Producing Docosahexaenoic Acid (DHA)-Rich Algae from Biodiesel-Derived Crude Glycerol: Effects of Impurities on DHA Production and Algal Biomass Composition
- 9 May 2008
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of Agricultural and Food Chemistry
- Vol. 56 (11) , 3933-3939
- https://doi.org/10.1021/jf800602s
Abstract
Crude glycerol is the primary byproduct of the biodiesel industry. Producing docosahexaenoic acid (DHA, 22:6 n-3) through fermentation of the alga Schizochytrium limacinum on crude glycerol provides a unique opportunity to utilize a large quantity of this byproduct. The objective of this work is to investigate the effects of impurities contained in the crude glycerol on DHA production and algal biomass composition. Crude glycerol streams were obtained from different biodiesel refineries. All of the glycerol samples contained methanol, soaps, and various elements including calcium, phosphorus, potassium, silicon, sodium, and zinc. Both methanol and soap were found to negatively influence algal DHA production; these two impurities can be removed from culture medium by evaporation through autoclaving (for methanol) and by precipitation through pH adjustment (for soap). The glycerol-derived algal biomass contained 45−50% lipid, 14−20% protein, and 25% carbohydrate, with 8−13% ash content. Palmitic acid (C16:0) and DHA were the two major fatty acids in the algal lipid. The algal biomass was rich in lysine and cysteine, relative to many common feedstuffs. Elemental analysis by inductively coupled plasma showed that boron, calcium, copper, iron, magnesium, phosphorus, potassium, silicon, sodium, and sulfur were present in the biomass, whereas no heavy metals (such as mercury) were detected in the algal biomass. Overall, the results show that crude glycerol was a suitable carbon source for algal fermentation. The crude glycerol-derived algal biomass had a high level of DHA and a nutritional profile similar to that of commercial algal biomass, suggesting a great potential for using crude glycerol-derived algae in omega-3-fortified food or feed.Keywords
This publication has 29 references indexed in Scilit:
- A laboratory study of producing docosahexaenoic acid from biodiesel-waste glycerol by microalgal fermentationPublished by Elsevier ,2007
- Anaerobic fermentation of glycerol: a path to economic viability for the biofuels industryCurrent Opinion in Biotechnology, 2007
- Dehydration of glycerol to acetol via catalytic reactive distillationAIChE Journal, 2006
- Microbial production of 1,3-propanediol by Klebsiella pneumoniae using crude glycerol from biodiesel preparationsBiotechnology Letters, 2006
- Anaerobic fermentation of glycerol byEscherichia coli: A new platform for metabolic engineeringBiotechnology & Bioengineering, 2006
- Schizochytrium limacinum SR-21 as a source of docosahexaenoic acid: optimal growth and use as a dietary supplement for laying hensAustralian Journal of Agricultural Research, 2006
- Removal of Residual Catalyst from Simulated Biodiesel's Crude Glycerol for Glycerol Hydrogenolysis to Propylene GlycolIndustrial & Engineering Chemistry Research, 2005
- Utilization of glycerol as carbon source on the growth, pigment and lipid production inSpirulina platensisInternational Journal of Food Sciences and Nutrition, 2005
- Advanced DHA, EPA and ArA enrichment materials for marine aquaculture using single cell heterotrophsAquaculture, 2002
- INHIBITION OF UNICELLULAR ALGAE BY SYNTHETIC SURFACE‐ACTIVE AGENTSJournal of Phycology, 1965