In this paper, novel zwitterionic graphene oxide (GO) nanohybrid was synthesized using monomers [2-(Methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA) and N,N'-methylenebis(acrylamide) (MBAAm) (GO@poly(SBMA-co-MBAAm), and incorporated into polysulfone (PSF) hollow fiber membrane for the effectual rejection of dye from the wastewater. The synthesized nanohybrid was characterized using FT-IR, PXRD, TGA, EDX, TEM and zeta potential analysis. The occurrence of nanohybrid on the membrane matrix and the elemental composition were analyzed by XPS. The as-prepared tight ultrafiltration hollow fiber membrane exhibited high rejection of reactive black 5 (RB-5, 99%) and reactive orange 16 (RO-16, 74%) at a dye concentration of 10 ppm and pure water flux (PWF) of 49.6 L/m2h. Fabricated nanocomposite membranes were also studied for their efficacy in the removal of both monovalent (NaCl) and divalent salts (Na2SO4). The results revealed that the membrane possesses complete permeation to NaCl with less rejection of Na2SO4 (<5%). In addition, the nanocomposite membrane revealed outstanding antifouling performance with the flux recovery ratio (FRR) of 73% towards bovine serum albumin (BSA). Therefore, the in-house prepared novel nanocomposite membrane is a good candidate for the effective decolorization of wastewater containing dye.
This review article highlights the thermal behaviors of selected starches that were studied using differential scanning calorimetery (DSC) with data shown in various research publications. The starches of sago, potato, sweet potato, cassava, yam, and corn are included in this overview. Our examinations indicate that thermal properties are highly affected by the type of starch, its amylose/amylopectin content, and the presence of other food ingredients such as sugar, sodium chloride, water, milk, hydrocolloids, and meat. When the heating temperatures of the starches were increased, the DSC measurements also showed an increase in the temperatures of the gelatinization (onset [To ], peak [Tp ], and conclusion [Tc ]). This may be attributed to the differences in the degree of crystallinity of the starch, which provides structural stability and makes the granule more resistant to gelatinization.
Introduction: The compatibility of denture cleanser is crucial in the prevention of failure of adhesion between silicone soft liner and acrylic denture base, thus ensuring the durability of the prosthesis. This scanning electron microscope (SEM) study was to determine the mode of failure and measured the gap formation between silicone soft liners and Polymethylmethacrylate (PMMA) denture base after immersion in denture cleansers. Methods: A total of 135 specimens of PMMA denture base lined with three different silicone soft liners (GC Reline Soft, Mollosil and Tokuyama Sofreliner Tough) were immersed into denture cleansers (Polident® and Stearadent) daily and stored in distilled water at 37±1°C. Specimens were examined and sectioned at 2.5mm and 5.0mm from the margin after 1 day, 30 days and 90 days before analyzed. Results: No significant difference detected in the mode of failure and gap formation after one-day immersion. Adhesive failure was the commonest failure at the margin after 30 days (71.11%) and after 90 days (95.56%). However, 33.33% of specimens showed mixed failure at 5.0mm sectioned after 90 days. A significant difference of gap formation was demonstrated from Mollosil in Steradent at the margin and at 2.5 mm sectioned after 30 days and after 90 days (p
Introduction: High sodium consumption over an extended period of time has been associated with hypertension, stroke, cardiovascular disease, renal damage, and other adverse health effects. This study aimed to determine urinary sodium excretion and consequently estimate dietary sodium consumption among normotensive health staff in Malaysia. Methods: A cross-sectional study was conducted to acquire data on sodium excretion among normotensive Ministry of Health staff aged 20 - 56 years (mean age 35.08, SD 9.78) in 14 states and a research institute. Respondents were recruited using quota sampling. Data collection was conducted from December 2011 to February 2012. A single urine sample was collected over 24 hours for sodium concentrations and calculated as 95.0% of total daily sodium intake. Results: Among the 471 enrolled respondents, 445 (94.0%) provided complete information on socio-demography and urine samples. Mean urine sodium excretion was 142.0 mmol/day (SD 71.7), which is equivalent to 3429 mg sodium/day or 8.7 gm of salt intake (1.75 teaspoon, which exceeds the Malaysian recommendation of 2000 mg sodium/day by 1.7 times. About 79.0% (n=353) of respondents (88.0% male and 73.0% female) had daily sodium consumption that was above the recommendation. Excretion was significantly higher among males at 161.7 mmol/day (SD 78.1) (3726 mg sodium/day) than females, 125.3 mmolfday (SD 61.1) (2875 mg/day). There was a positive, low correlation between BMl and sodium intake (r=0.216, p
Citrus canker caused by Xanthomonas citri subsp. citri is a disease affecting the yield and fruit quality of lime (Citrus aurantiifolia). This research investigated endophytic bacteria obtained from six healthy Citrus spp. to inhibit the pathogen and to control citrus canker on lime plants. Numbers of the endophytic bacteria isolated from C. aurantifolia, C. hystrix, C. maxima, C. nobilis, C. reticulata and C. sinensis were 28, 25, 29, 42, 12 and 34 isolates, respectively. The selected endophytic bacteria that were effective against X. citri subsp. citri were Bacillus amyloliquefaciens LE109, B. subtilis LE24 and B. tequilensis PO80. The optimum culture medium for an antagonistic effect on the pathogen in B. amyloliquefaciens LE109 and B. tequilensis PO80 was yeast extract peptone dextrose broth, and in B. subtilis LE24 was modified soluble starch broth. To control citrus canker in lime, young expanded leaves of lime plants were aseptically punctured and inoculated with 30 μl of bacterial suspension of the pathogen (108 CFU/ml in 0.85% NaCl) per punctured location. After the pathogenic inoculation for 24 h, the leaves were then inoculated with 30 μl of the selected endophytic bacteria (108 CFU/ml in 0.85% NaCl), and treated with 30 μl of the culture media containing bioactive compounds produced by the selected endophytic bacteria. The leaves inoculated with cell suspensions of B. amyloliquefaciens LE109 or B. subtilis LE24 could completely control citrus canker. However, the leaves inoculated with B. tequilensis PO80 displayed 10% disease incidence. Additionally, the leaves treated with the crude bioactive compounds of B. amyloliquefaciens LE109 or B. subtilis LE24 could completely control citrus canker. Notably, the leaves treated with the crude bioactive compounds of B. tequilensis PO80 displayed 5% disease incidence. The results of this study showed that the Bacillus strains play important roles in the biocontrol of citrus canker in lime.
Recent studies by the United Nations University - Institute of Advanced Studies (UNU-IAS) demonstrate that bioprospecting is taking place in Antarctica and the Southern Ocean and that related commercial applications were being marketed. The bioprospectors’ interest in Antarctica stems from two reasons. First, the lack of knowledge surrounding Antarctic biota provides opportunities to discover novel organisms of potential use to biotechnology. Second, Antarctica’s environmental extremes, such as cold temperatures, extreme aridity and salinity present conditions in which biota have evolved unique characteristics for survival (UNU-IAS 2003). Thus bioprospecting opportunities include, inter alia, the discovery of novel bioactives in species found in cold and dry lithic habitat, novel pigments found in hyper-saline lakes and antifreezes in sea-lakes (Cheng & Cheng 1999).
Marination directly affects the texture and flavor of meat and is important for product yield. This research investigated the effects of various marinating solutions on the physicochemical, microstructural and sensory properties of golek chicken, a popular dish in Malaysia, Indonesia and southern Thailand. Non-marinated meat (Tr1-control) was compared with five marinating treatments: distilled water (Tr2); sodium chloride (Tr3); a mixture of sodium chloride and sodium tripolyphosphate (STPP) (Tr4); a mixture of sodium chloride, STPP and citric acid (Tr5); and a mixture of sodium chloride, STPP and sodium bicarbonate (Tr6). Marinating meat in Tr3–Tr6 resulted in higher water-holding capacity and cooking yield, as well as lower shear force value and cooking loss, when compared to Tr1 and Tr2 (p
The objective of this study was to determine the Immunoglobulin E-binding proteins (IgE) and major allergens of Scomberomorus commerson Lacepede (Narrow-barred Spanish mackerel). Allergen extracts were obtained from uncooked and cooked fish by homogenization in phosphate-buffered saline followed by continuous extraction at 4oC or on ice. Protein profiles and IgEbinding patterns were then detected by means of sodium dodecyl polyacrylamide gel electrophoresis (SDS PAGE) and immunoblotting using sera from patients sensitized to the fish. SDS-PAGE of the uncooked fish extracts revealed 26 protein bands in the range of about 11 to >175 kD, while the cooked extracts produced fewer protein bands. Immunoblotting demonstrated 17 IgE-binding bands, ranging in molecular weight from 11 to 151 kD. Two components with molecular weight of about ~50 and 42 kD showed the highest frequency of IgE-binding (62.2 and 51.4% respectively) and were identified as the major allergens of this fish allergy. Other IgE-binding proteins including a protein at ~12 kD which was equivalent in size to parvalbumin were identified as the minor allergens.
This study aimed to detect the presence of enterococci in the root canals of untreated and treated teeth with periapical disease and to compare this to their presence in the saliva and in the immediate surgical environment during root canal treatment. Using an aseptic technique, 33 samples were obtained from 27 untreated and 6 previously treated teeth associated with apical periodontitis. Reduced Transport Fluid (RTF) was used as transport medium. Saliva samples and areas in the surgical environment were also sampled. These were performed prior to chemo-mechanical debrjdement and obturation for every case. The saliva was diluted to 10- J and was plated on Bile Aesculin Azide (BEA) agar whereas the rest of the samples were plated on Bile Aesculin (BE) agar. These plates were then incubated aerobically at 37°C for 48 hours. All the colony types that blackened the agar were sub-cultured to obtain pure isolates and tested on 6.5% sodium chloride (NaCI). Growth on this medium was Gram stained for further confirmation of cell morphology. Gram positive cocci isolated from previous positive test were identified as enterococci. Enterococci were recovered from untreated cases only; from 2 teeth (in 2 patients) prior to chemo-mechanical debridement, from 3 teeth (in 3 patients) prior to obturation and I from saliva sample. A 'total of 5 samples from 5 different patients were positive for enteroco•cci. Sampling in the immediate surgical environment revealed a low occurence in the range of3.0% (1/33) to 15_2% (5/33). In conclusion, the occurence of enterococci in patients and the immediate surgical environment was low number.
The application of magnetized graphene (G) layers synthesized on the carbon nanofibers (CNFs) (m-G/CNF) was investigated as novel adsorbent for the magnetic solid-phase extraction (MSPE) of polycyclic aromatic hydrocarbons (PAHs) in water samples followed by gas chromatography-flame ionization detector (GC-FID). Six important parameters, affecting the extraction efficiency of PAHs, including: amount of adsorbent, adsorption and desorption times, type and volume of the eluent solvent and salt content of the sample were evaluated. The optimum extraction conditions were obtained as: 5min for extraction time, 20mg for sorbent amount, dichloromethane as desorption solvent, 1mL for desorption solvent volume, 5min for desorption time and 15% (w/v) for NaCl concentration. Good performance data were obtained at the optimized conditions. The calibration curves were linear over the concentration ranges from 0.012 to 100ngmL(-1) with correlation coefficients (r) between 0.9950 and 0.9967 for all the analytes. The limits of detection (LODs, S/N=3) of the proposed method for the studied PAHs were 0.004-0.03ngmL(-1). The relative standard deviations (RSDs) for five replicates at two concentration levels (0.1 and 50ngmL(-1)) of PAHs were ranged from 3.4 to 5.7%. Appropriate relative recovery values, in the range of 95.5-99.9%, were also obtained for the real water sample analysis.
The present study aimed to provide an insight of C. jejuni ATCC 33560 phenotype profiles (carbon sources and sensitivity to osmolytes and pH) using Phenotypic MicroArray (PM) system in response to optimal and suboptimal temperature. C. jejuni ATCC 33560 showed utilization carbon sources from amino acids and carboxylates but not from sugars. C. jejuni ATCC 33560 is sensitive to NaCl at 2% and above but showed survival in a wide range of food preservatives (sodium lactate, sodium phosphate, sodium benzoate, ammonium sulphate and sodium nitrate). When incubated at suboptimal temperature, no phenotype loss was observed in carbon source plates. Phenotype loss of C. jejuni ATCC 33560 was observed in sodium chloride (1%), sodium sulphate (2-3%), sodium formate (1%), sodium lactate (7-12%), sodium phosphate pH7 (100mM and 200mM), ammonium sulphate pH8 (50mM), sodium nitrate (60mM, 80mM and 100mM), sodium nitrite (10mM), and growth in pH5. The phenotypic profile from present study will provide a better insight related to survival of C. jejuni ATCC 33560.
The extraction method for the determination of ochratoxin A (OTA) in black pepper was optimized. The influence of three variables, i.e., type of solvent, solvent-volume-to-sample- size ratio (v/w) and amount of sodium chloride (NaCl) (g), on OTA recovery was evaluated. Analysis of variance was used to compare recovery values obtained from different solvents, and response surface methodology (RSM) was used to determine the optimum amount of NaCl and the solvent-volume-to-sample-size ratio. The concentration of OTA was determined by high-performance liquid chromatography with fluorescence detection. The highest recovery (95.2 %) was obtained when methanol/water (80:20, v/v) was used as the solvent. The RSM results showed that the experimental data could be adequately fitted to a second-order polynomial model with multiple regression coefficients (R2) of 0.962. The optimum amount of NaCl was determined to be 3 g, whereas the optimum solvent-volume-to-sample-size ratio (v/w) was found to be 4. The proposed method was applied to 20 samples, and the presence of OTA was found in 8 (40%) samples ranging from 0.11 to 3.16 ng g-1.
This paper reports the nutrition knowledge of Malaysian elderly, as part of a nationwide study to evaluate the status of nutrition knowledge, attitude and practice (KAP) of food and nutrition among various communities in Malaysia. A total of 906 elderly, age ranging between 60 to 96 years old, with mean age 67.4 ± 6.7 years representing all states in Malaysia participated in the study. An interview administered questionnaire was used to assess the nutrition knowledge and to collect demographic data of the elderly. Subjects were in the 60-65 years (51%) and more than 65 years (49%) age category. There were 46% Malays, 32% Chinese, 6% Indians while the remaining 16% comprised of other minority groups in Malaysia such as Iban, Kadazan, Melanau, Orang Asli and others. More than half of the elderly (54%) had no formal education, 36% completed primary schooling and only 9% finished secondary education. Overall 73% elderly were categorized as having poor nutrition knowledge, 18% moderate and only 9% good. The minority groups had the highest percentage of poor nutrition knowledge (91%) while the Chinese had the highest percentage of good nutrition knowledge (11%). More female (78%) than male (67%) had poor nutrition knowledge, in contrast to more male (10%) than female (8%) with good nutrition knowledge. Chi square test showed that there was a significant correlation between educational status and nutrition knowledge. This was reflected in the results which showed that 81% elderly with no formal education were categorized in the poor nutrition knowledge group. Majority of the elderly did not know about foods to be consumed most (88%), or to be eaten least (87%). Only a quarter to a third of the elderly responded correctly to questions on nutrient function and content. The question on foods with high salt was well responded by the elderly (65%). It is quite discouraging to show that a majority of Malaysian elderly had poor nutrition knowledge. This study indicated that appropriate nutrition education interventions need to be implemented to improve the shortcomings of nutrition knowledge among the Malaysian elderly.
A descriptive study was conducted to evaluate the prevalence of Blastocystis hominis in children aged between 1-12 years old from randomly selected villages in Alor Gajah district Melaka. The sampling was carried out from 1st to 7th of July of 2006. A total of 48 faecal samples were obtained from the children in those studied villages. The faecal specimens were examined by direct saline wet moun, formalin ethyl acetate concentration and trichrome staining method. It was found that 45.8% (22 out of 48) of the examined children were infected with Blastocystis hominis . Based on the results, the cumulative prevalence of three methods used showed that Blastocystis hominis infection in female children higher compared to male children. Whilst the schooling children aged of 6 to 12 years had a higher prevalence than pre school children at the age of 1-5 years. In term of diagnosis, formalin ethyl acetate concentration method showed prevalence of detection at 60.9%. It was followed by direct saline wet mount (43.5%) and trichrome staining at 34.8%.
Silver catfish (Pangasius sutchi) skin gelatin was extracted to determine the effects of extraction time on the functional properties of the gelatin in terms of solubility, protein solubility as a function of pH and sodium chloride concentration, emulsifying capacity and stability, water holding capacity, fat binding capacities and foaming properties. Silver catfish skins were washed in sodium chloride (NaCl) solution prior to pre-treatment in sodium hydroxide (NaOH) and acetic acid solution. Gelatin was extracted at 50ºC for 6, 8, 10 and 12 hours extraction time followed by freeze drying. The extraction of silver catfish skin gelatin at 50 ºC for 12 hours was more effective than extraction at 6, 8 and 10 hours where the gelatin was characterized by higher emulsifying capacity (52.63%), emulsifying stability (47.83%), water holding capacity (31.78 mL/g), fat binding capacities (54.76%), foaming capacity (41.47 mL) and foaming stability (56.42%) than gelatins extracted at other extraction time. The longer the extraction time, the better the functional properties of the gelatin. Based on its good functional properties, silver catfish skin gelatin may be useful in various food applications such as soups, sauces and gravies.
Polyaniline (PANI) and polyaniline composites with aluminium oxide (Al2O3) were prepared using the in situ polymerization method. The composites were then blended with acrylic paint and applied to carbon steel panels. The coated steel panels were evaluated for corrosion using the immersion test technique. The results revealed that the steel panels coated with polyaniline composites and with Al2O3 containing coatings had small corrosion as compared to the bare sample and the samples coated with polyaniline and paint alone. The samples were characterized by Fourier transform infrared (FTIR) and X-ray diffraction(XRD). In addition, the morphology of the finished samples was observed using the scanning electron microscopy (SEM). This novel composite was used as a paint pigment for enhancing the barrier properties and the paint protectable against aggressive ions. Meanwhile, corrosion was evaluated through visual monitoring using a digital camera after 60 days of fully immersion test in 5% NaCl. The weight loss method was also used to evaluate corrosion.
Austempering is one of the trendiest heat treatment processes to promote the strength and toughness of ductile iron. However, such practice is complex because it involves using aqueous solutions as quenchant (salt bath solution). This study was conducted to analyse the heat treatment of the combination processes of annealing-austenitising and evaluate the correlation between microstructure constituent and hardness of the ductile iron. Ductile iron samples in form of double cylinder was produced by conventional CO2 sand casting method. The new heat treatment process was started by annealed at 873 K for 1.8 ks before being oil quenched. Subsequently, the samples were austenitised at austenitising temperatures 1123 K, 1173 K and 1223 K for 3.6 ks respectively before being immediately oil quenched to room temperature. A series of microstructure analysis tests, including optical microscopy and X-ray diffraction (XRD) was applied. Vickers microhardness tester was used to measure the hardness for each microstructure constituent. The results showed that ductile iron matrix transforms to martensitic during heat treatment of annealing-austenitising combination processes, which in turn contributes to increasing microhardness of martensite and the bulk hardness of ductile iron.
A new cloud point methodology was successfully used for the extraction of carcinogenic pesticides in milk samples as a prior step to their determination by spectrophotometry. In this work, non-ionic silicone surfactant, also known as 3-(3-hydroxypropyl-heptatrimethylxyloxane), was chosen as a green extraction solvent because of its structure and properties. The effect of different parameters, such as the type of surfactant, concentration and volume of surfactant, pH, salt, temperature, incubation time and water content on the cloud point extraction of carcinogenic pesticides such as atrazine and propazine, was studied in detail and a set of optimum conditions was established. A good correlation coefficient (R2 ) in the range of 0.991-0.997 for all calibration curves was obtained. The limit of detection was 1.06 µg l-1 (atrazine) and 1.22 µg l-1 (propazine), and the limit of quantitation was 3.54 µg l-1 (atrazine) and 4.07 µg l-1 (propazine). Satisfactory recoveries in the range of 81-108% were determined in milk samples at 5 and 1000 µg l-1, respectively, with low relative standard deviation, n = 3 of 0.301-7.45% in milk matrices. The proposed method is very convenient, rapid, cost-effective and environmentally friendly for food analysis.
Calixarene derivatives are reported as potential therapeutic agents. Azo derivatives of calixarenes have not been given much consideration to explore their biomedical applications. In the present study, some azo-based derivatives of calix[4]arene were synthesized and characterized and their antibacterial and antiviral potentials were studied. The mono azo products of sulphanilamide, sulfaguanidine and 2-methyl-4-aminobenzoic acid showed good activity against bacterial strains with minimum inhibition concentration values ranging from 0.97 to 62.5 μg/mL. For mono azo products, the diazotized salt was applied as a limiting reagent. The use of calix[4]arene and sodium acetate trihydrate in 1:3 (molar ratio) helped in partial substitution. Molecular docking was performed to see the interaction of the designed compounds with two bacterial and one viral (neuraminidase) receptor. Some of the derivatives showed good interaction with the active site of bacterial and neuraminidase enzymes through hydrogen, hydrophobic and pi-pi interactions, and could inhibit the activity of the selected enzymes.
Microalgae biorefinery is presently receiving a lot of attention as driven by its production of high value-added products. In this study, an oleaginous microalga Aurantiochytrium limacinum SR21 was cultured for docosahexaenoic acid (DHA) production using 20% (w/v) of K2HPO4-waste feedstock to replace 0.005% (w/v) of KH2PO4 in the flask culture. DHA is an essential nutrient for human's brain functionalities. Collectively, the K2HPO4-waste feedstock with working concentration of 0.005% (w/v) in the cultivation prompted a higher lipid content (8.29%) and DHA production (128.81 mg.L-1). Moreover, natural plant pigment products containing stabilised betacyanins were utilised as natural red colourants for hard candy production. This study develops microalgal cultivation using salt-rich waste feedstock for a higher lipid and DHA content as well as application of natural colouring agents in food products.