This study reports the biodiversity of thermophilic cellulolytic bacterial strains that present in the north Malaysian mangrove ecosystem. Soil samples were collected at the four most northern state of Malaysia (Perak, Pulau Pinang, Kedah and Perlis). The samples obtained were first enriched in nutrient broth at 45°C and 55°C prior culturing in the carboxymethylcellulose (CMC) agar medium. Repeated streaking was performed on the CMC agar to obtain a pure culture of each isolate prior subjecting it to hydrolysis capacity testing. The isolates that showing the cellulolytic zone (halozone) were sent for 16S rRNA sequencing. Total seven isolates (two from Perak, three from Kedah, another two were from Perlis and Penang each) showed halozone. The isolate (KFX-40) from Kedah exhibited highest halozone of 3.42 ± 0.58, meanwhile, the one obtained from Perak (AFZ-0) showed the lowest hydrolysis capacity (2.61 ± 0.10). Based on 16S rRNA sequencing results, 5 isolates (AFY-40, AFZ-0, KFX-40, RFY-20, and PFX-40) were determined to be Anoxybacillus sp . The other two isolates were identified as Bacillus subtilis (KFY-40) and Paenibacillus dendritiformis (KFX-0). Based on growth curve, doubling time of Anoxybacillus sp . UniMAP-KB06 was calculated to be 32.3 min. Optimal cellulose hydrolysis temperature and pH of this strain were determined to be 55°C and 6.0 respectively. Addition of Mg 2+ and Ca 2+ were found to enhance the cellulase activity while Fe 3+ acted as an enzyme inhibitor.

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In recent years, the biotechnological use of xylanases has grown remarkably. Xylanase is a hydrolytic enzyme with a broad industrial application. In specific, xylanase can convert xylan into xylose, a fermentable sugar source for secondary bioethanol production. The objective on this study is to investigate the significance of different parameter effects for an efficient xylanase production from Aspergillus niger (A. niger). In this study, four factors: incubation temperature, medium pH, incubation time, and agitation speed were screened by performing One-factor-at-a-time (OFAT) analysis. Xylanase production with the maximal enzyme activity was successfully obtained from OFAT analysis under condition of 32°C, pH 5.0, 5 days, and 150 rpm.

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Membrane application is widespread in water filtration to remove natural organic matter (NOM), especially humic acid. However, there is a significant concern in membrane filtration, which is fouling, which will cause a reduction in the membrane life span, a high energy requirement, and a loss in product quality. Therefore, the effect of a TiO2/PES mixed matrix membrane on different concentrations of TiO2 photocatalyst and different durations of UV irradiation was studied in removing humic acid to determine the anti-fouling and self-cleaning effects. The TiO2 photocatalyst and TiO2/PES mixed matrix membrane synthesised were characterised using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray powder diffraction (XRD), scanning electron microscope (SEM), contact angle, and porosity. The performances of TiO2/PES membranes of 0 wt.%, 1 wt.%, 3 wt.%, and 5 wt.% were evaluated via a cross-flow filtration system regarding anti-fouling and self-cleaning effects. After that, all the membranes were irradiated under UV for either 2, 10, or 20 min. A TiO2/PES mixed matrix membrane of 3 wt.% was proved to have the best anti-fouling and self-cleaning effect with improved hydrophilicity. The optimum duration for UV irradiation of the TiO2/PES mixed matrix membrane was 20 min. Furthermore, the fouling behaviour of mixed matrix membranes was fitted to the intermediate blocking model. Adding TiO2 photocatalyst into the PES membrane enhanced the anti-fouling and self-cleaning properties.