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Chromolaena sp. is believed to have phytochemical components namely alkaloids, flavonoids, flavone, essential oils, phenolics, saponins, tannins and terpenoids. In this study, ultrasound-assisted extraction (UAE) procedure was performed to extract the gallic acid extraction from the Chromolaena sp. UAE is known to be an environmentally green extraction method. The experiment was carried out with two different parameters which are sonication time and duty cycle. Phytochemical screening, High performance Liquid Chromatography (HPLC) and Fourier-transform infrared spectroscopy (FT-IR) was employed to determine the optimum condition for the extraction method. Phytochemical screening result showed the presence of phenolic compound when the dark-green colour of solution was observed. The optimum extraction conditions were as follows: sonication time of 80 minutes with yield of 3.0060 mg/mL and duty cycle of 10% with yield of 3.7641 mg/mL. The FT-IR result shows that presence of O-H and alkene group in the extraction sample. From the result, it can be concluded that UAE is an effective method to extract gallic acid from Chromolaena sp. The implication in this study were reducing the extraction time for the production of herbs medicine from natural resource like plant.

Conventional methods to remove heavy metals from polluted water are expensive and not environmentally friendly. Therefore, this study was carried out to investigate the potential of agricultural waste such as pineapple peel (Ananas Cosmos) as low-cost absorbent to remove heavy metals from synthetic polluted water. The results showed that Cd, Cr and Pb were effectively removed by the biosorbent at 12g of pineapple peels in 100 mL solution. The optimum contact time for maximum adsorption was found to be 90 minutes, while the optimum pH for the heavy metal’s adsorption was 9. It was demonstrated that with the increase of adsorbent dosage, the percent of heavy metals removal was also increased due to the increasing adsorption capacity of the adsorbent. In addition, Langmuir model show maximum adsorption capacity of Cd is 1.91 mg/g. As conclusions, our findings show that pineapple peel has potential to remove heavy metal from polluted water.

Labisa pumila var alata contains bioactive compounds such as gallic acid that is of use for pharmaceutical and nutraceutical industries. Aqueous extraction is the traditional method that extracts phytochemicals from plant material. The study aimed to find the optimum condition for maximum gallic acid yield from ground L. pumila leaves using aqueous extraction. The results revealed that the maxium gallic acid yield obtained was at 1:10 sample to water ratio for 8 h at 50 °C. The maximum yield of gallic acid obtained was 1.025 mg gallic acid per g dried leaves (mg/g). The identification of gallic acid was done on Liquid Chromatograph Mass Spectrometer Quadrupole Time-of-Flight (LCMS-Q-TOF) by comparison to that of reference standard. The morphological structure of the extract that was obtained at optimum condition showed less denaturation of cell wall which indicates that still some gallic acid could be trapped in the sample matrix and other methods need to be employed to release them.

Tongkat Ali is a well-known plant for its’ various bioactivities for human health. However, Tongkat Ali processing suffer from low yields and time consumption. Therefore, this study had been done to investigate the water soluble extracts (WSE) and water soluble proteins (WSP) in water extracts of Eurycoma apiculata that were obtained by microwave assisted extraction (MAE) to accomplish increases in the yields with high efficiency and less time consumption. The study was based on a circumscribed composite central design (CCCD) based on four factors, namely the radius of particle size (P), temperature (T), microwave power (W) and irradiation time (i). The CCCD was successful in identifying the optimal condition for E. apiculata extraction by MAE. Results illustrated that the optimum conditions for obtaining the maximum WSE yield (6.932 ± 1.002%) were (P: 0.0254 mm, T: 61 °C, W: 430 W and i: 19 min) while for the maximum yield of WSPs (15.853 ± 0.697%) were (P: 0.0254 mm, T: 46 °C, W: 270 W and i: 19 min). Kinetic investigations were based on the comparison the second order extraction rate, Peleg and the two site kinetic model for the WSPs. Results revealed that the best empirical models to represent the kinetic characteristics of extraction process were the second order extraction rate and Peleg models with an R2 = 0.9714. The capability of the two site kinetic model represent the extraction was enhanced by the insertion of the degradation factor (kD) which was illustrated by the increase of R2 from 0.9296 to 0.9997. The study concluded that the MAE process is a more efficient extraction process than the one-step conventional extraction method, therefore it was nominated for the upscaling of extracting proteins from E. apiculata roots in pilot and industrial scales.

The traditional ways of protein extraction is disadvantageous from both economic and environment perspective. In this study, ultrasonic assisted extraction, UAE technique was used for the first time for the optimization process of extracting proteins from Eurycoma longifolia roots. The experiments demonstrated the successful effect of applying eccentric agitation with UAE to provide a combination of agitation and sonication to extract the proteins in short extraction times. Central composite design (CCD) was used to optimize the Ultrasonic-assisted extraction of proteins from roots of Eurycoma longifolia by water. Response surface methodology (RSM) was employed to investigate the effects of five independent variables; particle sizes ( A ), extraction temperatures ( B ), agitation speeds ( C ), amplitude ( D ) and duty cycle ( E ). The second enhanced model ( Y 2 ) prevailed to be more efficient in protein recovery with optimum conditions of A : 0.022 ± 0.022 mm, B : 49 °C, C : 1314 rpm, D : 9 W and E : 63% UI : 2.94 W·cm −2 was 9.543 ± 0. 946%. High agitation speed didn’t only affect the solvent properties, the diffusion of the solutes from the particles, cooling the extraction temperature, but influenced the distribution of cavitation bubbles and their impact on the solid particles. UAE was found to minimize the extraction of the same amount by conventional extraction 7-fold times. The results obtained in this study have exposed the capability of ultrasonic assisted extraction, UAE technology in extraction of protein from E. longifolia roots. Further works are nevertheless required to provide deeper understanding of the mechanisms involved to facilitate the development of optimum system applicable to the industry.

The biosphere is polluted with metals due to burning of fossil fuels, pesticides, fertilizers, and mining. The metals interfere with soil conservations such as contaminating aqueous waste streams and groundwater, and the evidence of this has been recorded since 1900. Heavy metals also impact human health; therefore, the emancipation of the environment from these environmental pollutants is critical. Traditionally, techniques to remove these metals include soil washing, removal, and excavation. Metal-accumulating plants could be utilized to remove these metal pollutants which would be an alternative option that would simultaneously benefit commercially and at the same time clean the environment from these pollutants. Commercial application of pollutant metals includes biofortification, phytomining, phytoremediation, and intercropping. This review discusses about the metal-accumulating plants, mechanism of metal accumulation, enhancement of metal accumulation, potential commercial applications, research trends, and research progress to enhance the metal accumulation, benefits, and limitations of metal accumulators. The review identified that the metal accumulator plants only survive in low or medium polluted environments with heavy metals. Also, more research is required about metal accumulators in terms of genetics, breeding potential, agronomics, and the disease spectrum. Moreover, metal accumulators' ability to uptake metals need to be optimized by enhancing metal transportation, transformation, tolerance to toxicity, and volatilization in the plant. This review would benefit the industries and environment management authorities as it provides up-to-date research information about the metal accumulators, limitation of the technology, and what could be done to improve the metal enhancement in the future.

Pasteurella spp. are Gram-negative facultative bacteria that cause severe economic and animal losses. Pasteurella-based vaccines are the most promising solution for controlling Pasteurella spp. outbreaks. Remarkably, insufficient biomass cultivation (low cell viability and productivity) and lack of knowledge about the cultivation process have impacted the bulk production of animal vaccines. Bioprocess optimization in the shake flask and bioreactor is required to improve process efficiency while lowering production costs. However, its state of the art is limited in providing insights on its biomass upscaling, preventing a cost-effective vaccine with mass-produced bacteria from being developed. In general, in the optimum cultivation of Pasteurella spp., production factors such as pH (6.0–8.2), agitation speed (90–500 rpm), and temperature (35–40 °C) are used to improve production yield. Hence, this review discusses the production strategy of Pasteurella and Mannheimia species that can potentially be used in the vaccines for controlling pasteurellosis. The physicochemical factors related to operational parameter process conditions from a bioprocess engineering perspective that maximize yields with minimized production cost are also covered, with the expectation of facilitating the commercialization process.

The asymmetric biraphid pennate diatom Amphora copulata, isolated from tropical coastal waters (South China Sea, Malaysia), was cultured for renewable production of lipids (oils) in a medium comprised of inorganic nutrients dissolved in dilute palm oil mill effluent (POME). Optimal levels of nitrate, phosphate, and silicate were identified for maximizing the biomass concentration in batch cultures conducted at 25 ± 2 °C under an irradiance of 130 µmol m−2 s−1 with a 16 h/8 h light-dark cycle. The maximum lipid content in the biomass harvested after 15-days was 39.5 ± 4.5% by dry weight in a POME-based medium with optimal levels of nitrate, phosphate, and silicate. Under the optimized conditions the maximum dry mass concentration of the diatom was 660 mg L−1 on day 12, declining to ~650 mg L−1 on day 15. For the 15-day batch operation, the final average productivities of the biomass and the lipids were 43.3 ± 4.5 mg L−1 d−1 and 17.1 ± 0.3 mg L−1 d−1, respectively. The fatty acids in the diatom lipids were found to be (%, w/w of total lipids): palmitoleic acid (39.8%), palmitic acid (31.9%), myristic acid (6.8%), oleic acid (4.7%), stearic acid (4.5%), arachidonic acid (3.9%), eicosapentaenoic acid (3.6%), linoleic acid (2.5%), tetracosanoic acid (1.7%), and linolenic acid (0.6%).

Growth of mutant gdhA Pasteurella multocida B:2 was inhibited by the accumulation of a by-product, namely ammonium in the culture medium during fermentation. The removal of this by-product during the cultivation of mutant gdhA P. multocida B:2 in a 2 L stirred-tank bioreactor integrated with an internal column using cation-exchange adsorption resin for the improvement of cell viability was studied. Different types of bioreactor system (dispersed and internal) with resins were successfully used for ammonium removal at different agitation speeds. The cultivation in a bioreactor integrated with an internal column demonstrated a significant improvement in growth performance of mutant gdhA P. multocida B:2 (1.05 &times, 1011 cfu/mL), which was 1.6-fold and 8.4-fold as compared to cultivation with dispersed resin (7.2 &times, 1010 cfu/mL) and cultivation without resin (1.25 &times, 1010 cfu/mL), respectively. The accumulation of ammonium in culture medium without resin (801 mg/L) was 1.24-fold and 1.37-fold higher than culture with dispersed resin (642.50 mg/L) and culture in the bioreactor integrated with internal adsorption (586.50 mg/L), respectively. Results from this study demonstrated that cultivation in a bioreactor integrated with the internal adsorption column in order to remove ammonium could reduce the inhibitory effect of this by-product and improve the growth performance of mutant gdhA P. multocida B:2.

The effect of CO2 partial pressure on ethanol dry reforming was evaluated over 5%Ce-10%Co/Al2O3 catalyst at = PCO2 = 20-50 kPa, PC2H5OH = 20 kPa, reaction temperature of 973 K under atmospheric pressure. The catalyst was prepared by using impregnation method and tested in a fixed-bed reactor. X-ray diffraction measurements studied the formation of Co3O4, spinel CoAl2O4 and CeO2, phases on surface of 5%Ce-10%Co/Al2O3 catalyst. CeO2, CoO and Co3O4 oxides were obtained during temperature–programmed calcination. Ce-promoted 10%Co/Al2O3 catalyst possessed high BET surface area of 137.35 m2 g-1. C2H5OH and CO2 conversions was improved with increasing CO2 partial pressure from 20-50 kPa whilst the optimal selectivity of H2 and CO was achieved at 50 kPa.

Honey is an extract of floral and secretions from a variety of bees. Some honey manufactures adulterate pure honey with industrial sugar, chemicals, and water either directly or indirectly. Many methods have been developed to detect honey adulterants including physicochemical analysis, microscopy, chromatography, immunoassay, thixotropicity, DNA metabarcoding, sensors, and spectroscopy. However, the most promising methods for the development of a portable test kit for honey adulterant detection are ELISA, electronic tongue, and NIR. The most sensitive and accurate method is NIR. These methods have shown satisfactory results when used individually or combined. Further research is still required to trial different combinations of methods to improve accuracy and the ability to detecting a wide variety of adulterants simultaneously. There is a need to develop a portable honey adulterant detection method, such as NIR spectroscopy using a smartphone.

Ficus deltoidea or ‘mas cotek’ is among the well-known traditional herbal plants in Peninsular Malaysia that drawn much attention of growers worlwide because of their bioactive compounds used in reducing the risk of cancer, diabetes and heart diseases. Vitexin and isovitexin are two remarkable compounds of flavone C-glycosides found in the leaves extracts of Ficus deltoidea and chosen as biomarkers due to their abundant phytochemical and pharmacological activities. The conventional extraction methods have been used for decades. However, in this research, extraction of vitexin and isovitexin were improved by the implementation of microwave. Microwave-assisted hydrodistillation (MAHD) extraction can enhance the extraction efficiency by disrupting the plant cell wall, facilitate the solvent penetration into plant material and allow the intracellular product release by using microwave energy to heat solvents in contact with a sample and accelerate the mass transfer of target compounds from the sample matrix. The effect of main factors which were extraction temperature, irradiation time, microwave power and plant material to water ratio were investigated to obtain a maximum vitexin and isovitexin yield. As a result, the best condition that has been determined for highest vitexin and isovitexin production were under 70°C for 120 minutes at water to raw material ratio 1:10 using 500W power. This best condition of extraction of vitexin and isovitexin was finalized based on its highest yield obtained from the microwave which were 33.40 ± 0.98 (% w/w) with 1.152-fold and 11.38 ± 0.86 (% w/w) with 0.65-fold, respectively. The conventional aqueous extraction was used as a control throughout the whole processes. High performance liquid chromatography (HPLC) was used to analyse yield of vitexin and isovitexin in the extracts

Bioprocess characterizations are commonly evaluated to justify the use, setting alteration and future scaling-up. This paper discussed on some bioprocess characterization of 2-L sonobioreactor against the standard bioreactor (control). The objective of this study was to evaluate whether the additional and adjustment of a standard bioreactor into a sonobioreactor had a different bioprocesses characters. The bioreactor was set at four settings, 1) control, 2) control with flow rate, 3) flow rate with 10% duty cycle and 4) flow rate with 40% duty cycle. Accordingly, four simple characterizations were measured, power number, mixing time, response time, and volumetric mass coefficient. The results showed most of the characterizations were similar except for the mixing time. The control was found significantly faster than other settings at 10 s by a conductivity method. As a conclusion, findings explained the sonobioreactor settings affected the mixing time due to the use of flow rate and sonication

Central composite designs (CCDs) for UAE and WE were established by seven and five extraction factors, respectively, to determine their optimum conditions that maximized the saponins yields. These optimum conditions were employed successively to establish a sequential extraction (SE) of saponins from Eurycoma longifolia roots. Results identified the agitation speed as an influencing factor in altering the interactive effects of the extraction factors in UAE and WE. Optimized conditions illustrated that higher agitation speeds increased the yields of saponins in WE while UAE preferred lower agitation speed ranges. This implied that the high agitation speeds decreased the collision of microjets and particles and hence the the decrease of sonication efficiency. The SE extraction was proposed by initial sonication of the plant sample for a duration of 5 minutes and 29 seconds to 10 minutes followed by conventional WE for 20-25 minutes.

Industrial and sand mining activities have severely degraded the water quality of the Kelantan River, as well as the river ecosystem. However, there have been inadequate studies on the effect of industrial and sand mining on organisms in the Kelantan River. Therefore, this study assessed the concentrations of Pb, Cd, Zn and Cu in the bivalves of genus (Polymesoda expansa) marsh clams from the Kelantan River tributaries, namely the Geting River and the Semarak River, which are located near to an industrial and a sand mining area, respectively. More than 50 marsh clams were collected at these sites. Heavy metals in marsh clams were extracted using aqua regia methods and analyzed using a Flame Atomic Absorption Spectrometer (FAAS). The mean concentrations of Pb, Cd, Zn and Cu at the Semarak River were 4.61, 2.16, 194 and 6.20 mg/kg, respectively. Accordingly, the concentrations at the Geting River were 4.43, 2.50, 196 and 7.90 mg/kg, respectively. The pattern of metal concentrations within the whole tissue of marsh clams from the Geting River and the Semarak River were in the following order: Zn > Cu > Pb > Cd (concentration in mg/kg). The mean concentration of selected metals (Zn, Cd, Pb) in the studied samples exceeded the permissible limit set by the Malaysia Food Safety and Food Regulation 1985, the Food and Agricultural Organization, the World Health Organization, the Ministry of Health Thailand, and the Food and Drug Administration of United States (USFDA). Therefore, continuous monitoring of these bioindicators is essential to minimize the increasing health risk for aquatic life, as well as in food sources for human consumption, in the Kelantan River Basin. HIGHLIGHTS Heavy metals in Marsh Clam (Polymesoda expansa) tissues shows higher concentration in the small and medium sizes compare to big size The concentration of heavy metals (Zn, Cd and Pb) in Marsh Clam (Polymesoda expansa) tissues have exceeded the permissible limit set by Food and Drug Administration of United States (USFDA) and Malaysia Food Safety and Food Regulation Monitoring of heavy metals in aquatic organisms especially near to industrial and sand mining areas should be conducted regularly to reduce the risk to human health GRAPHICAL ABSTRACT

Continuous removal of ethanol during production by the anaerobic bacterium Zymomonas mobilis mitigated ethanol inhibition. Ethanol inhibited its own production at a concentration of >20 g L−1. Ethanol productivity was enhanced by continuous in situ extraction with water-immiscible organic solvents. Several solvents were evaluated for biocompatibility with Z. mobilis and the ability to extract ethanol from a batch fermentation. In situ batch extractive fermentations were carried out in a 2-L stirred bioreactor (1:1 volume ratio of solvent and fermentation broth) with an optimal glucose concentration of 150 g L−1, 35 °C, and an agitation speed of 150 rpm. Oleyl alcohol, iso-octadecanol and 2-octyl-1-dodecanol were the three solvents that were most compatible with Z. mobilis. With these solvents, the cell viability relative to control (no solvent) was 1.48 ± 0.40, 1.03 ± 0.18 and 1.05 ± 0.07, respectively, after two days of exposure. All solvents tested improved the final biomass concentration, the glucose consumption and ethanol production relative to control, but iso-octadecanol was clearly the most effective solvent. Using iso-octadecanol, the maximum ethanol concentration of 75 ± 3 g L−1 was attained. This was nearly 1.25-fold that of the control fermentation. For this solvent, the ethanol yield on glucose was 0.485 ± 0.005 g g−1 compared to a yield of 0.468 ± 0.005 g g−1 for the control culture.

Optimization of protein yields in water extracts that were obtained from Jackiopsis ornata roots by Microwave assisted extraction (MAE) was established by a Circumscribed Central Composite Design (CCCD). MAE proved to be an optimum choice for the protein extraction. The highest yield (20.425±108) was obtained with the parameters liquid to solid ratio (S= 30:1), particle size (P=0.022±0.002mm (radius), temperature (T= 65°C); microwave power (W= 300W) and extraction time (t= 20 minutes). Statistical analysis illustrated the adequacy of the generated full quadratic equation with ad high values of the coefficient of determination (R2), adjusted coefficient of determination R2adj and predicted coefficient p of determination R2pred The p value of the Lack of Fit test illustrated the adequacy of the model. The optimization conditions of extracting the protein was predicted to be with the parameters S: 26, P: 0.0284; T: 65 °C; P: 303 W and t: 20 min. The high efficiency of MAE to obtain J. ornata protein extract encouraged further application on pilot and industrial scale.

Pergau Dam as the largest hydroelectrical generation station in Peninsular Malaysia within a mountainous region; is supplied by many flowing river as its intakes. Previous researches within Pergau area mostly focused on biodiversity while this research was to carry out baseline investigation on the minerals present in the intakes sediment of Pergau Dam through surface sampling. Through stereoscopic observation, assemblages of quartz, plagioclase, feldspar, muscovite, and biotite minerals in sediments implies a granitoid source rock. By computing X-ray Fluorescence (XRF) chemical compositional data of sediments into chemical weathering indices, overall weathering condition of Pergau Dam intakes area are unweathered to low chemical weathering intensity. Through Combination of XRF data and X-ray Diffraction (XRD) patterns of mineral phases, detailed mineralogy of plagioclases, K-feldspars, sericites, chlorites and accessory minerals such as epidotes, zircon and monazite were identified. Mineral assemblage and Streckeisen Diagram plots indicate the granitoid source rocks of the sediments are quartz monzorite and quartz monzodiorite.

Amperometric biosensor for glucose content measurement in Malaysian stingless bee honey was developed using screen printed carbon electrode (SPCE) integrated with paper disc immobilized with enzyme Glucose Oxidase (GOx) using simple physical adsorption method. The paper-based biosensor required only 8 μL of sample solution for glucose analysis. The calibration of glucose biosensor is linear between 0.5 mM to 4.5 mM (R2= 0.9925) and has a detection limit of 0.15 mM. Interference study on several compound affecting the biosensor response and storage stability was investigated. In addition, its performance was demonstrated in the analysis of six honey samples. The results obtained using glucose biosensor was validated by high performance liquid chromatographic (HPLC) method. The addition of glucose in pure honey at various concentration were also tested by this paper-based biosensor where the current obtained shows increasing trend with the addition of glucose. From this research, it can be concluded that, the prototype sensor to determine glucose adulteration in stingless bee honey was successfully developed.

Even though Eurycoma longifolia was extensively studied, few researches investigated the protein content in its water extracts with the consideration of establishing the most suitable extraction method to increase their yields with high efficiency and less time consumption. The study applied a sequential extraction method to increase the yields of water soluble proteins (WSPs) in E. longifolia root extracts by the application of two nonconventional extraction methods, Microwave assisted extraction (MAE) and ultrasound assisted extraction (UAE). The study was established by circumscribed central composite designs (CCCDs) to indicate the optimum extraction conditions and the corresponding maximum WSPs yields for both the methods by investigating the MAE factors which were temperature (T); microwave power (W) and irradiation time (i) and UAE factors temperature (T); ultrasonic intensity (UI); and sonication time (s). The optimum conditions of MAE (T: 54°C, W: 301W and i: 15 min) led to the WSPs yield 23.101±1.647%.The optimum conditions of UAE (T: 46°C; UI: 1.84 W.cm”2 and s: 24 min) led to 24.181±0.321%. These predicted optimum conditions were then employed for the two proposed sequential extraction method, sequential ultrasound-microwave assisted extraction (SUMAE) and sequential microwave-ultrasound assisted extraction (SMUAE). Results revealed that the highest WSPs yield (27.172±1.086%) was obtained by initiating the sequential extraction with UAE for 10 minutes followed by MAE treatment for 5 minutes was the best extraction process. Therefore, SUMAE illustrated more efficiency than SMUAE. This concluded that the SUMAE is a more efficient extraction process than the one-step nonconventional extraction methods and was nominated for the upscaling of extracting proteins from E. longifolia roots in pilot and industrial scales.

Commercial honey is widely available in the market, raising questions whether the honeys are good in quality or otherwise, Thus, this research was designed to compare the quality of harvested stingless bee honey and commercial honey available in the Malaysian market by measuring their sugar profile and enzyme activity. The analysis showed that the honey contained moisture between 16.6% - 32.1%, various sugar starting with fructose (15.03 – 48.44 g/100 g), glucose (12.16 – 40.09 g/100 g), sucrose (H. Itama and G.Thoracica showing comparable results with past studies and within the limits of Malaysian Standard. However, all honey samples demonstrate lower enzyme activity suggesting that honey from stingless bee has low enzyme activity compare to Apis mellifera honey.

Persian Abstract: تاثیر فشار جزئی کاربن دای اکساید در ریفورمینگ ایتانول به طریقه خشک باالی کتلست Al2O3/Co%10-Ce%5 در فشار های گاز کاربن دای اکساید از 20 الی 50 کیلو پاسکال، فشار ایتانول 20 کیلوپاسکال، حرارت 973 درجه کلوین وتحت فشار اتمسفیری ارزیابی گردیده است. کتلست بطریقه اشباع سازی مرطوب آماده گردیده و در دستگاه با بستر ثابت امتحان شده است. فاز های اکساید کوبالت Co3O4 ،اسپینل اکساید CoAl2O4 و اکساید سیریم CeO2با استفاده از انالیز XRD در سطح کتلست تشکیل شده است. اکساید های سیریم و کوبالت درجریان پروگرام حرارتی کلسینه g 1 -شدن بدست آمده است. کتلست Al2O3/Co%10-Ce%5 دارای مساحت سطح بلند 2 m 35.137 میباشد. ایتانول و کاربن دای اکساید تبدیل شده با افزایش فشار جزئی گاز کاربن دای اکساید از 20 الی 50 کیلو پاسکال، افزایش نموده درحالیکه مقدار مطلوب محصول هایدروجن و کاربن مونواکساید در فشار 50 کیلو پاسکال بدست آمده است. English Abstract: The effect of CO2 partial pressure on ethanol dry reforming was evaluated over 5%Ce-10%Co/Al2O3 catalyst at = PCO2 = 20-50 kPa, PC2H5OH = 20 kPa, reaction temperature of 973 K under atmospheric pressure. The catalyst was prepared by using impregnation method and tested in a fixed-bed reactor. X-ray diffraction measurements studied the formation of Co3O4, spinel CoAl2O4 and CeO2, phases on surface of 5%Ce-10%Co/Al2O3 catalyst. CeO2, CoO and Co3O4 oxides were obtained during temperature–programmed calcination. Ce-promoted 10%Co/Al2O3 catalyst possessed high BET surface area of 137.35 m2 g-1. C2H5OH and CO2 conversions was improved with increasing CO2 partial pressure from 20-50 kPa whilst the optimal selectivity of H2 and CO was achieved at 50 kPa.

This study aimed to investigate the structural features of the isolated flavonol glycoside, which might behave as a cytotoxic compound. The hexane, chloroform, ethyl acetate, and aqueous fractions of an 80% methanol solution of Neem (Azadirachta indica) (Family: Meliaceae) leaves were subjected to a cytotoxicity bioassay against brine shrimp, Artemia salina. The ethyl acetate fraction exhibited the highest cytotoxic effect, supported by the lowest lethal concentration, a LC50 value of 1.35±0.40 ppm. A compound, Quercetin 3-O-β-D-glucopyranoside, was isolated from the most toxic fraction of the ethyl acetate via preparative liquid chromatography and then identified via ultraviolet-visible (UV-Vis), infrared (IR), mass spectrum (MS) and nuclear magnetic resonance (NMR) analyses. The compound was further confirmed by physical state, color, solubility, and melting point determination. The cytotoxic results suggest that the leaf ethyl acetate fraction consists of toxic compounds, which point towards the isolation of Quercetin 3-O-β-D-glucopyranoside.

Excess molar volume and viscosities are one of the important fundamental data for the design and optimization of chemical process. In this study, excess molar volume and viscosities of 1,4 Dioxane with two hydrocarbons Bromobenzene and Ethyl benzene have been measured over the entire range of composition at (303.15, 308.15, and 313.15) K. From experimentations excess volumes, VE, and deviations in viscosities, Δη, are calculated. The calculated excess volumes, VE and deviations in viscosities, Δη exhibited positive and negative values respectively over the whole range of composition in both binary systems. The Redlich-Kister Model was used to correlate excess volumes, VE, and deviations in viscosities, Δη, to derive the binary coefficients and standard deviations of these systems. The fitted outcomes and the calculated data clearly indicated that weak interactions present in two mixtures. It is mainly because of number and position of methyl groups exist in these aromatic hydrocarbons. It can conclude that the experimental values are predicted well by the Redlich-Kister Model with high degree of precision.

The growing demand for honey in the market has led to the occurrence of the tampering honey with foreign substances and increases the production of artificial honey. Due to this concern, this study works on the physicochemical and microbial characterization of stingless bee honey. The physicochemical analysis showed that the honey possessed pH (2.51–3.26), free acidity (121.1 to 318.7 meq/kg), moisture (19.4–30.9%), electrical conductivity (0.33–0.69 mS/cm), ash content (2.75–4.31 g/100g), Hydroxymethylfurfural (HMF) content (35.4 to 461.7 mg/kg) and diastase activity (2.71 to 6.11 DN). Also, sugar profile of honey showed that the honey contained fructose (15.03–32.52 g/100g), glucose (12.17–34.55 g/100g) and sucrose (0.01–7.29 g/100g). The harvested honey, H1, and H2 have the highest potential to become an antibacterial agent to treat disease compared to commercial honey samples because they were active against Gram-negative bacteria. All analyzed samples were within the maximum limit of the quality criteria set by the Malaysian Kelulut Standard and Codex Alimentarius except for free acidity, HMF, and Diastase Number. All the data obtained is vital in order to create a specific statute for stingless bees honey in Malaysia that may help to protect the consumer from purchasing adulterated honey.

Production of ethanol from lactose by fermentation with the yeast Kluyveromyces marxianus (ATCC 46537) under various sonication regimens is reported. Batch fermentations were carried out at low-intensity sonication (11.8 W cm −2 sonication intensity at the sonotrode tip) using 10%, 20% and 40% duty cycles. (A duty cycle of 10%, for example, was equivalent to sonication for 1 s followed by a rest period (no sonication) of 10 s.) Fermentations were carried out in a 7.5 L (3 L working volume) stirred bioreactor. The sonotrode was mounted in an external chamber and the fermentation broth was continuously recirculated between the bioreactor and the sonication chamber. The flow rate through the sonication loop was 0.2 L min −1 . All duty cycles tested improved ethanol production relative to control (no sonication). A 20% duty cycle appeared to be optimal. With this cycle, a final ethanol concentration of 5.20 ± 0.68 g L −1 was obtained, or nearly 3.5-fold that of the control fermentation. Sonication at 10% and 20% cycles appeared to stimulate yeast growth compared to the control fermentation, but 40% duty cycle had a measureable adverse impact on cell growth. Sonication at 10% and 20% cycles enhanced both the extracellular and the intracellular levels of β-galactosidase enzyme. Although at the highest duty cycle sonication reduced cell growth, cell viability remained at ≥70% during most of the fermentation. Sonication at a controlled temperature can be used to substantially enhance productivity of bioethanol fermentations.

Activated sludge models (ASMs) have been widely used as a basis for further model development in wastewater treatment processes. Values for parameters to be used are vital for the accuracy of the modeling approach. A continuous stirred tank reactor (CSTR), as open respirometer with continuous flow for 20 h is used in ASMs. The dissolved oxygen (DO) profile for 11 days was monitored. It was found the mass transfer coefficient K(La) is 0.3 h(-1) during lag and start feed phase and 0.01 h(-1) during stop feed phase, while the heterotrophic yield coefficient Y(H) is 0.44. Some of the chemical oxygen demand (COD) fractionations of palm oil mill effluent (POME) using respirometric test in ASM models are S(s) 50 mg/L, S(I) 16,600 mg/L, X(S) 25,550 mg/L, and X(I) 2,800 mg/L. The comparison of experimental and ASM1 from OUR concentration is found to fit well.

A full factorial design (FFD) approach was conducted to assess the effect of four factors, namely flow rate, duty cycle, amplitude, and treatment time of ultrasonic regimens towards Escherichia coli harbouring lipase. The 22 experiments were performed as the following values with six replicates of centre point: flow rate (0.1, 0.2, and 0.3 L/min), duty cycle (0, 20, and 40 ), amplitude (2, 6, and 10), and treatment time (10, 35, and 60 min). The FFD was employed as preliminary screening in shake flask cultivation to choose the significant factors (P< 0.05) for further optimisation process. In this study, zero duty cycle signified non-sonication of amplitude and no treatment time effect to the E. coli culture. Also, the designated flow rate and amplitude accordingly showed no effect towards the amount of dry cells weight (DCW). DCW1 was found significantly degraded after the exposure of high duty cycle and treatment time as other factors remained constant. Whereas for the lipase activity, no significant difference was observed in any main factors or interactions. Paired samples t-test confirms the result at a p-value of 0.625. This experimental study suggests the direct and continuous approach of sonication caused an adverse effect on the cells culture density.

A recombinant Trichoderma reesei cellulase was used for the ultrasound-mediated hydrolysis of soluble carboxymethyl cellulose (CMC) and insoluble cellulose of various particle sizes. The hydrolysis was carried out at low intensity sonication (2.4-11.8 W cm(-2) sonication power at the tip of the sonotrode) using 10, 20, and 40% duty cycles. [A duty cycle of 10%, for example, was obtained by sonicating for 1 s followed by a rest period (no sonication) of 9 s.] The reaction pH and temperature were always 4.8 and 50°C, respectively. In all cases, sonication enhanced the rate of hydrolysis relative to nonsonicated controls. The hydrolysis of CMC was characterized by Michaelis-Menten kinetics. The Michaelis-Menten parameter of the maximum reaction rate Vmax was enhanced by sonication relative to controls, but the value of the saturation constant Km was reduced. The optimal sonication conditions were found to be a 10% duty cycle and a power intensity of 11.8 W cm(-2) . Under these conditions, the maximum rate of hydrolysis of soluble CMC was nearly double relative to control. In the hydrolysis of cellulose, an increasing particle size reduced the rate of hydrolysis. At any fixed particle size, sonication at a 10% duty cycle and 11.8 W cm(-2) power intensity improved the rate of hydrolysis relative to control. Under the above mentioned optimal sonication conditions, the enzyme lost about 20% of its initial activity in 20 min. Sonication was useful in accelerating the enzyme catalyzed saccharification of cellulose.