NH, SH and CH hydrogens on the radical scavenging activities of these compounds.

Matched MeSH terms: Antioxidants/chemistry; Semicarbazides/chemistry*; Triazoles/chemistry
Medicinal and cosmetics soap production from Jatropha oil

Shahinuzzaman M, Yaakob Z, Moniruzzaman M

J Cosmet Dermatol, 2016 Jun;15(2):185-93.
PMID: 26777540 DOI: 10.1111/jocd.12209

Soap is the most useful things which we use our everyday life in various cleansing and cosmetics purposes. Jatropha oil is nonedible oil which has more benefits to soap making. It has also cosmetics and medicinal properties. But the presence of toxic Phorbol esters in Jatropha oil is the main constrains to use it. So it is necessary to search a more suitable method for detoxifying the Jatropha oil before the use as the main ingredient of soap production. This review implies a more suitable method for removing phorbol esters from Jatropha oil. Several parameters such as the % yield of pure Jatropha oil soap, TFM value of soap, total alkali content, free caustic alkalinity content, pH, the antimicrobial activity, and CMC value of general soap should be taken into consideration for soap from detoxified Jatropha oil.

Matched MeSH terms: Phorbol Esters/chemistry; Plant Oils/chemistry*; Soaps/chemistry*
Optimization of leachate treatment using persulfate/H2O2 based advanced oxidation process: case study: Deir El-Balah Landfill Site, Gaza Strip, Palestine

Hilles AH, Abu Amr SS, Hussein RA, Arafa AI, El-Sebaie OD

Water Sci Technol, 2016;73(1):102-12.
PMID: 26744940 DOI: 10.2166/wst.2015.468

The objective of this study was to investigate the performance of employing H2O2 reagent in persulfate activation to treat stabilized landfill leachate. A central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the relationships between operating variables, such as persulfate and H2O2 dosages, pH, and reaction time, to identify the optimum operating conditions. Quadratic models for the following two responses proved to be significant with very low probabilities (<0.0001): chemical oxygen demand (COD) and NH3-N removal. The obtained optimum conditions included a reaction time of 116 min, 4.97 g S2O8(2-), 7.29 g H2O2 dosage and pH 11. The experimental results were corresponding well with predicted models (COD and NH3-N removal rates of 81% and 83%, respectively). The results obtained in the stabilized leachate treatment were compared with those from other treatment processes, such as persulfate only and H2O2 only, to evaluate its effectiveness. The combined method (i.e., /S2O8(2-)/H2O2) achieved higher removal efficiencies for COD and NH3-N compared with other studied applications.

Matched MeSH terms: Hydrogen Peroxide/chemistry*; Sulfates/chemistry*; Sodium Compounds/chemistry*
Multivariate analysis of PRISMA optimized TLC image for predicting antioxidant activity and identification of contributing compounds from Pereskia bleo

Sharif KM, Rahman MM, Azmir J, Khatib A, Sabina E, Shamsudin SH, et al.

Biomed Chromatogr, 2015 Dec;29(12):1826-33.
PMID: 26033701 DOI: 10.1002/bmc.3503

Multivariate analysis of thin-layer chromatography (TLC) images was modeled to predict antioxidant activity of Pereskia bleo leaves and to identify the contributing compounds of the activity. TLC was developed in optimized mobile phase using the 'PRISMA' optimization method and the image was then converted to wavelet signals and imported for multivariate analysis. An orthogonal partial least square (OPLS) model was developed consisting of a wavelet-converted TLC image and 2,2-diphynyl-picrylhydrazyl free radical scavenging activity of 24 different preparations of P. bleo as the x- and y-variables, respectively. The quality of the constructed OPLS model (1 + 1 + 0) with one predictive and one orthogonal component was evaluated by internal and external validity tests. The validated model was then used to identify the contributing spot from the TLC plate that was then analyzed by GC-MS after trimethylsilyl derivatization. Glycerol and amine compounds were mainly found to contribute to the antioxidant activity of the sample. An alternative method to predict the antioxidant activity of a new sample of P. bleo leaves has been developed.

Matched MeSH terms: Plant Extracts/chemistry; Plant Leaves/chemistry; Cactaceae/chemistry*
Physicochemical factors and sources of particulate matter at residential urban environment in Kuala Lumpur

Khan F, Latif MT, Juneng L, Amil N, Mohd Nadzir MS, Syedul Hoque HM

J Air Waste Manag Assoc, 2015 Aug;65(8):958-69.
PMID: 26030827 DOI: 10.1080/10962247.2015.1042094

Long-term measurements (2004-2011) of PM10 (particulate matter with an aerodynamic diameter <10 μm) and trace gases (carbon monoxide [CO], ozone [O₃], nitrogen oxide [NO], oxides of nitrogen [NO(x)], nitrogen dioxide [NO₂], sulfur dioxide [SO₂], methane [CH₄], nonmethane hydrocarbon [NMHC]) have been conducted to study the effect of physicochemical factors on the PM10 concentration. In addition, this study includes source apportionment of PM10 in Kuala Lumpur urban environment. An advanced principal component analysis (PCA) technique coupled with absolute principal component scores (APCS) and multiple linear regression (MLR) has been applied. The average annual concentration of PM10 for 8 yr is 51.3 ± 25.8 μg m⁻³, which exceeds the Recommended Malaysian Air Quality Guideline (RMAQG) and international guideline values. Detail analysis shows the dependency of PM10 on the linear changes of the motor vehicles in use and the amount of biomass burning, particularly from Sumatra, Indonesia, during southwesterly monsoon. The main sources of PM10 identified by PCA-APCS-MLR are traffic combustion (28%), ozone coupled with meteorological factors (20%), and wind-blown particles (1%). However, the apportionment procedure left 28.0 μg m⁻³, that is, 51% of PM10 undetermined.

Matched MeSH terms: Air Pollutants/chemistry*; Gases/chemistry; Particulate Matter/chemistry*
Optimising the Azeotropic Drying of 18F-Fluorine Wayto Improve the 18F-Fluorocholine Radiochemical Yield

Hassan H, Bakar SA, Halim KN, Idris J, Saad FF, Nordin AJ

Curr Radiopharm, 2016;9(2):121-7.
PMID: 26239237

BACKGROUND AND OBJECTIVE: 18F-Fluorocholine has been suggested as one of the reputable imaging tracers for diagnosis of prostate tumour in Positron Emission Tomography / Computed Tomography (PET/CT) modality. Nevertheless, it has never been synthesised in Malaysia. We acknowledged that the major problem with 18F-Fluorocholine is due to its relatively low radiochemical yield at the end of synthesis (EOS). Therefore, this article presents improved 18FFluorocholine radiochemical yields after carrying out optimisation on azeotropic drying of 18F-Fluorine.
METHODS: In the previous study, the azeotropic drying of non-carrier-added (n.c.a) 18F-Fluorine in the reactor was conducted at atmospheric pressure (0 atm) and shorter duration time. In this study, however, the azeotropic drying of non-carried-added (n.c.a) 18FFluorine was made at a high vacuum pressure (- 0.65 to - 0.85 bar) with an additional time of 30 seconds. At the end of the synthesis, the mean radiochemical yield was statistically compared between the two azeotropic drying conditions so as to observe whether the improvement made was significant to the radiochemical yield.
RESULTS: From the paired sample t-test analysis, the improvement done to the azeotropic drying of non-carrier-added (n.c.a) 18F-Fluorine was statistically significant (p < 0.05). With the improvement made, the 18F-Fluorcholine radiochemical yield was found to have increase by one fold.
CONCLUSION: Improved 18F-Fluorocholine radiochemical yields were obtained after the improvement had been done to the azeotropic drying of non-carrier-added (n.c.a) 18F-Fluorine. It was also observed that improvement made to the azeotropic drying of non-carrier-added (n.c.a) 18F-Fluorine did not affect the 18F-Fluorocholine quality control analysis.

Matched MeSH terms: Fluorine Radioisotopes/chemistry*; Chemistry Techniques, Synthetic/methods
Arboridinine, a Pentacyclic Indole Alkaloid with a New Cage Carbon-Nitrogen Skeleton Derived from a Pericine Precursor

Wong SP, Gan CY, Lim KH, Ting KN, Low YY, Kam TS

Org. Lett., 2015 Jul 17;17(14):3628-31.
PMID: 26183592 DOI: 10.1021/acs.orglett.5b01757

A new monoterpene indole alkaloid characterized by an unprecedented pentacyclic cage skeleton, arboridinine (1), was isolated from a Malaysian Kopsia species. The structure and absolute configuration of the alkaloid were determined based on NMR, MS, and X-ray diffraction analysis. A possible biogenetic pathway from a pericine precursor is presented.

Matched MeSH terms: Alkaloids/chemistry*; Polycyclic Compounds/chemistry; Indole Alkaloids/chemistry
Effects of temperature change and beverage on mechanical and tribological properties of dental restorative composites

Ayatollahi MR, Yahya MY, Karimzadeh A, Nikkhooyifar M, Ayob A

Mater Sci Eng C Mater Biol Appl, 2015 Sep;54:69-75.
PMID: 26046269 DOI: 10.1016/j.msec.2015.05.004

The aim of this study was to investigate the effects of temperature change and immersion in two common beverages on the mechanical and tribological properties for three different types of dental restorative materials. Thermocycling procedure was performed for simulating temperature changes in oral conditions. Black tea and soft drink were considered for beverages. Universal composite, universal nanohybrid composite and universal nanofilled composite, were used as dental materials. The nanoindentation and nanoscratch experiments were utilized to determine the elastic modulus, hardness, plasticity index and wear resistance of the test specimens. The results showed that thermocycling and immersion in each beverage had different effects on the tested dental materials. The mechanical and tribological properties of nanohybrid composite and nanocomposite were less sensitive to temperature change and to immersion in beverages in comparison with those of the conventional dental composite.

Matched MeSH terms: Composite Resins/chemistry*; Dental Materials/chemistry*; Nanocomposites/chemistry*
Fulltext The Anticancer, Antioxidant and Antimicrobial Properties of the Sesquiterpene β-Caryophyllene from the Essential Oil of Aquilaria crassna

Dahham SS, Tabana YM, Iqbal MA, Ahamed MB, Ezzat MO, Majid AS, et al.

Molecules, 2015;20(7):11808-29.
PMID: 26132906 DOI: 10.3390/molecules200711808

The present study reports a bioassay-guided isolation of β-caryophyllene from the essential oil of Aquilaria crassna. The structure of β-caryophyllene was confirmed using FT-IR, NMR and MS. The antimicrobial effect of β-caryophyllene was examined using human pathogenic bacterial and fungal strains. Its anti-oxidant properties were evaluated by DPPH and FRAP scavenging assays. The cytotoxicity of β-caryophyllene was tested against seven human cancer cell lines. The corresponding selectivity index was determined by testing its cytotoxicity on normal cells. The effects of β-caryophyllene were studied on a series of in vitro antitumor-promoting assays using colon cancer cells. Results showed that β-caryophyllene demonstrated selective antibacterial activity against S. aureus (MIC 3 ± 1.0 µM) and more pronounced anti-fungal activity than kanamycin. β-Caryophyllene also displayed strong antioxidant effects. Additionally, β-caryophyllene exhibited selective anti-proliferative effects against colorectal cancer cells (IC50 19 µM). The results also showed that β-caryophyllene induces apoptosis via nuclear condensation and fragmentation pathways including disruption of mitochondrial membrane potential. Further, β-caryophyllene demonstrated potent inhibition against clonogenicity, migration, invasion and spheroid formation in colon cancer cells. These results prompt us to state that β-caryophyllene is the active principle responsible for the selective anticancer and antimicrobial activities of A. crassnia. β-Caryophyllene has great potential to be further developed as a promising chemotherapeutic agent against colorectal malignancies.

Matched MeSH terms: Oils, Volatile/chemistry*; Sesquiterpenes/chemistry; Thymelaeaceae/chemistry*
Fulltext Tongkat Ali (Eurycoma longifolia): a possible therapeutic candidate against Blastocystis sp

Girish S, Kumar S, Aminudin N

Parasit Vectors, 2015;8:332.
PMID: 26082155 DOI: 10.1186/s13071-015-0942-y

In the local Malaysian context, herbal plants such as Eurycoma longifolia (Tongkat Ali), Orthosiphon stamineus (MisaiKucing), Ficus deltoidea (Mas Cotek), Zingiber officinale (Halia Bara) and Barringtonia racemosa (Putat) are known and widely used for its therapeutic properties. The first part of this study aims to screen for the anti-protozoal activity of these herbal plant extracts against Blastocystis sp. isolate subtype (ST) 3. Herbal extract with the highest efficacy was further fractionized into water and ethyl acetate fractions and tested against ST1, ST3 and ST5 Blastocystis sp. isolates. These isolates were also exposed to allopathic drugs, Metronidazole (MTZ), Tinidazole, Trimethoprim-sulfamethoxazole(TMP-SMX), Ketoconazole and Nitazoxanide for comparison purpose.

Matched MeSH terms: Antiprotozoal Agents/chemistry; Plant Extracts/chemistry; Eurycoma/chemistry*
Characterization of natural low transition temperature mixtures (LTTMs): Green solvents for biomass delignification

Yiin CL, Quitain AT, Yusup S, Sasaki M, Uemura Y, Kida T

Bioresour Technol, 2016 Jan;199:258-264.
PMID: 26253419 DOI: 10.1016/j.biortech.2015.07.103

The aim of this work was to characterize the natural low transition temperature mixtures (LTTMs) as promising green solvents for biomass pretreatment with the critical characteristics of cheap, biodegradable and renewable, which overcome the limitations of ionic liquids (ILs). The LTTMs were derived from inexpensive commercially available hydrogen bond acceptor (HBA) and l-malic acid as the hydrogen bond donor (HBD) in distinct molar ratios of starting materials and water. The peaks involved in the H-bonding shifted and became broader for the OH groups. The thermal properties of the LTTMs were not affected by water while the biopolymers solubility capacity of LTTMs was improved with the increased molar ratio of water and treatment temperature. The pretreatment of oil palm biomass was consistence with the screening on solubility of biopolymers. This work provides a cost-effective alternative to utilize microwave hydrothermal extracted green solvents such as malic acid from natural fruits and plants.

Matched MeSH terms: Biopolymers/chemistry; Solvents/chemistry*; Water/chemistry
Development and evaluation of electromembrane extraction across a hollow polymer inclusion membrane

Mamat NA, See HH

J Chromatogr A, 2015 Aug 7;1406:34-9.
PMID: 26141273 DOI: 10.1016/j.chroma.2015.06.020

In this work, a new variation of the electromembrane extraction (EME) approach employing a hollow polymer inclusion membrane (HPIM) was developed. In this method, a HPIM was prepared by casting a solution of the desired proportions of cellulose acetate (CTA), tris(2-ethylhexyl)phosphate (TEHP) and di-(2-ethylhexyl)phosphoric acid (D2EHPA) in dichloromethane on glass capillary tubing. Three basic drugs namely amphetamine, methamphetamine, and 3,4-methylenedioxy-N-methylamphetamine (MDMA) were selected as model analytes to evaluate the extraction performance of this new approach. The drugs were extracted from human plasma samples, through a 20μm thickness HPIM, to an aqueous acceptor solution inside the lumen of the hollow membrane. Parameters affecting the extraction efficiency were investigated in detail. Under the optimized conditions, enrichment factors in the range of 97-103-fold were obtained from 3mL of sample solution with a 10min extraction time and an applied voltage of 300V across the HPIM. The detection limits of the method for the three drugs were in the range of 1.0-2.5ng/mL (at a signal/noise ratio of three), with relative standard deviations of between 6.4% and 7.9%. When the method was applied to spiked plasma samples, the relative recoveries ranged from 99.2% to 100.8%. Enrichment factors of 103, 99 and 97 were obtained for amphetamine, methamphetamine, and MDMA, respectively. A comparison was also made between the newly developed approach and EME using supported liquid membranes (SLM) as well as standard sample preparation methods (liquid-liquid extraction) used by the Toxicology Unit, Department of Chemistry, Malaysia.

Matched MeSH terms: Cellulose/chemistry; Organophosphates/chemistry; Polymers/chemistry
Fulltext A Novel Aqueous Two Phase System Composed of Surfactant and Xylitol for the Purification of Lipase from Pumpkin (Cucurbita moschata) Seeds and Recycling of Phase Components

Amid M, Manap MY, Hussin M, Mustafa S

Molecules, 2015 Jun 17;20(6):11184-201.
PMID: 26091076 DOI: 10.3390/molecules200611184

Lipase is one of the more important enzymes used in various industries such as the food, detergent, pharmaceutical, textile, and pulp and paper sectors. A novel aqueous two-phase system composed of surfactant and xylitol was employed for the first time to purify lipase from Cucurbita moschata. The influence of different parameters such as type and concentration of surfactants, and the composition of the surfactant/xylitol mixtures on the partitioning behavior and recovery of lipase was investigated. Moreover, the effect of system pH and crude load on the degree of purification and yield of the purified lipase were studied. The results indicated that the lipase was partitioned into the top surfactant rich phase while the impurities partitioned into the bottom xylitol-rich phase using an aqueous two phase system composed of 24% (w/w) Triton X-100 and 20% (w/w) xylitol, at 56.2% of tie line length (TLL), (TTL is one of the important parameters in this study and it is determined from a bimodal curve in which the tie-line connects two nodes on the bimodal, that represent concentration of phase components in the top and bottom phases) and a crude load of 25% (w/w) at pH 8.0. Recovery and recycling of components was also measured in each successive step process. The enzyme was successfully recovered by the proposed method with a high purification factor of 16.4 and yield of 97.4% while over 97% of the phase components were also recovered and recycled. This study demonstrated that the proposed novel aqueous two phase system method is more efficient and economical than the traditional aqueous two phase system method for the purification and recovery of the valuable enzyme lipase.

Matched MeSH terms: Lipase/chemistry*; Seeds/chemistry*; Cucurbita/chemistry*
Silver Nanoparticle Coated Bioactive Glasses--Composites with Dex/CMC Hydrogels: Characterization, Solubility, and In Vitro Biological Studies

Wren AW, Hassanzadeh P, Placek LM, Keenan TJ, Coughlan A, Boutelle LR, et al.

Macromol Biosci, 2015 Aug;15(8):1146-58.
PMID: 25923463 DOI: 10.1002/mabi.201500109

Silver (Ag) coated bioactive glass particles (Ag-BG) were formulated and compared to uncoated controls (BG) in relation to glass characterization, solubility and microbiology. X-ray diffraction (XRD) confirmed a crystalline AgNP surface coating while ion release studies determined low Ag release (<2 mg/L). Cell culture studies presented increased cell viability (127 and 102%) with lower liquid extract (50 and 100 ml/ml) concentrations. Antibacterial testing of Ag-BG in E. coli, S. epidermidis and S. aureus significantly reduced bacterial cell viability by 60-90%. Composites of Ag-BG/CMC-Dex Hydrogels were formulated and characterized. Agar diffusion testing was conducted where Ag-BG/hydrogel composites produced the largest inhibition zones of 7 mm (E. coli), 5 mm (S. aureus) and 4 mm (S. epidermidis).

Matched MeSH terms: Silver/chemistry*; Hydrogels/chemistry*; Metal Nanoparticles/chemistry*
Formation and reduction of 5-hydroxymethylfurfural at frying temperature in model system as a function of amino acid and sugar composition

Kavousi P, Mirhosseini H, Ghazali H, Ariffin AA

Food Chem, 2015 Sep 1;182:164-70.
PMID: 25842323 DOI: 10.1016/j.foodchem.2015.02.135

5-Hydroxymethylfurfural (HMF) is formed during heat treatment of carbohydrate-containing foods, especially in a deep-fat frying process. This study aimed to investigate the effect of amino acids on the formation and reduction of HMF from glucose, fructose and sucrose at frying temperature in model systems containing binary mixtures of an amino acid and a sugar in equal concentrations (0.3M). The results revealed that the formation of HMF from sugars accelerated in the presence of acidic amino acids (i.e. glutamic and aspartic acids). Conversely, the presence of basic amino acids (i.e. lysine, arginine and histidine) led to reduced concentrations of HMF to non-detectable levels in model systems. The results showed that both pH and heating time significantly affected the formation of HMF from fructose in the presence of glutamic acid. In this regard, a higher amount of HMF was formed at lower pH.

Matched MeSH terms: Amino Acids/chemistry; Carbohydrates/chemistry; Furaldehyde/chemistry

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