Fruits of the Future?
Posted on: 03/12/2007
by Kyle Bradley

Below is an excerpt from Fruits of the future.

Apples, oranges and bananas are super fruits, but not superfruits. These conventional fruits have laudable nutrient profiles and will always be great, healthy options, but they may soon be competing on a large scale with more exotic fruits. “The term superfruits has gone from being a catch-all phrase used by manufacturers to refer to new, exotic fruits with high antioxidant properties to being an accepted category of products on the retail and consumer level,” said Alex Moffett, president of Renaissance Herbs.

Discussion of superfruits in the health arena has centered on their antioxidant capacities, numerically referenced as ORAC values, and the potential role they may play in chipping away at diseases great and small. Research on these compounds’ effects on the oxidization of cholesterol continues to mount, and manufacturers are meeting increasing market demand for these antioxidant-rich ingredients. Exotic sources such as pomegranate, mangosteen, goji, acai­, noni, camu camu and others are gaining acceptance because of promising research.

Superfruit Tutorial

Pomegranates’ (Punica granatum L.) antioxidant potential has been explored for more than a decade and, according to Paul M. Gross, Ph.D., pomegranate has been the subject of 35 medical research studies since 1990, including 27 reports within the past six years. The antioxidant compounds in pomegranate pericarp are known as punicalagins. Gross explained: “Chemically, punicalagins are considered tannins, which hydrolyze during metabolism to yield ellagic acid, a flavanol of the phenolic superfamily.” A 2006 study documented the anti-oxidative effects of pomegranate consumption on apolipoprotein e levels and cellular uptake of oxidized lipids in relation to atherosclerosis development in mice.1 Consumption of whole fruit pomegranate byproduct resulted in a significant reduction in atherosclerotic lesion size by up to 57 percent. Also, low-density lipoprotein (LDL) cholesterol uptake was reduced by up to 19 percent. More recently, pomegranate antioxidants are being studied for their ability to help the body fight cancer. By tally of the National Institutes of Health (NIH), three studies on the efficacy of pomegranate consumption are in the recruiting stages; two will explore prostate cancer, and the third enlarging of the prostate.

Another exotic fruit generating interest is mangosteen (Garcinia mangostana). As with other superfruits, varying parts of the fruit provide health benefits. According to Gross, “The purple pericarp [of the mangosteen], which is not considered edible, is a rich source for extracting antioxidant phytochemicals, whereas the interior flesh is valued as a juice or pulp product.”

Two primary xanthone extracts “garcinol and mangostina” have “potential as anti-inflammatory agents with preliminary evidence for inhibiting cyclo-oxygenase (COX) enzymes and carcinogenic effects,” he said. A 2004 study explored the antiproliferative, apoptotic and antioxidative properties of crude methanolic extract (CME) from the pericarp of the mangosteen on human breast cancer cells.2 Researchers “found that antiproliferative effect of CME was associated with apoptosis on breast cancer cell line by determinations of morphological changes and oligonucleosomal DNA fragments”, and that the extract “has potential for cancer chemoprevention.”

Wayne Geilman, Ph.D., senior research scientist at Pure Fruit Technologies, added to the list of mangosteen’s abilities: “We found the xanthones in mangosteen are COX-2 inhibitors,” he said. If you stop that enzyme, you don’t get inflammation, and if you don’t get inflammation, you don’t get pain.” Other uses of mangosteen components include appetite suppression, and use in topical skin care products.

Wolfberry (Lycium barbarum), also referred to as “Goji“, has also come to the forefront of exotic health foods for an extensive nutrient profile. Clinical trials involving wolfberry are spotty, but animal trials suggest potential benefits for humans. A 2006 study found the antioxidant polysaccharides in wolfberries reduce the risks of lipid peroxidation accelerated by free radicals in aged mice.3 Another 2006 study noted the fruit’s nutritional value in Chinese culture for addressing liver, kidney and vision problems, and found extracts of the fruit to have cytoprotective effects against reducing stress on the endoplasmic reticulum.4 Because the berries are originally from China and have been part of Chinese diets for thousands of years, indigenous literature regarding myriad health benefits of the berries has given formulators the initiative to bank on the berries’ nutrient profile, said Gross.

Noni fruit, from Southeast Asia, also has limited clinical research to date. However, the fruit’s use in Polynesian medicines for hundreds of years has been the catalyst for research. Despite being approved as a Novel Food by the European Commission in 2003, liver toxicology issues have been a marketing hurdle for manufacturers. A recent study found – no link between adverse effects on liver and consumption of Noni juice,” but cautioned that, “clinical data are essentially lacking.”5 The other significant issue with noni fruit (Morinda citrifolia) is its foul taste. Tannins in ripened specimens impart a strong taste and odor to the fruit, so companies have developed processes for removing the tannins to enhance product taste.

Acai berries (Euterpe oleracea Mart) aren’t known for foul taste but, as with wolfberry, clinical research is limited. Two recent studies have, however, assayed the antioxidant capacities of both acai­ fruit and seeds. Both measured total oxidant scavenging capacity (TOSC), the first reporting: “The antioxidant capacities of all purple acai­ samples were found to be excellent against peroxyl radicals, good against peroxynitrite and poor against hydroxyl radicals compared with common European fruit and vegetable juices”;6 the second noting:

“The extracts exhibit good antioxidant capacity against peroxyl radicals, similar to the capacity of the pulp.”7 The study showed the antioxidant capacity against peroxynitrite and hydroxyl radicals to be even higher, but concluded much of the antioxidant capacity of the seeds came from yet unidentified compounds. Camu camu (Myrciaria dubia) has been spotlighted for its high vitamin C and anthocyanin levels. Like several other superfruits, trials involving camu camu are scarce. Research on the bright orange berries has increased as companies have addressed consumer demand for all natural vitamin C sources and attempted to capitalize on innovative antioxidant source demand.

As with most of the fruits under the superfruits canopy, camu camu has much potential for scavenging free radicals, ultimately combating oxidation of cholesterol.

References

1. West BJ et al. “Noni juice is not hepatotoxic.” World J Gastroenterol. 2006 Jun 14;12(22):3616-9. http://www.pubmed.gov/. Rosenblatt M et al. “Pomegranate byproduct administration to apolipoprotein e-deficient mice attenuates atherosclerosis development as a result of decreased macrophage oxidative stress and reduced cellular uptake of oxidized low-density lipoprotein.” J Agric Food Chem. 2006 Mar 8;54(5):1928-35. http://www.pubmed.gov/ . Rosenblatt M et al. “Pomegranate byproduct administration to apolipoprotein e-deficient mice attenuates atherosclerosis development as a result of decreased macrophage oxidative stress and reduced cellular uptake of oxidized low-density lipoprotein.” 2006 Mar 8;54(5):1928-35.

2. Rosenblatt M et al. “Pomegranate byproduct administration to apolipoprotein e-deficient mice attenuates atherosclerosis development as a result of decreased macrophage oxidative stress and reduced cellular uptake of oxidized low-density lipoprotein.” 2006 Mar 8;54(5):1928-35.2. Moongkarndi P et al. “Antiproliferation, antioxidation and induction of apoptosis by Garcinia mangostana (mangosteen) on SKBR3 human breast cancer cell line.” J Ethnopharmacol. 2004 Jan;90(1):161-6. http://www.pubmed.gov/

3. Li XM et al. “Effect of the Lycium barbarum polysaccharides on age-related oxidative stress in aged mice.” J Ethnopharmacol. 2006 Dec 28. http://www.pubmed.gov/

4. Yu MS et al. “Cytoprotective effects of Lycium barbarum against reducing stress on endoplasmic reticulum.” Int J Mol Med. 2006 Jun;17(6):1157-61. http://www.pubmed.gov/

5. Potterat O and Hamburger M. “Morinda citrifolia (Noni) Fruit – Phytochemistry, Pharmacology, Safety.” Planta Med. 2007 Feb 7. http://www.pubmed.gov/

6. Lichtenthaler R et al. “Total oxidant scavenging capacities of Euterpe oleracea Mart. (Acai) fruits.” Int J Food Sci Nutr. 2005 Feb;56(1):53-64. http://www.pubmed.gov/

7. Rodrigues RB et al. “Total oxidant scavenging capacity of Euterpe oleracea Mart. (Acai­) seeds and identification of their polyphenolic compounds.” J Agric Food Chem. 2006 Jun 14;54(12):4162-7. http://www.pubmed.gov/