Location: National Peanut Research LaboratoryTitle: Optimization of medium components using orthogonal arrays for Linolenic acid production by Spirulina platensis Author
Submitted to: Korean Chemical Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/14/2014
Publication Date: 5/15/2014
Citation: Ronda, R.R., Parapudi, P.L., Vamula, S., Tumma, S., Botlagunta, M., Settaluri, V.S., Lele, S., Sharma, S., Kandala, C. 2014. Optimization of medium components using orthogonal arrays for Linolenic acid production by Spirulina platensis. Korean Chemical Society. 31(10):1839-1844. doi: 10.1007/s11814-014-0082-7. Interpretive Summary: GLA ('-Linolenic acid), an important omega-6 fatty acid, is an antecedent in the production of prostaglandin E1 and other essential fatty acids. It has a wide variety of applications in pharmaceuticals, feed, and functional foods. In addition, GLA plays an active role in the treatment of various disorders, such as malignant glioma, rheumatoid arthritis, hypertension , diabetic neuropathy, and atopic eczema. The blue-green alga Spirulina platensis is a well-known algal source of '-Linolenic acid. The average lipid content observed in this alga was 4-7%, and GLA accounts for a maximum of 31% of the total fatty acids. To date, there are only a few studies on the alga regarding the effect of medium components on GLA production . Hence, the present work reports the optimization of GLA production by Spirulina platensis with respect to carbon, nitrogen, mineral salts and pH in the medium. The best sources were considered factors that affect GLA production. By using an orthogonal array, the effect of each factor was further evaluated in combination with other factors. The orthogonal experiments demonstrated increased GLA production. In this study, the improvised concentration levels of medium components showed a 1.4-fold increase in GLA production (13.5mgL-1 at 0.25% NaNO3 against 19.2mgL-1 at 0.3% NaNO3), compared with the original inorganic SOT medium. Because medium components are one of several other factors that influence algal growth and fatty acid production, our results indicate a greater scope for further increases in GLA yield by cultivating alga in this medium in optimal environmental conditions.
Technical Abstract: This work describes the medium optimization of '-Linolenic acid (GLA) production by Spirulina platensis using one-factor and orthogonal array design methods. In the one-factor experiments, NaHCO3 (9 mg L-1), NaNO3 (13.5 mg L-1) and MgSO4•7H2O (11.85 mg L-1) proved to be the best components for GLA production. The optimal pH for GLA production by the alga was 9.2. Based on the delta values, NaHCO3 showed the greatest effect on the GLA production of the various factors tested, followed in decreasing order by MgSO4•7H2O, NaNO3 and K2SO4. The maximum GLA yield obtained was 19.2 mgL-1 in the presence of optimum concentrations of NaHCO3 (20 g L-1), NaNO3(3 g L-1), MgSO4•7H2O (0.5 g L-1) and K2SO4 (1.5 g L-1). Because of the slow growth rate of the algae, the practice of robust orthogonal array methods during the optimization of medium components can result in the production of an optimal biomass and a higher GLA yield for nutraceutical applications.