Chlorococcum humicola (Nageli) Rabenhorst as a Renewable Source of Bioproducts and Biofuel

Abstract

Among the diverse new generation biomass yielding species, green algae are the most promising organisms. Compared to biomass production of other organisms, production of algae is less laborious, quite fast, and more economical. Moreover, eutrophicated waters get naturally purified in the cultivation process of algae. Algal biomass from monoculture of specific species, which are rich in carbohydrates, proteins and lipids, is considered a good source of diverse bio-products and feed-stock for food, feeds and bio-fuels. Quantity and quality of algal biomass for specific products depend on the species and strains as well as environmental conditions of cultivation. In this connection, biomass productivity and oil-yield of a local strain of Chlorococcum humicola (Nageli) Rabenhorst was assessed in Bold's Basal Medium. Long-term storage capacity of the alga was tried by entrapping the algal cells in sodium alginate beads, which showed viability up to 14 months. Estimation of total carbohydrate, protein, lipid and chemical characterization of oil as well as the feasibility of its conversion to biodiesel revealed the industrial potential of this local strain as a source of food and biofuel. Fatty acid profiling of the extracted oil showed that 70% are mono-saturated and 12.2 % are nutritionally important polyunsaturated fatty acids. The oil could be effectively trans-esterified to methyl esters and the conversion was confirmed by FTIR spectroscopy. Further standardization of the mass production of the alga in natural environmental conditions for biomass and oil is progressing to optimize its value as globally competent food, nutraceutical and biofuel resource.

Alginate Beads Utilization for Long-Term Storage of Microalgal Isolates

“…The use of sodium alginate aided in preparing the artificial seeds of the microalgae. The preparation of 3% sodium alginate ran in the Chu 13 medium (free of CaCl 2 .2H 2 O) with continuous stirring at 60 ᵒC in a water bath, then, adjusting the pH to 5.8, sterilizing the mixture continued in an autoclave for 20 min, based on the methodology by Santhoshkumar et al (2016) and Al-Mula (2022). Taking 5 ml from each pure liquid culture of microalgae at the age of two weeks underwent centrifuging with added speed and condition of centrifugation.…”

“…Five beads underwent cultivation on 50 ml of Chu 13 medium for 20 days. The number of cells counted growing in the medium per 1 ml received evaluation for their vitality after each incubation period (Santhoshkumar et al, 2016).…”

“…The number of algal cells under study calculated over the course of 18 months (2.5-3.5×10 6 cell ml -1 ). preparation of alginate beads (Chu 13), as compared with the study of Santhoshkumar et al ( 2016), who observed the stability in the number of growing cells of the alga Chlo. humicola during a bioassay of alginate beads for 14 months using a BBM medium.…”

“…In stock culture and long-term storage of algae seeds for producing biomass and secondary metabolites, the recommended extended preservation of algae cultures is in sodium alginate beads form. Such a method of algae preservation can also aid wastewater treatment and heavy metal removal (Santhoshkumar et al, 2016).…”

“…Encapsulating the filamentous cyanobacteria Pseudanabaena galeata cells in sodium alginate gained storing in the refrigerator for 14-18 months. Santhoshkumar et al (2016) indicated the possibility of lengthened storage of the alga Chlorococcum humicola by regulating algae cells in sodium alginate granules, which showed viability for up to 14 months.…”