The impact of using recycled culture medium to grow Chlorella vulgaris in a sequential flow system: Evaluation on growth, carbon removal, and biochemical compositions

Excessive of carbon dioxide (CO2) emission and water pollution have been identified as the two primary challenges to humans and environment. Hence, biological carbon sequestration by microalgae is recommended as an environmentally friendly approach to capture and convert this CO2 into value-added products. However, research related to the development of efficient system to concurrently overcome low CO2 solubility in water and reduction of water footprint in microalgae cultivation is still limited in the literature. In this study, the CO2 capture by Chlorella vulgaris in a recycled cultivation medium was exploited using a sequential flow photobioreactor system. The study revealed that nutrient replenished recycled medium did not significantly affect the growth performance and lipid content of C. vulgaris. It was also observed that the CO2 capture efficiency and protein content were gradually increased from the first (SFB-RWN1) to the third (SFB-RWN3) cycle of cultivation due to the increment of carbon and nitrogen content in the microalgae cell. Besides, the lipid profile of C. vulgaris cultivated in the recycled medium comprised of high concentration of saturated (up to 32.41%) and polyunsaturated (up to 43.21%) fatty acid methyl ester (FAME). The present study suggested that growing C. vulgaris in a recycled medium is a feasible solution to fix CO2 from the atmosphere and help to reduce water footprint in the microalgae cultivation system

Isolation and characterization of Nanocrystalline cellulose based nanobiocomposite from oil palm biomass with potential application in packaging.

Bionanocomposite is one of the remarkable achievements of nanotechnology in material science to replace conventional non-biodegradable petroleum based plastics for packaging applications. In generaL bionanocomposites are made up of biodegradable polymers (biopolymers) and bio based reinforcing material in the size range of I 0 - I 00 nm in one or more dimensions. Bio based materials could provide a solution for petroleum shortage and waste management problems. One of the potential reinforcing agents is agro industrial biowastcs such as oil palm empty truit bunch tiber "hich has highest composition of cellulose as compared to other fibers. This stud: inwstigate' the effectiveness of nanocrysta\line cellulose (NCC) derived from oil palm empt) fruit bunch (OPEFB) fibers as reinforcement in order to improve the mechanicaL thermaL morphological and barrier properties of bionanocomposite materials. The nanocrystalline cellulose was extracted from oil palm empty fruit bunch fibers through a series of chemical treatment

Algae biorefinery: Review on a broad spectrum of downstream processes and products

Algae biomass comprises variety of biochemicals components such as carbohydrates, lipids and protein, which make them a feasible feedstock for biofuel production. However, high production cost mainly due to algae cultivation remains the main challenge in commercializing algae biofuels. Hence, extraction of other high value-added bioproducts from algae biomass is necessary to enhance the economic feasibility of algae biofuel production. This paper is aims to deliberate the recent developments of conventional technologies for algae biofuels production, such as biochemical and chemical conversion pathways, and extraction of a variety of bioproducts from algae biomass for various potential applications. Besides, life cycle evaluation studies on microalgae biorefinery are presented, focusing on case studies for various cultivation techniques, culture medium, harvesting, and dewatering techniques along with biofuel and bioenergy production pathways. Overall, the algae biorefinery provides new opportunities for valorisation of algae biomass for multiple products synthesis

Decolourization of chicken compost derived liquid fertilizer via synergic ultraviolet (UV) irradiation and ozonation for enhanced microalgae cultivation

Compost-derived liquid fertilizers are uncostly and nutrient-enriched; however, its dark brown appearance limits light uptake of microalgae during autotrophic cultivation. Here, integrated UV irradiation/ozonation pretreatment was employed to decolourize the compost solution prior to microalgae cultivation. Aforesaid pretreatment could accomplish 16.52 % (8 h) or 40.88 % (24 h) decolorization efficiency by using optimal parameters (initial pH of 12, ozone concentration of 30 mg/L, and ozone flow rate of 3 L/min. Compared to untreated compost solution, microalgae Chlorella vulgaris grew better in the medium supplemented with decolourized compost solution (after 24 h UV irradiation/ozonation). For the autotrophic cultivation of C. vulgaris with 10 vol.% compost solution, UV irradiation/ozonation pretreatment eventually increases the microalgae dry weight, specific growth rate, and biomass productivity from 0.58 g/L, 0.14 d-1, and 0.040 g/(L·d) to 0.88 g/L, 0.19 d-1, and 0.065 g/(L·d), respectively. Furthermore, the lipid content of microalgae has been increased by 33.33% with pretreatment of compost solution