Fucoxanthin, one of the main marine carotenoids, is abundant in macro- and microalgae. Here, fucoxanthin was isolated and structurally identified as the major carotenoid in the diatom Phaeodactylum tricornutum through chromatographic and spectroscopic methods, such as liquid chromatography-positive-ion atmospheric pressure chemical ionization/mass spectroscopy and nuclear magnetic resonance. This pigment was quantified by reverse-phase high-performance liquid chromatography, and a number of extraction procedures were assessed to investigate the effect of solvent type, extraction time, temperature, and extraction method (maceration, ultrasound-assisted extraction, Soxhlet extraction, and pressurized liquid extraction). Among the investigated solvents, ethanol provided the best fucoxanthin extraction yield (15.71 mg/g freeze-dried sample weight). Fucoxanthin content in the extracts produced by the different methods was quite constant (15.42-16.51 mg/g freeze-dried sample weight) but increased steeply based on the percentage of ethanol in water, emphasizing the importance of ethanol in the extraction. The results indicate that P. tricornutum is a rich source of fucoxanthin (at least ten times more abundant than that in macroalgae) that is easily extracted with ethanol, suggesting potential applications in human and animal food, health, and cosmetics.

No abstract

No abstract

Fucoxanthin, a main marine carotenoid, in five species of fucoxanthin-containing microalgae, was quantified by highperformance liquid chromatography. Among the studied species, Isochrysis aff. galbana contained the highest amount of fucoxanthin (18.23 mg/g dried sample). This microalga showed good fucoxanthin extraction efficiency under the tested solvents (methanol, ethanol, acetone, and ethyl acetate), with the exception of n-hexane. In addition, most fucoxanthin (~95%) could be extracted by a single extraction in ethanol within 5 min, and only 15% degradation of fucoxanthin was detected during ethanol extraction for 24 h. The two-phase solvent system of n-hexaneethanol-water with a volume ratio of 10:9:1 was determined to be the best system for the separation of fucoxanthin and lipids from extracts of I. aff. galbana. Under these conditions, fucoxanthin was fractionated in the hydroalcohol phase apart from the hexane phase containing lipids. These results imply that I. aff. galbana can be a commercial source for the spontaneous production of valuable fucoxanthins and lipids.

No abstract

No abstract

Curcuminoids from rhizomes of Curcuma longa possess various biological activities. However, low aqueous solubility and consequent poor bioavailability of curcuminoids are major limitations to their use. In this study, curcuminoids extracted from turmeric powder using stevioside (Ste), rebaudioside A (RebA), or steviol glucosides (SG) were solubilized in water. The optimum extraction condition by Ste, RebA, or SG resulted in 11.3, 9.7, or 6.7mg/ml water soluble curcuminoids. Curcuminoids solubilized in water showed 80% stability at pH from 6.0 to 10.0 after 1week of storage at 25°C. The particle sizes of curcuminoids prepared with Ste, RebA, and SG were 110.8, 95.7, and 32.7nm, respectively. The water soluble turmeric extracts prepared with Ste, RebA, and SG showed the 2,2-diphenyl-1-picrylhydrazyl radical scavenging (SC50) activities of 127.6, 105.4, and 109.8μg/ml, and the inhibition activities (IC50) against NS2B-NS3(pro) from dengue virus type IV of 14.1, 24.0 and 15.3μg/ml, respectively.

No abstract