The study, published in BioFactors, suggests that supplementing the ingestion of probiotics with certain nutrients may increase the beneficial effects that the microbacteria.
According to researchers, led by Dr Supriya Yadav from the Agharkar Research Institute, India, the ingestion of probiotics in conjunction with micronutrient supplementation may offer a double beneficial effect to the host by improving zinc and iron status, and by boosting the microbial balance of the colon.
“The present study shows enhancing effect of quercetin and gallic acid toward growth of probiotics and also the inhibitory effect of quercetin to growth of E. coli. This inhibitory activity of quercetin toward E. coli has not been proved yet by others,” said the researchers.
Dr. Yadav and colleagues said that the results of the study may encourage formulation development that could lead to symbiotic supplements made up of probiotics and certain micronutrients that have been shown to be beneficial on the effects of them.
The researchers noted that there is a recent trend in the development of functional foods and nutraceuticals is to develop synbiotic formulations.
They said that the action of probiotic micro-organisms in the formulation of foods has been shown to improve the quantity, availability, and digestibility of some dietary nutrient, and has also been reported to increase the bioavailability of micronutrients like zinc and iron.
However, according to Yadav and colleagues, the reverse effect, that is the action of micronutrients, antioxidants, and other phytoingredients on growth of probiotics has not been investigated.
The new study, therefore investigated the influence of selected micronutrients and phytochemical and dietary factors (including zinc, iron, quercetin, and gallic acid, phytic acid and oxalic acid), on the growth of probiotics.
The effect of eight nutritional and anti-nutritional factors (zinc sulphate, zinc carbonate, ferrous sulphate, ferric citrate, quercetin, gallic acid, phytic acid, and oxalic acid) on the growth of two standard probiotic cultures (Lactobacillus acidophilus, and L. plantarum), two bifidobacterium isolates, one marketed consortium (containing six lactobacilli and two bifidobacterial cultures), and E. coli, was monitored individually to generate a dose response curve.
The authors reported that quercetin and zinc sulphate showed significant positive effect for Lactobacillus acidophilus and the consortium probiotic, but reported only slight, or no effect on growth for the other probiotics.
Oxalic acid also had positive effect for L. acidophilus and the consortium probiotic, with no effect on growth of other probiotics.
Further, Yadav and co workers observed zinc sulphate, ferrous sulphate, quercetin, and oxalic acid to significantly inhibit the growth of E. coli.
“Our results not only support the usefulness of some probiotics in degradation of oxalic acid but also indicate inhibitory potential of oxalic acid in controlling the growth of commensal E coli,” said the researchers.
They said that such changes could have a salutary effect on kidney stone formation rates as well as on the control of pathogens.
“Supplementation of probiotics and prebiotics with zinc sulphate, iron sulphate, quercetin, and gallic acid might be beneficial to the host as well as to intestinal probiotics,” concluded the researchers.
“Factors such as zinc sulphate, iron sulphate, and oxalic acid showed strong inhibitory effect on growth of the commensal E coli. Thus, their presence might assist the probiotic microbiota to resist against pathogens,” they added.
Commenting independently on the study, Professor Glenn Gibson from the University of Reading told NutraIngredients agreed with the notion that synbiotic formulations which included micronutrients in addition to pre- and pro- biotics may be beneficial.
“Vitamins are popular supplements and consumer awareness is high. Probiotics probably have even more health benefits, but the awareness is reduced … It makes sense to combine them such that consumers have the multiple health aspects but in products that they are used too,” said Gibson.
However Professor Tine Rask Licht, from the National Food Institute at the Technical University of Denmark told NutraIngredients that the results of the current study are a long way from showing such beneficial effects.
“It is difficult to extrapolate from lab studies to studies in humans or animals … many more studies will be needed in order to elucidate whether there is any clinically relevant effect,” said Prof. Licht.
Published online ahead of print, doi: 10.1002/biof.137