At today’s consumption level, earth’s oil and gas
reserves has been estimated to deplete in 40 and 64 years,
respectively
. Use of fossil petroleum fuels becoming
unsustainable due to over exploitation and being a great
source of toxic and green house gases that aggravates
global climatic change and becomes the key factor to
global warming issue
. Transesterification is a chemically
catalyzed reaction transforming triglycerides into fatty
acid alkyl ester in the presence of an alcohol (methanol
or ethanol) and a catalyst (alkali or acid) with glycerol
as a byproduct
. Currently, many alternative oil sources
from algae are used for biodiesel production than the
plant crops as their photosynthetic productivity is greatly
higher and are exceedingly rich in oil than other biomass
.
Microalgae are sunlight-driven miniature biochemical
factories that are photosynthetically efficient than
terrestrial plants, easily grown in non-arable land, efficient
CO2
fixers and their oil content exceeds 80% of dry
weight of biomass
. Moreover, average biodiesel
production from microalgae is 10-20 folds higher than
the yield obtained from other plant sources
. Among
microalgae, Cyanophyceae (blue green algae),
Chlorophyceae (green algae), Chrysophyceae (goldenbrown
algae) and Bacillariophyceae (diatoms) are
extensively utilized for biodiesel production.
Cyanobacteria have received considerable attention in
recent years as excellent organisms for renewable biofuel
production because they are the only known prokaryotes
capable of oxygenic photosynthesis, having high-yield oil,
and easily grown in non-arable land.
This study presents biodiesel production from
Oscillatoria annae and optimization of growth medium
to improve the biomass yield in order to obtain higher
biodiesel yield using response surface methodology
(RSM) and central composite rotatable design (CCRD)