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Marigold flowers are the main natural source of xanthophylls, and marigold saponified extract is used as an additive in several food and pharmaceutical industries. In this work, the use of a solid-state fermentation (ensilage) process for increasing the yield of xanthophylls extracted from fermented marigold flowers was examined. The process consisted of a mixed culture of three microorganisms (Flavobacterium IIb,Acinetobacter anitratus, andRhizopus nigricans), part of the normal microbiota associated with the marigold flower. These microorganisms had been previously isolated, and were identified as relevant for the ensilage process due to their capacity to produce cellulolytic enzymes. Based on experimental design strategies, optimum operation values were determined for aeration, moisture, agitation, and marigold-to-inoculum ratio in the proposed solid-state fermentation equipment, leading to a xanthophylls yield of 17.8-g/kg dry weight. The optimum achieved represents a 65% increase with respect to the control. HPLC analysis indicated conservation of extracted oleoresin. Based on the experimental results, interactions were identified that could be associated with the heat and mass-transfer reactions taking place within the bioreactor. The insight gained allows conditions that limit growth and metabolic activity to be avoided. [ABSTRACT FROM AUTHOR]

Ornithine decarboxylase from respiratory fungal pathogen, Coccidioides immitis, cloned in the pETCiODC plasmid under control of T7lac promoter, was produced in E. coli BL21(DE3), BL21(DE3)pLysS, BLR(DE3) and EWH319 transformant strains. E. coli BL21(DE3)pLysS-pETCiODC expressed the highest specific activity of ODC, suggesting that this strain could be successfully used for protein structure and drug testing studies. [ABSTRACT FROM AUTHOR]

Abstract: The marigold flower (Tagetes erecta) is one of the richest natural sources of xanthophylls, mainly lutein. Its saponified extract is used as an additive in several food and pharmaceutical industries. However, the efficiency in the xanthophylls extraction from this natural source depends heavily upon an appropriate prior treatment, given to the flower, to increase wall-cells permeability and facilitate the diffusive mechanisms of mass exchange between immiscible phases during the lixiviation process. In this work, the effect of different treatments on marigold flower to increase the xanthophylls extraction efficiency is studied. The results clearly indicate the interrelation that exists between the treatment and the extraction. It is shown that almost full recovery of the xanthophylls contents can be achieved when the marigold is treated with hydrolytic enzymes synthesized by microbiota associated to marigold flowers. These results have significant impact on the cost-efficiency of the process. [Copyright &y& Elsevier]