Indigenous microalgae (KR349061) were isolated from the agro-industrial wastewater and screened in order to determine their potential for biomass and biodiesel sources. Bold’s Basal Medium was used to isolate the colonies from sample. The nutrient contents were altered in order to optimize the growth of the microalgae. The isolates were identified based on the morphology and microscopic appearance of the isolated colonies. It was seen that the isolates comprised of several common green microalgae and cyanobacteria, among which the ideal candidate was selected and further investigated. Lipid content was determined for the strains that showed rapid growth. The results showed that Chlamydomonas incerta achieved highest lipid content of biomass (42.6%) after 2 d, also highest lipid productivity of 0.197 mg/L/d was observed when the initial COD concentration was 500 mg/L. C. incerta also showed higher growth rate and higher amount of lipid was examined for its potential as sustainable biodiesel feedstock along with its higher biomass yield.

Water hyacinth (Eichhornia crassipes) was used to determine their efficiency in treating domestic wastewater. The wastewater sample was collected from the stabilization pond located at the University Technology Malaysia, and was determined for different parameters like pH, chemical oxygen demand (COD), phosphate ( ), nitrate ( ), ammonical nitrogen (NH₃), total organic carbon (TOC), and biomass growth rate. A batch system fabrication was set up which contained 1 kg of fresh plant (E. crassipes) and the experiment was run for 21 d in order to correlate nutrient uptake and biomass growth rate. All the parameters were determined according to APHA standard and compared with Interim National Water Quality Standards, Malaysia (INWQS).The phytoremediation treatment of wastewater with water hyacinth showed pH ranging in between 5.3 and 6.3. Moreover, a considerable percentage of reduction was observed in most of the parameters used which included COD, TOC, and NH₃, when compared to the INWQS standard. The capability of these plants in removing nutrients present in the wastewater was successfully demonstrated during this study. The optimum growth period for water hyacinth was found to be 18 d and it is recommended that these aquatic macrophytes should be removed from the water bodies for providing efficient water purification.

The potential use of crushed cockle shells (Anadara granosa) for treating polluted river water in the fabricated column model was investigated along with the determination of the optimum amount of A. granosa used in the fabricated column model based on the results obtained from the series of jar test experiments performed during the study. The result shows that the crushed cockle shell could reduce chemical oxygen demand with the adsorption capacity of 5.3191 mg g⁻¹. Moreover, based on adsorption isotherm, it is shown that the adsorption data best fitted for Freundlich (R²= 0.9798) when compared to Langmuir isotherm (R²= 0.5737). The breakthrough curves plotted based on the data obtained from fabricated column model experiment indicates that the exhaustion time of crushed cockle shell was on the third day. The linearization of breakthrough curves based on Thomas model, Yoon–Nelson model, and Adam–Bohart model, shows that the curves best fitted with Adam–Bohart model, since the value of R² was higher compared to the other models tested during the experiment.