Displaying publications 2741 - 2760 of 2920 in total

Abstract:
Sort:
  1. Bera Lake water quality, past and present situation
    Gharibrezal M, Ashraf MA
    J Environ Biol, 2016 09;37(5 Spec No):1097-1104.
    PMID: 29989741
    Bera Lake is the largest natural fresh water reservoir in Malaysia. It has vital environmental and ecological importance for human and wild life. Nevertheless, water quality of this lake has been degraded during the last few decades due to land development projects at catchment area. Therefore, a comprehensive water quality assessment of Bera Lake was implemented in order to compare current water quality with the implementation of land development projects. In situ water quality surveying was implemented using calibrated full option Hydrolab DS 5. Eleven parameters viz., temperature, depth of sampling, salinity, Turbidity, total dried solid, pH, NH4(+), N03(-), Cl(-), saturation percentage of dissolved oxygen, specific conductivity were recorded in fifty one stations at 0.2h, 0.5h, and 0.8h depth. National Water Quality Standards for Malaysia (NWQS) and Water Quality were used to evaluate Bera Lake quality based on previous and resultant data. Vertical water quality analysis revealed a clear stratification in Bera Lake water profile in terms of temperature, dissolved oxygen, chloride (Cl(-)), nitrate (NO(3)), pH and specific conductivity (EC) parameters. Results clearly demonstrate the important role of land use changes since 1972 in the physico-chemical condition of water quality at Bera Lake. Classifications of water quality before and after land development project were calculated as class II and class V, respectively. A long-term and comprehensive monitoring of water quality assessment is recommended in order to reach plan of sustainable water resources use with conservation approach.
    Matched MeSH terms: Temperature
  2. Cross-linked beads of activated oil palm ash zeolite/chitosan composite as a bio-adsorbent for the removal of methylene blue and acid blue 29 dyes
    Khanday WA, Asif M, Hameed BH
    Int J Biol Macromol, 2017 Feb;95:895-902.
    PMID: 27789331 DOI: 10.1016/j.ijbiomac.2016.10.075
    Cross-linked beads of activated oil palm ash zeolite/chitosan (Z-AC/C) composite were prepared through the hydrothermal treatment of NaOH activated oil palm ash followed by beading with chitosan. The effects of initial dye concentration (50-400mg/L), temperature (30°C-50°C) and pH (3-13) on batch adsorption of methylene blue (MB) and acid blue 29 (AB29) were studied. Adsorption of both dyes was better described by Pseudo-second-order kinetics and Freundlich isotherm model. The maximum adsorption capacities of Z-AC/C were 151.51, 169.49, and 199.20mg/g for MB and 212.76, 238.09, and 270.27mg/g for AB29 at 30°C, 40°C, and 50°C, respectively.
    Matched MeSH terms: Temperature
  3. Fulltext Novel biphenyl ester derivatives as tyrosinase inhibitors: Synthesis, crystallographic, spectral analysis and molecular docking studies
    Kwong HC, Chidan Kumar CS, Mah SH, Chia TS, Quah CK, Loh ZH, et al.
    PLoS One, 2017;12(2):e0170117.
    PMID: 28241010 DOI: 10.1371/journal.pone.0170117
    Biphenyl-based compounds are clinically important for the treatments of hypertension and inflammatory, while many more are under development for pharmaceutical uses. In the present study, a series of 2-([1,1'-biphenyl]-4-yl)-2-oxoethyl benzoates, 2(a-q), and 2-([1,1'-biphenyl]-4-yl)-2-oxoethyl pyridinecarboxylate, 2(r-s) were synthesized by reacting 1-([1,1'-biphenyl]-4-yl)-2-bromoethan-1-one with various carboxylic acids using potassium carbonate in dimethylformamide at ambient temperature. Single-crystal X-ray diffraction studies revealed a more closely packed crystal structure can be produced by introduction of biphenyl moiety. Five of the compounds among the reported series exhibited significant anti-tyrosinase activities, in which 2p, 2r and 2s displayed good inhibitions which are comparable to standard inhibitor kojic acid at concentrations of 100 and 250 μg/mL. The inhibitory effects of these active compounds were further confirmed by computational molecular docking studies and the results revealed the primary binding site is active-site entrance instead of inner copper binding site which acted as the secondary binding site.
    Matched MeSH terms: Temperature
  4. Cellulose nanocomposite films with in situ generated silver nanoparticles using Cassia alata leaf extract as a reducing agent
    Sivaranjana P, Nagarajan ER, Rajini N, Jawaid M, Rajulu AV
    Int J Biol Macromol, 2017 Jun;99:223-232.
    PMID: 28237574 DOI: 10.1016/j.ijbiomac.2017.02.070
    Cotton linters were dissolved in aq. (8% LiOH+15% urea) that was pre-cooled to -12.5°C. Using this solution cellulose gel films were prepared by regeneration method with ethyl alcohol as a coagulant. These wet films were diffused with 10wt% Cassia alata leaf extract that acted as a reducing agent. The leaf extract diffused cellulose wet films were used as the matrix. The wet matrix films were dipped individually in lower concentrated 1-5mM aq.AgNO3 source solutions in the presence of sunlight and allowed the solutions to react with the diffused leaf extract reducing agent which in situ generated the silver nanoparticles (AgNPs) inside the films as well as in the source solution. The AgNPs formed in the source solution were observed by transmission electron microscope (TEM) and scanning electron microscope (SEM) while those formed in situ the films were observed by SEM and the particle size distribution was determined. The cellulose/AgNP composite films showed good antibacterial activity against Escherichia coli bacteria. These nanocomposite films were also characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA) and tensile tests. At temperatures below 300°C, the thermal stability of the nanocomposite films was lower than that of the matrix due to the catalytic effect of AgNPs. The nanocomposite films also possessed good tensile properties. The ecofriendly cellulose/AgNP composite films with good antibacterial activity and tensile properties can be considered for medical applications like dressing materials.
    Matched MeSH terms: Temperature
  5. Influence of high temperature on the performance of aerobic granular sludge in biological treatment of wastewater
    Ab Halim MH, Nor Anuar A, Abdul Jamal NS, Azmi SI, Ujang Z, Bob MM
    J Environ Manage, 2016 Dec 15;184(Pt 2):271-280.
    PMID: 27720606 DOI: 10.1016/j.jenvman.2016.09.079
    The effect of temperature on the efficiency of organics and nutrients removal during the cultivation of aerobic granular sludge (AGS) in biological treatment of synthetic wastewater was studied. With this aim, three 3 L sequencing batch reactors (SBRs) with influent loading rate of 1.6 COD g (L d)(-1) were operated at different high temperatures (30, 40 and 50 °C) for simultaneous COD, phosphate and ammonia removal at a complete cycle time of 3 h. The systems were successfully started up and progressed to steady state at different cultivation periods. The statistical comparison of COD, phosphate and ammonia for effluent from the three SBRs revealed that there was a significant difference between groups of all the working temperatures of the bioreactors. The AGS cultivated at different high temperatures also positively correlated with the accumulation of elements including carbon, oxygen, phosphorus, silicon, iron, aluminium, calcium and magnesium that played important roles in the granulation process.
    Matched MeSH terms: Temperature
  6. Kinetics, thermodynamics, equilibrium isotherms, and reusability studies of cationic dye adsorption by magnetic alginate/oxidized multiwalled carbon nanotubes composites
    Boukhalfa N, Boutahala M, Djebri N, Idris A
    Int J Biol Macromol, 2019 Feb 15;123:539-548.
    PMID: 30447356 DOI: 10.1016/j.ijbiomac.2018.11.102
    Magnetic beads (AO-γ-Fe2O3) of alginate (A) impregnated with citrate coated maghemite nanoparticles (γ-Fe2O3) and oxidized multiwalled carbon nanotubes (OMWCNTs) were synthesized and used as adsorbent for the removal of methylene blue from water. The XRD analysis revealed that the diameter of γ-Fe2O3 is 10.24 nm. The mass saturation magnetization of AO-γ-Fe2O3 and γ-Fe2O3 were found to be 27.16 and 42.63 emu·g-1, respectively. The adsorption studies revealed that the data of MB isotherm were well fitted to the Freundlich model. The Langmuir isotherm model exhibited a maximum adsorption capacity of 905.5 mg·g-1. The adsorption was very dependent on initial concentration, adsorbent dose, and temperature. The beads exhibited high adsorption stability in large domain of pH (4-10). The thermodynamic parameters determined at 283, 293, 303, and 313 K revealed that the adsorption occurring was spontaneous and endothermic in nature. Adsorption kinetic data followed the intraparticle diffusion model. The AO-γ-Fe2O3 beads were used for six cycles without significant adsorptive performance loss. Therefore, the eco-friendly prepared AO-γ-Fe2O3 beads were considered as highly recyclable and efficient adsorbent for methylene blue as they can be easily separated from water after treatment.
    Matched MeSH terms: Temperature
  7. Fulltext Characterization of Ternary Blends of Vegetable Oils with Optimal ω-6/ω-3 Fatty Acid Ratios
    Nehdi IA, Hadj-Kali MK, Sbihi HM, Tan CP, Al-Resayes SI
    J Oleo Sci, 2019;68(11):1041-1049.
    PMID: 31695014 DOI: 10.5650/jos.ess19111
    An optimal ratio of omega-6 to omega-3 (ω-6/ω-3) polyunsaturated fatty acids (PUFA) in the diet prevents the pathogenesis of many inflammatory diseases. This study aimed to synthesize and characterize ternary oil blends with optimal ω-6/ω-3 ratios using olive (OL), sunflower (SU), and cress (CR) oils. The oxidative stability, thermal profile, fatty acid (FA) and tocopherol compositions, and the physicochemical properties of the blends were used to determine their quality. Oil mixtures were prepared with 2, 3, 4, and 5 ω-6/ω-3 ratios. FA composition and tocopherol content were the most important factors affecting the oxidation and thermal stabilities of the oils. All oil mixtures showed good quality indices. Thus, synthetized oil blends with high oxidative stability, high antioxidant content, optimal ω-6/ω-3 ratios, and recommended FA compositions can influence human health. The composition of healthy oil blends with optimal ω-6/ω-3 ratios was expressed mathematically and depicted graphically in a ternary diagram.
    Matched MeSH terms: Temperature
  8. Tunable Schiff's base-cross-linked chitosan composite for the removal of reactive red 120 dye: Adsorption and mechanism study
    Jawad AH, Mubarak NSA, Abdulhameed AS
    Int J Biol Macromol, 2020 Jan 01;142:732-741.
    PMID: 31760013 DOI: 10.1016/j.ijbiomac.2019.10.014
    In this study, tunable Schiff's base-cross-linked chitosan-glutaraldehyde (CS-GLA) was modified and applied to remove reactive red 120 (RR120) dye from an aqueous solution. Different ratios of TiO2 nanoparticles, such as 25% TiO2 nanoparticles (CS-GLA/TNC-25) and 50% TiO2 nanoparticles (CS-GLA/TNC-50), were loaded into the CS-GLA's molecular structure. The adsorptive properties of CS-GLA, CS-GLA/TNC-25, and CS-GLA/TNC-50 for the RR120 dye in the aqueous solution were evaluated. CS-GLA/TNC-25 exhibited the best adsorptive property possibly because of the perfect balancing between the surface area and available amine (NH2) groups in the composite formulation. The impact of adsorption key parameters, such as adsorbent dosage (0.01-1.2 g), RR120 dye concentration (30-400 mg/L), solution pH (3-12), and contact time (0-400 min) were explored by batch adsorption mode. The adsorption was well described by the Freundlich model and pseudo-second order kinetic model. The adsorption capacity of CS-GLA/TNC-25 for RR120 dye was 103.1 mg/g at 303K. The adsorption mechanism of RR120 on the CS-GLA/TNC-25 surface can be assigned to various interactions, such as electrostatic attraction, n-π stacking, and H-bonding. Results indicate the potential application of CS-GLA/TNC-25 as environment-friendly biosorbent for removing acid and/or textile dyes, such as RR120, from aqueous environments.
    Matched MeSH terms: Temperature
  9. Fulltext Surface-Engineered Super-Paramagnetic Iron Oxide Nanoparticles For Chromium Removal
    Samrot AV, Sahithya CS, Selvarani A J, Pachiyappan S, Kumar S S
    Int J Nanomedicine, 2019;14:8105-8119.
    PMID: 31632021 DOI: 10.2147/IJN.S214236
    Background: Super-paramagnetic iron oxide nanoparticles (SPIONs) are widely used metal nanoparticles for various applications for its magnetic property and biocompatibility. In recent years, pollution of our environment especially with heavy metals in waterbodies has become a major threat and has left us very minimal sources of freshwater to drink. SPIONs or surface modified SPIONs can be used to remove these heavy metals.

    Methods: SPIONs were synthesized by co-precipitation method and further coated with a biopolymer, chitosan. Chromium solution was treated with the synthesized SPIONs to study the efficiency of chromium removal by surface adsorption. Later, the adsorption was analysed by direct and indirect analysis methods using UV-VIS spectrophotometry and isotherm studies.

    Results: Stable chitosan-coated SPIONs were synthesized and they adsorbed chromium better than the uncoated SPIONs, where it was adsorbing up to 100 ppm. Adsorption was found to be increasing with decrease in pH.

    Conclusion: The surface-modified SPIONs expressed cumulative adsorption action. Even after the adsorption studies, chitosan-coated SPIONs were possessing magnetic property. Thus, the surface-modified SPIONs can become an ideal nanotechnology tool to remove the chromium from groundwater.

    Matched MeSH terms: Temperature
  10. Respiratory health among office workers in Malaysia and endotoxin and (1,3)-β-glucan in office dust
    Lim FL, Hashim Z, Than LTL, Md Said S, Hashim JH, Norbäck D
    Int J Tuberc Lung Dis, 2019 11 01;23(11):1171-1177.
    PMID: 31718753 DOI: 10.5588/ijtld.18.0668
    OBJECTIVE: To examine the associations between endotoxin and (1,3)-β-glucan concentrations in office dust and respiratory symptoms and airway inflammation among 695 office workers in Malaysia.METHODS: Health data were collected using a questionnaire, sensitisation testing and measurement of fractional exhaled nitric oxide (FeNO). Indoor temperature, relative air humidity (RH) and carbon dioxide (CO₂) were measured in the offices and settled dust was vacuumed and analysed for endotoxin and (1,3)-β-glucan concentrations. Associations were analysed by two level multiple logistic regression.RESULTS: Overall, 9.6% of the workers had doctor-diagnosed asthma, 15.5% had wheeze, 18.4% had daytime attacks of breathlessness and 25.8% had elevated FeNO (≥25 ppb). The median levels in office dust were 11.3 EU/mg endotoxin and 62.9 ng/g (1,3)-β-glucan. After adjusting for personal and home environment factors, endotoxin concentration in dust was associated with wheeze (P = 0.02) and rhinoconjunctivitis (P = 0.007). The amount of surface dust (P = 0.04) and (1,3)-β-glucan concentration dust (P = 0.03) were associated with elevated FeNO.CONCLUSION: Endotoxin in office dust could be a risk factor for wheeze and rhinoconjunctivitis among office workers in mechanically ventilated offices in a tropical country. The amount of dust and (1,3)-β-glucan (a marker of indoor mould exposure) were associated with Th2 driven airway inflammation.
    Matched MeSH terms: Temperature
  11. Fulltext Hepatoprotective Effects of Morinda citrifolia Leaf Extract on Ovariectomized Rats Fed with Thermoxidized Palm Oil Diet: Evidence at Histological and Ultrastructural Level
    Chong CLG, Hussan F, Othman F
    Oxid Med Cell Longev, 2019;2019:9714302.
    PMID: 31827717 DOI: 10.1155/2019/9714302
    Morinda citrifolia (Rubiaceae) or Noni was previously reported to have leaf with broad therapeutic property whereas the fruit was rarely described as medicinal. Ironically, extensive research and review has been done on the fruit and little was known about the therapeutic activity of the leaf as a medicinal food. The aim of this study was to investigate the therapeutic effects of Morinda citrifolia (MC) ethanolic leaf extract on the hepatic structure and function in postmenopausal rats fed with thermoxidized palm oil (TPO) diet. Thirty eight female Sprague Dawley rats were divided into five groups: sham (Sham), ovariectomized (OVX), ovariectomized and treated with simvastatin 10 mg/kg (OVX+ST), ovariectomized and supplemented with low dose MC 500 mg/kg (OVX+MCLD), and ovariectomized and supplemented with high dose MC 1000 mg/kg (OVX+MCHD). All the ovariectomized groups were fed with TPO diet whereas the Sham group was fed with normal diet. Consumption of TPO diet in postmenopausal rats resulted in obesity, significantly elevated (P < 0.05) liver oxidative stress marker; malondialdehyde (MDA), diffuse microvesicular steatosis, and defective mitochondria. Treatment with MC leaf extract prevented hepatic steatosis by significantly increasing (P < 0.05) the liver antioxidant enzyme SOD and GPx, significantly increasing (P < 0.05) ALP, decreasing liver lipids infiltration, preventing mitochondrial damage, and overall maintaining the normal liver histology and ultrastructure. In conclusion, we provided detailed histological and ultrastructural evidence showing hepatoprotective effects of MC leaf extract through its antioxidant mechanism.
    Matched MeSH terms: Hot Temperature
  12. Synthesis and characterization of choline-fatty-acid-based ionic liquids: A new biocompatible surfactant
    Ali MK, Moshikur RM, Wakabayashi R, Tahara Y, Moniruzzaman M, Kamiya N, et al.
    J Colloid Interface Sci, 2019 Sep 01;551:72-80.
    PMID: 31075635 DOI: 10.1016/j.jcis.2019.04.095
    Ionic liquid (IL) surfactants have attracted great interest as promising substitutes for conventional surfactants owing to their exceptional and favorable physico-chemical properties. However, most IL surfactants are not eco-friendly and form unstable micelles, even when using a high concentration of the surfactant. In this study, we prepared a series of halogen-free and biocompatible choline-fatty-acid-based ILs with different chain lengths and degrees of saturation, and we then investigated their micellar properties in aqueous solutions. Characterization of the synthesized surface-active ILs (SAILs) was performed by 1H and 13C nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and elemental analysis. The surface-active properties of the SAILs were investigated by tensiometry, conductometry, and dynamic light scattering measurements. The critical micelle concentration of the SAILs was found to be 2-4 times lower than those of conventional surfactants. The thermodynamic properties of micellization (ΔG0m, ΔH0m, and ΔS0m) indicate that the micellization process of the SAILs is spontaneous, stable, and entropy-driven at room temperature. The cytotoxicity of the SAILs was evaluated using mammalian cell line NIH 3T3. Importantly, [Cho][Ole] shows lower toxicity than the analogous ILs with conventional surfactants. These results clearly suggest that these environmentally friendly SAILs can be used as a potential alternative to conventional ILs for various purposes, including biological applications.
    Matched MeSH terms: Temperature
  13. New magnetic Schiff's base-chitosan-glyoxal/fly ash/Fe3O4 biocomposite for the removal of anionic azo dye: An optimized process
    Malek NNA, Jawad AH, Abdulhameed AS, Ismail K, Hameed BH
    Int J Biol Macromol, 2020 Mar 01;146:530-539.
    PMID: 31917215 DOI: 10.1016/j.ijbiomac.2020.01.020
    In this study, a new magnetic Schiff's base-chitosan-glyoxal/fly ash/Fe3O4 biocomposite (Chi-Gly/FA/Fe3O4) was successfully synthesized by direct compositing of magnetic chitosan (Chi) with fly ash (FA) powder particles, and followed by Schiff's base formation via cross-linking reaction with glyoxal (Gly). Various techniques such as BET, XRD, FTIR, and SEM-EDX were utilized to characterize of Chi-Gly/FA/Fe3O4 biocomposite. The effectiveness of Chi-Gly/FA/Fe3O4 as an adsorbent was evaluated for the removal anionic azo dye such as reactive orange 16 (RO16) from aqueous environment. The effect of adsorption process parameters namely adsorbent dose (A: 0.02-0.1 g), solution pH (B: 4-10), temperature (C: 30-50 °C), and contact time (D: 5-20 min) were optimized via Box-Behnken design (BBD) in response surface methodology (RSM). The adsorption process followed the pseudo-second order (PSO) kinetic, and Freundlich isotherm models. The maximum adsorption capacity of Chi-Gly/FA/Fe3O4 biocomposite for RO16 dye was recorded to be 112.5 mg/g at 40 °C. The RO16 dye adsorption mechanism was attributed to various interactions such as electrostatic, n-π, H-bonding, and Yoshida H-bonding. Furthermore, the Chi-Gly/FA/Fe3O4 biocomposite exhibited a high ability to separate from the aqueous solution after adsorption process by external magnetic field.
    Matched MeSH terms: Temperature
  14. Comprehensive studies on optimization of cellulase and xylanase production by a local indigenous fungus strain via solid state fermentation using oil palm frond as substrate
    Tai WY, Tan JS, Lim V, Lee CK
    Biotechnol Prog, 2019 05;35(3):e2781.
    PMID: 30701709 DOI: 10.1002/btpr.2781
    The high cost of cellulases remains the most significant barrier to the economical production of bio-ethanol from lignocellulosic biomass. The goal of this study was to optimize cellulases and xylanase production by a local indigenous fungus strain (Aspergillus niger DWA8) using agricultural waste (oil palm frond [OPF]) as substrate. The enzyme production profile before optimization indicated that the highest carboxymethyl cellulose (CMCase), filter paper (FPase), and xylanase activities of 1.06 U/g, 2.55 U/g, and 2.93 U/g were obtained on day 5, day 4, and day 5 of fermentation, respectively. Response surface methodology was used to study the effects of several key process parameters in order to optimize cellulase production. Of the five physical and two chemical factors tested, only moisture content of 75% (w/w) and substrate amount of 2.5 g had statistically significant effect on enzymes production. Under optimized conditions of 2.5 g of substrate, 75% (w/w) moisture content, initial medium of pH 4.5, 1 × 106 spores/mL of inoculum, and incubation at ambient temperature (±30°C) without additional carbon and nitrogen, the highest CMCase, FPase, and xylanase activities obtained were 2.38 U/g, 2.47 U/g, and 5.23 U/g, respectively. Thus, the optimization process increased CMCase and xylanase production by 124.5 and 78.5%, respectively. Moreover, A. niger DWA8 produced reasonably good cellulase and xylanase titers using OPF as the substrate when compared with previous researcher finding. The enzymes produced by this process could be further use to hydrolyze biomass to generate reducing sugars, which are the feedstock for bioethanol production.
    Matched MeSH terms: Temperature
  15. Molecular characterization and enzyme inhibition studies of NADP+- farnesol dehydrogenase from diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae)
    Zifruddin AN, Mohamad-Khalid KA, Suhaimi SA, Mohamed-Hussein ZA, Hassan M
    Biosci Biotechnol Biochem, 2021 Jun 24;85(7):1628-1638.
    PMID: 33890631 DOI: 10.1093/bbb/zbab072
    Juvenile hormone III (JH III) plays an important role in insect reproduction, development, and behavior. The second branch of JH III production includes oxidation of farnesol to farnesal by farnesol dehydrogenase. This study reported the identification and characterization of Plutella xylostella farnesol dehydrogenase (PxFoLDH). Our results showed that PxFoLDH belongs to the short-chain dehydrogenase/reductase superfamily, consisting of a single domain with a structurally conserved Rossman fold, an NAD(P) (H)-binding region and a structurally diverse C-terminal region. The purified enzyme displayed maximum activity at 55$\ $°C with pH 9.5 and was stable in the temperature below 70$\ ^\circ $C. PxFoLDH was determined to be a monomer with a relative molecular weight of 27 kDa and highly specific for trans, trans-farnesol, and NADP+. Among analog inhibitors tested, farnesyl acetate was the most effective inhibitor with the lowest Ki value of 0.02 µm. Our findings showed this purified enzyme may represent as NADP+-farnesol dehydrogenase.
    Matched MeSH terms: Temperature
  16. Fulltext Psychrotolerant Mesorhizobium sp. Isolated from Temperate and Cold Desert Regions Solubilizes Potassium and Produces Multiple Plant Growth Promoting Metabolites
    Baba ZA, Hamid B, Sheikh TA, Alotaibi SH, El Enshasy HA, Ansari MJ, et al.
    Molecules, 2021 Sep 23;26(19).
    PMID: 34641302 DOI: 10.3390/molecules26195758
    Soil potassium (K) supplement depends intensively on the application of chemical fertilizers, which have substantial harmful environmental effects. However, some bacteria can act as inoculants by converting unavailable and insoluble K forms into plant-accessible forms. Such bacteria are an eco-friendly approach for enhancing plant K absorption and consequently reducing utilization of chemical fertilization. Therefore, the present research was undertaken to isolate, screen, and characterize the K solubilizing bacteria (KSB) from the rhizosphere soils of northern India. Overall, 110 strains were isolated, but only 13 isolates showed significant K solubilizing ability by forming a halo zone on solid media. They were further screened for K solubilizing activity at 0 °C, 1 °C, 3 °C, 5 °C, 7 °C, 15 °C, and 20 °C for 5, 10, and 20 days. All the bacterial isolates showed mineral K solubilization activity at these different temperatures. However, the content of K solubilization increased with the upsurge in temperature and period of incubation. The isolate KSB (Grz) showed the highest K solubilization index of 462.28% after 48 h of incubation at 20 °C. The maximum of 23.38 µg K/mL broth was solubilized by the isolate KSB (Grz) at 20 °C after 20 days of incubation. Based on morphological, biochemical, and molecular characterization (through the 16S rDNA approach), the isolate KSB (Grz) was identified as Mesorhizobium sp. The majority of the strains produced HCN and ammonia. The maximum indole acetic acid (IAA) (31.54 µM/mL) and cellulase (390 µM/mL) were produced by the isolate KSB (Grz). In contrast, the highest protease (525.12 µM/mL) and chitinase (5.20 µM/mL) activities were shown by standard strain Bacillus mucilaginosus and KSB (Gmr) isolate, respectively.
    Matched MeSH terms: Temperature
  17. Fly ash modified magnetic chitosan-polyvinyl alcohol blend for reactive orange 16 dye removal: Adsorption parametric optimization
    Malek NNA, Jawad AH, Ismail K, Razuan R, ALOthman ZA
    Int J Biol Macromol, 2021 Oct 31;189:464-476.
    PMID: 34450144 DOI: 10.1016/j.ijbiomac.2021.08.160
    A magnetic biocomposite blend of chitosan-polyvinyl alcohol/fly ash (m-Cs-PVA/FA) was developed by adding fly ash (FA) microparticles into the polymeric matrix of magnetic chitosan-polyvinyl alcohol (m-Cs-PVA). The effectiveness of m-Cs-PVA/FA as an adsorbent to remove textile dye (reactive orange 16, RO16) from aquatic environment was evaluated. The optimum adsorption key parameters and their significant interactions were determined by Box-Behnken Design (BBD). The analysis of variance (ANOVA) indicates the significant interactions can be observed between m-Cs-PVA/FA dose with solution pH, and m-Cs-PVA/FA dose with working temperature. Considering these significant interactions, the highest removal of RO16 (%) was found 90.3% at m-Cs-PVA/FA dose (0.06 g), solution pH (4), working temperature (30 °C), and contact time (17.5 min). The results of adsorption kinetics revealed that the RO16 adsorption was better described by the pseudo-second-order model. The results of adsorption isotherm indicated a multilayer adsorption process as well described by Freundlich model with maximum adsorption capacity of 123.8 mg/g at 30 °C. An external magnetic field can be easily applied to recover the adsorbent (m-Cs-PVA/FA). The results supported that the synthesized m-Cs-PVA/FA presents itself as an effective and promising adsorbent for textile dye with preferable adsorption capacity and separation ability during and after the adsorption process.
    Matched MeSH terms: Temperature
  18. Optimization of L-asparaginase production from endophytic Fusarium proliferatum using OFAT and RSM and its cytotoxic evaluation
    Yap LS, Lee WL, Ting ASY
    J Microbiol Methods, 2021 12;191:106358.
    PMID: 34743930 DOI: 10.1016/j.mimet.2021.106358
    L-asparaginase from endophytic Fusarium proliferatum (isolate CCH, GenBank accession no. MK685139) isolated from the medicinal plant Cymbopogon citratus (Lemon grass), was optimized for its L-asparaginase production and its subsequent cytotoxicity towards Jurkat E6 cell line. The following factors were optimized; carbon source and concentration, nitrogen source and concentration, incubation period, temperature, pH and agitation rate. Optimization of L-asparaginase production was performed using One-Factor-At-A-Time (OFAT) and Response surface methodology (RSM) model. The cytotoxicity of the crude enzyme from isolate CCH was tested on leukemic Jurkat E6 cell line. The optimization exercise revealed that glucose concentration, nitrogen source, L-asparagine concentration and temperature influenced the L-asparaginase production of CCH. The optimum condition suggested using OFAT and RSM results were consistent. As such, the recommended conditions were 0.20% of glucose, 0.99% of L-asparagine and 5.34 days incubation at 30.50 °C. The L-asparaginase production of CCH increased from 16.75 ± 0.76 IU/mL to 22.42 ± 0.20 IU/mL after optimization. The cytotoxicity of the crude enzyme on leukemic Jurkat cell line recorded IC50 value at 33.89 ± 2.63% v/v. To conclude, the enzyme extract produced from Fusarium proliferatum under optimized conditions is a potential alternative resource for L-asparaginase.
    Matched MeSH terms: Temperature
  19. The Effects of One Amino Acid Substitutions at the C-Terminal Region of Thermostable L2 Lipase by Computational and Experimental Approach
    Sani HA, Shariff FM, Rahman RNZRA, Leow TC, Salleh AB
    Mol Biotechnol, 2018 Jan;60(1):1-11.
    PMID: 29058211 DOI: 10.1007/s12033-017-0038-3
    The substitutions of the amino acid at the predetermined critical point at the C-terminal of L2 lipase may increase its thermostability and enzymatic activity, or even otherwise speed up the unfolding of the protein structure. The C-terminal of most proteins is often flexible and disordered. However, some protein functions are directly related to flexibility and play significant role in enzyme reaction. The critical point for mutation of L2 lipase structure was predicted at the position 385 of the L2 sequence, and the best three mutants were determined based on I-Mutant2.0 software. The best three mutants were S385E, S385I and S385V. The effects of the substitution of the amino acids at the critical point were analysed with molecular dynamics simulation by using Yet Another Scientific Artificial Reality Application software. The predicted mutant L2 lipases were found to have lower root mean square deviation value as compared to L2 lipase. It was indicated that all the three mutants had higher compactness in the structure, consequently enhanced the stability. Root mean square fluctuation analysis showed that the flexibility of L2 lipase was reduced by mutations. Purified S385E lipase had an optimum temperature of 80 °C in Tris-HCl pH 8. The highest enzymatic activity of purified S385E lipase was obtained at 80 °C temperature in Tris-HCl pH 8, while for L2 lipase it was at 70 °C in Glycine-NaOH pH 9. The thermal stability of S385V lipase was enhanced as compared to other protein since that the melting point (T m) value was at 85.96 °C. S385I lipase was more thermostable compared to recombinant L2 lipase and other mutants at temperature 60 °C within 16 h preincubation.
    Matched MeSH terms: Temperature
  20. Green Nanotechnology for Synthesis and characterization of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) nanoparticles for sustained bortezomib release using supercritical CO2 assisted particle formation combined with electrodeposition
    Demirdöğen RE, Emen FM, Ocakoglu K, Murugan P, Sudesh K, Avşar G
    Int J Biol Macromol, 2018 Feb;107(Pt A):436-445.
    PMID: 28888547 DOI: 10.1016/j.ijbiomac.2017.09.011
    Carbon dioxide assisted particle formation combined with electrospraying using supercritical CO2 (scCO2) as an aid (Carbon Dioxide Assisted Nebulization-Electrodeposition, CAN-ED) was used to produce Bortezomib loaded poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) P(3HB-co-3HHx) nanoparticles for sustained release. The morphology and structure of the prepared nanoparticles were investigated by SEM, TEM and FT-IR spectroscopy. Average diameter of particles obtained was 155nm and the average core sizes of P(3HB-co-3HHx) nanoparticles were between 6 and 13nm. The drug loading capacity, drug release and stability of Bortezomib loaded P(3HB-co-3HHx) nanoparticles were analyzed. The maximum loading capacity was achieved at pH=6.0 in phosphate buffer (K2HPO4/KH2PO4). It was found that temperature did not affect the stability of Bortezomib loaded nanoparticles and it was good both at 37°C and 4°C. This study pointed out that CAN-ED is a green method to produce P(3HB-co-3HHx) nanoparticles for pH responsive targeting of Bortezomib especially to parts of the body where size exclusion is not crucial.
    Matched MeSH terms: Temperature
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links