Re: Consumption of Xanthone-rich Beverage Enhances Plasma Antioxidant Capacity in Healthy Adults

PDF (Download)	Mangosteen (Garcinia mangostana, Clusiaceae) Xanthones Antioxidant Capacity
Date: 03-31-2015	HC# 031531-517

Re: Consumption of Xanthone-rich Beverage Enhances Plasma Antioxidant Capacity in Healthy Adults

Xie Z, Sintara M, Chang T, Ou B. Functional beverage of Garcinia mangostana (mangosteen) enhances plasma antioxidant capacity in healthy adults. Food Sci Nutr. 2015;3(1):32-38.

Mangosteen (Garcinia mangostana, Clusiaceae) is associated with various health-promoting effects, including anti-inflammatory, antibacterial, cardioprotective, and antioxidant activities. Xanthones are the compounds in mangosteen thought to be responsible for its bioactivity; its most abundant xanthone is α-mangostin. These authors conducted a randomized, double-blind, placebo-controlled clinical trial to determine the bioavailability and antioxidant capacity of α-mangostin and vitamins B₂ and B₅ found in the mangosteen-based functional beverage Verve^® (Vemma Nutrition Co.; Tempe, Arizona).

Twenty healthy subjects (10 men and 10 women), aged 18-60 years, were enrolled in this 6-hour study. They were randomly assigned, with the same number of men and women in each group, to either the Verve or the placebo group.

After baseline tests were conducted, the subjects received either a single daily dose (245 mL) of Verve energy drink or placebo. Verve is a multivitamin/antioxidant liquid nutritional beverage containing vitamins, green tea (Camellia sinensis, Theaceae) leaf, aloe vera (Aloe vera, Xanthorrhoeaceae) gel, mangosteen fruit juice, mangosteen extract (pericarp), and caffeine. The placebo (Vemma Nutrition Co.) was a fructose liquid that looked and tasted like Verve but with no active ingredients.

Blood samples were drawn from each subject at baseline and at 1, 2, 4, and 6 hours after drinking the beverage. The authors report increased plasma concentrations of α-mangostin in the Verve group; no detectable α-mangostin was found in the placebo group. The α-mangostin plasma concentration reached its maximum, 4.16 ± 2.85 mg/mL, 1 hour after Verve consumption and remained elevated throughout the 6-hour trial.

Verve is also enriched with vitamins B₂ and B₅. In the Verve group, both vitamins B₂ and B₅ were found to be bioavailable. One hour after consumption, plasma concentrations of both vitamins reached the highest level; 5.61 ± 2.59 ng/mL for B₂ and 64.41 ± 26.89 ng/mL for B₅. The authors noted the increase in the vitamin concentrations coincided with α-mangostin absorption.

At 1-hour postconsumption in the Verve group, the plasma antioxidant capacity, as measured by oxygen radical absorbance capacity (ORAC), increased 60%. The ORAC values declined gradually, becoming stable between 4 and 6 hours, when the values were 10% higher than baseline values. In the placebo group, the antioxidant activity in plasma decreased slightly during the 6 hours.

"The increases in plasma B vitamins and α-mangostin following Verve consumption indicate that at least a small part of the increase in ORAC may be accounted for by absorbed B vitamins and α-mangostin," write the authors, also noting that the vitamin E, vitamin C, green tea, and aloe vera in Verve are known to have antioxidant activity.

Verve combines antioxidants that are water-soluble (vitamin C, catechins, and polysaccharides) and fat-soluble (vitamin E and α-mangostin). The authors attribute the synergy between those water-soluble and fat-soluble antioxidants as another possible explanation for its antioxidant health benefit.

Other mechanisms suggested to be responsible for the increased ORAC values seen in the Verve group are the scavenging of free radicals by the beverage's bioavailable antioxidants and upregulating of the Nrf2 signaling pathway by the phytochemicals, resulting in increased endogenous antioxidant activity.

Concluding that they determined the physiological availability of α-mangostin and B vitamins present in the Verve beverage and their effects on the degree of antioxidant potency, the authors write, "Our results suggest that Verve is an excellent source to obtain balanced natural antioxidants to maintain well-being and possibly against chronic diseases caused by the aging process." However, investigation into the specific mechanisms of synergy among the various antioxidants, and further translational effects in more and larger clinical studies, is certainly warranted.

―Shari Henson