The beneficial health effects of Chlorella vulgaris have been associated with the presence of several nutrients and antioxidants, including carotenoids. However, the in vivo bioavailability of Chlorella is still poorly evaluated. In this work, a human intervention study was conducted in 11 healthy men to evaluate the bioavailability of carotenoids within 3 days after the intake of a single dose (6 g) of dried marine Chlorella vulgaris containing lutein (7.08 mg), β-carotene (1.88 mg) and zeaxanthin (1.47 mg). Subjects were instructed to follow a low carotenoid diet during the experimental phase, starting 1 week earlier. On the day of the experiment, dried microalgae formulated in vegetarian hard capsules were ingested, and blood samples were collected up to 72 h for the analysis of plasma carotenoids concentration by high-performance liquid chromatography with diode-array detection. For all carotenoids, the estimated AUC and Cmax values were significantly different from zero (p < 0.05), indicating that a single dose of marine Chlorella vulgaris increased plasma concentrations of lutein (Cmin-corrected AUC = 1002 µg·h/L, Cmax = 20.4 µg/L), β-carotene (AUC = 1302 µg·h/L, Cmax = 34.9 µg/L) and zeaxanthin (AUC = 122.2 µg·h/L, Cmax = 3.4 µg/L). The bioavailability of other compounds, namely, polyunsaturated fatty acids and trace elements, was also assessed post-prandial for the first time, showing that linoleic acid, docosahexaenoic acid and iodine were absorbed after microalgae intake. These findings support the use of Chlorella vulgaris as a source of carotenoids, PUFA and essential trace elements with associated health benefits.
Arbutus unedo L., commonly known as the strawberry-tree fruit, is an endemic species of the Mediterranean flora. Microwave extraction technology has been considered as a fast and “green” method for the production of extracts rich in bioactive compounds, although the energy consumption is high. To overcome this bottleneck, microwave was used as a pretreatment procedure in short time periods. This technique promotes the burst of intracellular vacuoles leading to an increase in the lixiviation of phenolic compounds. Different approaches were tested, namely a solvent-free irradiation (SFI), a solvent-assisted irradiation (SAI) and a pressurized solvent-assisted irradiation (PSAI). After irradiation, a solid–liquid extraction procedure was performed using a mixture of water and ethanol. A kinetic evaluation of the total phenolic content (TPC) was performed using the Folin–Ciocalteu method. For the total anthocyanin content, a UV-spectrophotometric method was used. HPLC-UV and LC-MS were used for TPC and identification of present compounds. Microwave irradiation led to an increase in TPC of extracts after SAI (52%) and PSAI (66%) along with a reduction in time of extraction from 30 min to less than 2 min. The anthocyanin content also increased by 66% for the SAI and PSAI extractions.
16 August 2013 in The Journal of Supercritical Fluids