Fungal assist microalgal cultivation is getting substantial considerations due to the highly efficiency of bioflocculation process without demanded of using chemicals and little bit energy input. Therefore, Fungi pelletization-assisted microalgal cultivation were applied for improving algal harvesting process and nutrient recovery as step wise for wastewater treatment. Two strains of marine microalgae (Nannochloropsis salina and Chlorella salina) and three species of marine fungi (Penicillium chrysogenum, Aspergillus niger and Aspergillus fumigatus) were implied to investigate the effect of fungi-algae pelletization process on wastewater recovery. After 48 hour of cultivation, the highest flocculation efficiency (98. 9%) was recorded by A. fumigatus assist C. salina, while the lowest percentage (85. 9%) recorded by A. niger assist N. Salina. The highest nutrient removal percentage was for nitrite by A. niger assist C. salina /tap water (98. 4%) followed by phosphate A. fumigates assist N. salina/sea and tap water (90. 9%), then ammonia by A. fumigates assist N. salina/seawater (89. 5%). The bioflocculation process is a promising for algal harvesting techniques and wastewater nutrient recovery.

Pond-grown microalgae have been considered as feedstocks for production of biodiesel. Various natural habitats and man-made environments can be exploited to cultivate microalgae without utilizing arable land which is already decreasing due to urbanization and industrial development. Suitable temperature, solar illumination and availability of phosphorus and nitrogen-rich organic wastes result in algal blooms in stagnant water and river bank’s associated pools in many regions including Pakistan. However, for practical application different land areas and effluents of varying natural and man-influenced environments are to be screened for promoting growth and fat-rich body composition of microalgal biomass. Lessons from well-established science of continuous culturing of bacteria can be applied for the open systems with provisions of semi-controlled physico-chemical conditions. In situ microalgal cultivation ponds may be declared mandatory for suitable industries and they can also be cultivated along the banks of rivers. Such efforts will lead to the production of biodiesel, environmental management of effluents and usage of the oil extracted/defatted algal biomass as animal feed supplement. The triad of biofuel production, bioremediation of suitable effluents and provision of animal feed/its supplement would obviously achieve economical feasibility. Different prospects of microalgal cultivation in different localities of Pakistan are discussed with reference to profitable investments.

Microalgae have been utilized as eco-friendly bioremediation agents in aquaculture wastewater with concomitant biomass production. However, growth, bioremediation efficiency, and the nutritional components of the resulting biomass still need assessment to evaluate their potential as bioremediation agents, growth performance, and fertilizer sources. This study evaluated five microalgae, namely, Tetraselmis tetrathele, Nannochlorum sp., Chaetoceros calcitrans, Isochrysis galbana, and Thalassiosira sp., grown using milkfish wastewater. Specific growth rate (SGR), biomass productivity and concentration, nutrient removal efficiency, and the nutritional components of the biomass were analyzed as bases for determination. Results showed that Nannochlorum sp. and Isochrysis galbana had the highest SGR of 0.263 and 0.255 μ day-1, respectively. However, due to their larger size, Tetraselmis tetrathele and Thalassiosira sp. had the highest biomass productivity and concentrations of 0.075 and 0.065 g L-1 day-1 and of 0.933 and 0.879 g L-1, respectively. Tetraselmis tetrathele is best in removing N and P, achieving removal efficiency of 98.24% and 98.87% for NH3-N and NO2-N, respectively, while 72.50% for P. Tetraselmis tetrathele and Thalassiosira sp. had significantly higher N, with no significant difference among microalgae for P. At the same time, Thalassiosira sp. was significantly higher in K. There was no significant difference among algae in terms of Cu, while Tetraselmis tetrathele and Thalassiosira sp. were significantly higher in Zn, Tetraselmis tetrathele, Nannochlorum sp., and Isochrysis galbana for Mn, and Thalassiosira sp. for Fe. Results indicate that Tetraselmis tetrathele emerged as the most efficient species for bioremediating aquaculture wastewater compared to the other microalgae. While Tetraselmis tetrathele and Thalassiosira sp. exhibited high biomass productivity and potential as fertilizer sources, they outperformed the other microalgae.

Microalgae have garnered significant attention as a promising source for biodiesel production due to their rapid growth, high lipid content, and minimal resource requirements. This study delves into the forefront of microalgal biofuel research by investigating emerging co-cultivation strategies aimed at optimizing biomass production for biodiesel synthesis. Through a nuanced exploration of diverse microalgal strains, this work pioneers innovative co-cultivation techniques designed to enhance synergies between different species, thus maximizing overall productivity. Microalgae are excellent options for the production of biodiesel since they have high lipid content and grow quickly. Nonetheless, difficulties in maximizing lipid and biomass production have led the technological advancement microalgal productivity using photobioreactors, closed systems and monitoring and genetic Engineering The article delves into the impact of Co-cultivation on microalgal growth such as improved Biomass production, enhanced lipid content and quality and nutrient utilization and recycling.

Introduction: Mixotrophic microalgae systems have great potential for bioenergy production and wastewater treatment. Anaerobic-treated wastewater supplemented with carbon can improve biomass yield and quality, as it presents low carbon content. Alternative carbon sources in microalgae cultivation, such as glycerol, are essential for minimizing the economic and environmental impacts caused by biomass production, and improving the profile of fatty acids. This study aimed to increase biomass production and the lipid content with glycerol as the carbon source for microalgae cultivation from sanitary wastewater. Materials and Methods: The microalgae behavior in the wastewater was pilot tested using glycerol supplementation at 7. 5, 10. 5, and 12. 5 g L-1. Results: In all the experiments with sanitary wastewater, the microalgae production presented Chlorella sp. as the predominant species. The best biomass (3. 78 ±,1. 12 g L-1) and lipid (35. 67 ±,0. 80%) yields were found at 12. 5 and 10. 5 g L-1 of glycerol, respectively. Conclusion: The microalgae produced more lipids with glycerol supplementation. An attractive profile for biodiesel was found regarding the fatty acids in the biomass.