Displaying publications 1821 - 1840 of 2920 in total

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  1. Cloning, Production and Characterization of a Glycoside Hydrolase Family 7 Enzyme from the Gut Microbiota of the Termite Coptotermes curvignathus
    Woon JS, King PJH, Mackeen MM, Mahadi NM, Wan Seman WMK, Broughton WJ, et al.
    Mol Biotechnol, 2017 Jul;59(7):271-283.
    PMID: 28573450 DOI: 10.1007/s12033-017-0015-x
    Coptotermes curvignathus is a termite that, owing to its ability to digest living trees, serves as a gold mine for robust industrial enzymes. This unique characteristic reflects the presence of very efficient hydrolytic enzyme systems including cellulases. Transcriptomic analyses of the gut of C. curvignathus revealed that carbohydrate-active enzymes (CAZy) were encoded by 3254 transcripts and that included 69 transcripts encoding glycoside hydrolase family 7 (GHF7) enzymes. Since GHF7 enzymes are useful to the biomass conversion industry, a gene encoding for a GHF7 enzyme (Gh1254) was synthesized, sub-cloned and expressed in the methylotrophic yeast Pichia pastoris. Expressed GH1254 had an apparent molecular mass of 42 kDa, but purification was hampered by its low expression levels in shaken flasks. To obtain more of the enzyme, GH1254 was produced in a bioreactor that resulted in a fourfold increase in crude enzyme levels. The purified enzyme was active towards soluble synthetic substrates such as 4-methylumbelliferyl-β-D-cellobioside, 4-nitrophenyl-β-D-cellobioside and 4-nitrophenyl-β-D-lactoside but was non-hydrolytic towards Avicel or carboxymethyl cellulose. GH1254 catalyzed optimally at 35 °C and maintained 70% of its activity at 25 °C. This enzyme is thus potentially useful in food industries employing low-temperature conditions.
    Matched MeSH terms: Temperature
  2. Effect of degree of deacetylation of chitosan on adsorption capacity and reusability of chitosan/polyvinyl alcohol/TiO2 nano composite
    Habiba U, Joo TC, Siddique TA, Salleh A, Ang BC, Afifi AM
    Int J Biol Macromol, 2017 Nov;104(Pt A):1133-1142.
    PMID: 28690164 DOI: 10.1016/j.ijbiomac.2017.07.007
    The chitosan/polyvinyl alcohol/TiO2 composite was synthesized. Two different degrees of deacetylation of chitosan were prepared by hydrolysis to compare the effectiveness of them. The composite was analyzed via field emission scanning electron microscopy, Fourier transform infrared, X-ray diffraction, thermal gravimetric analysis, weight loss test and adsorption study. The FTIR and XRD results proved the interaction among chitosan, PVA and TiO2 without any chemical reaction. It was found that, chitosan with higher degree of deacetylation has better stability. Furthermore, it also showed that higher DD of chitosan required less time to reach equilibrium for methyl orange. The adsorption followed the pseudo-second-order kinetic model. The Langmuir and Freundlich isotherm models were fitted well for isotherm study. Adsorption capacity was higher for the composite containing chitosan with higher DD. The dye removal rate was independent of the dye's initial concentration. The adsorption capacity was increased with temperature and it was found from reusability test that the composite containing chitosan with higher DD is more reusable. It was notable that adsorption capacity was even after 15 runs. Therefore, chitosan/PVA/TiO2 composite can be a very useful material for dye removal.
    Matched MeSH terms: Temperature
  3. Fulltext Effects of Physiochemical Factors on Prokaryotic Biodiversity in Malaysian Circumneutral Hot Springs
    Chan CS, Chan KG, Ee R, Hong KW, Urbieta MS, Donati ER, et al.
    Front Microbiol, 2017;8:1252.
    PMID: 28729863 DOI: 10.3389/fmicb.2017.01252
    Malaysia has a great number of hot springs, especially along the flank of the Banjaran Titiwangsa mountain range. Biological studies of the Malaysian hot springs are rare because of the lack of comprehensive information on their microbial communities. In this study, we report a cultivation-independent census to describe microbial communities in six hot springs. The Ulu Slim (US), Sungai Klah (SK), Dusun Tua (DT), Sungai Serai (SS), Semenyih (SE), and Ayer Hangat (AH) hot springs exhibit circumneutral pH with temperatures ranging from 43°C to 90°C. Genomic DNA was extracted from environmental samples and the V3-V4 hypervariable regions of 16S rRNA genes were amplified, sequenced, and analyzed. High-throughput sequencing analysis showed that microbial richness was high in all samples as indicated by the detection of 6,334-26,244 operational taxonomy units. In total, 59, 61, 72, 73, 65, and 52 bacterial phyla were identified in the US, SK, DT, SS, SE, and AH hot springs, respectively. Generally, Firmicutes and Proteobacteria dominated the bacterial communities in all hot springs. Archaeal communities mainly consisted of Crenarchaeota, Euryarchaeota, and Parvarchaeota. In beta diversity analysis, the hot spring microbial memberships were clustered primarily on the basis of temperature and salinity. Canonical correlation analysis to assess the relationship between the microbial communities and physicochemical variables revealed that diversity patterns were best explained by a combination of physicochemical variables, rather than by individual abiotic variables such as temperature and salinity.
    Matched MeSH terms: Temperature
  4. Fulltext Response surface optimization of ultrasonic-assisted extraction of carotenoids from oil palm (Elaeis guineensis Jacq.) fronds
    Ofori-Boateng C, Lee KT
    Food Sci Nutr, 2013 05;1(3):209-221.
    PMID: 29387349 DOI: 10.1002/fsn3.22
    Oil palm (Elaeis guineensis Jacq.) fronds (OPF) are the most abundant oil palm solid wastes that are generated during oil palm agriculture and harvest. Palm oil and some other palm wastes have been reported to contain high concentrations of carotenoids with vital bioactive properties. However, the extraction and quantification of carotenoids from OPF have not been reported. In this study, ultrasonic-assisted extraction, HPLC-FLD for quantification, and response surface methodology (RSM) for optimization of β-carotene, lutein, and zeaxanthin from OPF extracts were investigated. The effects of extraction temperature (X1: 30-70°C), extraction time (X2: 10-50 min), and solvent-sample ratio (X3: 10-50 mL/g) on the recovery of β-carotene (Y1), lutein (Y2), and zeaxanthin (Y3) were investigated using three-level Box-Behnken design (BBD) experiment. At a desirability of 1, the optimum extraction conditions for β-carotene (30.14°C, 37.11 min, and 23.18 mL/g), lutein (30.00°C, 39.09 min, and 19.24 mL/g), and zeaxanthin (30.09°C, 36.76 min, and 22.38 mL/g) yielded carotenoid concentrations of 17.95 μg/g dry weight (DW), 261.99 μg/g DW, and 29.99 μg/g DW, respectively.
    Matched MeSH terms: Temperature
  5. Microencapsulated Lactobacillus plantarum LAB12 Showed No Sign of Acute or Sub-chronic Toxicity In Vivo
    Fareez IM, Lim SM, Ramasamy K
    Probiotics Antimicrob Proteins, 2019 06;11(2):447-459.
    PMID: 30003409 DOI: 10.1007/s12602-018-9442-7
    Lactic acid bacteria (LAB) with probiotic properties are useful options for prophylactic and therapeutic applications against gastrointestinal diseases. The safety of probiotics should, however, be verified before incorporation into food or drinks. The present study had encapsulated Lactobacillus plantarum LAB12 within microcapsules that could withstand extremely high temperature (up to 100 °C) during pelletisation. The microencapsulated LAB12 were then tested for their acute (single dosing) and sub-chronic (a 90-day feeding) toxicity. For acute toxicity study, six male Sprague-Dawley rats were being administered with a single dose of freeze-dried microencapsulated LAB12 at 11 log CFU/kg BW through oral gavage. No clear treatment-related effects were observed after 14 days. For sub-chronic toxicity study, rodents were randomly divided into four groups (6 rats/sex/group) and treated with 0, 8, 9 and 10 log CFU/kg BW of microencapsulated LAB12 in pellet form. No mortality or treatment-related findings were observed in terms of clinical body weight, water intake, or food consumption. No treatment-related adverse effects were observed in blood and tissue samples. The no-observed-adverse-effect-level (NOAEL) for microencapsulated LAB12 was 2.5 × 1010 CFU/kg BW for both genders. These results imply that LAB12 are likely non-pathogenic and non-toxic.
    Matched MeSH terms: Temperature
  6. Inhibitory effect of mixture herbs/spices on formation of heterocyclic amines and mutagenic activity of grilled beef
    Sepahpour S, Selamat J, Khatib A, Manap MYA, Abdull Razis AF, Hajeb P
    Food Addit Contam Part A Chem Anal Control Expo Risk Assess, 2018 Aug 23.
    PMID: 29913103 DOI: 10.1080/19440049.2018.1488085
    Natural antioxidants in spices and herbs have attracted considerable attention as potential inhibitors against the formation of mutagenic heterocyclic amines (HCAs) in heat-processed meat. In this study, the inhibitory activity of four spices/herbs and their mixtures on HCAs formation in grilled beef were examined. A simplex centroid mixture design with four components comprising turmeric, curry leaf, torch ginger and lemon grass in 19 different proportions were applied on beef samples before grilling at 240 ºC for 10 min. The HCAs were extracted from the samples using solid phase extraction (SPE) method and analysed using Liquid chromatography mass spectrometry LC-MS/MS. All spices/herbs in single or mixture forms were found to reduce total HCA concentrations in marinated grilled beef ranging from 21.2% for beef marinated with curry leaf to 94.7% for the combination of turmeric and lemon grass (50:50 w/w). At the optimum marinade formula (turmeric: lemon grass 52.4%: 47.6%), concentration of 2-amino-3-methylimidazo[4,5-f]quinolone (IQ), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), Harman, Norharman and AαC were 2.2, 1.4, 0.5, 2.8 and 1.2 ng/g, respectively. The results of the mutagenic activity demonstrated that this optimised marinade formula significantly (p 
    Matched MeSH terms: Hot Temperature
  7. Fulltext The association between climatic factors and dengue fever: a study in Subang Jaya and Sepang, Selangor
    Nik Syaza Lina Nik Ruzman, Haliza Abdul Rahman
    Malaysian Journal of Public Health Medicine, 2017;17(101):0-0.
    MyJurnal
    Dengue fever is one of the most dangerous vector-borne diseases. According to the World Health Organization (WHO), dengue fever is a mosquito-borne infection caused by virus serotype DEN-1, DEN-2, DEN-3 and DEN-4. In Malaysia, dengue fever cases are on the rise from 6,000 cases in 1995 to over 40,000 in 2010, and this number is still rising. In 2014, the increase of dengue fever cases was alarming. It was reported that up to the end of the year 2014, there were 108,698 notified cases, indicating an increment of 151% compared to the same period of time in 2013 with only 43,346 reported cases. Selangor was the highest contributor of dengue fever cases in 2014. The objective of this paper is to study the relationship between climatic factors namely temperature, rainfall and humidity to the prevalence of dengue fever in Subang Jaya and Sepang district, Selangor. Data on monthly average temperature, precipitation, relative humidity and dengue fever cases for each month in 2014 and 2013 were collected. Data collection was dealt with a few institutions such as Malaysian Meteorological Department, Subang Jaya and Sepang Municipal Council and health district offices. Data were analysed using SPSS (Statistical Package for the Social Sciences) Version 20. General linear model analysis was used to investigate the relationship between the climatic variables and dengue prevalence. Results and Discussion: Based on the general linear model, rainfall and humidity were found to have significant relationships to monthly dengue fever cases (p=
    Matched MeSH terms: Temperature
  8. Fulltext Conductivity and FTIR studies on PEO-NaCF3SO3 solid polymer electrolyte films
    Mohd Noor Zairi Mohd Sapri, Azizah Hanom Ahmad
    Science Letters, 2016;10(1):11-13.
    MyJurnal
    Solid polymer electrolytes electrolytes based Poly
    (ethylene oxide) (PEO) complexed with sodium
    trifluoromethanesulfonate (NaCF3SO3
    ) salt were prepared by
    using solution cast technique. Ion-polymer ionic conductivity
    and interaction studies have been reported by Electrical
    Impedance spectroscopy (EIS) and Fourier transform infrared
    spectroscopy (FTIR). FTIR studies suggested that there are
    stronger interaction between Na+
    ions and the polymer than
    interaction of anions cations of the salt. The temperature
    dependance electrical conductivity of polymer electrolytes films
    follow Arrhenius relation and the low activation energy 0.2993
    eV was observed for PEO-18 wt. % NaCF3SO3 below 323 K.
    Matched MeSH terms: Temperature
  9. Fulltext The Binding Efficiency and Interaction of Lactobacillus casei Shirota Toward Aflatoxin B1
    Liew WP, Nurul-Adilah Z, Than LTL, Mohd-Redzwan S
    Front Microbiol, 2018;9:1503.
    PMID: 30042748 DOI: 10.3389/fmicb.2018.01503
    The use of probiotic as dietary approach to prevent exposure to food contaminant, aflatoxin B1 (AFB1) has greatly increased. Several studies found that AFB1 binding to the bacterial cell wall is strain-specific. Moreover, the interaction between AFB1 and bacterial cell wall is not well-understood, thus warrants further investigation. This research was conducted to assess the ability of Lactobacillus casei Shirota (Lcs) to bind AFB1 at different concentrations and to determine AFB1 binding efficiency of different Lcs cell components including live cell, heat-treated, and cell wall. In addition, the interaction between AFB1 and Lcs was also evaluated via scanning electron microscopy (SEM) and through an animal study. The binding of AFB1 by all Lcs cell components depends on the concentration of available AFB1. Among all Lcs cell components, the live Lcs cells exhibited the highest binding efficiency (98%) toward AFB1. Besides, the SEM micrographs showed that AFB1 induced structural changes on the bacterial cell surface and morphology including rough and irregular surface along with a curve rod-shaped. In vivo experiment revealed that Lcs is capable to neutralize the toxicity of AFB1 on body weight and intestine through the binding process. The animal's growth was stunted due to AFB1 exposure, however, such effect was significantly (p < 0.05) alleviated by Lcs. This phenomenon can be explained by a significant (p < 0.05) decreased level of blood serum AFB1 by Lcs (49.6 ± 8.05 ng/mL) compared to AFB1-exposed rats without treatment (88.12 ± 10.65 ng/mL). Taken together, this study highlights the potential use of Lcs as a preventive agent against aflatoxicosis via its strong binding capability.
    Matched MeSH terms: Hot Temperature
  10. Fulltext Review of fruit rot diseases of important tropical and some temperate fruit crops
    Nur Baiti Abd Murad, Nur Ain Izzati Mohd Zainudin
    The Pertanika Journal of Scholarly Research Reviews, 2017;3(1):138-156.
    MyJurnal
    Fruit rot is a common disease that affects the quality and quantity of the produced fruits. It may happened during pre-harvest stage and usually the condition of the fruits will become worse at postharvest stage if there are no any precautions taken during the picking, storing, packaging and transporting processes. The disease is mainly caused by the infection of fungi supported by a conducive condition like susceptible hosts, relative humidity and unsuitable temperature, besides other microorganisms such as bacteria, viruses and nematodes. The infection may arise from soilborne, waterborne, windborne and insects bite transmission. Fruit rot diseases have been reported to cause by many fungal species such as Fusarium species, Alternaria species, Lasiodiplodia species, Aspergillus species, Penicillium species, Colletotrichum species and Botrytis species. This review will provide sufficient information about rot diseases on fruit, fungal species that cause the diseases, effective control methods and managements as well as economic losses and health issues related to the diseases.
    Matched MeSH terms: Temperature
  11. Fulltext Evaluation of disease resistance and tolerance to elevated temperature stress of the selected tissue-cultured Kappaphycus alvarezii Doty 1985 under optimized laboratory conditions
    Azizi A, Mohd Hanafi N, Basiran MN, Teo CH
    3 Biotech, 2018 Aug;8(8):321.
    PMID: 30034985 DOI: 10.1007/s13205-018-1354-4
    Information on the abiotic stress tolerance and ice-ice disease resistance properties of tissue-cultured Kappaphycus alvarezii is scarce and can pose a big hurdle to a wider use of tissue-cultured seaweed in the industry. Here, we reported on a study of seaweed-associated bacteria diversity in farmed and tissue-cultured K. alvarezii, and ice-ice disease resistance and elevated growth temperature tolerance of tissue-cultured K. alvarezii in laboratory conditions. A total of 40 endophytic seaweed-associated bacteria strains were isolated from 4 types of K. alvarezii samples based on their colony morphologies, Gram staining properties and 16S rRNA gene sequences. Bacteria strains isolated were found to belong to Alteromonas sp., Aestuariibacter sp., Idiomarina sp., Jejuia sp., Halomonas sp., Primorskyibacter sp., Pseudoalteromonas sp., Ruegeria sp., Terasakiella sp., Thalassospira sp. and Vibrio sp. Vibrio alginolyticus strain ABI-TU15 isolated in this study showed agar-degrading property when analyzed using agar depression assay. Disease resistance assay was performed by infecting healthy K. alvarezii with 105 cells/mL Vibrio sp. ABI-TU15. Severe ice-ice disease symptoms were detected in farmed seaweeds compared to the tissue-cultured K. alvarezii. Besides disease resistance, tissue-cultured K. alvarezii showed better tolerance to the elevated growth temperatures of 30 and 35 °C. In conclusion, our overall data suggests that tissue-cultured K. alvarezii exhibited better growth performance than farmed seaweeds when exposed to elevated growth temperature and ice-ice disease-causing agent.
    Matched MeSH terms: Temperature
  12. Fulltext Biochemical changes of fresh and preserved freshwater prawns (Macrobrachium rosenbergii) during storage
    Abu Bakar, F., Salleh, A.B., Razak, C.N.A., Basri, M., Ching, M.K., Son, R.
    International Food Research Journal, 2008;15(2):181-191.
    MyJurnal
    Biochemical analysis was carried out for pH profiles, freshness in terms of K-values, amino acids profiles, total volatile bases (TVB), total volatile acids (TVA) and biogenic amines for fresh and preserved Macrobrachium rosenbergii. Results showed that pH profiles of Macrobrachium rosenbergii explain the inability of this parameter to be used to evaluate the quality of Macrobrachium rosenbergii. Thus changes in pH profiles of Macrobrachium rosenbergii should be combined with indicators such as total volatile acids and total volatile bases. Total volatile acids of the shrimps increased steadily in small amounts throughout the storage period. A rapid increase in TVB at 100C was detected due to the increase in total aerobic bacteria at elevated temperatures. The microbial activities caused the decrease in the amino acids arginine, lysine and histidine which correlated well with the increase in the corresponding biogenic amines such as putrescine, cadaverine and histamine respectively. Preservatives used in this study controlled the production of these biogenic amines without significantly altering the pH of preserved shrimp.
    Matched MeSH terms: Temperature
  13. Fulltext Production of spray-dried Sarawak pineapple (Ananas comosus) powder from enzyme liquefied puree
    Pui, L. P., Ng. J. M. L., Wong, C. W.
    International Food Research Journal, 2015;22(4):1631-1636.
    MyJurnal
    Spray drying is used widely for converting liquid food products into powder form as the dried powder is known to have a longer shelf life at ambient temperature, convenience to use and low transportation expenditure. In this study, the Sarawak pineapple puree was spray-dried and the characterization of the resulting powder was performed. The process of enzyme liquefaction was optimized with Pectinex® Ultra SP-L and Celluclast® 1.5 L (single and combined treatment) at different concentrations (0–2.5 %) and incubation time (0-2.5 hours). The combined treatment with both enzymes (1.5% v/w Pectinex® Ultra SP-L + 0.5% v/w Celluclast® 1.5 L, 1.5 hour) was found to be the best parameter, which produced purees with the lowest viscosity of 67.98 ± 4.27 cp. Optimization of spray drying process was carried out using different inlet temperatures (150-180°C) and maltodextrin concentrations (15-30 % w/w). Results indicated that the spraydried powder produced at 160°C with 15% w/w of maltodextrin has the highest yield (31.63 %). The spray-dried powder was further characterized for the moisture content (6.00 ± 0.63%), water activity (0.36 ± 0.01 Aw), hygroscopicity (17.35 ± 0.64%), bulk density (0.46 ± 0.04 g/ cm3 ) and solubility (87.33 ± 2.08 seconds). The fruit powder of this study can be incorporated into different fruit added –value products, such as fruit juice, yogurt, jelly and other beverages.
    Matched MeSH terms: Temperature
  14. Fulltext Dynamics of the Water Circulations in the Southern South China Sea and Its Seasonal Transports
    Daryabor F, Ooi SH, Samah AA, Akbari A
    PLoS One, 2016;11(7):e0158415.
    PMID: 27410682 DOI: 10.1371/journal.pone.0158415
    A three-dimensional Regional Ocean Modeling System is used to study the seasonal water circulations and transports of the Southern South China Sea. The simulated seasonal water circulations and estimated transports show consistency with observations, e.g., satellite altimeter data set and re-analysis data of the Simple Ocean Data Assimilation. It is found that the seasonal water circulations are mainly driven by the monsoonal wind stress and influenced by the water outflow/inflow and associated currents of the entire South China Sea. The intrusion of the strong current along the East Coast of Peninsular Malaysia and the eddies at different depths in all seasons are due to the conservation of the potential vorticity as the depth increases. Results show that the water circulation patterns in the northern part of the East Coast of Peninsular Malaysia are generally dominated by the geostrophic currents while those in the southern areas are due solely to the wind stress because of negligible Coriolis force there. This study clearly shows that individual surface freshwater flux (evaporation minus precipitation) controls the sea salinity balance in the Southern South China Sea thermohaline circulations. Analysis of climatological data from a high resolution Regional Ocean Modeling System reveals that the complex bathymetry is important not only for water exchange through the Southern South China Sea but also in regulating various transports across the main passages in the Southern South China Sea, namely the Sunda Shelf and the Strait of Malacca. Apart from the above, in comparision with the dynamics of the Sunda Shelf, the Strait of Malacca reflects an equally significant role in the annual transports into the Andaman Sea.
    Matched MeSH terms: Temperature
  15. Feed-based vaccination regime against streptococcosis in red tilapia, Oreochromis niloticus x Oreochromis mossambicus
    Ismail MS, Siti-Zahrah A, Syafiq MR, Amal MN, Firdaus-Nawi M, Zamri-Saad M
    BMC Vet Res, 2016;12(1):194.
    PMID: 27608936 DOI: 10.1186/s12917-016-0834-1
    Streptococcosis is an important disease of tilapia throughout the world. In Malaysia, streptococcosis outbreak was commonly reported during the 3-month period of high water temperature between April and July. This study describes the duration of protection following single and double booster dose regimes against streptococcosis in tilapia using a feed-based vaccine containing formalin-killed Streptococcus agalactiae. A total of 510 tilapias of 120 ± 10 g were selected and divided into 3 groups. Fish of Group 1 were vaccinated at weeks 0 and 2 (single booster group) while fish of Group 2 were vaccinated at weeks 0, 2 and 6 (double booster group) with a feed-based vaccine against streptococcosis. Fish of Group 3 was not vaccinated. Serum samples were collected weekly to determine the antibody level while samples of eye, brain and kidney were collected for bacterial isolation. At week 10, all fish were challenged with live S. agalactiae and the survival rate was determined.
    Matched MeSH terms: Temperature
  16. Biodiesel Production from Citrillus colocynthis Oil Using Enzymatic Based Catalytic Reaction and Characterization Studies
    Nehdi IA, Sbihi HM, Blidi LE, Rashid U, Tan CP, Al-Resayes SI
    Protein Pept Lett, 2018;25(2):164-170.
    PMID: 28240158 DOI: 10.2174/0929866524666170223150839
    BACKGROUND: Biodiesel is a green fuel consisting of long chain fatty acid monoalkyl esters, which can be blended with diesel or used alone which is usually produced from vegetable oils/fats by either lipasecatalyzed transesterification. In this investigation, an enzyme (Novozym 435) catalyzed process was optimized to prepare methyl esters from crude Citrullus colocynthis oil (CCO) by transesterification of CCO with methanol. However, as per our knowledge, lipase-catalyzed transesterification have not been used for biodiesel production from Citrullus colocynthis.

    OBJECTIVE: The purpose of this work was to transesterify the CCO in the presence of Candida antarctica lipase as catalyst and methanol. Additionally, the physicochemical parameters/fuel properties of the Citrullus colocynthis methyl ester (CCME) were assessed and compared.

    METHODS: Lipase-catalyzed reactions were carried out in three necked flask (50 mL) attached with reflux condenser and thermometer, immersed in oil bath at constant stirring speed (400 rpm). The reaction mixture was consisted of CCO and varying the calculated amount of methanol, tert-butyl alcohol, and Novozym 435. The experimental parameters reaction time, methanol/oil molar ratio, reaction temperature, tert-butanol content, Novozym 435 content and water content were optimized for the transesterification reaction. The CCME yield was measured using gas chromatograph. The fuel properties of the produced CCME were determined as per American Society for Testing and Materials (ASTM) and European (EN) biodiesel standard methods.

    RESULTS: In this study, an enzymatic catalyst was employed to synthesize the CCME from CCO via transesterification. Several variables affecting the CCME yield were optimized as lipase quantity (4%), water content (0.5%), methanol/oil molar ratio (5:1), reaction temperature (43 °C), reaction medium composition (80% tertbutanol/ oil), and reaction time (3.7 h). A CCME yield of 97.8% was achieved using enzyme catalyzed transesterification of CCO under optimal conditions. The significant biodiesel fuel properties of CCME, i.e. cloud point (0.70 °C); cetane number (49.07); kinematic viscosity (2.27 mm2/s); flash point (143 °C); sulfur content (2 ppm) density (880 kg/m3) and acid value (0.076 mg KOH/g) were appraised. CCME also exhibited long-term storage stability (4.80 h) and all the biodiesel fuel properties were within the range of standards (ASTM D6751 and EN 14214).

    CONCLUSION: The lipase-catalyzed transesterification produced better conversion than the base-catalyzed reaction. The fuel properties of CCME were within the limits of the ASTM D6751 and EN14214 standards. Furthermore, CCME showed good oxidative stability and a long shelf life due its high natural antioxidant content. CCME showed better fuel properties and long-term storage stability due to which it can be used as a potential alternative fuel.

    Matched MeSH terms: Temperature
  17. Fulltext Quantification of anti-fertility compound-diosgenin concentration in the fenugreek seeds aqueous extract (FSA)
    Ahmed Kaid, N. A., Norbaiyah, M. B., Imad, M. A., Norazian, M. H.
    International Medical Journal Malaysia, 2016;15(1):75-80.
    MyJurnal
    Introduction: This study aims to build a standardization method for preparation of effective powder from
    FSA and to quantify diosgenin in FSA. Methodology: One kg of FS were used in this study. Setting: BMS, KOM
    and KOP, IIUM Kuantan campus. FS were washed with distilled water to exclude any foreign matter, and
    were then air dried. FS-powder were put in distilled water in a ratio of 1 g of powder in 20 ml of distilled
    water and were shaken at room temperature for 24 hours. Ten mg of hydrolyzed extract sample was diluted
    in 10 ml volumetric flask with methanol for 15 minutes. Chromatographic estimation was performed using
    an equilibrated reverse phase Eclipse XDB-C18 column (particle size 5 µg, 4.6 mm x 150 mm). Results: One
    gram of FSA extract was hydrolyzed to produce sapogenins and 46.6% was recovered. A calibration curve
    that was constructed based on five dilutions of diosgenin standard at concentrations of 2, 5, 10, 20, 30 and
    50 ppm produced a linear graft (r = 0.999). The concentration of diosgenin in FSA extract as calculated using
    the regression analysis was found to be 29.66 µg/ml, 13.81 % w/w on dried weight basis. Conclusion:
    Preparation and standardization of effective powder from FSA are the corner stone of many scientific
    researches in IIUM and Malaysia. Diosgenin is available in the FSA in adequate concentration. The adequate
    amount of diosgenin in the FSA will guide us to do further study in the way of preparation of a natural
    product that can be used in the field of reversible anti-fertility therapy.
    Matched MeSH terms: Temperature
  18. Arginine Complexes with Simvastatin: Apparent Solubility, In Vitro Dissolution and Solid State Characterization
    Affandi MMRMM, Tripathy M, Majeed ABA
    Curr Drug Deliv, 2018;15(1):77-86.
    PMID: 28322162 DOI: 10.2174/1567201814666170320144259
    BACKGROUND: Categorized as a Biopharmaceutics Classification System (BCS) Class II drugs, statin exhibit low aqueous solubility and bioavailability thus presenting an obstacle and great challenge to formulation researchers. This paper describes a de novo approach to enhance the aqueous solubility of one of the most commonly prescribed statins i.e., simvastatin (SMV) by forming a complex (SMV-ARG) with cosolute arginine (ARG).

    METHODS: The complex has been characterized for its apparent solubility and in vitro dissolution. The solid state characterization has been carried out using Fourier Transform Infra-Red (FTIR) Spectroscopy, Elemental Analysis, X-Ray Powder Diffraction (XRD), Differential Scanning Calorimetry (DSC) analysis, Thermal Gravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM).

    RESULTS: Simvastatin-Arginine (SMV-ARG) complex exhibited massive solubility enhancement by 12,000 fold and significant improvement in both acidic and alkaline dissolution media. A conversion of coherent crystalline to non-coherent pattern, and certain extent of amorphization in SMV-ARG complex, fully justifies the enhanced solubility, and hence the dissolution profile.

    CONCLUSION: The present study provides a significant evidence that ARG molecules are capable to form a complex with small molecules and increase their aqueous solubility which prove to be beneficial in drug formulation and development.

    Matched MeSH terms: Temperature
  19. Effects of different types of biochar on methane and ammonia mitigation during layer manure composting
    Chen W, Liao X, Wu Y, Liang JB, Mi J, Huang J, et al.
    Waste Manag, 2017 Mar;61:506-515.
    PMID: 28117129 DOI: 10.1016/j.wasman.2017.01.014
    Biochar, because of its unique physiochemical properties and sorption capacity, may be an ideal amendment in reducing gaseous emissions during composting process but there has been little information on the potential effects of different types of biochar on undesired gaseous emissions. The objective of this study was to examine the ability and mechanism of different types of biochar, as co-substrate, in mitigating gaseous emission from composting of layer hen manure. The study was conducted in small-scale laboratory composters with the addition of 10% of one of the following biochars: cornstalk biochar, bamboo biochar, woody biochar, layer manure biochar and coir biochar. The results showed that the cumulative NH3 production was significantly reduced by 24.8±2.9, 9.2±1.3, 20.1±2.6, 14.2±1.6, 11.8±1.7% (corrected for initial total N) in the cornstalk biochar, bamboo biochar, woody biochar, layer manure biochar and coir biochar treatments, respectively, compared to the control. Total CH4 emissions was significantly reduced by 26.1±2.3, 15.5±2.1, 22.4±3.1, 17.1±2.1% (corrected for the initial total carbon) for cornstalk biochar, bamboo biochar, woody biochar and coir biochar treatments than the control. Moreover, addition of cornstalk biochar increased the temperature and NO3(-)-N concentration and decreased the pH, NH4(+)-N and organic matter content throughout the composting process. The results suggested that total volatilization of NH3 and CH4 in cornstalk biochar treatment was lower than the other treatments; which could be due to (i) decrease of pH and higher nitrification, (ii) high sorption capacity for gases and their precursors, such as ammonium nitrogen from composting mixtures, because of the higher surface area, pore volumes, total acidic functional groups and CEC of cornstalk biochar.
    Matched MeSH terms: Temperature
  20. Frequency-controlled wireless shape memory polymer microactuator for drug delivery application
    Zainal MA, Ahmad A, Mohamed Ali MS
    Biomed Microdevices, 2017 Mar;19(1):8.
    PMID: 28124762 DOI: 10.1007/s10544-017-0148-5
    This paper reports the wireless Shape-Memory-Polymer actuator operated by external radio frequency magnetic fields and its application in a drug delivery device. The actuator is driven by a frequency-sensitive wireless resonant heater which is bonded directly to the Shape-Memory-Polymer and is activated only when the field frequency is tuned to the resonant frequency of heater. The heater is fabricated using a double-sided Cu-clad Polyimide with much simpler fabrication steps compared to previously reported methods. The actuation range of 140 μm as the tip opening distance is achieved at device temperature 44 °C in 30 s using 0.05 W RF power. A repeatability test shows that the actuator's average maximum displacement is 110 μm and standard deviation of 12 μm. An experiment is conducted to demonstrate drug release with 5 μL of an acidic solution loaded in the reservoir and the device is immersed in DI water. The actuator is successfully operated in water through wireless activation. The acidic solution is released and diffused in water with an average release rate of 0.172 μL/min.
    Matched MeSH terms: Temperature
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