Betalains
Absorption, excretion, and distribution of dietary antioxidant betalains in LDLs: potential health effects of betalains in humans. (1/2)
BACKGROUND: Betalains were recently identified as natural antioxidants. However, little is known about their bioavailability from dietary sources. OBJECTIVE: The objective was to evaluate the bioavailability of betalains from dietary sources. DESIGN: The plasma kinetics and urinary excretion of betalains were studied in healthy volunteers (n = 8) after a single ingestion of 500 g cactus pear fruit pulp, which provided 28 and 16 mg indicaxanthin and betanin, respectively. The incorporation of betalains in LDL and the resistance of the particles to ex vivo-induced oxidation was also researched. RESULTS: Betanin and indicaxanthin reached their maximum plasma concentrations 3 h after the fruit meal and declined according to first-order kinetics. The half-life of betanin (0.94 +/- 0.07 h) was shorter than that of indicaxanthin (2.36 +/- 0.17 h). Both compounds had disappeared from plasma by 12 h after intake. The urinary excretion of indicaxanthin and betanin over 12 h represented 76 +/- 3.0% and 3.7 +/- 0.2%, respectively, of the ingested compounds. LDL isolated 3 and 5 h after the fruit meal incorporated betalains at concentrations of 100.5 +/- 11 and 50 +/- 7.2 pmol/mg LDL protein, respectively. In addition, the particles appeared more resistant to ex vivo-induced oxidative injury than did the samples isolated before fruit ingestion (P < 0.05)-the higher the amount of betalains incorporated, the higher the resistance. The concentrations of vitamin E and beta-carotene in LDL did not change significantly after fruit ingestion. CONCLUSION: Our results show that cactus pear fruit is a source of bioavailable betalains and suggest that indicaxanthin and betanin may be involved in the observed protection of LDL against ex vivo-induced oxidative modifications. (+info)Betalain production is possible in anthocyanin-producing plant species given the presence of DOPA-dioxygenase and L-DOPA. (2/2)
(+info)Betalains are a group of pigments that are responsible for the red, yellow, and purple colors in some fruits, vegetables, and flowers. They are water-soluble nitrogenous vacuolar pigments that are synthesized from tyrosine. Betalains are divided into two categories: betacyanins (red-violet) and betaxanthins (yellow-orange).
Betalains have antioxidant properties, which contribute to their potential health benefits. They are found in a limited number of plant families, including the Caryophyllales order, which includes beets, chard, amaranth, and prickly pear cactus. Unlike anthocyanins, which are another group of pigments commonly found in plants, betalains do not appear to be present in significant amounts in green leafy vegetables or other commonly consumed fruits and vegetables.
Betaxanthins are a type of betalain pigments that are typically found in plants of the order Caryophyllales, which includes beets, chard, and amaranth. These pigments have antioxidant properties and are believed to contribute to the health benefits of these vegetables. Betaxanthins are yellow or orange in color and can be used as natural food colorings. They are water-soluble and tend to be less stable than other types of pigments, such as carotenoids. In addition to their antioxidant properties, betaxanthins have also been shown to have anti-inflammatory and neuroprotective effects.