Clay catalyst has received much attention to replace the homogeneous catalysts in the esterification re-action to produce fatty acid methyl ester as the source of biodiesel as it is low cost, easily available, as well as environmental friendly. However, the use of unmodified clay, in particular montmorillonite K10 (MMT K10), for the esterification of fatty acids showed that the acid conversion was less than 60% and this is not preferable to the production of biodiesel. In this study, synthesis of stearic acid methyl ester using Cu2+-MMT K10 (Cu-MMT K10) was successfully optimized via response surface methodo-logy (RSM) based on 3-variable of Box-Behnken design (BB). The parameters were; reaction time (5-180 minutes), reaction temperature (80-120 �C) and concentration of Cu2+ in MMT K10 (0.25-1 M). The use of RSM in optimizing the conversion of stearic acid was successfully developed as the actual experi-mental conversion of stearic acid was found similar to the actual values under the optimum conditions. The model equation predicted that the following conditions would generate the maximum conversion of stearic acid (87.05 % reaction time of 62 minutes, a reaction temperature of 80 'C and catalyst used is 1.0 M Cu-MMT K10. This finding can be considered as green catalytic process as it worked at moderate reaction temperature using low cost clay catalyst with a short reaction time.

Lard consumption is forbidden for Muslim people and researches have been done to differentiate lard from other fats for Halal authentication. Therefore, this study was conducted to differentiate lard from other edible fats after heating treatments using Fourier transformed infrared spectroscopy (FTIR) and multivariate data analysis techniques. Five samples of fats from different sources; lard, chicken, mutton, tallow and palm based shortening were heated at different temperature (120, 180 and 240°C) and time (30, 60, 120 and 180 min). The spectra in the form of multivariate data were acquired using FTIR spectroscopy. Principal components analysis (PCA), k-mean cluster analysis (k-mean CA) and linear discriminant analysis (LDA) were used to compare the ability of each technique to differentiate the fats after the heating treatments. It was found that the combination of PCA with k-mean CA was able to differentiate heated fats according to its origin. LDA method was successfully used to classify 80.5 % of samples in its group. Thus, PCA, CA and LDA can be used as multivariate data analysis to differentiate the heated edible fats.

The esterification of free fatty acids with alcohols using montmorillonite (MMT) clay as heterogeneous catalyst is one of the methods to produce fatty acid alkyl ester that can be used as alternative renewable biofuels. However, the unmodified MMT gives low conversion of free fatty due to the limitation of acid sites in the clay structure. This work focuses on preparation of an environmental friendly catalyst from montmorillonite K10 (MMT K10) clay catalyst for the esterification of oleic acid with various alcohols. Esterification of oleic acid with alcohols has been carried out in the presence of metal exchanged MMT K10 (M-MMT K10; M = Fe3+ and Cu2+). The concentrations of both Fe3+ and Cu2+ precursors were varied at 1 M and 4 M. The effect of different alcohols used, molar ratio of reactants and catalyst loading on the esterification reaction was investigated. Among the exchanged clay catalysts, 4 M Fe-MMT K10 was found to be more active for the esterification of oleic acid with methanol. The maximum oleic acid conversion (ca. 68.5%) was achieved after 3 hours of reaction at the reaction temperature of 60 oC with molar ratio of methanol to oleic acid of 10:1 and catalyst loading of 5 wt% relative to the mass of oleic acid. The catalytic activity was found to be directly related to the amount of cation used in the modification step and Bronsted acidity of metal exchanged MMT K10 clay catalyst.

Natural feldspar from Tanah Putih, Gua Musang, Kelantan (Malaysia) was physico-chemically characterized using X-ray Diffraction (XRD), Surface Area and Porosity Analysis (ASAP) and Energy Dispersive X-ray (EDX) techniques. The feldspar was found to be of the potassium (K) type, with major components containing aluminum (Al), and silicon (Si). The feldspar also possesses 38.307 nm mean pore diameter and 18.717 m2/g surface area. Candida rugosa (CRL) was then immobilized onto natural feldspar by physical adsorption method. About 49.96% of protein content was immobilized onto the support. The catalytic activity of the immobilized lipase was determined by the esterification reaction using oleic acid and oleyl alcohol. The effects of various reaction temperatures, stability in organic solvent, and lipase recyclability on the esterification reaction for the native and immobilized lipase were investigated. Feldspar-immobilized lipase exhibited higher activity than that of the native lipase. Immobilized lipase retained its activity ca. 50% even after incubation at high temperature (70°C) with the optimum reaction temperature of 40°C, long incubation in hexane up to 10 days and after ten repeated cycles used. Feldspar-immobilized lipase also showed considerably efficient reusability where it was not easily leached even after being washed with large amount of hexane (20 mL). These results showed that physical adsorption method is suitable for the immobilization of lipase onto feldspar.

Co (II) complex (CMLA) was investigated to evaluate the rate of wound healing in rats. Animals were placed into four groups: gum acacia, Intrasite gel, 10 and 20 mg/ml of CMLA. Wounds were made on the dorsal neck area, then treated with Intrasite gel or CMLA; both of these treatments led to faster healing than with gum acacia. Histology of the wounds dressed with CMLA or Intrasite gel displayed a smaller scar width, required less time to heal and showed more collagen staining and fewer inflammatory cells in comparison to wounds dressed with the vehicle. Immunohistochemistry for Hsp70 and TGF-? showed greater staining intensity in the treated groups compared to the vehicle group. Bax staining was less intense in treated groups compared to the vehicle group, suggesting that CMLA and Intrasite gel provoked apoptosis, responsible for the development of granulation tissue into a scar. CD31 protein analysis showed that the treated groups enhanced angiogenesis and increased vascularization compared to the control group. Furthermore, a significant increase in the levels of GPx and SOD and a decrease in MDA were also observed in the treated groups. This results suggest that CMLA is a potentially promising agent for the wounds treatment. � The Author(s) 2016.

Shape memory polyurethanes (SMPU) are one of the advanced materials that have potential applications in the field of biomedical particularly vascular stent. This paper studies the effect of incorporating palm oil polyol (POP) up to 40% molar ratio in place of petroleum-based polyol in the preparation of SMPU due to environmental concern. Polycaprolactone diol was utilized as the soft segment while 4,4?-diphenylmethane diisocyanate and 1,4-butanediol as the hard segments. The SMPU was prepared using two-step prepolymer method, and the fabricated samples were characterized to study the effect of POP on the thermal properties, tensile, and shape memory behavior of polyurethane. The results obtained have shown that SMPU with incorporation of POP showed good shape fixity (100%) and elongation at break (245%) up to 20% molar ratio of POP. The presence of dangling chains of fatty acid in POP was believed to enhance the flexibility of SMPU molecular chains by acting as a plasticizer. On the other hand, the shape recovery of SMPU remains high even at 40% molar ratio of POP, and the thermal stability of SMPU increased with the addition of POP. It is proposed that the synthesized POP-based SMPU is a suitable candidate for cardiovascular stent as they possessed desired thermal, mechanical, and shape memory properties. � 2018 John Wiley & Sons, Ltd.

Montmorillonite K10 (MMT K10), the major clay mineral commercially available can be treated to improve its properties and thus can be utilized for a broad range of organic reaction including esterification of fatty acids for biodiesel production. However, the use of unmodified MMT K10 in esterification of fatty acids showed that the acid conversion was less than 60 %. The aim of this study is to utilize available material i.e. MMT K10 modified with Cu2+, Al3+ and Fe3+ at various concentrations as catalyst for the esterification of acetic acid and stearic acid. The x-ray diffraction and elemental analysis of the materials were successfully characterized. After characterization, the materials were evaluated for the esterification of acetic acid and stearic acid with methanol. Prepared catalysts were able to give the highest acid conversion of up to 75% relative to the unmodified MMT K10 revealing the potential of M-MMT K10 as catalyst for esterification in biodiesel production. � Copyright International Association of Engineers.

Many countries produced biodiesel from crude vegetable oil. However, current vegetable oil feedstock to produce biodiesel slow the growth of biodiesel blend implementation due to the high cost of feedstock production. As a result, waste cooking oil (WCO) is claimed to be economic and readily available without cultivation and highly potential feedstock for high yield biodiesel. In this study, Fe-exchanged montmorillonite K10 (Fe-MMT K10) was employed as a catalyst in converting WCO to biodiesel. In comparison, Fe-MMT K10 was able to produce 95.26% biodiesel, which is higher than biodiesel produced using unmodified MMT K10 as catalyst and reaction without catalyst (38.39% and 29.50%, respectively). The full process of biodiesel production was carried out by response surface methodology (RSM) in conjunction with the central composite design (CCD) for statistically optimization and modelling. From the ANOVA, it was found that the production of biodiesel achieved an optimum level of 92.74% biodiesel at 134.07 °C, under a specific optimized condition of 6.32 h reaction time, 4.68 wt% of catalyst and 11.77:1 methanol to oil ratio.

The modification of montmorillonite K10 with Fe3+ was investigated to study the optimum ion-exchange occurred in the interlayers of clays. Montmorillonite K10 was modified to be applied as a catalyst in biodiesel production from waste cooking oil (WCO). Three methods to optimize the ion-exchange process were investigated. For method 1 and method 2, respective 14% and 27% by mass of Fe in montmorillonite K10 were stirred in a closed cap system for 7 hours while method 3 applied 20% of Fe stirred with montmorillonite K10 for 24 hours until it became mold and slurry. The ability of ion-exchange was tested using SEM/EDX. It was found that 1.21% Fe composition increased by using method 1 while 2.66% Fe increased using method 2. The highest Fe exchange was detected using method 3 with 5.23% increment. For more accurate result, 20% Fe-MMT K10 from method 3 was characterized using XRF and it was found that the ion exchange occurred with interchangeable Ca2+. In correlation, the effect of Fe increment on acidity was studied by using TPD-NH3. Naturally, montmorillonite K10 possessed 0.232 mmol/g of acidity. The results found that the highest acidity was detected for 20% Fe-MMT K10 (14.261 mmol/g). The application of montmorillonite K10 on biodiesel production increased the yield up to 38.39% compared to the reaction without catalyst (26.80%). With the aid of modified montmorillonite K10, 66.54% and 69.32% biodiesel were produced using catalyst from method 1 and 2 respectively. Amazingly, an outstanding yield was produced by using catalyst from method 3 (84.58%). Therefore, 20% Fe-MMT K10 catalyst was selected for further biodiesel optimization via conventional method. It was found that 96.49% biodiesel was successfully produced with 28.65% acid conversion at 150 °C, 6 h, 12:1 methanol: oil and 4 wt.% mass of catalyst. The investigations on acid conversion and biodiesel yield proved that the modification of montmorillonite K10 with 20% Fe is the optimum and the catalyst can undergo both esterification and transesterification reactions simultaneously to produce optimum biodiesel yield. © 2020, Malaysian Society of Analytical Sciences. All rights reserved.

The aim of this work is to develop a new type of polymer matrix which can be used to study the reactive intermediates produced from UV photolysis of metal carbonyl complexes measured with FTIR as well as UV-vis spectroscopy. The photochemistry of Cr(CO)6impregnated in Teflon-AF polymer with the presence of N2, CH4and even weak ligand i.e.Xe and He were conducted at extremely low temperature. Photolysis of Cr(CO)6under N2environment produces up to four carbonyl groups being replaced with the N2. Meanwhile, the photochemistry of Cr(CO)6under Xe and CH4produce the reactive complexes of Cr(CO)5(Xe) and Cr(CO)5(CH4)respectively. Teflon-AF was found to be the suitable matrix material as the �C�F� bond binds very weakly to the metal center. � 2016 Penerbit UTM Press. All rights reserved.

6-hydroxy-4-methyl-5,7-(bis-p-chlorophenylazo)coumarin has been synthesized and characterized by CHN elemental analysis, FTIR,1H-NMR-spectroscopy and mass-spectral data. Cytotoxic screening by MTT assay was carried out on the compound against breast cancer cells. The overall results from preliminary screening program revealed that the cell proliferation was highly inhibited by 6-hydroxy-4-methyl-5,7-(bis-p-chlorophenylazo) coumarin with the value of 2.81%, at concentration of 30 ?g mL?1 compared with the untreated control cells and also possessed a good chelating activity with IC50 value 1.87 ?g mL?1. It is suggested that the cytotoxic activity is affected by hydroxyl and halogen groups as these groups have high electron affinity and high electronegativity. � 2016 Dalal M. Ibrahim, Juliana Jumal and Farah Wahida Harun.

Background/Objectives: One of the severe disease intimidating human health and continues to be a main health problem worldwide is cancer. Hence, discovering new compounds with powerful anticancer activity is of extreme important. The main objective of this paper is the synthesize 6-hydroxy-4-methyl-5,7-(bis-phenylazo) coumarin and its complexes and evaluate the cytotoxic activity of the ligand and complexes against breast cancer cells. Methods/Statistical Analysis: A novel compounds of 6-hydroxy-4-methyl-5,7-(bis-phenylazo) coumarin have been synthesized by 6-hydroxy-4-methylcoumarin. The complexation of nickel (II), copper (II) and cobalt (II) using this ligand gave salt type complexes with the formula of M(C22H15O3N4) the compounds were characterized by microelemental analysis, infra-red, nuclear magnetic resonance spectroscopic techniques and molar conductivity. Cytotoxic activity for the ligand and the complexes were evaluated against breast cancer cells by using MTT assay and the absorbance at 570 nm was measured by ELISA reader. Findings: The CHN analysis of the compounds are in good agreement with the calculated values and the spectroscopic analysis of the complexes indicated that the ligand coordinated to the metal centres as polydentate ligand in bisazocoumarin and form a distorted octahedral arrangement around nickel (II), copper (II) and cobalt (II) centres. The molar conductivity of the divalent metal ions complexes was small which directly supports the fact that all of the investigated complexes are non ionic. The overall results of cells MCF7 breast cancer revealed of cell proliferation was much more highly inhibited by the ligand and complexes Cu, Co and Ni with cell viability 5.21%, 17.36%, 46.20% and 74.43%, respectively at a concentration of 30 mg/ml compared to untreated control cells and IC50 values of the ligands and complexes of Cu, Co and Ni were 1.87, 1.87, 30 and >30 g/ml, respectively. Improvements: Lastly, some suggestions were presented to use these compounds in vivo should be assessed to obtain worthy anticancer drugs.