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This study investigates the potential of N-octyl chitosan derivatives, namely N-octyl-O-sulfate chitosan (NOOSC), N-octyl-N-succinyl chitosan (NONSC) and N-octyl-O-glycol chitosan (NOOGC) as amphiphilic carrier agents for atrazine in water-insoluble herbicide formulations. The N-octyl chitosan derivatives were characterised using several analytical instruments such as Fourier Transform Infrared (FTIR) Spectrometer, CHNS-O Elemental Analyser (CHNS-O), Transmission Electron Microscope (TEM), Thermogravimetric Analyser (TGA), Differential Scanning Calorimeter (DSC) and Fluorescence Spectrometer. The encapsulation of atrazine by N-octyl chitosan derivatives was studied using a High Performance Liquid Chromatography (HPLC). The FTIR spectra of N-octyl chitosan derivatives confirmed the presence of hydrophobic and hydrophilic groups on chitosan backbone. TEM images revealed that N-octyl chitosan derivatives have formed self-aggregates with a spherical shape. The CMC values for N-octyl chitos.....

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In the present study, gelatin–carboxymethyl cellulose blend film was synthesized, characterized and applied for the first time to preserve cherry tomatoes (Solanum lycopersicum var. cerasiforme) and grapes (Vitis vinifera). Gelatin (Gel) film forming solution was incorporated with carboxymethyl cellulose (CMC) at three volume per volume (Gel:CMC) ratios, namely 75:25, 50:50 and 25:75. CMC treatment has improved the transparency, tensile strength (TS), elongation at break (EAB), water vapor permeability and oxygen permeability of gelatin films. A pronounced effect was obtained for 25Gel:75CMC film. The TS and EAB values were increased from 25.98 MPa and 2.34% (100Gel:0CMC) to 37.54 MPa and 4.41% (25Gel:75CMC), respectively. A significant improvement in antimicrobial property of gelatin films against two food pathogens, namely Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was obtained in the presence of CMC. The effectiveness of gelatin–CMC blend films to extend th.....

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In this study, gelatin-chitosan (Gel-Cs) blend films were prepared at three volume per volume ratios (Gel:Cs) namely 75:25, 50:50 and 25:75. The gelatin-chitosan blend films were applied for the first time to preserve cherry tomatoes (Solanum lycopersicum) and grapes (Vitis vinifera) in a 14- day preservation study. The addition of chitosan has improved the transparency value, tensile strength, percentage elongation at break, water vapour, oxygen permeability and antimicrobial properties of gelatin film. Of blended films studied, 25Gel:75Cs film exhibited the best functional and mechanical properties. The tensile strength and elongation at break values of 25Gel:75Cs film showed a significant increased by 26% and 63%, respectively. The presence of chitosan has enhanced the ability of gelatin film to inhibit two common food pathogenic microorganisms, namely Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Results from preservation study suggest that the gelatinchitosan b.....

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Development of low-cost, sustainable and environmentally friendly biodiesel is a key focus in the energy industry worldwide. It is known that selecting suitable raw feedstock materials and optimising an efcient transesterifcation process are crucial in biodiesel production. Efective and realistic strategies are imperative in order to boost the quantity and quality of biodiesel production. In fact, scientists and researchers have put great efort to improve the market value of their biodiesel products. In recent years, the feasibilities of several raw materials as feedstocks to produce biodiesel have been assessed by researchers.These materials were reported able to produce biodiesel that met international standards, namely  the American Society for Test and Materials D6751 and European Standard 14214. Although these biodiesel products have met the quality criteria, their fatty acid methyl ester (FAME) contents difer. This review focuses on optimum conditions (methanol/oil molar ratio, .....

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Biodiesel from insect larvae is an alternative to plant biodiesel, which have issues of using edible plants. On the contrary, insects can grow on waste. Although the conversion of larval lipids to biodiesel is known, characterisation of larval biodiesel is rarely reported. Here, black soldier fy larvae were cultivated for 20 days on kitchen waste. Larval lipids were extracted and converted to biodiesel by two-step transesterifcation. Analysis by optical polarisation microscopy from −5 to +15 °C showed tiny needle-like shaped crystals. Fourier transform infrared spectra of black soldier fy biodiesel revealed absorption bands at 1459 and 1435 cm−1 corresponding to methyl ester, the main functional group of biodiesel. Nuclear magnetic resonance (NMR) analysis confrmed the presence of methyl ester by showing peaks at 3.6 and 2.3 ppm by 1 H NMR, and at 176 and 51.56 ppm by 13C NMR. Overall, our results confrm the successful conversion of black soldier fy larval lipid to biodiesel. This.....

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Andrographis paniculata Ness is one of the plants that is under explored and could contain potentially active substances to serve as an antimalarial. Structure investigation of major compounds that have responsibility for the antimalarial activity of Andrographis paniculata Ness’s n-hexane extract is very important so that it is known whether the antimalarial activity is synergistic or from the major compounds. Menthol and dioctyladipate as major component from n-hexane extract of Andrographis paniculata Ness have been succesfully isolated using simple and inexpensive methods. The solvent system used are n-hexane : ethyl acetate (10:1) and n-hexane: chloroform (10:3) consecutively either for column or preparative thin layer chromatography. FT-IR, 1 H-NMR and GC-MS were used to determine the structure of compounds. The activity of n-hexane extract, menthol and dioctyladipate related to the inhibition of heme polymerization have been done comprehensively. The inhibition of heme polymer.....

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In this study, the effectiveness of lala clam (Orbicularia orbiculata) shell, a fishery waste, as an adsorbent for removal of Cd(II), Cu(II) and Pb(II) ions from contaminated water was evaluated by characterization and adsorption studies. The characterization study was performed using Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray (EDX) Spectroscopy and Fourier Transform Infrared (FTIR) Spectroscopy techniques. The effects of solution pH (pH 1.0 to 6.0), adsorbent dosage (0.125 to 0.750 g) and initial adsorbate concentration (10 to 200 mg/L) on adsorption capacity of lala clam shell were studied. The capability of lala clam shell to remove metal ions from aqueous solution was assessed in both single- and mix-metal systems. The adsorption equilibrium data were fitted to Freundlich and Langmuir isotherm models. At an optimum solution pH of 6.0 and initial metal ion concentration of 200 mg/L, the maximum adsorption capacity (Qmax) values of Cd(II), Cu(II) and.....

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