Maize whole grains show prebiotic potential
The study published in the British Journal of Nutrition suggests that consuming 48 grams per day of cereal enriched nearly 30 percent whole grain from maize semolina significantly increases the in vivo levels of bifidobacteria.
“To date, this is the first time that breakfast cereal enriched with maize as a whole grain source has been reported from in vivo data to be potentially prebiotic,” wrote the researchers, led by Dr Andrew L. Carvalho-Wells from Reading University – one of the world’s leading institutions for prebiotic research.
The research study was funded by Cereal Partners, a collaboration between Nestle and General Mills.
Beneficial for bacteria
Prebiotics are defined as “non-digestible (by the host) food ingredients that have a beneficial effect through their selective metabolism in the intestinal tract” (Gibson et al. 2004).
Supplementation of the gut with prebiotic fermentable carbohydrates such as inulin and resistant starch has been suggested to decrease the risk of chronic disease, and can be in part credited with modulating gut microbiota.
Commercially established prebiotics are often oligosaccharides such as inulin and oligofructose, however, recent research into potential prebiotics has suggested sources ranging from barley extract to almonds.
The authors noted that whole grains contain a “complex mix of bioactive components”, that have been suggested to show prebiotic potential – however they added that more research is needed “to determine the impact of novel whole grain sources on the gut microbiota.”
The new study aimed to determine the prebiotic potential of a breakfast cereal enriched with maize derived whole grain.
Recent research has suggested that consumption of a minimally processed source of whole grain has a probable prebiotic effect compared with wheat bran.
Significant effect
Consumption of maize whole grain cereal for 21 days was reported to have a significant effect on the observed levels of bifidobacteria.
However, the researchers also saw a non-significant increase in bifdobacteria after consumption of the non whole grain enriched control cereal.
A comparison between both enriched and non-enriched groups showed no significant difference before supplementation, however, post- supplementation the groups were reported to show “borderline significance.”
Consumption of maize derived whole grain “resulted in a significant mean increase in faecal bifidobacteria, which is considered a positive indicator of prebiotic activity,” wrote the authors.
The study observed the best bifidogenic effects in people with initially low populations of bifidobacteria, whilst individuals with initially high levels showed a much lower response.
Additional evidence
The authors concluded that consumption of whole grain maize cereal results in a beneficial shift in the faecal microbiota, which suggested a potential prebiotic effect for maize whole grain – and “could provide additional evidence for the health benefits of whole grains.”
“We do not as yet know all the components of these foods responsible for these observed prebiotic effects,” added they added.
Source: British Journal of Nutrition
Published online ahead of print, doi: 10.1017/S0007114510002084
“Determination of the in vivo prebiotic potential of a maize-based whole grain breakfast cereal: a human feeding study”
Authors: A.L. Carvalho-Wells, K. Helmolz, C. Nodet, C. Molzer, C. Leonard, B. McKevith, F. Thielecke, K.G. Jackson, K,M. Tuohy
