Effects of nitrogen on growth and carbohydrate formation in Porphyridium cruentum
Artikel i vetenskaplig tidskrift, 2014

The microalga Porphyridium cruentum (Rhodophyta) has several industrial and pharmaceutical uses, especially for its polysaccharide production. This study aimed to investigate the influence of nitrogen levels as reflected by altered N:P ratios on the production and content of biomass and carbohydrate. N:P molar ratios were altered in batch cultures to range from 1.6 to 50 using the Redfield ratio of 1:16 as reference. Algal growth (estimated as final cell number, biomass concentration and maximum specific growth rate) was negatively affected at low N:P ratios. The optimal N:P ratio for growth was identified at 35-50, with specific growth rates of 0.19 day(-1) and maximum cell concentrations of 59 center dot 10(8) cells L-1 and 1.2 g dry weight of biomass L-1. In addition, variation in cell size was seen. Cells with larger diameters were at higher N:P ratios and smaller cells at lower ratios. The cellular carbohydrate content increased under reduced nitrogen availability. However, because accumulation was moderate at the lowest N:P ratio, 0.4 g per g dry weight biomass compared to 0.24 at the Redfield ratio of 16:1, conditions for increased total carbohydrate formation were identified at the N:P ratios optimal for growth. Additionally, carbohydrates were largely accumulated in late exponential to stationary phase.

RED ALGA PORPHYRIDIUM

CULTURE-MEDIA

NUTRIENT LIMITATION

STARVATION

CHLAMYDOMONAS-REINHARDTI

Nitrogen-to-phosphorous ratio

EXTRACELLULAR POLYSACCHARIDE

PURPUREUM

Red algae

CYCLE

Rhodophyta

AERUGINEUM

Redfield ratio

Författare

Ali Razaghi

Göteborgs universitet

Anna Godhe

Göteborgs universitet

Eva Albers

Chalmers, Kemi- och bioteknik, Industriell Bioteknik

Central European Journal of Biology

1895-104X (ISSN) 1644-3632 (eISSN)

Vol. 9 2 156-162

Drivkrafter

Hållbar utveckling

Ämneskategorier

Cellbiologi

Biokemi och molekylärbiologi

Immunologi

Bioprocessteknik

Mikrobiologi

Genetik

Styrkeområden

Livsvetenskaper och teknik

DOI

10.2478/s11535-013-0248-z