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and 3% each of deoiled flaxseed meal, mustard meal, and rice bran meal were added
to medium II as supplementation for biomass growth and lipid production.
2.8 Fungal Dry Mass Determination
The biomasses from all the experimental media were harvested by filtering and then
freeze-dried (Eyela FDU-1110, Japan) to constant mass and weighted dry cell weight.
The amount of biomass yield with respect to the substrate consumption, in the term
of, growth yield efficiency, Y X/C , is calculated using Eq. 1.
Y X/C =
X
(C i −C f )
(1)
Biomass yield with respect to carbon substrate consumed, g biomass/g substrate;
where, X, fungal biomass yield at time t, g/L; C i , initial carbon substrate concentration, g/L; and C f , carbon substrate concentration after fermentation, g/L.
2.9 Residual Glucose Analysis
Residual glucose present in the media after fermentation was analyzed using the
DNS method (Miller 1959).
2.10 Extraction of Lipid Compounds from Fungal Dried
Biomass
The dried fungal biomasses were subjected to lipid extraction according to the method
described by Bligh and Dyer (1959) with methanol, water, and chloroform in a ratio
of 2:1:1. The lipid content in biomass, in the term of SCO productivity, Y L/X , was
calculated using Eq. 2.
Y L/ X =
L max
X
(2)
where L max is maximum lipid yield, g/L, and X is biomass yield corresponding to
the maximum lipid yield, g/L.
The lipid yield with respect to carbon substrate consumption, Y L/C , was calculated
using Eq. 3.