Advanced Materials Research Vol. 1113

Abstract: Epipremnum pinnatum is a vegetative, type of vines and climbing plant that can be found in a semitropical and tropical country in South East Asia and Asian region. It has been used as folk remedies due to its medicinal properties and capability in enhancing the immune system. However, limited scientific data are present to support this claim. Thus, the present study was focused on the determination of phytochemical properties of the extract E. pinnatum and the effect on the pancreatic lipase inhibitory activities. Phytochemical of E. pinnatum was extracted using supercritical carbon dioxide (CO₂) at 6000 psi and 40°C. The extracted oil was analyzed using Follin- Ciocalteu method to determine the phenolic components and followed by gas chromatography analysis. Chicken pancreas was used to investigate pancreatic lipase inhibitory activities of the extracted E.pinnatum. The results indicated that extract E.pinnatum could inhibit the chicken pancreatic lipase activity and based on the analysis obtained, the amount of lipase activity inhibited was 74 % by using 48 μg/ml of extract E.pinnatum.

Abstract: In Malaysia, the amount of electronic waste (e-waste) generated in 2008 was stated to be around 688,000 metric tonnes and was forecasted to increase to 1.11 million metric tonnes in the year 2020 [1]. Typical e-waste contains some elements of precious metal, which is mainly generated from the result of the revolution of computer technology. Currently, the most common technique being practiced to recover gold from e-waste is through cyanide leaching system and subsequent gold recovery techniques which may include electrodeposition. However, due to toxicity of the harmful cyanide, a non-cyanide extraction route is now becoming a necessity to minimize safety and environmental issues. In order to maximize the efficiency and safety of gold recovery from e-waste, a non-cyanide route using a reactor based on electrodeposition technique has been proposed. This paper explains the conceptual reactor design which combines the pressure leaching process of gold from e-waste and the gold recovery using electrodeposition via a non-cyanide route as a safer and environmental friendly process in recovering gold from e-waste.

Abstract: One of the most precious plants on earth is genus Aquilaria which able to produce agarwood . Under this genus, there are more 15 species around the world where the population is dense in Asia region. Four main Aquilaria spp will be discussed; (1) Aquilaria Sinensis, (2) Aquilaria Malaccensis, (3) Aquilaria Crassna and (4) Aquilaria Subintegra which currently being researched for health applications. The review helped researcher to have the brief ideas on the pharmacological effects of agarwood.

Abstract: Noise has detrimental effects on human lives and it is a nuisance to the environment. As many of the available sound reduction materials in the current market are hazardous, there are demands for alternative sustainable materials to reduce the noise problem. Therefore, the aim of this research is to study the potential of using an agricultural waste as sound absorption panel. For the purpose of this study, the combination of two materials was under studied; rice husks and sugarcane baggase. There were two main objective of the research; first is to develop absorption panels from the combination of rice husks and sugarcane baggase at different percentage of mixture. Second objective is to identify the absorption rate of the panels. The study encompasses the fabrication of the sustainable sound panels using the rice husk and sugarcane fibre and bond using Phenol formaldehyde (PF). Five panels of sized 12 inch x 12 inch and 12 mm thick were fabricated. The absorption coefficient of the samples was done at the acoustic lab, Faculty of Engineering & Build Environment, Universiti Kebangsaan Malaysia (UKM), Bangi. The panels were tested using an impedance tube. The procedure of the test was carried out in accordance with ISO 10534-2:1998 standards. Based on the results, sample 1 gave the highest absorption coefficient compared to sample 2, 3, 4 and 5. It can be concluded that the acoustic panel made from a mixture of 100% rice husks had higher absorption co-efficient compared to the performance of the other samples given the fact that the characteristic of the rice husks which has air gap in every single piece of rice husk. The spongy properties of the sample 1 panel has created many void spaces which encouraged more sound absorption capability due to the porous surface of the panel. Sound absorption is very much affected by the availability of porosity level of the panel. Thus, further studies on other potential materials from waste should be conducted.Keywords. Noise, Agriculture waste, sound, absorption panels, absorption co-efficient

Abstract: The phenomenon of rubber consumption in Malaysia has been increased parallel with the world demand. Hence, it is necessary for the cultivators to gain some knowledge for differentiating various rubber tree clone breed which may give them high latex yield after 5 years or more of planting. This paper discusses the identification of several rubber tree clones breed based on the best percentage of the reflectance wavelength obtained from the respected latex. In this work, there were three selected rubber tree clones which are RRIM 2025, PB 355 and PB 350 suggested by Rubber Research Institute of Malaysia (RRIM) will undergo a preliminary analysis on the significant information of spectrum properties acquired from the latex. A hundred of latex samples have been collected from each clone and extracted the optical measurements of the primary color spectrum (Red, Green and Blue) using spectrometer. The next step is to analyze the acquired information based on its reflectance wavelength with respect to clones and at the end it will be evaluated statistically. As a result, there were two out of three clones could be discriminated between each other with refer to the green wavelength (573nm).

Abstract: An overview on molecular structure of adsorbed additive orientates at particle interface in order to understand the ability of dispersants to affect dispersion behaviour is presented. With a wide range of molecular structures, adsorbed additive molecule generates different conformational molecular structure (CMS) combined with interaction of a range of forces occurring with the adsorbed additive molecules and between the adsorbed additive molecules; hence change the surface chemistry of particles in the dispersion.

Abstract: This study investigates the antioxidant activity and total phenolic content on different parts of Garcinia mangostana which are pericarp, leaf, fruit, and seed. 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was used to determine the antioxidant activity and the total phenolic content was determined by Folin-Ciocalteu method. Response surface method (RSM) was used to determine the effect of the two extraction variables: extraction time (30-120 minutes) and extraction temperature (30-50°C) on yield of total phenolic content and antioxidant activity of different parts of Garcinia mangostana. The significant factors on each experimental design response were identified from the analysis of variance (ANOVA). The best condition for total phenolic content of different parts of Garcinia mangostana was chosen based on the desirability obtained by using extraction temperature of 30°C and extraction time of 60.09 minutes, which resulted in 0.0274 mg GAE/g of total phenolic content in pericarp, 0.2501 mg GAE/g of total phenolic content in leaf, 0.0202 mg GAE/g of total phenolic content in fruit, and 0.0198 mg GAE/g of total phenolic content in seed of Garcinia mangostana. Under this conditions, it was found that the antioxidant activity of pericarp, leaf, fruit, and seed of Garcinia mangostana were 89.45%, 86.58%, 93.33%, and 78.80% of radical scavenging activity, respectively.

Abstract: The objective of this study is to investigate the ability of Elaeis guineensis fruit fiber or known as oil palm mesocarp fiber (OPMF) to adsorb nickel from aqueous solution. As one of the major oil palm producer, Malaysia has abundantly oil palm waste that potentially be used as biosorbent. Limited studies used OPMF as biosorbent to remove nickel, thus it was used in this study. The effects of pH, initial metal concentration and contact time on nickel uptake were studied. The OPMF was soaked in nickel nitrate aqueous solution and the Ni-loaded OPMF being digested to analyse the nickel concentration by using ICP-OES. The adsorption was investigated in the pH range of 2.0-8.0 and the optimum pH for nickel removal was found to be 7.0. The contact time was varied between 5 to 120 mins and the nickel adsorption was found to achieve equilibrium in a very short time (i.e.<5 mins). The percentage of nickel removal decreased from 3.3 to 1.7 % with increasing nickel concentration from 505 to 1683 mg/L. The adsorption isotherm was fitted well using Langmuir model with correlation coefficient, R² of 0.98. The kinetic studies showed that the pseudo-second order model is the best model with the correlation coefficients of > 0.99 for all concentrations. Overall, the adsorption of nickel by OPMF gave positive results and the used of OPMF as biosorbent has great potential to be applied in the future.

Abstract: Paper wastes accumulating in the environment are posing an ever increasing ecological threat. This study aimed to isolate soil bacteria closely associated with the bacteria degrading waste paper. A total of six soil samples were collected from dumped soil hostel garden at Universiti Teknologi MARA, Shah Alam. Bacillus, Aspergillus and Micrococcus species were found to be the most widely distributed on the entire sample taken. Six cultures were screened for the ability to degrade cellulose. Bacillus was identified as only bacteria isolated that can degrade paper at highest production of glucose compared to others. The efficacy of microbes in the degradation of paper was analyzed in broth culture fermentation within 7 days incubation. This work reveals that Bacillus subtilis, Bacillus spp and Micrococcus spp posses great potential to degrade paper. In contrast, Acinetobacter spp react very slowly in degrading the waste.

Abstract: This paper reported on the characterization of the Automotive Paint Sludge (APS) via several characterisation technique. It is an essential to search the physical and chemical characterization of the automotive paint sludge sample for further microwave assisted pyrolysis experiment for chemical and energy recovery from APS. APS contains about 2.9%, 2.4%, 75.9% and 3.2% of ash, moisture, volatile matter and fixed carbon content respectively. Both wet and dried APS samples show similar FTIR peak at the hydrocarbon region while wet sample have high water content. Meanwhile zero moisture (ZM) sample loss almost 90% of its content on the hydrocarbon. This shows that wet automotive paint sludge samples can be used in the microwave pyrolyzer without any pretreatment and the water can act as an absorbance to microwave radiation. While APS itself contains about 22.6 MJkg^-1 of energy. Furthermore, melting temperature of automotive paint sludge are in the range of 260 °C to 500 °C with the enthalpy in the range of 40 J/g to 300 J/g. Chemical composition of APS for all three conditions can be described as C₃₈H₁₀N₉S, C₁₀₂H₉N₂₁S and C₈₅H₈N₂₁S for wet sample, open air dry sample and zero moisture sample respectively.