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The functional composites of activated carbon black-titanium dioxide (ACB-TiO2) with antibacterial-photocatalytic properties have been properly synthesized in this research using ultrasonic of 40 kHz, 2´50 W at 50oC for 10, 20, and 30 minutes agitation time. This research aimed to enhance titanium dioxide's antibacterial and photocatalytic properties (TiO2) using activated carbon black (ACB) particles forming ACB-TiO2 composites. The antibacterial properties of the materials were evaluated based on their capability of inhibiting Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) bacteria cells growth, while the photocatalytic properties of them were evaluated based on their capability of degrading methyl orange dye molecules under ultraviolet (UV) light exposure. It is conclusively known that the ACB-TiO2 composites can be synthesized from the activated carbon black (ACB) and titanium dioxide (TiO2) of about 164 nm and 547 nm in their particle size respectively employed ultrasonic agitations for the various time. All of the produced ACB-TiO2 composites could inhibit the bacterial cell growth and also could decompose the methyl orange molecules with the best was that synthesized using 30 minutes ultrasonic agitation time.

Glycerol is a by-product produced from biodiesel production through the transesterification process. The excessive amount of glycerol generated during this process may become an environmental problem since it cannot be disposed on the environment. One of the possible applications is its use in biofilm production as a plasticizer. This research aims to characterize the physicochemical properties of biofilm produced from Dioscorea hispida (Ubi Gadong) starch with a different formulation of glycerol extracted from recycling cooking oil. Dioscorea hispida starch has shown great potential as a major component in bioplastic production due to its faster degradation rate, while glycerol acted as a plasticizer. The contact angle, water absorption, water content, and degradation rate of biofilm were also studied. Biofilm with the highest ratio of glycerol content showed the highest water absorption, which achieved 75.75%, and the biodegradable rate of biofilm was 97.99% on day 3. The lowest glycerol content in biofilm showed the lowest contact angle and completely biodegradation after five days buried in the soil.

Microcrystalline cellulose (MCC) from bamboo is a natural biodegradable polymer that can be applied as barrier materials in the form of films. Bamboo contributes to 90% of the total mass of the dry weight comprised of cellulose, hemicellulose, and lignin. In this study, Gigantochloaalbociliata (Buluh Madu) was chosen due to the fast-growing species, cheaper and abundance in Malaysia. This bamboo was undergone Kraft pulping process to get the pure cellulose and then continued with the acid hydrolysis process to produce microcrystalline cellulose (MCC). In this study, thin-film PLA/PBAT reinforced with microcrystalline cellulose derived from Gigantochloaalbociliata were produced. PLA is high in strength and ductility, but it is brittle while PBAT is elastic and strong. Therefore, PBAT is a great candidate for PLA hardness. The thin film was characterized with XRD, DSC and TGA to compare the thin film from microcrystalline cellulose derived from bamboo (B-MCC) with the commercial microcrystalline cellulose (C-MCC). The C-MCC was used as reference material. From the results, B-MCC has the same crystallinity index as C-MCC with a value of 51.3%. It can be concluded that B-MCC is can be one of the alternatives for the microcrystalline cellulose due to the abundance of bamboo as fast-growing species. Furthermore, it exists naturally, has low cost, is biodegradable, is a low-density compound, and fits best in the field of renewability.