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Fulltext Seeded Growth Route to Noble Calcium Carbonate Nanocrystal

Islam A, Teo SH, Rahman MA, Taufiq-Yap YH

PLoS One, 2015;10(12):e0144805.
PMID: 26700479 DOI: 10.1371/journal.pone.0144805

A solution-phase route has been considered as the most promising route to synthesize noble nanostructures. A majority of their synthesis approaches of calcium carbonate (CaCO3) are based on either using fungi or the CO2 bubbling methods. Here, we approached the preparation of nano-precipitated calcium carbonate single crystal from salmacis sphaeroides in the presence of zwitterionic or cationic biosurfactants without external source of CO2. The calcium carbonate crystals were rhombohedron structure and regularly shaped with side dimension ranging from 33-41 nm. The high degree of morphological control of CaCO3 nanocrystals suggested that surfactants are capable of strongly interacting with the CaCO3 surface and control the nucleation and growth direction of calcium carbonate nanocrystals. Finally, the mechanism of formation of nanocrystals in light of proposed routes was also discussed.

Matched MeSH terms: Microscopy, Electron, Scanning
Fulltext Neutron-activated biodegradable samarium-153 acetylacetonate-poly-L-lactic acid microspheres for intraarterial radioembolization of hepatic tumors

Wong YH, Tan HY, Kasbollah A, Abdullah BJJ, Acharya RU, Yeong CH

World J Exp Med, 2020 Mar 30;10(2):10-25.
PMID: 32266125 DOI: 10.5493/wjem.v10.i2.10

BACKGROUND: Liver cancer is the 6th most common cancer in the world and the 4th most common death from cancer worldwide. Hepatic radioembolization is a minimally invasive treatment involving intraarterial administration of radioembolic microspheres.
AIM: To develop a neutron-activated, biodegradable and theranostics samarium-153 acetylacetonate (153SmAcAc)-poly-L-lactic acid (PLLA) microsphere for intraarterial radioembolization of hepatic tumors.
METHODS: Microspheres with different concentrations of 152SmAcAc (i.e., 100%, 150%, 175% and 200% w/w) were prepared by solvent evaporation method. The microspheres were then activated using a nuclear reactor in a neutron flux of 2 × 1012 n/cm2/s1, converting 152Sm to Samarium-153 (153Sm) via152Sm (n, γ) 153Sm reaction. The SmAcAc-PLLA microspheres before and after neutron activation were characterized using scanning electron microscope, energy dispersive X-ray spectroscopy, particle size analysis, Fourier transform infrared spectroscopy, thermo-gravimetric analysis and gamma spectroscopy. The in-vitro radiolabeling efficiency was also tested in both 0.9% sodium chloride solution and human blood plasma over a duration of 550 h.
RESULTS: The SmAcAc-PLLA microspheres with different SmAcAc contents remained spherical before and after neutron activation. The mean diameter of the microspheres was about 35 µm. Specific activity achieved for 153SmAcAc-PLLA microspheres with 100%, 150%, 175% and 200% (w/w) SmAcAc after 3 h neutron activation were 1.7 ± 0.05, 2.5 ± 0.05, 2.7 ± 0.07, and 2.8 ± 0.09 GBq/g, respectively. The activity of per microspheres were determined as 48.36 ± 1.33, 74.10 ± 1.65, 97.87 ± 2.48, and 109.83 ± 3.71 Bq for 153SmAcAc-PLLA microspheres with 100%, 150%, 175% and 200% (w/w) SmAcAc. The energy dispersive X-ray and gamma spectrometry showed that no elemental and radioactive impurities present in the microspheres after neutron activation. Retention efficiency of 153Sm in the SmAcAc-PLLA microspheres was excellent (approximately 99%) in both 0.9% sodium chloride solution and human blood plasma over a duration of 550 h.
CONCLUSION: The 153SmAcAc-PLLA microsphere is potentially useful for hepatic radioembolization due to their biodegradability, favorable physicochemical characteristics and excellent radiolabeling efficiency. The synthesis of the formulation does not involve ionizing radiation and hence reducing the complication and cost of production.

Matched MeSH terms: Microscopy, Electron, Scanning
Fulltext Formulation development and dissolution rate enhancement of efavirenz by solid dispersion systems

Koh PT, Chuah JN, Talekar M, Gorajana A, Garg S

Indian J Pharm Sci, 2013 May;75(3):291-301.
PMID: 24082345 DOI: 10.4103/0250-474X.117434

The aim of this study was to enhance the dissolution rate of efavirenz using solid dispersion systems (binary and ternary). A comparison between solvent and fusion method was also investigated. Solid dispersions of efavirenz were prepared using polyethylene glycol 8000, polyvinylpyrrolidone K30 alone and combination of both. Tween 80 was incorporated to obtain a ternary solid dispersion system. Dissolution tests were conducted and evaluated on the basis of cumulative percentage drug release and dissolution efficiency. Physicochemical characterizations of the solid dispersions were carried out using differential scanning calorimetric, powder X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Dissolution was remarkably improved in both systems compared to pure efavirenz (P<0.05). An optimum ratio was identified at a drug:polymer of 1:10. Incorporation of Tween 80 to 1:10 formulations formed using solvent method showed further improvement in the dissolution rate. Physicochemical characterization results suggested that efavirenz existed in the amorphous form in all the solid dispersion systems providing evidence of improvement in dissolution. No statistically significant difference (P>0.05) in dissolution was observed between the two methods. Binary and ternary solid dispersion systems both have showed a significant improvement in the dissolution rate of efavirenz. Formulations with only polyvinylpyrrolidone K30 showed best dissolution profile and 1:10 was identified as an optimum drug-polymer weight ratio.

Matched MeSH terms: Microscopy, Electron, Scanning
Fulltext Development and characterization of polymeric microspheres for controlled release protein loaded drug delivery system

Ravi S, Peh KK, Darwis Y, Murthy BK, Singh TR, Mallikarjun C

Indian J Pharm Sci, 2008 May-Jun;70(3):303-9.
PMID: 20046737 DOI: 10.4103/0250-474X.42978

The aim of the present work was to investigate the preparation of microspheres as potential drug carriers for proteins, intended for controlled release formulation. The hydrophilic bovine serum albumin was chosen as a model protein to be encapsulated within poly(D,L-lactide-co-glycolide) (50:50) microspheres using a w/o/w double emulsion solvent evaporation method. Different parameters influencing the particle size, entrapment efficiency and in vitro release profiles were investigated. The microspheres prepared with different molecular weight and hydrophilicity of poly(D,L-lactide-co-glycolide) polymers were non porous, smooth surfaced and spherical in structure under scanning electron microscope with a mean particle size ranging from 3.98 to 8.74 mum. The protein loading efficiency varied from 40 to 71% of the theoretical amount incorporated. The in vitro release profile of bovine serum albumin from microspheres presented two phases, initial burst release phase due to the protein adsorbed on the microsphere surface, followed by slower and continuous release phase corresponding to the protein entrapped in polymer matrix. The release rate was fairly constant after an initial burst release. Consequently, these microspheres can be proposed as new controlled release protein delivery system.

Matched MeSH terms: Microscopy, Electron, Scanning
Fulltext Characterization of electrosynthesized conjugated polymer-carbon nanotube composite: optical nonlinearity and electrical property

Bahrami A, Talib ZA, Shahriari E, Yunus WMM, Kasim A, Behzad K

Int J Mol Sci, 2012;13(1):918-928.
PMID: 22312294 DOI: 10.3390/ijms13010918

The effects of multi-walled carbon nanotube (MWNT) concentration on the structural, optical and electrical properties of conjugated polymer-carbon nanotube composite are discussed. Multi-walled carbon nanotube-polypyrrole nanocomposites were synthesized by electrochemical polymerization of monomers in the presence of different amounts of MWNTs using sodium dodecylbenzensulfonate (SDBS) as surfactant at room temperature and normal pressure. Field emission scanning electron microscopy (FESEM) indicates that the polymer is wrapped around the nanotubes. Measurement of the nonlinear refractive indices (n(2)) and the nonlinear absorption (β) of the samples with different MWNT concentrations measurements were performed by a single Z-scan method using continuous wave (CW) laser beam excitation wavelength of λ = 532 nm. The results show that both nonlinear optical parameters increased with increasing the concentration of MWNTs. The third order nonlinear susceptibilities were also calculated and found to follow the same trend as n(2) and β. In addition, the conductivity of the composite film was found to increase rapidly with the increase in the MWNT concentration.

Matched MeSH terms: Microscopy, Electron, Scanning
Fulltext Controlling the degradation kinetics of porous iron by poly(lactic-co-glycolic acid) infiltration for use as temporary medical implants

Yusop AH, Daud NM, Nur H, Kadir MR, Hermawan H

Sci Rep, 2015;5:11194.
PMID: 26057073 DOI: 10.1038/srep11194

Iron and its alloy have been proposed as biodegradable metals for temporary medical implants. However, the formation of iron oxide and iron phosphate on their surface slows down their degradation kinetics in both in vitro and in vivo scenarios. This work presents new approach to tailor degradation behavior of iron by incorporating biodegradable polymers into the metal. Porous pure iron (PPI) was vacuum infiltrated by poly(lactic-co-glycolic acid) (PLGA) to form fully dense PLGA-infiltrated porous iron (PIPI) and dip coated into the PLGA to form partially dense PLGA-coated porous iron (PCPI). Results showed that compressive strength and toughness of the PIPI and PCPI were higher compared to PPI. A strong interfacial interaction was developed between the PLGA layer and the iron surface. Degradation rate of PIPI and PCPI was higher than that of PPI due to the effect of PLGA hydrolysis. The fast degradation of PIPI did not affect the viability of human fibroblast cells. Finally, this work discusses a degradation mechanism for PIPI and the effect of PLGA incorporation in accelerating the degradation of iron.

Matched MeSH terms: Microscopy, Electron, Scanning
Fulltext Expanding Opportunities for Science, Technology, Engineering and Mathematics Subjects Teaching and Learning: Connecting through Comics

Adnan M, Abdullah JM, Ibharim LFM, Hoe TW, Janan D, Abdullah N, et al.

Malays J Med Sci, 2019 Jul;26(4):127-133.
PMID: 31496902 MyJurnal DOI: 10.21315/mjms2019.26.4.15

This study presents the results of a year-long project focused on analysis and reflection on working with comics by Year One students in Hulu Langat districts. This study presents the use of science, technology, engineering and mathematics (STEM) comics to help children understand certain physical phenomena and try to make students interested in mathematics and science subject. Thirteen excellent teachers of science and mathematics from the Hulu Langat district were involved in the analysis of syllabus Year One science and mathematics subjects and the preparation of scripts while the STEM comic illustrator was created by two lecturers from the Faculty of Art, Computing and Creative Industry from Universiti Pendidikan Sultan Idris, Perak Malaysia. The study is based on observations of changing perception of phenomena by children as a result of the use of comics. As a result, a STEM comic that contains ten series for Year One science and mathematics subjects has been successfully developed. This comic is expected to attract and enhance the achievement of Year One students in science and mathematics. Implication of this study, STEM comics can be used by teachers as science and mathematics teaching aids. Comics are proven to be a modern pedagogical strategy, which is starting to gain its popularity in teaching about mathematics and science. Comics can be very helpful tools in making science and mathematics concepts interesting, fun learning and comprehensible for a Year One children.

Matched MeSH terms: Microscopy, Electron, Scanning Transmission
Fulltext Antiproliferative Properties of Clausine-B against Cancer Cell Lines

Wan Mohd Zain WN, Rahmat A, Othman F, Yap TY

Malays J Med Sci, 2009 Jul;16(3):29-34.
PMID: 22589662 MyJurnal

CLAUSINE B, A CARBAZOLE ALKALOID ISOLATED FROM THE STEM BARK OF CLAUSENA EXCAVATA, WAS INVESTIGATED FOR ITS ANTIPROLIFERATIVE ACTIVITIES AGAINST FIVE HUMAN CANCER CELL LINES: HepG2 (hepatic cancer), MCF-7 (hormone-dependent breast cancer), MDA-MB-231 (non-hormone-dependent breast cancer), HeLa (cervical cancer), and CAOV3 (ovarian cancer).

Matched MeSH terms: Microscopy, Electron, Scanning Transmission
Fulltext Highly porous regenerated cellulose hydrogel and aerogel prepared from hydrothermal synthesized cellulose carbamate

Gan S, Zakaria S, Chia CH, Chen RS, Ellis AV, Kaco H

PLoS One, 2017;12(3):e0173743.
PMID: 28296977 DOI: 10.1371/journal.pone.0173743

Here, a stable derivative of cellulose, called cellulose carbamate (CC), was produced from Kenaf (Hibiscus cannabinus) core pulp (KCP) and urea with the aid of a hydrothermal method. Further investigation was carried out for the amount of nitrogen yielded in CC as different urea concentrations were applied to react with cellulose. The effect of nitrogen concentration of CC on its solubility in a urea-alkaline system was also studied. Regenerated cellulose products (hydrogels and aerogels) were fabricated through the rapid dissolution of CC in a urea-alkaline system. The morphology of the regenerated cellulose products was viewed under Field emission scanning electron microscope (FESEM). The transformation of allomorphs in regenerated cellulose products was examined by X-ray diffraction (XRD). The transparency of regenerated cellulose products was determined by Ultraviolet-visible (UV-Vis) spectrophotometer. The degree of swelling (DS) of regenerated cellulose products was also evaluated. This investigation provides a simple and efficient procedure of CC determination which is useful in producing regenerated CC products.

Matched MeSH terms: Microscopy, Electron, Scanning
A novel photocatalytic degradation of mixed dye through chemically synthesized ZnO/Fe2O3 nanocomposite

Manojkumar U, Kaliannan D, Balasubramanian B, Kamyab H, Vasseghian Y, Chelliapan S, et al.

Environ Geochem Health, 2024 Jun 07;46(7):221.
PMID: 38849635 DOI: 10.1007/s10653-024-02000-8

This study reported the synthesis and assessment of zinc oxide/iron oxide (ZnO/Fe2O3) nanocomposite as photocatalysts for the degradation of a mixture of methylene red and methylene blue dyes. X-ray diffraction analysis confirms that the crystallite of zinc oxide (ZnO) has a hexagonal wurtzite phase and iron oxide (Fe2O3) has a rhombohedral phase. Fourier Transform Infra-Red spectrum confirms the presence of Zn-O vibration stretching at 428, 480 and 543 cm-1 stretching confirming Fe-O bond formation. Scanning Electron Microscope images exhibited a diverse size and shape of the nanocomposites. The ZnO-90%/Fe2O3-10% and ZnO-10%/Fe2O3-90% nanocomposites reveal good photocatalytic activity with reaction rate constants of 1.5 × 10-2 and 0.66 × 10-2; and 1.3 × 10-2 and 0.60 × 10-2 for methylene blue and methyl red dye respectively. The results revealed that the synthesized ZnO/Fe2O3 nanocomposite is the best catalyst for dye degradation and can be used for industrial applications in future.

Matched MeSH terms: Microscopy, Electron, Scanning
Fulltext Study the effect of various wash-coated metal oxides over synthesized carbon nanofibers coated monolith substrates

Malekbala MR, Soltani S, Abdul Rashid S, Abdullah LC, Choong TSY

PLoS One, 2019;14(7):e0219936.
PMID: 31365558 DOI: 10.1371/journal.pone.0219936

In this research work, carbon nanofibers (CNFs) were synthesized on honeycomb monolith substrates using injection chemical vapor deposition (ICVD) technique. The effect of various wash-coated materials and catalyst promoter on the growth rate of CNFs on monolith substrates were examined. The characteristics of the synthesized CNFs-coated monolith composites were examined using Raman spectroscopy, Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FE-SEM), and Transmission electron microscopy (TEM) techniques. According to the textural characterization study, the specific surface area and pore volume of CNFs-coated monolith composites were significantly improved as compared to bare monolith which might be attributed to the growth of highly pure and aligned CNFs over monolith substrate. Besides that, the synthesized CNFs-coated monolith possessed extremely well thermal stability up to the temperature of 550 °C which was corresponded to the strong attachment of highly graphitized CNFs over monolith substrates.

Matched MeSH terms: Microscopy, Electron, Transmission
Alginate-based bipolymeric-nanobioceramic composite matrices for sustained drug release

Hasnain MS, Nayak AK, Singh M, Tabish M, Ansari MT, Ara TJ

Int J Biol Macromol, 2016 Feb;83:71-7.
PMID: 26608007 DOI: 10.1016/j.ijbiomac.2015.11.044

Alginate-based bipolymeric-nanobioceramic composite matrices for sustained drug release were developed through incorporation of nano-hydroxyapatite [nHAp] powders within ionotropically-gelled calcium ion-induced alginate-poly (vinyl pyrrolidone) blends polymeric systems. nHAp powders were synthesized by precipitation technique using calcium hydroxide [Ca(OH)2] and orthophosphoric acid [H3PO4] as raw materials. The average particle size of these was synthesized. nHAp powders was found as 19.04 nm and used to prepare nHAp-alginate-PVP beads containing DS. These beads exhibited drug entrapment efficiency (%) of 65.82±1.88 to 94.45±3.72% and average bead sizes of 0.98±0.07 to 1.23±0.15 mm. These beads were characterized by scanning electron microscopy (SEM) and Fourier transform-infra red (FTIR) spectroscopy analyses. Various nHAp-alginate-PVP beads containing DS exhibited prolonged sustained drug release and followed the Koresmeyer-Peppas model of drug release (R2=0.9908-0.9978) with non-Fickian release (anomalous transport) mechanism (n=0.73-0.84) for drug release over 8 h.

Matched MeSH terms: Microscopy, Electron, Scanning/methods
Fulltext Embryos of the viviparous dermapteran, Arixenia esau develop sequentially in two compartments: terminal ovarian follicles and the uterus

Tworzydlo W, Kisiel E, Bilinski SM

PLoS One, 2013;8(5):e64087.
PMID: 23667700 DOI: 10.1371/journal.pone.0064087

Three main reproductive strategies have been described among insects: most common oviparity, ovoviviparity and viviparity. In the latter strategy, the embryonic development takes place within the body of the mother which provides gas exchange and nutrients for embryos. Here we present the results of histological and EM analyses of the female reproductive system of the viviparous earwig, Arixenia esau, focusing on all the modifications related to the viviparity. We show that in the studied species the embryonic development consists of two "physiological phases" that take place in two clearly disparate compartments, i.e. the terminal ovarian follicle and the uterus. In both compartments the embryos are associated with synthetically active epithelial cells. We suggest that these cells are involved in the nourishment of the embryo. Our results indicate that viviparity in arixeniids is more complex than previously considered. We propose the new term "pseudoplacento-uterotrophic viviparity" for this unique two-phase reproductive strategy.

Matched MeSH terms: Microscopy, Electron, Scanning; Microscopy, Electron, Transmission
Preparation, characterisation and viability of encapsulated Trichoderma harzianum UPM40 in alginate-montmorillonite clay

Adzmi F, Meon S, Musa MH, Yusuf NA

J Microencapsul, 2012;29(3):205-10.
PMID: 22309479 DOI: 10.3109/02652048.2012.659286

Microencapsulation is a process by which tiny parcels of an active ingredient are packaged within a second material for the purpose of shielding the active ingredient from the surrounding environment. This study aims to determine the ability of the microencapsulation technique to improve the viability of Trichoderma harzianum UPM40 originally isolated from healthy groundnut roots as effective biological control agents (BCAs). Alginate was used as the carrier for controlled release, and montmorillonite clay (MMT) served as the filler. The encapsulated Ca-alginate-MMT beads were characterised using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The FTIR results showed the interaction between the functional groups of alginate and MMT in the Ca-alginate-MMT beads. Peaks at 1595, 1420 and 1020 cm(-1) characterised alginate, and peaks at 1028 and 453 cm(-1) characterised MMT; both sets of peaks appeared in the Ca-alginate-MMT FTIR spectrum. The TGA analysis showed an improvement in the thermal stability of the Ca-alginate-MMT beads compared with the alginate beads alone. SEM analysis revealed a homogeneous distribution of the MMT particles throughout the alginate matrix. T. harzianum UPM40 was successfully encapsulated in the Ca-alginate-MMT beads. Storage analysis of the encapsulated T. harzianum UPM40 showed that the low storage temperature of 5°C resulted in significantly (p

Matched MeSH terms: Microscopy, Electron, Scanning/methods
Fulltext Real time anti-Toxoplasma gondii activity of an active fraction of Eurycoma longifolia root studied by in situ scanning and transmission electron microscopy

Kavitha N, Noordin R, Kit-Lam C, Sasidharan S

Molecules, 2012 Aug 02;17(8):9207-19.
PMID: 22858841 DOI: 10.3390/molecules17089207

The inhibitory effect of active fractions of Eurycoma longifolia (E. longifolia) root, namely TAF355 and TAF401, were evaluated against Toxoplasma gondii (T. gondii). In our previous study, we demonstrated that T. gondii was susceptible to TAF355 and TAF401 with IC₅₀ values of 1.125 µg/mL and 1.375 µg/mL, respectively. Transmission (TEM) and scanning electron microscopy (SEM) observations were used to study the in situ antiparasitic activity at the IC₅₀ value. Clindamycin was used as positive control. SEM examination revealed cell wall alterations with formation of invaginations followed by completely collapsed cells compared to the normal T. gondii cells in response to the fractions. The main abnormality noted via TEM study was decreased cytoplasmic volume, leaving a state of structural disorganization within the cell cytoplasm and destruction of its organelles as early as 12 h of treatment, which indicated of rapid antiparasitic activity of the E. longifolia fractions. The significant antiparasitic activity shown by the TAF355 and TAF401 active fractions of E. longifolia suggests their potential as new anti-T. gondii agent candidates.

Matched MeSH terms: Microscopy, Electron, Scanning; Microscopy, Electron, Transmission
Phenotypic 'variant' forms of Trichomonas vaginalis trophozoites from cervical neoplasia patients

Yusof AM, Kumar S

Exp Parasitol, 2012 Jul;131(3):267-73.
PMID: 22525014 DOI: 10.1016/j.exppara.2012.03.015

The protozoan Trichomonas vaginalis a sexually transmitted protozoan parasite causes vaginitis, urethritis and cervicitis in humans. The present study highlights phenotypic 'variant' forms of trophozoites isolated from patients suffering from cervical neoplasia condition. The growth curve of 10 isolates i.e., four non-cervical neoplasia (NCN) isolates (NCN1-NCN4) and six cervical neoplasia (CN) isolates (CN1-CN6) showed two distinct and different in vitro growth profiles. The parasite count and growth rates were significantly higher in trophozoites from CN isolates in cultures of day 2 up to day 8 (p<0.05, Mann-Whitney test). The average generation time was 1.84±0.40 and 3.38±0.55h for NCN and CN isolates respectively. The nucleus of trophozoites in CN isolates using acridine orange and DAPI showed more intense staining revealing higher nuclear content. The FITC-labeled Concanavalin A stained stronger green fluorescence with surface of trophozoites in CN isolates showing more rough and creased surface with numerous deep micropores. Transmission electron microscopy studies revealed that there was higher numbers of vacuoles and hydrogenosomes in these forms. The study mounted staining techniques, growth profiles, morphology, morphometry studies using scanning and transmission electron microscopy and confirms that the trophozoites from cervical neoplasia proliferates at a higher rate, shows higher FITC-labeled Concanavalin A binding with rough and creased surface implying that these are virulent forms which can aggravate or exacerbate cervical neoplasia conditions. The large numbers of hyrogenosomes and vacuoles implies that these forms are active and implicates a possible role in such conditions.

Matched MeSH terms: Microscopy, Electron, Scanning; Microscopy, Electron, Transmission
In vitro and in situ antiyeast activity of Gracilaria changii methanol extract against Candida albicans

Sasidharan S, Darah I, Jain K

Eur Rev Med Pharmacol Sci, 2011 Sep;15(9):1020-6.
PMID: 22013724

The Gracilaria (G.) sp are widely used in the traditional medicine in Malaysia. The methanol extract of Gracilaria changii B.M. Xia & I.A. Abbott (Gracilariaciae) was evaluated for antiyeast activity against Candida albicans (Berkhout).

Matched MeSH terms: Microscopy, Electron, Scanning; Microscopy, Electron, Transmission
Removal of nickel ion from aqueous solution using Rambai stem (Baccaurea motleyana) adsorbent

Khuzaimah N, Nour UM, Maitra S

J Environ Sci Eng, 2011 Jul;53(3):257-62.
PMID: 23029925

The presence of heavy metals in the environment results in a number of environmental problems. In this study, the potential of Rambai stem (Baccaurea motleyana) of Malaysia in removing nickel ion from aqueous solution has been evaluated. The raw material used in this study was obtained from local orchard. The collected material passed through physical preparation and treatment process. The adsorbent was thoroughly characterized by SEM, EDX and FTIR studies. The effect of initial nickel concentration, dosage of adsorbent and pH on the adsorption process were investigated. The highest adsorption capacity obtained at weak acidic conditions (pH 4-5) when dosage and initial concentrations are 0.1 and 30 ppm respectively. The percentage of removal of nickel from the solution was found to be 51%. The experimental data fitted well in Freundlich isotherms indicating the adsorption of nickel on Rambai stem (Baccaurea motleyana) followed heterogenous surface phenomena.

Matched MeSH terms: Microscopy, Electron, Scanning/methods
Antibacterial activity and morphological changes of Pseudomonas aeruginosa cells after exposure to Vernonia cinerea extract

Latha LY, Darah I, Kassim MJ, Sasidharan S

Ultrastruct Pathol, 2010 Aug;34(4):219-25.
PMID: 20594042 DOI: 10.3109/01913121003651513

The antibacterial activity of Vernonia cinerea (L.) extract was investigated using the broth dilution method. The extract showed a favorable antimicrobial activity against Pseudomonas aeruginosa with a minimum inhibition concentration (MIC) value of 3.13 mg/mL. V. cinerea extract at (1/2), 1, or 2 times the MIC significantly inhibited bacterial growth with a noticeable drop in optical density (OD) of the bacterial culture, thus confirming the antibacterial activity of the extract on P. aeruginosa. Imaging using scanning (SEM) and transmission (TEM) electron microscopy was done to determine the major alterations in the microstructure of the extract-treated P. aeruginosa. The main abnormalities noted via SEM and TEM studies were the alteration in morphology of the bacterial cells. The main reason for this destruction was the severe alterations of the cell wall with the formation of holes, invaginations, and morphological disorganization caused by the extract. The authors conclude that the extract may be used as a candidate for the development of antimicrobial agents.

Matched MeSH terms: Microscopy, Electron, Scanning; Microscopy, Electron, Transmission
Fulltext Toxic effects of Litsea elliptica Blume essential oil on red blood cells of Sprague-Dawley rats

Taib IS, Budin SB, Siti Nor Ain SM, Mohamed J, Louis SR, Das S, et al.

J Zhejiang Univ Sci B, 2009 Nov;10(11):813-9.
PMID: 19882755 DOI: 10.1631/jzus.B0920199

Litsea elliptica Blume leaves have been traditionally used as medicinal herbs because of its antimutagenicity, chemopreventative and insecticidal properties. In this study, the toxic effects of L. elliptica essential oil against Sprague-Dawley rat's red blood cells (RBCs) were evaluated. L. elliptica essential oil was given by oral gavage 5 times per week for 3 treated groups in the doses of 125, 250, and 500 mg/(kg body weight), respectively, and the control group received distilled water. Full blood count, RBC osmotic fragility, RBC morphological changes, and RBC membrane lipid were analyzed 28 d after the treatment. Although L. elliptica essential oil administration had significantly different effects on hemoglobin (Hb), mean cell hemoglobin concentration (MCHC), mean cell volume (MCV), and mean cell hemoglobin (MCH) in the experimental groups as compared to the control group (P<0.05), the values were still within the normal range. L. elliptica induced morphological changes of RBC into the form of echinocyte. The percentage of echinocyte increased significantly among the treated groups in a dose-response manner (P<0.001). The concentrations of RBC membrane phospholipids and cholesterol of all treated groups were significantly lower than those of control group (P<0.001). However, the RBC membrane osmotic fragility and total proteins of RBC membrane findings did not differ significantly between control and treated groups (P>0.05). It is concluded that structural changes in the RBC membrane due to L. elliptica essential oil administration did not cause severe membrane damage.

Matched MeSH terms: Microscopy, Electron, Scanning/methods

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