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Multifunctional fabrics of high durability through a scalable and eco-friendly technique remains a great challenge hindering their commercialization. In this work, we report a facile synthesis technique for the fabrication of superhydrophobic antibacterial fabrics by employing fluorine-free silane coupling agents as cross-linkers for enhanced durability. Three silane cross-linkers, Aminoethylaminopropyltrimethoxysilane (AEAPTMS), Aminopropyltriethoxysilane (APTES), and Methacryloyloxypropyltrimethoxysilane (MPTMS), have been investigated. During the fabrication, a low surface energy polymer, polydimethylsiloxane (PDMS) was first deposited on cotton fabrics. Subsequently, antibacterial copper oxide (CuO) nanoparticles were anchored on the PDMS coated fabrics using the silane cross-linkers. The as-prepared fabrics displayed high superhydrophobicity and antibacterial performance with water contact angle (WCA) > 153°, water shedding angle (WSA)

Vitamin D deficiency is a public health issue that not only results in skeletal disorders but is also linked to several chronic diseases. Several studies have shown that ultraviolet (UV)-treated mushrooms are a potential dietary source of vitamin D, as these mushrooms have a high rate of conversion of ergosterol to vitamin D2. However, there are gaps in knowledge about the most appropriate irradiation conditions, including the source, dose, intensity, and duration of irradiation, for maximizing vitamin D2 content in mushrooms. UVB seems to be most effective in transforming ergosterol to vitamin D2 in both fresh and dried mushrooms. Effects of drying, storage, and thermal treatments on vitamin D content in UV-treated fresh mushrooms have been reported. This knowledge is important for the mushroom industry in order to provide the market with vitamin D2-enhanced mushrooms in a safe and affordable manner. Recent studies in humans focused on the bioavailability of vitamin D2 from mushrooms. The study results showed that UV-treated mushrooms were effective in increasing serum 25-hydroxyvitamin D levels, as they contain high vitamin D2. However, other reports indicate that there are no significant changes in serum 25(OH)D levels and suggest that vitamin D2 is not as effective as vitamin D2 in increasing serum 25(OH) D levels. Vitamin D2 bioavailability is still unclear, and there is an urgent need to investigate the effectiveness, safety, and adequate amount of vitamin D2-enhanced mushrooms for reducing vitamin D deficiency and maintaining vitamin D levels.

Natural products are prolific producers of diverse chemical scaffolds, which have yielded several clinically useful drugs. However, the complex features of natural products present challenges for identifying bioactive molecules using high-throughput screens. For most assays, measured endpoints are either colorimetric or luminescence based. Thus, the presence of the major metabolites, tannins, and chlorophylls, in natural products could potentially interfere with these measurements to give either false-positive or false-negative hits. In this context, zebrafish phenotypic assays provide an alternative approach to bioprospect naturally occurring bioactive compounds. Whether tannins and/or chlorophylls interfere in zebrafish phenotypic assays, is unclear. In this study, we evaluated the interference potential of tannins and chlorophylls against efficacy of known small-molecule inhibitors that are known to cause phenotypic abnormalities in developing zebrafish embryos. First, we fractionated tannin-enriched fraction (TEF) and chlorophyll-enriched fraction (CEF) from Camellia sinensis and cotreated them with PD0325901 [mitogen-activated protein kinase-kinase (MEK) inhibitor] and sunitinib malate (SM; anti-[lymph]angiogenic drug). While TEF and CEF did not interfere with phenotypic or molecular endpoints of PD0325901, TEF at 100 μg/mL partially masked the antiangiogenic effect of SM. On the other hand, CEF (100 μg/mL) was toxic when treated up to 6 dpf. Furthermore, CEF at 100 μg/mL potentially enhanced the activity of γ-secretase inhibitors, resulting in toxicity of treated embryos. Our study provides evidence that the presence of tannin and/or chlorophyll in natural products do interfere with zebrafish phenotype assays used for identifying potential hits. However, this may be target/assay dependent and thus requiring additional optimization steps to assess interference potential of tannins and chlorophylls before performing any screening assay.

Anaerobic digestion has been widely employed in waste treatment for its ability to capture methane gas released as a product during the digestion. Certain wastes, however, cannot be easily digested due to their low nutrient level insufficient for anaerobic digestion, thus co-digestion is a viable option. Numerous studies have shown that using co-substrates in anaerobic digestion systems improve methane yields as positive synergisms are established in the digestion medium, and the supply of missing nutrients are introduced by the co-substrates. Nevertheless, large-scale implementation of co-digestion technology is limited by inherent process limitations and operational concerns. This review summarizes the results from numerous laboratory, pilot, and full-scale anaerobic co-digestion (ACD) studies of wastewater sludge with the co-substrates of organic fraction of municipal solid waste, food waste, crude glycerol, agricultural waste, and fat, oil and grease. The critical factors that influence the ACD operation are also discussed. The ultimate aim of this review is to identify the best potential co-substrate for wastewater sludge anaerobic co-digestion and provide a recommendation for future reference. By adding co-substrates, a gain ranging from 13 to 176% in the methane yield was accomplished compared to the mono-digestions.

Three main parameters of palm oil mill effluent (POME) i.e. biological oxygen demand (BOD), total suspended solids (TSS) and oil and grease (O&G), at high concentrations, have hindered efficient anaerobic digestion (AD) due to sludge flotation and scum formation. In this study, Moringa Oleifera extract was co-digested with POME to allow TSS and O&G to be coagulated and settled, and hence, an immobilisation media formed for better digestibility. Mono-digestion (POME, T1 and M. oleifera extract, T2, separately) served as control while co-digestion involved dosing 50 mL of M. oleifera extract (500 mg/L) into a fixed volume of POME (450 mL) at two feeding modes: daily, day 1 to day 30 (T3) and one-time, day 1 (T4). Treatments T1-T4 were conducted in an enclosed AD system for 30 days and the undesirable organic materials removal efficiencies i.e. BODremoval, TSSremoval and O&Gremoval were compared. POME co-digestion, T4, showed an improved 92% TSSremoval, 94% BODremoval and methane yield of 24.3 mL CH4/g COD removed. The results suggested that the nitrogen-fixing capabilities of anoxic microbial cells enhanced proliferation and growth encapsulated within the immobilisation media. Methanogen bacterial DNAs isolated from POME, granular sludge and anaerobically-treated POME were identified as Methanoculleus spp., Methanolinea spp. and Methanoculleus spp., respectively. Two-step complementary DNA (cDNA) and quantitative polymerase chain reaction (qPCR) confirmed the highest methanogen DNA concentration in T4. Therefore, the naturally occurring underutilised M. oleifera can be an organic coagulant for efficient POME co-digestion with an overall 69% and 59.5% higher methane yield and TSSremoval than mono-digestion.

Breast tumors are stiffer and more hypoxic than nonmalignant breast tissue. Here we report that stiff and hypoxic microenvironments promote the development of breast cancer stem-like cells (CSC) through modulation of the integrin-linked kinase ILK. Depleting ILK blocked stiffness and hypoxia-dependent acquisition of CSC marker expression and behavior, whereas ectopic expression of ILK stimulated CSC development under softer or normoxic conditions. Stiff microenvironments also promoted tumor formation and metastasis in ovo, where depleting ILK significantly abrogated the tumorigenic and metastatic potential of invasive breast cancer cells. We further found that the ILK-mediated phenotypes induced by stiff and hypoxic microenvironments are regulated by PI3K/Akt. Analysis of human breast cancer specimens revealed an association between substratum stiffness, ILK, and CSC markers, insofar as ILK and CD44 were expressed in cancer cells located in tumor regions predicted to be stiff. Our results define ILK as a key mechanotransducer in modulating breast CSC development in response to tissue mechanics and oxygen tension. Cancer Res; 76(18); 5277–87. ©2016 AACR.

Carbene-catalyzed reaction of carboxylic esters has the potential to offer effective synthetic solutions that cannot be readily achieved by using the more conventional aldehyde-type substrates. Here we report the first carbene-catalyzed dynamic kinetic resolution of α,α-disubstituted carboxylic esters with up to 99:1 er and 99% yield. The present study clearly illustrates the unique power of carbene-catalyzed reactions of readily available and easy to handle carboxylic esters. NRF (Natl Research Foundation, S’pore) MOE (Min. of Education, S’pore) Accepted version

Central serous chorioretinopathy (CSCR) is a retinal condition characterized by fluid accumulation in the subretinal space, resulting in neurosensory detachment or pigment epithelial detachment. The risk factors associated with this condition include male gender, middle age, smoking, stress and use of corticosteroids. We report a case of CSCR in a 37-year-old policeman with hypertension and bronchial asthma. He presented with sudden onset of bilateral blurring of central vision for 1 day, worse over the left eye. There were no other significant eye complaints. He is an active smoker and has been on long-term corticosteroids for asthma. On examination, the visual acuity was 6/9 bilaterally. The anterior segment of both eyes was normal. Examination of the right fundus revealed a dome-shaped swelling inferior to the fovea, while the left fundus showed circular detachment of the neurosensory retina at the macula. He was diagnosed to have bilateral central serous chorioretinopathy. He was also counseled to stop smoking. The corticosteroids were continued due to the risk of precipitating an asthma attack if they were withheld. Upon his next review two months later, his condition remained stable. CSCR is usually a self-limited condition, with good visual outcome. A thorough medical, social and drug history should be obtained, and patients advised to modify their lifestyle to eliminate or reduce risk factors such as smoking, stress and corticosteroid use.

We report a case series of dengue maculopathy with different ocular manifestations, managements, visual outcomes and sequelae of patients. All three cases were diagnosed to have dengue fever. Patients presented with symptoms of central scotoma (case 1 and case 3) and blurring of vision (case 2) on Day 9 of dengue fever. Fundus examination showed intra retinal haemorrhages (case 1 and case 2) and macula thickening (case 3). Optical coherence tomography (OCT) revealed macular thickening with intra retinal fluid (case 1) and diffuse retinal thickening (case 3), while in case 2, it had irregular ellipsoid line in OCT. Fundus fluorescence angiography (FFA) revealed parafoveal vasculitis. After treatment with systemic steroids, one patient had good visual outcome (case 2), while two others had a persistent central scotoma due to macula atrophy (case 3). Although it is a self limiting disease, but the mode of treatment is variable. Treatment with corticosteroids may hasten recovery of vision and prevent permanent visual impairment.

Oil and grease, carbohydrate, protein, and lignin are the main constituents of high strength wastewaters such as dairy wastewater, cheese whey wastewater, distillery wastewater, pulp and paper mill wastewater, and slaughterhouse wastewaters. These constituents have contributed to various operational problems faced by the high-rate anaerobic bioreactor (HRAB). During the hydrolysis stage of anaerobic digestion (AD), these constituents can be hydrolyzed. Since hydrolysis is known to be the rate-limiting step of AD, the overall AD can be enhanced by improving the hydrolysis stage. This can be done by introducing pretreatment that targets the degradation of these constituents. This review mainly focuses on the biological pretreatment on various high-strength wastewaters by using different types of enzymes namely lipase, amylase, protease, and ligninolytic enzymes which are responsible for catalyzing the degradation of oil and grease, carbohydrate, protein, and lignin respectively. This review provides a summary of enzymatic systems involved in enhancing the hydrolysis stage and consequently improve biogas production. The results show that the use of enzymes improves the biogas production in the range of 7 to 76%. Though these improvements are highly dependent on the operating conditions of pretreatment and the types of substrates. Therefore, the critical parameters that would affect the effectiveness of pretreatment are also discussed. This review paper will serve as a useful piece of information to those industries that face difficulties in treating their high-strength wastewaters for the appropriate process, equipment selection, and design of an anaerobic enzymatic system. However, more intensive studies on the optimum operating conditions of pretreatment in a larger-scale and synergistic effects between enzymes are necessary to make the enzymatic pretreatment economically feasible.

Cells communicate constantly with their surrounding extracellular matrix (ECM) to maintain homeostasis, using both mechanical and chemical signals. In cancer, abnormal signaling leads to stiffening of the ECM. A stiff microenvironment affects many aspects of the cell, including internal molecular signaling as well as behaviors such as motility and proliferation. Thus, cells and ECM interact in a feedback loop to drive matrix deposition and cross-linking, which alter the mechanical properties of the tissue. Stiffer tissue enhances the invasive potential of a tumor and decreases therapeutic efficacy. This chapter describes how specific molecular effects caused by an abnormally stiff tissue drive macroscopic changes that help determine disease outcome. A complete understanding may foster the generation of new cancer therapies.

This study investigates the long-term effects of deoxynivalenol (DON) consumption on avian growth performance, on the proliferation, apoptosis, and DNA damage of spleen cells, and on intestinal integrity. Two hundred and eight 5-day-old black-feathered Taiwan country chickens were fed diets containing 0, 2, 5, and 10 mg/kg of DON for 16 weeks. Body weight gain of male birds in the 2 mg/kg group was significantly lower than that in the 5 mg/kg group. At the end of trial, feeding DON-contaminated diets of 5 mg/kg resulted in heavier spleens. Moreover, the increase in DON induced cellular proliferation, apoptosis, and DNA damage signals in the spleen, the exception being female birds fed 10 mg/kg of DON showing reduced proliferation. Expression of claudin-5 was increased in jejunum of female birds fed 2 and 5 mg/kg of DON, whereas decreased expression levels were found in male birds. In conclusion, our results verified that DON may cause a disturbance to the immune system and alter the intestinal barrier in Taiwan country chickens, and may also lead to discrepancies in growth performances in a dose- and sex-dependent manner.

The production of natural biopolymers as flocculants for water treatment is highly desirable due to their inherent low toxicity and low environmental footprint. In this study, bio-flocculants were extracted from Hibiscus/Abelmoschus esculentus (okra) by using a water extraction method, and the extract yield and its performance in sludge dewatering were evaluated. Single factor experimental design was employed to obtain the optimum conditions for extraction temperature (25–90 °C), time (0.25–5 h), solvent loading (0.5–5 w/w) and agitation speed (0–225 rpm). Results showed that extraction yield was affected non-linearly by all experimental variables, whilst the sludge dewatering ability was only influenced by the temperature of the extraction process. The optimum extraction conditions were obtained at 70 °C, 2 h, solvent loading of 2.5 w/w and agitation at 200 rpm. Under the optimal conditions, the extract yield was 2.38%, which is comparable to the extraction of other polysaccharides (0.69–3.66%). The bio-flocculants displayed >98% removal of suspended solids and 68% water recovery during sludge dewatering, and were shown to be comparable with commercial polyacrylamide flocculants. This work shows that bio-flocculants could offer a feasible alternative to synthetic flocculants for water treatment and sludge dewatering applications, and can be extracted using only water as a solvent, minimising the environmental footprint of the extraction process.

Using a membrane reactor for reversible transesterification reaction involves reaction and product separation within a single unit. However, a pseudohomogeneous reaction and heterogeneous separation must be maintained for successful membrane reactor operation. Present research is aimed to develop an integrated model of chemical and phase equilibrium (CPE) and modified Maxwell–Stefan equation that describes the simultaneous CPE and mass transport phenomena of biodiesel production from crude palm oil (CPO) using a membrane reactor. In the first part of this work, a systematic approach describing simultaneous CPE of CPO transesterification in the membrane reactor was developed with the reconciliation of transesterification reaction and phase equilibrium that involves six-component. The results revealed that regressed apparent equilibrium constant, Keq value of 17.557 ±1.51% were higher than the literatures. This indicates that forward reaction of the reversible CPO transesterification is much favored in the membrane reactor than the conventional reactor. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1968–1980, 2015

The mechanistic modeling of biodiesel production process in membrane reactor with the consideration of chemical reaction, phase equilibrium, and ultrafiltration is important for the membrane reactor design. In part II of this work, the chemical and phase equilibrium (CPE) model for crude palm oil transesterification reaction in the membrane reactor developed in part I is extended to an integration of CPE with modified Maxwell–Stefan model, which considers multicomponent mass transport phenomena of concentration polarization and intramembrane. A good fit of simulated permeate fluxes and apparent solute rejection to the experimental data shows that the model has a good prediction capability. Reversible fouling was found to be the major fouling and no pore plugging was observed. Simulation results verified that micelles were retained by the membrane at CPO:MEOH molar ratio of 1:24 and catalyst concentration of 0.5 wt %. However, phase inversion happened when catalyst concentration of 0.05 and 0.1 wt % were used. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1981–1996, 2015

Synthesis of 3-fluoro-2-hetarylindoles through addition of hetarenes to 3,3-difluoroindolium ions generated in situ by Zn(OTf)2-catalyzed oxazolidine ring opening is described. Indoles, pyrroles and alkyl-substituted furans can be used as hetaryl nucleophiles to afford a range of 3-fluoro-2-hetarylindole products 6 in 56–95 % yields. A diverse array of 3,3-difluorinated 2-hetarylindolines 7 can also be synthesized in 43–84 % yields by a tandem sequential process that involves hetarene nucleophilic addition, HF elimination and fluorocyclization reactions. Our study by 1H NMR and UV/Vis spectroscopy reveals that 3,3-difluorinated 2-hetarylindolines possess interesting substituent-dependent acidochromic properties. UV absorption and fluorescence spectra of selected compounds 6 and 7 are also studied.

Flocculation is an essential phenomenon in industrial wastewater treatment. Inorganic coagulants (salts of multivalent metals) are being commonly used due to its low cost and ease of use. However, their application is constrained with low flocculating efficiency and the presence of residue metal concentration in the treated water. Organic polymeric flocculants are widely used nowadays due to its remarkable ability to flocculate efficiently with low dosage. However, its application is associated with lack of biodegradability and dispersion of monomers residue in water that may represent a health hazard. Therefore, biopolymers based flocculants have been attracting wide interest of researchers because they have the advantages of biodegradability and environmental friendly. But, natural flocculants are needed in large dosage due to its moderate flocculating efficiency and shorter shelf life. Thus, in order to combine the best properties of both, synthetic polymers are grafted onto the backbone of natural polymers to obtain tailor-made grafted flocculants. This paper gives an overview of the development of different types of flocculants that were being investigated for treatment of industrial wastewater. Furthermore, their flocculation performance will be reviewed and the flocculation mechanism will be discussed.

Background: Hyperkalaemia has been reported with high-dose trimethoprim (20 mg/kg/day) and standard-dose trimethoprim (6 mg/kg/day) plus sulfamethoxazole use. Aim: To investigate changes in plasma potassium concentrations in patients prescribed standard-dose trimethoprim 300 mg daily for urinary tract infections. Method: A retrospective cohort study of hospital patients with urinary tract infections treated with trimethoprim or other antibacterials (control group) for more than 5 days. Plasma potassium concentration, creatinine and urea were compared at baseline and at the completion of treatment. Results: There were 31 patients in the trimethoprim group and 65 patients in the control group. End-of-therapy mean plasma potassium concentrations increased significantly from baseline in the trimethoprim group (4.2 plus or minus 0.4 mmol/L to 4.5 plus or minus 0.5 mmol/L; p = 0.002) but not in the control group. End-of-therapy mean plasma potassium concentrations were also higher in the trimethoprim group (4.5 plus or minus 0.5 mmol/L vs 4.2 plus or minus 0.5 mmol/L; p = 0.007). 65% of the trimethoprim group developed end-of-therapy hyperkalaemia versus 39% of the control group. Mean creatinine concentration in the trimethoprim group increased by an average of 21% from baseline but did not change in the control group. The trimethoprim group showed no change in mean urea concentration but a decrease was noted in the control group. Conclusion: Treating urinary tract infections with trimethoprim 300 mg daily for more than 5 days was associated with an increase in plasma potassium concentration.

Upflow anaerobic sludge blanket-hollow centered packed bed (UASB-HCPB) reactor was developed with the aim to minimize operational problems in the anaerobic treatment of Palm Oil Mill Effluent (POME) under thermophilic conditions. The performance of UASB-HCPB reactor on POME treatment was investigated at 55 °C. Subsequent to start-up, the performance of the UASB-HCPB reactor was evaluated in terms of i) effect of hydraulic retention time (HRT); ii) effect of organic loading rate (OLR); and iii) effect of mixed liquor volatile suspended solid (MLVSS) concentration on thermophilic POME treatment. Start-up up of the UASB-HCPB reactor was completed in 36 days, removing 88% COD and 90% BOD respectively at an OLR of 28.12 g L−1 d−1, producing biogas with 52% of methane. Results from the performance study of the UASB-HCPB reactor on thermophilic POME treatment indicated that HRT of 2 days, OLR of 27.65 g L−1 d−1 and MLVSS concentration of 14.7 g L−1 was required to remove 90% of COD and BOD, 80% of suspended solid and at the same time produce 60% of methane.

Palm Oil Mill Effluent (POME) treatment has always been a topic of research in Malaysia. This effluent that is extremely rich in organic content needs to be properly treated to minimize environmental hazards before it is released into watercourses. The main aim of this work is to evaluate the potential of applying natural, chemically and thermally modified banana peel as sorbent for the treatment of biologically treated POME. Characteristics of these sorbents were analyzed with BET surface area and SEM. Batch adsorption studies were carried out to remove color, total suspended solids (TSS), chemical oxygen demand (COD), tannin and lignin, and biological oxygen demand (BOD) onto natural banana peel (NBP), methylated banana peel (MBP), and banana peel activated carbon (BPAC) respectively. The variables of pH, adsorbent dosage, and contact time were investigated in this study. Maximum percentage removal of color, TSS, COD, BOD, and tannin and lignin (95.96%, 100%, 100%, 97.41%, and 76.74% respectively) on BPAC were obtained at optimized pH of 2, contact time of 30 h and adsorbent dosage of 30 g/100 ml. The isotherm data were well described by the Redlich-Peterson isotherm model with correlation coefficient of more than 0.99. Kinetic of adsorption was examined by Langergren pseudo first order, pseudo second order, and second order. The pseudo second order was identified to be the governing mechanism with high correlation coefficient of more than 0.99.

A scalable procedure for the title transformation of a broad range of α,α-disubstituted carboxylic esters is developed which delivers the products in often very high yields and with very high enantiomeric purity.

Cells are surrounded by mechanical stimuli in their microenvironment. It is important to determine how cells respond to the mechanical information that surrounds them in order to understand both development and disease progression, as well as to be able to predict cell behavior in response to physical stimuli. Here we describe a protocol to determine the effects of interstitial fluid flow on the migratory behavior of an aggregate of epithelial cells in a three-dimensional (3D) culture model. This protocol includes detailed methods for the fabrication of a 3D cell culture chamber with hydrostatic pressure control, the culture of epithelial cells as an aggregate in a collagen gel, and the analysis of collective cell behavior in response to pressure-driven flow.

Boron removal from synthetic wastewater by using palm oil mill boiler (POMB) ash impregnated with various chemical compounds (citric acid, tartaric acid, salicylic acid, barium chloride, calcium chloride anhydrous, and calcium chloride dihydrate) was being investigated in this study. The characteristics of POMB ash were analyzed based on ash content, carbon content, and BET surface area. The adsorption process was performed in a batch system with various parameters: dosage of POMB ash, residence time, shaking speed, temperature, and pH. The results show that impregnants increased the ability of POMB ash to adsorb boron, and the adsorption efficiency of boron was highly dependent on the pH. The optimization study shows that citric acid was the optimum impregnant on the POMB ash, with maximum boron removal efficiency of 65.69% at dosage of 6 g/50 mL at pH 7.0 with shaking speed of 100 rpm at 25 °C and 12 h of residence time.

Transesterification of oils/triglycerides (TGs) with alcohol in the presence of catalyst has been the most commonly used process to produce biodiesel. Major limiting factors of conventional biodiesel transesterification process are phase separation and product purification. Precise and correct knowledge of the phase equilibrium behaviour is crucial for future industrial biodiesel reaction, separation and purification processes. For this purpose, it is important to consider the phase equilibrium behaviour in order to thoroughly understand the entire transesterification system for biodiesel production, which consists of six components. This work is to discuss on the liquid–liquid equilibrium (LLE) data of six-component system which involves TG, palm biodiesel (FAME), methanol (MeOH), glycerine (GLY), diglyceride (DG) and monoglyceride (MG). The phase equilibrium data of this system were determined experimentally through transesterification of crude palm oil (CPO). The experimental LLE data have been transposed into a pseudo-ternary diagram as TG–DG–MG + MeOH–GLY + FAME for better visualisation and understanding of the six-component system. Results showed that the transesterification of TG to FAME has formed a two-phase system where CPO-rich phase and MeOH-rich phase co-existed during the reaction. Due to immiscibility of CPO and MeOH, as well as the miscibility of FAME and MeOH, the LLE data suggested that at specific reaction operating condition, the reacted product (FAME) could be continuously removed by separating the MeOH phase from the CPO phase. This favours the forward transesterification reaction and eventually enhances the reaction efficiency to produce an oil-free FAME.

This work presents the evaluation of biokinetic coefficients for a novel integrated anaerobic-aerobic bioreactor (IAAB) at different organic loading rates (OLRs) (10.5-22.5 g COD/L per day) treating palm oil mill effluent. The overall efficiencies of the chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were more than 99% for OLR up to 19.5 g COD/L day with biogas production containing 48-64% of methane. The effluent quality remained stable (BOD 80 mg/L) and satisfied with the discharge limit. Stover-Kincannon model was the most appropriate model to estimate the performance of anaerobic compartment of IAAB, while Monod model was best suited for describing the aerobic compartment.BOD: biochemical oxygen demand; COD: chemical oxygen demand; DO: dissolved oxygen; GLSS: gas-liquid-solid separator; MLSS: mixed liquor suspended solid; MLVSS: mixed liquor volatile suspended solid; POME: palm oil mill effluent; RAS: returned activated sludge; SBR: sequencing batch reactor; SVI: sludge volume index; TA: total alkalinity; TN: total nitrogen; TS: total solids; TSS: total suspended solids; UASB: upflow anaerobic sludge blanket; UASFF: upflow anaerobic sludge blanket fixed film; VFA: volatile fatty acid; VSS: volatile suspended solids.

Recently, membrane reactor technology was used to produce high-quality biodiesel because of its advantage of simultaneous transesterification and separation. As the transesterification reaction involves two immiscible phases of methanol (MeOH) and oil (TG), a thorough investigation on the membrane reactor for biodiesel production with the consideration of chemical phase equilibrium (CPE) via modeling analysis, was conducted in this study. A mathematical model was developed based on the modified Maxwell-Stefan model with the incorporation of CPE. The formation of TG rich micelles dispersed in the continuous phase of MeOH was the most important hypothesis in the model development. The preliminary experiment results show that the permeate compositions from the membrane reactor were closely related to CPE of the system, which was highly depending on the MeOH to TG molar ratio. TG free permeate can only be obtained if the continuous phase of MeOH was free from TG and the TG rich micelles were retained by the membrane. The model verification further confirmed the formation of micelles dispersed in the continuous MeOH phase within the feed side of the membrane reactor and the model was able to predict the performance of the membrane reactor for biodiesel production at an acceptable accuracy. © 2012 American Institute of Chemical Engineers AIChE J, 59: 258–271, 2013

This research is aimed at improving the thermophilic aerobic treatment system of anaerobically digested palm oil mill effluent (POME) through optimization of mixed liquor suspended solids (MLSS) at high concentration range for the first time besides other parameters of organic loading rate (OLR), dissolved oxygen (DO) concentrations and settling time. Chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total suspended solids (TSS) removal ratios were measured as indicators of the system performance. Experimental results clearly indicate that MLSS and OLR are the crucial parameters in thermophilic aerobic treatment. Optimal COD, BOD and TSS removals up to 86%, 87% and 89%, respectively, were achieved with MLSS concentration and OLR of 27,000 mg/L and 2.5 g COD/(L day), respectively. More significantly, high MLSS concentration range which is yet to be reported was successfully applied and this has resulted in superior performance as compared to other thermophilic treatment studies. No significant improvement of the treatment efficiency was attained with DO concentration exceeding 5 mg/L and settling time up to 24 h. Hence, operation at DO concentration of 2 mg/L and settling time of 2 h gives a good compromise between effluent quality and system operating costs.

The aim of this study is to investigate the rumen ecology and feed digestion in Formosan Reeves’ muntjac (Muntiacus reevesi micrurus). We also observed the effect of captive environment on animal digestive physiology by comparing the characteristics of gastrointestinal tract and tissue samples of ruminal papillae between captive and wild muntjac. Results revealed that the pH value of rumen fluids of captive muntjac was 6.44 and the concentration of volatile fatty acid, which was lower than that of the domestic animal. The rumen total bacteria count was 1.35×108 colony counts/mL rumen fluids. The percentage of Isotrichidae in total protozoa population was lower than 20%, whereas Ophryoscolecidae was greater than 80%. The ratio of intestinal length to body length was approximately 13.9:15.1 which was similar to the concentrate selector. The morphology of ruminal papillae showed distinct difference between captive and wild muntjacs, and the length of small intestinal tract tended to be longer in captive munt...

Palm oil mill effluent (POME) is a wastewater generated from palm oil milling activities which requires effective treatment before discharge into watercourses due to its highly polluting properties. The characterization of wastewater is the essential step in the design of any wastewater treatment plant (WWTP) in the industry as conducting pilot-scale tests to obtain design and operating parameters is time-consuming and expensive. Characterization of POME had been conducted in various studies which only involve parameters that were listed as discharge standards by local environmental authorities and those that were significant to the results of the chosen treatment methods. Other important parameters that were seldom considered in the characterization of POME are as follows: total phosphorus (TP), total organic carbon (TOC), total Kjeldahl nitrogen (TKN), total volatile solids (TVS), volatile suspended solids (VSS), lignin and sulfate concentrations, and toxicity. These parameters are very important in det...

Anaerobic systems operated under thermophilic condition often encounter longer start-up period and operating problems pertaining to temperature shift when mesophilic seed sludge were utilized as thermophilic sludge. Bioaugmentation products for thermophilic conditions were not readily available in the market. Hence, a thermophilic mixed culture has been cultivated specifically for Palm Oil Mill Effluent (POME) treatment at thermophilic conditions using a batch Continuous Stirred Tank Reactor (CSTR) where POME was utilized as a substrate for the growth of microbes. The thermophilic mixed culture managed to reduce at least 90% of Chemical Oxygen Demand (COD) in POME with a hydraulic retention time (HRT) of 6 days with a MLSS concentration of 14,000 mg/L. The biogas produced from the batch CSTR contained at least 64% of methane. The kinetic parameters for batch thermophilic POME treatment were obtained by fitting the Chen and Hashimoto's model to the experimental data. The maximum substrate utilization rate for this system was found to be 0.476 day −1 , which was higher than the systems operated under mesophilic range, and dimensionless kinetic parameters k and Q were −1.365 and 0.0007 respectively. The mixed culture had a methanogenic population which consisted of Methanosaeta thermophila , Methanosarcina thermophila , Methanobacterium thermoautotrophicum , Methanobacterium thermoformicicum and Methanobacterium wolfei .

Aerobic treatment of wastewater under thermophilic conditions has received growing interest in recent years. Because of the high discharge temperature (75 to 85 °C) of palm oil mill effluent (POME), it would be more economical if POME were treated thermophilically, as then cooling facilities prior to biological treatment can be eliminated. In the present investigation, the feasibility of thermophilic aerobic biological treatment as a suitable post-treatment system for anaerobically treated POME was examined. Also, the effects of temperature on the treated effluent quality were investigated by using sequencing batch reactors (SBRs) under mesophilic (28 °C) and thermophilic (45, 50, and 55 °C) conditions. The average total COD (TCOD) removal efficiencies varied from 55 to 98% at organic loading rates (OLR) of 2.6 to 4.5 kg COD/m3·day, dissolved oxygen (DO) concentrations of 2.9−4.5 mg/L, and mixed-liquor suspended solids (MLSS) concentrations of 22500−24200 mg/L. The results show that the thermophilic aerob...

Boron is extensively used in the ceramic industry for enhancing mechanical strength of the tiles. The discharge of boron containing wastewater to the environment causes severe pollution problems. Boron is also dangerous for human consumption and causes organisms' reproductive impediments if the safe intake level is exceeded. Current methods to remove boron include ion-exchange, membrane filtration, precipitation–coagulation, biological and chemical treatment. These methods are costly to remove boron from the wastewater and hence infeasible for industrial wastewater treatment. In the present research, adsorption–flocculation mechanism is proposed for boron removal from ceramic wastewater by using Palm Oil Mill Boiler (POMB) bottom ash and long chain polymer or flocculant. Ceramic wastewater is turbid and milky in color which contains 15 mg/L of boron and 2000 mg/L of suspended solids. The optimum operating conditions for boron adsorption on POMB bottom ash and flocculation using polymer were investigated in the present research. Adsorption isotherm of boron on bottom ash was also investigated to evaluate the adsorption capacity. Adsorption isotherm modeling was conducted based on Langmuir and Freundlich isotherms. The results show that coarse POMB bottom ash with particle size larger than 2 mm is a suitable adsorbent where boron is removed up to 80% under the optimum conditions (pH = 8.0, dosage = 40 g bottom ash/300 ml wastewater, residence time = 1 h). The results also show that KP 1200 B cationic polymer is effective in flocculating the suspended solids while AP 120 C anionic polymer is effective in flocculating the bottom ash. The combined cationic and anionic polymers are able to clarify the ceramic wastewater under the optimum conditions (dosage of KP 1200 B cationic polymer = 100 mg/L, dosage of AP 120 C anionic polymer = 50 mg/L, mixing speed = 200 rpm). Under the optimum operating conditions, the boron and suspended solids concentration of the treated wastewater were reduced to 3 mg/L and 5 mg/L respectively, satisfying the discharge requirement by Malaysia Department of Environment (DOE). The modeling study shows that the adsorption isotherm of boron onto POMB bottom ash conformed to the Freundlich Isotherm. The proposed method is suitable for boron removal in ceramic wastewater especially in regions where POMB bottom ash is abundant.

Palm oil mill effluent (POME) is a highly polluting wastewater that pollutes the environment if discharged directly due to its high chemical oxygen demand (COD) and biochemical oxygen demand (BOD) concentration. Anaerobic digestion has been widely used for POME treatment with large emphasis placed on capturing the methane gas released as a product of this biodegradation treatment method. The anaerobic digestion method is recognized as a clean development mechanism (CDM) under the Kyoto protocol. Certified emission reduction (CER) can be obtained by using methane gas as a renewable energy. This review aims to discuss the various anaerobic treatments of POME and factors that influence the operation of anaerobic treatment. The POME treatment at both mesophilic and thermophilic temperature ranges are also analyzed.

Selective gold adsorption was investigated for the NH 2 -MCM-41 and SH-MCM-41 adsorbents prepared by grafting aminopropyl and thiolpropyl groups on the surface of the MCM-41 mesoporous silica. The single component adsorption of gold, copper and nickel from salt solutions, and the binary adsorption studies of Au 3+ /Cu 2+ and Au 3+ /Ni 2+ solutions were carried out for the two adsorbents. Gold adsorption from simulated gold mining solution and gold electroplating wastewater were also reported. The NH 2 -MCM-41 and SH-MCM-41 displayed strong affinity for gold in the solution and both exhibited 100% selectivity for the gold in the binary Au 3+ /Cu 2+ and Au 3+ /Ni 2+ solutions. The NH 2 -MCM-41 is more suitable for the gold mining solution, while SH-MCM-41 is efficient for gold adsorption from the electroplating waste containing high amount of organics. The gold was recovered as high purity salt solution by elution with mineral acid for NH 2 -MCM-41 and thiolsulfate for SH-MCM-41. The regenerated adsorbent remained selective to gold and exhibited the same adsorption capacity as the fresh adsorbent. Also, the regenerated adsorbent performed well even after several reuses.

The present study is intended for the first time to completely replace the inorganic coagulants with organic polymers in palm oil mill effluent (POME) pretreatment by using direct flocculation of single and dual polymer systems under applied shear. The efficiency of direct flocculation of POME was investigated by using the Population Balance Model (PBM) which considered the charge neutralization and bridging attraction under applied shear. The collision efficiency was calculated based on the Derjaguin Landau Verwey Overbeek (DLVO) theory which considered the effect of adsorbed polymer layers on van der Waals attraction and bridging attraction. This is the first attempt to correlate the floc size distribution from PBM to the indirect indicators of COD, suspended solids, oil and grease. The model predictions are in close agreement with the experimental results for both single and dual polymer systems. The interaction energy curves based on PBM shows that the flocculation using cationic polymer is by charge neutralization and bridging attraction whereas flocculation using anionic polymer is by only bridging attraction. At the optimum flocculation conditions, 99.66%, 55.79%, 99.74% and 80.78% of suspended solids, COD, oil and grease removal and water recovery are achieved, respectively. The direct flocculation process significantly reduced the treatment cost by a factor of 3.6 compared to the conventional coagulation–flocculation process.

The mesoporous NH2-MCM-41 adsorbent prepared by grafting aminopropyls on MCM-41 is selective towards gold and palladium adsorptions and can separate these precious metals from complex solutions containing other metal ions such as cobalt, nickel, copper and zinc. Adsorption is rapid and the adsorbent’s capacity for gold is better or comparable to most carbonaceous adsorbents including activated carbons. Furthermore, NH2-MCM-41 can separate palladium from gold solution at pH1.0 with excellent selectivity and capacity. Thus, it is possible to design a two steps separation process for the separation of palladium and then gold from the complex solution. A simple acid wash was sufficient to recover the adsorbed palladium and gold as concentrated, high purity (i.e., > 95%) metal salt solutions and the regenerated adsorbent was reused without lost of performance.

Four lipid-core peptide systems were synthesized using stepwise solid-phase peptide synthesis, incorporating a sequence from the human papillomavirus type-16 (HPV-16) E7 protein (E744-62), for the purpose of developing vaccines against HPV-16 associated cervical cancer. d-Mannose was conjugated to the vaccine in order to investigate whether the targeting of dendritic cell mannose receptors would improve vaccine efficacy. The ability of the vaccines to clear or reduce the size of HPV-16 associated tumors was assessed in C57BL/6 (H-2b) mice using the TC-1 HPV-16 tumor model. Overall, significant reductions in the size of TC-1 tumors were observed in the mouse model, with the conjugation of mannose to these vaccines demonstrated to clear or reduce the size of TC-1 tumors to a greater extent than non-mannose-containing vaccines (37 out of 40 versus 21 out of 30 tumors cleared, respectively).

The synthesis of various 3-fluoro-2-hetarylindoles through addition of indoles, pyrroles, or alkyl-substituted furans to 3,3-difluoroindolium ions generated in situ by zinc triflate-catalyzed oxazolidine ring opening is described.

The adsorption of pretreated palm oil mill effluent (POME) onto a granular activated carbon (GAC) fixed bed has been studied using the incorporation of ideal adsorbed solution theory (IAST) into the homogeneous surface diffusion model (HSDM). The pretreated POME is a complex solution of a ternary system containing three major organic solutes of carbohydrate constituents, protein, and ammoniacal nitrogen. The incorporation of IAST into HSDM allows multicomponent adsorption predictions using single-solute equilibrium isortherms. Batch adsorption and fixed-bed adsorption were conducted to obtain the experimental data for a multicomponent adsorption system using pretreated POME. The residence time in the bed was varied by manipulating the bed length and the feed flowrate. On the basis of the comparison of the experimental breakthrough curves with the simulation results, IAST gives a good prediction of multicomponent adsorption on GAC when it is incorporated into HSDM.

The aim of this study was to investigate methods for the synthesis of highly pure, well-characterized analogues of the lipid core peptide (LCP) system. Difficulties synthesizing and purifying conventional LCP systems have led to the requirement for a technique to produce highly pure, LCP-based vaccines for potential use in human clinical trials. The current study describes methods for the attachment of lipophilic adjuvants onto multi-epitopic peptide vaccines. Described is the synthesis, using native chemical ligation, of a highly pure, tri-epitopic, group A streptococcal (GAS) lipopeptide vaccine candidate. Intranasal immunization of the described tri-epitopic GAS lipopeptide with the mucosal adjuvant cholera toxin B subunit induced high serum IgG antibody titers specific for each of the incorporated peptide epitopes.

A mathematical model suitable for the multiple solutes system in continuous cross-flow ultrafiltration is developed. This model is based on mass balance analysis coupled with the filtration theory (osmotic pressure model, Kozeny–Carman equation), resistance-in-series model and gel polarization model. This model is characterized by the parameters R m , P m , K b , K bi and k i . These parameters are estimated by using the Levenberg–Marquardt method coupled with the Gauss–Newton algorithm based on the experimental data obtained from the treatment of pretreated palm oil mill effluent (POME) as a feed in the pilot plant scale ultrafiltration system. The pretreated POME is composed of a ternary system with the solutes of carbohydrate constituents, crude protein and ammoniacal nitrogen. The simulation results show a good agreement with the experimental data. The proposed model is suitable for predicting the performance of multiple solutes in an ultrafiltration process. The concentration of each solute present is correlated with the COD value of the permeate stream.

Group A streptococcus (GAS) is responsible for causing many clinical complications including the relatively benign streptococcal pharyngitis and impetigo. However, if left untreated, these conditions may lead to more severe diseases such as rheumatic fever (RF) and rheumatic heart disease (RHD). These diseases exhibit high morbidity and mortality, particularly in developing countries and in indigenous populations of affluent countries. As RF and RHD only ever occur following GAS infection, a vaccine offers promise for their prevention. As such, we have investigated the use of the lipid-core peptide (LCP) system for the development of multi-valent prophylactic GAS vaccines. The current study has investigated the capacity of this system to adjuvant up to four different GAS peptide epitopes. Presented are the synthesis and immunological assessment of tetra-valent and tri-valent GAS LCP systems. We demonstrated their capacity to elicit systemic IgG antibody responses in B10.BR mice to all GAS peptide epitopes. The data also showed that the LCP systems were self-adjuvanting. These findings are particularly encouraging for the development of multi-valent LCP-based GAS vaccines.

Synthesis of a tri-epitopic Group A streptococcal lipopeptide vaccine was achieved using native chemical ligation. The vaccine was administered intranasally to B10.BR mice, (H-2 k ) with cholera toxin B-subunit (CTB) or sterile phosphate-buffered saline. Following five boosts, blood was collected for ELISA. Significant IgG antibody titres were observed to the included peptide epitopes following administration with CTB. However, no significant IgG titres were observed in the absence of CTB.

Flocculation is extensively employed for clarification through sedimentation. Application of eco-friendly plant-based bioflocculants in wastewater treatment has attracted significant attention lately with high removal capability in terms of solids, turbidity, color, and dye. However, moderate flocculating property and short shelf life restrict their development. To enhance the flocculating ability, natural polysaccharides derived from plants are chemically modified by inclusion of synthetic, nonbiodegradable monomers (e.g., acrylamide) onto their backbone to produce grafted bioflocculants. This review is aimed to provide an overview of the development and flocculating efficiencies of plant-based bioflocculants and grafted bioflocculants for the first time. Furthermore, the processing methods, flocculation mechanism, and the current challenges are discussed. All the reported studies about plant-derived bioflocculants are conducted under lab-scale conditions in wastewater treatment. Hence, the possibility to apply natural bioflocculants in food and beverage, mineral, paper and pulp, and oleo-chemical and biodiesel industries is discussed and evaluated.

Poor prognosis of most cancer patients is in part, due to limited therapeutic options. Furthermore, as chemotherapy remains the standard-of-care for several cancers, partial or lack of response remains a concern and compounding this are the adverse side effects of the treatment that severely impacts the quality of life and survival. In pursuit of improving treatment options, we have opted to investigate the unique chemical skeleton of natural compounds as anticancer therapies. In this study, from an initial screen of 31 crude methanol extracts from ~15 plant species using HL60 cells, the root extract of Brucea javanica (L.) Merr indicated the presence of bioactive compounds. Subsequent bioassay-guided purification on the root extract yielded two alkaloids canthin-6-one (1) and bruceolline J (2), which were further investigated for their bioactivity in representative human cancer lines and normal phenotypic counterparts. MTT assay demonstrated ED50values from 34.7–72.9 μM for 1 and 16.0–54.0 μM for 2 for the cancer cell lines panel. NP69 cells also demonstrated sensitivity to both compounds (9.3 μM and 4.5 μM). As amount of 2 isolated were limiting, we focused on 1 to further identify novel anticancer properties in PC3 and HeLa cancer lines. We observed at 30 μM, 1 induced a G2/M phase arrest coinciding with decreased cell proliferation. Furthermore, 1 was able to synergize the cytotoxic effect of cisplatin when used in combination, suggesting the potential of combination therapy for those less responsive lesions to standard chemotherapy.

A diverted total synthesis (DTS) approach to the total synthesis of pyridone alkaloids N-deoxymilitarinone A (8) and torrubiellone B (10) has been developed. The common intermediate 14 was first assembled by a dual directed orthometalation process using a methoxymethyl group as directed metalation group. Other crucial steps include the assembly of polyenes under aldol condensation for DTS using general and concise strategy and diastereoselective synthesis of the syn-dimethyl array by an Evans aldol reaction.

Precise modification of the human genome has been a goal of researchers for over two decades. Currently, genome modification is performed by either transient or stable delivery of nucleic acids that encode genome modifying components to target cells. This nucleic-acid-based approach has a number of drawbacks, including low efficiency, toxicity, prolonged expression, off target effects, and potential delay in modification due to transcription and translation post-delivery. An alternative approach is direct intracellular delivery of genome-modifying proteins to live cells. This method allows both the timing and dose of target protein to be tightly controlled, thereby improving efficiency. Consistent with this, it has been reported that direct Cas9 protein delivery leads to higher levels of on-target editing and fewer off-target effects (eLife 2014;10.7554/eLife.04766). Direct protein delivery, however, is limited by the need to express and purify protein in E. coli, where issues with protein yield, proper folding, lack of post-translational modification may ultimately reduce activity. The use of recombinant protein is further complicated by a lack of efficient and consistent delivery methods into target cells of interest. Improved methods, combining mammalian based protein production and efficient packaging into particles into one step can address these shortcomings. Here we report cellular delivery of DNA modifying proteins using VSV-G induced microvesicles (Gesicles). Gesicles are produced by co-overexpression of the spike glycoprotein of VSV-G with a protein of interest (POI), within a mammalian packaging cell. This leads to production of Gesicles containing active amounts of the POI expressed in mammalian cells. Based on this principle, we have developed a method for actively packaging genome modifying proteins into the Gesicles via ligand dependent dimerization. This approach allowed us package a POI containing a nuclear localization signal (NLS) efficiently into this particle. Analysis of the physical properties of these Gesicles demonstrated that they are highly stable over multiple freeze-thaw cycles, are consistent in size, and demonstrate minimal aggregation. Functionally, these Gesicles could efficiently deliver genome modifying proteins to a variety of cells, ultimately leading to genomic alterations. This effect could be demonstrated in over a dozen different cell lines; in all cases, cells maintained high viability and the results closely mimicked those obtained with viral transduction. Taken together, this work suggests that Gesicles can be considered a novel and universal tool for genome modification, providing a direct, rapid, and transient method for delivering active genome modifying proteins to target cells.

SummaryAngiogenesis, the process by which new blood vessels arise from preexisting ones, is critical for embryonic development and is an integral part of many disease processes. Recent studies have provided detailed information on how angiogenic sprouts initiate, elongate, and branch, but less is known about how these processes cease. Here, we show that S1PR1, a receptor for the blood-borne bioactive lipid sphingosine-1-phosphate (S1P), is critical for inhibition of angiogenesis and acquisition of vascular stability. Loss of S1PR1 leads to increased endothelial cell sprouting and the formation of ectopic vessel branches. Conversely, S1PR1 signaling inhibits angiogenic sprouting and enhances cell-to-cell adhesion. This correlates with inhibition of vascular endothelial growth factor-A (VEGF-A)-induced signaling and stabilization of vascular endothelial (VE)-cadherin localization at endothelial junctions. Our data suggest that S1PR1 signaling acts as a vascular-intrinsic stabilization mechanism, protecting developing blood vessels against aberrant angiogenic responses.

The objectives of this study were to identify and quantify volatile compounds in beef that was dry aged or vacuum packaged and then oven roasted or microwave cooked. Supercritical CO 2 was used to extract the volatile compounds, and gas chromatography coupled with mass spectrometry or flame ionization detection was used for analyses. Classes of compounds isolated and identified included hydrocarbons (alkanes, alkenes, aromatic), alcohols, aldehydes, acids, ketones, esters, lactones, thiazoles, pyrazines, phenols, and furans. Differences in relative proportions of certain hydrocarbons, terpenoids, aldehydes, and ketones were observed for individual combinations of cooking×packaging interactions, some of which were directly attributed to autoxidation. Results indicate that quantifying single compounds was not sufficiently accurate. Instead, using total weight percentages of chemical classes was preferable