Phenolic compounds in barley have strong antioxidant, antiradical activity.

Epidemiological studies tell us that consuming whole grains and grain-based products can lead to a reduced risk of a myriad of chronic diseases. The health benefits of grains are based in part on the antioxidant properties of their phytochemicals. Another benefit: cereals are a rich source of dietary fiber which helps in maintaining digestive health, lowering plasma cholesterol and reducing colon cancer.

Canadian scientists wanted to examine the antioxidant potential of barley, an underutilized cereal in North America. Two distinct barley cultivars--Falcon, a hulled cultivar, and Metcalfe, a hull-less cultivar--were pearled into seven fractions separately and extracted with 80% methanol. Researchers analyzed the extracts for their total phenolic content.

Antiradical activity was assessed using photochemiluminescence (PCL). The activity of water-soluble and lipid-soluble antioxidant fractions was reported as Trolox and tocopherol equivalents. In addition, the antioxidant activity of the extracts was determined using the Trolox equivalent antioxidant capacity (TEAC) and 1,1 diphenylpicrylhydrazyl (DPPH) radical scavenging assays.

The total phenolic content of the Falcon and Metcalfe fractions varied from 0.79 to 24 and from 2.85 to 22.48 mg ferulic acid equivalents per g of extract, respectively. Corresponding DPPH radical scavenging capacities ranged from 14% to 93% and from 13% to 61%. For the Falcon fraction, the water-soluble and lipid-soluble antioxidant activities, as measured by PCL, ranged from 30.5 to 327 mmol Trolox equivalents per g of extract and from 36 to 170 mmol tocopherol equivalents per g of extract, respectively. The corresponding values for the Metcalfe fraction were 92 to 143 mmol per g and 34 to 117 mmol per g. The results show that antioxidant phenolic compounds, which are mainly concentrated in the outer three fractions of the barley grain, have strong antioxidant and antiradical activity.

FYI: Hulled barley is the most nutritious of the barleys, since only the tough outer hulls are polished off. Pearled barley is polished more extensively--the outer bran layer is also scrubbed off. It's less nutritious, but more popular since it's not as chewy as hulled barley, and it cooks faster.

Further information. Marta Izydorczyk, Barley Research, Grain Research Laboratory, Canadian Grain Commission, 600-303 Main St., Winnipeg, MB R3C 3G8, Canada; phone: [phone]; fax: [phone]; email: [e-mail].