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Supercritical carbon dioxide (ScCO2) extraction assisted by Ethanol is one of the development methods to extract polar and nonpolar compounds. Thus, the objective of the study was to optimize extraction parameters to recover total phenolic content (TPC) and total flavonoid content (TFC) from peanut skin. Chrastil, Del Valle Aguilera, and Adachi-Lu models were applied to determine the solubility behaviors. The optimum condition was found at 29.43 MPa, 319.16 K, and 0.09 ml/min with 290.12 mg/L TPC and 488.26 mg/L TFC. Chrastil model gives good agreement to fit the solubility of flavonoid and phenolic contents due to the lowest Average absolute relative deviation were 3.27% and 7.75%, respectively. Practical applications: Peanut skin as waste of peanut industries contains high phenolic and flavonoid contents. Currently, conventional extraction process with toxic solvent has been used to extract peanut skin. ScCO2extraction is one of the solutions to break the limitation of solvent's toxicity. However, ScCO2 has the drawbacks that ScCO2 is powerful to extract the nonpolar compounds, but failure to extract the medium polar compounds especially for the flavonoid compounds. Thus, the addition of ethanol is one of development method to break this limitation. Furthermore, Semi-empirical model has been used in this study to determine the solubility behavior to enhance the solubility of phenolic and flavonoid contents. The results show that high temperature condition is suitable to enhance the solubility of TPC, otherwise low temperature condition is preferable in the enhancement of TFC solubility.

Propolis is a resinous substance produced by bees functioned to seal holes, exclude draught, protect against contamination and external intruders inside their hives has been substantially studied and reported to have numerous health properties such as antiseptic, antifungal, antibacterial, antiviral, anti-inflammatory and antioxidant characteristics. Propolis cannot be utilized as raw material, due to its complex mixture of compounds. Hence it must be separated by the extraction process. Extraction targets to removes the inert compounds in the propolis sample and preserves the flavonoids and polyphenolic fraction. The most common technique used in propolis extraction is solvent extraction that involves the use of solvents such as ethanol, water, hexane, ethyl-acetate and chloroform. However, this conventional technique has some drawbacks including strong residual flavour, possible adverse reactions, harmful to the environment, low quality of the extract and long process period requirement. Supercritical carbon dioxide (SC-CO2) is one of the alternative techniques to conventional extraction that was reported to be an excellent method to purify and fractionate bioactive compounds from natural sources. SC-CO2 extraction was first introduced for analytical application because of the demand to reduce organic solvent utilization in a laboratory environment. It has now become a favourite technique in extraction, fractionation, refinement, and deodorization of natural sample matrices in laboratory scale and industrial scale. Carbon dioxide is an ideal supercritical solvent due to its non-toxic, non-polluting, non-flammable, recoverable and environmentally benign properties. Therefore, this mini review aims to discuss the application of supercritical carbon dioxide extraction specifically on propolis sample starting with a brief introduction on propolis, methods of propolis extraction, the principle of SC-CO2 extraction, application of SC-CO2 in propolis extraction, advantages of SC-CO2 extraction and lastly comparison between SC-CO2 and conventional extraction techniques.

Charantin extract from Momordica Charantia fruits for anti-diabetic compound was proposed via Supercritical Fluid Extraction using carbon dioxide (SC-CO2) as solvent. This method is a promising alternative technique to a conventional Soxhlet and shaking water bath extraction method. Experiments were conducted to analyze the charantin i) with and without modifier (ethanol), ii) Soxhlet extraction with four types of solvent (distilled water, ethanol, dichloromethane, and petroleum ether) and iii) shaking water bath with distilled water as a solvent. A purification step was conducted post extraction to remove intrusive components such as chlorophylls and sugar from analyte in order to quantify charantin extract using high performance liquid chromatography (HPLC). The results show that, in 2.5 hours SC-CO2 with ethanol as modifier gives highest charantin yield with 0.7817 mg charantin per gram sample. In contrast, shaking water bath gives the highest charantin yield for conventional method with 0.712 mg charantin per gram sample during 6 hours of extraction. The result shows that by using SC-CO2 modified with ethanol can be a promising “green” extraction than conventional method.

The issues involved with conventional lipid extraction methods, such as the usage of toxic solvents and accumulation of chemical waste, has motivated researchers to find an alternative approach to the extraction technology. One of the alternatives is via the Supercritical Carbon Dioxide (SC-CO2) method. This extraction method is considered as green as it provides a clean, selective and efficient process. Although the SC-CO2 method has been successfully used to extract lipids from microalgae, there are still some issues related to sample preparation and process parameters that need to be resolved. Therefore, this study investigates the effect of adding a modifier (ethanol) and using different types of holders (cotton and steam bun cloth) has on the yield of lipid from Nannochloropsis salina. The usage of a holder is required during the process due to the fine particles of the microalgae which have the potential to clog the instrument used. The SC-CO2 extraction without the modifier was conducted for 4 hours at 60°C, 30 MPa and CO2 flow rate of 4 ml/min, while the extraction with the modifier was conducted using 3.8 ml/min CO2 and 0.2 ml/min ethanol. It was found that the highest lipid yield of 0.16 g lipid / g dried microalgae was achieved using cotton cloth as a holder with the addition of the modifier. Lower amount of lipids were obtained when using the Soxhlet method (0.08 g lipid / g dried microalgae) and SC-CO2 without modification (0.02 g lipid / g dried microalgae). These preliminary findings show that the SC-CO2 process requires modifications to enhance the lipids yield from microalgae.

Supercritical carbon dioxide (SC-CO 2 ) is a fluid with high diffusivity and low viscosity which can penetrate deep into the solid particle efficiently compared to liquid or gas. SC-CO 2 commonly used as a green solvent in the modern extraction of bioactive compound from plants. Sometimes, a co-solvent was added in the system to increase solvent polarity or mix a co-extractant with dried sample to improve solute’s transport properties. Hence, the aim of this study was to determine Momordica charantia extract yield with different mean particle size as well as diffusion coefficient, D e in the extraction process with and without co-extractant. Different mean particle sizes used were 0.2, 0.3, 0.5 and 0.7 mm at constant operating condition (20 MPa, 65 o C and 4 mL/min). A ratio 1:3 of pure ethanol was used in the extraction process with co-extractant. Based on the results, mean particle size of 0.3 mm gave the highest extract yield, 3.32% and 1.34% with and without co-extractant respectively. Whereas, the value of D e at 0.3 mm mean particle size, with and without co-extractant are 8.820 x 10 -12 and 7.920 x 10 -12 m 2 /s respectively. Therefore, 0.3 mm is the best mean particle size to produce highest Momordica charantia extract yield and D e value in SC-CO 2 extraction with co-extractant.

Supercritical fluid extraction is an advanced extraction technique that suitable for heat sensitive and active compound material from plants and herbs. Understanding the effect of extraction parameters on mass transfer coefficient at solid and fluid phase can determine the dominating extraction regime thus performance of the extraction may be enhanced. The aim of this research was to determine the mass transfer coefficient in solid and fluid phase using kinetic modelling approach. Grounded betel nuts were treated with supercritical carbon dioxide with 5% methanol as co-solvent to determine its mass transfer coefficient in solid and fluid phase for the following extraction conditions; pressure, 20 to 30 MPa; temperature, 50 to 70 °C; and flow rate, 2 to 4 mL/min. Simplified Sovova model was coupled with Broken and Intact Cell model to determine the mass transfer coefficients. Results show the mass transfer coefficients of solid phase and liquid phase are in the ranges of 0.00015 to 0.00353 m3/min and 0.3497 to 3.9623 m3/min, respectively. The overall absolute average relative deviation was observed to be 7.39%.

Peanut skin is a waste by-product from peanut industries. It is rich in antioxidants and bioactive compounds. Therefore, the objective of this study was to empirically model and optimize su...

Todays, medicinal plants have been of great importance to the health of people and societies in Malaysia, and the entire world. Piper betle leaves, a member of family Piperaceae is an edible plant. The leaves of Piper betle have been traditionally utilized in India for inhibition of oral diseases. Scientific research shows that the leaves possess many biological activities with a good medicinal and commercial value. Nowadays, advance technologies have been used to develop high quality products. This study concentrates on supercritical fluid extraction technology which carbon dioxide, CO 2 play as a solvent. The purpose of this study was to optimize and look into the effects of supercritical CO 2 (SC-CO2) extraction process variables, namely pressure (10–30 MPa), temperature (40–80 °C) and CO 2 flowrate (2-8 mL/min) on global oil yield and percentage of Eugenol in Piper betle Leaves. The result shows that as the pressure, temperature and flow rate of CO 2 increased the oil yield of Piper betle leaves increased. However, further increased, resulting in decreasing the amount of global oil yield. Meanwhile, the percentage of Eugenol increased as the CO 2 flow rate increased. However, as the pressure and temperature increased, the percentage of Eugenol decreased. Second order polynomial model was used to express the extracted oil and percentage of Eugenol with the both results was satisfactory. The best conditions to maximize the global oil yields and percentage of Eugenol extracted were 19.0 MPa, 40.0 °C and 7.0 mL/min leading to 0.228g of oil and 8.21 % of Eugenol. The most dominant factor for both responses was CO 2 flowrate. The results show a good fit to the proposed model and the optimal conditions obtained were within the experimental range with the value of R 2 was 69.06% for global oil yield and 82.79% for amount of Eugenol.

In this work, the effect of extraction parameters on catechin extraction from betel nuts was studied. The supercritical carbon dioxide extraction parameters were pressure, temperature, and solvent flow rate while using average particle size of 177.5 μm and 5% (v/v) methanol as modifiers. Detection and quantification of catechin were achieved using HPLC analysis. The highest amount of extract and catechin concentration were 34.00 mg extract/g sample and 565.38 ppm of catechin obtained at 30 MPa, 70°C, and 4 mL/min. The results given by optimization tools suggest the same operating conditions with less than 3% difference.

The present work was aimed to evaluate the removal of methyl violet dye by potassium hydroxide-treated palm kernel shell sorbents. The sorbents were prepared by dried impregnation, carbonization and chemical activation in a muffle furnace. The sorbents were characterized for specific surface area, surface morphology and functional groups. Results show that the activated carbon displayed a specific surface area of 302 m2/g, which was 54 times greater than the impregnated sorbent. However, the latter showed a 42 mg/g maximum adsorption capacity of methyl violet, nearly four times better than the former. The equilibrium data were fitted well with the Langmuir isotherm, while the rate of sorption data obeyed the pseudo-second-order model. Adsorption of methyl violet was not specific surface area-dependent. The rate-limiting step for methyl violet adsorption was mainly driven by film diffusion at lower concentration, and intraparticle diffusion at higher concentration. A simple impregnation using potassium hydroxide was a promising approach to yield sorbent rich in acidic groups for methyl violet removal.

The objective of this work is to evaluate the removal of methylene blue dye by bio-polishing sludge-based adsorbents. The adsorbents were characterized according to the specific surface area, pH upon the treatment and surface functional groups. The adsorption of dye was carried out at room temperature, and the adsorption data were analyzed using the isotherm and kinetics models. The bio-polishing sludge is rich in ash content, and the presence of surface functional groups varied with the treatment strategies. The specific surface area of adsorbents is between 7.25 and 20.8 m2/g. Results show that the maximum removal of methylene blue by sludge adsorbents was observed to have the following order: untreated sludge (SR) > zinc chloride-treated (SZ) > microwave-dried (SW) = potassium carbonate-treated (SK) > acid-washed (SH). The maximum adsorption capacities for SR and SZ as predicted by the Langmuir model are 170 and 135 mg/g, respectively. Although SR demonstrates a higher maximum removal than SZ, the latter exhibits greater removal intensity and rate constant even at high dye concentration. The bio-polishing sludge is a promising adsorbent for dye wastewater treatment.

Hot compressed water extraction (HCWE) is a promising alternative technology which has proven to be successful in many applications. In this study, hot compressed water extraction (HCWE) was applied in the extraction of crude palm oil (CPO) from palm mesocarp. The operating conditions investigated were pressure of 30, 40 and 50 bar with varied temperature ranging from 120 to 180 °C through semi-batch extraction of 10 min interval and total extraction time of 60 min. The CPO yield, free fatty acids (FFA) content through HCWE process was analysed. Scanning electron microscopy (SEM) study on various palm mesocarp fibres undergone HCWE process at various conditions was also performed. The extracts formed three distinguished layers; oil, oil-water emulsion and water. The maximum CPO extracted in the oil layer was 0.541 ± 0.005 (g-oil/g-dried mesocarp) with averaged FFA of 0.81 ± 0.08% at the optimum operating condition of 160 °C and 50 bar. CPO recovered from the emulsion was 0.159 ± 0.004 g-oil/g-dried mesocarp giving a total CPO extracted at 0.700 ± 0.005 g-oil/g-dried mesocarp. SEM micrographs were used to assist understanding of the mechanism that took place during the experimental conditions of HCWE. The time dependence of the compounds was well represented by the second order mass transfer model. The mechanism of CPO extraction from palm mesocarp using HCWE was also explained through this study.

An optimization of coagulation and flocculation of kaolin suspension by a newly synthesized quaternized oil palm empty fruit bunch cellulose denoted as a 9QC was investigated using the central composite design of the response surface methodology. The influences of coag-flocculant dosage, pH, and kaolin suspension on turbidity removal efficiency and sludge volume index responses were studied and assessed according to a 23 full factorial design. The developed quadratic models revealed that the overall optimum values to obtain the highest performance of the responses were 62.5 mg/L of coag-flocculant dosage, pH 7, and 1400 mg/L of kaolin concentration. The predicted optimum responses were found to be in close proximity to the observed responses. The coag-flocculating of river water using 9QC carried out at the optimum values showed encouraging results as compared to alum which is commonly used in drinking water treatment process.

The potential use of lignocellulosic biomass as oil sorbents was demonstrated through acetylation of mercerized pineapple leaves (M-PAL) using acetic anhydride with catalysts ( N -bromosuccinimide and pyridine) in order to enhance its surface hydrophobicity and thus oil sorption capacity for treatment of dissolved oil contaminated wastewaters. The raw and acetylated PAL sorbents, before and after oil sorption, were characterized by a scanning electron microscope (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The oil sorption experiment was evaluated in batch sorption mode using dissolved o/w solution prepared by mixing crude oil and double-distilled water. It was found that the M-NBS-PAL sorbent yielded better oil sorption performance than R-PAL sorbent due to the replacement of hydroxyl group which has more hydrophobic acetyl group on the PAL surfaces, with strong affinity towards oil. The batch equilibrium data were fitted well by Langmuir isotherm model with the maximum sorption capacity ( q m ) of 37.45 and 90.91 mg/g for the R-PAL and M-NBS-PAL sorbents, respectively. The oil sorption process was thermodynamically feasible and exothermic, while the nature of interaction could be described via the physisorption mechanism. The kinetic sorption data were found to be fitted well into the pseudo-second order kinetic model. The sorption–desorption cycle was repeated four times whereby isopropanol was used as a desorbing agent and the results were comparable with freshly prepared sorbent. Finally, the present findings indicate that the lignocellulosic biomass could be a potential alternative as sorbent precursors for oil removal from oil contaminated wastewaters.

This work aims to evaluate the effects of different particle size, flow rate and modifier ratio on the extraction yield and anthocyanins content of Hibiscus sabdariffa L (Roselle) by using supercritical carbon dioxide (SC-CO2) method. SC-CO2 extraction was carried out at constant pressure and temperature, 10MPa and 70°C respectively with 75% (v/v) ethanol as a modifier. The result shows that 120 minutes was the efficient extraction time at a determination of flow rate. The trend and results for the extraction yield and anthocyanins were varied in all parameters studied. The finding shows that a low flow rate (4 ml/min), smaller particle size (200-355 µm) and high percentage ratio of modifier (10%) could obtain more anthocyanins content. Thus, the manipulation of several parameters in the SC-CO2 extraction process could enhance the selectivity of anthocyanins extraction from the total extract.

Well-designed montmorillonite (Mt) coupled graphitic carbon nitride (m-CN) composite for stimulating photocatalytic CO2 hydrogenation with H2 and H2O reducing agents has been investigated. 2D Mt nanosheets were uniformly anchored with 2D m-CN nanosheets for improving charge carrier separation. The photoactivity of 2D/2D Mt/m-CN was tested for CO2 photoreduction with H2O/H2 to CO/CH4 through RWGS and CO2 methanation reactions under visible light. Using 20% Mt/m-CN, highest CO and CH4 yield rate of 253 and 165 μmol g-cat−1h−1 were obtained, 5.9 and 6.4 times high than g-C3N4, respectively. This improved activity reflects synergistic effect between Mt and m-CN, which promotes photo-induced charge carrier separation. More interestingly, during CO2 reduction with hydrogen, CH4 was the main product and its production was 2.1 folds higher than using CO2 reduction by H2O. This selective CO2 hydrogenation to methane was obviously due to single-step CO2 methanation process with proficient H2 oxidation over highly efficient Mt/m-CN composite. The QY for CH4 production of 4.55% was obtained with high stability in cycles over the composite catalyst. The findings from this research would be fruitful for further investigation in CO2 conversion for selective fuels production to provide clean energy.

The aim of this work is to convert agroforestry residue to a novel adsorbent (M-1CTA-SDS-BT) used for adsorptive benzene sequestration from aqueous solution. In this study, the anionic surfactant-coated-cationized banana trunk was synthesized and characterized for batch adsorption of benzene from aqueous solution. The surface morphology, surface chemistry, surface area, and pore properties of the synthesized adsorbents were examined. It was proven that surface cationization successfully increased the benzene adsorption capacity of sodium dodecyl sulfate-coated adsorbents. The Langmuir isotherm model satisfactorily described the equilibrium adsorption data. The maximum benzene adsorption capacity (qmax) of 468.19 μmol/g was attained. The kinetic data followed the pseudo-second-order kinetic model in which the rate-limiting step was proven to be the film diffusion. The batch-adsorbent regeneration results indicated that the M-1CTA-SDS-BT could withstand at least five adsorption/desorption cycles without drastic adsorption capacity reduction. The findings demonstrated the adsorptive potential of agroforestry-based adsorbent as a natural and cheap material for benzene removal from contaminated water.

Hot compressed water extraction (HCWE) is a promising green alternative to the screw press in the palm oil processing. In this study, the steady-state characteristic of the HCWE was modeled by using an artificial neural network (ANN). The overall oil yield and other outputs; β-carotene, α-tocopherol and α-tocotrienol concentration, were described by the pressure and temperature in the HCWE. The results show that the predicted yield and concentrations agree well with experimental data. These models were used to estimate the optimum conditions of the HCWE process.

The aim of the present work is to determine the solubility of castor oil by using supercritical carbon dioxide as extracting solvent. A simple dynamic technique was used to obtain the solubility of castor oil in supercritical carbon dioxide. The solubility was measured at temperatures ranging from 313 to 335 K and pressures from 20 to 36 MPa. Under extraction conditions, the measured solubilities were in the range from 1.29 × 10 −3 to 4.88 × 10 −3 (g of oil)/(g of CO 2 ). Measurements confirmed that temperature and pressure have direct effects on solubility-enhancement factors. Five semi-empirical models were tested for their ability to correlate experimental data: the Chrastil, Del Valle Aguilera (VA), Bartle, Kumar and Johnston (KJ), and Mendez-Santiago and Teja (MST) models. Over the temperature and pressure ranges studied, solubilities from these models had the following average absolute relative deviations from experimental data: Chrastil, VA, Bartle, KJ and MST models with an average absolute relative deviation percent (AARD%) of 0.05%, 0.30%, 0.38%, 5.98% and 28.4%, respectively. Thus, the Chrastil, VA and Bartle models correlated the castor oil solubility data with the lowest AARD%.

The optimal conditions of oil yield from castor (Ricinus communis L) seed using supercritical CO2 as extracting solvent were studied. Response surface methodology (RSM) was employed to show explicitly the influence of the process parameters such as temperature, pressure and the CO2 flow rate on the oil yield using Box–Behnken design. The linear terms of pressure, CO2 flow rate and temperature and the quadratic terms of temperature, pressure and CO2 flow rate, had a significant effect on the oil yield. The maximum oil yield obtained from the mathematical model was predicted to be 9.29% under the conditions of temperature 63.72 °C and pressure 29.90 MPa with CO2 flow rate of 4.15 mL/min. The fatty acid constituents of the seed oil extracted using supercritical CO2 were determined by gas chromatography–mass spectrometry (GC–MS) and Fourier transform infrared spectrometer (FTIR). Palmitic, stearic, oleic, linoleic, linolenic and ricinoleic acids were identified by GC–MS analysis after the formation of fatty acid methyl ester (FAME).

Knowledge concerning the solubility of ginger bioactive compounds in hot compressed water (HCW) is important for designing an extraction process with water as a green solvent. The solubilities of 6-gingerol and 6-shogaol in hot compressed water are calculated using the conductor-like screening model for real solvent (COSMO-RS) method to study the potential of water as a solvent. The comparison indicates that the calculated solubility is at a higher concentration for the binary system of 6-gingerol + water and 6-shogaol + water when compared to the HCW extraction. This illustrates the performance of the HCW extraction, which has not reached the equilibrium condition, and gives an opportunity to explore the options for further improving the process. The availability as well as the thermo-labile nature of the bioactive compounds are factors that must be considered for the improvement of HCW as a solvent. The solubilities of 6-gingerol and 6-shogaol in aqueous ethanol solutions are also calculated by the COSMO-RS method to study the entrainer effect of ethanol. The calculations with ethanol as entrainer indicate that the molecular cavity and contact interaction are changed so as to increase the solubilities. Based on the calculations, the suitable amount of ethanol as an entrainer is estimated to be 0.02 mole fraction for both 6-gingerol and 6-shogaol with an improved solubility of 1.86 and 1.76 times, respectively. In general, the addition of the entrainer will improve the recovery and operating parameters at a milder operating condition. This approach may be applied to other bioactives and will further strengthen the use of water as a solvent in natural extracts.

Peanut skin is a waste of peanut industries especially peanut butter industries. Peanut skin contain high antioxidant and high nutritional values. The objective of this study was to optimize the effect of parameters to obtain high extract yield and high antioxidant activity by using supercritical carbon dioxide and co-solvent ethanol. A Box-Behnken design (BBD) was used to optimize the extraction process at the condition temperature (40, 55 and 70 ºC), rate of co-solvent ethanol (2.5, 5, and 7.5 % Vethanol/Vtotal), and extraction pressure (10, 20 and 30 MPa). The extraction time was 3 hours. The optimum condition to obtain yield of extraction and antioxidant activity 22.05 MPa, 62.76 °C and 6.03 %(Vethanol/Vsolvent) with 15.404 % yield extract and 94.040 % antioxidant activity.

Extract from plants have been reported to contain valuable bioactive compounds that have potential in promoting antioxidant activity. The present study was aimed to investigate the extracts of two plants available in Southeast Asia, Eurycoma longifolia and Swietenia macrophylla for their primary metabolite contents, phenolic contents, antioxidant and anti- tyrosinase activity. Two types of solvents were utilised in the extraction process of both plants. Ethyl acetate found to be a better solvent for isolation of primary metabolite compound compared to methanol. For Folin-Ciocalteu assay, methanol extract of Swietenia macrophylla possed higher phenolic content while for Eurycoma longifolia, ethyl acetate extract had higher phenolic content. In DPPH assay, the radical scavenging activity of extracts were strongly correlated to the total phenolic content based on the percentage of DPPH radical scavenging of each extracts (p

The methanol, ethyl acetate and petroleum ether crude extracts of mangosteen pericarp and α- mangostin were evaluated for the antioxidant capacity and tyrosinase inhibition properties. The ferric reducing antioxidant power (FRAP) assay was used to investigate their antioxidant capacity. Tyrosinase inhibition effect was evaluated using mushroom tyrosinase inhibition assay. Methanol extract has higher antioxidant reducing capacity (m= 1.621), compared to the rest of the extracts. Meanwhile, ethyl acetate extract and α- mangostin showed potent tyrosinase inhibition activities as compared to Kojic acid, a well- known tyrosinase inhibitor. It is observed that tyrosinase inhibition effect is antioxidant independent as ethyl acetate extract possessed low antioxidant capacity. This study suggests direct tyrosinase inhibition by ethyl acetate extract of Garcinia mangostana.

This article discusses the application of mixed reverse micelles in downstream processing of antibiotics. Purification and recovery processes for antibiotics in downstream processing are major expenses, about 70% of the total cost of production, giving them a significant impact on manufacturing cost. Moreover, there are a number of challenges and difficulties in the separation process requirements for antibiotics, since the mixture is quite complex, with broth, hazardous solvents, by-products, intermediate material, and impurities; in addition, antibiotics are easy to denature. Therefore, the development of effective separation techniques is required to produce high-purity of biomaterials. The use of reverse micelles is thought to be among the most promising due to the process's high selectivity and efficiency. Most studies on reverse micelle extraction technology have been performed by using anionic surfactant sodium bis (2-ethyl-1-hexyl) sulfosuccinate (AOT). However, the activities of antibiotics hoste...

Catechin that is known for its antioxidant, antihypertension and anticancer properties can be obtained from Areca catechu. In this study, accelerated water extraction (AWE) method was used to extract catechin from A. catechu seeds. The extraction parameters tested were temperature (120, 140 and 160 °C), static time (5, 10 and 15 min) and static cycle (1, 2 and 3 cycles). A. catechu extracts were analysed using liquid chromatography time-of-flight mass spectrometry to quantify the amount of catechin. Highest oil yield of 390.00-mg oil/g sample was obtained at temperature of 140 °C, 15 min of extraction time and 3 cycles. On the other hand, the highest catechin amount of 0.0716-mg catechin/g sample was obtained at 140 °C, 10 min and 2 cycles. The effect of extraction temperature was studied using the second-order kinetic model, and it showed good regression coefficient of more than 0.99. It suggests that the model could be applied to describe the extraction of catechin from A. catechu seeds. Based on the model, the initial extraction rate, the equilibrium extraction capacity and the extraction rate coefficient were evaluated to explain the AWE process at temperatures ranging from 120 to 160 °C. © 2014 Curtin University of Technology and John Wiley & Sons, Ltd.

Zingiber officinale or ginger known for its high medicinal compounds is extracted using hot compressed water (HCW). The two most important bioactive compounds namely 6-gingerol and 6-shogaol in the ginger extracts are analyzed using HPLC. The effects of temperature and time of extraction on 6-gingerol and 6-shogaol are studied using HCW extraction. It is found that HCW extraction can extract these two bioactive compounds; 6-gingerol at 130 °C and 30 min whilst 6-shogaol at 170 °C and 20 min. This finding shows that HCW extraction is potentially used in selective extraction of bioactive compounds at different conditions of HCW. The kinetics of extraction for both bioactive compounds is studied from the optimum temperatures obtained. The overall mass transfer coefficient which represents the extraction efficiency is calculated using mass transfer model. The optimum values of the overall mass transfer coefficient (k) for 6-gingerol is 8 × 10−7 m/s at 130 °C whilst for 6-shogaol, is 18 × 10−7 m/s at 170 °C using HCW extraction. The relationship between the overall mass transfer coefficient and the dielectric constant of various solvents for 6-gingerol is identified. Similar relationship is identified for 6-shogaol using HCW as solvent. The dielectric constant does not contribute to the extraction efficiency of 6-gingerol and 6-shogaol.

This work was aimed to characterize ash-rich adsorbent derived from palm oil mill effluent sludge (POME sludge) for heavy metals removal from aqueous solution. The adsorbents were characterized according to specific surface area, surface morphology and elemental compositions. Sludge adsorbent exhibits high adsorption capacity for both copper(II) and lead(II), while its ash derivative demonstrates comparable removal of lead(II). Results indicate the important role of sludge ash in the adsorption of heavy metals. The study suggests the potential use of ash-rich POME sludge for industrial wastewater treatment.

Supercritical fluid extraction of α-tocopherol and β-carotenoids from crude palm oil offers an excellent method over other existing conventional methods. Supercritical fluid extraction was developed in the early and mid-1980s to reduce the use of harmful organic solvent in the laboratory. The present paper reviews the applications of supercritical fluid extraction technology in extraction of palm oil using CO2and R 134a fluids. Carbon dioxide is non- toxic, having low critical pressure (74 bar) and temperature (32°C) which minimize the thermal degradation of product but it has a limited dissolving power for solutes of high polarity and high molecular weight in the supercritical state and it also requires higher pressure of upto 500 bar and this high pressure operation requires high operation cost and high capital cost. R134a is an alternative low pressure, non-reactive, non-flammable, non-toxic, non-ozone depleting and has comparable solvent properties as that of CO2. R-134a needs only its temperature or pressure to be controlled in order to control the conditions of extraction or product isolation. This allows simple control of the process.

This work was aimed to evaluate the adsorptive nature of palm oil mill effluent sludge ash for methylene blue dye removal in aqueous solution. Two types of palm oil mill effluent sludge collected from different treatment ponds, i.e. anaerobic and biopolishing were burnt to ash, and treated with 5 M HCl. The treated and untreated adsorbents were characterized for surface area and morphology. Methylene blue dye adsorption was carried out in laboratory at room temperature, and the adsorption data were analyzed based on equilibrium isotherm and kinetic models. The surface area of ash-adsorbents was found to increase more than 12 times after HCl treatment. The highest surface area recorded was 218 m2/g. Equilibrium data of ash-adsorbents obeyed Langmuir isotherm to linear approximation suggesting the monolayer uptake of methylene blue dye. The highest maximum uptake of 50.7 mg/g methylene blue dye (50% removal) was demonstrated by HCl-treated biopolishing ash-adsorbent at initial concentration of 200 m...

The work was aimed to investigate the effect of heat treatment of manure-compost-based activated carbons on the adsorption of copper from aqueous solution. Activated carbons were characterized according to physical structures and surface functional groups. All equilibrium data of activated carbons formerly treated at different temperatures obeyed Langmuir model to linear approximation. Results showed that copper ions favorably adsorbed onto the mesopores at lower equilibrium concentrations and subsequently changed to the micropores at higher equilibrium concentrations. It was found that the increase in electron density upon heat treatment offered higher tendency for the uniform amount of protons to occupy the surface sites. Analysis of Scatchard plots suggested that the affinity driven by the mesopores toward copper ions was stronger than that of the micropores.

In this study, supercritical carbon dioxide is chosen for the extraction and purification of omega-3 fatty acids from Hevea brasiliensis (rubber) oil because this method is environmental friendly and the extracted oil has improved nutritional and functional values. In addition, extraction using this method also can prevent organic solvent residual inside the extracted oil. During the extraction using supercritical carbon dioxide, the oil yield is increased with the increase of temperature and pressure. The best operating condition is pressure of 30 MPa, and temperature of 80 C giving 21.4714% oil yield. The analysis of fatty acids composition is using gas-chromatography. The extracted rubber seeds oil is converted to fatty acids methyl esters (FAME) make it more accessible for chromatogram analysis. From the analysis, the omega-3 fatty acids inside rubber seeds oil especially alpha-linolenic acid (ALA) is the highest compare to soybean oil and olive oil. Beside this, rubber seeds oil also contains oleic acid which is omega-9 and linoleic acid is omega-6. This is the reason rubber seeds oil can be regard as oleic-linolenic seed oil. Alpha-linolenic acid is the precursor to convert polyunsaturated fatty acids (PUFAs) to docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Oleic acid (Omega-9) has the potential for heart protection and cancer prevention but still in the state of prove. On the other hands, the linoleic acid, the element of omega-6 has the benefits to treat to treat arthritis and autoimmune disease. Therefore, rubber seeds oil has very high potential to be developed into difference products in difference industries such as pharmaceutical, cosmetics, oleochemical and foods.

A rapid identification, classification and discrimination tool, using Fourier Transform Infrared (FTIR) spectroscopy combined with Principal Component Analysis (PCA), was developed and applied to determine the profile of the Supercritical Fluid Extraction (SFE) of Parkia speciosa seeds under various temperature and pressure conditions (313, 323, 333, 343, 353 and 363 K and 20.68, 27.58, 34.47, 41.37, 48.26, and 55.16 MPa). The separation and identification of the compounds was carried out by Gas Chromatography coupled with Time of Flight Mass Spectrometry (GC/TOF-MS). This technique has made it possible to detect the variability obtained under different SFE conditions and the separation of different chemical compounds in P. speciosa seeds. The FTIR-PCAresults were verified by GC/TOF-MS, and the FTIR-PCA method successfully identified the unsaturated carboxylic acids with the highest percentage area under the different conditions.

Extraction of Orthosiphon stamineus oil has been the subject of current study. In this case first based on Box–Behnken experimental design method, experimental work was carried out to find the effect of temperature, extraction time and the number of extraction cycles on extraction yield. Seventeen different experimental data were obtained and response surface modeling (RSM) was employed to find relation between extraction yield and process variables. A second order polynomial based on statistical analysis with 95% confidence limits was found as the best estimator of extraction yields. In the next step of the study, artificial neural network (ANN) as a soft computing method was applied to predict the oil yield. A multilayer perceptron (MLP) was used in this study. In order to implement an ANN, temperature, extraction time and the number of extraction cycles were selected as input variables and oil yield was considered as target variable. 70% of data were utilized for training and 30% of the remaining data were used for testing the best obtained network. The results illustrated that ANN method is more reliable than RSM method for extraction prediction and optimization. The optimum operating conditions were found at 100 °C, 10 min and 2 cycles.

This work was aimed to investigate the effect of helium degassing of cattle-manure-compost (CMC) based activated carbons on the adsorptive removal of copper ions from aqueous solution. Degassing temperatures were 500℃, 800℃ and 1000℃. Activated carbons were characterized according to surface chemistry and pore structures. Adsorption of copper ions was carried out using the conventional bottle-point technique to which the equilibrium data were correlated to Langmuir and Freundlich models. Results indicated that the uptake of copper ions could be well characterized by Langmuir model. It was found that the adsorption of copper ions decreased with significant decrease in surface area as a result of helium degassing at higher temperature. The increase of electron density on graphene layers offered higher affinity towards copper ions at lower equilibrium concentration. It was inferred that copper ions favorably adsorbed on mesopores at lower equilibrium concentration and switched to micropores at higher equilibrium concentration.

Teknik reka bentuk komposit pusat dalam kaedah gerak balas permukaan (RSM), telah dipilih untuk memeriksa pengaruh parameter-parameter pengeringan sembur terhadap kandungan lembapan dan ketumpatan pukal serbuk buah naga. Pemboleh ubah-pemboleh ubah tak bersandar dengan julat seperti yang disebutkan telah diuji kaji: suhu masukan (156-224°C), kadar aliran suapan (16.6-33.4 ml/min) dan kepekatan maltodextrin (31.6-48.4%). Keputusan menunjukkan bahawa data eksperimen dapat diwakili oleh bentuk polinomial tertib kedua. Bagaimanapun, hanya istilah linear mempunyai pengaruh mutlak terhadap keadaan serbuk. Parameter-parameter terbaik untuk mencapai nilai kandungan lembapan terendah adalah suhu masukan 224°C, kadar aliran suapan 22.9 ml/min dan kepekatan maltodextrin 40%, dengan jangkaan 3.88% kandungan lembapan. Nilai ketumpatan pukal yang maksimum iaitu 0.45 g/ml dicapai pada suhu masukan 156°C, kadar aliran suapan 16.6 ml/min dan kepekatan maltodextrin 48.4%. Kata kunci: Kaedah gerak balas permukaan; sembur kering; buah naga Central Composite Design technique from Response Surface Methodology (RSM) was used to investigate the effects of spray drying conditions on red-fleshed pitaya powder moisture content and bulk density. The spray drying independent variables and ranges are inlet air temperature (156-224°C), feed flow rate (16.6-33.4 ml/min) and maltodextrin concentration (31.6-48.4 %). Results showed that the data were adequately fitted to second order polynomial model. However, only linear terms proved to be significant for powder attributes. The best spray drying conditions within the experimental ranges for minimum powder moisture content of 3.88% would be inlet air temperature, feed flow rate and maltodextrin concentration of 224°C, 22.9 ml/min and 40% respectively. The maximum powder bulk density of 0.45 g/ml was obtained at inlet air temperature of 156°C, 16.6 ml/min feed flow rate and 48.4% maltodextrin concentration. Key words: Response surface methodology; spray-drying; red-fleshed pitaya

The objective of this study was to study and compare the effect of particle size on the modified supercritical carbon dioxide and soxhlet extraction in terms of oil yield and antioxidant activity. The mean particle sizes of 300, 355, 425, and 500 µm for modified supercritical carbon dioxide extraction, the temperatures of 40 and 70 °C, pressure of 10 and 30 MPa, flow rate of CO2 3 mL/min, and rate of co-solvent 5% were used in this study. Meanwhile, for soxhlet extraction, the extraction time was 6 hr with ethanol, hexane, and water as the solvent. DPPH method was used to analyze the antioxidant activity of the extract. The results showed that 425 µm gave the highest yield extract on the modified supercritical carbon dioxide extraction (15.53%), soxhlet extraction (36.28%), antioxidant activities for modified supercritical carbon dioxide (93.43%), and soxhlet extraction (62.21%). Single sphere model has successfully fitted the experimental data of modified supercritical carbon dioxide with error below 5% with the highest diffusivity coefficient was 6.794E-12 m2/s at operating conditions was 10 MPa, 40 °C and particle size 425 µm. Practical applications: Peanut skin as waste of peanut industries has many bioactive compounds and high antioxidant activities. Therefore, supercritical carbon dioxide extraction as a green technologhy carry out the extract from peanut skin. Addition of ethanol as modifier is needed to enhance the polarity of supercritical carbon dioxide to extract polar compounds inside of peanut skin. To begin with, the extract of peanut skin using modified supercritical carbon extraction is compared with soxhlet extraction as conventional extraction. Although soxhlet extraction obtained high yield extract, modified supercrirical carbon dioxide gave higher antioxidant activities. The antioxidant activity of modified supercritical carbon dioxide extraction was more than 90%. Furthermore, effect of particle size in the extraction processes was determined to obtain high extract yield and antioxidant activity. the result shows that 425 µm gave the maximum yield extract and antioxidant activity on the modified supercritical carbon dioxide and soxhlet extraction.

Pithecellobium Jiringan (P. Jiringan) is traditionally known as natural herb consists of several medicinal compounds (vitamin E). Supercritical carbon dioxide extraction (SC-CO2) has been proven as potential method to extract interest compound from herbs. By altering pressure and temperature, the specific compound can be extracted. In this study, the SC-CO2 operating conditions are pressure (20.68 MPa to 55.16 MPa) and temperature (40°C to 80°C) in one hour extraction regime was used to extract vitamin E from P. jiringan. The quantification of vitamin E was analysed with Gas Chromatography Time of Flight Mass Spectrometry (GC-TOF-MS). The responses are overall oil yield and vitamin E yield. The overall oil yield was obtained at the highest condition of 55.16 MPa and 80°C with asymptotic yield of 8.06%. In contrast, the highest amount of vitamin E obtained is 0.0458mg/g sample (80.14 ppm) at the lowest extraction condition of 20.68 MPa and 40ᵒC.

The aim of this study is to investigate the influence of different composition of cellulose acetate phtalate (CAP) on the membrane structural properties of polysulfone (PSf) membrane which in turn affect the separation performance of PSf/CAP blend membrane. The PSf/CAP blend membranes were prepared by using casting solutions contain 17 wt% of polymer via wet phase inversion process. The results showed that increasing the composition of CAP in PSf/CAP blend membranes increased molecular weight cut-off (MWCO), average pore size and pore density which then increased protein solution permeate fluxes but reduced proteins rejection of PSf/CAP blend membranes. Pure PSf membranehas the lowest membrane structural properties compared to blend membranes. This characteristic contributed to decrease in protein permeation flux and increase proteins rejection.

Experiments involving subcritical carbon dioxide extraction of palm oil from treated palm mesocarp were done to determine palm oil yield and concentration of beta-carotene. As comparison, the conventional method of Soxhlet Extraction with six different solvents was used. The overall oil yield was measured as weight of oil per weight of sample, while anti-oxidant activity was determined using 2,2-diphenyl-1-picryihydrazyl (DPPH) radical scavenging method. The sub-critical extraction was conducted at a constant temperature of 30˚C and four different pressures at 10 MPa, 15 MPa, 20 MPa and 25 MPa. The sub-critical extraction produced high concentration of beta-carotene than soxhlet extraction, even though the oil yield was lower. Furthermore, the anti-oxidant analysis showed a similar trend as the concentration of beta carotene. The best condition of sub-critical extraction was obtained at 25 MPa and 30˚C.

A promising technique of Green Supercritical Carbon Dioxide (SC-CO2) process was developed for the extraction of squalene from palm oil mesocarp. In this study, the green SC-CO2 was compared with the conventional Soxhlet extraction for quantify the best extraction method. The independent variables in SC-CO2 were selected as follows: temperature (45–75 °C), pressure (16–30 MPa) and CO 2 flow rate (2–5 ml/min). The responses are oil yield and the concentration of squalene. On the other hands, the conventional soxhlet extraction condition was type of solvents. Furthermore, the conditions of SC-CO 2 extraction for squalene and oil yield were optimized by response surface methodology (RSM) following Box-Behnken Design (BBD). The optimum conditions were at pressure (16 MPa), temperature (45.01 °C) and CO 2 flow rate (2 ml/min) and the concentration of squalene was 0.506%. Meanwhile for soxhlet extraction method showed the concentration of squalene was 0.143% with chloroform. In overall, the results indicated the green SC-CO 2 was the best an alternative technique.

In this study, the influence of supercritical extraction parameter on the oil extraction of Mahogany (Swietenia mahagoni) was investigated. Supercritical extraction was carried out using the operation pressures of 20, 25 and 30 MPa, and temperature was varied in 40, 50 and 60°C. The parameter used for CO2 flow rate was constant, 2 mL/min, with extraction time of 180 min by using matrix particle size of 0.75 mm. Then, the extracted oils were tested for cytotoxic activity and properties. MTT assay was used as in vitro study to investigate the cytotoxic properties of the extracted on human fibroblast cells (HSF 1184). The study reveals that the extraction yield depends on the pressure and temperature. There is a significant difference of 40, 50 and 60°C at different pressures, whereby increasing pressure leads to significant increase extraction yields. MTT assay results indicate that all the extracts under different extraction parameters are non-cytotoxic. The results confirmed that supercritical extraction could be a promising technique to produce high quality botanicals extracts, free of solvent and non-cytotoxic with significant cost savings.

Application of water-in-oil emulsion in the formulation of color cosmetic is very common. However using natural water-soluble pigments as cosmetic colorant is not general in the cosmetic industry although we knew the side effect from using synthetic colorant. This study concerns one of the most important problems in using natural pigment which was to obtain the lip moisturizer formulation and to determine emulsion stability. Roselle is a local potential pigment source which is added into castor oil as the oil phase with the aid of Span 80 and Tween 85 as emulsifier. Several emulsions were prepared using different proportions of emulsifiers and the most suitable hydrophilic lipophilic balance (HLB) value for color emulsions was determined to continue with the finding of stable formulation. In addition, stable formulation was determined and emulsions stability were studied during the observation period. Emulsions were analyzed by using viscosity measurement, in order to determine a suitable formulation of emulsion. The formulation of emulsion was stabilized under HLB value of 5.3 which is 75% of Span 80 and 25 % of Tween 85.

Andrographis paniculata plant has been widely used for traditional medicine such as curing fever, diarrhoea, and inflammation. In this study, the main component (Andrographolide) is extracted from the leaves of A. paniculata using supercritical carbon dioxide (Sc-CO2) and Sc-CO2 assisted by methanol as a modifier solvent. The methanol soxhlet extraction as a standard method was used to compare with the Sc-CO2 extraction. This work also focuses on the determination of anti-oxidant activity of Sc-CO2 extraction extracts of A. paniculata plant. The Sc-CO2 extracts of A. paniculata for both Sc-CO2 extractions with and without modifier showed promising antioxidant activity. Free radical scavenging potential of both Sc-CO2 extractions of A. paniculata plant was evaluated by using reducing power. In this method, ascorbic acid was used as a standard for determining reducing power. Both Sc-CO2 extract of A. paniculata plant exhibited appreciable activity as compared to the methanol soxhlet extract, indicating that A. paniculata has promising free radical scavenging activity.

Traditional medicinal plants such as Swietenia mahagoni and Andrographis paniculata are rich with bioactive compounds. The phenolic composition and antioxidant activity of methanol extract from Swietenia mahagoni and Andrographis paniculata were studied. They were extracted by Soxhlet extraction of 70% methanol solvent. The results obtained from this study showed Andrographis paniculata gave highest percentage yield by 19.94% compared to Swietenia mahagoni at 11.86%. In antioxidant activity, Andrographis paniculata and Swietenia mahagoni showed 89.93% and 60.77% respectively. While for total phenolic content highest in extract of Swietenia mahagoni by 55.0 mg/g and Andrographis paniculata only 7.7 mg/g.