A close monitoring of Variations in Fatty acid profile of Isochrysis galbana under conditions of limited Nutrition
A close monitoring of Variations in Fatty acid profile of Isochrysis galbana under conditions of limited Nutrition
Date
2020
Authors
Ganga, Rajani S.
Anandan, R.
Joseph, Aneykutty
Journal Title
Journal ISSN
Volume Title
Publisher
Society of Fisheries Technologists (India)
Abstract
The current study was aimed at investigating the
possible deviations in the degree of unsaturation of
fatty acid components in the marine microalga
Isochrysis galbana, under conditions of low nitrogen
as well as low phosphorus concentrations. Standard
f/2 medium in filtered and sterilized sea water of
salinity 33ppt was used as control/N100. The other
treatments used were f/2 medium with 25% nitrogen
source (N25) and f/2 medium with 25% phosphorus
source (P25). For control cultures, saturated fatty
acids (SFAs) accounted for over 70.66% of the total
fatty acids, whereas it was only 62.96% in nitrogen
limited cultures and 60.17% in phosphorus limited
ones. The present study reveals that nutrient stress
provided a remarkable elevation in the degree of
unsaturation. The value of monounsaturated fatty
acids (MUFAs) was maximum for N25 cultures
(22.20%) followed by P25 (19.62%) whereas it was
16.81% for control. Among the three treatments, the
highest value of polyunsaturated fatty acids (PUFAs)
observed in the P25 cultures (20.21%) followed by
14.84% (N25) while it was only 12.52% for control
cultures. One way analysis of data brought to light
that nutrient stress can influence fatty acid pattern
of the microalga significantly (p<0.05). The present
observations suggest that low availability of macronutrients
such as nitrogen or phosphorus can shift
the fatty acid profile from saturated to unsaturated.
Description
Keywords
Isochrysis galbana, nutrient limitation, saturated fatty acids, monounsaturated fatty acids