Niran Juntawong

Outdoor cultivation of Dunaliella salina KU 11 using brine and saline lake water with raceway ponds in northeastern Thailand

To evaluate the potential of algal biotechnology to replace traditional agriculture in northeastern Thailand, an open raceway cultivation system was developed to produce biomass and beta‐carotene. Dunaliella salina KU 11 isolated from local saline soil was cultured in open raceway tanks using brine and saline lake water. Grown in modified Johnsons medium (with 2–3.5 M NaCl), the algae reached a maximum cell density on the fourth day (1.8 × 106 cells mL−1). Increasing KNO3 and NaHCO3 from 0.5 and 0.043 g L−1 to 1 and 2.1 g L−1, respectively, significantly improved the yields of biomass (0.33 g L−1) and beta‐carotene (19 mg L−1). Expected profits for algal production were evaluated, and it was found that this strain was suitable for outdoor cultivation and the developing algal industry in northeastern Thailand could produce high economic benefits (at least

The Effects of Light, Temperature, and Nutrition on Growth and Pigment Accumulation of Three Dunaliella salina Strains Isolated from Saline Soil

64,120 per year per 0.16 ha).

Microalgae as an Attractive Source for Biofuel Production

Background: Developing algal industries in saline-alkali areas is necessary. However, suitable strains and optimal production conditions must be studied before widespread commercial use. Objectives: The effects of light, temperature, KNO3, and CO(NH2)2 on beta-carotene and biomass accumulation were compared and evaluated in order to provide scientific guidance for commercial algal production in northeastern Thailand. Materials and Methods: An orthogonal design was used for evaluating optimal conditions for the algal production of three candidate Dunaliella salina strains (KU XI, KU 10 and KU 31) which were isolated from saline soils and cultured in the column photobioreactor. Results: The optimal light and temperature for algae growth were 135.3 μmol m-2 s-1 and 22°C, while the conditions of 245.6 μmol m-2 s-1 and 22°C induced the highest level of beta-carotene production (117.99 mg L-1). The optimal concentrations of KNO3, CO(NH2)2, and NaHCO3 for algae growth were 0.5 g L-1, 0.36 g L-1, and 1.5 g L-1, respectively, while 0, 0.12 g L-1 and 1.5 g L-1 were best suited for beta-carotene accumulation. The highest beta-carotene rate per cell appeared with the highest light intensity (12.21 pg) and lowest temperature (12.47 pg), and the lowest total beta-carotene content appeared at the lowest temperature (15°C). There was not a significant difference in biomass accumulation among the three Dunaliella strains; however, the beta-carotene accumulation of KU XI was higher than that of the other two strains. Conclusions: Light and temperature were both relevant factors that contributed to the growth and beta-carotene accumulation of the three D. salina strains, and NaHCO3 had significantly positive effects on growth. The degree of impact of the different factors on cell growth was temperature > NaHCO3 > light intensity > KNO3 > CO (NH2)2 > strains; the impact on beta-carotene accumulation was temperature > light intensity > KNO3 > CO (NH2)2 > strains > NaHCO3

Genetic diversity and classification of Nelumbo germplasm of different origins by RAPD and ISSR analysis.

With the depletion of fossil fuel resources and the limited availability of petroleum-derived transport fuel, along with the contribution to global warming, the environmental benefits of renewable biofuel are seen as the best alternative source in recent years. Among the third-generation biodiesel feed stocks such as food crops (sugarcane, sugar beet, maize and rapeseed) and non-food crops (Jatropha sp., Cassava sp., lignocellulosic materials), microalgae has been hailed as the third-generation biodiesel. Microalgae are the only fuel source that can be sustainably developed in the near future, and can produce ten times more oil than oleaginous plants. Biodiesel from microalgae has received much attention world-wide in recent years due to its carbon-neutral status. The higher neutral lipid contents of microalgae also surpass terrestrial plants for biofuel production, and microalgae are the largest biomass producers. They can accumulate high concentrations of triacylglycerol as a storage lipid under photooxidative stress and other unfavorable environmental conditions within a short period of time. This chapter provides an overview of the production of biodiesel from microalgae and includes algae cultivation, biomass production, harvesting, and downstream processing, along with a list of companies aiming to develop biodiesel from microalgae.