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The contamination of the hexavalent chromium [Cr(VI)] in the aquatic ecosystem poses environmental concerns due to its portability and highly poisonous quality. The implementation of magnetic bio-adsorbent has received immense...

Biodegradable packing materials with antimicrobial properties have been a concern for years because of its positive environmental implications. The present work aimed to develop the formulation of hydroxyethyl cellulose (HEC)/wheat-starch based film in which the active compound, thymol (0.5, 1, 1.5, 2, and 2.5% w/w) were incorporated into the polymeric material. Solution casting method was used for the film preparation while thymol was incorporated prior to casting. The physical and chemical properties of the developed film were determined. SEM was found to have a smooth and homogeneous with a small amount of thymol which grows coarser with 1.5% or higher thymol content. FTIR was used to find the chemical property of the film and suggested that the carbonyl functional group was unchanged in the film, however, -OH groups increased substantially with increased amount of thymol. Thermal properties were profiled through thermogravimetric analysis and differential scanning calorimeter where the AM film containing 1.5% (w/v) of thymol shows the highest thermal stability and decomposes less in comparison to other samples. The inhibitory capability of the film was tested against a list of microbial contamination and was found to successfully inhibit the growth of selected gram positive and gram negative bacteria in a wide range of studied concentration. The mechanical properties of the films were improved by 60.3% with an optimum tensile strength at thymol concentration of 1.5% w/w. It can be concluded that the film properties are retained chemically whereas mechanical properties, strength, flexibility and function of the film are being enhanced remarkably by the incorporation of thymol.

Cellulose is a biopolymer that may be derived from a variety of agricultural wastes such as rice husks, wheat straw, banana, and so on. Cellulose fibril that is reduced in size, often known as nanocellulose (NC), is a bio-based polymer with nanometer-scale widths with a variety of unique properties. The use of NC as a reinforcing material for nanocomposites has become a popular research issue. This research paper focuses on the production of banana pseudostem cellulose nanofiber. Nano-sized fiber was obtained from banana pseudostem through several processes, namely, grinding, sieving, pre-treatment, bleaching, and acid hydrolysis. The product yield was found to be 40.5% and 21.8% for Musa acuminata and Musa balbisiana, respectively, by the weight of the raw fiber. The reduction in weight was due to the removal of hemicellulose and lignin during processing. Transmission electron microscopy (TEM) analysis showed that the average fiber size decreased from 180 µm to 80.3 ± 21.3 nm. Finally, FTIR analysis showed that the fibers experienced chemical changes after the treatment processes.

The presence of glyceryl esters (GE) and 3-monochloropropane-1,2-diol esters (3-MCPDE) in refined, bleached, and deodorized (RBD) palm oil is severely concerning to the palm oil consumer. In the present study, the influence of the phosphoric acid degumming process on the formation of GE and 3-MCDE and in the RBD palm oil was determined with varying the acid dose (0.03–0.06 wt%), temperature (70–100 °C), and reaction time (15–45 min). The experimental conditions of the acid degumming process were designed following the central composite design of experiments, and they were optimized using Response Surface Methodology (RSM) based on the minimal formation of GE and 3-MCDE in the RBD palm oil. The optimal experimental conditions of the acid degumming process were a reaction time of 30 min, phosphoric acid concentration of 0.06 wt%, and temperature of 90 °C. Under these experimental conditions, the minimal GE and 3-MCDE formation in RBD palm oil were determined to be 0.61 mg/kg and 0.59 mg/kg; respectively. Several analytical methods were employed to determine RBD palm oil quality, including color, phosphorus, free fatty acids (FFAs), peroxide values, and fatty acid properties. It was found that the phosphoric acid degumming of CPO effectively removed the phosphorus and hydroperoxide content without conceding the quality of palm oil.

In recent years, the potential of agricultural wastes has received increasing attention from academia and industry. The aim has been to identify strategies for the conversion of low-value wastes into new materials and other value-added products. Cellulose is a naturally abundant polymer that is readily available in various agricultural wastes. It is a linear polymer consisting of β-D-glucopyranose units (disaccharides) joined by glycosidic β-1,4 bonds. Nanoparticles can be extracted from cellulose fibers using a top-down mechanically or chemically treatment. Cellulose nanomaterials have generated significant interest due to their intrinsic properties such as large surface-to-volume ratios, high tensile strength, stiffness, and flexibility in addition to good dynamic mechanical, electrical, and thermal properties. The use of nanocellulose for reinforcement in matrices improves thermo-mechanical properties, decreases the sensitivity of polymers to water, and preserves biodegradability. The mixing of nanocellulose with polysaccharides improves mechanical properties. Nano-sized cellulose fibers possess unique physical, chemical, and morphological characteristics. Hence, nano-sized cellulose fibers are considered versatile materials for addition to polymers, and application in high gas barriers and packaging materials. Other uses include electronic devices, foods, medicine, cosmetics, and health care. This chapter focuses on the cellulose nanofibers attained from banana, pineapple and corn-based agricultural wastes.

Bioethanol/biodiesel are deemed a highly suitable alternative to conventional fuels in the near future due to their versatility in production techniques and operability. This paper examines the engine performance and possible scope of improvement in direct injection engines powered by biofuel blends. The obtained outcomes from this review are mainly focused on three distinguished fuel properties: fuel feasibility, emissions, and engine performance. Critical analysis of these factors is followed by the highlighting of the possible scope of improvement. This review indicates that biofuels perform best with additives or as an additive when used with traditional petroleum fuels. Research analysis indicates that biodiesels show significant improvement in ignition delay due to higher oxygen content compared with traditional petroleum fuels and produce lower emission of pollutant gas. However, engines have shown a decrease in performance regarding power output, torque, and fuel efficiency. The suggested improvement to counter these issues include the addition of nanoparticles, exhaust gas recirculation, ethanol/methanol fumigation, and introduction of various methyl esters into the mixture.

In this research, acrylic acid based hydrogels were prepared and impregnated with magnetic nanoparticles to enhance the efficiency of the adsorption and desorption of heavy metals. Acrylic acid and itaconic acid both are short chain and possess -COOH group, therefore, they are easily copolymerized and hydrophilic in nature. The acrylic based hydrogel acts as a support to hold the magnetic nanoparticles. Hydrogels were synthesized by using acrylic acid and itaconic acid as monomers at different monomer ratios. The magnetic particles were incorporated through in situ precipitation method by immersing into 0.25 M Fe (II) and 0.5 M Fe (III) ion aqueous solutions in the molar ratio of 1:2 for metal ions loading. The swelling behaviour of the plain acylic acid hydrogel and plain acrylic acid-co-itaconic acid hydrogel that were soaked in two different water solutions such as sea water and distilled water were studied. Result shows that plain acrylic acid-co-itaconic acid hydrogel has the tendency to swell more than plain acrylic acid hydrogel. The absorption and desorption capacity of the materials were tested in 0.1 M of cobalt and lead solutions. The materials show promising results and can be used to remove pollutants from industrial effluent.

This research aims to observe the usability of waste eggshells as a heterogeneous CaO-based catalyst to produce biodiesel via the transesterification process. The waste eggshell contains CaO and serves as a heterogeneous catalyst that can be extracted using a simple heat treatment technique. The catalyst loading used in this study were 1, 2, 3, 4, and 5 wt.%. The biodiesel yield affects the variables of the reaction, including the amount of catalyst used. According to the findings in this work, the low-weight catalyst produced more biodiesel (64% of yield) than other catalysts in the studies. Using the same CaO catalyst with a 1 wt.% catalyst, previous studies showed a biodiesel yield of 56.64%. Outcomes revealed that waste eggshells could be used as an effective catalyst to transform waste cooking oil into biodiesel, thereby significantly lowering biodiesel costs and improving product yield and fuel properties.

In addition to offering a host of health benefits, antimicrobial (AM) wheat-based packaging is a promising form of active food packaging with great economic and environmental potential. The main objective of this study is to develop a formulation of AM wheat-based film in which the active compound, lysozyme, is incorporated into the polymeric material. A solution casting method was used in the film preparation, and lysozyme was incorporated prior to casting. The resultant film is slightly less opaque, more translucent and whitish in appearance, implying that the AM film could retain similar property with the initial opacity value of the wheat-based film. The water uptake of wheat-film is reduced with the incorporation of lysozyme. The reduction in moisture content of AM film indicates a relationship between lysozyme and water molecules in the diffusion mechanism throughout the film matrices. This film helps to reduce the growth of E. coli and B. subtilis to 1.74 and 3.48 log CFU/mL, respectively, for an incubation of 48 h. FTIR analysis implies the consistency of the chemical composition and structure of the AM film compared to the control film, which indicates that the addition of lysozyme into the wheat-based film did not affect or alter the carbonyl function groups of the wheat-based film. The study will help the researcher to discover and understand wheat-based films for incorporating antimicrobial properties and to explore new matrices for further development.

Fluctuation in fossil fuel prices and the increasing awareness of environmental degradation have prompted the search for alternatives from renewable energy sources. Biodiesel is the most efficient alternative to fossil fuel substitution because it can be properly modified for current diesel engines. It is a vegetable oil-based fuel with similar properties to petroleum diesel. Generally, biodiesel is a non-toxic, biodegradable, and highly efficient alternative for fossil fuel substitution. In Malaysia, oil palm is considered as the most valuable commodity crop and gives a high economic return to the country. However, the ethical challenge of food or fuel makes palm oil not an ideal feedstock for biodiesel production. Therefore, attention is shifted to non-edible feedstock like Jatropha curcas Linnaeus (Jatropha curcas L.). It is an inedible oil-bearing crop that can be processed into biodiesel. It has a high-seed yield that could be continually produced for up to 50 years. Furthermore, its utilization will have zero impact on food sources since the oil is poisonous for human and animal consumption. However, Jatropha biodiesel is still in its preliminary phase compared to palm oil-based biodiesel in Malaysia due to a lack of research and development. Therefore, this paper emphasizes the potential of Jatropha curcas as an eco-friendly biodiesel feedstock to promote socio-economic development and meet significantly growing energy demands even though the challenges for its implementation as a national biodiesel program might be longer.

Fossil fuels bring about concerns like air pollution, rising greenhouse gas emissions due to its combustion and depletion issues. The need to more to biofuels as an alternative and renewable energy source is for a sustainable and environment for the future. This research project studies the biofuels in Malaysian perspective, the debates concerning the issues as well as the advantages and disadvantages of biofuels. The production of biofuels and comparison with fossil fuels has been done based on the social, economic and environmental context. Research is also conducted on the organizations producing biofuels in Malaysia, volume of fossil fuels are being currently replaced by biofuels, and where the projection in the next 20 years will be. After all the studies and observations are carried out, personal evaluation of further requirements or developments is made. It can be concluded that Malaysia will not be able to replace its fossil fuels with biofuels in the near future. Scopus

In this research paper, we have discussed solar energy technology types including photovoltaic cells, solar thermal and concentrated solar panels. We have analyzed methods, advantages, and drawbacks of following technology and gave our suggestions towards current need. Photovoltaic cells technology is the most sustainable technology to be applied in Sarawak. The feasibility of using solar cells in Sarawak was studied and analyzed using Photovoltaic Geographical Information System Asia (PGISA). The results showed the optimum tilt, optimum orientation and the best PV cells technology to be used and implemented. Tracking technology is vital in maximizing the insolation received by the panels. The major drawback with PV cells is its inefficiency as a lot of energy was lost in the system; for example, the inverter and cables caused huge loss of energy. In Sarawak only 25% of energy demand is covered by solar energy and remaining 75% of energy is covered by other energy sources. Solar energy in Sarawak can play a vital role though, since it is highly potential especially if it is utilized in correct way; however, startup costs and more studies are needed to be done.

Active and smart packaging is a promising form of food packaging that offers a great economical potential due to consumer demand for a packaging that accommodate a hectic way of life. An antimicrobial film with pH colour indicator (pHF) can be made by incorporating suitable antimicrobial (AM) agent and colour indicator into food package matrices whilst applying a bio switch concept to inhibit the pathogenic microorganisms and respond automatically to changes (external stimuli) in the environment. The present work aimed to study the developed formulation of hydroxyethylcellulose (HEC)/wheat-starch based pHF film in which the active compound, thymol (0.5, 1, 1.5, 2, and 2.5% w/w) and 50:50% w/w bromothymol blue and methyl red (as the colour indicator) against microbial growth. A solution casting method was used in the film preparation while thymol and colourant were incorporated prior to casting. The effect of thymol showed a range of microbial inhibition zones of 16.3 - 26.4% and 22.1 - 39.9% towards E. coli and B. subtilis, respectively. Whilst, a lower inhibition zone of 0.4 - 5.1% was demonstrated for fungus A. niger.

Candlenut oil was extracted using supercritical CO2 (SC-CO2) with an optimization of parameters, by the response surface methodology. The ground candlenut samples were treated in 2 different ways, that is, dried in either a heat oven (sample moisture content of 2.91%) or dried in a vacuum oven (sample moisture content of 1.98%), before extraction. An untreated sample (moisture content of 4.87%) was used as a control. The maximum percentage of oil was extracted from the heat-oven-dried sample (77.27%), followed by the vacuum-oven-dried sample (74.32%), and the untreated sample (70.12%). At an SC-CO2 pressure of 48.26 Mpa and 60 min of extraction time, the optimal temperatures for extraction were found to be 76.4 °C, 73.9 °C, and 70.6 °C for the untreated, heat-oven-dried, and vacuum-oven-dried samples, respectively. The heat-oven-dried sample contains the highest percentage of linoleic acid, followed by the untreated and vacuum-oven-dried samples. The antiradical activity of candlenut oil corresponded to an IC50 value of 30.37 mg/mL.

Meranti tree sawdust, an inexpensive material, is currently being investigated as an adsorbent for the removal of Cu(II) and Pb(II) ions from aqueous solutions. In this work, adsorption of Cu(II) and Pb(II) ions on Meranti tree sawdust has been studied by using batch techniques. The equilibrium adsorption level was determined to be a function of the solution of pH, contact time, and adsorbent dosage. Adsorption isotherms of Cu(II) and Pb(II) ions on adsorbents were determined and correlated with common isotherm equations such as Langmuir and Freundlich models. The thermodynamic parameters like free energy, enthalpy, and entropy changes for the adsorption of Cu(II) and Pb(II) ions have also been computed and discussed. The heat of adsorption [ΔH = 31.47 kJ/mol for Cu(II) and ΔH = 20.07 kJ/mol for Pb(II)] implied that the adsorption was endothermic in nature.

This study aims to investigate the influence of solvent on the Soxhlet extraction of omega 3 in perah seed oil. Three types of extraction solvent include hexane, hexane: methanol (90:10) and methanol: ethanol (70:30) were investigated. The concentration of extracted omega 3 was measured using Gas chromatography (GC), the colour of extracted oil was classified using colormeter and the total phenolic content (TPC) by Folin-Ciocalteau colorimetry. Based on the total yield extraction of the oil, the result shows that hexane solvent (57.5%) shows better performance compared to hexane-methanol (53.42%) and ethanol-methanol (34.52%). For the omega 3 concentration, hexane-methanol solvent provided highest yield at 1.41g ω-3/g oil followed by ethanol-methanol and hexane at 1.32 ω-3/g oil and 1.15 ω-3/g oil respectively. On the other hand, the extracted oil using hexane as extraction solvent was appeared to be lighter in colour as compared to other solvents studied. In addition, total phenolics content of perah oil was high with hexane solvent. As conclusion, the polar solvent of methanol and ethanol promoted the extraction of omega 3; however, it may cause a darker appearance of the extract as well as reducing the content of phenolic compounds.

Soxhlet extraction technique is employed for the extraction and separation of chemical constituents in the medicinalplant, Herba Leonuri. The main goal of this analytical study was focused on extracted compounds and extractionconditions themselves. Soxhlet extractions were performed at three extraction time (6h, 9h and 12h) and with twosolvents (n-hexane and methanol). A general full factorial design with two factors (extraction time and types ofextractor solvents) was implemented. The Soxhlet extraction method presented a good yield of components in extract.The study shows that methanol extracted almost double yield than n-hexane. The highest yield obtained with methanolwas 14.18%; while the highest yield obtained by n-hexane was 7.25%.The results also indicated that, for methanolextraction, the mass yield percent extracted increased with increasing length of extraction period (up to 14.18%); forn-hexane extraction, the mass yield percent extracted was not consistent with increasing length of extraction period. Theextracted oil extracted was analyzed by GC-MS. The compounds identified were vitamin E, palmitic acid and syringol.General characteristics of the Herba leonuri oils obtained by different conditions were further compared, showing thatthe composition of the Herba leonuri oil extracted by different conditions is mostly similar, whereas relative concentration of the identified compounds is apparently different. This study can be considered as the first informationon the chemical compound of Herba leonuri.